Introduce nvim namespace: Move files.

Move files from src/ to src/nvim/.
- src/nvim/ becomes the new root dir for nvim executable sources.
- src/libnvim/ is planned to become root dir of the neovim library.

1 files changed, 0 insertions, 4378 deletions

diff --git a/src/memline.c b/src/memline.c
deleted file mode 100644
index a01506756f..0000000000
--- a/src/memline.c
+++ /dev/null
@@ -1,4378 +0,0 @@
-/*
- * VIM - Vi IMproved	by Bram Moolenaar
- *
- * Do ":help uganda"  in Vim to read copying and usage conditions.
- * Do ":help credits" in Vim to see a list of people who contributed.
- * See README.txt for an overview of the Vim source code.
- */
-
-/* for debugging */
-/* #define CHECK(c, s)	if (c) EMSG(s) */
-#define CHECK(c, s)
-
-/*
- * memline.c: Contains the functions for appending, deleting and changing the
- * text lines. The memfile functions are used to store the information in
- * blocks of memory, backed up by a file. The structure of the information is
- * a tree.  The root of the tree is a pointer block. The leaves of the tree
- * are data blocks. In between may be several layers of pointer blocks,
- * forming branches.
- *
- * Three types of blocks are used:
- * - Block nr 0 contains information for recovery
- * - Pointer blocks contain list of pointers to other blocks.
- * - Data blocks contain the actual text.
- *
- * Block nr 0 contains the block0 structure (see below).
- *
- * Block nr 1 is the first pointer block. It is the root of the tree.
- * Other pointer blocks are branches.
- *
- *  If a line is too big to fit in a single page, the block containing that
- *  line is made big enough to hold the line. It may span several pages.
- *  Otherwise all blocks are one page.
- *
- *  A data block that was filled when starting to edit a file and was not
- *  changed since then, can have a negative block number. This means that it
- *  has not yet been assigned a place in the file. When recovering, the lines
- *  in this data block can be read from the original file. When the block is
- *  changed (lines appended/deleted/changed) or when it is flushed it gets a
- *  positive number. Use mf_trans_del() to get the new number, before calling
- *  mf_get().
- */
-
-#include <string.h>
-
-#include "vim.h"
-#include "memline.h"
-#include "blowfish.h"
-#include "buffer.h"
-#include "eval.h"
-#include "fileio.h"
-#include "main.h"
-#include "mark.h"
-#include "mbyte.h"
-#include "memfile.h"
-#include "memory.h"
-#include "message.h"
-#include "misc1.h"
-#include "misc2.h"
-#include "crypt.h"
-#include "option.h"
-#include "os_unix.h"
-#include "path.h"
-#include "screen.h"
-#include "sha256.h"
-#include "spell.h"
-#include "term.h"
-#include "ui.h"
-#include "undo.h"
-#include "window.h"
-#include "os/os.h"
-
-#ifndef UNIX            /* it's in os_unix_defs.h for Unix */
-# include <time.h>
-#endif
-
-typedef struct block0 ZERO_BL;              /* contents of the first block */
-typedef struct pointer_block PTR_BL;        /* contents of a pointer block */
-typedef struct data_block DATA_BL;          /* contents of a data block */
-typedef struct pointer_entry PTR_EN;        /* block/line-count pair */
-
-#define DATA_ID        (('d' << 8) + 'a')   /* data block id */
-#define PTR_ID         (('p' << 8) + 't')   /* pointer block id */
-#define BLOCK0_ID0     'b'                  /* block 0 id 0 */
-#define BLOCK0_ID1     '0'                  /* block 0 id 1 */
-#define BLOCK0_ID1_C0  'c'                  /* block 0 id 1 'cm' 0 */
-#define BLOCK0_ID1_C1  'C'                  /* block 0 id 1 'cm' 1 */
-
-/*
- * pointer to a block, used in a pointer block
- */
-struct pointer_entry {
-  blocknr_T pe_bnum;            /* block number */
-  linenr_T pe_line_count;       /* number of lines in this branch */
-  linenr_T pe_old_lnum;         /* lnum for this block (for recovery) */
-  int pe_page_count;            /* number of pages in block pe_bnum */
-};
-
-/*
- * A pointer block contains a list of branches in the tree.
- */
-struct pointer_block {
-  uint16_t pb_id;               /* ID for pointer block: PTR_ID */
-  uint16_t pb_count;            /* number of pointers in this block */
-  uint16_t pb_count_max;        /* maximum value for pb_count */
-  PTR_EN pb_pointer[1];         /* list of pointers to blocks (actually longer)
-                                 * followed by empty space until end of page */
-};
-
-/*
- * A data block is a leaf in the tree.
- *
- * The text of the lines is at the end of the block. The text of the first line
- * in the block is put at the end, the text of the second line in front of it,
- * etc. Thus the order of the lines is the opposite of the line number.
- */
-struct data_block {
-  uint16_t db_id;               /* ID for data block: DATA_ID */
-  unsigned db_free;             /* free space available */
-  unsigned db_txt_start;        /* byte where text starts */
-  unsigned db_txt_end;          /* byte just after data block */
-  linenr_T db_line_count;       /* number of lines in this block */
-  unsigned db_index[1];         /* index for start of line (actually bigger)
-                                 * followed by empty space upto db_txt_start
-                                 * followed by the text in the lines until
-                                 * end of page */
-};
-
-/*
- * The low bits of db_index hold the actual index. The topmost bit is
- * used for the global command to be able to mark a line.
- * This method is not clean, but otherwise there would be at least one extra
- * byte used for each line.
- * The mark has to be in this place to keep it with the correct line when other
- * lines are inserted or deleted.
- */
-#define DB_MARKED       ((unsigned)1 << ((sizeof(unsigned) * 8) - 1))
-#define DB_INDEX_MASK   (~DB_MARKED)
-
-#define INDEX_SIZE  (sizeof(unsigned))      /* size of one db_index entry */
-#define HEADER_SIZE (sizeof(DATA_BL) - INDEX_SIZE)  /* size of data block header */
-
-#define B0_FNAME_SIZE_ORG       900     /* what it was in older versions */
-#define B0_FNAME_SIZE_NOCRYPT   898     /* 2 bytes used for other things */
-#define B0_FNAME_SIZE_CRYPT     890     /* 10 bytes used for other things */
-#define B0_UNAME_SIZE           40
-#define B0_HNAME_SIZE           40
-/*
- * Restrict the numbers to 32 bits, otherwise most compilers will complain.
- * This won't detect a 64 bit machine that only swaps a byte in the top 32
- * bits, but that is crazy anyway.
- */
-#define B0_MAGIC_LONG   0x30313233L
-#define B0_MAGIC_INT    0x20212223L
-#define B0_MAGIC_SHORT  0x10111213L
-#define B0_MAGIC_CHAR   0x55
-
-/*
- * Block zero holds all info about the swap file.
- *
- * NOTE: DEFINITION OF BLOCK 0 SHOULD NOT CHANGE! It would make all existing
- * swap files unusable!
- *
- * If size of block0 changes anyway, adjust MIN_SWAP_PAGE_SIZE in vim.h!!
- *
- * This block is built up of single bytes, to make it portable across
- * different machines. b0_magic_* is used to check the byte order and size of
- * variables, because the rest of the swap file is not portable.
- */
-struct block0 {
-  char_u b0_id[2];              /* id for block 0: BLOCK0_ID0 and BLOCK0_ID1,
-                                 * BLOCK0_ID1_C0, BLOCK0_ID1_C1 */
-  char_u b0_version[10];        /* Vim version string */
-  char_u b0_page_size[4];       /* number of bytes per page */
-  char_u b0_mtime[4];           /* last modification time of file */
-  char_u b0_ino[4];             /* inode of b0_fname */
-  char_u b0_pid[4];             /* process id of creator (or 0) */
-  char_u b0_uname[B0_UNAME_SIZE];        /* name of user (uid if no name) */
-  char_u b0_hname[B0_HNAME_SIZE];        /* host name (if it has a name) */
-  char_u b0_fname[B0_FNAME_SIZE_ORG];        /* name of file being edited */
-  long b0_magic_long;           /* check for byte order of long */
-  int b0_magic_int;             /* check for byte order of int */
-  short b0_magic_short;         /* check for byte order of short */
-  char_u b0_magic_char;         /* check for last char */
-};
-
-/*
- * Note: b0_dirty and b0_flags are put at the end of the file name.  For very
- * long file names in older versions of Vim they are invalid.
- * The 'fileencoding' comes before b0_flags, with a NUL in front.  But only
- * when there is room, for very long file names it's omitted.
- */
-#define B0_DIRTY        0x55
-#define b0_dirty        b0_fname[B0_FNAME_SIZE_ORG - 1]
-
-/*
- * The b0_flags field is new in Vim 7.0.
- */
-#define b0_flags        b0_fname[B0_FNAME_SIZE_ORG - 2]
-
-/*
- * Crypt seed goes here, 8 bytes.  New in Vim 7.3.
- * Without encryption these bytes may be used for 'fenc'.
- */
-#define b0_seed         b0_fname[B0_FNAME_SIZE_ORG - 2 - MF_SEED_LEN]
-
-/* The lowest two bits contain the fileformat.  Zero means it's not set
- * (compatible with Vim 6.x), otherwise it's EOL_UNIX + 1, EOL_DOS + 1 or
- * EOL_MAC + 1. */
-#define B0_FF_MASK      3
-
-/* Swap file is in directory of edited file.  Used to find the file from
- * different mount points. */
-#define B0_SAME_DIR     4
-
-/* The 'fileencoding' is at the end of b0_fname[], with a NUL in front of it.
- * When empty there is only the NUL. */
-#define B0_HAS_FENC     8
-
-#define STACK_INCR      5       /* nr of entries added to ml_stack at a time */
-
-/*
- * The line number where the first mark may be is remembered.
- * If it is 0 there are no marks at all.
- * (always used for the current buffer only, no buffer change possible while
- * executing a global command).
- */
-static linenr_T lowest_marked = 0;
-
-/*
- * arguments for ml_find_line()
- */
-#define ML_DELETE       0x11        /* delete line */
-#define ML_INSERT       0x12        /* insert line */
-#define ML_FIND         0x13        /* just find the line */
-#define ML_FLUSH        0x02        /* flush locked block */
-#define ML_SIMPLE(x)    (x & 0x10)  /* DEL, INS or FIND */
-
-/* argument for ml_upd_block0() */
-typedef enum {
-  UB_FNAME = 0          /* update timestamp and filename */
-  , UB_SAME_DIR         /* update the B0_SAME_DIR flag */
-  , UB_CRYPT            /* update crypt key */
-} upd_block0_T;
-
-static void ml_set_b0_crypt(buf_T *buf, ZERO_BL *b0p);
-static int ml_check_b0_id(ZERO_BL *b0p);
-static void ml_upd_block0(buf_T *buf, upd_block0_T what);
-static void set_b0_fname(ZERO_BL *, buf_T *buf);
-static void set_b0_dir_flag(ZERO_BL *b0p, buf_T *buf);
-static void add_b0_fenc(ZERO_BL *b0p, buf_T *buf);
-static time_t swapfile_info(char_u *);
-static int recov_file_names(char_u **, char_u *, int prepend_dot);
-static int ml_append_int(buf_T *, linenr_T, char_u *, colnr_T, int, int);
-static int ml_delete_int(buf_T *, linenr_T, int);
-static char_u *findswapname(buf_T *, char_u **, char_u *);
-static void ml_flush_line(buf_T *);
-static bhdr_T *ml_new_data(memfile_T *, int, int);
-static bhdr_T *ml_new_ptr(memfile_T *);
-static bhdr_T *ml_find_line(buf_T *, linenr_T, int);
-static int ml_add_stack(buf_T *);
-static void ml_lineadd(buf_T *, int);
-static int b0_magic_wrong(ZERO_BL *);
-#ifdef CHECK_INODE
-static int fnamecmp_ino(char_u *, char_u *, long);
-#endif
-static void long_to_char(long, char_u *);
-static long char_to_long(char_u *);
-#if defined(UNIX) || defined(WIN3264)
-static char_u *make_percent_swname(char_u *dir, char_u *name);
-#endif
-static void ml_crypt_prepare(memfile_T *mfp, off_t offset, int reading);
-static void ml_updatechunk(buf_T *buf, long line, long len, int updtype);
-
-/*
- * Open a new memline for "buf".
- *
- * Return FAIL for failure, OK otherwise.
- */
-int ml_open(buf_T *buf)
-{
-  memfile_T   *mfp;
-  bhdr_T      *hp = NULL;
-  ZERO_BL     *b0p;
-  PTR_BL      *pp;
-  DATA_BL     *dp;
-
-  /*
-   * init fields in memline struct
-   */
-  buf->b_ml.ml_stack_size = 0;   /* no stack yet */
-  buf->b_ml.ml_stack = NULL;    /* no stack yet */
-  buf->b_ml.ml_stack_top = 0;   /* nothing in the stack */
-  buf->b_ml.ml_locked = NULL;   /* no cached block */
-  buf->b_ml.ml_line_lnum = 0;   /* no cached line */
-  buf->b_ml.ml_chunksize = NULL;
-
-  if (cmdmod.noswapfile) {
-    buf->b_p_swf = FALSE;
-  }
-
-  /*
-   * When 'updatecount' is non-zero swap file may be opened later.
-   */
-  if (p_uc && buf->b_p_swf)
-    buf->b_may_swap = TRUE;
-  else
-    buf->b_may_swap = FALSE;
-
-  /*
-   * Open the memfile.  No swap file is created yet.
-   */
-  mfp = mf_open(NULL, 0);
-  if (mfp == NULL)
-    goto error;
-
-  buf->b_ml.ml_mfp = mfp;
-  mfp->mf_buffer = buf;
-  buf->b_ml.ml_flags = ML_EMPTY;
-  buf->b_ml.ml_line_count = 1;
-  curwin->w_nrwidth_line_count = 0;
-
-
-  /*
-   * fill block0 struct and write page 0
-   */
-  if ((hp = mf_new(mfp, FALSE, 1)) == NULL)
-    goto error;
-  if (hp->bh_bnum != 0) {
-    EMSG(_("E298: Didn't get block nr 0?"));
-    goto error;
-  }
-  b0p = (ZERO_BL *)(hp->bh_data);
-
-  b0p->b0_id[0] = BLOCK0_ID0;
-  b0p->b0_id[1] = BLOCK0_ID1;
-  b0p->b0_magic_long = (long)B0_MAGIC_LONG;
-  b0p->b0_magic_int = (int)B0_MAGIC_INT;
-  b0p->b0_magic_short = (short)B0_MAGIC_SHORT;
-  b0p->b0_magic_char = B0_MAGIC_CHAR;
-  STRNCPY(b0p->b0_version, "VIM ", 4);
-  STRNCPY(b0p->b0_version + 4, Version, 6);
-  long_to_char((long)mfp->mf_page_size, b0p->b0_page_size);
-
-  if (!buf->b_spell) {
-    b0p->b0_dirty = buf->b_changed ? B0_DIRTY : 0;
-    b0p->b0_flags = get_fileformat(buf) + 1;
-    set_b0_fname(b0p, buf);
-    (void)os_get_user_name((char *)b0p->b0_uname, B0_UNAME_SIZE);
-    b0p->b0_uname[B0_UNAME_SIZE - 1] = NUL;
-    os_get_hostname((char *)b0p->b0_hname, B0_HNAME_SIZE);
-    b0p->b0_hname[B0_HNAME_SIZE - 1] = NUL;
-    long_to_char(os_get_pid(), b0p->b0_pid);
-    if (*buf->b_p_key != NUL)
-      ml_set_b0_crypt(buf, b0p);
-  }
-
-  /*
-   * Always sync block number 0 to disk, so we can check the file name in
-   * the swap file in findswapname(). Don't do this for a help files or
-   * a spell buffer though.
-   * Only works when there's a swapfile, otherwise it's done when the file
-   * is created.
-   */
-  mf_put(mfp, hp, TRUE, FALSE);
-  if (!buf->b_help && !B_SPELL(buf))
-    (void)mf_sync(mfp, 0);
-
-  /*
-   * Fill in root pointer block and write page 1.
-   */
-  if ((hp = ml_new_ptr(mfp)) == NULL)
-    goto error;
-  if (hp->bh_bnum != 1) {
-    EMSG(_("E298: Didn't get block nr 1?"));
-    goto error;
-  }
-  pp = (PTR_BL *)(hp->bh_data);
-  pp->pb_count = 1;
-  pp->pb_pointer[0].pe_bnum = 2;
-  pp->pb_pointer[0].pe_page_count = 1;
-  pp->pb_pointer[0].pe_old_lnum = 1;
-  pp->pb_pointer[0].pe_line_count = 1;      /* line count after insertion */
-  mf_put(mfp, hp, TRUE, FALSE);
-
-  /*
-   * Allocate first data block and create an empty line 1.
-   */
-  if ((hp = ml_new_data(mfp, FALSE, 1)) == NULL)
-    goto error;
-  if (hp->bh_bnum != 2) {
-    EMSG(_("E298: Didn't get block nr 2?"));
-    goto error;
-  }
-
-  dp = (DATA_BL *)(hp->bh_data);
-  dp->db_index[0] = --dp->db_txt_start;         /* at end of block */
-  dp->db_free -= 1 + INDEX_SIZE;
-  dp->db_line_count = 1;
-  *((char_u *)dp + dp->db_txt_start) = NUL;     /* empty line */
-
-  return OK;
-
-error:
-  if (mfp != NULL) {
-    if (hp)
-      mf_put(mfp, hp, FALSE, FALSE);
-    mf_close(mfp, TRUE);            /* will also free(mfp->mf_fname) */
-  }
-  buf->b_ml.ml_mfp = NULL;
-  return FAIL;
-}
-
-/*
- * Prepare encryption for "buf" with block 0 "b0p".
- */
-static void ml_set_b0_crypt(buf_T *buf, ZERO_BL *b0p)
-{
-  if (*buf->b_p_key == NUL)
-    b0p->b0_id[1] = BLOCK0_ID1;
-  else {
-    if (get_crypt_method(buf) == 0)
-      b0p->b0_id[1] = BLOCK0_ID1_C0;
-    else {
-      b0p->b0_id[1] = BLOCK0_ID1_C1;
-      /* Generate a seed and store it in block 0 and in the memfile. */
-      sha2_seed(&b0p->b0_seed, MF_SEED_LEN, NULL, 0);
-      memmove(buf->b_ml.ml_mfp->mf_seed, &b0p->b0_seed, MF_SEED_LEN);
-    }
-  }
-}
-
-/*
- * Called after the crypt key or 'cryptmethod' was changed for "buf".
- * Will apply this to the swapfile.
- * "old_key" is the previous key.  It is equal to buf->b_p_key when
- * 'cryptmethod' is changed.
- * "old_cm" is the previous 'cryptmethod'.  It is equal to the current
- * 'cryptmethod' when 'key' is changed.
- */
-void ml_set_crypt_key(buf_T *buf, char_u *old_key, int old_cm)
-{
-  memfile_T   *mfp = buf->b_ml.ml_mfp;
-  bhdr_T      *hp;
-  int page_count;
-  int idx;
-  long error;
-  infoptr_T   *ip;
-  PTR_BL      *pp;
-  DATA_BL     *dp;
-  blocknr_T bnum;
-  int top;
-
-  if (mfp == NULL)
-    return;      /* no memfile yet, nothing to do */
-
-  /* Set the key, method and seed to be used for reading, these must be the
-   * old values. */
-  mfp->mf_old_key = old_key;
-  mfp->mf_old_cm = old_cm;
-  if (old_cm > 0)
-    memmove(mfp->mf_old_seed, mfp->mf_seed, MF_SEED_LEN);
-
-  /* Update block 0 with the crypt flag and may set a new seed. */
-  ml_upd_block0(buf, UB_CRYPT);
-
-  if (mfp->mf_infile_count > 2) {
-    /*
-     * Need to read back all data blocks from disk, decrypt them with the
-     * old key/method and mark them to be written. The algorithm is
-     * similar to what happens in ml_recover(), but we skip negative block
-     * numbers.
