mirror of
https://github.com/SwallowOS/image_pixman
synced 2025-12-26 07:11:05 +08:00
042f978b04
This program demonstrates three bugs relating to alpha maps: - When fetching from an alpha map into 32 bit intermediates, we use the fetcher from the image, and not the one from the alpha map. - For 64 bit intermediates we call fetch_pixel_generic_lossy_32() which then calls fetch_pixel_raw_64, which is NULL because alpha images are never validated. - The alpha map should be used *in place* of any existing alpha channel, but we are actually multiplying it onto the image.
46 lines
833 B
C
46 lines
833 B
C
#include <stdlib.h>
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#include <config.h>
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#include "pixman-private.h" /* For 'inline' definition */
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/* A primitive pseudorandom number generator,
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* taken from POSIX.1-2001 example
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*/
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extern uint32_t lcg_seed;
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static inline uint32_t
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lcg_rand (void)
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{
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lcg_seed = lcg_seed * 1103515245 + 12345;
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return ((uint32_t)(lcg_seed / 65536) % 32768);
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}
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static inline void
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lcg_srand (uint32_t seed)
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{
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lcg_seed = seed;
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}
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static inline uint32_t
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lcg_rand_n (int max)
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{
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return lcg_rand () % max;
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}
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/* CRC 32 computation
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*/
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uint32_t
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compute_crc32 (uint32_t in_crc32,
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const void *buf,
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size_t buf_len);
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/* perform endian conversion of pixel data
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*/
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void
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image_endian_swap (pixman_image_t *img, int bpp);
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/* Generate n_bytes random bytes in malloced memory */
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uint8_t *
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make_random_bytes (int n_bytes);
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