ops: refactor get_spec_reg()

Return value is bool.
errmsg (param) is bool in here and in getaltfname().
allocated (param) is bool.

src/nvim/buffer.c

@@ -2659,9 +2659,8 @@ buf_T *setaltfname(char_u *ffname, char_u *sfname, linenr_T lnum)
  * Get alternate file name for current window.
  * Return NULL if there isn't any, and give error message if requested.
  */
-char_u *
+char_u * getaltfname(
-getaltfname (
+    bool errmsg                   // give error message
-    int errmsg                     /* give error message */
 )
 {
   char_u      *fname;

src/nvim/ex_getln.c

@@ -3286,10 +3286,9 @@ void restore_cmdline_alloc(char_u *p)
 /// @returns FAIL for failure, OK otherwise
 static bool cmdline_paste(int regname, bool literally, bool remcr)
 {
-  long i;
   char_u              *arg;
   char_u              *p;
-  int allocated;
+  bool allocated;
   struct cmdline_info save_ccline;
 
   /* check for valid regname; also accept special characters for CTRL-R in
@@ -3311,7 +3310,7 @@ static bool cmdline_paste(int regname, bool literally, bool remcr)
    * things like going to another buffer when evaluating an expression. */
   save_cmdline(&save_ccline);
   ++textlock;
-  i = get_spec_reg(regname, &arg, &allocated, TRUE);
+  const bool i = get_spec_reg(regname, &arg, &allocated, true);
   --textlock;
   restore_cmdline(&save_ccline);
 

src/nvim/ops.c

@@ -1110,7 +1110,7 @@ int insert_reg(
 )
 {
   int retval = OK;
-  int allocated;
+  bool allocated;
 
   /*
    * It is possible to get into an endless loop by having CTRL-R a in
@@ -1187,75 +1187,75 @@ static void stuffescaped(const char *arg, int literally)
   }
 }
 
-/*
+// If "regname" is a special register, return true and store a pointer to its
- * If "regname" is a special register, return TRUE and store a pointer to its
+// value in "argp".
- * value in "argp".
+bool get_spec_reg(
- */
-int get_spec_reg(
     int regname,
     char_u **argp,
-    int *allocated,         /* return: TRUE when value was allocated */
+    bool *allocated,        // return: true when value was allocated
-    int errmsg                     /* give error message when failing */
+    bool errmsg             // give error message when failing
 )
 {
   size_t cnt;
 
   *argp = NULL;
-  *allocated = FALSE;
+  *allocated = false;
   switch (regname) {
   case '%':                     /* file name */
     if (errmsg)
       check_fname();            /* will give emsg if not set */
     *argp = curbuf->b_fname;
-    return TRUE;
+    return true;
 
   case '#':                     /* alternate file name */
     *argp = getaltfname(errmsg);                /* may give emsg if not set */
-    return TRUE;
+    return true;
 
   case '=':                     /* result of expression */
     *argp = get_expr_line();
-    *allocated = TRUE;
+    *allocated = true;
-    return TRUE;
+    return true;
 
   case ':':                     /* last command line */
     if (last_cmdline == NULL && errmsg)
       EMSG(_(e_nolastcmd));
     *argp = last_cmdline;
-    return TRUE;
+    return true;
 
   case '/':                     /* last search-pattern */
     if (last_search_pat() == NULL && errmsg)
       EMSG(_(e_noprevre));
     *argp = last_search_pat();
-    return TRUE;
+    return true;
 
   case '.':                     /* last inserted text */
     *argp = get_last_insert_save();
-    *allocated = TRUE;
+    *allocated = true;
     if (*argp == NULL && errmsg)
       EMSG(_(e_noinstext));
-    return TRUE;
+    return true;
 
   case Ctrl_F:                  /* Filename under cursor */
   case Ctrl_P:                  /* Path under cursor, expand via "path" */
-    if (!errmsg)
+    if (!errmsg) {
-      return FALSE;
+      return false;
+    }
     *argp = file_name_at_cursor(FNAME_MESS | FNAME_HYP
         | (regname == Ctrl_P ? FNAME_EXP : 0), 1L, NULL);
-    *allocated = TRUE;
+    *allocated = true;
-    return TRUE;
+    return true;
 
   case Ctrl_W:                  /* word under cursor */
   case Ctrl_A:                  /* WORD (mnemonic All) under cursor */
-    if (!errmsg)
+    if (!errmsg) {
-      return FALSE;
+      return false;
+    }
     cnt = find_ident_under_cursor(argp, (regname == Ctrl_W
                                          ? (FIND_IDENT|FIND_STRING)
                                          : FIND_STRING));
     *argp = cnt ? vim_strnsave(*argp, cnt) : NULL;
-    *allocated = TRUE;
+    *allocated = true;
-    return TRUE;
+    return true;
 
   case Ctrl_L:                  // Line under cursor
     if (!errmsg) {
@@ -1267,10 +1267,10 @@ int get_spec_reg(
 
   case '_':                     /* black hole: always empty */
     *argp = (char_u *)"";
-    return TRUE;
+    return true;
   }
 
-  return FALSE;
+  return false;
 }
 
 /// Paste a yank register into the command line.
@@ -2660,7 +2660,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
   int lendiff = 0;
   pos_T old_pos;
   char_u      *insert_string = NULL;
-  int allocated = FALSE;
+  bool allocated = false;
   long cnt;
 
   if (flags & PUT_FIXINDENT)
@@ -2756,7 +2756,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
    * For special registers '%' (file name), '#' (alternate file name) and
    * ':' (last command line), etc. we have to create a fake yank register.
    */
-  if (get_spec_reg(regname, &insert_string, &allocated, TRUE)) {
+  if (get_spec_reg(regname, &insert_string, &allocated, true)) {
     if (insert_string == NULL)
       return;
   }
@@ -4915,8 +4915,8 @@ void *get_reg_contents(int regname, int flags)
     return NULL;
 
   char_u *retval;
-  int allocated;
+  bool allocated;
-  if (get_spec_reg(regname, &retval, &allocated, FALSE)) {
+  if (get_spec_reg(regname, &retval, &allocated, false)) {
     if (retval == NULL)
       return NULL;
     if (allocated) {