[Emacs-diffs] trunk r117502: * coding.c (ALLOC_CONVERSION_WORK_AREA): Prefer ptrdiff_t to int and

[Dmitry Antipov]

------------------------------------------------------------
revno: 117502
revision-id: address@hidden
parent: address@hidden
committer: Dmitry Antipov <address@hidden>
branch nick: trunk
timestamp: Wed 2014-07-09 14:36:35 +0400
message:
  * coding.c (ALLOC_CONVERSION_WORK_AREA): Prefer ptrdiff_t to int and
  so avoid integer overflow if decoded gap size exceeds INT_MAX bytes.
modified:
  src/ChangeLog                  changelog-20091113204419-o5vbwnq5f7feedwu-1438
  src/coding.c                   coding.c-20091113204419-o5vbwnq5f7feedwu-1077

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2014-07-09 06:25:35 +0000
+++ b/src/ChangeLog     2014-07-09 10:36:35 +0000
@@ -15,6 +15,9 @@
        * xfont.c (xfont_open):
        * xftfont.c (xftfont_open): All users changed.
 
+       * coding.c (ALLOC_CONVERSION_WORK_AREA): Prefer ptrdiff_t to int and
+       so avoid integer overflow if decoded gap size exceeds INT_MAX bytes.
+
 2014-07-09  Eli Zaretskii  <address@hidden>
 
        * xdisp.c (move_it_to): Adjust calculation of line_start_x to what

=== modified file 'src/coding.c'
--- a/src/coding.c      2014-07-01 15:34:58 +0000
+++ b/src/coding.c      2014-07-09 10:36:35 +0000
@@ -7273,15 +7273,12 @@
 
 #define ALLOC_CONVERSION_WORK_AREA(coding, size)               \
   do {                                                         \
-    int units = (size) + MAX_CHARBUF_EXTRA_SIZE;               \
-                                                               \
-    if (units > MAX_CHARBUF_SIZE)                              \
-      units = MAX_CHARBUF_SIZE;                                        \
-    coding->charbuf = SAFE_ALLOCA ((units) * sizeof (int));    \
-    coding->charbuf_size = (units);                            \
+    ptrdiff_t units = min ((size) + MAX_CHARBUF_EXTRA_SIZE,    \
+                          MAX_CHARBUF_SIZE);                   \
+    coding->charbuf = SAFE_ALLOCA (units * sizeof (int));      \
+    coding->charbuf_size = units;                              \
   } while (0)
 
-
 static void
 produce_annotation (struct coding_system *coding, ptrdiff_t pos)
 {