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gtk/gdk-pixbuf/io-pnm.c
Matthias Clasen b839a7b0c6 Check for overflow. (#306394, Morten Welinder) 
2005-06-08  Matthias Clasen  <mclasen@redhat.com>

	* io-pnm.c (pnm_read_next_value): Check for overflow.
	(#306394, Morten Welinder)
2005-06-08 20:57:16 +00:00

1095 lines
26 KiB
C
Raw Blame History

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* GdkPixbuf library - PNM image loader
*
* Copyright (C) 1999 Red Hat, Inc.
*
* Authors: Jeffrey Stedfast <fejj@helixcode.com>
* Michael Fulbright <drmike@redhat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
#include "gdk-pixbuf-private.h"
#include "gdk-pixbuf-io.h"
#define PNM_BUF_SIZE 4096
#define PNM_FATAL_ERR -1
#define PNM_SUSPEND 0
#define PNM_OK 1
typedef enum {
PNM_FORMAT_PGM = 1,
PNM_FORMAT_PGM_RAW,
PNM_FORMAT_PPM,
PNM_FORMAT_PPM_RAW,
PNM_FORMAT_PBM,
PNM_FORMAT_PBM_RAW
} PnmFormat;
typedef struct {
guchar buffer[PNM_BUF_SIZE];
guchar *byte;
guint nbytes;
} PnmIOBuffer;
typedef struct {
GdkPixbufModuleUpdatedFunc updated_func;
GdkPixbufModulePreparedFunc prepared_func;
GdkPixbufModuleSizeFunc size_func;
gpointer user_data;
GdkPixbuf *pixbuf;
guchar *pixels; /* incoming pixel data buffer */
guchar *dptr; /* current position in pixbuf */
PnmIOBuffer inbuf;
guint width;
guint height;
guint maxval;
guint rowstride;
PnmFormat type;
guint output_row; /* last row to be completed */
guint output_col;
gboolean did_prescan; /* are we in image data yet? */
gboolean got_header; /* have we loaded pnm header? */
guint scan_state;
GError **error;
} PnmLoaderContext;
static GdkPixbuf *gdk_pixbuf__pnm_image_load (FILE *f, GError **error);
static gpointer gdk_pixbuf__pnm_image_begin_load (GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc func,
GdkPixbufModuleUpdatedFunc func2,
gpointer user_data,
GError **error);
static gboolean gdk_pixbuf__pnm_image_stop_load (gpointer context, GError **error);
static gboolean gdk_pixbuf__pnm_image_load_increment (gpointer context,
const guchar *buf, guint size,
GError **error);
static void explode_bitmap_into_buf (PnmLoaderContext *context);
static void explode_gray_into_buf (PnmLoaderContext *context);
/* explode bitmap data into rgb components */
/* we need to know what the row so we can */
/* do sub-byte expansion (since 1 byte = 8 pixels) */
/* context->dptr MUST point at first byte in incoming data */
/* which corresponds to first pixel of row y */
static void
explode_bitmap_into_buf (PnmLoaderContext *context)
{
gint j;
guchar *from, *to, data;
gint bit;
guchar *dptr;
gint wid, x, y;
g_return_if_fail (context != NULL);
g_return_if_fail (context->dptr != NULL);
/* I'm no clever bit-hacker so I'm sure this can be optimized */
dptr = context->dptr;
y = context->output_row;
wid = context->width;
from = dptr + ((wid - 1) / 8);
to = dptr + (wid - 1) * 3;
/* bit = 7 - (((y+1)*wid-1) % 8); */
bit = 7 - ((wid-1) % 8);
/* get first byte and align properly */
data = from[0];
for (j = 0; j < bit; j++, data >>= 1);
for (x = wid-1; x >= 0; x--) {
/* g_print ("%c", (data & 1) ? '*' : ' '); */
to[0] = to[1] = to[2] = (data & 0x01) ? 0x00 : 0xff;
to -= 3;
bit++;
if (bit > 7) {
from--;
data = from[0];
bit = 0;
} else {
data >>= 1;
}
}
/* g_print ("\n"); */
}
/* explode gray image row into rgb components in pixbuf */
static void
explode_gray_into_buf (PnmLoaderContext *context)
{
gint j;
guchar *from, *to;
guint w;
g_return_if_fail (context != NULL);
g_return_if_fail (context->dptr != NULL);
/* Expand grey->colour. Expand from the end of the
* memory down, so we can use the same buffer.
