ref: 0a1b6b4f15da58f47b7a6fcf3b650b8e5c3a7b53
dir: /tools/lz/uncomp.c/
#include "proto.h" struct command * get_commands_from_file (const unsigned char * data, unsigned short * restrict size, unsigned short * restrict slack) { struct command * result = malloc(*size * sizeof(struct command)); unsigned short remaining = *size; struct command * current = result; const unsigned char * rp = data; while (1) { if (!(remaining --)) goto error; current -> command = *rp >> 5; current -> count = *(rp ++) & 31; if (current -> command == 7) { current -> command = current -> count >> 2; current -> count = (current -> count & 3) << 8; if (current -> command == 7) { // long commands inside long commands are not allowed, but if the count is 0x300 here, it means that the original byte was 0xff if (current -> count == 0x300) break; goto error; } if (!(remaining --)) goto error; current -> count |= *(rp ++); } current -> count ++; switch (current -> command) { case 0: if (remaining <= current -> count) goto error; current -> value = rp - data; rp += current -> count; remaining -= current -> count; case 3: break; case 1: case 2: { unsigned char p; if (remaining <= current -> command) goto error; current -> value = 0; for (p = 0; p < current -> command; p ++) current -> value |= *(rp ++) << (p << 3); remaining -= current -> command; } break; default: if (!(remaining --)) goto error; if ((current -> value = *(rp ++)) & 128) current -> value = 127 - current -> value; else { if (!(remaining --)) goto error; current -> value = (current -> value << 8) | *(rp ++); } } current ++; } if (slack) *slack = *size - (rp - data); *size = current - result; return realloc(result, (*size ? *size : 1) * sizeof(struct command)); error: free(result); return NULL; } unsigned char * get_uncompressed_data (const struct command * commands, const unsigned char * compressed, unsigned short * size) { const struct command * limit = commands + *size; unsigned char * result = malloc(MAX_FILE_SIZE + MAX_COMMAND_COUNT); unsigned char * current = result; unsigned short p; for (; commands < limit; commands ++) { switch (commands -> command) { case 0: memcpy(current, compressed + commands -> value, commands -> count); current += commands -> count; break; case 1: case 2: for (p = 0; p < commands -> count; p ++) *(current ++) = commands -> value >> ((p % commands -> command) << 3); break; case 3: memset(current, 0, commands -> count); current += commands -> count; break; default: { const unsigned char * ref = ((commands -> value < 0) ? current : result) + commands -> value; for (p = 0; p < commands -> count; p ++) { current[p] = ref[(commands -> command == 6) ? -(int) p : p]; if (commands -> command == 5) current[p] = bit_flipping_table[current[p]]; } current += commands -> count; } } if ((current - result) > MAX_FILE_SIZE) { free(result); return NULL; } } *size = current - result; return realloc(result, *size ? *size : 1); }