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-rw-r--r--tools/lz/proto.h107
1 files changed, 107 insertions, 0 deletions
diff --git a/tools/lz/proto.h b/tools/lz/proto.h
new file mode 100644
index 000000000..845774221
--- /dev/null
+++ b/tools/lz/proto.h
@@ -0,0 +1,107 @@
+#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);