Merge pull request #3911 from sethjackson/have-fsync-guard

os_fsync

6 files changed, 46 insertions, 56 deletions

diff --git a/src/nvim/fileio.c b/src/nvim/fileio.c
index 1a6c85abaa..58269983c5 100644
--- a/src/nvim/fileio.c
+++ b/src/nvim/fileio.c
@@ -3368,16 +3368,16 @@ restore_backup:
     nchars += len;
   }
 
-#if defined(UNIX) && defined(HAVE_FSYNC)
-  /* On many journalling file systems there is a bug that causes both the
-   * original and the backup file to be lost when halting the system right
-   * after writing the file.  That's because only the meta-data is
-   * journalled.  Syncing the file slows down the system, but assures it has
-   * been written to disk and we don't lose it.
-   * For a device do try the fsync() but don't complain if it does not work
-   * (could be a pipe).
-   * If the 'fsync' option is FALSE, don't fsync().  Useful for laptops. */
-  if (p_fs && fsync(fd) != 0 && !device) {
+#if defined(UNIX)
+  // On many journalling file systems there is a bug that causes both the
+  // original and the backup file to be lost when halting the system right
+  // after writing the file.  That's because only the meta-data is
+  // journalled.  Syncing the file slows down the system, but assures it has
+  // been written to disk and we don't lose it.
+  // For a device do try the fsync() but don't complain if it does not work
+  // (could be a pipe).
+  // If the 'fsync' option is FALSE, don't fsync().  Useful for laptops.
+  if (p_fs && os_fsync(fd) != 0 && !device) {
     errmsg = (char_u *)_("E667: Fsync failed");
     end = 0;
   }
diff --git a/src/nvim/memfile.c b/src/nvim/memfile.c
index 3df4cbc4a3..9f5e4247b5 100644
--- a/src/nvim/memfile.c
+++ b/src/nvim/memfile.c
@@ -460,31 +460,11 @@ int mf_sync(memfile_T *mfp, int flags)
     mfp->mf_dirty = false;
 
   if ((flags & MFS_FLUSH) && *p_sws != NUL) {
-#if defined(UNIX)
-# ifdef HAVE_FSYNC
     if (STRCMP(p_sws, "fsync") == 0) {
-      if (fsync(mfp->mf_fd))
+      if (os_fsync(mfp->mf_fd)) {
         status = FAIL;
-    } else {
-# endif
-    // OpenNT is strictly POSIX (Benzinger).
-    // Tandem/Himalaya NSK-OSS doesn't have sync()
-# if defined(__OPENNT) || defined(__TANDEM)
-    fflush(NULL);
-# else
-    sync();
-# endif
-# ifdef HAVE_FSYNC
+      }
     }
-# endif
-#endif
-# ifdef SYNC_DUP_CLOSE
-    // Win32 is a bit more work: Duplicate the file handle and close it.
-    // This should flush the file to disk.
-    int fd;
-    if ((fd = dup(mfp->mf_fd)) >= 0)
-      close(fd);
-# endif
   }
 
