Making Requests

Collaboration diagram for Making Requests:

Functions
long	curl_download_to_file (const char *url, char *filename)
	Really simple document retrieval to file.
long	curl_download_to_memory (const char *url, size_t *returned_length, char **returned_data, struct ast_variable **headers)
	Really simple document retrieval to memory.
long	curler (const char *url, int request_timeout, struct curl_write_data *write_data, struct curl_header_data *header_data, struct curl_open_socket_data *open_socket_data)
	Perform a curl request.

Detailed Description

Function Documentation

curl_download_to_file()

long curl_download_to_file	(	const char *	url,
		char *	filename
	)

Really simple document retrieval to file.

Parameters

url	The URL to retrieve.
filename	The filename to save it to.

Return values

An	HTTP response code.
-1	for internal error.

Definition at line 321 of file curl_utils.c.

{
    FILE *fp = NULL;
    long rc = 0;
    struct curl_write_data data = {
        .debug_info = ast_strdup(url),
    };
 
    if (ast_strlen_zero(url) || ast_strlen_zero(filename)) {
        ast_log(LOG_ERROR,"url or filename was NULL\n");
        return -1;
    }
    data.output = fopen(filename, "w");
    if (!fp) {
        ast_log(LOG_ERROR,"Unable to open file '%s': %s\n", filename,
            strerror(errno));
        return -1;
    }
    rc = curler(url, 0, &data,  NULL, NULL);
    fclose(data.output);
    ast_free(data.debug_info);
    return rc;
}

References ast_free, ast_log, ast_strdup, ast_strlen_zero(), curler(), curl_write_data::debug_info, errno, LOG_ERROR, NULL, curl_write_data::output, and url.

curl_download_to_memory()

long curl_download_to_memory	(	const char *	url,
		size_t *	returned_length,
		char **	returned_data,
		struct ast_variable **	headers
	)

Really simple document retrieval to memory.

Parameters

url	The URL to retrieve
returned_length	Pointer to a size_t to hold document length.
returned_data	Pointer to a buffer which will be updated to point to the data. Must be freed with ast_std_free() after use.
headers	Pointer to an ast_variable * that will contain the response headers. Must be freed with ast_variables_destroy() Set to NULL if you don't need the headers.

Return values

An	HTTP response code.
-1	for internal error.

Definition at line 300 of file curl_utils.c.

{
    struct curl_write_data data = {
        .debug_info = ast_strdupa(url),
    };
    struct curl_header_data hdata = {
        .debug_info = ast_strdupa(url),
    };
 
    long rc = curler(url, 0, &data, headers ? &hdata : NULL, NULL);
 
    *returned_length = data.stream_bytes_downloaded;
    *returned_data = data.stream_buffer;
    if (headers) {
        *headers = hdata.headers;
    }
 
    return rc;
}

References ast_strdupa, curler(), curl_header_data::debug_info, curl_write_data::debug_info, curl_header_data::headers, NULL, curl_write_data::stream_buffer, curl_write_data::stream_bytes_downloaded, and url.

Referenced by as_check_common_config().

curler()

long curler	(	const char *	url,
		int	request_timeout,
		struct curl_write_data *	write_data,
		struct curl_header_data *	header_data,
		struct curl_open_socket_data *	open_socket_data
	)

Perform a curl request.

Parameters

url	The URL to request.
request_timeout	If > 0, timeout after this number of seconds.
curl_write_data	A pointer to a curl_write_data structure. If curl_write_data.output is NULL, open_memstream will be called to provide one and the resulting data will be available in curl_write_data.stream_buffer with the number of bytes retrieved in curl_write_data.stream_bytes_downloaded. You must free curl_write_data.stream_buffer yourself with ast_std_free() when you no longer need it.
curl_header_data	A pointer to a ast_curl_header_data structure. The headers read will be in the curl_header_data.headers ast_variable list which you must free with ast_variables_destroy() when you're done with them.
curl_open_socket_data	A pointer to an curl_open_socket_data structure or NULL if you don't need it.

Return values

An	HTTP response code.
-1	for internal error.

Definition at line 232 of file curl_utils.c.

{
    RAII_VAR(CURL *, curl, NULL, curl_easy_cleanup);
    long http_code = 0;
    CURLcode rc;
 
    SCOPE_ENTER(1, "'%s': Retrieving\n", url);
 
    if (ast_strlen_zero(url)) {
        SCOPE_EXIT_LOG_RTN_VALUE(500, LOG_ERROR, "'missing': url is missing\n");
    }
 
    if (!write_data) {
        SCOPE_EXIT_LOG_RTN_VALUE(500, LOG_ERROR, "'%s': Either wite_cb and write_data are missing\n", url);
    }
 
    curl = curl_easy_init();
    if (!curl) {
        SCOPE_EXIT_LOG_RTN_VALUE(-1, LOG_ERROR, "'%s': Failed to set up CURL instance\n", url);
    }
 
    curl_easy_setopt(curl, CURLOPT_URL, url);
    if (request_timeout) {
        curl_easy_setopt(curl, CURLOPT_TIMEOUT, request_timeout);
    }
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_write_cb);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, write_data);
 
    if (header_data) {
        curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, curl_header_cb);
        curl_easy_setopt(curl, CURLOPT_HEADERDATA, header_data);
    }
 
    curl_easy_setopt(curl, CURLOPT_USERAGENT, AST_CURL_USER_AGENT);
 
    if (open_socket_data) {
        curl_easy_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, curl_open_socket_cb);
        curl_easy_setopt(curl, CURLOPT_OPENSOCKETDATA, open_socket_data);
    }
 
    curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
    /*
     * ATIS-1000074 specifically says to NOT follow redirections.
     */
    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 0);
 
    rc = curl_easy_perform(curl);
    if (rc != CURLE_OK) {
        char *err = ast_strdupa(curl_easy_strerror(rc));
        SCOPE_EXIT_LOG_RTN_VALUE(-1, LOG_ERROR, "'%s': %s\n", url, err);
    }
 
    fflush(write_data->output);
    if (write_data->_internal_memstream) {
        fclose(write_data->output);
        write_data->output = NULL;
    }
 
    curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
    curl_easy_cleanup(curl);
    curl = NULL;
 
    SCOPE_EXIT_RTN_VALUE(http_code, "'%s': Done: %ld\n", url, http_code);
}

References curl_write_data::_internal_memstream, AST_CURL_USER_AGENT, ast_strdupa, ast_strlen_zero(), curl_header_cb(), curl_open_socket_cb(), curl_write_cb(), LOG_ERROR, NULL, curl_write_data::output, RAII_VAR, SCOPE_ENTER, SCOPE_EXIT_LOG_RTN_VALUE, SCOPE_EXIT_RTN_VALUE, and url.

Referenced by curl_download_to_file(), curl_download_to_memory(), and retrieve_cert_from_url().