C interface for libcurl.

go.c

#ifndef _GO_H_
#define _GO_H_

#include <curl/curl.h>

typedef struct {
	char *headers;
	char *body;
	CURL *handle;
	long int statuscode;
} GO_Response;

struct _GO_STRING {
	char *ptr;
	unsigned int size;
};

int _go_args_count(char *arg, ...) {
	va_list args;
	int i, size, count;
	char flag;
	
	va_start(args, arg);
	
	if (va_arg(args, char *) == NULL) return 0;
	
	va_end(args);
	
	size = strlen(arg);
	count = 1;
	flag = 0;
	
	if (size == 2) return 0;
	
	for (i=0; i<size; i++) {
		if ((i == 0 && arg[i] == '\"') || (i > 0 && arg[i] == '\"' && arg[i-1] != '\\')) {
			flag = !flag;
		}
		
		if (flag) continue;
		
		if (arg[i] == ',') count++;
	}
	
	return count;
}

static size_t _go_writefunction(void *data, size_t size, size_t nmemb, void *clientp) {
	struct _GO_STRING *str = (struct _GO_STRING*)clientp;
	char *aux;
	
	if (str->size == 0) {
		str->size = size * nmemb + 1;
		str->ptr = malloc(str->size);
		if (!str->ptr) return -1;
		strncpy(str->ptr, data, str->size);
	}
	else {
		str->size += size * nmemb;
		aux = realloc(str->ptr, str->size);
		if (!aux) {
			free(str->ptr);
			return -1;
		}
		str->ptr = aux;
		strncat(str->ptr, data, size * nmemb);
	}
	
	return size * nmemb;
}

void GO_free(GO_Response *response) {
	if (!response) return;
	free(response->headers);
	free(response->body);
	free(response);
}

GO_Response *GO(char *method, char *url, char *body, curl_off_t size, int args_count, ...) {
	int i;
	CURL *curl;
	CURLcode res;
	va_list args;
	GO_Response *response;
	struct curl_slist *aux, *chunk = NULL;
	struct _GO_STRING response_body = {0}, response_headers = {0};
	
	if (!method || !url) return NULL;
	
	va_start(args, args_count);
	
	for (i=0; i<args_count; i++) {
		aux = curl_slist_append(chunk, va_arg(args, char*));
		if (!aux) {
			if (chunk) curl_slist_free_all(chunk);
			return NULL;
		}
		chunk = aux;
	}
	
	va_end(args);
	
	curl_global_init(CURL_GLOBAL_ALL);
	curl = curl_easy_init();
	
	if (!curl) {
		curl_global_cleanup();
		return NULL;
	}
	
	if (strcmp(method, "WS") == 0 || strcmp(method, "WSS") == 0) {
		curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 2L);
		curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "GET");
	}
	else curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, method);
	
	curl_easy_setopt(curl, CURLOPT_URL, url);
	
	if (size == -1) {
		size = strlen(body);
	}
	
	if (size != 0) {
		curl_easy_setopt(curl, CURLOPT_POSTFIELDS, body);
		curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE_LARGE, size);
	}
	
	curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
	
	curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, _go_writefunction);
	curl_easy_setopt(curl, CURLOPT_HEADERDATA, &response_headers);	
	
	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, _go_writefunction);
	curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response_body);
	
	curl_easy_setopt(curl, CURLOPT_CAINFO , "cacert.pem");
	
	res = curl_easy_perform(curl);
	
	if (chunk) curl_slist_free_all(chunk);
	
	if (res != CURLE_OK) {
		curl_easy_cleanup(curl);
		curl_global_cleanup();
		return NULL;
	}
	
	if ((response = calloc(1, sizeof(GO_Response))) == NULL) return NULL;
	
	response->handle = curl;
	
	if (response_headers.size > 0) {
		response->headers = response_headers.ptr;
		response->headers[response_headers.size-1] = 0;
	}

	if (response_body.size > 0) {
		response->body = response_body.ptr;
		response->body[response_body.size-1] = 0;
	}
	
	curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response->statuscode);
	
	if (strcmp(method, "WS") == 0 || strcmp(method, "WSS") == 0) {
		return response;
	}
	
	curl_easy_cleanup(curl);
	curl_global_cleanup();

	return response;
}

#define GO(method, url, body, size, ...) GO(method, url, body, size, _go_args_count(#__VA_ARGS__, __VA_ARGS__), __VA_ARGS__)

#endif /* _GO_H_ */

/*///////////////////////////////////
	
		Testing:
		
///////////////////////////////////*/

int main(void) {
	
	GO_Response *r = GO("GET", "https://github.com/", "", -1, NULL);
	
	printf("Headers: %s\n\n", r->headers);
	printf("Body: %s\n\n", r->body);
	printf("Status Code: %i\n", (int)r->statuscode);
	
	GO_free(r);
	
	return 0;
}