-     */
-    ml_flush_line(buf);                     /* flush buffered line */
-    (void)ml_find_line(buf, (linenr_T)0, ML_FLUSH);     /* flush locked block */
-
-    hp = NULL;
-    bnum = 1;                   /* start with block 1 */
-    page_count = 1;             /* which is 1 page */
-    idx = 0;                    /* start with first index in block 1 */
-    error = 0;
-    buf->b_ml.ml_stack_top = 0;
-    free(buf->b_ml.ml_stack);
-    buf->b_ml.ml_stack = NULL;
-    buf->b_ml.ml_stack_size = 0;        /* no stack yet */
-
-    for (; !got_int; line_breakcheck()) {
-      if (hp != NULL)
-        mf_put(mfp, hp, FALSE, FALSE);          /* release previous block */
-
-      /* get the block (pointer or data) */
-      if ((hp = mf_get(mfp, (blocknr_T)bnum, page_count)) == NULL) {
-        if (bnum == 1)
-          break;
-        ++error;
-      } else {
-        pp = (PTR_BL *)(hp->bh_data);
-        if (pp->pb_id == PTR_ID) {              /* it is a pointer block */
-          if (pp->pb_count == 0) {
-            /* empty block? */
-            ++error;
-          } else if (idx < (int)pp->pb_count) {       /* go a block deeper */
-            if (pp->pb_pointer[idx].pe_bnum < 0) {
-              /* Skip data block with negative block number. */
-              ++idx;                  /* get same block again for next index */
-              continue;
-            }
-
-            /* going one block deeper in the tree, new entry in
-             * stack */
-            top = ml_add_stack(buf);
-            ip = &(buf->b_ml.ml_stack[top]);
-            ip->ip_bnum = bnum;
-            ip->ip_index = idx;
-
-            bnum = pp->pb_pointer[idx].pe_bnum;
-            page_count = pp->pb_pointer[idx].pe_page_count;
-            continue;
-          }
-        } else {          /* not a pointer block */
-          dp = (DATA_BL *)(hp->bh_data);
-          if (dp->db_id != DATA_ID)             /* block id wrong */
-            ++error;
-          else {
-            /* It is a data block, need to write it back to disk. */
-            mf_put(mfp, hp, TRUE, FALSE);
-            hp = NULL;
-          }
-        }
-      }
-
-      if (buf->b_ml.ml_stack_top == 0)          /* finished */
-        break;
-
-      /* go one block up in the tree */
-      ip = &(buf->b_ml.ml_stack[--(buf->b_ml.ml_stack_top)]);
-      bnum = ip->ip_bnum;
-      idx = ip->ip_index + 1;               /* go to next index */
-      page_count = 1;
-    }
-
-    if (error > 0)
-      EMSG(_("E843: Error while updating swap file crypt"));
-  }
-
-  mfp->mf_old_key = NULL;
-}
-
-/*
- * ml_setname() is called when the file name of "buf" has been changed.
- * It may rename the swap file.
- */
-void ml_setname(buf_T *buf)
-{
-  int success = FALSE;
-  memfile_T   *mfp;
-  char_u      *fname;
-  char_u      *dirp;
-
-  mfp = buf->b_ml.ml_mfp;
-  if (mfp->mf_fd < 0) {             /* there is no swap file yet */
-    /*
-     * When 'updatecount' is 0 and 'noswapfile' there is no swap file.
-     * For help files we will make a swap file now.
-     */
-    if (p_uc != 0 && !cmdmod.noswapfile) {
-      ml_open_file(buf); /* create a swap file */
-    }
-    return;
-  }
-
-  /*
-   * Try all directories in the 'directory' option.
-   */
-  dirp = p_dir;
-  for (;; ) {
-    if (*dirp == NUL)               /* tried all directories, fail */
-      break;
-    fname = findswapname(buf, &dirp, mfp->mf_fname);
-    /* alloc's fname */
-    if (dirp == NULL)               /* out of memory */
-      break;
-    if (fname == NULL)              /* no file name found for this dir */
-      continue;
-
-    /* if the file name is the same we don't have to do anything */
-    if (fnamecmp(fname, mfp->mf_fname) == 0) {
-      free(fname);
-      success = TRUE;
-      break;
-    }
-    /* need to close the swap file before renaming */
-    if (mfp->mf_fd >= 0) {
-      close(mfp->mf_fd);
-      mfp->mf_fd = -1;
-    }
-
-    /* try to rename the swap file */
-    if (vim_rename(mfp->mf_fname, fname) == 0) {
-      success = TRUE;
-      free(mfp->mf_fname);
-      mfp->mf_fname = fname;
-      free(mfp->mf_ffname);
-      mf_set_ffname(mfp);
-      ml_upd_block0(buf, UB_SAME_DIR);
-      break;
-    }
-    free(fname);                /* this fname didn't work, try another */
-  }
-
-  if (mfp->mf_fd == -1) {           /* need to (re)open the swap file */
-    mfp->mf_fd = mch_open((char *)mfp->mf_fname, O_RDWR, 0);
-    if (mfp->mf_fd < 0) {
-      /* could not (re)open the swap file, what can we do???? */
-      EMSG(_("E301: Oops, lost the swap file!!!"));
-      return;
-    }
-#ifdef HAVE_FD_CLOEXEC
-    {
-      int fdflags = fcntl(mfp->mf_fd, F_GETFD);
-      if (fdflags >= 0 && (fdflags & FD_CLOEXEC) == 0)
-        fcntl(mfp->mf_fd, F_SETFD, fdflags | FD_CLOEXEC);
-    }
-#endif
-  }
-  if (!success)
-    EMSG(_("E302: Could not rename swap file"));
-}
-
-/*
- * Open a file for the memfile for all buffers that are not readonly or have
- * been modified.
- * Used when 'updatecount' changes from zero to non-zero.
- */
-void ml_open_files(void)
-{
-  buf_T       *buf;
-
-  for (buf = firstbuf; buf != NULL; buf = buf->b_next)
-    if (!buf->b_p_ro || buf->b_changed)
-      ml_open_file(buf);
-}
-
-/*
- * Open a swap file for an existing memfile, if there is no swap file yet.
- * If we are unable to find a file name, mf_fname will be NULL
- * and the memfile will be in memory only (no recovery possible).
- */
-void ml_open_file(buf_T *buf)
-{
-  memfile_T   *mfp;
-  char_u      *fname;
-  char_u      *dirp;
-
-  mfp = buf->b_ml.ml_mfp;
-  if (mfp == NULL || mfp->mf_fd >= 0 || !buf->b_p_swf || cmdmod.noswapfile) {
-    return; /* nothing to do */
-  }
-
-  /* For a spell buffer use a temp file name. */
-  if (buf->b_spell) {
-    fname = vim_tempname('s');
-    if (fname != NULL)
-      (void)mf_open_file(mfp, fname);           /* consumes fname! */
-    buf->b_may_swap = FALSE;
-    return;
-  }
-
-  /*
-   * Try all directories in 'directory' option.
-   */
-  dirp = p_dir;
-  for (;; ) {
-    if (*dirp == NUL)
-      break;
-    /* There is a small chance that between choosing the swap file name
-     * and creating it, another Vim creates the file.  In that case the
-     * creation will fail and we will use another directory. */
-    fname = findswapname(buf, &dirp, NULL);     /* allocates fname */
-    if (dirp == NULL)
-      break;        /* out of memory */
-    if (fname == NULL)
-      continue;
-    if (mf_open_file(mfp, fname) == OK) {       /* consumes fname! */
-      ml_upd_block0(buf, UB_SAME_DIR);
-
-      /* Flush block zero, so others can read it */
-      if (mf_sync(mfp, MFS_ZERO) == OK) {
-        /* Mark all blocks that should be in the swapfile as dirty.
-         * Needed for when the 'swapfile' option was reset, so that
-         * the swap file was deleted, and then on again. */
-        mf_set_dirty(mfp);
-        break;
-      }
-      /* Writing block 0 failed: close the file and try another dir */
-      mf_close_file(buf, FALSE);
-    }
-  }
-
-  if (mfp->mf_fname == NULL) {          /* Failed! */
-    need_wait_return = TRUE;            /* call wait_return later */
-    ++no_wait_return;
-    (void)EMSG2(_(
-            "E303: Unable to open swap file for \"%s\", recovery impossible"),
-        buf_spname(buf) != NULL ? buf_spname(buf) : buf->b_fname);
-    --no_wait_return;
-  }
-
-  /* don't try to open a swap file again */
-  buf->b_may_swap = FALSE;
-}
-
-/*
- * If still need to create a swap file, and starting to edit a not-readonly
- * file, or reading into an existing buffer, create a swap file now.
- */
-void 
-check_need_swap (
-    int newfile                    /* reading file into new buffer */
-)
-{
-  if (curbuf->b_may_swap && (!curbuf->b_p_ro || !newfile))
-    ml_open_file(curbuf);
-}
-
-/*
- * Close memline for buffer 'buf'.
- * If 'del_file' is TRUE, delete the swap file
- */
-void ml_close(buf_T *buf, int del_file)
-{
-  if (buf->b_ml.ml_mfp == NULL)                 /* not open */
-    return;
-  mf_close(buf->b_ml.ml_mfp, del_file);         /* close the .swp file */
-  if (buf->b_ml.ml_line_lnum != 0 && (buf->b_ml.ml_flags & ML_LINE_DIRTY))
-    free(buf->b_ml.ml_line_ptr);
-  free(buf->b_ml.ml_stack);
-  free(buf->b_ml.ml_chunksize);
-  buf->b_ml.ml_chunksize = NULL;
-  buf->b_ml.ml_mfp = NULL;
-
-  /* Reset the "recovered" flag, give the ATTENTION prompt the next time
-   * this buffer is loaded. */
-  buf->b_flags &= ~BF_RECOVERED;
-}
-
-/*
- * Close all existing memlines and memfiles.
- * Only used when exiting.
- * When 'del_file' is TRUE, delete the memfiles.
- * But don't delete files that were ":preserve"d when we are POSIX compatible.
- */
-void ml_close_all(int del_file)
-{
-  buf_T       *buf;
-
-  for (buf = firstbuf; buf != NULL; buf = buf->b_next)
-    ml_close(buf, del_file && ((buf->b_flags & BF_PRESERVED) == 0
-                               || vim_strchr(p_cpo, CPO_PRESERVE) == NULL));
-  spell_delete_wordlist();      /* delete the internal wordlist */
-#ifdef TEMPDIRNAMES
-  vim_deltempdir();             /* delete created temp directory */
-#endif
-}
-
-/*
- * Close all memfiles for not modified buffers.
- * Only use just before exiting!
- */
-void ml_close_notmod(void)
-{
-  buf_T       *buf;
-
-  for (buf = firstbuf; buf != NULL; buf = buf->b_next)
-    if (!bufIsChanged(buf))
-      ml_close(buf, TRUE);          /* close all not-modified buffers */
-}
-
-/*
- * Update the timestamp in the .swp file.
- * Used when the file has been written.
- */
-void ml_timestamp(buf_T *buf)
-{
-  ml_upd_block0(buf, UB_FNAME);
-}
-
-/*
- * Return FAIL when the ID of "b0p" is wrong.
- */
-static int ml_check_b0_id(ZERO_BL *b0p)
-{
-  if (b0p->b0_id[0] != BLOCK0_ID0
-      || (b0p->b0_id[1] != BLOCK0_ID1
-          && b0p->b0_id[1] != BLOCK0_ID1_C0
-          && b0p->b0_id[1] != BLOCK0_ID1_C1)
-      )
-    return FAIL;
-  return OK;
-}
-
-/*
- * Update the timestamp or the B0_SAME_DIR flag of the .swp file.
- */
-static void ml_upd_block0(buf_T *buf, upd_block0_T what)
-{
-  memfile_T   *mfp;
-  bhdr_T      *hp;
-  ZERO_BL     *b0p;
-
-  mfp = buf->b_ml.ml_mfp;
-  if (mfp == NULL || (hp = mf_get(mfp, (blocknr_T)0, 1)) == NULL)
-    return;
-  b0p = (ZERO_BL *)(hp->bh_data);
-  if (ml_check_b0_id(b0p) == FAIL)
-    EMSG(_("E304: ml_upd_block0(): Didn't get block 0??"));
-  else {
-    if (what == UB_FNAME)
-      set_b0_fname(b0p, buf);
-    else if (what == UB_CRYPT)
-      ml_set_b0_crypt(buf, b0p);
-    else     /* what == UB_SAME_DIR */
-      set_b0_dir_flag(b0p, buf);
-  }
-  mf_put(mfp, hp, TRUE, FALSE);
-}
-
-/*
- * Write file name and timestamp into block 0 of a swap file.
- * Also set buf->b_mtime.
- * Don't use NameBuff[]!!!
- */
-static void set_b0_fname(ZERO_BL *b0p, buf_T *buf)
-{
-  if (buf->b_ffname == NULL)
-    b0p->b0_fname[0] = NUL;
-  else {
-    char uname[B0_UNAME_SIZE];
-
-    /*
-     * For a file under the home directory of the current user, we try to
-     * replace the home directory path with "~user". This helps when
-     * editing the same file on different machines over a network.
-     * First replace home dir path with "~/" with home_replace().
-     * Then insert the user name to get "~user/".
-     */
-    home_replace(NULL, buf->b_ffname, b0p->b0_fname,
-        B0_FNAME_SIZE_CRYPT, TRUE);
-    if (b0p->b0_fname[0] == '~') {
-      /* If there is no user name or it is too long, don't use "~/" */
-      int retval = os_get_user_name(uname, B0_UNAME_SIZE);
-      size_t ulen = STRLEN(uname);
-      size_t flen = STRLEN(b0p->b0_fname);
-      if (retval == FAIL || ulen + flen > B0_FNAME_SIZE_CRYPT - 1) {
-        vim_strncpy(b0p->b0_fname, buf->b_ffname,
-            B0_FNAME_SIZE_CRYPT - 1);
-      } else {
-        memmove(b0p->b0_fname + ulen + 1, b0p->b0_fname + 1, flen);
-        memmove(b0p->b0_fname + 1, uname, ulen);
-      }
-    }
-    FileInfo file_info;
-    if (os_get_file_info((char *)buf->b_ffname, &file_info)) {
-      long_to_char((long)file_info.stat.st_mtim.tv_sec, b0p->b0_mtime);
-#ifdef CHECK_INODE
-      long_to_char((long)file_info.stat.st_ino, b0p->b0_ino);
-#endif
-      buf_store_file_info(buf, &file_info);
-      buf->b_mtime_read = buf->b_mtime;
-    } else {
-      long_to_char(0L, b0p->b0_mtime);
-#ifdef CHECK_INODE
-      long_to_char(0L, b0p->b0_ino);
-#endif
-      buf->b_mtime = 0;
-      buf->b_mtime_read = 0;
-      buf->b_orig_size = 0;
-      buf->b_orig_mode = 0;
-    }
-  }
-
-  /* Also add the 'fileencoding' if there is room. */
-  add_b0_fenc(b0p, curbuf);
-}
-
-/*
- * Update the B0_SAME_DIR flag of the swap file.  It's set if the file and the
- * swapfile for "buf" are in the same directory.
- * This is fail safe: if we are not sure the directories are equal the flag is
- * not set.
- */
-static void set_b0_dir_flag(ZERO_BL *b0p, buf_T *buf)
-{
-  if (same_directory(buf->b_ml.ml_mfp->mf_fname, buf->b_ffname))
-    b0p->b0_flags |= B0_SAME_DIR;
-  else
-    b0p->b0_flags &= ~B0_SAME_DIR;
-}
-
-/*
- * When there is room, add the 'fileencoding' to block zero.
- */
-static void add_b0_fenc(ZERO_BL *b0p, buf_T *buf)
-{
-  int n;
-  int size = B0_FNAME_SIZE_NOCRYPT;
-
-  /* Without encryption use the same offset as in Vim 7.2 to be compatible.
-   * With encryption it's OK to move elsewhere, the swap file is not
-   * compatible anyway. */
-  if (*buf->b_p_key != NUL)
-    size = B0_FNAME_SIZE_CRYPT;
-
-  n = (int)STRLEN(buf->b_p_fenc);
-  if ((int)STRLEN(b0p->b0_fname) + n + 1 > size)
-    b0p->b0_flags &= ~B0_HAS_FENC;
-  else {
-    memmove((char *)b0p->b0_fname + size - n,
-        (char *)buf->b_p_fenc, (size_t)n);
-    *(b0p->b0_fname + size - n - 1) = NUL;
-    b0p->b0_flags |= B0_HAS_FENC;
-  }
-}
-
-
-/*
- * Try to recover curbuf from the .swp file.
- */
-void ml_recover(void)
-{
-  buf_T       *buf = NULL;
-  memfile_T   *mfp = NULL;
-  char_u      *fname;
-  char_u      *fname_used = NULL;
-  bhdr_T      *hp = NULL;
-  ZERO_BL     *b0p;
-  int b0_ff;
-  char_u      *b0_fenc = NULL;
-  int b0_cm = -1;
-  PTR_BL      *pp;
-  DATA_BL     *dp;
-  infoptr_T   *ip;
-  blocknr_T bnum;
-  int page_count;
-  int len;
-  int directly;
-  linenr_T lnum;
-  char_u      *p;
-  int i;
-  long error;
-  int cannot_open;
-  linenr_T line_count;
-  int has_error;
-  int idx;
-  int top;
-  int txt_start;
-  off_t size;
-  int called_from_main;
-  int serious_error = TRUE;
-  long mtime;
-  int attr;
-  int orig_file_status = NOTDONE;
-
-  recoverymode = TRUE;
-  called_from_main = (curbuf->b_ml.ml_mfp == NULL);
-  attr = hl_attr(HLF_E);
-
-  /*
-   * If the file name ends in ".s[uvw][a-z]" we assume this is the swap file.
-   * Otherwise a search is done to find the swap file(s).
-   */
-  fname = curbuf->b_fname;
-  if (fname == NULL)                /* When there is no file name */
-    fname = (char_u *)"";
-  len = (int)STRLEN(fname);
-  if (len >= 4 &&
-      STRNICMP(fname + len - 4, ".s", 2)
-      == 0
-      && vim_strchr((char_u *)"UVWuvw", fname[len - 2]) != NULL
-      && ASCII_ISALPHA(fname[len - 1])) {
-    directly = TRUE;
-    fname_used = vim_strsave(fname);     /* make a copy for mf_open() */
-  } else {
-    directly = FALSE;
-
-    /* count the number of matching swap files */
-    len = recover_names(fname, FALSE, 0, NULL);
-    if (len == 0) {                 /* no swap files found */
-      EMSG2(_("E305: No swap file found for %s"), fname);
-      goto theend;
-    }
-    if (len == 1)                   /* one swap file found, use it */
-      i = 1;
-    else {                          /* several swap files found, choose */
-      /* list the names of the swap files */
-      (void)recover_names(fname, TRUE, 0, NULL);
-      msg_putchar('\n');
-      MSG_PUTS(_("Enter number of swap file to use (0 to quit): "));
-      i = get_number(FALSE, NULL);
-      if (i < 1 || i > len)
-        goto theend;
-    }
-    /* get the swap file name that will be used */
-    (void)recover_names(fname, FALSE, i, &fname_used);
-  }
-  if (fname_used == NULL)
-    goto theend;                        /* out of memory */
-
-  /* When called from main() still need to initialize storage structure */
-  if (called_from_main && ml_open(curbuf) == FAIL)
-    getout(1);
-
-  /*
-   * Allocate a buffer structure for the swap file that is used for recovery.
-   * Only the memline and crypt information in it are really used.
-   */
-  buf = (buf_T *)alloc((unsigned)sizeof(buf_T));
-
-  /*
-   * init fields in memline struct
-   */
-  buf->b_ml.ml_stack_size = 0;          /* no stack yet */
-  buf->b_ml.ml_stack = NULL;            /* no stack yet */
-  buf->b_ml.ml_stack_top = 0;           /* nothing in the stack */
-  buf->b_ml.ml_line_lnum = 0;           /* no cached line */
-  buf->b_ml.ml_locked = NULL;           /* no locked block */
-  buf->b_ml.ml_flags = 0;
-  buf->b_p_key = empty_option;
-  buf->b_p_cm = empty_option;
-
-  /*
-   * open the memfile from the old swap file
-   */
-  p = vim_strsave(fname_used);   /* save "fname_used" for the message:
-                                    mf_open() will consume "fname_used"! */
-  mfp = mf_open(fname_used, O_RDONLY);
-  fname_used = p;
-  if (mfp == NULL || mfp->mf_fd < 0) {
-    if (fname_used != NULL)
-      EMSG2(_("E306: Cannot open %s"), fname_used);
-    goto theend;
-  }
-  buf->b_ml.ml_mfp = mfp;
-  mfp->mf_buffer = buf;
-
-  /*
-   * The page size set in mf_open() might be different from the page size
-   * used in the swap file, we must get it from block 0.  But to read block
-   * 0 we need a page size.  Use the minimal size for block 0 here, it will
-   * be set to the real value below.
