1 files changed, 47 insertions, 64 deletions

diff --git a/src/nvim/fileio.c b/src/nvim/fileio.c
index df9c4928c9..724d754ca7 100644
--- a/src/nvim/fileio.c
+++ b/src/nvim/fileio.c
@@ -27,6 +27,7 @@
 #include "nvim/diff.h"
 #include "nvim/drawscreen.h"
 #include "nvim/edit.h"
+#include "nvim/errors.h"
 #include "nvim/eval.h"
 #include "nvim/ex_cmds_defs.h"
 #include "nvim/ex_eval.h"
@@ -887,10 +888,7 @@ retry:
         // Use buffer >= 64K.  Add linerest to double the size if the
         // line gets very long, to avoid a lot of copying. But don't
         // read more than 1 Mbyte at a time, so we can be interrupted.
-        size = 0x10000 + linerest;
-        if (size > 0x100000) {
-          size = 0x100000;
-        }
+        size = MIN(0x10000 + linerest, 0x100000);
       }
 
       // Protect against the argument of lalloc() going negative.
@@ -2418,7 +2416,7 @@ char *modname(const char *fname, const char *ext, bool prepend_dot)
 
   // the file name has at most BASENAMELEN characters.
   if (strlen(ptr) > BASENAMELEN) {
-    ptr[BASENAMELEN] = '\0';
+    ptr[BASENAMELEN] = NUL;
   }
 
   char *s = ptr + strlen(ptr);
@@ -2656,7 +2654,6 @@ static int rename_with_tmp(const char *const from, const char *const to)
 int vim_rename(const char *from, const char *to)
   FUNC_ATTR_NONNULL_ALL
 {
-  char *errmsg = NULL;
   bool use_tmp_file = false;
 
   // When the names are identical, there is nothing to do.  When they refer
@@ -2700,61 +2697,57 @@ int vim_rename(const char *from, const char *to)
   }
 
   // Rename() failed, try copying the file.
-  int perm = os_getperm(from);
-  // For systems that support ACL: get the ACL from the original file.
-  vim_acl_T acl = os_get_acl(from);
-  int fd_in = os_open(from, O_RDONLY, 0);
-  if (fd_in < 0) {
-    os_free_acl(acl);
+  int ret = vim_copyfile(from, to);
+  if (ret != OK) {
     return -1;
   }
 
-  // Create the new file with same permissions as the original.
-  int fd_out = os_open(to, O_CREAT|O_EXCL|O_WRONLY|O_NOFOLLOW, perm);
-  if (fd_out < 0) {
-    close(fd_in);
-    os_free_acl(acl);
-    return -1;
+  if (os_fileinfo(from, &from_info)) {
+    os_remove(from);
   }
 
-  // Avoid xmalloc() here as vim_rename() is called by buf_write() when nvim
-  // is `preserve_exit()`ing.
-  char *buffer = try_malloc(WRITEBUFSIZE);
-  if (buffer == NULL) {
-    close(fd_out);
-    close(fd_in);
-    os_free_acl(acl);
-    return -1;
-  }
+  return 0;
+}
 
-  int n;
-  while ((n = read_eintr(fd_in, buffer, WRITEBUFSIZE)) > 0) {
-    if (write_eintr(fd_out, buffer, (size_t)n) != n) {
-      errmsg = _("E208: Error writing to \"%s\"");
-      break;
+/// Create the new file with same permissions as the original.
+/// Return FAIL for failure, OK for success.
+int vim_copyfile(const char *from, const char *to)
+{
+  char *errmsg = NULL;
+
+#ifdef HAVE_READLINK
+  FileInfo from_info;
+  if (os_fileinfo_link(from, &from_info) && S_ISLNK(from_info.stat.st_mode)) {
+    int ret = -1;
+
+    char linkbuf[MAXPATHL + 1];
+    ssize_t len = readlink(from, linkbuf, MAXPATHL);
+    if (len > 0) {
+      linkbuf[len] = NUL;
+
+      // Create link
+      ret = symlink(linkbuf, to);
     }
-  }
 
