/*
* Copyright 2004 James Bursa <bursa@users.sourceforge.net>
* Copyright 2004 Richard Wilson <not_ginger_matt@hotmail.com>
* Copyright 2008 Daniel Silverstone <dsilvers@netsurf-browser.org>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* NetSurf 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include <png.h>
#include "desktop/plotters.h"
#include "content/content_protected.h"
#include "image/bitmap.h"
#include "image/image_cache.h"
#include "image/png.h"
#include "utils/log.h"
#include "utils/messages.h"
#include "utils/utils.h"
/* accommodate for old versions of libpng (beware security holes!) */
#ifndef png_jmpbuf
#warning you have an antique libpng
#define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
#endif
#if PNG_LIBPNG_VER < 10209
#define png_set_expand_gray_1_2_4_to_8(png) png_set_gray_1_2_4_to_8(png)
#endif
typedef struct nspng_content {
struct content base; /**< base content type */
bool no_process_data; /**< Do not continue to process data as it arrives */
png_structp png;
png_infop info;
int interlace;
struct bitmap *bitmap; /**< Created NetSurf bitmap */
size_t rowstride, bpp; /**< Bitmap rowstride and bpp */
size_t rowbytes; /**< Number of bytes per row */
} nspng_content;
static unsigned int interlace_start[8] = {0, 16, 0, 8, 0, 4, 0};
static unsigned int interlace_step[8] = {28, 28, 12, 12, 4, 4, 0};
static unsigned int interlace_row_start[8] = {0, 0, 4, 0, 2, 0, 1};
static unsigned int interlace_row_step[8] = {8, 8, 8, 4, 4, 2, 2};
/** Callbak error numbers*/
enum nspng_cberr {
CBERR_NONE = 0, /* no error */
CBERR_LIBPNG, /* error from png library */
CBERR_NOPRE, /* no pre-conversion performed */
};
/**
* nspng_warning -- callback for libpng warnings
*/
static void nspng_warning(png_structp png_ptr, png_const_charp warning_message)
{
LOG(("%s", warning_message));
}
/**
* nspng_error -- callback for libpng errors
*/
static void nspng_error(png_structp png_ptr, png_const_charp error_message)
{
LOG(("%s", error_message));
longjmp(png_jmpbuf
(png_ptr
), CBERR_LIBPNG
); }
static void nspng_setup_transforms(png_structp png_ptr, png_infop info_ptr)
{
int bit_depth, color_type, intent;
double gamma;
bit_depth = png_get_bit_depth(png_ptr, info_ptr);
color_type = png_get_color_type(png_ptr, info_ptr);
/* Set up our transformations */
if (color_type == PNG_COLOR_TYPE_PALETTE) {
png_set_palette_to_rgb(png_ptr);
}
if ((color_type == PNG_COLOR_TYPE_GRAY) && (bit_depth < 8)) {
png_set_expand_gray_1_2_4_to_8(png_ptr);
}
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
png_set_tRNS_to_alpha(png_ptr);
}
if (bit_depth == 16) {
png_set_strip_16(png_ptr);
}
if (color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
png_set_gray_to_rgb(png_ptr);
}
if (!(color_type & PNG_COLOR_MASK_ALPHA)) {
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
}
/* gamma correction - we use 2.2 as our screen gamma
* this appears to be correct (at least in respect to !Browse)
* see http://www.w3.org/Graphics/PNG/all_seven.html for a test case
*/
if (png_get_sRGB(png_ptr, info_ptr, &intent)) {
png_set_gamma(png_ptr, 2.2, 0.45455);
} else {
if (png_get_gAMA(png_ptr, info_ptr, &gamma)) {
png_set_gamma(png_ptr, 2.2, gamma);
} else {
png_set_gamma(png_ptr, 2.2, 0.45455);
}
}
png_read_update_info(png_ptr, info_ptr);
}
/**
