- start of external Imager API access:

[imager.git] / palimg.c

diff --git a/palimg.c b/palimg.c
index 4fb43c8a894b1700b11d6d320c4d1b001f158613..90ec29e7048c7352738b8cff22012ee6b4ca452c 100644 (file)
--- a/palimg.c
+++ b/palimg.c
@@ -18,8 +18,8 @@ Basic 8-bit/sample paletted image
 =cut
 */
 
-#include "image.h"
-#include "imagei.h"
+#include "imager.h"
+#include "imageri.h"
 
 #define PALEXT(im) ((i_img_pal_ext*)((im)->ext_data))
 static int i_ppix_p(i_img *im, int x, int y, i_color *val);
@@ -74,7 +74,7 @@ static i_img IIM_base_8bit_pal =
 };
 
 /*
-=item i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal)
+=item i_img_pal_new_low(im, x, y, channels, maxpal)
 
 Creates a new paletted image.
 
@@ -84,9 +84,10 @@ Currently 0 < maxpal <= 256
 */
 i_img *i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal) {
   i_img_pal_ext *palext;
+  int bytes, line_bytes;
 
   i_clear_error();
-  if (maxpal < 0 || maxpal > 256) {
+  if (maxpal < 1 || maxpal > 256) {
     i_push_error(0, "Maximum of 256 palette entries");
     return NULL;
   }
@@ -95,7 +96,21 @@ i_img *i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal) {
     return NULL;
   }
   if (channels < 1 || channels > MAXCHANNELS) {
-    i_push_errorf(0, "Channels must be postive and <= %d", MAXCHANNELS);
+    i_push_errorf(0, "Channels must be positive and <= %d", MAXCHANNELS);
+    return NULL;
+  }
+  bytes = sizeof(i_palidx) * x * y;
+  if (bytes / y / sizeof(i_palidx) != x) {
+    i_push_error(0, "integer overflow calculating image allocation");
+    return NULL;
+  }
+
+  /* basic assumption: we can always allocate a buffer representing a
+     line from the image, otherwise we're going to have trouble
+     working with the image */
+  line_bytes = sizeof(i_color) * x;
+  if (line_bytes / x != sizeof(i_color)) {
+    i_push_error(0, "integer overflow calculating scanline allocation");
     return NULL;
   }
 
@@ -107,7 +122,7 @@ i_img *i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal) {
   palext->last_found = -1;
   im->ext_data = palext;
   i_tags_new(&im->tags);
-  im->bytes = sizeof(i_palidx) * x * y;
+  im->bytes = bytes;
   im->idata = mymalloc(im->bytes);
   im->channels = channels;
   memset(im->idata, 0, im->bytes);
@@ -117,11 +132,28 @@ i_img *i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal) {
   return im;
 }
 
+/*
+=item i_img_pal_new(x, y, channels, maxpal)
+
+=category Image creation
+
+Creates a new paletted image of the supplied dimensions.
+
+Returns a new image or NULL on failure.
+
+=cut
+*/
+
 i_img *i_img_pal_new(int x, int y, int channels, int maxpal) {
   i_img *im;
   mm_log((1, "i_img_pal_new(x %d, y %d, channels %d, maxpal %d)\n", x, y, channels, maxpal));
   im = mymalloc(sizeof(i_img));
-  return i_img_pal_new_low(im, x, y, channels, maxpal);
+  if (!i_img_pal_new_low(im, x, y, channels, maxpal)) {
+    myfree(im);
+    im = NULL;
+  }
+
+  return im;
 }
 
 /*
@@ -159,8 +191,6 @@ The conversion cannot be done for virtual images.
 */
 int i_img_to_rgb_inplace(i_img *im) {
   i_img temp;
-  i_color *pal;
-  int palsize;
 
   if (im->virtual)
     return 0;
@@ -189,20 +219,28 @@ Converts an RGB image to a paletted image
 i_img *i_img_to_pal(i_img *src, i_quantize *quant) {
   i_palidx *result;
   i_img *im;
+
+  i_clear_error();
   
-  im = i_img_pal_new(src->xsize, src->ysize, src->channels, quant->mc_size);
+  i_quant_makemap(quant, &src, 1);
+  result = i_quant_translate(quant, src);
 
-  quant_makemap(quant, &src, 1);
-  result = quant_translate(quant, src);
+  if (result) {
 
-  /* copy things over */
-  memcpy(im->idata, result, im->bytes);
-  PALEXT(im)->count = quant->mc_count;
-  memcpy(PALEXT(im)->pal, quant->mc_colors, sizeof(i_color) * quant->mc_count);
+    im = i_img_pal_new(src->xsize, src->ysize, src->channels, quant->mc_size);
 
-  myfree(result);
+    /* copy things over */
+    memcpy(im->idata, result, im->bytes);
+    PALEXT(im)->count = quant->mc_count;
+    memcpy(PALEXT(im)->pal, quant->mc_colors, sizeof(i_color) * quant->mc_count);
+    
+    myfree(result);
 
-  return im;
+    return im;
+  }
+  else {
+    return NULL;
+  }
 }
 
 /*
@@ -263,7 +301,7 @@ static int i_ppix_p(i_img *im, int x, int y, i_color *val) {
 }
 
 /*
-=item i_gpix(i_img *im, int x, int y, i_color *val)
+=item i_gpix_p(i_img *im, int x, int y, i_color *val)
 
 Retrieve a pixel, converting from a palette index to a color.
 
@@ -322,7 +360,7 @@ RGB.
 =cut
 */
 static int i_plin_p(i_img *im, int l, int r, int y, i_color *vals) {
-  int ch, count, i;
+  int count, i;
   i_palidx *data;
   i_palidx which;
   if (y >=0 && y < im->ysize && l < im->xsize && l >= 0) {
@@ -520,7 +558,7 @@ static int i_maxcolors_p(i_img *im) {
 =cut
 */
 static int i_setcolors_p(i_img *im, int index, i_color *colors, int count) {
-  if (index >= 0 && count >= 1 && index + count < PALEXT(im)->count) {
+  if (index >= 0 && count >= 1 && index + count <= PALEXT(im)->count) {
     while (count) {
       PALEXT(im)->pal[index++] = *colors++;
       --count;