pokecrystal-board/tools/lz/util.c
aaaaaa123456789 2b7237e299
Match LZ compressed files (#724)
Replace lzcomp with new version and match all LZ compressed files
2020-05-23 13:30:04 -04:00

55 lines
1.8 KiB
C

#include "proto.h"
noreturn error_exit (int error_code, const char * error, ...) {
va_list ap;
va_start(ap, error);
fputs("error: ", stderr);
vfprintf(stderr, error, ap);
va_end(ap);
fputc('\n', stderr);
exit(error_code);
}
unsigned char * read_file_into_buffer (const char * file, unsigned short * size) {
FILE * fp = file ? fopen(file, "rb") : stdin;
if (!fp) error_exit(1, "could not open file %s for reading", file);
unsigned char * buf = malloc(MAX_FILE_SIZE + 1);
int rv = fread(buf, 1, MAX_FILE_SIZE + 1, fp);
if (file) fclose(fp);
if (rv < 0) error_exit(1, "could not read from file %s", file);
if (rv > MAX_FILE_SIZE) error_exit(1, "file %s is too big", file ? file : "<standard input>");
*size = rv;
return buf;
}
struct command pick_best_command (unsigned count, struct command command, ...) {
struct command result = command;
va_list ap;
va_start(ap, command);
while (-- count) {
command = va_arg(ap, struct command);
if (is_better(command, result)) result = command;
}
va_end(ap);
return result;
}
int is_better (struct command new, struct command old) {
if (new.command == 7) return 0;
if (old.command == 7) return 1;
short new_savings = new.count - command_size(new), old_savings = old.count - command_size(old);
return new_savings > old_savings;
}
short command_size (struct command command) {
short header_size = 1 + (command.count > SHORT_COMMAND_COUNT);
if (command.command & 4) return header_size + 1 + (command.value >= 0);
return header_size + command.command[(short []) {command.count, 1, 2, 0}];
}
unsigned short compressed_length (const struct command * commands, unsigned short count) {
unsigned short current, total = 0;
for (current = 0; current < count; current ++) if (commands[current].command != 7) total += command_size(commands[current]);
return total;
}