-   */
-  mfp->mf_page_size = MIN_SWAP_PAGE_SIZE;
-
-  /*
-   * try to read block 0
-   */
-  if ((hp = mf_get(mfp, (blocknr_T)0, 1)) == NULL) {
-    msg_start();
-    MSG_PUTS_ATTR(_("Unable to read block 0 from "), attr | MSG_HIST);
-    msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
-    MSG_PUTS_ATTR(_(
-            "\nMaybe no changes were made or Vim did not update the swap file."),
-        attr | MSG_HIST);
-    msg_end();
-    goto theend;
-  }
-  b0p = (ZERO_BL *)(hp->bh_data);
-  if (STRNCMP(b0p->b0_version, "VIM 3.0", 7) == 0) {
-    msg_start();
-    msg_outtrans_attr(mfp->mf_fname, MSG_HIST);
-    MSG_PUTS_ATTR(_(" cannot be used with this version of Vim.\n"),
-        MSG_HIST);
-    MSG_PUTS_ATTR(_("Use Vim version 3.0.\n"), MSG_HIST);
-    msg_end();
-    goto theend;
-  }
-  if (ml_check_b0_id(b0p) == FAIL) {
-    EMSG2(_("E307: %s does not look like a Vim swap file"), mfp->mf_fname);
-    goto theend;
-  }
-  if (b0_magic_wrong(b0p)) {
-    msg_start();
-    msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
-    MSG_PUTS_ATTR(_(" cannot be used on this computer.\n"),
-        attr | MSG_HIST);
-    MSG_PUTS_ATTR(_("The file was created on "), attr | MSG_HIST);
-    /* avoid going past the end of a corrupted hostname */
-    b0p->b0_fname[0] = NUL;
-    MSG_PUTS_ATTR(b0p->b0_hname, attr | MSG_HIST);
-    MSG_PUTS_ATTR(_(",\nor the file has been damaged."), attr | MSG_HIST);
-    msg_end();
-    goto theend;
-  }
-
-  if (b0p->b0_id[1] == BLOCK0_ID1_C0)
-    b0_cm = 0;
-  else if (b0p->b0_id[1] == BLOCK0_ID1_C1) {
-    b0_cm = 1;
-    memmove(mfp->mf_seed, &b0p->b0_seed, MF_SEED_LEN);
-  }
-  set_crypt_method(buf, b0_cm);
-
-  /*
-   * If we guessed the wrong page size, we have to recalculate the
-   * highest block number in the file.
-   */
-  if (mfp->mf_page_size != (unsigned)char_to_long(b0p->b0_page_size)) {
-    unsigned previous_page_size = mfp->mf_page_size;
-
-    mf_new_page_size(mfp, (unsigned)char_to_long(b0p->b0_page_size));
-    if (mfp->mf_page_size < previous_page_size) {
-      msg_start();
-      msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
-      MSG_PUTS_ATTR(_(
-              " has been damaged (page size is smaller than minimum value).\n"),
-          attr | MSG_HIST);
-      msg_end();
-      goto theend;
-    }
-    if ((size = lseek(mfp->mf_fd, (off_t)0L, SEEK_END)) <= 0)
-      mfp->mf_blocknr_max = 0;              /* no file or empty file */
-    else
-      mfp->mf_blocknr_max = (blocknr_T)(size / mfp->mf_page_size);
-    mfp->mf_infile_count = mfp->mf_blocknr_max;
-
-    /* need to reallocate the memory used to store the data */
-    p = alloc(mfp->mf_page_size);
-    memmove(p, hp->bh_data, previous_page_size);
-    free(hp->bh_data);
-    hp->bh_data = p;
-    b0p = (ZERO_BL *)(hp->bh_data);
-  }
-
-  /*
-   * If .swp file name given directly, use name from swap file for buffer.
-   */
-  if (directly) {
-    expand_env(b0p->b0_fname, NameBuff, MAXPATHL);
-    if (setfname(curbuf, NameBuff, NULL, TRUE) == FAIL)
-      goto theend;
-  }
-
-  home_replace(NULL, mfp->mf_fname, NameBuff, MAXPATHL, TRUE);
-  smsg((char_u *)_("Using swap file \"%s\""), NameBuff);
-
-  if (buf_spname(curbuf) != NULL)
-    vim_strncpy(NameBuff, buf_spname(curbuf), MAXPATHL - 1);
-  else
-    home_replace(NULL, curbuf->b_ffname, NameBuff, MAXPATHL, TRUE);
-  smsg((char_u *)_("Original file \"%s\""), NameBuff);
-  msg_putchar('\n');
-
-  /*
-   * check date of swap file and original file
-   */
-  FileInfo org_file_info;
-  FileInfo swp_file_info;
-  mtime = char_to_long(b0p->b0_mtime);
-  if (curbuf->b_ffname != NULL
-      && os_get_file_info((char *)curbuf->b_ffname, &org_file_info)
-      && ((os_get_file_info((char *)mfp->mf_fname, &swp_file_info)
-           && org_file_info.stat.st_mtim.tv_sec
-              > swp_file_info.stat.st_mtim.tv_sec)
-          || org_file_info.stat.st_mtim.tv_sec != mtime)) {
-    EMSG(_("E308: Warning: Original file may have been changed"));
-  }
-  out_flush();
-
-  /* Get the 'fileformat' and 'fileencoding' from block zero. */
-  b0_ff = (b0p->b0_flags & B0_FF_MASK);
-  if (b0p->b0_flags & B0_HAS_FENC) {
-    int fnsize = B0_FNAME_SIZE_NOCRYPT;
-
-    /* Use the same size as in add_b0_fenc(). */
-    if (b0p->b0_id[1] != BLOCK0_ID1)
-      fnsize = B0_FNAME_SIZE_CRYPT;
-    for (p = b0p->b0_fname + fnsize; p > b0p->b0_fname && p[-1] != NUL; --p)
-      ;
-    b0_fenc = vim_strnsave(p, (int)(b0p->b0_fname + fnsize - p));
-  }
-
-  mf_put(mfp, hp, FALSE, FALSE);        /* release block 0 */
-  hp = NULL;
-
-  /*
-   * Now that we are sure that the file is going to be recovered, clear the
-   * contents of the current buffer.
-   */
-  while (!(curbuf->b_ml.ml_flags & ML_EMPTY))
-    ml_delete((linenr_T)1, FALSE);
-
-  /*
-   * Try reading the original file to obtain the values of 'fileformat',
-   * 'fileencoding', etc.  Ignore errors.  The text itself is not used.
-   * When the file is encrypted the user is asked to enter the key.
-   */
-  if (curbuf->b_ffname != NULL)
-    orig_file_status = readfile(curbuf->b_ffname, NULL, (linenr_T)0,
-        (linenr_T)0, (linenr_T)MAXLNUM, NULL, READ_NEW);
-
-  if (b0_cm >= 0) {
-    /* Need to ask the user for the crypt key.  If this fails we continue
-     * without a key, will probably get garbage text. */
-    if (*curbuf->b_p_key != NUL) {
-      smsg((char_u *)_("Swap file is encrypted: \"%s\""), fname_used);
-      MSG_PUTS(_(
-              "\nIf you entered a new crypt key but did not write the text file,"));
-      MSG_PUTS(_("\nenter the new crypt key."));
-      MSG_PUTS(_(
-              "\nIf you wrote the text file after changing the crypt key press enter"));
-      MSG_PUTS(_("\nto use the same key for text file and swap file"));
-    } else
-      smsg((char_u *)_(need_key_msg), fname_used);
-    buf->b_p_key = get_crypt_key(FALSE, FALSE);
-    if (buf->b_p_key == NULL)
-      buf->b_p_key = curbuf->b_p_key;
-    else if (*buf->b_p_key == NUL) {
-      free(buf->b_p_key);
-      buf->b_p_key = curbuf->b_p_key;
-    }
-    if (buf->b_p_key == NULL)
-      buf->b_p_key = empty_option;
-  }
-
-  /* Use the 'fileformat' and 'fileencoding' as stored in the swap file. */
-  if (b0_ff != 0)
-    set_fileformat(b0_ff - 1, OPT_LOCAL);
-  if (b0_fenc != NULL) {
-    set_option_value((char_u *)"fenc", 0L, b0_fenc, OPT_LOCAL);
-    free(b0_fenc);
-  }
-  unchanged(curbuf, TRUE);
-
-  bnum = 1;             /* start with block 1 */
-  page_count = 1;       /* which is 1 page */
-  lnum = 0;             /* append after line 0 in curbuf */
-  line_count = 0;
-  idx = 0;              /* start with first index in block 1 */
-  error = 0;
-  buf->b_ml.ml_stack_top = 0;
-  buf->b_ml.ml_stack = NULL;
-  buf->b_ml.ml_stack_size = 0;          /* no stack yet */
-
-  if (curbuf->b_ffname == NULL)
-    cannot_open = TRUE;
-  else
-    cannot_open = FALSE;
-
-  serious_error = FALSE;
-  for (; !got_int; line_breakcheck()) {
-    if (hp != NULL)
-      mf_put(mfp, hp, FALSE, FALSE);            /* release previous block */
-
-    /*
-     * get block
-     */
-    if ((hp = mf_get(mfp, (blocknr_T)bnum, page_count)) == NULL) {
-      if (bnum == 1) {
-        EMSG2(_("E309: Unable to read block 1 from %s"), mfp->mf_fname);
-        goto theend;
-      }
-      ++error;
-      ml_append(lnum++, (char_u *)_("???MANY LINES MISSING"),
-          (colnr_T)0, TRUE);
-    } else {          /* there is a block */
-      pp = (PTR_BL *)(hp->bh_data);
-      if (pp->pb_id == PTR_ID) {                /* it is a pointer block */
-        /* check line count when using pointer block first time */
-        if (idx == 0 && line_count != 0) {
-          for (i = 0; i < (int)pp->pb_count; ++i)
-            line_count -= pp->pb_pointer[i].pe_line_count;
-          if (line_count != 0) {
-            ++error;
-            ml_append(lnum++, (char_u *)_("???LINE COUNT WRONG"),
-                (colnr_T)0, TRUE);
-          }
-        }
-
-        if (pp->pb_count == 0) {
-          ml_append(lnum++, (char_u *)_("???EMPTY BLOCK"),
-              (colnr_T)0, TRUE);
-          ++error;
-        } else if (idx < (int)pp->pb_count) {         /* go a block deeper */
-          if (pp->pb_pointer[idx].pe_bnum < 0) {
-            /*
-             * Data block with negative block number.
-             * Try to read lines from the original file.
-             * This is slow, but it works.
-             */
-            if (!cannot_open) {
-              line_count = pp->pb_pointer[idx].pe_line_count;
-              if (readfile(curbuf->b_ffname, NULL, lnum,
-                      pp->pb_pointer[idx].pe_old_lnum - 1,
-                      line_count, NULL, 0) == FAIL)
-                cannot_open = TRUE;
-              else
-                lnum += line_count;
-            }
-            if (cannot_open) {
-              ++error;
-              ml_append(lnum++, (char_u *)_("???LINES MISSING"),
-                  (colnr_T)0, TRUE);
-            }
-            ++idx;                  /* get same block again for next index */
-            continue;
-          }
-
-          /*
-           * going one block deeper in the tree
-           */
-          top = ml_add_stack(buf);  // new entry in stack
-          ip = &(buf->b_ml.ml_stack[top]);
-          ip->ip_bnum = bnum;
-          ip->ip_index = idx;
-
-          bnum = pp->pb_pointer[idx].pe_bnum;
-          line_count = pp->pb_pointer[idx].pe_line_count;
-          page_count = pp->pb_pointer[idx].pe_page_count;
-          idx = 0;
-          continue;
-        }
-      } else {            /* not a pointer block */
-        dp = (DATA_BL *)(hp->bh_data);
-        if (dp->db_id != DATA_ID) {             /* block id wrong */
-          if (bnum == 1) {
-            EMSG2(_("E310: Block 1 ID wrong (%s not a .swp file?)"),
-                mfp->mf_fname);
-            goto theend;
-          }
-          ++error;
-          ml_append(lnum++, (char_u *)_("???BLOCK MISSING"),
-              (colnr_T)0, TRUE);
-        } else {
-          /*
-           * it is a data block
-           * Append all the lines in this block
-           */
-          has_error = FALSE;
-          /*
-           * check length of block
-           * if wrong, use length in pointer block
-           */
-          if (page_count * mfp->mf_page_size != dp->db_txt_end) {
-            ml_append(lnum++,
-                (char_u *)_("??? from here until ???END lines may be messed up"),
-                (colnr_T)0, TRUE);
-            ++error;
-            has_error = TRUE;
-            dp->db_txt_end = page_count * mfp->mf_page_size;
-          }
-
-          /* make sure there is a NUL at the end of the block */
-          *((char_u *)dp + dp->db_txt_end - 1) = NUL;
-
-          /*
-           * check number of lines in block
-           * if wrong, use count in data block
-           */
-          if (line_count != dp->db_line_count) {
-            ml_append(lnum++,
-                (char_u *)_(
-                    "??? from here until ???END lines may have been inserted/deleted"),
-                (colnr_T)0, TRUE);
-            ++error;
-            has_error = TRUE;
-          }
-
-          for (i = 0; i < dp->db_line_count; ++i) {
-            txt_start = (dp->db_index[i] & DB_INDEX_MASK);
-            if (txt_start <= (int)HEADER_SIZE
-                || txt_start >= (int)dp->db_txt_end) {
-              p = (char_u *)"???";
-              ++error;
-            } else
-              p = (char_u *)dp + txt_start;
-            ml_append(lnum++, p, (colnr_T)0, TRUE);
-          }
-          if (has_error)
-            ml_append(lnum++, (char_u *)_("???END"),
-                (colnr_T)0, TRUE);
-        }
-      }
-    }
-
-    if (buf->b_ml.ml_stack_top == 0)            /* finished */
-      break;
-
-    /*
-     * go one block up in the tree
-     */
-    ip = &(buf->b_ml.ml_stack[--(buf->b_ml.ml_stack_top)]);
-    bnum = ip->ip_bnum;
-    idx = ip->ip_index + 1;         /* go to next index */
-    page_count = 1;
-  }
-
-  /*
-   * Compare the buffer contents with the original file.  When they differ
-   * set the 'modified' flag.
-   * Lines 1 - lnum are the new contents.
-   * Lines lnum + 1 to ml_line_count are the original contents.
-   * Line ml_line_count + 1 in the dummy empty line.
-   */
-  if (orig_file_status != OK || curbuf->b_ml.ml_line_count != lnum * 2 + 1) {
-    /* Recovering an empty file results in two lines and the first line is
-     * empty.  Don't set the modified flag then. */
-    if (!(curbuf->b_ml.ml_line_count == 2 && *ml_get(1) == NUL)) {
-      changed_int();
-      ++curbuf->b_changedtick;
-    }
-  } else {
-    for (idx = 1; idx <= lnum; ++idx) {
-      /* Need to copy one line, fetching the other one may flush it. */
-      p = vim_strsave(ml_get(idx));
-      i = STRCMP(p, ml_get(idx + lnum));
-      free(p);
-      if (i != 0) {
-        changed_int();
-        ++curbuf->b_changedtick;
-        break;
-      }
-    }
-  }
-
-  /*
-   * Delete the lines from the original file and the dummy line from the
-   * empty buffer.  These will now be after the last line in the buffer.
-   */
-  while (curbuf->b_ml.ml_line_count > lnum
-         && !(curbuf->b_ml.ml_flags & ML_EMPTY))
-    ml_delete(curbuf->b_ml.ml_line_count, FALSE);
-  curbuf->b_flags |= BF_RECOVERED;
-
-  recoverymode = FALSE;
-  if (got_int)
-    EMSG(_("E311: Recovery Interrupted"));
-  else if (error) {
-    ++no_wait_return;
-    MSG(">>>>>>>>>>>>>");
-    EMSG(_(
-            "E312: Errors detected while recovering; look for lines starting with ???"));
-    --no_wait_return;
-    MSG(_("See \":help E312\" for more information."));
-    MSG(">>>>>>>>>>>>>");
-  } else {
-    if (curbuf->b_changed) {
-      MSG(_("Recovery completed. You should check if everything is OK."));
-      MSG_PUTS(_(
-              "\n(You might want to write out this file under another name\n"));
-      MSG_PUTS(_("and run diff with the original file to check for changes)"));
-    } else
-      MSG(_("Recovery completed. Buffer contents equals file contents."));
-    MSG_PUTS(_("\nYou may want to delete the .swp file now.\n\n"));
-    cmdline_row = msg_row;
-  }
-  if (*buf->b_p_key != NUL && STRCMP(curbuf->b_p_key, buf->b_p_key) != 0) {
-    MSG_PUTS(_("Using crypt key from swap file for the text file.\n"));
-    set_option_value((char_u *)"key", 0L, buf->b_p_key, OPT_LOCAL);
-  }
-  redraw_curbuf_later(NOT_VALID);
-
-theend:
-  free(fname_used);
-  recoverymode = FALSE;
-  if (mfp != NULL) {
-    if (hp != NULL)
-      mf_put(mfp, hp, FALSE, FALSE);
-    mf_close(mfp, FALSE);           /* will also free(mfp->mf_fname) */
-  }
-  if (buf != NULL) {
-    if (buf->b_p_key != curbuf->b_p_key)
-      free_string_option(buf->b_p_key);
-    free_string_option(buf->b_p_cm);
-    free(buf->b_ml.ml_stack);
-    free(buf);
-  }
-  if (serious_error && called_from_main)
-    ml_close(curbuf, TRUE);
-  else {
-    apply_autocmds(EVENT_BUFREADPOST, NULL, curbuf->b_fname, FALSE, curbuf);
-    apply_autocmds(EVENT_BUFWINENTER, NULL, curbuf->b_fname, FALSE, curbuf);
-  }
-  return;
-}
-
-/*
- * Find the names of swap files in current directory and the directory given
- * with the 'directory' option.
- *
- * Used to:
- * - list the swap files for "vim -r"
- * - count the number of swap files when recovering
- * - list the swap files when recovering
- * - find the name of the n'th swap file when recovering
- */
-int 
-recover_names (
-    char_u *fname,             /* base for swap file name */
-    int list,                       /* when TRUE, list the swap file names */
-    int nr,                         /* when non-zero, return nr'th swap file name */
-    char_u **fname_out        /* result when "nr" > 0 */
-)
-{
-  int num_names;
-  char_u      *(names[6]);
-  char_u      *tail;
-  char_u      *p;
-  int num_files;
-  int file_count = 0;
-  char_u      **files;
-  int i;
-  char_u      *dirp;
-  char_u      *dir_name;
-  char_u      *fname_res = NULL;
-#ifdef HAVE_READLINK
-  char_u fname_buf[MAXPATHL];
-#endif
-
-  if (fname != NULL) {
-#ifdef HAVE_READLINK
-    /* Expand symlink in the file name, because the swap file is created
-     * with the actual file instead of with the symlink. */
-    if (resolve_symlink(fname, fname_buf) == OK)
-      fname_res = fname_buf;
-    else
-#endif
-    fname_res = fname;
-  }
-
-  if (list) {
-    /* use msg() to start the scrolling properly */
-    msg((char_u *)_("Swap files found:"));
-    msg_putchar('\n');
-  }
-
-  /*
-   * Do the loop for every directory in 'directory'.
-   * First allocate some memory to put the directory name in.
-   */
-  dir_name = alloc((unsigned)STRLEN(p_dir) + 1);
-  dirp = p_dir;
-  while (dir_name != NULL && *dirp) {
-    /*
-     * Isolate a directory name from *dirp and put it in dir_name (we know
-     * it is large enough, so use 31000 for length).
-     * Advance dirp to next directory name.
