Update Potrace bitmap macros to upstream 1.13

(bzr r14449.1.2)

1 files changed, 9 insertions, 8 deletions

diff --git a/src/trace/potrace/bitmap.h b/src/trace/potrace/bitmap.h
index 086bbb046..7b5a94bb1 100644
--- a/src/trace/potrace/bitmap.h
+++ b/src/trace/potrace/bitmap.h
@@ -8,6 +8,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <stddef.h>
 
 /* The bitmap type is defined in potracelib.h */
 #include "potracelib.h"
@@ -28,7 +29,7 @@
 /* macros for accessing pixel at index (x,y). U* macros omit the
    bounds check. */
 
-#define bm_scanline(bm, y) ((bm)->map + (ssize_t)(y)*(ssize_t)(bm)->dy)
+#define bm_scanline(bm, y) ((bm)->map + (ptrdiff_t)(y)*(ptrdiff_t)(bm)->dy)
 #define bm_index(bm, x, y) (&bm_scanline(bm, y)[(x)/BM_WORDBITS])
 #define bm_mask(x) (BM_HIBIT >> ((x) & (BM_WORDBITS-1)))
 #define bm_range(x, a) ((int)(x) >= 0 && (int)(x) < (a))
@@ -57,10 +58,10 @@ static inline void bm_free(potrace_bitmap_t *bm) {
 static inline potrace_bitmap_t *bm_new(int w, int h) {
   potrace_bitmap_t *bm;
   int dy = w == 0 ? 0 : (w - 1) / BM_WORDBITS + 1;
-  ssize_t size = (ssize_t)dy * (ssize_t)h * (ssize_t)BM_WORDSIZE;
+  ptrdiff_t size = (ptrdiff_t)dy * (ptrdiff_t)h * (ptrdiff_t)BM_WORDSIZE;
 
   /* check for overflow error */
-  if (size < 0 || size / h / dy != BM_WORDSIZE) {
+  if (size < 0 || (h != 0 && dy != 0 && size / h / dy != BM_WORDSIZE)) {
     errno = ENOMEM;
     return NULL;
   }
@@ -83,15 +84,15 @@ static inline potrace_bitmap_t *bm_new(int w, int h) {
 /* clear the given bitmap. Set all bits to c. */
 static inline void bm_clear(potrace_bitmap_t *bm, int c) {
   /* Note: if the bitmap was created with bm_new, then it is
-     guaranteed that size will fit into the ssize_t type. */
-  ssize_t size = (ssize_t)bm->dy * (ssize_t)bm->h * (ssize_t)BM_WORDSIZE;
+     guaranteed that size will fit into the ptrdiff_t type. */
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h * (ptrdiff_t)BM_WORDSIZE;
   memset(bm->map, c ? -1 : 0, size);
 }
 
 /* duplicate the given bitmap. Return NULL on error with errno set. */
 static inline potrace_bitmap_t *bm_dup(const potrace_bitmap_t *bm) {
   potrace_bitmap_t *bm1 = bm_new(bm->w, bm->h);
-  ssize_t size = (ssize_t)bm->dy * (ssize_t)bm->h * (ssize_t)BM_WORDSIZE;
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h * (ptrdiff_t)BM_WORDSIZE;
   if (!bm1) {
     return NULL;
   }
@@ -101,8 +102,8 @@ static inline potrace_bitmap_t *bm_dup(const potrace_bitmap_t *bm) {
 
 /* invert the given bitmap. */
 static inline void bm_invert(potrace_bitmap_t *bm) {
-  ssize_t i;
-  ssize_t size = (ssize_t)bm->dy * (ssize_t)bm->h;
+  ptrdiff_t i;
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h;
 
   for (i = 0; i < size; i++) {
     bm->map[i] ^= BM_ALLBITS;