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/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
* block_processor.h
*
* Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
*/
#ifndef BLOCK_PROCESSOR_H
#define BLOCK_PROCESSOR_H
#include "config.h"
#include "compress.h"
enum {
/* only calculate checksum, do NOT compress the data */
BLK_DONT_COMPRESS = 0x0001,
/* set by compressor worker if the block was actually compressed */
BLK_IS_COMPRESSED = 0x0002,
/* do not calculate block checksum */
BLK_DONT_CHECKSUM = 0x0004,
/* set by compressor worker if compression failed */
BLK_COMPRESS_ERROR = 0x0008,
/* first user setable block flag */
BLK_USER = 0x0080
};
typedef struct block_t {
/* used internally, ignored and overwritten when enqueueing blocks */
struct block_t *next;
uint32_t sequence_number;
/* Size of the data area */
uint32_t size;
/* checksum of the input data */
uint32_t checksum;
/* user settable file block index */
uint32_t index;
/* user pointer associated with the block */
void *user;
/* user settable flag field */
uint32_t flags;
/* raw data to be processed */
uint8_t data[];
} block_t;
typedef struct block_processor_t block_processor_t;
/*
Gets called for each processed block. May be called from a different thread
than the one that calls enqueue, but only from one thread at a time.
Guaranteed to be called on blocks in the order that they are submitted
to enqueue.
A non-zero return value is interpreted as fatal error.
*/
typedef int (*block_cb)(void *user, block_t *blk);
block_processor_t *block_processor_create(size_t max_block_size,
compressor_t *cmp,
unsigned int num_workers,
void *user,
block_cb callback);
void block_processor_destroy(block_processor_t *proc);
/*
Add a block to be processed. Returns non-zero on error and prints a message
to stderr.
The function takes over ownership of the submitted block. It is freed with
a after processing and calling the block callback.
Even on failure, the workers may still be running and
block_processor_finish must be called before cleaning up.
*/
int block_processor_enqueue(block_processor_t *proc, block_t *block);
/*
Wait for the compressor workers to finish. Returns zero on success, non-zero
if an internal error occoured or one of the block callbacks returned a
non-zero value.
*/
int block_processor_finish(block_processor_t *proc);
/*
Convenience function to create a block structure and optionally fill it with
content.
filename is used for printing error messages. If fd is a valid file
descriptor (>= 0), the function attempts to populate the payload data
from the input file.
*/
block_t *create_block(const char *filename, int fd, size_t size,
void *user, uint32_t flags);
/*
Convenience function to process a data block. Returns 0 on success,
prints to stderr on failure.
*/
int process_block(block_t *block, compressor_t *cmp,
uint8_t *scratch, size_t scratch_size);
#endif /* BLOCK_PROCESSOR_H */
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