-     */
-    (void)copy_option_part(&dirp, dir_name, 31000, ",");
-
-    if (dir_name[0] == '.' && dir_name[1] == NUL) {     /* check current dir */
-      if (fname == NULL) {
-        names[0] = vim_strsave((char_u *)"*.sw?");
-#if defined(UNIX) || defined(WIN3264)
-        /* For Unix names starting with a dot are special.  MS-Windows
-         * supports this too, on some file systems. */
-        names[1] = vim_strsave((char_u *)".*.sw?");
-        names[2] = vim_strsave((char_u *)".sw?");
-        num_names = 3;
-#else
-        num_names = 1;
-#endif
-      } else
-        num_names = recov_file_names(names, fname_res, TRUE);
-    } else {                      /* check directory dir_name */
-      if (fname == NULL) {
-        names[0] = concat_fnames(dir_name, (char_u *)"*.sw?", TRUE);
-#if defined(UNIX) || defined(WIN3264)
-        /* For Unix names starting with a dot are special.  MS-Windows
-         * supports this too, on some file systems. */
-        names[1] = concat_fnames(dir_name, (char_u *)".*.sw?", TRUE);
-        names[2] = concat_fnames(dir_name, (char_u *)".sw?", TRUE);
-        num_names = 3;
-#else
-        num_names = 1;
-#endif
-      } else {
-#if defined(UNIX) || defined(WIN3264)
-        p = dir_name + STRLEN(dir_name);
-        if (after_pathsep(dir_name, p) && p[-1] == p[-2]) {
-          /* Ends with '//', Use Full path for swap name */
-          tail = make_percent_swname(dir_name, fname_res);
-        } else
-#endif
-        tail = path_tail(fname_res);
-        tail = concat_fnames(dir_name, tail, TRUE);
-        num_names = recov_file_names(names, tail, FALSE);
-        free(tail);
-      }
-    }
-
-    /* check for out-of-memory */
-    for (i = 0; i < num_names; ++i) {
-      if (names[i] == NULL) {
-        for (i = 0; i < num_names; ++i)
-          free(names[i]);
-        num_names = 0;
-      }
-    }
-    if (num_names == 0)
-      num_files = 0;
-    else if (expand_wildcards(num_names, names, &num_files, &files,
-                 EW_KEEPALL|EW_FILE|EW_SILENT) == FAIL)
-      num_files = 0;
-
-    /*
-     * When no swap file found, wildcard expansion might have failed (e.g.
-     * not able to execute the shell).
-     * Try finding a swap file by simply adding ".swp" to the file name.
-     */
-    if (*dirp == NUL && file_count + num_files == 0 && fname != NULL) {
-      char_u *swapname = modname(fname_res, (char_u *)".swp", TRUE);
-      if (swapname != NULL) {
-        if (os_file_exists(swapname)) {
-          files = (char_u **)alloc((unsigned)sizeof(char_u *));
-          files[0] = swapname;
-          swapname = NULL;
-          num_files = 1;
-        }
-        free(swapname);
-      }
-    }
-
-    /*
-     * remove swapfile name of the current buffer, it must be ignored
-     */
-    if (curbuf->b_ml.ml_mfp != NULL
-        && (p = curbuf->b_ml.ml_mfp->mf_fname) != NULL) {
-      for (i = 0; i < num_files; ++i)
-        if (path_full_compare(p, files[i], TRUE) & kEqualFiles) {
-          /* Remove the name from files[i].  Move further entries
-           * down.  When the array becomes empty free it here, since
-           * FreeWild() won't be called below. */
-          free(files[i]);
-          if (--num_files == 0)
-            free(files);
-          else
-            for (; i < num_files; ++i)
-              files[i] = files[i + 1];
-        }
-    }
-    if (nr > 0) {
-      file_count += num_files;
-      if (nr <= file_count) {
-        *fname_out = vim_strsave(
-            files[nr - 1 + num_files - file_count]);
-        dirp = (char_u *)"";                        /* stop searching */
-      }
-    } else if (list) {
-      if (dir_name[0] == '.' && dir_name[1] == NUL) {
-        if (fname == NULL)
-          MSG_PUTS(_("   In current directory:\n"));
-        else
-          MSG_PUTS(_("   Using specified name:\n"));
-      } else {
-        MSG_PUTS(_("   In directory "));
-        msg_home_replace(dir_name);
-        MSG_PUTS(":\n");
-      }
-
-      if (num_files) {
-        for (i = 0; i < num_files; ++i) {
-          /* print the swap file name */
-          msg_outnum((long)++file_count);
-          MSG_PUTS(".    ");
-          msg_puts(path_tail(files[i]));
-          msg_putchar('\n');
-          (void)swapfile_info(files[i]);
-        }
-      } else
-        MSG_PUTS(_("      -- none --\n"));
-      out_flush();
-    } else
-      file_count += num_files;
-
-    for (i = 0; i < num_names; ++i)
-      free(names[i]);
-    if (num_files > 0)
-      FreeWild(num_files, files);
-  }
-  free(dir_name);
-  return file_count;
-}
-
-#if defined(UNIX) || defined(WIN3264)  /* Need _very_ long file names */
-/*
- * Append the full path to name with path separators made into percent
- * signs, to dir. An unnamed buffer is handled as "" (<currentdir>/"")
- */
-static char_u *make_percent_swname(char_u *dir, char_u *name)
-{
-  char_u *d, *s, *f;
-
-  f = fix_fname(name != NULL ? name : (char_u *) "");
-  d = NULL;
-  if (f != NULL) {
-    s = (char_u *)xstrdup((char *)f);
-    for (d = s; *d != NUL; mb_ptr_adv(d))
-      if (vim_ispathsep(*d))
-        *d = '%';
-    d = concat_fnames(dir, s, TRUE);
-    free(s);
-    free(f);
-  }
-  return d;
-}
-#endif
-
-#if defined(UNIX) && (defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG))
-static int process_still_running;
-#endif
-
-/*
- * Give information about an existing swap file.
- * Returns timestamp (0 when unknown).
- */
-static time_t swapfile_info(char_u *fname)
-{
-  int fd;
-  struct block0 b0;
-  time_t x = (time_t)0;
-  char            *p;
-#ifdef UNIX
-  char uname[B0_UNAME_SIZE];
-#endif
-
-  /* print the swap file date */
-  FileInfo file_info;
-  if (os_get_file_info((char *)fname, &file_info)) {
-#ifdef UNIX
-    /* print name of owner of the file */
-    if (os_get_uname(file_info.stat.st_uid, uname, B0_UNAME_SIZE) == OK) {
-      MSG_PUTS(_("          owned by: "));
-      msg_outtrans((char_u *)uname);
-      MSG_PUTS(_("   dated: "));
-    } else
-#endif
-    MSG_PUTS(_("             dated: "));
-    x = file_info.stat.st_mtim.tv_sec;
-    p = ctime(&x);  // includes '\n'
-    if (p == NULL)
-      MSG_PUTS("(invalid)\n");
-    else
-      MSG_PUTS(p);
-  }
-
-  /*
-   * print the original file name
-   */
-  fd = mch_open((char *)fname, O_RDONLY, 0);
-  if (fd >= 0) {
-    if (read_eintr(fd, &b0, sizeof(b0)) == sizeof(b0)) {
-      if (STRNCMP(b0.b0_version, "VIM 3.0", 7) == 0) {
-        MSG_PUTS(_("         [from Vim version 3.0]"));
-      } else if (ml_check_b0_id(&b0) == FAIL) {
-        MSG_PUTS(_("         [does not look like a Vim swap file]"));
-      } else {
-        MSG_PUTS(_("         file name: "));
-        if (b0.b0_fname[0] == NUL)
-          MSG_PUTS(_("[No Name]"));
-        else
-          msg_outtrans(b0.b0_fname);
-
-        MSG_PUTS(_("\n          modified: "));
-        MSG_PUTS(b0.b0_dirty ? _("YES") : _("no"));
-
-        if (*(b0.b0_uname) != NUL) {
-          MSG_PUTS(_("\n         user name: "));
-          msg_outtrans(b0.b0_uname);
-        }
-
-        if (*(b0.b0_hname) != NUL) {
-          if (*(b0.b0_uname) != NUL)
-            MSG_PUTS(_("   host name: "));
-          else
-            MSG_PUTS(_("\n         host name: "));
-          msg_outtrans(b0.b0_hname);
-        }
-
-        if (char_to_long(b0.b0_pid) != 0L) {
-          MSG_PUTS(_("\n        process ID: "));
-          msg_outnum(char_to_long(b0.b0_pid));
-#if defined(UNIX)
-          if (kill((pid_t)char_to_long(b0.b0_pid), 0) == 0) {
-            MSG_PUTS(_(" (still running)"));
-            process_still_running = TRUE;
-          }
-#endif
-        }
-
-        if (b0_magic_wrong(&b0)) {
-          MSG_PUTS(_("\n         [not usable on this computer]"));
-        }
-      }
-    } else
-      MSG_PUTS(_("         [cannot be read]"));
-    close(fd);
-  } else
-    MSG_PUTS(_("         [cannot be opened]"));
-  msg_putchar('\n');
-
-  return x;
-}
-
-static int recov_file_names(char_u **names, char_u *path, int prepend_dot)
-{
-  int num_names;
-  char_u      *p;
-  int i;
-
-  num_names = 0;
-
-  /*
-   * May also add the file name with a dot prepended, for swap file in same
-   * dir as original file.
-   */
-  if (prepend_dot) {
-    names[num_names] = modname(path, (char_u *)".sw?", TRUE);
-    if (names[num_names] == NULL)
-      return num_names;
-    ++num_names;
-  }
-
-  // Form the normal swap file name pattern by appending ".sw?".
-  names[num_names] = concat_fnames(path, (char_u *)".sw?", FALSE);
-  if (num_names >= 1) {     /* check if we have the same name twice */
-    p = names[num_names - 1];
-    i = (int)STRLEN(names[num_names - 1]) - (int)STRLEN(names[num_names]);
-    if (i > 0)
-      p += i;               /* file name has been expanded to full path */
-
-    if (STRCMP(p, names[num_names]) != 0)
-      ++num_names;
-    else
-      free(names[num_names]);
-  } else
-    ++num_names;
-
-  return num_names;
-}
-
-/*
- * sync all memlines
- *
- * If 'check_file' is TRUE, check if original file exists and was not changed.
- * If 'check_char' is TRUE, stop syncing when character becomes available, but
- * always sync at least one block.
- */
-void ml_sync_all(int check_file, int check_char)
-{
-  buf_T               *buf;
-
-  for (buf = firstbuf; buf != NULL; buf = buf->b_next) {
-    if (buf->b_ml.ml_mfp == NULL || buf->b_ml.ml_mfp->mf_fname == NULL)
-      continue;                             /* no file */
-
-    ml_flush_line(buf);                     /* flush buffered line */
-                                            /* flush locked block */
-    (void)ml_find_line(buf, (linenr_T)0, ML_FLUSH);
-    if (bufIsChanged(buf) && check_file && mf_need_trans(buf->b_ml.ml_mfp)
-        && buf->b_ffname != NULL) {
-      /*
-       * If the original file does not exist anymore or has been changed
-       * call ml_preserve() to get rid of all negative numbered blocks.
-       */
-      FileInfo file_info;
-      if (!os_get_file_info((char *)buf->b_ffname, &file_info)
-          || file_info.stat.st_mtim.tv_sec != buf->b_mtime_read
-          || (off_t)file_info.stat.st_size != buf->b_orig_size) {
-        ml_preserve(buf, FALSE);
-        did_check_timestamps = FALSE;
-        need_check_timestamps = TRUE;           /* give message later */
-      }
-    }
-    if (buf->b_ml.ml_mfp->mf_dirty) {
-      (void)mf_sync(buf->b_ml.ml_mfp, (check_char ? MFS_STOP : 0)
-          | (bufIsChanged(buf) ? MFS_FLUSH : 0));
-      if (check_char && ui_char_avail())        /* character available now */
-        break;
-    }
-  }
-}
-
-/*
- * sync one buffer, including negative blocks
- *
- * after this all the blocks are in the swap file
- *
- * Used for the :preserve command and when the original file has been
- * changed or deleted.
- *
- * when message is TRUE the success of preserving is reported
- */
-void ml_preserve(buf_T *buf, int message)
-{
-  bhdr_T      *hp;
-  linenr_T lnum;
-  memfile_T   *mfp = buf->b_ml.ml_mfp;
-  int status;
-  int got_int_save = got_int;
-
-  if (mfp == NULL || mfp->mf_fname == NULL) {
-    if (message)
-      EMSG(_("E313: Cannot preserve, there is no swap file"));
-    return;
-  }
-
-  /* We only want to stop when interrupted here, not when interrupted
-   * before. */
-  got_int = FALSE;
-
-  ml_flush_line(buf);                               /* flush buffered line */
-  (void)ml_find_line(buf, (linenr_T)0, ML_FLUSH);   /* flush locked block */
-  status = mf_sync(mfp, MFS_ALL | MFS_FLUSH);
-
-  /* stack is invalid after mf_sync(.., MFS_ALL) */
-  buf->b_ml.ml_stack_top = 0;
-
-  /*
-   * Some of the data blocks may have been changed from negative to
-   * positive block number. In that case the pointer blocks need to be
-   * updated.
-   *
-   * We don't know in which pointer block the references are, so we visit
-   * all data blocks until there are no more translations to be done (or
-   * we hit the end of the file, which can only happen in case a write fails,
-   * e.g. when file system if full).
-   * ml_find_line() does the work by translating the negative block numbers
-   * when getting the first line of each data block.
-   */
-  if (mf_need_trans(mfp) && !got_int) {
-    lnum = 1;
-    while (mf_need_trans(mfp) && lnum <= buf->b_ml.ml_line_count) {
-      hp = ml_find_line(buf, lnum, ML_FIND);
-      if (hp == NULL) {
-        status = FAIL;
-        goto theend;
-      }
-      CHECK(buf->b_ml.ml_locked_low != lnum, "low != lnum");
-      lnum = buf->b_ml.ml_locked_high + 1;
-    }
-    (void)ml_find_line(buf, (linenr_T)0, ML_FLUSH);     /* flush locked block */
-    /* sync the updated pointer blocks */
-    if (mf_sync(mfp, MFS_ALL | MFS_FLUSH) == FAIL)
-      status = FAIL;
-    buf->b_ml.ml_stack_top = 0;             /* stack is invalid now */
-  }
-theend:
-  got_int |= got_int_save;
-
-  if (message) {
-    if (status == OK)
-      MSG(_("File preserved"));
-    else
-      EMSG(_("E314: Preserve failed"));
-  }
-}
-
-/*
- * NOTE: The pointer returned by the ml_get_*() functions only remains valid
- * until the next call!
- *  line1 = ml_get(1);
- *  line2 = ml_get(2);	// line1 is now invalid!
- * Make a copy of the line if necessary.
- */
-/*
- * Return a pointer to a (read-only copy of a) line.
- *
- * On failure an error message is given and IObuff is returned (to avoid
- * having to check for error everywhere).
- */
-char_u *ml_get(linenr_T lnum)
-{
-  return ml_get_buf(curbuf, lnum, FALSE);
-}
-
-/*
- * Return pointer to position "pos".
- */
-char_u *ml_get_pos(pos_T *pos)
-{
-  return ml_get_buf(curbuf, pos->lnum, FALSE) + pos->col;
-}
-
-/*
- * Return pointer to cursor line.
- */
-char_u *ml_get_curline(void)
-{
-  return ml_get_buf(curbuf, curwin->w_cursor.lnum, FALSE);
-}
-
-/*
- * Return pointer to cursor position.
- */
-char_u *ml_get_cursor(void)
-{
-  return ml_get_buf(curbuf, curwin->w_cursor.lnum, FALSE) +
-         curwin->w_cursor.col;
-}
-
-/*
- * Return a pointer to a line in a specific buffer
- *
- * "will_change": if TRUE mark the buffer dirty (chars in the line will be
- * changed)
- */
-char_u *
-ml_get_buf (
-    buf_T *buf,
-    linenr_T lnum,
-    int will_change                        /* line will be changed */
-)
-{
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-  char_u      *ptr;
-  static int recursive = 0;
-
-  if (lnum > buf->b_ml.ml_line_count) { /* invalid line number */
-    if (recursive == 0) {
-      /* Avoid giving this message for a recursive call, may happen when
-       * the GUI redraws part of the text. */
-      ++recursive;
-      EMSGN(_("E315: ml_get: invalid lnum: %" PRId64), lnum);
-      --recursive;
-    }
-errorret:
-    STRCPY(IObuff, "???");
-    return IObuff;
-  }
-  if (lnum <= 0)                        /* pretend line 0 is line 1 */
-    lnum = 1;
-
-  if (buf->b_ml.ml_mfp == NULL)         /* there are no lines */
-    return (char_u *)"";
-
-  /*
-   * See if it is the same line as requested last time.
-   * Otherwise may need to flush last used line.
-   * Don't use the last used line when 'swapfile' is reset, need to load all
-   * blocks.
-   */
-  if (buf->b_ml.ml_line_lnum != lnum || mf_dont_release) {
-    ml_flush_line(buf);
-
-    /*
-     * Find the data block containing the line.
-     * This also fills the stack with the blocks from the root to the data
-     * block and releases any locked block.
-     */
-    if ((hp = ml_find_line(buf, lnum, ML_FIND)) == NULL) {
-      if (recursive == 0) {
-        /* Avoid giving this message for a recursive call, may happen
-         * when the GUI redraws part of the text. */
-        ++recursive;
-        EMSGN(_("E316: ml_get: cannot find line %" PRId64), lnum);
-        --recursive;
-      }
-      goto errorret;
-    }
-
-    dp = (DATA_BL *)(hp->bh_data);
-
-    ptr = (char_u *)dp +
-          ((dp->db_index[lnum - buf->b_ml.ml_locked_low]) & DB_INDEX_MASK);
-    buf->b_ml.ml_line_ptr = ptr;
-    buf->b_ml.ml_line_lnum = lnum;
-    buf->b_ml.ml_flags &= ~ML_LINE_DIRTY;
-  }
-  if (will_change)
-    buf->b_ml.ml_flags |= (ML_LOCKED_DIRTY | ML_LOCKED_POS);
-
-  return buf->b_ml.ml_line_ptr;
-}
-
-/*
- * Check if a line that was just obtained by a call to ml_get
- * is in allocated memory.
- */
-int ml_line_alloced(void)
-{
-  return curbuf->b_ml.ml_flags & ML_LINE_DIRTY;
-}
-
-/*
- * Append a line after lnum (may be 0 to insert a line in front of the file).
- * "line" does not need to be allocated, but can't be another line in a
- * buffer, unlocking may make it invalid.
- *
- *   newfile: TRUE when starting to edit a new file, meaning that pe_old_lnum
- *		will be set for recovery
- * Check: The caller of this function should probably also call
- * appended_lines().
- *
- * return FAIL for failure, OK otherwise
- */
-int 
-ml_append (
-    linenr_T lnum,                  /* append after this line (can be 0) */
-    char_u *line,              /* text of the new line */
-    colnr_T len,                    /* length of new line, including NUL, or 0 */
-    int newfile                    /* flag, see above */
-)
-{
-  /* When starting up, we might still need to create the memfile */
-  if (curbuf->b_ml.ml_mfp == NULL && open_buffer(FALSE, NULL, 0) == FAIL)
-    return FAIL;
-
-  if (curbuf->b_ml.ml_line_lnum != 0)
-    ml_flush_line(curbuf);
-  return ml_append_int(curbuf, lnum, line, len, newfile, FALSE);
-}
-
-/*
- * Like ml_append() but for an arbitrary buffer.  The buffer must already have
- * a memline.
- */
-int 
-ml_append_buf (
-    buf_T *buf,
-    linenr_T lnum,                  /* append after this line (can be 0) */
-    char_u *line,              /* text of the new line */
-    colnr_T len,                    /* length of new line, including NUL, or 0 */
-    int newfile                    /* flag, see above */
-)
-{
-  if (buf->b_ml.ml_mfp == NULL)
-    return FAIL;
-
-  if (buf->b_ml.ml_line_lnum != 0)
-    ml_flush_line(buf);
-  return ml_append_int(buf, lnum, line, len, newfile, FALSE);
-}
-
-static int 
-ml_append_int (
-    buf_T *buf,
-    linenr_T lnum,                  /* append after this line (can be 0) */
-    char_u *line,              /* text of the new line */
-    colnr_T len,                    /* length of line, including NUL, or 0 */
-    int newfile,                    /* flag, see above */
-    int mark                       /* mark the new line */
-)
-{
-  int i;
-  int line_count;               /* number of indexes in current block */
-  int offset;
-  int from, to;
-  int space_needed;             /* space needed for new line */
-  int page_size;
-  int page_count;
-  int db_idx;                   /* index for lnum in data block */
-  bhdr_T      *hp;
-  memfile_T   *mfp;
-  DATA_BL     *dp;
-  PTR_BL      *pp;
-  infoptr_T   *ip;
-
-  /* lnum out of range */
-  if (lnum > buf->b_ml.ml_line_count || buf->b_ml.ml_mfp == NULL)
-    return FAIL;
-
-  if (lowest_marked && lowest_marked > lnum)
-    lowest_marked = lnum + 1;
-
-  if (len == 0)
-    len = (colnr_T)STRLEN(line) + 1;            /* space needed for the text */
-  space_needed = len + INDEX_SIZE;      /* space needed for text + index */
-
-  mfp = buf->b_ml.ml_mfp;
-  page_size = mfp->mf_page_size;
-
-  /*
-   * find the data block containing the previous line
-   * This also fills the stack with the blocks from the root to the data block
-   * This also releases any locked block.
