taisei/src/util/pngcruft.c
Andrei Alexeyev b6978178b1
memory: use custom memory allocation wrappers
Introduces wrappers around memory allocation functions in `memory.h`
that should be used instead of the standard C ones.

These never return NULL and, with the exception of `mem_realloc()`,
zero-initialize the allocated memory like `calloc()` does.

All allocations made with the memory.h API must be deallocated with
`mem_free()`. Although standard `free()` will work on some platforms,
it's not portable (currently it won't work on Windows). Likewise,
`mem_free()` must not be used to free foreign allocations.

The standard C allocation functions are now diagnosed as deprecated.
They are, however, available with the `libc_` prefix in case interfacing
with foreign APIs is required. So far they are only used to implement
`memory.h`.

Perhaps the most important change is the introduction of the `ALLOC()`,
`ALLOC_ARRAY()`, and `ALLOC_FLEX()` macros. They take a type as a
parameter, and allocate enough memory with the correct alignment for
that type. That includes overaligned types as well. In most
circumstances you should prefer to use these macros. See the `memory.h`
header for some usage examples.
2023-01-18 13:23:22 +01:00

69 lines
2 KiB
C

/*
* This software is licensed under the terms of the MIT License.
* See COPYING for further information.
* ---
* Copyright (c) 2011-2019, Lukas Weber <laochailan@web.de>.
* Copyright (c) 2012-2019, Andrei Alexeyev <akari@taisei-project.org>.
*/
#include "taisei.h"
#include "pngcruft.h"
#include "log.h"
static void pngutil_rwops_write_data(png_structp png_ptr, png_bytep data, png_size_t length) {
SDL_RWops *out = png_get_io_ptr(png_ptr);
SDL_RWwrite(out, data, length, 1);
}
static void pngutil_rwops_flush_data(png_structp png_ptr) {
// no flush operation in SDL_RWops
}
static void pngutil_rwops_read_data(png_structp png_ptr, png_bytep data, png_size_t length) {
SDL_RWops *out = png_get_io_ptr(png_ptr);
SDL_RWread(out, data, length, 1);
}
void pngutil_init_rwops_read(png_structp png, SDL_RWops *rwops) {
png_set_read_fn(png, rwops, pngutil_rwops_read_data);
}
void pngutil_init_rwops_write(png_structp png, SDL_RWops *rwops) {
png_set_write_fn(png, rwops, pngutil_rwops_write_data, pngutil_rwops_flush_data);
}
noreturn static void pngutil_error_handler(png_structp png_ptr, png_const_charp error_msg) {
log_error("PNG error: %s", error_msg);
png_longjmp(png_ptr, 1);
}
static void pngutil_warning_handler(png_structp png_ptr, png_const_charp warning_msg) {
log_warn("PNG warning: %s", warning_msg);
}
void pngutil_setup_error_handlers(png_structp png) {
png_set_error_fn(png, NULL, pngutil_error_handler, pngutil_warning_handler);
}
static PNG_CALLBACK(png_voidp, pngutil_malloc, (png_structp png, png_alloc_size_t size)) {
return mem_alloc(size);
}
static PNG_CALLBACK(void, pngutil_free, (png_structp png, png_voidp ptr)) {
mem_free(ptr);
}
png_structp pngutil_create_read_struct(void) {
return png_create_read_struct_2(
PNG_LIBPNG_VER_STRING,
NULL, pngutil_error_handler, pngutil_warning_handler,
NULL, pngutil_malloc, pngutil_free);
}
png_structp pngutil_create_write_struct(void) {
return png_create_write_struct_2(
PNG_LIBPNG_VER_STRING,
NULL, pngutil_error_handler, pngutil_warning_handler,
NULL, pngutil_malloc, pngutil_free);
}