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#ifndef _LIBZBITMAP_H
#define _LIBZBITMAP_H
#include <stddef.h>
#define ZBM_NOMEM (-1) /* Failed to allocate memory */
#define ZBM_INVAL (-2) /* Compressed input is invalid */
#define ZBM_RANGE (-3) /* The destination buffer is too small */
#define ZBM_OVERFLOW (-4) /* Integer overflow from size or index */
/**
* zbm_decompress - Decompress an LZBITMAP buffer
* @dest: destination buffer (may be NULL)
* @dest_size: size of the destination buffer
* @src: source buffer
* @src_size: size of the source buffer
* @out_len: on return, the length of the decompressed output
*
* May be called with a NULL destination buffer to retrieve the expected length
* of the decompressed data. Returns 0 on success, or a negative error code in
* case of failure.
*/
int zbm_decompress(void *dest, size_t dest_size, const void *src, size_t src_size, size_t *out_len);
/**
* zbm_compress - Compress a whole buffer with LZBITMAP
* @dest: destination buffer (may be NULL)
* @dest_size: size of the destination buffer
* @src: source buffer
* @src_size: size of the source buffer
* @out_len: on return, the length of the compressed output
*
* May be called with a NULL destination buffer to retrieve the maximum possible
* length of the compressed output. Returns 0 on success, or a negative error
* code in case of failure.
*
* This function just compresses the whole buffer sequentially, using a single
* thread. For speed, the caller should consider using zbm_compress_chunk()
* instead.
*/
int zbm_compress(void *dest, size_t dest_size, const void *src, size_t src_size, size_t *out_len);
#define ZBM_MAX_CHUNK_SIZE 0x800A
#define ZBM_LAST_CHUNK_SIZE 6
/*
* zbm_compress_chunk - Compress a single chunk in a buffer with LZBITMAP
* @dest: destination buffer
* @dest_size: size of the destination buffer
* @src: source buffer
* @src_size: size of the source buffer
* @index: which chunk from @src to compress
* @out_len: on return, the length of the compressed output
*
* Returns 0 on success, or a negative error code in case of failure.
*
* To compress a whole buffer, this function must be called repeatedly with the
* same value of @src and a sequentially increasing value of @index. The process
* concludes when @out_len returns ZBM_LAST_CHUNK_SIZE. The size of @dest must
* always be ZBM_MAX_CHUNK_SIZE or more.
*
* The advantage of this over zbm_compress() is that the caller can compress
* multiple chunks in parallel. For an example using pthreads, check the test
* code in test/test.c.
*/
int zbm_compress_chunk(void *dest, size_t dest_size, const void *src, size_t src_size, size_t index, size_t *out_len);
#endif /* _LIBZBITMAP_H */
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