/*
* Given a valid huffman mode, this function will generate the compression table that lists the codes for each
* of the ascii characters that the compression scheme uses. That table is placed into the pOutTable passed
* in by the caller.
*
* Table will have 256 entries and look like:
* 01001
* 001
* 0111
* ...
* 00001
*/
eFileCode GenerateTableAndCompressOrDecompress(eMode huffmanMode, const char *fileName)
{
eFileCode fileCode; // And error code which tells if the operation was successful or not.
FILE *pFile = fopen(fileName, "r"); // Open file for reading.
fileCode = FILE_SUCCESS;
// Check that file was successfully opened. If not, return an error code.
if (pFile == NULL)
{
return FILE_MISSING;
}
switch(huffmanMode)
{
case DECOMPRESS_MODE:
{
// If the file is a compressed huffman file, then use the get table for huff function to open it.
char huffmanEncodings[ENTRIES * ENTRY_LENGTH];
unsigned long long lengthOfFile =
huffmanEncodingsFromFile(pFile, huffmanEncodings);
huffResult resultArray[ENTRIES];
createHuffResultArrayFromFileEncodings(huffmanEncodings, resultArray);
huffNode huffmanTree[ENTRIES + ENTRIES - 1];
createDecodeTreeFromResultArray(resultArray, huffmanTree);
FILE *rle_file = xtmpfile();
writeCompressedFileToNonCompressedOutput(pFile, rle_file, lengthOfFile, &huffmanTree[0]);
rewind(rle_file);
int nameLength = strlen(fileName) - strlen(".hurl");
char newFileName[nameLength + 1];
strncpy(newFileName, fileName, nameLength);
newFileName[nameLength] = 0;
FILE *pNewFile = xfopen(newFileName, "w");
rle_decode(rle_file, pNewFile);
fclose(rle_file);
fclose(pNewFile);
break;
}
case TABLE_MODE_HURL:
{
// If we want a table and the file is .hurl, it may or may not be the same .hurl we want it to be.
// We'll try to treat it as a .hurl but if it's the wrong format, we will treat it like a generic
// file.
char huffmanEncodings[ENTRIES * ENTRY_LENGTH];
huffmanEncodingsFromFile(pFile, huffmanEncodings);
if (huffmanEncodings[0] != 0)
{
huffResult resultArray[ENTRIES];
createHuffResultArrayFromFileEncodings(huffmanEncodings, resultArray);
printHuffResultArray(resultArray);
}
else
{
// File was a .hurl, but internally format doesn't fit. Oh well, we can still generate a compression table.
// Maybe someone else in the world created their own .hurl file format. We need to handle that format.
fseek(pFile, 0, SEEK_SET);
// The frequency of occurrence of each character in the uncompressed file.
unsigned long long pFrequencies[ENTRIES];
memset(pFrequencies, 0, sizeof(pFrequencies));
if (GenerateFrequenciesForGeneric(pFile, pFrequencies) == FILE_SUCCESS)
{
huffResult resultArray[ENTRIES];
fileCode = GetTableForGeneric(pFrequencies, resultArray);
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
}
break;
}
case TABLE_MODE_GENERIC:
{
// If the file is not a .hurl, then generate frequencies and then a table for the file.
// The frequency of occurrence of each character in the uncompressed file.
unsigned long long pFrequencies[ENTRIES];
memset(pFrequencies, 0, sizeof(pFrequencies));
if (GenerateFrequenciesForGeneric(pFile, pFrequencies) == FILE_SUCCESS)
{
huffResult resultArray[ENTRIES];
fileCode = GetTableForGeneric(pFrequencies, resultArray);
printHuffResultArray(resultArray);
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
break;
}
case COMPRESS_MODE:
{
FILE *rle_file = xtmpfile();
rle_encode(pFile, rle_file);
rewind(rle_file);
unsigned long long pFrequencies[ENTRIES];
memset(pFrequencies, 0, sizeof(pFrequencies));
if (GenerateFrequenciesForGeneric(rle_file, pFrequencies) != FILE_SUCCESS)
{
fileCode = FILE_INVALID_FORMAT;
break;
}
huffResult resultArray[ENTRIES];
fileCode = GetTableForGeneric(pFrequencies, resultArray);
char newFileName[strlen(fileName) + 6];
strcpy(newFileName, fileName);
FILE *pNewFile = fopen(strcat(newFileName, ".hurl"), "w+");
if (pNewFile == NULL)
{
fileCode = FILE_INVALID_FORMAT;
break;
}
writeNonCompressedFileToCompressedOutput(rle_file, pNewFile, resultArray);
fclose(rle_file);
fclose(pNewFile);
break;
}
default:
{
// File must not be valid for the specified commandline options if we get this far.
fileCode = FILE_INVALID_FORMAT;
break;
}
}
fclose(pFile);
return fileCode;
}
/*
* Given a valid huffman mode, this function will generate the compression table that lists the codes for each
* of the ascii characters that the compression scheme uses. That table is placed into the pOutTable passed
* in by the caller.
