summaryrefslogtreecommitdiff
path: root/fitz/image_png.c
diff options
context:
space:
mode:
Diffstat (limited to 'fitz/image_png.c')
-rw-r--r--fitz/image_png.c83
1 files changed, 41 insertions, 42 deletions
diff --git a/fitz/image_png.c b/fitz/image_png.c
index 7825eec2..bda959fe 100644
--- a/fitz/image_png.c
+++ b/fitz/image_png.c
@@ -7,7 +7,7 @@ struct info
fz_context *ctx;
unsigned int width, height, depth, n;
int interlace, indexed;
- int size;
+ unsigned int size;
unsigned char *samples;
unsigned char palette[256*4];
int transparency;
@@ -80,11 +80,11 @@ static inline int paeth(int a, int b, int c)
}
static void
-png_predict(unsigned char *samples, int width, int height, int n, int depth)
+png_predict(unsigned char *samples, unsigned int width, unsigned int height, unsigned int n, unsigned int depth)
{
- int stride = (width * n * depth + 7) / 8;
- int bpp = (n * depth + 7) / 8;
- int i, row;
+ unsigned int stride = (width * n * depth + 7) / 8;
+ unsigned int bpp = (n * depth + 7) / 8;
+ unsigned int i, row;
for (row = 0; row < height; row ++)
{
@@ -156,13 +156,13 @@ png_predict(unsigned char *samples, int width, int height, int n, int depth)
}
}
-static const int adam7_ix[7] = { 0, 4, 0, 2, 0, 1, 0 };
-static const int adam7_dx[7] = { 8, 8, 4, 4, 2, 2, 1 };
-static const int adam7_iy[7] = { 0, 0, 4, 0, 2, 0, 1 };
-static const int adam7_dy[7] = { 8, 8, 8, 4, 4, 2, 2 };
+static const unsigned int adam7_ix[7] = { 0, 4, 0, 2, 0, 1, 0 };
+static const unsigned int adam7_dx[7] = { 8, 8, 4, 4, 2, 2, 1 };
+static const unsigned int adam7_iy[7] = { 0, 0, 4, 0, 2, 0, 1 };
+static const unsigned int adam7_dy[7] = { 8, 8, 8, 4, 4, 2, 2 };
static void
-png_deinterlace_passes(struct info *info, int *w, int *h, int *ofs)
+png_deinterlace_passes(struct info *info, unsigned int *w, unsigned int *h, unsigned int *ofs)
{
int p, bpp = info->depth * info->n;
ofs[0] = 0;
@@ -180,21 +180,21 @@ png_deinterlace_passes(struct info *info, int *w, int *h, int *ofs)
}
static void
-png_deinterlace(struct info *info, int *passw, int *passh, int *passofs)
+png_deinterlace(struct info *info, unsigned int *passw, unsigned int *passh, unsigned int *passofs)
{
- int n = info->n;
- int depth = info->depth;
- int stride = (info->width * n * depth + 7) / 8;
+ unsigned int n = info->n;
+ unsigned int depth = info->depth;
+ unsigned int stride = (info->width * n * depth + 7) / 8;
unsigned char *output;
- int p, x, y, k;
+ unsigned int p, x, y, k;
output = fz_malloc_array(info->ctx, info->height, stride);
for (p = 0; p < 7; p++)
{
- unsigned char *sp = info->samples + (unsigned int)(passofs[p]);
- int w = passw[p];
- int h = passh[p];
+ unsigned char *sp = info->samples + (passofs[p]);
+ unsigned int w = passw[p];
+ unsigned int h = passh[p];
png_predict(sp, w, h, n, depth);
for (y = 0; y < h; y++)
@@ -219,7 +219,7 @@ png_deinterlace(struct info *info, int *passw, int *passh, int *passofs)
}
static void
-png_read_ihdr(struct info *info, unsigned char *p, int size)
+png_read_ihdr(struct info *info, unsigned char *p, unsigned int size)
{
int color, compression, filter;
@@ -278,7 +278,7 @@ png_read_ihdr(struct info *info, unsigned char *p, int size)
}
static void
-png_read_plte(struct info *info, unsigned char *p, int size)
+png_read_plte(struct info *info, unsigned char *p, unsigned int size)
{
int n = size / 3;
int i;
@@ -306,9 +306,9 @@ png_read_plte(struct info *info, unsigned char *p, int size)
}
static void
-png_read_trns(struct info *info, unsigned char *p, int size)
+png_read_trns(struct info *info, unsigned char *p, unsigned int size)
{
- int i;
+ unsigned int i;
info->transparency = 1;