*/
w = context->width;
from = context->dptr + w - 1;
to = context->dptr + (w - 1) * 3;
for (j = w - 1; j >= 0; j--) {
to[0] = from[0];
to[1] = from[0];
to[2] = from[0];
to -= 3;
from--;
}
}
/* skip over whitespace and comments in input buffer */
static gint
pnm_skip_whitespace (PnmIOBuffer *inbuf, GError **error)
{
register guchar *inptr;
guchar *inend;
g_return_val_if_fail (inbuf != NULL, PNM_FATAL_ERR);
g_return_val_if_fail (inbuf->byte != NULL, PNM_FATAL_ERR);
inend = inbuf->byte + inbuf->nbytes;
inptr = inbuf->byte;
for ( ; inptr < inend; inptr++) {
if (*inptr == '#') {
/* in comment - skip to the end of this line */
for ( ; *inptr != '\n' && inptr < inend; inptr++)
;
if ( inptr == inend || *inptr != '\n' ) {
/* couldn't read whole comment */
return PNM_SUSPEND;
}
} else if (!g_ascii_isspace (*inptr)) {
inbuf->byte = inptr;
inbuf->nbytes = (guint) (inend - inptr);
return PNM_OK;
}
}
inbuf->byte = inptr;
inbuf->nbytes = (guint) (inend - inptr);
return PNM_SUSPEND;
}
/* read next number from buffer */
static gint
pnm_read_next_value (PnmIOBuffer *inbuf, gint max_length, guint *value, GError **error)
{
register guchar *inptr, *word, *p;
guchar *inend, buf[129];
gchar *endptr;
gint retval;
glong result;
g_return_val_if_fail (inbuf != NULL, PNM_FATAL_ERR);
g_return_val_if_fail (inbuf->byte != NULL, PNM_FATAL_ERR);
g_return_val_if_fail (value != NULL, PNM_FATAL_ERR);
if (max_length < 0)
max_length = 128;
/* skip white space */
if ((retval = pnm_skip_whitespace (inbuf, error)) != PNM_OK)
return retval;
inend = inbuf->byte + inbuf->nbytes;
inptr = inbuf->byte;
/* copy this pnm 'word' into a temp buffer */
for (p = inptr, word = buf; (p < inend) && !g_ascii_isspace (*p) && (*p != '#') && (p - inptr < max_length); p++, word++)
*word = *p;
*word = '\0';
/* hmmm, there must be more data to this 'word' */
if (p == inend || (!g_ascii_isspace (*p) && (*p != '#') && (p - inptr < max_length)))
return PNM_SUSPEND;
/* get the value */
result = strtol (buf, &endptr, 10);
if (*endptr != '\0' || result < 0 || result > G_MAXUINT) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM loader expected to find an integer, but didn't"));
return PNM_FATAL_ERR;
}
*value = result;
inbuf->byte = p;
inbuf->nbytes = (guint) (inend - p);
return PNM_OK;
}
/* returns PNM_OK, PNM_SUSPEND, or PNM_FATAL_ERR */
static gint
pnm_read_header (PnmLoaderContext *context)
{
PnmIOBuffer *inbuf;
gint retval;
g_return_val_if_fail (context != NULL, PNM_FATAL_ERR);
inbuf = &context->inbuf;
if (!context->type) {
/* file must start with a 'P' followed by a numeral */
/* so loop till we get enough data to determine type */
if (inbuf->nbytes < 2)
return PNM_SUSPEND;
if (*inbuf->byte != 'P') {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM file has an incorrect initial byte"));
return PNM_FATAL_ERR;
}
inbuf->byte++;
inbuf->nbytes--;
switch (*inbuf->byte) {
case '1':
context->type = PNM_FORMAT_PBM;
break;
case '2':
context->type = PNM_FORMAT_PGM;
break;
case '3':
context->type = PNM_FORMAT_PPM;
break;
case '4':
context->type = PNM_FORMAT_PBM_RAW;
break;
case '5':
context->type = PNM_FORMAT_PGM_RAW;
break;
case '6':
context->type = PNM_FORMAT_PPM_RAW;
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM file is not in a recognized PNM subformat"));
return PNM_FATAL_ERR;
}
if (!inbuf->nbytes)
return PNM_SUSPEND;
inbuf->byte++;
inbuf->nbytes--;
}
if (!context->width) {
/* read the pixmap width */
guint width = 0;
retval = pnm_read_next_value (inbuf, -1, &width,
context->error);
if (retval != PNM_OK)
return retval;
if (!width) {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM file has an image width of 0"));
return PNM_FATAL_ERR;
}
context->width = width;
}
if (!context->height) {