-   */
-  if ((hp = ml_find_line(buf, lnum == 0 ? (linenr_T)1 : lnum,
-           ML_INSERT)) == NULL)
-    return FAIL;
-
-  buf->b_ml.ml_flags &= ~ML_EMPTY;
-
-  if (lnum == 0)                /* got line one instead, correct db_idx */
-    db_idx = -1;                /* careful, it is negative! */
-  else
-    db_idx = lnum - buf->b_ml.ml_locked_low;
-  /* get line count before the insertion */
-  line_count = buf->b_ml.ml_locked_high - buf->b_ml.ml_locked_low;
-
-  dp = (DATA_BL *)(hp->bh_data);
-
-  /*
-   * If
-   * - there is not enough room in the current block
-   * - appending to the last line in the block
-   * - not appending to the last line in the file
-   * insert in front of the next block.
-   */
-  if ((int)dp->db_free < space_needed && db_idx == line_count - 1
-      && lnum < buf->b_ml.ml_line_count) {
-    /*
-     * Now that the line is not going to be inserted in the block that we
-     * expected, the line count has to be adjusted in the pointer blocks
-     * by using ml_locked_lineadd.
-     */
-    --(buf->b_ml.ml_locked_lineadd);
-    --(buf->b_ml.ml_locked_high);
-    if ((hp = ml_find_line(buf, lnum + 1, ML_INSERT)) == NULL)
-      return FAIL;
-
-    db_idx = -1;                    /* careful, it is negative! */
-    /* get line count before the insertion */
-    line_count = buf->b_ml.ml_locked_high - buf->b_ml.ml_locked_low;
-    CHECK(buf->b_ml.ml_locked_low != lnum + 1, "locked_low != lnum + 1");
-
-    dp = (DATA_BL *)(hp->bh_data);
-  }
-
-  ++buf->b_ml.ml_line_count;
-
-  if ((int)dp->db_free >= space_needed) {       /* enough room in data block */
-    /*
-     * Insert new line in existing data block, or in data block allocated above.
-     */
-    dp->db_txt_start -= len;
-    dp->db_free -= space_needed;
-    ++(dp->db_line_count);
-
-    /*
-     * move the text of the lines that follow to the front
-     * adjust the indexes of the lines that follow
-     */
-    if (line_count > db_idx + 1) {          /* if there are following lines */
-      /*
-       * Offset is the start of the previous line.
-       * This will become the character just after the new line.
-       */
-      if (db_idx < 0)
-        offset = dp->db_txt_end;
-      else
-        offset = ((dp->db_index[db_idx]) & DB_INDEX_MASK);
-      memmove((char *)dp + dp->db_txt_start,
-          (char *)dp + dp->db_txt_start + len,
-          (size_t)(offset - (dp->db_txt_start + len)));
-      for (i = line_count - 1; i > db_idx; --i)
-        dp->db_index[i + 1] = dp->db_index[i] - len;
-      dp->db_index[db_idx + 1] = offset - len;
-    } else                                  /* add line at the end */
-      dp->db_index[db_idx + 1] = dp->db_txt_start;
-
-    /*
-     * copy the text into the block
-     */
-    memmove((char *)dp + dp->db_index[db_idx + 1], line, (size_t)len);
-    if (mark)
-      dp->db_index[db_idx + 1] |= DB_MARKED;
-
-    /*
-     * Mark the block dirty.
-     */
-    buf->b_ml.ml_flags |= ML_LOCKED_DIRTY;
-    if (!newfile)
-      buf->b_ml.ml_flags |= ML_LOCKED_POS;
-  } else {        /* not enough space in data block */
-    /*
-     * If there is not enough room we have to create a new data block and copy some
-     * lines into it.
-     * Then we have to insert an entry in the pointer block.
-     * If this pointer block also is full, we go up another block, and so on, up
-     * to the root if necessary.
-     * The line counts in the pointer blocks have already been adjusted by
-     * ml_find_line().
-     */
-    long line_count_left, line_count_right;
-    int page_count_left, page_count_right;
-    bhdr_T      *hp_left;
-    bhdr_T      *hp_right;
-    bhdr_T      *hp_new;
-    int lines_moved;
-    int data_moved = 0;                     /* init to shut up gcc */
-    int total_moved = 0;                    /* init to shut up gcc */
-    DATA_BL     *dp_right, *dp_left;
-    int stack_idx;
-    int in_left;
-    int lineadd;
-    blocknr_T bnum_left, bnum_right;
-    linenr_T lnum_left, lnum_right;
-    int pb_idx;
-    PTR_BL      *pp_new;
-
-    /*
-     * We are going to allocate a new data block. Depending on the
-     * situation it will be put to the left or right of the existing
-     * block.  If possible we put the new line in the left block and move
-     * the lines after it to the right block. Otherwise the new line is
-     * also put in the right block. This method is more efficient when
-     * inserting a lot of lines at one place.
-     */
-    if (db_idx < 0) {           /* left block is new, right block is existing */
-      lines_moved = 0;
-      in_left = TRUE;
-      /* space_needed does not change */
-    } else {                  /* left block is existing, right block is new */
-      lines_moved = line_count - db_idx - 1;
-      if (lines_moved == 0)
-        in_left = FALSE;                /* put new line in right block */
-                                        /* space_needed does not change */
-      else {
-        data_moved = ((dp->db_index[db_idx]) & DB_INDEX_MASK) -
-                     dp->db_txt_start;
-        total_moved = data_moved + lines_moved * INDEX_SIZE;
-        if ((int)dp->db_free + total_moved >= space_needed) {
-          in_left = TRUE;               /* put new line in left block */
-          space_needed = total_moved;
-        } else {
-          in_left = FALSE;                  /* put new line in right block */
-          space_needed += total_moved;
-        }
-      }
-    }
-
-    page_count = ((space_needed + HEADER_SIZE) + page_size - 1) / page_size;
-    if ((hp_new = ml_new_data(mfp, newfile, page_count)) == NULL) {
-      /* correct line counts in pointer blocks */
-      --(buf->b_ml.ml_locked_lineadd);
-      --(buf->b_ml.ml_locked_high);
-      return FAIL;
-    }
-    if (db_idx < 0) {           /* left block is new */
-      hp_left = hp_new;
-      hp_right = hp;
-      line_count_left = 0;
-      line_count_right = line_count;
-    } else {                  /* right block is new */
-      hp_left = hp;
-      hp_right = hp_new;
-      line_count_left = line_count;
-      line_count_right = 0;
-    }
-    dp_right = (DATA_BL *)(hp_right->bh_data);
-    dp_left = (DATA_BL *)(hp_left->bh_data);
-    bnum_left = hp_left->bh_bnum;
-    bnum_right = hp_right->bh_bnum;
-    page_count_left = hp_left->bh_page_count;
-    page_count_right = hp_right->bh_page_count;
-
-    /*
-     * May move the new line into the right/new block.
-     */
-    if (!in_left) {
-      dp_right->db_txt_start -= len;
-      dp_right->db_free -= len + INDEX_SIZE;
-      dp_right->db_index[0] = dp_right->db_txt_start;
-      if (mark)
-        dp_right->db_index[0] |= DB_MARKED;
-
-      memmove((char *)dp_right + dp_right->db_txt_start,
-          line, (size_t)len);
-      ++line_count_right;
-    }
-    /*
-     * may move lines from the left/old block to the right/new one.
-     */
-    if (lines_moved) {
-      /*
-       */
-      dp_right->db_txt_start -= data_moved;
-      dp_right->db_free -= total_moved;
-      memmove((char *)dp_right + dp_right->db_txt_start,
-          (char *)dp_left + dp_left->db_txt_start,
-          (size_t)data_moved);
-      offset = dp_right->db_txt_start - dp_left->db_txt_start;
-      dp_left->db_txt_start += data_moved;
-      dp_left->db_free += total_moved;
-
-      /*
-       * update indexes in the new block
-       */
-      for (to = line_count_right, from = db_idx + 1;
-           from < line_count_left; ++from, ++to)
-        dp_right->db_index[to] = dp->db_index[from] + offset;
-      line_count_right += lines_moved;
-      line_count_left -= lines_moved;
-    }
-
-    /*
-     * May move the new line into the left (old or new) block.
-     */
-    if (in_left) {
-      dp_left->db_txt_start -= len;
-      dp_left->db_free -= len + INDEX_SIZE;
-      dp_left->db_index[line_count_left] = dp_left->db_txt_start;
-      if (mark)
-        dp_left->db_index[line_count_left] |= DB_MARKED;
-      memmove((char *)dp_left + dp_left->db_txt_start,
-          line, (size_t)len);
-      ++line_count_left;
-    }
-
-    if (db_idx < 0) {           /* left block is new */
-      lnum_left = lnum + 1;
-      lnum_right = 0;
-    } else {                  /* right block is new */
-      lnum_left = 0;
-      if (in_left)
-        lnum_right = lnum + 2;
-      else
-        lnum_right = lnum + 1;
-    }
-    dp_left->db_line_count = line_count_left;
-    dp_right->db_line_count = line_count_right;
-
-    /*
-     * release the two data blocks
-     * The new one (hp_new) already has a correct blocknumber.
-     * The old one (hp, in ml_locked) gets a positive blocknumber if
-     * we changed it and we are not editing a new file.
-     */
-    if (lines_moved || in_left)
-      buf->b_ml.ml_flags |= ML_LOCKED_DIRTY;
-    if (!newfile && db_idx >= 0 && in_left)
-      buf->b_ml.ml_flags |= ML_LOCKED_POS;
-    mf_put(mfp, hp_new, TRUE, FALSE);
-
-    /*
-     * flush the old data block
-     * set ml_locked_lineadd to 0, because the updating of the
-     * pointer blocks is done below
-     */
-    lineadd = buf->b_ml.ml_locked_lineadd;
-    buf->b_ml.ml_locked_lineadd = 0;
-    ml_find_line(buf, (linenr_T)0, ML_FLUSH);       /* flush data block */
-
-    /*
-     * update pointer blocks for the new data block
-     */
-    for (stack_idx = buf->b_ml.ml_stack_top - 1; stack_idx >= 0;
-         --stack_idx) {
-      ip = &(buf->b_ml.ml_stack[stack_idx]);
-      pb_idx = ip->ip_index;
-      if ((hp = mf_get(mfp, ip->ip_bnum, 1)) == NULL)
-        return FAIL;
-      pp = (PTR_BL *)(hp->bh_data);         /* must be pointer block */
-      if (pp->pb_id != PTR_ID) {
-        EMSG(_("E317: pointer block id wrong 3"));
-        mf_put(mfp, hp, FALSE, FALSE);
-        return FAIL;
-      }
-      /*
-       * TODO: If the pointer block is full and we are adding at the end
-       * try to insert in front of the next block
-       */
-      /* block not full, add one entry */
-      if (pp->pb_count < pp->pb_count_max) {
-        if (pb_idx + 1 < (int)pp->pb_count)
-          memmove(&pp->pb_pointer[pb_idx + 2],
-              &pp->pb_pointer[pb_idx + 1],
-              (size_t)(pp->pb_count - pb_idx - 1) * sizeof(PTR_EN));
-        ++pp->pb_count;
-        pp->pb_pointer[pb_idx].pe_line_count = line_count_left;
-        pp->pb_pointer[pb_idx].pe_bnum = bnum_left;
-        pp->pb_pointer[pb_idx].pe_page_count = page_count_left;
-        pp->pb_pointer[pb_idx + 1].pe_line_count = line_count_right;
-        pp->pb_pointer[pb_idx + 1].pe_bnum = bnum_right;
-        pp->pb_pointer[pb_idx + 1].pe_page_count = page_count_right;
-
-        if (lnum_left != 0)
-          pp->pb_pointer[pb_idx].pe_old_lnum = lnum_left;
-        if (lnum_right != 0)
-          pp->pb_pointer[pb_idx + 1].pe_old_lnum = lnum_right;
-
-        mf_put(mfp, hp, TRUE, FALSE);
-        buf->b_ml.ml_stack_top = stack_idx + 1;             /* truncate stack */
-
-        if (lineadd) {
-          --(buf->b_ml.ml_stack_top);
-          /* fix line count for rest of blocks in the stack */
-          ml_lineadd(buf, lineadd);
-          /* fix stack itself */
-          buf->b_ml.ml_stack[buf->b_ml.ml_stack_top].ip_high +=
-            lineadd;
-          ++(buf->b_ml.ml_stack_top);
-        }
-
-        /*
-         * We are finished, break the loop here.
-         */
-        break;
-      } else {                        /* pointer block full */
-        /*
-         * split the pointer block
-         * allocate a new pointer block
-         * move some of the pointer into the new block
-         * prepare for updating the parent block
-         */
-        for (;; ) {             /* do this twice when splitting block 1 */
-          hp_new = ml_new_ptr(mfp);
-          if (hp_new == NULL)               /* TODO: try to fix tree */
-            return FAIL;
-          pp_new = (PTR_BL *)(hp_new->bh_data);
-
-          if (hp->bh_bnum != 1)
-            break;
-
-          /*
-           * if block 1 becomes full the tree is given an extra level
-           * The pointers from block 1 are moved into the new block.
-           * block 1 is updated to point to the new block
-           * then continue to split the new block
-           */
-          memmove(pp_new, pp, (size_t)page_size);
-          pp->pb_count = 1;
-          pp->pb_pointer[0].pe_bnum = hp_new->bh_bnum;
-          pp->pb_pointer[0].pe_line_count = buf->b_ml.ml_line_count;
-          pp->pb_pointer[0].pe_old_lnum = 1;
-          pp->pb_pointer[0].pe_page_count = 1;
-          mf_put(mfp, hp, TRUE, FALSE);             /* release block 1 */
-          hp = hp_new;                          /* new block is to be split */
-          pp = pp_new;
-          CHECK(stack_idx != 0, _("stack_idx should be 0"));
-          ip->ip_index = 0;
-          ++stack_idx;                  /* do block 1 again later */
-        }
-        /*
-         * move the pointers after the current one to the new block
-         * If there are none, the new entry will be in the new block.
-         */
-        total_moved = pp->pb_count - pb_idx - 1;
-        if (total_moved) {
-          memmove(&pp_new->pb_pointer[0],
-              &pp->pb_pointer[pb_idx + 1],
-              (size_t)(total_moved) * sizeof(PTR_EN));
-          pp_new->pb_count = total_moved;
-          pp->pb_count -= total_moved - 1;
-          pp->pb_pointer[pb_idx + 1].pe_bnum = bnum_right;
-          pp->pb_pointer[pb_idx + 1].pe_line_count = line_count_right;
-          pp->pb_pointer[pb_idx + 1].pe_page_count = page_count_right;
-          if (lnum_right)
-            pp->pb_pointer[pb_idx + 1].pe_old_lnum = lnum_right;
-        } else {
-          pp_new->pb_count = 1;
-          pp_new->pb_pointer[0].pe_bnum = bnum_right;
-          pp_new->pb_pointer[0].pe_line_count = line_count_right;
-          pp_new->pb_pointer[0].pe_page_count = page_count_right;
-          pp_new->pb_pointer[0].pe_old_lnum = lnum_right;
-        }
-        pp->pb_pointer[pb_idx].pe_bnum = bnum_left;
-        pp->pb_pointer[pb_idx].pe_line_count = line_count_left;
-        pp->pb_pointer[pb_idx].pe_page_count = page_count_left;
-        if (lnum_left)
-          pp->pb_pointer[pb_idx].pe_old_lnum = lnum_left;
-        lnum_left = 0;
-        lnum_right = 0;
-
-        /*
-         * recompute line counts
-         */
-        line_count_right = 0;
-        for (i = 0; i < (int)pp_new->pb_count; ++i)
-          line_count_right += pp_new->pb_pointer[i].pe_line_count;
-        line_count_left = 0;
-        for (i = 0; i < (int)pp->pb_count; ++i)
-          line_count_left += pp->pb_pointer[i].pe_line_count;
-
-        bnum_left = hp->bh_bnum;
-        bnum_right = hp_new->bh_bnum;
-        page_count_left = 1;
-        page_count_right = 1;
-        mf_put(mfp, hp, TRUE, FALSE);
-        mf_put(mfp, hp_new, TRUE, FALSE);
-      }
-    }
-
-    /*
-     * Safety check: fallen out of for loop?
-     */
-    if (stack_idx < 0) {
-      EMSG(_("E318: Updated too many blocks?"));
-      buf->b_ml.ml_stack_top = 0;       /* invalidate stack */
-    }
-  }
-
-  /* The line was inserted below 'lnum' */
-  ml_updatechunk(buf, lnum + 1, (long)len, ML_CHNK_ADDLINE);
-  return OK;
-}
-
-/*
- * Replace line lnum, with buffering, in current buffer.
- *
- * If "copy" is TRUE, make a copy of the line, otherwise the line has been
- * copied to allocated memory already.
- *
- * Check: The caller of this function should probably also call
- * changed_lines(), unless update_screen(NOT_VALID) is used.
- *
- * return FAIL for failure, OK otherwise
- */
-int ml_replace(linenr_T lnum, char_u *line, int copy)
-{
-  if (line == NULL)             /* just checking... */
-    return FAIL;
-
-  /* When starting up, we might still need to create the memfile */
-  if (curbuf->b_ml.ml_mfp == NULL && open_buffer(FALSE, NULL, 0) == FAIL)
-    return FAIL;
-
-  if (copy && (line = vim_strsave(line)) == NULL)   /* allocate memory */
-    return FAIL;
-  if (curbuf->b_ml.ml_line_lnum != lnum)            /* other line buffered */
-    ml_flush_line(curbuf);                          /* flush it */
-  else if (curbuf->b_ml.ml_flags & ML_LINE_DIRTY)   /* same line allocated */
-    free(curbuf->b_ml.ml_line_ptr);             /* free it */
-  curbuf->b_ml.ml_line_ptr = line;
-  curbuf->b_ml.ml_line_lnum = lnum;
-  curbuf->b_ml.ml_flags = (curbuf->b_ml.ml_flags | ML_LINE_DIRTY) & ~ML_EMPTY;
-
-  return OK;
-}
-
-/*
- * Delete line 'lnum' in the current buffer.
- *
- * Check: The caller of this function should probably also call
- * deleted_lines() after this.
- *
- * return FAIL for failure, OK otherwise
- */
-int ml_delete(linenr_T lnum, int message)
-{
-  ml_flush_line(curbuf);
-  return ml_delete_int(curbuf, lnum, message);
-}
-
-static int ml_delete_int(buf_T *buf, linenr_T lnum, int message)
-{
-  bhdr_T      *hp;
-  memfile_T   *mfp;
-  DATA_BL     *dp;
-  PTR_BL      *pp;
-  infoptr_T   *ip;
-  int count;                /* number of entries in block */
-  int idx;
-  int stack_idx;
-  int text_start;
-  int line_start;
-  long line_size;
-  int i;
-
-  if (lnum < 1 || lnum > buf->b_ml.ml_line_count)
-    return FAIL;
-
-  if (lowest_marked && lowest_marked > lnum)
-    lowest_marked--;
-
-  /*
-   * If the file becomes empty the last line is replaced by an empty line.
-   */
-  if (buf->b_ml.ml_line_count == 1) {       /* file becomes empty */
-    if (message
-        )
-      set_keep_msg((char_u *)_(no_lines_msg), 0);
-
-    /* FEAT_BYTEOFF already handled in there, don't worry 'bout it below */
-    i = ml_replace((linenr_T)1, (char_u *)"", TRUE);
-    buf->b_ml.ml_flags |= ML_EMPTY;
-
-    return i;
-  }
-
-  /*
-   * find the data block containing the line
-   * This also fills the stack with the blocks from the root to the data block
-   * This also releases any locked block.
-   */
-  mfp = buf->b_ml.ml_mfp;
-  if (mfp == NULL)
-    return FAIL;
-
-  if ((hp = ml_find_line(buf, lnum, ML_DELETE)) == NULL)
-    return FAIL;
-
-  dp = (DATA_BL *)(hp->bh_data);
-  /* compute line count before the delete */
-  count = (long)(buf->b_ml.ml_locked_high)
-          - (long)(buf->b_ml.ml_locked_low) + 2;
-  idx = lnum - buf->b_ml.ml_locked_low;
-
-  --buf->b_ml.ml_line_count;
-
-  line_start = ((dp->db_index[idx]) & DB_INDEX_MASK);
-  if (idx == 0)                 /* first line in block, text at the end */
-    line_size = dp->db_txt_end - line_start;
-  else
-    line_size = ((dp->db_index[idx - 1]) & DB_INDEX_MASK) - line_start;
-
-
-  /*
-   * special case: If there is only one line in the data block it becomes empty.
