replaced some mch_stat() with os_file_exists()

src/ex_cmds.c

@@ -1492,7 +1492,6 @@ void write_viminfo(char_u *file, int forceit)
   FILE        *fp_in = NULL;    /* input viminfo file, if any */
   FILE        *fp_out = NULL;   /* output viminfo file */
   char_u      *tempname = NULL;         /* name of temp viminfo file */
-  struct stat st_new;           /* mch_stat() of potential new file */
   char_u      *wp;
 #if defined(UNIX)
   mode_t umask_save;
@@ -1511,7 +1510,7 @@ void write_viminfo(char_u *file, int forceit)
   fp_in = mch_fopen((char *)fname, READBIN);
   if (fp_in == NULL) {
     /* if it does exist, but we can't read it, don't try writing */
-    if (mch_stat((char *)fname, &st_new) == 0)
+    if (os_file_exists(fname))
       goto end;
 #if defined(UNIX)
     /*
@@ -1563,7 +1562,7 @@ void write_viminfo(char_u *file, int forceit)
        * Check if tempfile already exists.  Never overwrite an
        * existing file!
        */
-      if (mch_stat((char *)tempname, &st_new) == 0) {
+      if (os_file_exists(tempname)) {
         /*
          * Try another name.  Change one character, just before
          * the extension.
@@ -1571,8 +1570,7 @@ void write_viminfo(char_u *file, int forceit)
         wp = tempname + STRLEN(tempname) - 5;
         if (wp < path_tail(tempname))                 /* empty file name? */
           wp = path_tail(tempname);
-        for (*wp = 'z'; mch_stat((char *)tempname, &st_new) == 0;
-             --*wp) {
+        for (*wp = 'z'; os_file_exists(tempname); --*wp) {
           /*
            * They all exist?  Must be something wrong! Don't
            * write the viminfo file then.

src/fileio.c

@@ -3444,8 +3444,6 @@ nobackup:
 
 restore_backup:
     {
-      struct stat st;
-
       /*
        * If we failed to open the file, we don't need a backup. Throw it
        * away.  If we moved or removed the original file try to put the
@@ -3460,11 +3458,13 @@ restore_backup:
            * In that case we leave the copy around.
            */
           /* If file does not exist, put the copy in its place */
-          if (mch_stat((char *)fname, &st) < 0)
+          if (!os_file_exists(fname)) {
             vim_rename(backup, fname);
+          }
           /* if original file does exist throw away the copy */
-          if (mch_stat((char *)fname, &st) >= 0)
+          if (os_file_exists(fname)) {
             os_remove((char *)backup);
+          }
         } else {
           /* try to put the original file back */
           vim_rename(backup, fname);
@@ -3472,9 +3472,10 @@ restore_backup:
       }
 
       /* if original file no longer exists give an extra warning */
-      if (!newfile && mch_stat((char *)fname, &st) < 0)
+      if (!newfile && !os_file_exists(fname)) {
         end = 0;
       }
+    }
 
     if (wfname != fname)
       free(wfname);
@@ -3855,15 +3856,13 @@ restore_backup:
     char *org = (char *)modname(fname, p_pm, FALSE);
 
     if (backup != NULL) {
-      struct stat st;
-
       /*
        * If the original file does not exist yet
        * the current backup file becomes the original file
        */
       if (org == NULL)
         EMSG(_("E205: Patchmode: can't save original file"));
-      else if (mch_stat(org, &st) < 0) {
+      else if (!os_file_exists((char_u *)org)) {
         vim_rename(backup, (char_u *)org);
         free(backup);                   /* don't delete the file */
         backup = NULL;
@@ -5527,9 +5526,6 @@ vim_tempname (
 #ifdef TEMPDIRNAMES
   static char *(tempdirs[]) = {TEMPDIRNAMES};
   int i;
-# ifndef EEXIST
-  struct stat st;
-# endif
 