/* read the pixmap height */
guint height = 0;
retval = pnm_read_next_value (inbuf, -1, &height,
context->error);
if (retval != PNM_OK)
return retval;
if (!height) {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM file has an image height of 0"));
return PNM_FATAL_ERR;
}
context->height = height;
}
switch (context->type) {
case PNM_FORMAT_PPM:
case PNM_FORMAT_PPM_RAW:
case PNM_FORMAT_PGM:
case PNM_FORMAT_PGM_RAW:
if (!context->maxval) {
retval = pnm_read_next_value (inbuf, -1, &context->maxval,
context->error);
if (retval != PNM_OK)
return retval;
if (context->maxval == 0) {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Maximum color value in PNM file is 0"));
return PNM_FATAL_ERR;
}
if (context->maxval > 65535) {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Maximum color value in PNM file is too large"));
return PNM_FATAL_ERR;
}
if (context->maxval > 255) {
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Cannot handle PNM files with maximum color values greater than 255"));
return PNM_FATAL_ERR;
}
}
break;
default:
break;
}
return PNM_OK;
}
static gint
pnm_read_raw_scanline (PnmLoaderContext *context)
{
PnmIOBuffer *inbuf;
guint numbytes, offset;
guint numpix = 0;
guchar *dest;
guint i;
g_return_val_if_fail (context != NULL, PNM_FATAL_ERR);
inbuf = &context->inbuf;
switch (context->type) {
case PNM_FORMAT_PBM_RAW:
numpix = inbuf->nbytes * 8;
break;
case PNM_FORMAT_PGM_RAW:
numpix = inbuf->nbytes;
break;
case PNM_FORMAT_PPM_RAW:
numpix = inbuf->nbytes / 3;
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Raw PNM image type is invalid"));
return PNM_FATAL_ERR;
}
numpix = MIN (numpix, context->width - context->output_col);
if (!numpix)
return PNM_SUSPEND;
context->dptr = context->pixels + context->output_row * context->rowstride;
switch (context->type) {
case PNM_FORMAT_PBM_RAW:
numbytes = (numpix / 8) + ((numpix % 8) ? 1 : 0);
offset = context->output_col / 8;
break;
case PNM_FORMAT_PGM_RAW:
numbytes = numpix;
offset = context->output_col;
break;
case PNM_FORMAT_PPM_RAW:
numbytes = numpix * 3;
offset = context->output_col * 3;
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Raw PNM image type is invalid"));
return PNM_FATAL_ERR;
}
switch (context->type) {
case PNM_FORMAT_PBM_RAW:
dest = context->dptr + offset;
memcpy (dest, inbuf->byte, numbytes);
break;
case PNM_FORMAT_PGM_RAW:
case PNM_FORMAT_PPM_RAW:
dest = context->dptr + offset;
if (context->maxval == 255) {
/* special-case optimization */
memcpy (dest, inbuf->byte, numbytes);
} else {
for (i = 0; i < numbytes; i++) {
guchar *byte = inbuf->byte + i;
/* scale the color to an 8-bit color depth */
if (*byte > context->maxval)
*dest++ = 255;
else
*dest++ = (guchar) (255 * *byte / context->maxval);
}
}
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Raw PNM image type is invalid"));
return PNM_FATAL_ERR;
}
inbuf->byte += numbytes;
inbuf->nbytes -= numbytes;
context->output_col += numpix;
if (context->output_col == context->width) {
if (context->type == PNM_FORMAT_PBM_RAW)
explode_bitmap_into_buf (context);
else if (context->type == PNM_FORMAT_PGM_RAW)
explode_gray_into_buf (context);
context->output_col = 0;
context->output_row++;
} else {
return PNM_SUSPEND;
}
return PNM_OK;
}
static gint
pnm_read_ascii_scanline (PnmLoaderContext *context)
{
PnmIOBuffer *inbuf;
guint offset;
guint value, numval, i;
guchar data;
guchar mask;
guchar *dptr;
gint retval;
gint max_length;
g_return_val_if_fail (context != NULL, PNM_FATAL_ERR);
data = mask = 0;
inbuf = &context->inbuf;
context->dptr = context->pixels + context->output_row * context->rowstride;
switch (context->type) {
case PNM_FORMAT_PBM:
max_length = 1;
numval = MIN (8, context->width - context->output_col);
