CRC32 C realization – does not work

typedef struct {
 unsigned short xor;
} xor_context;
void crc32_init(crc32_context *context) {
 context->crc = 0xFFFFFFFF;
}
void crc32_update(crc32_context *context, unsigned char byte) {
 uint32_t crc, mask ;

 crc = context->crc;
 crc = crc ^ byte;
 for (int j = 7; j >= 0; j--) {// Do eight times.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask);
 }
 context->crc = ~ crc;
}

unsigned int crc32b(unsigned char *message) {
 int i, j ;
 unsigned int byte, crc, mask;

 i = 0;
 crc = 0xFFFFFFFF;
 while (message[i] != 0) {
 byte = message[i]; // Get next byte.
 crc = crc ^ byte;
 for (j = 7; j >= 0; j--) {// Do eight ti mes.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask);
 }
 i = i + 1;< br /> }
 return ~crc;
}

 //typedef struct {
// unsigned short xor;
//} xor_context;//--> Not sure what part this plays in the code!

void crc32_init( crc32_context *context) {
 context->crc = 0xFFFFFFFF;
}

void crc32_update(crc32_context *context, unsigned char byte) {
 uint32_t crc, mask; 

 crc = context->crc;
 crc = crc ^ byte;
 for (int j = 7; j >= 0; j--) {// Do eight times.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask);
 }
 //context->crc = ~crc; //<-- Don't perform for every byte.
 context->crc = crc; //EDIT: Forgot this!
}

//Completes the check.
uint32_t crc32_complete(crc32_context *context){
 return ~context->crc;
)

I found this CRC32 implementation on the internet and changed it a bit, but I can’t get it to work. Initialize it and update it on every byte I get from the input, but the hash I get is not what it should be…

typedef struct {< br /> unsigned short xor;
} xor_context;
void crc32_init(crc32_context *context) {
 context->crc = 0xFFFFFFFF;
}
void crc32_update(crc32_context *context, unsigned char byte) {
 uint32_t crc, mask;

 crc = context->crc;
 crc = crc ^ byte;
 for (int j = 7; j >= 0; j--) {// Do eight times.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask) ;
 }
 context->crc = ~crc;
}

This is original

unsigned int crc32b(unsigned char *message) {
 int i, j;
 unsigned int byte, crc, mask;

 i = 0;
 crc = 0xFFFFFFFF;< br /> while (message[i] != 0) {
 byte = message[i]; // Get next byte.
 crc = crc ^ byte;
 for (j = 7 ; j >= 0; j--) { // Do eight times.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask);
 }
 i = i + 1;
 }
 return ~crc;
}

//typedef struct {
// unsigned short xor;
//} xor_context;//--> Not sure what part this plays in the code!

void crc32_init(crc32_context *context) {
 context->crc = 0xFFFFFFFF;
}
void crc32_update(crc32_context *context, unsigned char byte) {
 uint32_t crc, mask;
 crc = context->crc;
 crc = crc ^ byte;
 for (int j = 7; j >= 0; j--) {// Do eight times.
 mask = -(crc & 1);
 crc = (crc >> 1) ^ (0xEDB88320 & mask);
 }
 //context->crc = ~crc; //<-- Don't perform for every byte.
 context->crc = crc; //EDIT: Forgot this!
}
//Completes the check.
uint32_t crc32_complete(crc32_context *context){
 return ~context->crc;
}