* info_callback -- PNG header has been completely received, prepare to process
* image data
*/
static void info_callback(png_structp png_s, png_infop info)
{
int interlace;
png_uint_32 width, height;
nspng_content *png_c = png_get_progressive_ptr(png_s);
width = png_get_image_width(png_s, info);
height = png_get_image_height(png_s, info);
interlace = png_get_interlace_type(png_s, info);
png_c->base.width = width;
png_c->base.height = height;
png_c->base.size += width * height * 4;
/* see if progressive-conversion should continue */
if (image_cache_speculate((struct content *)png_c) == false) {
longjmp(png_jmpbuf
(png_s
), CBERR_NOPRE
); }
/* Claim the required memory for the converted PNG */
png_c->bitmap = bitmap_create(width, height, BITMAP_NEW);
if (png_c->bitmap == NULL) {
/* Failed to create bitmap skip pre-conversion */
longjmp(png_jmpbuf
(png_s
), CBERR_NOPRE
); }
png_c->rowstride = bitmap_get_rowstride(png_c->bitmap);
png_c->bpp = bitmap_get_bpp(png_c->bitmap);
nspng_setup_transforms(png_s, info);
png_c->rowbytes = png_get_rowbytes(png_s, info);
png_c->interlace = (interlace == PNG_INTERLACE_ADAM7);
LOG(("size %li * %li, rowbytes %zu", (unsigned long)width,
(unsigned long)height, png_c->rowbytes));
}
static void row_callback(png_structp png_s, png_bytep new_row,
png_uint_32 row_num, int pass)
{
nspng_content *png_c = png_get_progressive_ptr(png_s);
unsigned long rowbytes = png_c->rowbytes;
unsigned char *buffer, *row;
/* Give up if there's no bitmap */
if (png_c->bitmap == NULL)
return;
/* Abort if we've not got any data */
if (new_row == NULL)
return;
/* Get bitmap buffer */
buffer = bitmap_get_buffer(png_c->bitmap);
if (buffer == NULL) {
/* No buffer, bail out */
}
/* Calculate address of row start */
row = buffer + (png_c->rowstride * row_num);
/* Handle interlaced sprites using the Adam7 algorithm */
if (png_c->interlace) {
unsigned long dst_off;
unsigned long src_off = 0;
unsigned int start, step;
start = interlace_start[pass];
step = interlace_step[pass];
row_num = interlace_row_start[pass] +
interlace_row_step[pass] * row_num;
/* Copy the data to our current row taking interlacing
* into consideration */
row = buffer + (png_c->rowstride * row_num);
for (dst_off = start; dst_off < rowbytes; dst_off += step) {
row[dst_off++] = new_row[src_off++];
row[dst_off++] = new_row[src_off++];
row[dst_off++] = new_row[src_off++];
row[dst_off++] = new_row[src_off++];
}
} else {
/* Do a fast memcpy of the row data */
memcpy(row
, new_row
, rowbytes
); }
}
static void end_callback(png_structp png_s, png_infop info)
{
}
static nserror nspng_create_png_data(nspng_content *png_c)
{
union content_msg_data msg_data;
png_c->bitmap = NULL;
png_c->png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
if (png_c->png == NULL) {
msg_data.error = messages_get("NoMemory");
content_broadcast(&png_c->base, CONTENT_MSG_ERROR, msg_data);
warn_user("NoMemory", 0);
return NSERROR_NOMEM;
}
png_set_error_fn(png_c->png, NULL, nspng_error, nspng_warning);
png_c->info = png_create_info_struct(png_c->png);
if (png_c->info == NULL) {
png_destroy_read_struct(&png_c->png, &png_c->info, 0);
msg_data.error = messages_get("NoMemory");
content_broadcast(&png_c->base, CONTENT_MSG_ERROR, msg_data);
warn_user("NoMemory", 0);
return NSERROR_NOMEM;
}
if (setjmp(png_jmpbuf
(png_c
->png
))) { png_destroy_read_struct(&png_c->png, &png_c->info, 0);