   /*
    * This will create a directory for private use by this instance of Vim.
@@ -5580,7 +5576,7 @@ vim_tempname (
           /* If mkdir() does not set errno to EEXIST, check for
            * existing file here.  There is a race condition then,
            * although it's fail-safe. */
-          if (mch_stat((char *)itmp, &st) >= 0)
+          if (os_file_exists(itmp))
             continue;
 #  endif
 #  if defined(UNIX)

src/memline.c

@@ -1607,12 +1607,9 @@ recover_names (
      * Try finding a swap file by simply adding ".swp" to the file name.
      */
     if (*dirp == NUL && file_count + num_files == 0 && fname != NULL) {
-      struct stat st;
-      char_u          *swapname;
-
-      swapname = modname(fname_res, (char_u *)".swp", TRUE);
+      char_u *swapname = modname(fname_res, (char_u *)".swp", TRUE);
       if (swapname != NULL) {
-        if (mch_stat((char *)swapname, &st) != -1) {                /* It exists! */
+        if (os_file_exists(swapname)) {
           files = (char_u **)alloc((unsigned)sizeof(char_u *));
           files[0] = swapname;
           swapname = NULL;

src/spell.c

@@ -7768,7 +7768,6 @@ mkspell (
   afffile_T   *(afile[8]);
   int i;
   int len;
-  struct stat st;
   int error = FALSE;
   spellinfo_T spin;
 
@@ -7832,7 +7831,7 @@ mkspell (
   else {
     // Check for overwriting before doing things that may take a lot of
     // time.
-    if (!over_write && mch_stat((char *)wfname, &st) >= 0) {
+    if (!over_write && os_file_exists(wfname)) {
       EMSG(_(e_exists));
       goto theend;
     }
@@ -7888,7 +7887,7 @@ mkspell (
       spin.si_region = 1 << i;
 
       vim_snprintf((char *)fname, MAXPATHL, "%s.aff", innames[i]);
-      if (mch_stat((char *)fname, &st) >= 0) {
+      if (os_file_exists(fname)) {
         // Read the .aff file.  Will init "spin->si_conv" based on the
         // "SET" line.
         afile[i] = spell_read_aff(&spin, fname);

src/undo.c

@@ -675,7 +675,6 @@ char_u *u_get_undo_file_name(char_u *buf_ffname, int reading)
   char_u      *undo_file_name = NULL;
   int dir_len;
   char_u      *p;
-  struct stat st;
   char_u      *ffname = buf_ffname;
 #ifdef HAVE_READLINK
   char_u fname_buf[MAXPATHL];
@@ -723,7 +722,7 @@ char_u *u_get_undo_file_name(char_u *buf_ffname, int reading)
 
     // When reading check if the file exists.
     if (undo_file_name != NULL &&
-        (!reading || mch_stat((char *)undo_file_name, &st) >= 0)) {
+        (!reading || os_file_exists(undo_file_name))) {
       break;
     }
     free(undo_file_name);
@@ -1108,7 +1107,6 @@ void u_write_undo(char_u *name, int forceit, buf_T *buf, char_u *hash)
   int perm;
   int write_ok = FALSE;
 #ifdef UNIX
-  int st_old_valid = FALSE;
   struct stat st_old;
   struct stat st_new;
 #endif
@@ -1135,16 +1133,10 @@ void u_write_undo(char_u *name, int forceit, buf_T *buf, char_u *hash)
    */
   perm = 0600;
   if (buf->b_ffname != NULL) {
-#ifdef UNIX
-    if (mch_stat((char *)buf->b_ffname, &st_old) >= 0) {
-      perm = st_old.st_mode;
-      st_old_valid = TRUE;
-    }
-#else
     perm = os_getperm(buf->b_ffname);
-    if (perm < 0)
+    if (perm < 0) {
       perm = 0600;
-#endif
+    }
   }
 
   /* strip any s-bit */
@@ -1223,7 +1215,7 @@ void u_write_undo(char_u *name, int forceit, buf_T *buf, char_u *hash)
    * this fails, set the protection bits for the group same as the
    * protection bits for others.
    */
-  if (st_old_valid
+  if (mch_stat((char *)buf->b_ffname, &st_old) >= 0
       && mch_stat((char *)file_name, &st_new) >= 0
       && st_new.st_gid != st_old.st_gid
 # ifdef HAVE_FCHOWN  /* sequent-ptx lacks fchown() */