/******************************************************************************
 * 
 *  Title  : hexToBinFileConverison.c 
 *  Version 0.0, 20 October 2000,
 *   
 *  Description: This program converts hex text file (serial byte stream) into binary file.
 *  Input: Hex text file fileName.hex
 *  Output: Binary file fileName.bin
 *  Note: The conversion ends when input character is not hex number.
 * 
 *  Author: Lukas Tomasek, tomasekl@fzu.cz
 *
 ******************************************************************************/

/******************************************************************************
 *                              Header files                                  *
 ******************************************************************************/
 
#include <ansi_c.h>
#include <utility.h>   

/******************************************************************************
 *                               Definitions                                  *
 ******************************************************************************/
 
#define NOT_VALID_HEX_NUMBER (-1)
#define SUCCESS               (0)

/******************************************************************************
 *                        Static Function Declarations                        *
 ******************************************************************************/

static int halfByteConversionHexToBin(char hexValue, unsigned char *binValue);

/******************************************************************************
 *                              		Main 		                          *
 ******************************************************************************/

int main(int argc, char *argv[]){

	FILE *hexFileHandle;
	FILE *binFileHandle;
	size_t bytesRead;
	char errorMessage[200];
	int status;
	long hexFileSize, i;
	char hexFileName[300];
	char binFileName[300];
	char directory[300];
	int hexValue;
	unsigned char binValue;
	unsigned char convertValue;
	int length, dirLength;

	memset(binFileName, 0, 300);
	memset(hexFileName, 0, 300);
	strcpy(hexFileName,argv[1]); /* get input hex file name (*.hex) */
    printf("%s\n", hexFileName);

	/* create binary file name (*.bin) */	  
	length=strlen(hexFileName)-4;
	strncpy(binFileName, hexFileName, length);
	
	strcat(binFileName,".bin");
	printf("%s\n", binFileName);
	
	hexFileHandle = fopen (hexFileName, "r"); /* open text file for read */
	binFileHandle = fopen (binFileName, "wb"); /* open binary file for write */        

	status=GetFileSize(hexFileName, &hexFileSize);
	printf("%d\n",hexFileSize);

	for(i=0;i<hexFileSize;i+=2){
		hexValue=fgetc(hexFileHandle);
		if(halfByteConversionHexToBin(hexValue, &binValue)!=SUCCESS){
			break;  /* non hex character->end of conversion, not error! */
		};
		convertValue=binValue<<4;
		hexValue=fgetc(hexFileHandle);
		if(halfByteConversionHexToBin(hexValue, &binValue)!=SUCCESS){
			break;  /* non hex character->end of conversion, not error! */  
		};
		convertValue+=binValue;
		fprintf(binFileHandle,"%c", convertValue);

	}	

	/* close files */
	status=fclose(hexFileHandle);
	status=fclose(binFileHandle);
	
	printf("----- PRESS ANY KEY -------");
	getchar();
	
	return(0);
}

/******************************************************************************
 *                              Static functions                              *
 ******************************************************************************/

/*=============================================================================
 *                           halfByteConversionHexToBin()
 *=============================================================================
 *
 *  Converts one hex character (range 0 to F) from input to output binary value
 *
 */

static int halfByteConversionHexToBin(char hexValue, unsigned char *binValue){

	if((hexValue>='0')&&(hexValue<='9')){
		*binValue=(unsigned char)(hexValue-'0');
	}else{
		if((hexValue>='A')&&(hexValue<='F')){
			*binValue=(unsigned char)(hexValue-'A'+10);
		}else{
			if((hexValue>='a')&&(hexValue<='f')){
				*binValue=(unsigned char)(hexValue-'a'+10);
			}else{
				return(NOT_VALID_HEX_NUMBER); /* input character is not valid hex number */
			}
		}
	}
	return(SUCCESS);
}

/******************************************************************************/