-   * Then we have to remove the entry, pointing to this data block, from the
-   * pointer block. If this pointer block also becomes empty, we go up another
-   * block, and so on, up to the root if necessary.
-   * The line counts in the pointer blocks have already been adjusted by
-   * ml_find_line().
-   */
-  if (count == 1) {
-    mf_free(mfp, hp);           /* free the data block */
-    buf->b_ml.ml_locked = NULL;
-
-    for (stack_idx = buf->b_ml.ml_stack_top - 1; stack_idx >= 0;
-         --stack_idx) {
-      buf->b_ml.ml_stack_top = 0;           /* stack is invalid when failing */
-      ip = &(buf->b_ml.ml_stack[stack_idx]);
-      idx = ip->ip_index;
-      if ((hp = mf_get(mfp, ip->ip_bnum, 1)) == NULL)
-        return FAIL;
-      pp = (PTR_BL *)(hp->bh_data);         /* must be pointer block */
-      if (pp->pb_id != PTR_ID) {
-        EMSG(_("E317: pointer block id wrong 4"));
-        mf_put(mfp, hp, FALSE, FALSE);
-        return FAIL;
-      }
-      count = --(pp->pb_count);
-      if (count == 0)               /* the pointer block becomes empty! */
-        mf_free(mfp, hp);
-      else {
-        if (count != idx)               /* move entries after the deleted one */
-          memmove(&pp->pb_pointer[idx], &pp->pb_pointer[idx + 1],
-              (size_t)(count - idx) * sizeof(PTR_EN));
-        mf_put(mfp, hp, TRUE, FALSE);
-
-        buf->b_ml.ml_stack_top = stack_idx;             /* truncate stack */
-        /* fix line count for rest of blocks in the stack */
-        if (buf->b_ml.ml_locked_lineadd != 0) {
-          ml_lineadd(buf, buf->b_ml.ml_locked_lineadd);
-          buf->b_ml.ml_stack[buf->b_ml.ml_stack_top].ip_high +=
-            buf->b_ml.ml_locked_lineadd;
-        }
-        ++(buf->b_ml.ml_stack_top);
-
-        break;
-      }
-    }
-    CHECK(stack_idx < 0, _("deleted block 1?"));
-  } else {
-    /*
-     * delete the text by moving the next lines forwards
-     */
-    text_start = dp->db_txt_start;
-    memmove((char *)dp + text_start + line_size,
-        (char *)dp + text_start, (size_t)(line_start - text_start));
-
-    /*
-     * delete the index by moving the next indexes backwards
-     * Adjust the indexes for the text movement.
-     */
-    for (i = idx; i < count - 1; ++i)
-      dp->db_index[i] = dp->db_index[i + 1] + line_size;
-
-    dp->db_free += line_size + INDEX_SIZE;
-    dp->db_txt_start += line_size;
-    --(dp->db_line_count);
-
-    /*
-     * mark the block dirty and make sure it is in the file (for recovery)
-     */
-    buf->b_ml.ml_flags |= (ML_LOCKED_DIRTY | ML_LOCKED_POS);
-  }
-
-  ml_updatechunk(buf, lnum, line_size, ML_CHNK_DELLINE);
-  return OK;
-}
-
-/*
- * set the B_MARKED flag for line 'lnum'
- */
-void ml_setmarked(linenr_T lnum)
-{
-  bhdr_T    *hp;
-  DATA_BL *dp;
-  /* invalid line number */
-  if (lnum < 1 || lnum > curbuf->b_ml.ml_line_count
-      || curbuf->b_ml.ml_mfp == NULL)
-    return;                         /* give error message? */
-
-  if (lowest_marked == 0 || lowest_marked > lnum)
-    lowest_marked = lnum;
-
-  /*
-   * find the data block containing the line
-   * This also fills the stack with the blocks from the root to the data block
-   * This also releases any locked block.
-   */
-  if ((hp = ml_find_line(curbuf, lnum, ML_FIND)) == NULL)
-    return;                 /* give error message? */
-
-  dp = (DATA_BL *)(hp->bh_data);
-  dp->db_index[lnum - curbuf->b_ml.ml_locked_low] |= DB_MARKED;
-  curbuf->b_ml.ml_flags |= ML_LOCKED_DIRTY;
-}
-
-/*
- * find the first line with its B_MARKED flag set
- */
-linenr_T ml_firstmarked(void)
-{
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-  linenr_T lnum;
-  int i;
-
-  if (curbuf->b_ml.ml_mfp == NULL)
-    return (linenr_T) 0;
-
-  /*
-   * The search starts with lowest_marked line. This is the last line where
-   * a mark was found, adjusted by inserting/deleting lines.
-   */
-  for (lnum = lowest_marked; lnum <= curbuf->b_ml.ml_line_count; ) {
-    /*
-     * Find the data block containing the line.
-     * This also fills the stack with the blocks from the root to the data
-     * block This also releases any locked block.
-     */
-    if ((hp = ml_find_line(curbuf, lnum, ML_FIND)) == NULL)
-      return (linenr_T)0;                   /* give error message? */
-
-    dp = (DATA_BL *)(hp->bh_data);
-
-    for (i = lnum - curbuf->b_ml.ml_locked_low;
-         lnum <= curbuf->b_ml.ml_locked_high; ++i, ++lnum)
-      if ((dp->db_index[i]) & DB_MARKED) {
-        (dp->db_index[i]) &= DB_INDEX_MASK;
-        curbuf->b_ml.ml_flags |= ML_LOCKED_DIRTY;
-        lowest_marked = lnum + 1;
-        return lnum;
-      }
-  }
-
-  return (linenr_T) 0;
-}
-
-/*
- * clear all DB_MARKED flags
- */
-void ml_clearmarked(void)
-{
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-  linenr_T lnum;
-  int i;
-
-  if (curbuf->b_ml.ml_mfp == NULL)          /* nothing to do */
-    return;
-
-  /*
-   * The search starts with line lowest_marked.
-   */
-  for (lnum = lowest_marked; lnum <= curbuf->b_ml.ml_line_count; ) {
-    /*
-     * Find the data block containing the line.
-     * This also fills the stack with the blocks from the root to the data
-     * block and releases any locked block.
-     */
-    if ((hp = ml_find_line(curbuf, lnum, ML_FIND)) == NULL)
-      return;                   /* give error message? */
-
-    dp = (DATA_BL *)(hp->bh_data);
-
-    for (i = lnum - curbuf->b_ml.ml_locked_low;
-         lnum <= curbuf->b_ml.ml_locked_high; ++i, ++lnum)
-      if ((dp->db_index[i]) & DB_MARKED) {
-        (dp->db_index[i]) &= DB_INDEX_MASK;
-        curbuf->b_ml.ml_flags |= ML_LOCKED_DIRTY;
-      }
-  }
-
-  lowest_marked = 0;
-  return;
-}
-
-/*
- * flush ml_line if necessary
- */
-static void ml_flush_line(buf_T *buf)
-{
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-  linenr_T lnum;
-  char_u      *new_line;
-  char_u      *old_line;
-  colnr_T new_len;
-  int old_len;
-  int extra;
-  int idx;
-  int start;
-  int count;
-  int i;
-  static int entered = FALSE;
-
-  if (buf->b_ml.ml_line_lnum == 0 || buf->b_ml.ml_mfp == NULL)
-    return;             /* nothing to do */
-
-  if (buf->b_ml.ml_flags & ML_LINE_DIRTY) {
-    /* This code doesn't work recursively. */
-    if (entered)
-      return;
-    entered = TRUE;
-
-    lnum = buf->b_ml.ml_line_lnum;
-    new_line = buf->b_ml.ml_line_ptr;
-
-    hp = ml_find_line(buf, lnum, ML_FIND);
-    if (hp == NULL)
-      EMSGN(_("E320: Cannot find line %" PRId64), lnum);
-    else {
-      dp = (DATA_BL *)(hp->bh_data);
-      idx = lnum - buf->b_ml.ml_locked_low;
-      start = ((dp->db_index[idx]) & DB_INDEX_MASK);
-      old_line = (char_u *)dp + start;
-      if (idx == 0)             /* line is last in block */
-        old_len = dp->db_txt_end - start;
-      else                      /* text of previous line follows */
-        old_len = (dp->db_index[idx - 1] & DB_INDEX_MASK) - start;
-      new_len = (colnr_T)STRLEN(new_line) + 1;
-      extra = new_len - old_len;            /* negative if lines gets smaller */
-
-      /*
-       * if new line fits in data block, replace directly
-       */
-      if ((int)dp->db_free >= extra) {
-        /* if the length changes and there are following lines */
-        count = buf->b_ml.ml_locked_high - buf->b_ml.ml_locked_low + 1;
-        if (extra != 0 && idx < count - 1) {
-          /* move text of following lines */
-          memmove((char *)dp + dp->db_txt_start - extra,
-              (char *)dp + dp->db_txt_start,
-              (size_t)(start - dp->db_txt_start));
-
-          /* adjust pointers of this and following lines */
-          for (i = idx + 1; i < count; ++i)
-            dp->db_index[i] -= extra;
-        }
-        dp->db_index[idx] -= extra;
-
-        /* adjust free space */
-        dp->db_free -= extra;
-        dp->db_txt_start -= extra;
-
-        /* copy new line into the data block */
-        memmove(old_line - extra, new_line, (size_t)new_len);
-        buf->b_ml.ml_flags |= (ML_LOCKED_DIRTY | ML_LOCKED_POS);
-        /* The else case is already covered by the insert and delete */
-        ml_updatechunk(buf, lnum, (long)extra, ML_CHNK_UPDLINE);
-      } else {
-        /*
-         * Cannot do it in one data block: Delete and append.
-         * Append first, because ml_delete_int() cannot delete the
-         * last line in a buffer, which causes trouble for a buffer
-         * that has only one line.
-         * Don't forget to copy the mark!
-         */
-        /* How about handling errors??? */
-        (void)ml_append_int(buf, lnum, new_line, new_len, FALSE,
-            (dp->db_index[idx] & DB_MARKED));
-        (void)ml_delete_int(buf, lnum, FALSE);
-      }
-    }
-    free(new_line);
-
-    entered = FALSE;
-  }
-
-  buf->b_ml.ml_line_lnum = 0;
-}
-
-/*
- * create a new, empty, data block
- */
-static bhdr_T *ml_new_data(memfile_T *mfp, int negative, int page_count)
-{
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-
-  if ((hp = mf_new(mfp, negative, page_count)) == NULL)
-    return NULL;
-
-  dp = (DATA_BL *)(hp->bh_data);
-  dp->db_id = DATA_ID;
-  dp->db_txt_start = dp->db_txt_end = page_count * mfp->mf_page_size;
-  dp->db_free = dp->db_txt_start - HEADER_SIZE;
-  dp->db_line_count = 0;
-
-  return hp;
-}
-
-/*
- * create a new, empty, pointer block
- */
-static bhdr_T *ml_new_ptr(memfile_T *mfp)
-{
-  bhdr_T      *hp;
-  PTR_BL      *pp;
-
-  if ((hp = mf_new(mfp, FALSE, 1)) == NULL)
-    return NULL;
-
-  pp = (PTR_BL *)(hp->bh_data);
-  pp->pb_id = PTR_ID;
-  pp->pb_count = 0;
-  pp->pb_count_max = (mfp->mf_page_size - sizeof(PTR_BL)) / sizeof(PTR_EN) + 1;
-
-  return hp;
-}
-
-/*
- * lookup line 'lnum' in a memline
- *
- *   action: if ML_DELETE or ML_INSERT the line count is updated while searching
- *	     if ML_FLUSH only flush a locked block
- *	     if ML_FIND just find the line
- *
- * If the block was found it is locked and put in ml_locked.
- * The stack is updated to lead to the locked block. The ip_high field in
- * the stack is updated to reflect the last line in the block AFTER the
- * insert or delete, also if the pointer block has not been updated yet. But
- * if ml_locked != NULL ml_locked_lineadd must be added to ip_high.
- *
- * return: NULL for failure, pointer to block header otherwise
- */
-static bhdr_T *ml_find_line(buf_T *buf, linenr_T lnum, int action)
-{
-  DATA_BL     *dp;
-  PTR_BL      *pp;
-  infoptr_T   *ip;
-  bhdr_T      *hp;
-  memfile_T   *mfp;
-  linenr_T t;
-  blocknr_T bnum, bnum2;
-  int dirty;
-  linenr_T low, high;
-  int top;
-  int page_count;
-  int idx;
-
-  mfp = buf->b_ml.ml_mfp;
-
-  /*
-   * If there is a locked block check if the wanted line is in it.
-   * If not, flush and release the locked block.
-   * Don't do this for ML_INSERT_SAME, because the stack need to be updated.
-   * Don't do this for ML_FLUSH, because we want to flush the locked block.
-   * Don't do this when 'swapfile' is reset, we want to load all the blocks.
-   */
-  if (buf->b_ml.ml_locked) {
-    if (ML_SIMPLE(action)
-        && buf->b_ml.ml_locked_low <= lnum
-        && buf->b_ml.ml_locked_high >= lnum
-        && !mf_dont_release) {
-      /* remember to update pointer blocks and stack later */
-      if (action == ML_INSERT) {
-        ++(buf->b_ml.ml_locked_lineadd);
-        ++(buf->b_ml.ml_locked_high);
-      } else if (action == ML_DELETE) {
-        --(buf->b_ml.ml_locked_lineadd);
-        --(buf->b_ml.ml_locked_high);
-      }
-      return buf->b_ml.ml_locked;
-    }
-
-    mf_put(mfp, buf->b_ml.ml_locked, buf->b_ml.ml_flags & ML_LOCKED_DIRTY,
-        buf->b_ml.ml_flags & ML_LOCKED_POS);
-    buf->b_ml.ml_locked = NULL;
-
-    /*
-     * If lines have been added or deleted in the locked block, need to
-     * update the line count in pointer blocks.
-     */
-    if (buf->b_ml.ml_locked_lineadd != 0)
-      ml_lineadd(buf, buf->b_ml.ml_locked_lineadd);
-  }
-
-  if (action == ML_FLUSH)           /* nothing else to do */
-    return NULL;
-
-  bnum = 1;                         /* start at the root of the tree */
-  page_count = 1;
-  low = 1;
-  high = buf->b_ml.ml_line_count;
-
-  if (action == ML_FIND) {      /* first try stack entries */
-    for (top = buf->b_ml.ml_stack_top - 1; top >= 0; --top) {
-      ip = &(buf->b_ml.ml_stack[top]);
-      if (ip->ip_low <= lnum && ip->ip_high >= lnum) {
-        bnum = ip->ip_bnum;
-        low = ip->ip_low;
-        high = ip->ip_high;
-        buf->b_ml.ml_stack_top = top;           /* truncate stack at prev entry */
-        break;
-      }
-    }
-    if (top < 0)
-      buf->b_ml.ml_stack_top = 0;               /* not found, start at the root */
-  } else        /* ML_DELETE or ML_INSERT */
-    buf->b_ml.ml_stack_top = 0;         /* start at the root */
-
-  /*
-   * search downwards in the tree until a data block is found
-   */
-  for (;; ) {
-    if ((hp = mf_get(mfp, bnum, page_count)) == NULL)
-      goto error_noblock;
-
-    /*
-     * update high for insert/delete
-     */
-    if (action == ML_INSERT)
-      ++high;
-    else if (action == ML_DELETE)
-      --high;
-
-    dp = (DATA_BL *)(hp->bh_data);
-    if (dp->db_id == DATA_ID) {         /* data block */
-      buf->b_ml.ml_locked = hp;
-      buf->b_ml.ml_locked_low = low;
-      buf->b_ml.ml_locked_high = high;
-      buf->b_ml.ml_locked_lineadd = 0;
-      buf->b_ml.ml_flags &= ~(ML_LOCKED_DIRTY | ML_LOCKED_POS);
-      return hp;
-    }
-
-    pp = (PTR_BL *)(dp);                /* must be pointer block */
-    if (pp->pb_id != PTR_ID) {
-      EMSG(_("E317: pointer block id wrong"));
-      goto error_block;
-    }
-
-    top = ml_add_stack(buf);  // add new entry to stack
-    ip = &(buf->b_ml.ml_stack[top]);
-    ip->ip_bnum = bnum;
-    ip->ip_low = low;
-    ip->ip_high = high;
-    ip->ip_index = -1;                  /* index not known yet */
-
-    dirty = FALSE;
-    for (idx = 0; idx < (int)pp->pb_count; ++idx) {
-      t = pp->pb_pointer[idx].pe_line_count;
-      CHECK(t == 0, _("pe_line_count is zero"));
-      if ((low += t) > lnum) {
-        ip->ip_index = idx;
-        bnum = pp->pb_pointer[idx].pe_bnum;
-        page_count = pp->pb_pointer[idx].pe_page_count;
-        high = low - 1;
-        low -= t;
-
-        /*
-         * a negative block number may have been changed
-         */
-        if (bnum < 0) {
-          bnum2 = mf_trans_del(mfp, bnum);
-          if (bnum != bnum2) {
-            bnum = bnum2;
-            pp->pb_pointer[idx].pe_bnum = bnum;
-            dirty = TRUE;
-          }
-        }
-
-        break;
-      }
-    }
-    if (idx >= (int)pp->pb_count) {         /* past the end: something wrong! */
-      if (lnum > buf->b_ml.ml_line_count)
-        EMSGN(_("E322: line number out of range: %" PRId64 " past the end"),
-            lnum - buf->b_ml.ml_line_count);
-
-      else
-        EMSGN(_("E323: line count wrong in block %" PRId64), bnum);
-      goto error_block;
-    }
-    if (action == ML_DELETE) {
-      pp->pb_pointer[idx].pe_line_count--;
-      dirty = TRUE;
-    } else if (action == ML_INSERT) {
-      pp->pb_pointer[idx].pe_line_count++;
-      dirty = TRUE;
-    }
-    mf_put(mfp, hp, dirty, FALSE);
-  }
-
-error_block:
-  mf_put(mfp, hp, FALSE, FALSE);
-error_noblock:
-  /*
-   * If action is ML_DELETE or ML_INSERT we have to correct the tree for
-   * the incremented/decremented line counts, because there won't be a line
-   * inserted/deleted after all.
-   */
-  if (action == ML_DELETE)
-    ml_lineadd(buf, 1);
-  else if (action == ML_INSERT)
-    ml_lineadd(buf, -1);
-  buf->b_ml.ml_stack_top = 0;
-  return NULL;
-}
-
-/*
- * add an entry to the info pointer stack
- *
- * return number of the new entry
- */
-static int ml_add_stack(buf_T *buf)
-{
-  int top = buf->b_ml.ml_stack_top;
-
-  /* may have to increase the stack size */
-  if (top == buf->b_ml.ml_stack_size) {
-    CHECK(top > 0, _("Stack size increases"));     /* more than 5 levels??? */
-
-    infoptr_T *newstack = xmalloc(sizeof(infoptr_T) *
-                                    (buf->b_ml.ml_stack_size + STACK_INCR));
-    memmove(newstack, buf->b_ml.ml_stack, (size_t)top * sizeof(infoptr_T));
-    free(buf->b_ml.ml_stack);
-    buf->b_ml.ml_stack = newstack;
-    buf->b_ml.ml_stack_size += STACK_INCR;
-  }
-
-  buf->b_ml.ml_stack_top++;
-  return top;
-}
-
-/*
- * Update the pointer blocks on the stack for inserted/deleted lines.
- * The stack itself is also updated.
- *
- * When a insert/delete line action fails, the line is not inserted/deleted,
- * but the pointer blocks have already been updated. That is fixed here by
- * walking through the stack.
- *
- * Count is the number of lines added, negative if lines have been deleted.
- */
-static void ml_lineadd(buf_T *buf, int count)
-{
-  int idx;
-  infoptr_T   *ip;
-  PTR_BL      *pp;
-  memfile_T   *mfp = buf->b_ml.ml_mfp;
-  bhdr_T      *hp;
-
-  for (idx = buf->b_ml.ml_stack_top - 1; idx >= 0; --idx) {
-    ip = &(buf->b_ml.ml_stack[idx]);
-    if ((hp = mf_get(mfp, ip->ip_bnum, 1)) == NULL)
-      break;
-    pp = (PTR_BL *)(hp->bh_data);       /* must be pointer block */
-    if (pp->pb_id != PTR_ID) {
-      mf_put(mfp, hp, FALSE, FALSE);
-      EMSG(_("E317: pointer block id wrong 2"));
-      break;
-    }
-    pp->pb_pointer[ip->ip_index].pe_line_count += count;
-    ip->ip_high += count;
-    mf_put(mfp, hp, TRUE, FALSE);
-  }
-}
-
-#if defined(HAVE_READLINK) || defined(PROTO)
-/*
- * Resolve a symlink in the last component of a file name.
