Refactor vim_tempname

- temp_count is uint32_t now instead of long because it supposed to be
  at most 999999999 (comment on line 5227) temporary files. The most
  probably it was a long for compatibility with systems where int is
  16-bit.
- Use "nvim" as prefix for temp folder name instead of "v"
- Remove unused parameter from vim_tempname

src/nvim/diff.c

@@ -661,9 +661,9 @@ void ex_diffupdate(exarg_T *eap)
   }
 
   // We need three temp file names.
-  char_u *tmp_orig = vim_tempname('o');
-  char_u *tmp_new = vim_tempname('n');
-  char_u *tmp_diff = vim_tempname('d');
+  char_u *tmp_orig = vim_tempname();
+  char_u *tmp_new = vim_tempname();
+  char_u *tmp_diff = vim_tempname();
 
   if ((tmp_orig == NULL) || (tmp_new == NULL) || (tmp_diff == NULL)) {
     goto theend;
@@ -852,9 +852,9 @@ void ex_diffpatch(exarg_T *eap)
 #endif  // ifdef UNIX
   // We need two temp file names.
   // Name of original temp file.
-  char_u *tmp_orig = vim_tempname('o');
+  char_u *tmp_orig = vim_tempname();
   // Name of patched temp file.
-  char_u *tmp_new = vim_tempname('n');
+  char_u *tmp_new = vim_tempname();
 
   if ((tmp_orig == NULL) || (tmp_new == NULL)) {
     goto theend;

src/nvim/eval.c

@@ -14030,7 +14030,7 @@ static void f_system(typval_T *argvars, typval_T *rettv)
      * Write the string to a temp file, to be used for input of the shell
      * command.
      */
-    if ((infile = vim_tempname('i')) == NULL) {
+    if ((infile = vim_tempname()) == NULL) {
       EMSG(_(e_notmp));
       goto done;
     }
@@ -14231,22 +14231,8 @@ static void f_taglist(typval_T *argvars, typval_T *rettv)
  */
 static void f_tempname(typval_T *argvars, typval_T *rettv)
 {
-  static int x = 'A';
-
   rettv->v_type = VAR_STRING;
-  rettv->vval.v_string = vim_tempname(x);
-
-  /* Advance 'x' to use A-Z and 0-9, so that there are at least 34 different
-   * names.  Skip 'I' and 'O', they are used for shell redirection. */
-  do {
-    if (x == 'Z')
-      x = '0';
-    else if (x == '9')
-      x = 'A';
-    else {
-      ++x;
-    }
-  } while (x == 'I' || x == 'O');
+  rettv->vval.v_string = vim_tempname();
 }
 
 /*

src/nvim/ex_cmds.c

@@ -1032,8 +1032,8 @@ do_filter (
     curbuf->b_op_start.lnum = line1;
     curbuf->b_op_end.lnum = line2;
     curwin->w_cursor.lnum = line2;
-  } else if ((do_in && (itmp = vim_tempname('i')) == NULL)
-      || (do_out && (otmp = vim_tempname('o')) == NULL)) {
+  } else if ((do_in && (itmp = vim_tempname()) == NULL)
+      || (do_out && (otmp = vim_tempname()) == NULL)) {
     EMSG(_(e_notmp));
     goto filterend;
   }
@@ -1601,7 +1601,7 @@ void write_viminfo(char_u *file, int forceit)
        */
       if (fp_out == NULL) {
         free(tempname);
-        if ((tempname = vim_tempname('o')) != NULL)
+        if ((tempname = vim_tempname()) != NULL)
           fp_out = mch_fopen((char *)tempname, WRITEBIN);
       }
 

src/nvim/fileio.c

@@ -2146,7 +2146,7 @@ readfile_charconvert (
   char_u      *tmpname;
   char_u      *errmsg = NULL;
 
-  tmpname = vim_tempname('r');
+  tmpname = vim_tempname();
   if (tmpname == NULL)
     errmsg = (char_u *)_("Can't find temp file for conversion");
   else {
@@ -3163,7 +3163,7 @@ nobackup:
      * overwrite the original file.
      */
     if (*p_ccv != NUL) {
-      wfname = vim_tempname('w');
+      wfname = vim_tempname();
       if (wfname == NULL) {             /* Can't write without a tempfile! */
         errmsg = (char_u *)_("E214: Can't find temp file for writing");
         goto restore_backup;
@@ -5156,7 +5156,7 @@ void write_lnum_adjust(linenr_T offset)
     curbuf->b_no_eol_lnum += offset;
 }
 
-static long temp_count = 0;             /* Temp filename counter. */
+static uint32_t temp_count = 0;             /* Temp filename counter. */
 
 /*
  * Delete the temp directory and all files it contains.
@@ -5208,10 +5208,7 @@ static void vim_settempdir(char_u *tempdir)
  * The returned pointer is to allocated memory.
  * The returned pointer is NULL if no valid name was found.
  */
-char_u *
-vim_tempname (
-    int extra_char          /* char to use in the name instead of '?' */
-)
+char_u *vim_tempname(void)
 {
   char_u itmp[TEMP_FILE_PATH_MAXLEN];
 