-  xfree(buffer);
-  close(fd_in);
-  if (close(fd_out) < 0) {
-    errmsg = _("E209: Error closing \"%s\"");
-  }
-  if (n < 0) {
-    errmsg = _("E210: Error reading \"%s\"");
-    to = from;
+    return ret == 0 ? OK : FAIL;
   }
-#ifndef UNIX  // For Unix os_open() already set the permission.
-  os_setperm(to, perm);
 #endif
+
+  // For systems that support ACL: get the ACL from the original file.
+  vim_acl_T acl = os_get_acl(from);
+
+  if (os_copy(from, to, UV_FS_COPYFILE_EXCL) != 0) {
+    os_free_acl(acl);
+    return FAIL;
+  }
+
   os_set_acl(to, acl);
   os_free_acl(acl);
   if (errmsg != NULL) {
     semsg(errmsg, to);
-    return -1;
+    return FAIL;
   }
-  os_remove(from);
-  return 0;
+  return OK;
 }
 
 static bool already_warned = false;
@@ -2799,9 +2792,7 @@ int check_timestamps(int focus)
         bufref_T bufref;
         set_bufref(&bufref, buf);
         const int n = buf_check_timestamp(buf);
-        if (didit < n) {
-          didit = n;
-        }
+        didit = MAX(didit, n);
         if (n > 0 && !bufref_valid(&bufref)) {
           // Autocommands have removed the buffer, start at the first one again.
           buf = firstbuf;
@@ -3191,11 +3182,7 @@ void buf_reload(buf_T *buf, int orig_mode, bool reload_options)
 
   // Restore the topline and cursor position and check it (lines may
   // have been removed).
-  if (old_topline > curbuf->b_ml.ml_line_count) {
-    curwin->w_topline = curbuf->b_ml.ml_line_count;
-  } else {
-    curwin->w_topline = old_topline;
-  }
+  curwin->w_topline = MIN(old_topline, curbuf->b_ml.ml_line_count);
   curwin->w_cursor = old_cursor;
   check_cursor(curwin);
   update_topline(curwin);
@@ -3277,18 +3264,12 @@ static void vim_mktempdir(void)
   char tmp[TEMP_FILE_PATH_MAXLEN];
   char path[TEMP_FILE_PATH_MAXLEN];
   char user[40] = { 0 };
-  char appname[40] = { 0 };
 
   os_get_username(user, sizeof(user));
   // Usernames may contain slashes! #19240
   memchrsub(user, '/', '_', sizeof(user));
   memchrsub(user, '\\', '_', sizeof(user));
 
-  // Appname may be a relative path, replace slashes to make it name-like.
-  xstrlcpy(appname, get_appname(), sizeof(appname));
-  memchrsub(appname, '/', '%', sizeof(appname));
-  memchrsub(appname, '\\', '%', sizeof(appname));
-
   // Make sure the umask doesn't remove the executable bit.
   // "repl" has been reported to use "0177".
   mode_t umask_save = umask(0077);
@@ -3296,14 +3277,15 @@ static void vim_mktempdir(void)
     // Expand environment variables, leave room for "/tmp/nvim.<user>/XXXXXX/999999999".
     expand_env((char *)temp_dirs[i], tmp, TEMP_FILE_PATH_MAXLEN - 64);
     if (!os_isdir(tmp)) {
+      if (strequal("$TMPDIR", temp_dirs[i])) {
+        WLOG("$TMPDIR tempdir not a directory (or does not exist): %s", tmp);
+      }
       continue;
     }
 
     // "/tmp/" exists, now try to create "/tmp/nvim.<user>/".
     add_pathsep(tmp);
-
-    xstrlcat(tmp, appname, sizeof(tmp));
-    xstrlcat(tmp, ".", sizeof(tmp));
+    xstrlcat(tmp, "nvim.", sizeof(tmp));
     xstrlcat(tmp, user, sizeof(tmp));
     os_mkdir(tmp, 0700);  // Always create, to avoid a race.
     bool owned = os_file_owned(tmp);
@@ -3329,7 +3311,7 @@ static void vim_mktempdir(void)
 #endif
       // If our "root" tempdir is invalid or fails, proceed without "<user>/".
       // Else user1 could break user2 by creating "/tmp/nvim.user2/".
-      tmp[strlen(tmp) - strlen(user)] = '\0';
+      tmp[strlen(tmp) - strlen(user)] = NUL;
     }
 
     // Now try to create "/tmp/nvim.<user>/XXXXXX".
@@ -3636,6 +3618,7 @@ bool match_file_list(char *list, char *sfname, char *ffname)
 /// @param pat_end     first char after pattern or NULL
 /// @param allow_dirs  Result passed back out in here
 /// @param no_bslash   Don't use a backward slash as pathsep
+///                    (only makes a difference when BACKSLASH_IN_FILENAME in defined)
 ///
 /// @return            NULL on failure.
 char *file_pat_to_reg_pat(const char *pat, const char *pat_end, char *allow_dirs, int no_bslash)