@@ -335,7 +335,7 @@ png_read_trns(struct info *info, unsigned char *p, int size)
}
static void
-png_read_idat(struct info *info, unsigned char *p, int size, z_stream *stm)
+png_read_idat(struct info *info, unsigned char *p, unsigned int size, z_stream *stm)
{
int code;
@@ -354,7 +354,7 @@ png_read_idat(struct info *info, unsigned char *p, int size, z_stream *stm)
}
static void
-png_read_phys(struct info *info, unsigned char *p, int size)
+png_read_phys(struct info *info, unsigned char *p, unsigned int size)
{
if (size != 9)
fz_throw(info->ctx, "pHYs chunk is the wrong size");
@@ -366,9 +366,9 @@ png_read_phys(struct info *info, unsigned char *p, int size)
}
static void
-png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
+png_read_image(fz_context *ctx, struct info *info, unsigned char *p, unsigned int total)
{
- int passw[7], passh[7], passofs[8];
+ unsigned int passw[7], passh[7], passofs[8];
unsigned int code, size;
z_stream stm;
@@ -381,7 +381,7 @@ png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
/* Read signature */
if (total < 8 + 12 || memcmp(p, png_signature, 8))
- fz_throw(info->ctx, "not a png image (wrong signature)");
+ fz_throw(ctx, "not a png image (wrong signature)");
p += 8;
total -= 8;
@@ -389,14 +389,13 @@ png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
/* Read IHDR chunk (must come first) */
size = getuint(p);
-
- if (size + 12 > total)
- fz_throw(info->ctx, "premature end of data in png image");
+ if (total < 12 || size > total - 12)
+ fz_throw(ctx, "premature end of data in png image");
if (!memcmp(p + 4, "IHDR", 4))
png_read_ihdr(info, p + 8, size);
else
- fz_throw(info->ctx, "png file must start with IHDR chunk");
+ fz_throw(ctx, "png file must start with IHDR chunk");
p += size + 12;
total -= size + 12;
@@ -417,7 +416,7 @@ png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
stm.zalloc = zalloc;
stm.zfree = zfree;
- stm.opaque = info->ctx;
+ stm.opaque = ctx;
stm.next_out = info->samples;
stm.avail_out = info->size;
@@ -436,8 +435,8 @@ png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
{
size = getuint(p);
- if (size + 12 > total)
- fz_throw(info->ctx, "premature end of data in png image");
+ if (total < 12 || size > total - 12)
+ fz_throw(ctx, "premature end of data in png image");
if (!memcmp(p + 4, "PLTE", 4))
png_read_plte(info, p + 8, size);
@@ -465,7 +464,7 @@ png_read_image(fz_context *ctx, struct info *info, unsigned char *p, int total)
if (code != Z_OK)
{
fz_free(ctx, info->samples);
- fz_throw(info->ctx, "zlib error: %s", stm.msg);
+ fz_throw(ctx, "zlib error: %s", stm.msg);
}
/* Apply prediction filter and deinterlacing */
@@ -489,14 +488,14 @@ png_expand_palette(fz_context *ctx, struct info *info, fz_pixmap *src)
fz_pixmap *dst = fz_new_pixmap(ctx, fz_device_rgb, src->w, src->h);
unsigned char *sp = src->samples;
unsigned char *dp = dst->samples;
- int x, y;
+ unsigned int x, y;
dst->xres = src->xres;
dst->yres = src->yres;
- for (y = 0; y < info->height; y++)
+ for (y = info->height; y > 0; y--)
{
- for (x = 0; x < info->width; x++)
+ for (x = info->width; x > 0; x--)
{
int v = *sp << 2;
*dp++ = info->palette[v];
@@ -514,10 +513,10 @@ png_expand_palette(fz_context *ctx, struct info *info, fz_pixmap *src)
static void
png_mask_transparency(struct info *info, fz_pixmap *dst)
{
- int stride = (info->width * info->n * info->depth + 7) / 8;
- int depth = info->depth;
- int n = info->n;
- int x, y, k, t;
+ unsigned int stride = (info->width * info->n * info->depth + 7) / 8;
+ unsigned int depth = info->depth;
+ unsigned int n = info->n;
+ unsigned int x, y, k, t;
for (y = 0; y < info->height; y++)
{
generated by cgit v1.2.3 (git 2.25.1) at 2025-02-24 17:00:23 +0000