* xdisp.c (message_log_check_duplicate): Return unsigned long, not int.

This is less likely to overflow, and avoids undefined behavior if
overflow does occur.  All callers changed.  Use strtoul to scan
for the unsigned long integer.

2 files changed, 13 insertions, 9 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index d491d089514..a9f3e3a5b70 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,10 @@
 2011-03-22  Paul Eggert  <eggert@cs.ucla.edu>
 
+        * xdisp.c (message_log_check_duplicate): Return unsigned long, not int.
+        This is less likely to overflow, and avoids undefined behavior if
+        overflow does occur.  All callers changed.  Use strtoul to scan
+        for the unsigned long integer.
+
         * scroll.c (do_scrolling): Work around GCC bug 48228.
         See <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48228>.
 
diff --git a/src/xdisp.c b/src/xdisp.c
index a7955f41e0c..93bc8c9479e 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -802,8 +802,8 @@ static int cursor_row_fully_visible_p (struct window *, int, int);
 static int try_scrolling (Lisp_Object, int, EMACS_INT, EMACS_INT, int, int);
 static int try_cursor_movement (Lisp_Object, struct text_pos, int *);
 static int trailing_whitespace_p (EMACS_INT);
-static int message_log_check_duplicate (EMACS_INT, EMACS_INT,
-                                        EMACS_INT, EMACS_INT);
+static unsigned long int message_log_check_duplicate (EMACS_INT, EMACS_INT,
+                                                      EMACS_INT, EMACS_INT);
 static void push_it (struct it *);
 static void pop_it (struct it *);
 static void sync_frame_with_window_matrix_rows (struct window *);
@@ -7973,7 +7973,7 @@ message_dolog (const char *m, EMACS_INT nbytes, int nlflag, int multibyte)
       if (nlflag)
         {
           EMACS_INT this_bol, this_bol_byte, prev_bol, prev_bol_byte;
-          int dups;
+          unsigned long int dups;
           insert_1 ("\n", 1, 1, 0, 0);
 
           scan_newline (Z, Z_BYTE, BEG, BEG_BYTE, -2, 0);
@@ -8001,7 +8001,7 @@ message_dolog (const char *m, EMACS_INT nbytes, int nlflag, int multibyte)
 
                       /* If you change this format, don't forget to also
                          change message_log_check_duplicate.  */
-                      sprintf (dupstr, " [%d times]", dups);
+                      sprintf (dupstr, " [%lu times]", dups);
                       duplen = strlen (dupstr);
                       TEMP_SET_PT_BOTH (Z - 1, Z_BYTE - 1);
                       insert_1 (dupstr, duplen, 1, 0, 1);
@@ -8063,7 +8063,7 @@ message_dolog (const char *m, EMACS_INT nbytes, int nlflag, int multibyte)
    Return 0 if different, 1 if the new one should just replace it, or a
    value N > 1 if we should also append " [N times]".  */
 
-static int
+static unsigned long int
 message_log_check_duplicate (EMACS_INT prev_bol, EMACS_INT prev_bol_byte,
                              EMACS_INT this_bol, EMACS_INT this_bol_byte)
 {
@@ -8085,10 +8085,9 @@ message_log_check_duplicate (EMACS_INT prev_bol, EMACS_INT prev_bol_byte,
     return 2;
   if (*p1++ == ' ' && *p1++ == '[')
     {
-      int n = 0;
-      while (*p1 >= '0' && *p1 <= '9')
-        n = n * 10 + *p1++ - '0';
-      if (strncmp ((char *) p1, " times]\n", 8) == 0)
+      char *pend;
+      unsigned long int n = strtoul ((char *) p1, &pend, 10);
+      if (strncmp (pend, " times]\n", 8) == 0)
         return n+1;
     }
   return 0;