int uleb128ToUint(FILE *fp, int *from) {
setOffset(fp, *from);
int *bits, *temp = (int *)malloc(sizeof(int) * 8);
int count = 1, i, j, a, y, z = 0, somma = 0;
//aumenta il count finchè trova byte con il bit più significativo settato a 1
while((bits = byteToBits(fgetc(fp)))[7] == 1) {
count++;
}
int **converted = (int **)malloc(sizeof(int *) * count);
fseek(fp, *from, 0);
//aggiorno il puntatore al prossimo byte per una lettura futura
*from += count;
//inizializzo l'array "converted"
for(i = 0; i < count; i++) {
converted[i] = (int *)malloc(sizeof(int) * 7);
}
//inserisce nell'array "converted" tutti i byte che compongono il numero
for(i = 0; i < count; i++) {
temp = byteToBits(fgetc(fp));
for(j = 0; j < 7; j++) {
converted[i][j] = temp[j];
}
}
//rovescia l'array (little-endian)
for(i = 0; i < count; i++) {
y = 6;
for(j = 0; j < 4; j++) {
a = converted[i][j];
converted[i][j] = converted[i][y];
converted[i][y--] = a;
}
}
//calcola il numero
for(i = 0; i < count; i++) {
for(j = 6; j >= 0; j--) {
if(converted[i][j] == 1) {
somma += potenza(2, z);
}
z++;
}
}
return somma;
}
void refillBits(char bits[16], FILE *fp){
//memset(&bits,0,sizeof(bits));
//TODO DECODE mode?
unsigned char next1, next2, next3;
next1 = (unsigned char)fgetc(fp);
next2 = (unsigned char)fgetc(fp);
//next3 = (unsigned char)fgetc(fp);
//printf("NextChars: %d %d %d\n",next1,next2,next3);
byteToBits(bits,next1,next2);
fseek(fp,-1,SEEK_CUR);
//if(next3 == EOF){
// return 1;
//}else{
// return 0;
//}
}
int main(int argc, char *argv[])
{
if(argc == 2){ //argumente ueberpruefen
//char mode;
/*unsigned char divident[2]; //CRC16 = x 16 + x 15 + x 2 + 1
// 1100 0000 0000 0101
divident[0] = 192;
divident[1] = 5;*/
char divisor[16];
byteToBits(divisor,(unsigned char)192,(unsigned char)5);
//DEBUG
dbgPrintBits(divisor);
FILE *fp = fopen(argv[1],"r");
if(fp != NULL){
//.crc endung? --> letzte 4 Zeichen auf .crc ueberpruefen
/*for(int i = 0; i<10;i++){printf("%c %d\n",argv[1][i],argv[1][i]); fflush(stdout); }*/ //string terminiert bei 0 - wer haette es gedacht..
int len = 0;
while(argv[1][len] != 0){
len++;
}
if(
argv[1][len-4] == '.' &&
argv[1][len-3] == 'c' &&
argv[1][len-2] == 'r' &&
argv[1][len-1] == 'c'
){
//check checksum
MODE = DECODE;
}else{
//create checksum
//dateiinhalt um 2 leere (16x0) bytes erweitern
//immer 2 bytes einlesen und durch divident teilen (mod 2) / bzw xor
MODE = ENCODE;
}
printf("MODE: %d\n\n",MODE);
//neuer dateiname
char filename[128];
memset(filename,0,sizeof filename);
//filename = argv[1];
int i = 0;
while(argv[1][i] != 0 && i < 123){
filename[i] = argv[1][i];
i++;
}
if(MODE == 1){ //ENCODE
filename[i] = '.';
filename[i+1] = 'c';
filename[i+2] = 'r';
filename[i+3] = 'c';
}else{ //DECODE
filename[i] = 0;
}
//DEBUG
printf("filename %s\n\n",filename);
char remain[2];
//create file
FILE *outputf = fopen(filename,"w+");
if(outputf != NULL){
//write file
if(MODE){
//ENCODE : complete
char buffer;
while((buffer= fgetc(fp)) != EOF){
fputc(buffer,outputf);
}
}else{
//DECODE : all except the last 2 bytes
char buffer;
while ((buffer = fgetc(fp)) != EOF){
fputc(buffer,outputf);
remain[0] = fgetc(fp);
remain[1] = fgetc(fp);
buffer = fgetc(fp);
if(buffer == EOF){
break;
}else{
fseek(fp,-3,SEEK_CUR);
}
}
}
//DEBUG
printf("File copied\n");
//fseek
if(fseek(outputf,0,SEEK_SET)!=0){
printf("error seeking in file\n");
}
return 0;
char bits[16], queue[16];
refillBits(bits,outputf);
refillBits(queue,outputf);
//DEBUG
printf("Filled bits: \n");
dbgPrintBits(bits);
dbgPrintBits(queue);
shiftBits(bits,queue,outputf);
//DEBUG
printf("shifted bits: \n");
dbgPrintBits(bits);
dbgPrintBits(queue);
//return 0;
//algorithm
while(queue[0] != -1){
xor(bits,divisor);
shiftBits(bits,queue,outputf);
}
if(MODE){
//ENCODE --> add remainder to file
int remIndicator = 0;
int c = 128;
for(int i = 0;i<16;i++){
//DEBUG
//printf("i = %d , byte: %d, c: %d\n",i,helpbyte,c);
if(bits[i] == 1){
//DEBUG
//printf("Byte: %d, C: %d\n",helpbyte,c);
remain[remIndicator] += c;
}
if(c == 1){
if(remIndicator == 1){
break;
}
//DEBUG
//printf("RESET c = %d byte = %d\n",c,helpbyte);
c = 128;
remIndicator = 1;
}else{
//DEBUG
//printf("c: %d :/ 2 = \n",c);
c /= 2;
//printf("%d\n",c);
}
}
fputc(remain[0],outputf);
fputc(remain[1],outputf);
}else{
//DECODE check remainder
char checksum[16];
byteToBits(checksum,remain[0],remain[1]);
for(int z = 0; z<5;z++){
if(checksum[i] != bits[i]){
printf("CRC-Checksum stimmt nicht mit dem Inhalt ueberein!\n");
fclose(outputf);
remove(filename);
return 0;
}
}
}
//printf("EOF: %d %d\n",EOF,(unsigned char)EOF);
//printf("asci 10: %c\n",10);
fclose(fp);
fclose(outputf);
}else{
printf("Could not create File %s\n",filename);
}
}else{
printf("File not found\n");
}
}else{
printf("usage: %s <filename>\n",argv[0]);
}
}