tweaks: use memory on the stack instead of calling malloc() and free()

Rename some variables in the process, and remove two cluttering asserts.

src/nano.c

@@ -1812,7 +1812,7 @@ int do_mouse(void)
  * TRUE. */
 void do_output(char *output, size_t output_len, bool allow_cntrls)
 {
-    char *char_buf = charalloc(mb_cur_max());
+    char onechar[mb_cur_max()];
     int char_len;
     size_t current_len = strlen(openfile->current->data);
     size_t i = 0;
@@ -1832,7 +1832,7 @@ void do_output(char *output, size_t output_len, bool allow_cntrls)
 	    output[i] = '\n';
 
 	/* Get the next multibyte character. */
-	char_len = parse_mbchar(output + i, char_buf, NULL);
+	char_len = parse_mbchar(output + i, onechar, NULL);
 
 	i += char_len;
 
@@ -1853,7 +1853,7 @@ void do_output(char *output, size_t output_len, bool allow_cntrls)
 	charmove(openfile->current->data + openfile->current_x + char_len,
 			openfile->current->data + openfile->current_x,
 			current_len - openfile->current_x + 1);
-	strncpy(openfile->current->data + openfile->current_x, char_buf,
+	strncpy(openfile->current->data + openfile->current_x, onechar,
 			char_len);
 	current_len += char_len;
 	openfile->totsize++;
@@ -1893,8 +1893,6 @@ void do_output(char *output, size_t output_len, bool allow_cntrls)
 	refresh_needed = TRUE;
 #endif
 
-    free(char_buf);
-
     openfile->placewewant = xplustabs();
 
 #ifndef DISABLE_COLOR

src/prompt.c

@@ -197,7 +197,7 @@ void do_statusbar_output(int *the_input, size_t input_len,
 	bool filtering)
 {
     char *output = charalloc(input_len + 1);
-    char *char_buf = charalloc(mb_cur_max());
+    char onechar[mb_cur_max()];
     int i, char_len;
 
     /* Copy the typed stuff so it can be treated. */
@@ -213,7 +213,7 @@ void do_statusbar_output(int *the_input, size_t input_len,
 	    output[i] = '\n';
 
 	/* Interpret the next multibyte character. */
-	char_len = parse_mbchar(output + i, char_buf, NULL);
+	char_len = parse_mbchar(output + i, onechar, NULL);
 
 	i += char_len;
 
@@ -225,12 +225,11 @@ void do_statusbar_output(int *the_input, size_t input_len,
 	answer = charealloc(answer, strlen(answer) + char_len + 1);
 	charmove(answer + statusbar_x + char_len, answer + statusbar_x,
 				strlen(answer) - statusbar_x + 1);
-	strncpy(answer + statusbar_x, char_buf, char_len);
+	strncpy(answer + statusbar_x, onechar, char_len);
 
 	statusbar_x += char_len;
     }
 
-    free(char_buf);
     free(output);
 
     update_the_statusbar();

src/text.c

@@ -1682,25 +1682,19 @@ ssize_t break_line(const char *line, ssize_t goal, bool snap_at_nl)
 size_t indent_length(const char *line)
 {
     size_t len = 0;
-    char *blank_mb;
-    int blank_mb_len;
-
-    assert(line != NULL);
-
-    blank_mb = charalloc(mb_cur_max());
+    char onechar[mb_cur_max()];
+    int charlen;
 
     while (*line != '\0') {
-	blank_mb_len = parse_mbchar(line, blank_mb, NULL);
+	charlen = parse_mbchar(line, onechar, NULL);
 
-	if (!is_blank_mbchar(blank_mb))
+	if (!is_blank_mbchar(onechar))
 	    break;
 
-	line += blank_mb_len;
-	len += blank_mb_len;
+	line += charlen;
+	len += charlen;
     }
 
-    free(blank_mb);
-
     return len;
 }
 #endif /* !NANO_TINY || !DISABLE_JUSTIFY */