- * Note that f_resolve() does it for every part of the path, we don't do that
- * here.
- * If it worked returns OK and the resolved link in "buf[MAXPATHL]".
- * Otherwise returns FAIL.
- */
-int resolve_symlink(char_u *fname, char_u *buf)
-{
-  char_u tmp[MAXPATHL];
-  int ret;
-  int depth = 0;
-
-  if (fname == NULL)
-    return FAIL;
-
-  /* Put the result so far in tmp[], starting with the original name. */
-  vim_strncpy(tmp, fname, MAXPATHL - 1);
-
-  for (;; ) {
-    /* Limit symlink depth to 100, catch recursive loops. */
-    if (++depth == 100) {
-      EMSG2(_("E773: Symlink loop for \"%s\""), fname);
-      return FAIL;
-    }
-
-    ret = readlink((char *)tmp, (char *)buf, MAXPATHL - 1);
-    if (ret <= 0) {
-      if (errno == EINVAL || errno == ENOENT) {
-        /* Found non-symlink or not existing file, stop here.
-         * When at the first level use the unmodified name, skip the
-         * call to vim_FullName(). */
-        if (depth == 1)
-          return FAIL;
-
-        /* Use the resolved name in tmp[]. */
-        break;
-      }
-
-      /* There must be some error reading links, use original name. */
-      return FAIL;
-    }
-    buf[ret] = NUL;
-
-    /*
-     * Check whether the symlink is relative or absolute.
-     * If it's relative, build a new path based on the directory
-     * portion of the filename (if any) and the path the symlink
-     * points to.
-     */
-    if (path_is_absolute_path(buf))
-      STRCPY(tmp, buf);
-    else {
-      char_u *tail;
-
-      tail = path_tail(tmp);
-      if (STRLEN(tail) + STRLEN(buf) >= MAXPATHL)
-        return FAIL;
-      STRCPY(tail, buf);
-    }
-  }
-
-  /*
-   * Try to resolve the full name of the file so that the swapfile name will
-   * be consistent even when opening a relative symlink from different
-   * working directories.
-   */
-  return vim_FullName(tmp, buf, MAXPATHL, TRUE);
-}
-#endif
-
-/*
- * Make swap file name out of the file name and a directory name.
- * Returns pointer to allocated memory or NULL.
- */
-char_u *makeswapname(char_u *fname, char_u *ffname, buf_T *buf, char_u *dir_name)
-{
-  char_u      *r, *s;
-  char_u      *fname_res = fname;
-#ifdef HAVE_READLINK
-  char_u fname_buf[MAXPATHL];
-#endif
-
-#if defined(UNIX) || defined(WIN3264)  /* Need _very_ long file names */
-  s = dir_name + STRLEN(dir_name);
-  if (after_pathsep(dir_name, s) && s[-1] == s[-2]) { /* Ends with '//', Use Full path */
-    r = NULL;
-    if ((s = make_percent_swname(dir_name, fname)) != NULL) {
-      r = modname(s, (char_u *)".swp", FALSE);
-      free(s);
-    }
-    return r;
-  }
-#endif
-
-#ifdef HAVE_READLINK
-  /* Expand symlink in the file name, so that we put the swap file with the
-   * actual file instead of with the symlink. */
-  if (resolve_symlink(fname, fname_buf) == OK)
-    fname_res = fname_buf;
-#endif
-
-  // Prepend a '.' to the swap file name for the current directory.
-  r = modname(fname_res, (char_u *)".swp",
-              dir_name[0] == '.' && dir_name[1] == NUL);
-  if (r == NULL)            /* out of memory */
-    return NULL;
-
-  s = get_file_in_dir(r, dir_name);
-  free(r);
-  return s;
-}
-
-/*
- * Get file name to use for swap file or backup file.
- * Use the name of the edited file "fname" and an entry in the 'dir' or 'bdir'
- * option "dname".
- * - If "dname" is ".", return "fname" (swap file in dir of file).
- * - If "dname" starts with "./", insert "dname" in "fname" (swap file
- *   relative to dir of file).
- * - Otherwise, prepend "dname" to the tail of "fname" (swap file in specific
- *   dir).
- *
- * The return value is an allocated string and can be NULL.
- */
-char_u *
-get_file_in_dir (
-    char_u *fname,
-    char_u *dname         /* don't use "dirname", it is a global for Alpha */
-)
-{
-  char_u      *t;
-  char_u      *tail;
-  char_u      *retval;
-  int save_char;
-
-  tail = path_tail(fname);
-
-  if (dname[0] == '.' && dname[1] == NUL)
-    retval = vim_strsave(fname);
-  else if (dname[0] == '.' && vim_ispathsep(dname[1])) {
-    if (tail == fname)              /* no path before file name */
-      retval = concat_fnames(dname + 2, tail, TRUE);
-    else {
-      save_char = *tail;
-      *tail = NUL;
-      t = concat_fnames(fname, dname + 2, TRUE);
-      *tail = save_char;
-      retval = concat_fnames(t, tail, TRUE);
-      free(t);
-    }
-  } else {
-    retval = concat_fnames(dname, tail, TRUE);
-  }
-
-  return retval;
-}
-
-static void attention_message(buf_T *buf, char_u *fname);
-
-/*
- * Print the ATTENTION message: info about an existing swap file.
- */
-static void 
-attention_message (
-    buf_T *buf,           /* buffer being edited */
-    char_u *fname         /* swap file name */
-)
-{
-  time_t x, sx;
-  char        *p;
-
-  ++no_wait_return;
-  (void)EMSG(_("E325: ATTENTION"));
-  MSG_PUTS(_("\nFound a swap file by the name \""));
-  msg_home_replace(fname);
-  MSG_PUTS("\"\n");
-  sx = swapfile_info(fname);
-  MSG_PUTS(_("While opening file \""));
-  msg_outtrans(buf->b_fname);
-  MSG_PUTS("\"\n");
-  FileInfo file_info;
-  if (os_get_file_info((char *)buf->b_fname, &file_info)) {
-    MSG_PUTS(_("             dated: "));
-    x = file_info.stat.st_mtim.tv_sec;
-    p = ctime(&x);  // includes '\n'
-    if (p == NULL)
-      MSG_PUTS("(invalid)\n");
-    else
-      MSG_PUTS(p);
-    if (sx != 0 && x > sx)
-      MSG_PUTS(_("      NEWER than swap file!\n"));
-  }
-  /* Some of these messages are long to allow translation to
-   * other languages. */
-  MSG_PUTS(_(
-          "\n(1) Another program may be editing the same file.  If this is the case,\n    be careful not to end up with two different instances of the same\n    file when making changes."));
-  MSG_PUTS(_("  Quit, or continue with caution.\n"));
-  MSG_PUTS(_("(2) An edit session for this file crashed.\n"));
-  MSG_PUTS(_("    If this is the case, use \":recover\" or \"vim -r "));
-  msg_outtrans(buf->b_fname);
-  MSG_PUTS(_("\"\n    to recover the changes (see \":help recovery\").\n"));
-  MSG_PUTS(_("    If you did this already, delete the swap file \""));
-  msg_outtrans(fname);
-  MSG_PUTS(_("\"\n    to avoid this message.\n"));
-  cmdline_row = msg_row;
-  --no_wait_return;
-}
-
-static int do_swapexists(buf_T *buf, char_u *fname);
-
-/*
- * Trigger the SwapExists autocommands.
- * Returns a value for equivalent to do_dialog() (see below):
- * 0: still need to ask for a choice
- * 1: open read-only
- * 2: edit anyway
- * 3: recover
- * 4: delete it
- * 5: quit
- * 6: abort
- */
-static int do_swapexists(buf_T *buf, char_u *fname)
-{
-  set_vim_var_string(VV_SWAPNAME, fname, -1);
-  set_vim_var_string(VV_SWAPCHOICE, NULL, -1);
-
-  /* Trigger SwapExists autocommands with <afile> set to the file being
-   * edited.  Disallow changing directory here. */
-  ++allbuf_lock;
-  apply_autocmds(EVENT_SWAPEXISTS, buf->b_fname, NULL, FALSE, NULL);
-  --allbuf_lock;
-
-  set_vim_var_string(VV_SWAPNAME, NULL, -1);
-
-  switch (*get_vim_var_str(VV_SWAPCHOICE)) {
-  case 'o': return 1;
-  case 'e': return 2;
-  case 'r': return 3;
-  case 'd': return 4;
-  case 'q': return 5;
-  case 'a': return 6;
-  }
-
-  return 0;
-}
-
-/*
- * Find out what name to use for the swap file for buffer 'buf'.
- *
- * Several names are tried to find one that does not exist
- * Returns the name in allocated memory or NULL.
- * When out of memory "dirp" is set to NULL.
- *
- * Note: If BASENAMELEN is not correct, you will get error messages for
- *	 not being able to open the swap or undo file
- * Note: May trigger SwapExists autocmd, pointers may change!
- */
-static char_u *
-findswapname (
-    buf_T *buf,
-    char_u **dirp,             /* pointer to list of directories */
-    char_u *old_fname         /* don't give warning for this file name */
-)
-{
-  char_u      *fname;
-  int n;
-  char_u      *dir_name;
-  char_u      *buf_fname = buf->b_fname;
-
-  /*
-   * Isolate a directory name from *dirp and put it in dir_name.
-   * First allocate some memory to put the directory name in.
-   */
-  dir_name = alloc((unsigned)STRLEN(*dirp) + 1);
-  (void)copy_option_part(dirp, dir_name, 31000, ",");
-
-  /*
-   * we try different names until we find one that does not exist yet
-   */
-  if (dir_name == NULL)             /* out of memory */
-    fname = NULL;
-  else
-    fname = makeswapname(buf_fname, buf->b_ffname, buf, dir_name);
-
-  for (;; ) {
-    if (fname == NULL)          /* must be out of memory */
-      break;
-    if ((n = (int)STRLEN(fname)) == 0) {        /* safety check */
-      free(fname);
-      fname = NULL;
-      break;
-    }
-    // check if the swapfile already exists
-    // Extra security check: When a swap file is a symbolic link, this
-    // is most likely a symlink attack.
-    FileInfo file_info;
-    bool file_or_link_found = os_get_file_info_link((char *)fname, &file_info);
-    if (!file_or_link_found) {
-      break;
-    }
-
-    /*
-     * A file name equal to old_fname is OK to use.
-     */
-    if (old_fname != NULL && fnamecmp(fname, old_fname) == 0)
-      break;
-
-    /*
-     * get here when file already exists
-     */
-    if (fname[n - 2] == 'w' && fname[n - 1] == 'p') {   /* first try */
-      /*
-       * If we get here the ".swp" file really exists.
-       * Give an error message, unless recovering, no file name, we are
-       * viewing a help file or when the path of the file is different
-       * (happens when all .swp files are in one directory).
-       */
-      if (!recoverymode && buf_fname != NULL
-          && !buf->b_help && !(buf->b_flags & BF_DUMMY)) {
-        int fd;
-        struct block0 b0;
-        int differ = FALSE;
-
-        /*
-         * Try to read block 0 from the swap file to get the original
-         * file name (and inode number).
-         */
-        fd = mch_open((char *)fname, O_RDONLY, 0);
-        if (fd >= 0) {
-          if (read_eintr(fd, &b0, sizeof(b0)) == sizeof(b0)) {
-            /*
-             * If the swapfile has the same directory as the
-             * buffer don't compare the directory names, they can
-             * have a different mountpoint.
-             */
-            if (b0.b0_flags & B0_SAME_DIR) {
-              if (fnamecmp(path_tail(buf->b_ffname),
-                      path_tail(b0.b0_fname)) != 0
-                  || !same_directory(fname, buf->b_ffname)) {
-#ifdef CHECK_INODE
-                /* Symlinks may point to the same file even
-                 * when the name differs, need to check the
-                 * inode too. */
-                expand_env(b0.b0_fname, NameBuff, MAXPATHL);
-                if (fnamecmp_ino(buf->b_ffname, NameBuff,
-                        char_to_long(b0.b0_ino)))
-#endif
-                differ = TRUE;
-              }
-            } else {
-              /*
-               * The name in the swap file may be
-               * "~user/path/file".  Expand it first.
-               */
-              expand_env(b0.b0_fname, NameBuff, MAXPATHL);
-#ifdef CHECK_INODE
-              if (fnamecmp_ino(buf->b_ffname, NameBuff,
-                      char_to_long(b0.b0_ino)))
-                differ = TRUE;
-#else
-              if (fnamecmp(NameBuff, buf->b_ffname) != 0)
-                differ = TRUE;
-#endif
-            }
-          }
-          close(fd);
-        }
-
-        /* give the ATTENTION message when there is an old swap file
-        * for the current file, and the buffer was not recovered. */
-        if (differ == FALSE && !(curbuf->b_flags & BF_RECOVERED)
-            && vim_strchr(p_shm, SHM_ATTENTION) == NULL) {
-#if defined(HAS_SWAP_EXISTS_ACTION)
-          int choice = 0;
-#endif
-
-#if defined(UNIX) && (defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG))
-          process_still_running = FALSE;
-#endif
-          /*
-           * If there is an SwapExists autocommand and we can handle
-           * the response, trigger it.  It may return 0 to ask the
-           * user anyway.
-           */
-          if (swap_exists_action != SEA_NONE
-              && has_autocmd(EVENT_SWAPEXISTS, buf_fname, buf))
-            choice = do_swapexists(buf, fname);
-
-          if (choice == 0) {
-            /* Show info about the existing swap file. */
-            attention_message(buf, fname);
-
-            /* We don't want a 'q' typed at the more-prompt
-             * interrupt loading a file. */
-            got_int = FALSE;
-          }
-
-          if (swap_exists_action != SEA_NONE && choice == 0) {
-            char_u  *name;
-
-            name = alloc((unsigned)(STRLEN(fname)
-                                    + STRLEN(_("Swap file \""))
-                                    + STRLEN(_("\" already exists!")) + 5));
-            STRCPY(name, _("Swap file \""));
-            home_replace(NULL, fname, name + STRLEN(name),
-                1000, TRUE);
-            STRCAT(name, _("\" already exists!"));
-            choice = do_dialog(VIM_WARNING,
-                (char_u *)_("VIM - ATTENTION"),
-                name == NULL
-                ?  (char_u *)_("Swap file already exists!")
-                : name,
-# if defined(UNIX)
-                process_still_running
-                ? (char_u *)_(
-                    "&Open Read-Only\n&Edit anyway\n&Recover\n&Quit\n&Abort") :
-# endif
-                (char_u *)_(
-                    "&Open Read-Only\n&Edit anyway\n&Recover\n&Delete it\n&Quit\n&Abort"),
-                1, NULL, FALSE);
-
-# if defined(UNIX)
-            if (process_still_running && choice >= 4)
-              choice++;                 /* Skip missing "Delete it" button */
-# endif
-            free(name);
-
-            /* pretend screen didn't scroll, need redraw anyway */
-            msg_scrolled = 0;
-            redraw_all_later(NOT_VALID);
-          }
-
-#if defined(HAS_SWAP_EXISTS_ACTION)
-          if (choice > 0) {
-            switch (choice) {
-            case 1:
-              buf->b_p_ro = TRUE;
-              break;
-            case 2:
-              break;
-            case 3:
-              swap_exists_action = SEA_RECOVER;
-              break;
-            case 4:
-              os_remove((char *)fname);
-              break;
-            case 5:
-              swap_exists_action = SEA_QUIT;
-              break;
-            case 6:
-              swap_exists_action = SEA_QUIT;
-              got_int = TRUE;
-              break;
-            }
-
-            /* If the file was deleted this fname can be used. */
-            if (!os_file_exists(fname))
-              break;
-          } else
-#endif
-          {
-            MSG_PUTS("\n");
-            if (msg_silent == 0)
-              /* call wait_return() later */
-              need_wait_return = TRUE;
-          }
-
-        }
-      }
-    }
-
-    /*
-     * Change the ".swp" extension to find another file that can be used.
-     * First decrement the last char: ".swo", ".swn", etc.
-     * If that still isn't enough decrement the last but one char: ".svz"
-     * Can happen when editing many "No Name" buffers.
-     */
-    if (fname[n - 1] == 'a') {          /* ".s?a" */
-      if (fname[n - 2] == 'a') {        /* ".saa": tried enough, give up */
-        EMSG(_("E326: Too many swap files found"));
-        free(fname);
-        fname = NULL;
-        break;
-      }
-      --fname[n - 2];                   /* ".svz", ".suz", etc. */
-      fname[n - 1] = 'z' + 1;
-    }
-    --fname[n - 1];                     /* ".swo", ".swn", etc. */
-  }
-
-  free(dir_name);
-  return fname;
-}
-
-static int b0_magic_wrong(ZERO_BL *b0p)
-{
-  return b0p->b0_magic_long != (long)B0_MAGIC_LONG
-         || b0p->b0_magic_int != (int)B0_MAGIC_INT
-         || b0p->b0_magic_short != (short)B0_MAGIC_SHORT
-         || b0p->b0_magic_char != B0_MAGIC_CHAR;
-}
-
-#ifdef CHECK_INODE
-/*
- * Compare current file name with file name from swap file.
- * Try to use inode numbers when possible.
- * Return non-zero when files are different.
- *
- * When comparing file names a few things have to be taken into consideration:
- * - When working over a network the full path of a file depends on the host.
- *   We check the inode number if possible.  It is not 100% reliable though,
- *   because the device number cannot be used over a network.
- * - When a file does not exist yet (editing a new file) there is no inode
- *   number.
- * - The file name in a swap file may not be valid on the current host.  The
- *   "~user" form is used whenever possible to avoid this.
- *
- * This is getting complicated, let's make a table:
- *
- *		ino_c  ino_s  fname_c  fname_s	differ =
- *
- * both files exist -> compare inode numbers:
- *		!= 0   != 0	X	 X	ino_c != ino_s
- *
- * inode number(s) unknown, file names available -> compare file names
- *		== 0	X	OK	 OK	fname_c != fname_s
- *		 X     == 0	OK	 OK	fname_c != fname_s
- *
- * current file doesn't exist, file for swap file exist, file name(s) not
- * available -> probably different
- *		== 0   != 0    FAIL	 X	TRUE
- *		== 0   != 0	X	FAIL	TRUE
- *
- * current file exists, inode for swap unknown, file name(s) not
- * available -> probably different
- *		!= 0   == 0    FAIL	 X	TRUE
- *		!= 0   == 0	X	FAIL	TRUE
- *
- * current file doesn't exist, inode for swap unknown, one file name not
- * available -> probably different
- *		== 0   == 0    FAIL	 OK	TRUE
- *		== 0   == 0	OK	FAIL	TRUE
- *
- * current file doesn't exist, inode for swap unknown, both file names not
- * available -> probably same file
- *		== 0   == 0    FAIL	FAIL	FALSE
- *
- * Note that when the ino_t is 64 bits, only the last 32 will be used.  This
- * can't be changed without making the block 0 incompatible with 32 bit
- * versions.
- */
-
-static int 
-fnamecmp_ino (
-    char_u *fname_c,               /* current file name */
-    char_u *fname_s,               /* file name from swap file */
-    long ino_block0
-)
-{
-  ino_t ino_c = 0;                  /* ino of current file */
-  ino_t ino_s;                      /* ino of file from swap file */
-  char_u buf_c[MAXPATHL];           /* full path of fname_c */
-  char_u buf_s[MAXPATHL];           /* full path of fname_s */
-  int retval_c;                     /* flag: buf_c valid */
-  int retval_s;                     /* flag: buf_s valid */
-
-  FileInfo file_info;
-  if (os_get_file_info((char *)fname_c, &file_info)) {
-    ino_c = (ino_t)file_info.stat.st_ino;
-  }
-
-  /*
-   * First we try to get the inode from the file name, because the inode in
-   * the swap file may be outdated.  If that fails (e.g. this path is not
-   * valid on this machine), use the inode from block 0.
-   */
-  if (os_get_file_info((char *)fname_s, &file_info)) {
-    ino_s = (ino_t)file_info.stat.st_ino;
-  } else {
-    ino_s = (ino_t)ino_block0;
-  }
-
-  if (ino_c && ino_s)
-    return ino_c != ino_s;
-
-  /*
-   * One of the inode numbers is unknown, try a forced vim_FullName() and
-   * compare the file names.
