Limiting the number of backup files to one hundred thousand, well

before finding a unused filename takes an annoying amount of time.


git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@5225 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

ChangeLog

@@ -2,6 +2,10 @@
 	* src/browser.c (browser_refresh): Take the distant possibility of
 	terabyte files into account, and in the bargain get rid of the need
 	to calculate the number of digits in UINT_MAX.
+	* src/files.c (get_next_filename): Limit the number of backup files
+	to one hundred thousand -- which should be far more than enough --
+	before finding a unused filename takes an annoying amount of time.
+	* src/utils.c (digits): Delete this now unneeded function.
 
 2015-05-03  Benno Schulenberg  <bensberg@justemail.net>
 	* src/browser.c (browser_refresh): Display an ellipsis only when the

src/files.c

@@ -991,20 +991,17 @@ int open_file(const char *filename, bool newfie, bool quiet, FILE **f)
  * extension exists, we return "". */
 char *get_next_filename(const char *name, const char *suffix)
 {
-    static int ulmax_digits = -1;
     unsigned long i = 0;
     char *buf;
-    size_t namelen, suffixlen;
+    size_t wholenamelen;
 
     assert(name != NULL && suffix != NULL);
 
-    if (ulmax_digits == -1)
-	ulmax_digits = digits(ULONG_MAX);
+    wholenamelen = strlen(name) + strlen(suffix);
 
-    namelen = strlen(name);
-    suffixlen = strlen(suffix);
-
-    buf = charalloc(namelen + suffixlen + ulmax_digits + 2);
+    /* Reserve space for: the name plus the suffix plus a dot plus
+     * possibly five digits plus a null byte. */
+    buf = charalloc(wholenamelen + 7);
     sprintf(buf, "%s%s", name, suffix);
 
     while (TRUE) {
@@ -1012,11 +1009,12 @@ char *get_next_filename(const char *name, const char *suffix)
 
 	if (stat(buf, &fs) == -1)
 	    return buf;
-	if (i == ULONG_MAX)
+
+	/* Limit the number of backup files to a hundred thousand. */
+	if (++i == 100000)
 	    break;
 
-	i++;
-	sprintf(buf + namelen + suffixlen, ".%lu", i);
+	sprintf(buf + wholenamelen, ".%lu", i);
     }
 
     /* We get here only if there is no possible save file.  Blank out

src/proto.h

@@ -695,7 +695,6 @@ void do_wordlinechar_count(void);
 void do_verbatim_input(void);
 
 /* All functions in utils.c. */
-int digits(size_t n);
 void get_homedir(void);
 bool parse_num(const char *str, ssize_t *val);
 bool parse_line_column(const char *str, ssize_t *line, ssize_t *column);

src/utils.c

@@ -30,21 +30,6 @@
 #include <ctype.h>
 #include <errno.h>
 
-/* Return the number of decimal digits in n. */
-int digits(size_t n)
-{
-    int i;
-
-    if (n == 0)
-	i = 1;
-    else {
-	for (i = 0; n != 0; n /= 10, i++)
-	    ;
-    }
-
-    return i;
-}
-
 /* Return the user's home directory.  We use $HOME, and if that fails,
  * we fall back on the home directory of the effective user ID. */
 void get_homedir(void)