*
* Table will have 256 entries and look like:
* 01001
* 001
* 0111
* ...
* 00001
*/
eFileCode GenerateTableAndCompressOrDecompress(eMode huffmanMode, char* fileName, huffResult* resultArray)
{
FILE* pFile;
FILE* pNewFile;
char* huffmanEncodings;
huffNode* huffmanTreeRootNode;
unsigned long long lengthOfFile = 0;
unsigned pFrequencies[ENTRIES] = {0}; // The frequency of occurrence of each character in the uncompressed file.
eFileCode fileCode; // And error code which tells if the operation was successful or not.
pFile = fopen(fileName, "r"); // Open file for reading.
fileCode = FILE_SUCCESS;
// Check that file was successfully opened. If not, return an error code.
if (pFile == NULL)
{
return FILE_MISSING;
}
switch(huffmanMode)
{
case DECOMPRESS_MODE:
// If the file is a compressed huffman file, then use the get table for huff function to open it.
huffmanEncodings = huffmanEncodingsFromFile(pFile, &lengthOfFile);
if (huffmanEncodings != NULL)
{
int nameLength = strlen(fileName) - strlen(".huff\0");
assert(nameLength > 0);
char* newFileName = calloc(nameLength + 1, sizeof(char));
strncpy(newFileName, fileName, nameLength);
pNewFile = fopen(strcat(newFileName, ".debug"), "w+");
if (pNewFile == NULL)
{
fileCode = FILE_INVALID_FORMAT;
}
else
{
resultArray = createHuffResultArrayFromFileEncodings(huffmanEncodings);
huffmanTreeRootNode = createDecodeTreeFromResultArray(resultArray);
writeCompressedFileToNonCompressedOutput(pFile, pNewFile, lengthOfFile, huffmanTreeRootNode);
fclose(pNewFile);
}
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
break;
case TABLE_MODE_HUFF:
// If we want a table and the file is .huff, it may or may not be the same .huff we want it to be.
// We'll try to treat it as a .huff but if it's the wrong format, we will treat it like a generic
// file.
huffmanEncodings = huffmanEncodingsFromFile(pFile, &lengthOfFile);
if (huffmanEncodings != NULL)
{
if (pNewFile == NULL)
{
fileCode = FILE_INVALID_FORMAT;
}
else
{
resultArray = createHuffResultArrayFromFileEncodings(huffmanEncodings);
}
}
else
{
// File was a .huff, but internally format doesn't fit. Oh well, we can still generate a compression table.
// Maybe someone else in the world created their own .huff file format. We need to handle that format.
fseek(pFile, 0, SEEK_SET);
if (GenerateFrequenciesForGeneric(pFile, pFrequencies) == FILE_SUCCESS)
{
fileCode = GetTableForGeneric(pFrequencies, &resultArray);
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
}
break;
case TABLE_MODE_GENERIC:
// If the file is not a .huff, then generate frequencies and then a table for the file.
if (GenerateFrequenciesForGeneric(pFile, pFrequencies) == FILE_SUCCESS)
{
fileCode = GetTableForGeneric(pFrequencies, &resultArray);
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
break;
case COMPRESS_MODE:
// If the file is not a .huff, then generate frequencies and then a table for the file.
if (GenerateFrequenciesForGeneric(pFile, pFrequencies) == FILE_SUCCESS)
{
fileCode = GetTableForGeneric(pFrequencies, &resultArray);
pNewFile = fopen(strcat(fileName, ".huff"), "w+");
if (pNewFile == NULL)
{
fileCode = FILE_INVALID_FORMAT;
}
else
{
writeNonCompressedFileToCompressedOutput(pFile, pNewFile, resultArray);
fclose(pNewFile);
}
}
else
{
fileCode = FILE_INVALID_FORMAT;
}
break;
default:
// File must not be valid for the specified commandline options if we get this far.
fileCode = FILE_INVALID_FORMAT;
break;
}
fclose(pFile);
return fileCode;
}