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#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "lzp.h"
static char* lcase(char* text) {
int i;
for(i=0; text[i]!=0x00; i++)
text[i] = tolower(text[i]);
return(text);
}
int lzpSearchFile(const char* fileName, const LZP_HEAD* lzpack) {
int i;
char searchName[16];
char compareName[16];
LZP_FILE* fileEntry;
strcpy(searchName, fileName);
lcase(searchName);
fileEntry = (LZP_FILE*)(((const char*)lzpack)+sizeof(LZP_HEAD));
for(i=0; i<(lzpack->numFiles); i++) {
strcpy(compareName, fileEntry[i].fileName);
lcase(compareName);
if (strcmp(searchName, compareName) == 0)
return(i);
}
return(LZP_ERR_NOTFOUND);
}
const LZP_FILE* lzpFileEntry(const LZP_HEAD* lzpack, int fileNum) {
if (strncmp("LZP", lzpack->id, 3) != 0)
return(NULL);
if ((fileNum < 0) || (fileNum > (lzpack->numFiles-1)))
return(NULL);
return &((LZP_FILE*)(((const char*)lzpack)+sizeof(LZP_HEAD)))[fileNum];
}
int lzpFileSize(const LZP_HEAD* lzpack, int fileNum) {
if (strncmp("LZP", lzpack->id, 3) != 0)
return 0;
if ((fileNum < 0) || (fileNum > (lzpack->numFiles-1)))
return 0;
return ((LZP_FILE*)(((const char*)lzpack)+sizeof(LZP_HEAD)))[fileNum].fileSize;
}
int lzpUnpackFile(void* buff, const LZP_HEAD* lzpack, int fileNum) {
LZP_FILE* fileEntry = &((LZP_FILE*)(((const char*)lzpack)+sizeof(LZP_HEAD)))[fileNum];
int unpackedSize;
// Check ID header
if (strncmp("LZP", lzpack->id, 3) != 0)
return(LZP_ERR_INVALID_PACK);
// Do a CRC16 check of the compressed data's integrity
if (lzCRC32(((const char*)lzpack)+fileEntry->offset, fileEntry->packedSize, LZP_CRC32_REMAINDER) != fileEntry->crc)
return(LZP_ERR_CRC_MISMATCH);
// Decompress data to the specified address
unpackedSize = lzDecompress(buff, ((const char*)lzpack)+fileEntry->offset, fileEntry->packedSize);
if (unpackedSize < 0)
return(unpackedSize);
return(unpackedSize);
}
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