offset = context->output_col / 8;
break;
case PNM_FORMAT_PGM:
max_length = -1;
numval = 1;
offset = context->output_col;
break;
case PNM_FORMAT_PPM:
max_length = -1;
numval = 3;
offset = context->output_col * 3;
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM image format is invalid"));
return PNM_FATAL_ERR;
}
dptr = context->dptr + offset + context->scan_state;
while (TRUE) {
if (context->type == PNM_FORMAT_PBM) {
mask = 0x80;
data = 0;
numval = MIN (8, context->width - context->output_col);
}
for (i = context->scan_state; i < numval; i++) {
retval = pnm_read_next_value (inbuf, max_length,
&value, context->error);
if (retval != PNM_OK) {
/* save state and return */
context->scan_state = i;
return retval;
}
switch (context->type) {
case PNM_FORMAT_PBM:
if (value)
data |= mask;
mask >>= 1;
break;
case PNM_FORMAT_PGM:
case PNM_FORMAT_PPM:
/* scale the color to an 8-bit color depth */
if (value > context->maxval)
*dptr++ = 255;
else
*dptr++ = (guchar)(255 * value / context->maxval);
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("PNM image format is invalid"));
return PNM_FATAL_ERR;
break;
}
}
context->scan_state = 0;
if (context->type == PNM_FORMAT_PBM) {
*dptr++ = data;
context->output_col += numval;
} else {
context->output_col++;
}
if (context->output_col == context->width) {
if (context->type == PNM_FORMAT_PBM)
explode_bitmap_into_buf (context);
else if (context->type == PNM_FORMAT_PGM)
explode_gray_into_buf (context);
context->output_col = 0;
context->output_row++;
break;
}
}
return PNM_OK;
}
/* returns 1 if a scanline was converted, 0 means we ran out of data */
static gint
pnm_read_scanline (PnmLoaderContext *context)
{
gint retval;
g_return_val_if_fail (context != NULL, PNM_FATAL_ERR);
/* read in image data */
/* for raw formats this is trivial */
switch (context->type) {
case PNM_FORMAT_PBM_RAW:
case PNM_FORMAT_PGM_RAW:
case PNM_FORMAT_PPM_RAW:
retval = pnm_read_raw_scanline (context);
if (retval != PNM_OK)
return retval;
break;
case PNM_FORMAT_PBM:
case PNM_FORMAT_PGM:
case PNM_FORMAT_PPM:
retval = pnm_read_ascii_scanline (context);
if (retval != PNM_OK)
return retval;
break;
default:
g_set_error (context->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
_("PNM image loader does not support this PNM subformat"));
return PNM_FATAL_ERR;
}
return PNM_OK;
}
/* Shared library entry point */
static GdkPixbuf *
gdk_pixbuf__pnm_image_load (FILE *f, GError **error)
{
PnmLoaderContext context;
PnmIOBuffer *inbuf;
gint nbytes;
gint retval;
/* pretend to be doing progressive loading */
context.updated_func = NULL;
context.prepared_func = NULL;
context.user_data = NULL;
context.type = 0;
context.inbuf.nbytes = 0;
context.inbuf.byte = NULL;
context.width = 0;
context.height = 0;
context.maxval = 0;
context.pixels = NULL;
context.pixbuf = NULL;
context.got_header = FALSE;
context.did_prescan = FALSE;
context.scan_state = 0;
context.error = error;
inbuf = &context.inbuf;
while (TRUE) {
guint num_to_read;
/* keep buffer as full as possible */
num_to_read = PNM_BUF_SIZE - inbuf->nbytes;
if (inbuf->byte != NULL && inbuf->nbytes > 0)
memmove (inbuf->buffer, inbuf->byte, inbuf->nbytes);
nbytes = fread (inbuf->buffer + inbuf->nbytes, 1, num_to_read, f);
/* error checking */
if (nbytes == 0) {
/* we ran out of data? */
if (context.pixbuf)
g_object_unref (context.pixbuf);
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Premature end-of-file encountered"));
return NULL;
}
inbuf->nbytes += nbytes;
inbuf->byte = inbuf->buffer;
/* get header if needed */
if (!context.got_header) {
retval = pnm_read_header (&context);
if (retval == PNM_FATAL_ERR)
return NULL;
else if (retval == PNM_SUSPEND)
continue;