   got_int |= got_int_save;
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index c72e1cf0bb..938aa9bc83 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -405,27 +405,25 @@ static char *(p_fdo_values[]) = {"all", "block", "hor", "mark", "percent",
 # define FDO_INSERT             0x100
 # define FDO_UNDO               0x200
 # define FDO_JUMP               0x400
-EXTERN char_u   *p_fp;          /* 'formatprg' */
-#ifdef HAVE_FSYNC
-EXTERN int p_fs;                /* 'fsync' */
-#endif
-EXTERN int p_gd;                /* 'gdefault' */
-EXTERN char_u   *p_pdev;        /* 'printdevice' */
-EXTERN char_u   *p_penc;        /* 'printencoding' */
-EXTERN char_u   *p_pexpr;       /* 'printexpr' */
-EXTERN char_u   *p_pmfn;        /* 'printmbfont' */
-EXTERN char_u   *p_pmcs;        /* 'printmbcharset' */
-EXTERN char_u   *p_pfn;         /* 'printfont' */
-EXTERN char_u   *p_popt;        /* 'printoptions' */
-EXTERN char_u   *p_header;      /* 'printheader' */
-EXTERN int p_prompt;            /* 'prompt' */
-EXTERN char_u   *p_guicursor;   /* 'guicursor' */
-EXTERN char_u   *p_hf;          /* 'helpfile' */
-EXTERN long p_hh;               /* 'helpheight' */
-EXTERN char_u   *p_hlg;         /* 'helplang' */
-EXTERN int p_hid;               /* 'hidden' */
-/* Use P_HID to check if a buffer is to be hidden when it is no longer
- * visible in a window. */
+EXTERN char_u   *p_fp;          // 'formatprg'
+EXTERN int p_fs;                // 'fsync'
+EXTERN int p_gd;                // 'gdefault'
+EXTERN char_u   *p_pdev;        // 'printdevice'
+EXTERN char_u   *p_penc;        // 'printencoding'
+EXTERN char_u   *p_pexpr;       // 'printexpr'
+EXTERN char_u   *p_pmfn;        // 'printmbfont'
+EXTERN char_u   *p_pmcs;        // 'printmbcharset'
+EXTERN char_u   *p_pfn;         // 'printfont'
+EXTERN char_u   *p_popt;        // 'printoptions'
+EXTERN char_u   *p_header;      // 'printheader'
+EXTERN int p_prompt;            // 'prompt'
+EXTERN char_u   *p_guicursor;   // 'guicursor'
+EXTERN char_u   *p_hf;          // 'helpfile'
+EXTERN long p_hh;               // 'helpheight'
+EXTERN char_u   *p_hlg;         // 'helplang'
+EXTERN int p_hid;               // 'hidden'
+// Use P_HID to check if a buffer is to be hidden when it is no longer
+// visible in a window.
 # define P_HID(buf) (buf_hide(buf))
 EXTERN char_u   *p_hl;          /* 'highlight' */
 EXTERN int p_hls;               /* 'hlsearch' */
diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index 5187340629..e485b90394 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -959,7 +959,6 @@ return {
       type='bool', scope={'global'},
       secure=true,
       vi_def=true,
-      enable_if='HAVE_FSYNC',
       varname='p_fs',
       defaults={if_true={vi=true}}
     },
diff --git a/src/nvim/os/fs.c b/src/nvim/os/fs.c
index d59b66e773..1a4c3495f2 100644
--- a/src/nvim/os/fs.c
+++ b/src/nvim/os/fs.c
@@ -202,6 +202,19 @@ int os_open(const char* path, int flags, int mode)
   return r;
 }
 
+/// Flushes file modifications to disk.
+///
+/// @param fd the file descriptor of the file to flush to disk.
+///
+/// @return `0` on success, a libuv error code on failure.
+int os_fsync(int fd)
+{
+  uv_fs_t fsync_req;
+  int r = uv_fs_fsync(&fs_loop, &fsync_req, fd, NULL);
+  uv_fs_req_cleanup(&fsync_req);
+  return r;
+}
+
 /// Get stat information for a file.
 ///
 /// @return libuv return code.
diff --git a/src/nvim/shada.c b/src/nvim/shada.c
index 42e514aa95..6a30472a7c 100644
--- a/src/nvim/shada.c
+++ b/src/nvim/shada.c
@@ -761,9 +761,9 @@ static void close_sd_writer(ShaDaWriteDef *const sd_writer)
   FUNC_ATTR_NONNULL_ALL
 {
   const int fd = (int)(intptr_t) sd_writer->cookie;
-  if (fsync(fd) < 0) {
+  if (os_fsync(fd) < 0) {
     emsg2(_(SERR "System error while synchronizing ShaDa file: %s"),
-          strerror(errno));
+          os_strerror(errno));
     errno = 0;
   }
   close_file(fd);