Tokenize HTTP server response

[maganese187]

I am writing a simple but secure HTTP/1.0 client, for an assignment. The client should send a GET request to some server, and parse the server response into tokens, such as:

Initial line
Last-Modified:
Content-Type
Body:

I've found much documentation about socket programming, but nothing about how to properly tokenize the server response. Can someone point me in the right direction. This is the only way I could get things to somewhat work:

int clientResponse(int socket, char *version, char *code, char *message, char *server, char *lastModified, char *date, char *contentType, char *contentLength, char *body){
	char buf[MAX_FILE_SIZE];	// buffer to hold the incoming socket message
	char *ptrPosition;			// pointer used for seeking
	int nr=0;					// number of bytes read from socket
	int numScan=0;				// number of bytes parsed in buffer
	int numTokens=0;			// number of tokens found
	char *headerName;			// temp buffer for header field-name
	char *headerValue;			// temp buffer for header field-value

	// get message
	if((nr = getMessage(socket, buf, MAX_FILE_SIZE)) <= 0){
		return -1;
	}
	
	// get starting position of message
	ptrPosition = buf;

	if((headerName = malloc(BUF_SIZE)) == NULL){
		return -2;	
	}
	if((headerValue = malloc(BUF_SIZE)) == NULL){
		return -2;
	}

	// tokenize initial line
	if((numTokens = sscanf(ptrPosition, "%s %s %255[^\r\n]\r\n%n", version, code, message, &numScan)) != 3){
		return -3;
	}

	// move pointer position
	ptrPosition += numScan;

	// tokenize headers
	while((numTokens = sscanf(ptrPosition, "%255[^:]: %255[^\r\n]\r\n%n", headerName, headerValue, &numScan)) == 2){
		// check for body
		if(headerName[0] == '<'){
			strcpy(body, ptrPosition);
			break;
		}

		// move position
		ptrPosition += numScan;

		// set appropriate header token
		if(strcmp(headerName, "Date") == 0){
			strcpy(date, headerValue);
		}
		if(strcmp(headerName, "Server") == 0){
			strcpy(server, headerValue);
		}
		if(strcmp(headerName, "Last-Modified") == 0){
			strcpy(lastModified, headerValue);
		}
		if(strcmp(headerName, "Content-Length") == 0){
			strcpy(contentLength, headerValue);
		}
		if(strcmp(headerName, "Content-Type") == 0){
			strcpy(contentType, headerValue);
		}

	}

	// deallocate memory
	free(headerName);
	free(headerValue);

	return nr;
}

[laserlight]

Moved to Networking/Device Communication forum.

[Snafuist]

The first occurrence of the character ":" separates key from value in the header of HTTP responses. Find that character using strchr() and mark its position. Everything up to the marker is the key, marker + 2 (trailing whitespace) is the value.

Greets,
Philip

PS: on a general note, your function above is trying to do too much stuff at a time: get response, tokenize response, parse tokens. Each of these steps deserves its own function.