context.got_header = TRUE;
}
/* scan until we hit image data */
if (!context.did_prescan) {
switch (context.type) {
case PNM_FORMAT_PBM_RAW:
case PNM_FORMAT_PGM_RAW:
case PNM_FORMAT_PPM_RAW:
if (inbuf->nbytes <= 0)
continue;
/* raw formats require exactly one whitespace */
if (!g_ascii_isspace(*(inbuf->byte)))
{
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Raw PNM formats require exactly one whitespace before sample data"));
return NULL;
}
inbuf->nbytes--;
inbuf->byte++;
break;
default:
retval = pnm_skip_whitespace (inbuf,
context.error);
if (retval == PNM_FATAL_ERR)
return NULL;
else if (retval == PNM_SUSPEND)
continue;
break;
}
context.did_prescan = TRUE;
context.output_row = 0;
context.output_col = 0;
context.pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8,
context.width, context.height);
if (!context.pixbuf) {
/* Failed to allocate memory */
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Cannot allocate memory for loading PNM image"));
return NULL;
}
context.rowstride = context.pixbuf->rowstride;
context.pixels = context.pixbuf->pixels;
}
/* if we got here we're reading image data */
while (context.output_row < context.height) {
retval = pnm_read_scanline (&context);
if (retval == PNM_SUSPEND) {
break;
} else if (retval == PNM_FATAL_ERR) {
if (context.pixbuf)
g_object_unref (context.pixbuf);
return NULL;
}
}
if (context.output_row < context.height)
continue;
else
break;
}
return context.pixbuf;
}
/*
* func - called when we have pixmap created (but no image data)
* user_data - passed as arg 1 to func
* return context (opaque to user)
*/
static gpointer
gdk_pixbuf__pnm_image_begin_load (GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error)
{
PnmLoaderContext *context;
context = g_try_malloc (sizeof (PnmLoaderContext));
if (!context) {
g_set_error(error, GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Insufficient memory to load PNM context struct"));
return NULL;
}
memset (context, 0, sizeof (PnmLoaderContext));
context->size_func = size_func;
context->prepared_func = prepared_func;
context->updated_func = updated_func;
context->user_data = user_data;
context->width = 0;
context->height = 0;
context->maxval = 0;
context->pixbuf = NULL;
context->pixels = NULL;
context->got_header = FALSE;
context->did_prescan = FALSE;
context->scan_state = 0;
context->inbuf.nbytes = 0;
context->inbuf.byte = NULL;
context->error = error;
return (gpointer) context;
}
/*
* context - returned from image_begin_load
*
* free context, unref gdk_pixbuf
*/
static gboolean
gdk_pixbuf__pnm_image_stop_load (gpointer data,
GError **error)
{
PnmLoaderContext *context = (PnmLoaderContext *) data;
gboolean retval = TRUE;
g_return_val_if_fail (context != NULL, TRUE);
if (context->pixbuf)
g_object_unref (context->pixbuf);
#if 0
/* We should ignore trailing newlines and we can't
generally complain about trailing stuff at all, since
pnm allows to put multiple images in a file
*/
if (context->inbuf.nbytes > 0) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Unexpected end of PNM image data"));
retval = FALSE;
}
#endif
g_free (context);
return retval;
}
/*
* context - from image_begin_load
* buf - new image data
* size - length of new image data
*
* append image data onto inrecrementally built output image
*/
static gboolean
gdk_pixbuf__pnm_image_load_increment (gpointer data,
const guchar *buf, guint size,
GError **error)
{
PnmLoaderContext *context = (PnmLoaderContext *)data;
PnmIOBuffer *inbuf;
guchar *old_byte;
guint old_nbytes;
const guchar *bufhd;
guint num_left, spinguard;
gint retval;
g_return_val_if_fail (context != NULL, FALSE);
g_return_val_if_fail (buf != NULL, FALSE);
context->error = error;
bufhd = buf;
inbuf = &context->inbuf;