@@ -5230,13 +5227,13 @@ vim_tempname (
      * Try the entries in `TEMP_DIR_NAMES` to create the temp directory.
      */
     for (i = 0; i < (int)(sizeof(temp_dirs) / sizeof(char *)); ++i) {
-      /* expand $TMP, leave room for "/v1100000/999999999" */
-      expand_env((char_u *)temp_dirs[i], itmp, TEMP_FILE_PATH_MAXLEN - 20);
+      /* expand $TMP, leave room for "/nvimXXXXXX/999999999" */
+      expand_env((char_u *)temp_dirs[i], itmp, TEMP_FILE_PATH_MAXLEN - 22);
       if (os_isdir(itmp)) {                    /* directory exists */
         add_pathsep(itmp);
 
         /* Leave room for filename */
-        STRCAT(itmp, "vXXXXXX");
+        STRCAT(itmp, "nvimXXXXXX");
         if (os_mkdtemp((char *)itmp) != NULL)
           vim_settempdir(itmp);
         if (vim_tempdir != NULL)
@@ -5248,7 +5245,7 @@ vim_tempname (
   if (vim_tempdir != NULL) {
     /* There is no need to check if the file exists, because we own the
      * directory and nobody else creates a file in it. */
-    sprintf((char *)itmp, "%s%" PRId64, vim_tempdir, (int64_t)temp_count++);
+    sprintf((char *)itmp, "%s%" PRIu32, vim_tempdir, temp_count++);
     return vim_strsave(itmp);
   }
 

src/nvim/hardcopy.c

@@ -2346,7 +2346,7 @@ int mch_print_init(prt_settings_T *psettings, char_u *jobname, int forceit)
 
   /* If the user didn't specify a file name, use a temp file. */
   if (psettings->outfile == NULL) {
-    prt_ps_file_name = vim_tempname('p');
+    prt_ps_file_name = vim_tempname();
     if (prt_ps_file_name == NULL) {
       EMSG(_(e_notmp));
       return FAIL;

src/nvim/if_cscope.c

@@ -1044,7 +1044,7 @@ static int cs_find_common(char *opt, char *pat, int forceit, int verbose, int us
   if (qfpos != NULL && *qfpos != '0' && totmatches > 0) {
     /* fill error list */
     FILE        *f;
-    char_u      *tmp = vim_tempname('c');
+    char_u      *tmp = vim_tempname();
     qf_info_T   *qi = NULL;
     win_T       *wp = NULL;
 

src/nvim/memline.c

@@ -490,7 +490,7 @@ void ml_open_file(buf_T *buf)
 
   /* For a spell buffer use a temp file name. */
   if (buf->b_spell) {
-    fname = vim_tempname('s');
+    fname = vim_tempname();
     if (fname != NULL)
       (void)mf_open_file(mfp, fname);           /* consumes fname! */
     buf->b_may_swap = FALSE;

src/nvim/misc1.c

@@ -3423,7 +3423,7 @@ get_cmd_output (
     return NULL;
 
   /* get a name for the temp file */
-  if ((tempname = vim_tempname('o')) == NULL) {
+  if ((tempname = vim_tempname()) == NULL) {
     EMSG(_(e_notmp));
     return NULL;
   }

src/nvim/os/server.c

@@ -52,7 +52,7 @@ void server_init(void)
   servers = pmap_new(cstr_t)();
 
   if (!os_getenv("NEOVIM_LISTEN_ADDRESS")) {
-    char *listen_address = (char *)vim_tempname('s');
+    char *listen_address = (char *)vim_tempname();
     os_setenv("NEOVIM_LISTEN_ADDRESS", listen_address, 1);
     free(listen_address);
   }

src/nvim/os_unix.c

@@ -1034,7 +1034,7 @@ int mch_expand_wildcards(int num_pat, char_u **pat, int *num_file,
   /*
    * get a name for the temp file
    */
-  if ((tempname = vim_tempname('o')) == NULL) {
+  if ((tempname = vim_tempname()) == NULL) {
     EMSG(_(e_notmp));
     return FAIL;
   }

src/nvim/quickfix.c

@@ -2537,7 +2537,7 @@ static char_u *get_mef_name(void)
   static int off = 0;
 
   if (*p_mef == NUL) {
-    name = vim_tempname('e');
+    name = vim_tempname();
     if (name == NULL)
       EMSG(_(e_notmp));
     return name;

src/nvim/spell.c

@@ -7814,7 +7814,7 @@ spell_add_word (
 
   if (idx == 0) {           // use internal wordlist
     if (int_wordlist == NULL) {
-      int_wordlist = vim_tempname('s');
+      int_wordlist = vim_tempname();
       if (int_wordlist == NULL)
         return;
     }