-   */
-  retval_c = vim_FullName(fname_c, buf_c, MAXPATHL, TRUE);
-  retval_s = vim_FullName(fname_s, buf_s, MAXPATHL, TRUE);
-  if (retval_c == OK && retval_s == OK)
-    return STRCMP(buf_c, buf_s) != 0;
-
-  /*
-   * Can't compare inodes or file names, guess that the files are different,
-   * unless both appear not to exist at all.
-   */
-  if (ino_s == 0 && ino_c == 0 && retval_c == FAIL && retval_s == FAIL)
-    return FALSE;
-  return TRUE;
-}
-#endif /* CHECK_INODE */
-
-/*
- * Move a long integer into a four byte character array.
- * Used for machine independency in block zero.
- */
-static void long_to_char(long n, char_u *s)
-{
-  s[0] = (char_u)(n & 0xff);
-  n = (unsigned)n >> 8;
-  s[1] = (char_u)(n & 0xff);
-  n = (unsigned)n >> 8;
-  s[2] = (char_u)(n & 0xff);
-  n = (unsigned)n >> 8;
-  s[3] = (char_u)(n & 0xff);
-}
-
-static long char_to_long(char_u *s)
-{
-  long retval;
-
-  retval = s[3];
-  retval <<= 8;
-  retval |= s[2];
-  retval <<= 8;
-  retval |= s[1];
-  retval <<= 8;
-  retval |= s[0];
-
-  return retval;
-}
-
-/*
- * Set the flags in the first block of the swap file:
- * - file is modified or not: buf->b_changed
- * - 'fileformat'
- * - 'fileencoding'
- */
-void ml_setflags(buf_T *buf)
-{
-  bhdr_T      *hp;
-  ZERO_BL     *b0p;
-
-  if (!buf->b_ml.ml_mfp)
-    return;
-  for (hp = buf->b_ml.ml_mfp->mf_used_last; hp != NULL; hp = hp->bh_prev) {
-    if (hp->bh_bnum == 0) {
-      b0p = (ZERO_BL *)(hp->bh_data);
-      b0p->b0_dirty = buf->b_changed ? B0_DIRTY : 0;
-      b0p->b0_flags = (b0p->b0_flags & ~B0_FF_MASK)
-                      | (get_fileformat(buf) + 1);
-      add_b0_fenc(b0p, buf);
-      hp->bh_flags |= BH_DIRTY;
-      mf_sync(buf->b_ml.ml_mfp, MFS_ZERO);
-      break;
-    }
-  }
-}
-
-/*
- * If "data" points to a data block encrypt the text in it and return a copy
- * in allocated memory.
- */
-char_u *ml_encrypt_data(memfile_T *mfp, char_u *data, off_t offset, unsigned size)
-{
-  DATA_BL     *dp = (DATA_BL *)data;
-  char_u      *head_end;
-  char_u      *text_start;
-  char_u      *new_data;
-  int text_len;
-
-  if (dp->db_id != DATA_ID)
-    return data;
-
-  new_data = xmalloc(size);
-  head_end = (char_u *)(&dp->db_index[dp->db_line_count]);
-  text_start = (char_u *)dp + dp->db_txt_start;
-  text_len = size - dp->db_txt_start;
-
-  /* Copy the header and the text. */
-  memmove(new_data, dp, head_end - (char_u *)dp);
-
-  /* Encrypt the text. */
-  crypt_push_state();
-  ml_crypt_prepare(mfp, offset, FALSE);
-  crypt_encode(text_start, text_len, new_data + dp->db_txt_start);
-  crypt_pop_state();
-
-  /* Clear the gap. */
-  if (head_end < text_start)
-    memset(new_data + (head_end - data), 0, text_start - head_end);
-
-  return new_data;
-}
-
-/*
- * Decrypt the text in "data" if it points to a data block.
- */
-void ml_decrypt_data(memfile_T *mfp, char_u *data, off_t offset, unsigned size)
-{
-  DATA_BL     *dp = (DATA_BL *)data;
-  char_u      *head_end;
-  char_u      *text_start;
-  int text_len;
-
-  if (dp->db_id == DATA_ID) {
-    head_end = (char_u *)(&dp->db_index[dp->db_line_count]);
-    text_start = (char_u *)dp + dp->db_txt_start;
-    text_len = dp->db_txt_end - dp->db_txt_start;
-
-    if (head_end > text_start || dp->db_txt_start > size
-        || dp->db_txt_end > size)
-      return;        /* data was messed up */
-
-    /* Decrypt the text in place. */
-    crypt_push_state();
-    ml_crypt_prepare(mfp, offset, TRUE);
-    crypt_decode(text_start, text_len);
-    crypt_pop_state();
-  }
-}
-
-/*
- * Prepare for encryption/decryption, using the key, seed and offset.
- */
-static void ml_crypt_prepare(memfile_T *mfp, off_t offset, int reading)
-{
-  buf_T       *buf = mfp->mf_buffer;
-  char_u salt[50];
-  int method;
-  char_u      *key;
-  char_u      *seed;
-
-  if (reading && mfp->mf_old_key != NULL) {
-    /* Reading back blocks with the previous key/method/seed. */
-    method = mfp->mf_old_cm;
-    key = mfp->mf_old_key;
-    seed = mfp->mf_old_seed;
-  } else {
-    method = get_crypt_method(buf);
-    key = buf->b_p_key;
-    seed = mfp->mf_seed;
-  }
-
-  use_crypt_method = method;    /* select pkzip or blowfish */
-  if (method == 0) {
-    vim_snprintf((char *)salt, sizeof(salt), "%s%" PRId64 "",
-                 key, (int64_t)offset);
-    crypt_init_keys(salt);
-  } else {
-    /* Using blowfish, add salt and seed. We use the byte offset of the
-     * block for the salt. */
-    vim_snprintf((char *)salt, sizeof(salt), "%" PRId64, (int64_t)offset);
-    bf_key_init(key, salt, (int)STRLEN(salt));
-    bf_cfb_init(seed, MF_SEED_LEN);
-  }
-}
-
-
-
-
-#define MLCS_MAXL 800   /* max no of lines in chunk */
-#define MLCS_MINL 400   /* should be half of MLCS_MAXL */
-
-/*
- * Keep information for finding byte offset of a line, updtype may be one of:
- * ML_CHNK_ADDLINE: Add len to parent chunk, possibly splitting it
- *	   Careful: ML_CHNK_ADDLINE may cause ml_find_line() to be called.
- * ML_CHNK_DELLINE: Subtract len from parent chunk, possibly deleting it
- * ML_CHNK_UPDLINE: Add len to parent chunk, as a signed entity.
- */
-static void ml_updatechunk(buf_T *buf, linenr_T line, long len, int updtype)
-{
-  static buf_T        *ml_upd_lastbuf = NULL;
-  static linenr_T ml_upd_lastline;
-  static linenr_T ml_upd_lastcurline;
-  static int ml_upd_lastcurix;
-
-  linenr_T curline = ml_upd_lastcurline;
-  int curix = ml_upd_lastcurix;
-  long size;
-  chunksize_T         *curchnk;
-  int rest;
-  bhdr_T              *hp;
-  DATA_BL             *dp;
-
-  if (buf->b_ml.ml_usedchunks == -1 || len == 0)
-    return;
-  if (buf->b_ml.ml_chunksize == NULL) {
-    buf->b_ml.ml_chunksize = xmalloc(sizeof(chunksize_T) * 100);
-    buf->b_ml.ml_numchunks = 100;
-    buf->b_ml.ml_usedchunks = 1;
-    buf->b_ml.ml_chunksize[0].mlcs_numlines = 1;
-    buf->b_ml.ml_chunksize[0].mlcs_totalsize = 1;
-  }
-
-  if (updtype == ML_CHNK_UPDLINE && buf->b_ml.ml_line_count == 1) {
-    /*
-     * First line in empty buffer from ml_flush_line() -- reset
-     */
-    buf->b_ml.ml_usedchunks = 1;
-    buf->b_ml.ml_chunksize[0].mlcs_numlines = 1;
-    buf->b_ml.ml_chunksize[0].mlcs_totalsize =
-      (long)STRLEN(buf->b_ml.ml_line_ptr) + 1;
-    return;
-  }
-
-  /*
-   * Find chunk that our line belongs to, curline will be at start of the
-   * chunk.
-   */
-  if (buf != ml_upd_lastbuf || line != ml_upd_lastline + 1
-      || updtype != ML_CHNK_ADDLINE) {
-    for (curline = 1, curix = 0;
-         curix < buf->b_ml.ml_usedchunks - 1
-                 && line >= curline +
-                             buf->b_ml.ml_chunksize[curix].mlcs_numlines;
-         curix++) {
-      curline += buf->b_ml.ml_chunksize[curix].mlcs_numlines;
-    }
-  } else if (line >= curline + buf->b_ml.ml_chunksize[curix].mlcs_numlines
-             && curix < buf->b_ml.ml_usedchunks - 1) {
-    /* Adjust cached curix & curline */
-    curline += buf->b_ml.ml_chunksize[curix].mlcs_numlines;
-    curix++;
-  }
-  curchnk = buf->b_ml.ml_chunksize + curix;
-
-  if (updtype == ML_CHNK_DELLINE)
-    len = -len;
-  curchnk->mlcs_totalsize += len;
-  if (updtype == ML_CHNK_ADDLINE) {
-    curchnk->mlcs_numlines++;
-
-    /* May resize here so we don't have to do it in both cases below */
-    if (buf->b_ml.ml_usedchunks + 1 >= buf->b_ml.ml_numchunks) {
-      buf->b_ml.ml_numchunks = buf->b_ml.ml_numchunks * 3 / 2;
-      buf->b_ml.ml_chunksize = (chunksize_T *)
-                               xrealloc(buf->b_ml.ml_chunksize,
-          sizeof(chunksize_T) * buf->b_ml.ml_numchunks);
-    }
-
-    if (buf->b_ml.ml_chunksize[curix].mlcs_numlines >= MLCS_MAXL) {
-      int count;                    /* number of entries in block */
-      int idx;
-      int text_end;
-      int linecnt;
-
-      memmove(buf->b_ml.ml_chunksize + curix + 1,
-          buf->b_ml.ml_chunksize + curix,
-          (buf->b_ml.ml_usedchunks - curix) *
-          sizeof(chunksize_T));
-      /* Compute length of first half of lines in the split chunk */
-      size = 0;
-      linecnt = 0;
-      while (curline < buf->b_ml.ml_line_count
-             && linecnt < MLCS_MINL) {
-        if ((hp = ml_find_line(buf, curline, ML_FIND)) == NULL) {
-          buf->b_ml.ml_usedchunks = -1;
-          return;
-        }
-        dp = (DATA_BL *)(hp->bh_data);
-        count = (long)(buf->b_ml.ml_locked_high) -
-                (long)(buf->b_ml.ml_locked_low) + 1;
-        idx = curline - buf->b_ml.ml_locked_low;
-        curline = buf->b_ml.ml_locked_high + 1;
-        if (idx == 0)        /* first line in block, text at the end */
-          text_end = dp->db_txt_end;
-        else
-          text_end = ((dp->db_index[idx - 1]) & DB_INDEX_MASK);
-        /* Compute index of last line to use in this MEMLINE */
-        rest = count - idx;
-        if (linecnt + rest > MLCS_MINL) {
-          idx += MLCS_MINL - linecnt - 1;
-          linecnt = MLCS_MINL;
-        } else {
-          idx = count - 1;
-          linecnt += rest;
-        }
-        size += text_end - ((dp->db_index[idx]) & DB_INDEX_MASK);
-      }
-      buf->b_ml.ml_chunksize[curix].mlcs_numlines = linecnt;
-      buf->b_ml.ml_chunksize[curix + 1].mlcs_numlines -= linecnt;
-      buf->b_ml.ml_chunksize[curix].mlcs_totalsize = size;
-      buf->b_ml.ml_chunksize[curix + 1].mlcs_totalsize -= size;
-      buf->b_ml.ml_usedchunks++;
-      ml_upd_lastbuf = NULL;         /* Force recalc of curix & curline */
-      return;
-    } else if (buf->b_ml.ml_chunksize[curix].mlcs_numlines >= MLCS_MINL
-               && curix == buf->b_ml.ml_usedchunks - 1
-               && buf->b_ml.ml_line_count - line <= 1) {
-      /*
-       * We are in the last chunk and it is cheap to crate a new one
-       * after this. Do it now to avoid the loop above later on
-       */
-      curchnk = buf->b_ml.ml_chunksize + curix + 1;
-      buf->b_ml.ml_usedchunks++;
-      if (line == buf->b_ml.ml_line_count) {
-        curchnk->mlcs_numlines = 0;
-        curchnk->mlcs_totalsize = 0;
-      } else {
-        /*
-         * Line is just prior to last, move count for last
-         * This is the common case  when loading a new file
-         */
-        hp = ml_find_line(buf, buf->b_ml.ml_line_count, ML_FIND);
-        if (hp == NULL) {
-          buf->b_ml.ml_usedchunks = -1;
-          return;
-        }
-        dp = (DATA_BL *)(hp->bh_data);
-        if (dp->db_line_count == 1)
-          rest = dp->db_txt_end - dp->db_txt_start;
-        else
-          rest =
-            ((dp->db_index[dp->db_line_count - 2]) & DB_INDEX_MASK)
-            - dp->db_txt_start;
-        curchnk->mlcs_totalsize = rest;
-        curchnk->mlcs_numlines = 1;
-        curchnk[-1].mlcs_totalsize -= rest;
-        curchnk[-1].mlcs_numlines -= 1;
-      }
-    }
-  } else if (updtype == ML_CHNK_DELLINE) {
-    curchnk->mlcs_numlines--;
-    ml_upd_lastbuf = NULL;       /* Force recalc of curix & curline */
-    if (curix < (buf->b_ml.ml_usedchunks - 1)
-        && (curchnk->mlcs_numlines + curchnk[1].mlcs_numlines)
-        <= MLCS_MINL) {
-      curix++;
-      curchnk = buf->b_ml.ml_chunksize + curix;
-    } else if (curix == 0 && curchnk->mlcs_numlines <= 0) {
-      buf->b_ml.ml_usedchunks--;
-      memmove(buf->b_ml.ml_chunksize, buf->b_ml.ml_chunksize + 1,
-          buf->b_ml.ml_usedchunks * sizeof(chunksize_T));
-      return;
-    } else if (curix == 0 || (curchnk->mlcs_numlines > 10
-                              && (curchnk->mlcs_numlines +
-                                  curchnk[-1].mlcs_numlines)
-                              > MLCS_MINL)) {
-      return;
-    }
-
-    /* Collapse chunks */
-    curchnk[-1].mlcs_numlines += curchnk->mlcs_numlines;
-    curchnk[-1].mlcs_totalsize += curchnk->mlcs_totalsize;
-    buf->b_ml.ml_usedchunks--;
-    if (curix < buf->b_ml.ml_usedchunks) {
-      memmove(buf->b_ml.ml_chunksize + curix,
-          buf->b_ml.ml_chunksize + curix + 1,
-          (buf->b_ml.ml_usedchunks - curix) *
-          sizeof(chunksize_T));
-    }
-    return;
-  }
-  ml_upd_lastbuf = buf;
-  ml_upd_lastline = line;
-  ml_upd_lastcurline = curline;
-  ml_upd_lastcurix = curix;
-}
-
-/*
- * Find offset for line or line with offset.
- * Find line with offset if "lnum" is 0; return remaining offset in offp
- * Find offset of line if "lnum" > 0
- * return -1 if information is not available
- */
-long ml_find_line_or_offset(buf_T *buf, linenr_T lnum, long *offp)
-{
-  linenr_T curline;
-  int curix;
-  long size;
-  bhdr_T      *hp;
-  DATA_BL     *dp;
-  int count;                    /* number of entries in block */
-  int idx;
-  int start_idx;
-  int text_end;
-  long offset;
-  int len;
-  int ffdos = (get_fileformat(buf) == EOL_DOS);
-  int extra = 0;
-
-  /* take care of cached line first */
-  ml_flush_line(curbuf);
-
-  if (buf->b_ml.ml_usedchunks == -1
-      || buf->b_ml.ml_chunksize == NULL
-      || lnum < 0)
-    return -1;
-
-  if (offp == NULL)
-    offset = 0;
-  else
-    offset = *offp;
-  if (lnum == 0 && offset <= 0)
-    return 1;       /* Not a "find offset" and offset 0 _must_ be in line 1 */
-  /*
-   * Find the last chunk before the one containing our line. Last chunk is
-   * special because it will never qualify
-   */
-  curline = 1;
-  curix = size = 0;
-  while (curix < buf->b_ml.ml_usedchunks - 1
-         && ((lnum != 0
-              && lnum >= curline + buf->b_ml.ml_chunksize[curix].mlcs_numlines)
-             || (offset != 0
-                 && offset > size +
-                 buf->b_ml.ml_chunksize[curix].mlcs_totalsize
-                 + ffdos * buf->b_ml.ml_chunksize[curix].mlcs_numlines))) {
-    curline += buf->b_ml.ml_chunksize[curix].mlcs_numlines;
-    size += buf->b_ml.ml_chunksize[curix].mlcs_totalsize;
-    if (offset && ffdos)
-      size += buf->b_ml.ml_chunksize[curix].mlcs_numlines;
-    curix++;
-  }
-
-  while ((lnum != 0 && curline < lnum) || (offset != 0 && size < offset)) {
-    if (curline > buf->b_ml.ml_line_count
-        || (hp = ml_find_line(buf, curline, ML_FIND)) == NULL)
-      return -1;
-    dp = (DATA_BL *)(hp->bh_data);
-    count = (long)(buf->b_ml.ml_locked_high) -
-            (long)(buf->b_ml.ml_locked_low) + 1;
-    start_idx = idx = curline - buf->b_ml.ml_locked_low;
-    if (idx == 0)    /* first line in block, text at the end */
-      text_end = dp->db_txt_end;
-    else
-      text_end = ((dp->db_index[idx - 1]) & DB_INDEX_MASK);
-    /* Compute index of last line to use in this MEMLINE */
-    if (lnum != 0) {
-      if (curline + (count - idx) >= lnum)
-        idx += lnum - curline - 1;
-      else
-        idx = count - 1;
-    } else {
-      extra = 0;
-      while (offset >= size
-             + text_end - (int)((dp->db_index[idx]) & DB_INDEX_MASK)
-             + ffdos) {
-        if (ffdos)
-          size++;
-        if (idx == count - 1) {
-          extra = 1;
-          break;
-        }
-        idx++;
-      }
-    }
-    len = text_end - ((dp->db_index[idx]) & DB_INDEX_MASK);
-    size += len;
-    if (offset != 0 && size >= offset) {
-      if (size + ffdos == offset)
-        *offp = 0;
-      else if (idx == start_idx)
-        *offp = offset - size + len;
-      else
-        *offp = offset - size + len
-                - (text_end - ((dp->db_index[idx - 1]) & DB_INDEX_MASK));
-      curline += idx - start_idx + extra;
-      if (curline > buf->b_ml.ml_line_count)
-        return -1;              /* exactly one byte beyond the end */
-      return curline;
-    }
-    curline = buf->b_ml.ml_locked_high + 1;
-  }
-
-  if (lnum != 0) {
-    /* Count extra CR characters. */
-    if (ffdos)
-      size += lnum - 1;
-
-    /* Don't count the last line break if 'bin' and 'noeol'. */
-    if (buf->b_p_bin && !buf->b_p_eol)
-      size -= ffdos + 1;
-  }
-
-  return size;
-}
-
-/*
- * Goto byte in buffer with offset 'cnt'.
- */
-void goto_byte(long cnt)
-{
-  long boff = cnt;
-  linenr_T lnum;
-
-  ml_flush_line(curbuf);        /* cached line may be dirty */
-  setpcmark();
-  if (boff)
-    --boff;
-  lnum = ml_find_line_or_offset(curbuf, (linenr_T)0, &boff);
-  if (lnum < 1) {       /* past the end */
-    curwin->w_cursor.lnum = curbuf->b_ml.ml_line_count;
-    curwin->w_curswant = MAXCOL;
-    coladvance((colnr_T)MAXCOL);
-  } else {
-    curwin->w_cursor.lnum = lnum;
-    curwin->w_cursor.col = (colnr_T)boff;
-    curwin->w_cursor.coladd = 0;
-    curwin->w_set_curswant = TRUE;
-  }
-  check_cursor();
-
-  /* Make sure the cursor is on the first byte of a multi-byte char. */
-  if (has_mbyte)
-    mb_adjust_cursor();
-}