LOG(("Failed to set callbacks"));
png_c->png = NULL;
png_c->info = NULL;
msg_data.error = messages_get("PNGError");
content_broadcast(&png_c->base, CONTENT_MSG_ERROR, msg_data);
return NSERROR_NOMEM;
}
png_set_progressive_read_fn(png_c->png, png_c,
info_callback, row_callback, end_callback);
return NSERROR_OK;
}
static nserror nspng_create(const content_handler *handler,
lwc_string *imime_type, const http_parameter *params,
llcache_handle *llcache, const char *fallback_charset,
bool quirks, struct content **c)
{
nspng_content *png_c;
nserror error;
png_c
= calloc(1, sizeof(nspng_content
)); if (png_c == NULL)
return NSERROR_NOMEM;
error = content__init(&png_c->base,
handler,
imime_type,
params,
llcache,
fallback_charset,
quirks);
if (error != NSERROR_OK) {
return error;
}
error = nspng_create_png_data(png_c);
if (error != NSERROR_OK) {
return error;
}
*c = (struct content *)png_c;
return NSERROR_OK;
}
static bool nspng_process_data(struct content *c, const char *data,
unsigned int size)
{
nspng_content *png_c = (nspng_content *)c;
union content_msg_data msg_data;
volatile bool ret = true;
if (png_c->no_process_data) {
return ret;
}
switch (setjmp(png_jmpbuf
(png_c
->png
))) { case CBERR_NONE: /* direct return */
png_process_data(png_c->png, png_c->info, (uint8_t *)data, size);
break;
case CBERR_NOPRE: /* not going to progressive convert */
png_c->no_process_data = true;
break;
default: /* fatal error from library processing png */
if (png_c->bitmap != NULL) {
/* A bitmap managed to get created so
* operation is past header and possibly some
* conversion happened before faliure.
*
* In this case keep the partial
* conversion. This is usually seen if a png
* has been truncated (often jsut lost its
* last byte and hence end of image marker)
*/
png_c->no_process_data = true;
} else {
/* not managed to progress past header, clean
* up png conversion and signal the content
* error
*/
LOG(("Fatal PNG error during header, error content"));
png_destroy_read_struct(&png_c->png, &png_c->info, 0);
png_c->png = NULL;
png_c->info = NULL;
msg_data.error = messages_get("PNGError");
content_broadcast(c, CONTENT_MSG_ERROR, msg_data);
ret = false;
}
break;
}
return ret;
}
struct png_cache_read_data_s {
const char *data;
unsigned long size;
};
/** PNG library read fucntion to read data from a memory array
*/
static void
png_cache_read_fn(png_structp png_ptr, png_bytep data, png_size_t length)
{
struct png_cache_read_data_s *png_cache_read_data;
png_cache_read_data = png_get_io_ptr(png_ptr);
if (length > png_cache_read_data->size) {
length = png_cache_read_data->size;
}
if (length == 0) {
png_error(png_ptr, "Read Error");
}
memcpy(data
, png_cache_read_data
->data
, length
);
png_cache_read_data->data += length;
png_cache_read_data->size -= length;
}
/** calculate an array of row pointers into a bitmap data area
*/
static png_bytep *calc_row_pointers(struct bitmap *bitmap)
{
int height = bitmap_get_height(bitmap);
unsigned char *buffer= bitmap_get_buffer(bitmap);
size_t rowstride = bitmap_get_rowstride(bitmap);
png_bytep *row_ptrs;
int hloop;
row_ptrs
= malloc(sizeof(png_bytep
) * height
);
if (row_ptrs != NULL) {
for (hloop = 0; hloop < height; hloop++) {
row_ptrs[hloop] = buffer + (rowstride * hloop);
}
}
return row_ptrs;
}
/** PNG content to bitmap conversion.
