ref: 6c26e2617c8cabdb8e05ca0f7180123a169b13a2
dir: /tools/lz/proto.h/
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdarg.h> #define NUM_COMPRESSORS 4 #define COMPRESSION_METHODS 96 /* sum of all values for the methods field in compressors */ #define MAX_FILE_SIZE 32768 #define SHORT_COMMAND_COUNT 32 #define MAX_COMMAND_COUNT 1024 #define LOOKBACK_LIMIT 128 /* highest negative valid count for a copy command */ #define LOOKAHEAD_LIMIT 3072 /* maximum lookahead distance for the first pass of multi-pass compression */ #define MULTIPASS_SKIP_THRESHOLD 64 #if __STDC_VERSION__ >= 201112L // <noreturn.h> forces "noreturn void", which is silly and redundant; this is simpler #define noreturn _Noreturn void #else #define noreturn void /* fallback */ #endif struct command { unsigned command: 3; // commands 0-6 as per compression spec; command 7 is used as a dummy placeholder unsigned count: 12; // always equals the uncompressed data length signed value: 17; // offset for commands 0 (into source) and 4-6 (into decompressed output); repeated bytes for commands 1-2 }; struct compressor { unsigned methods; const char * name; struct command * (* function) (const unsigned char *, const unsigned char *, unsigned short *, unsigned); }; struct options { const char * input; const char * output; unsigned method; // method to use, or >= COMPRESSION_METHODS to try them all unsigned char mode; // 0: compress, 1: compress to text, 2: uncompress, 3: dump commands as text unsigned char alignment; // 1 << value }; // global.c extern const struct compressor compressors[]; extern const unsigned char bit_flipping_table[]; extern char option_name_buffer[]; // main.c int main(int, char **); struct command * compress(const unsigned char *, unsigned short *, unsigned); // merging.c struct command * select_optimal_sequence(struct command **, const unsigned short *, unsigned short *); struct command * select_command_sequence(struct command **, const unsigned short *, int, unsigned short *); struct command * merge_command_sequences(const struct command *, unsigned short, const struct command *, unsigned short, unsigned short *); // mpcomp.c struct command * try_compress_multi_pass(const unsigned char *, const unsigned char *, unsigned short *, unsigned); struct command pick_command_for_pass(const unsigned char *, const unsigned char *, const unsigned char *, const short *, unsigned short, unsigned short, unsigned); struct command pick_repetition_for_pass(const unsigned char *, unsigned short, unsigned short, unsigned); struct command pick_copy_for_pass(const unsigned char *, const unsigned char *, const short *, unsigned char, unsigned short, unsigned short, unsigned); // nullcomp.c struct command * store_uncompressed(const unsigned char *, const unsigned char *, unsigned short *, unsigned); // options.c struct options get_options(int, char **); unsigned parse_numeric_option_argument(char ***, unsigned); int parse_compressor_option_argument(char ***); const char * get_argument_for_option(char ***, const char **); noreturn usage(const char *); noreturn list_compressors(void); // output.c void write_commands_to_textfile(const char *, const struct command *, unsigned, const unsigned char *, unsigned char); void write_commands_and_padding_to_textfile(const char *, const struct command *, unsigned, const unsigned char *, unsigned, unsigned); void write_command_to_textfile(FILE *, struct command, const unsigned char *); void write_commands_to_file(const char *, const struct command *, unsigned, const unsigned char *, unsigned char); void write_command_to_file(FILE *, struct command, const unsigned char *); void write_raw_data_to_file(const char *, const void *, unsigned); // packing.c void optimize(struct command *, unsigned short); void repack(struct command **, unsigned short *); // repcomp.c struct command * try_compress_repetitions(const unsigned char *, const unsigned char *, unsigned short *, unsigned); struct command find_repetition_at_position(const unsigned char *, unsigned short, unsigned short); // spcomp.c struct command * try_compress_single_pass(const unsigned char *, const unsigned char *, unsigned short *, unsigned); struct command find_best_copy(const unsigned char *, unsigned short, unsigned short, const unsigned char *, unsigned); unsigned short scan_forwards(const unsigned char *, unsigned short, const unsigned char *, unsigned short, short *); unsigned short scan_backwards(const unsigned char *, unsigned short, unsigned short, short *); struct command find_best_repetition(const unsigned char *, unsigned short, unsigned short); // uncomp.c struct command * get_commands_from_file(const unsigned char *, unsigned short * restrict, unsigned short * restrict); unsigned char * get_uncompressed_data(const struct command *, const unsigned char *, unsigned short *); // util.c noreturn error_exit(int, const char *, ...); unsigned char * read_file_into_buffer(const char *, unsigned short *); struct command pick_best_command(unsigned, struct command, ...); int is_better(struct command, struct command); short command_size(struct command); unsigned short compressed_length(const struct command *, unsigned short);