old_nbytes = inbuf->nbytes;
old_byte = inbuf->byte;
num_left = size;
spinguard = 0;
while (TRUE) {
guint num_to_copy;
/* keep buffer as full as possible */
num_to_copy = MIN (PNM_BUF_SIZE - inbuf->nbytes, num_left);
if (num_to_copy == 0)
spinguard++;
if (spinguard > 1)
return TRUE;
if (inbuf->byte != NULL && inbuf->nbytes > 0)
memmove (inbuf->buffer, inbuf->byte, inbuf->nbytes);
memcpy (inbuf->buffer + inbuf->nbytes, bufhd, num_to_copy);
bufhd += num_to_copy;
inbuf->nbytes += num_to_copy;
inbuf->byte = inbuf->buffer;
num_left -= num_to_copy;
/* ran out of data and we haven't exited main loop */
if (inbuf->nbytes == 0)
return TRUE;
/* get header if needed */
if (!context->got_header) {
retval = pnm_read_header (context);
if (retval == PNM_FATAL_ERR)
return FALSE;
else if (retval == PNM_SUSPEND)
continue;
context->got_header = TRUE;
}
if (context->size_func) {
gint w = context->width;
gint h = context->height;
(*context->size_func) (&w, &h, context->user_data);
if (w == 0 || h == 0)
return FALSE;
}
/* scan until we hit image data */
if (!context->did_prescan) {
switch (context->type) {
case PNM_FORMAT_PBM_RAW:
case PNM_FORMAT_PGM_RAW:
case PNM_FORMAT_PPM_RAW:
if (inbuf->nbytes <= 0)
continue;
/* raw formats require exactly one whitespace */
if (!g_ascii_isspace(*(inbuf->byte)))
{
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Raw PNM formats require exactly one whitespace before sample data"));
return FALSE;
}
inbuf->nbytes--;
inbuf->byte++;
break;
default:
retval = pnm_skip_whitespace (inbuf,
context->error);
if (retval == PNM_FATAL_ERR)
return FALSE;
else if (retval == PNM_SUSPEND)
continue;
break;
}
context->did_prescan = TRUE;
context->output_row = 0;
context->output_col = 0;
context->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
FALSE,
8,
context->width,
context->height);
if (context->pixbuf == NULL) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Insufficient memory to load PNM file"));
return FALSE;
}
context->pixels = context->pixbuf->pixels;
context->rowstride = context->pixbuf->rowstride;
/* Notify the client that we are ready to go */
(* context->prepared_func) (context->pixbuf,
NULL,
context->user_data);
}
/* if we got here we're reading image data */
while (context->output_row < context->height) {
retval = pnm_read_scanline (context);
if (retval == PNM_SUSPEND) {
break;
} else if (retval == PNM_FATAL_ERR) {
return FALSE;
} else if (retval == PNM_OK) {
/* send updated signal */
(* context->updated_func) (context->pixbuf,
0,
context->output_row-1,
context->width,
1,
context->user_data);
}
}
if (context->output_row < context->height)
continue;
else
break;
}
return TRUE;
}
void
MODULE_ENTRY (pnm, fill_vtable) (GdkPixbufModule *module)
{
module->load = gdk_pixbuf__pnm_image_load;
module->begin_load = gdk_pixbuf__pnm_image_begin_load;
module->stop_load = gdk_pixbuf__pnm_image_stop_load;
module->load_increment = gdk_pixbuf__pnm_image_load_increment;
}
void
MODULE_ENTRY (pnm, fill_info) (GdkPixbufFormat *info)
{
static GdkPixbufModulePattern signature[] = {
{ "P1", NULL, 100 },
{ "P2", NULL, 100 },
{ "P3", NULL, 100 },
{ "P4", NULL, 100 },
{ "P5", NULL, 100 },
{ "P6", NULL, 100 },
{ NULL, NULL, 0 }
};
static gchar * mime_types[] = {
"image/x-portable-anymap",
"image/x-portable-bitmap",
"image/x-portable-graymap",
"image/x-portable-pixmap",
NULL
};
static gchar * extensions[] = {
"pnm",
"pbm",
"pgm",
"ppm",
NULL
};
info->name = "pnm";
info->signature = signature;
info->description = N_("The PNM/PBM/PGM/PPM image format family");
info->mime_types = mime_types;
info->extensions = extensions;
info->flags = GDK_PIXBUF_FORMAT_THREADSAFE;
info->license = "LGPL";
}
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