*
* This routine generates a bitmap object from a PNG image content
*/
static struct bitmap *
png_cache_convert(struct content *c)
{
png_structp png_ptr;
png_infop info_ptr;
png_infop end_info;
volatile struct bitmap *bitmap = NULL;
struct png_cache_read_data_s png_cache_read_data;
png_uint_32 width, height;
volatile png_bytep *row_pointers = NULL;
png_cache_read_data.data =
content__get_source_data(c, &png_cache_read_data.size);
if ((png_cache_read_data.data == NULL) ||
(png_cache_read_data.size <= 8)) {
return NULL;
}
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
NULL,
nspng_error,
nspng_warning);
if (png_ptr == NULL) {
return NULL;
}
info_ptr = png_create_info_struct(png_ptr);
if (png_ptr == NULL) {
png_destroy_read_struct(&png_ptr, NULL, NULL);
return NULL;
}
end_info = png_create_info_struct(png_ptr);
if (png_ptr == NULL) {
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
/* setup error exit path */
if (setjmp(png_jmpbuf
(png_ptr
))) { /* cleanup and bail */
goto png_cache_convert_error;
}
/* read from a buffer instead of stdio */
png_set_read_fn(png_ptr, &png_cache_read_data, png_cache_read_fn);
/* ensure the png info structure is populated */
png_read_info(png_ptr, info_ptr);
/* setup output transforms */
nspng_setup_transforms(png_ptr, info_ptr);
width = png_get_image_width(png_ptr, info_ptr);
height = png_get_image_height(png_ptr,info_ptr);
/* Claim the required memory for the converted PNG */
bitmap = bitmap_create(width, height, BITMAP_NEW);
if (bitmap == NULL) {
/* cleanup and bail */
goto png_cache_convert_error;
}
row_pointers = calc_row_pointers((struct bitmap *) bitmap);
if (row_pointers != NULL) {
png_read_image(png_ptr, (png_bytep *) row_pointers);
}
png_cache_convert_error:
/* cleanup png read */
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
free((png_bytep
*) row_pointers
);
if (bitmap != NULL)
bitmap_modified((struct bitmap *)bitmap);
return (struct bitmap *)bitmap;
}
static bool nspng_convert(struct content *c)
{
nspng_content *png_c = (nspng_content *) c;
char *title;
/* clean up png structures */
png_destroy_read_struct(&png_c->png, &png_c->info, 0);
/* set title text */
title = messages_get_buff("PNGTitle",
nsurl_access_leaf(llcache_handle_get_url(c->llcache)),
c->width, c->height);
if (title != NULL) {
content__set_title(c, title);
}
if (png_c->bitmap != NULL) {
bitmap_set_opaque(png_c->bitmap, bitmap_test_opaque(png_c->bitmap));
bitmap_modified(png_c->bitmap);
}
image_cache_add(c, png_c->bitmap, png_cache_convert);
content_set_ready(c);
content_set_done(c);
content_set_status(c, "");
return true;
}
static nserror nspng_clone(const struct content *old_c, struct content **new_c)
{
nspng_content *clone_png_c;
nserror error;
const char *data;
unsigned long size;
clone_png_c
= calloc(1, sizeof(nspng_content
)); if (clone_png_c == NULL)
return NSERROR_NOMEM;
error = content__clone(old_c, &clone_png_c->base);
if (error != NSERROR_OK) {
content_destroy(&clone_png_c->base);
return error;
}
/* Simply replay create/process/convert */
error = nspng_create_png_data(clone_png_c);
if (error != NSERROR_OK) {
content_destroy(&clone_png_c->base);
return error;
}
data = content__get_source_data(&clone_png_c->base, &size);
if (size > 0) {
if (nspng_process_data(&clone_png_c->base, data, size) == false) {
content_destroy(&clone_png_c->base);
return NSERROR_NOMEM;
}
}
if ((old_c->status == CONTENT_STATUS_READY) ||
(old_c->status == CONTENT_STATUS_DONE)) {
if (nspng_convert(&clone_png_c->base) == false) {
content_destroy(&clone_png_c->base);
return NSERROR_CLONE_FAILED;
}
}
*new_c = (struct content *)clone_png_c;
return NSERROR_OK;
}
static const content_handler nspng_content_handler = {
.create = nspng_create,
.process_data = nspng_process_data,
.data_complete = nspng_convert,
.clone = nspng_clone,
.destroy = image_cache_destroy,
.redraw = image_cache_redraw,
.get_internal = image_cache_get_internal,
.type = image_cache_content_type,
.no_share = false,
};
static const char *nspng_types[] = {
"image/png",
"image/x-png"
};
CONTENT_FACTORY_REGISTER_TYPES(nspng, nspng_types, nspng_content_handler);