1 /***************************************************************************
3 * Project ___| | | | _ \| |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
8 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ***************************************************************************/
23 * An example demonstrating how an application can pass in a custom
24 * socket to libcurl to use. This example also handles the connect itself.
30 #include <curl/curl.h>
36 #define close closesocket
38 #include <sys/types.h> /* socket types */
39 #include <sys/socket.h> /* socket definitions */
40 #include <netinet/in.h>
41 #include <arpa/inet.h> /* inet (3) functions */
42 #include <unistd.h> /* misc. Unix functions */
47 /* The IP address and port number to connect to */
48 #define IPADDR "127.0.0.1"
52 #define INADDR_NONE 0xffffffff
55 static size_t write_data(void *ptr, size_t size, size_t nmemb, void *stream)
57 size_t written = fwrite(ptr, size, nmemb, (FILE *)stream);
61 static int closecb(void *clientp, curl_socket_t item)
64 printf("libcurl wants to close %d now\n", (int)item);
68 static curl_socket_t opensocket(void *clientp,
70 struct curl_sockaddr *address)
75 sockfd = *(curl_socket_t *)clientp;
76 /* the actual externally set socket is passed in via the OPENSOCKETDATA
81 static int sockopt_callback(void *clientp, curl_socket_t curlfd,
87 /* This return code was added in libcurl 7.21.5 */
88 return CURL_SOCKOPT_ALREADY_CONNECTED;
95 struct sockaddr_in servaddr; /* socket address structure */
100 int initwsa = WSAStartup(MAKEWORD(2, 0), &wsaData);
102 printf("WSAStartup failed: %d\n", initwsa);
107 curl = curl_easy_init();
110 * Note that libcurl will internally think that you connect to the host
111 * and port that you specify in the URL option.
113 curl_easy_setopt(curl, CURLOPT_URL, "http://99.99.99.99:9999");
115 /* Create the socket "manually" */
116 sockfd = socket(AF_INET, SOCK_STREAM, 0);
117 if(sockfd == CURL_SOCKET_BAD) {
118 printf("Error creating listening socket.\n");
122 memset(&servaddr, 0, sizeof(servaddr));
123 servaddr.sin_family = AF_INET;
124 servaddr.sin_port = htons(PORTNUM);
126 servaddr.sin_addr.s_addr = inet_addr(IPADDR);
127 if(INADDR_NONE == servaddr.sin_addr.s_addr)
130 if(connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) ==
133 printf("client error: connect: %s\n", strerror(errno));
137 /* no progress meter please */
138 curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 1L);
140 /* send all data to this function */
141 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
143 /* call this function to get a socket */
144 curl_easy_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, opensocket);
145 curl_easy_setopt(curl, CURLOPT_OPENSOCKETDATA, &sockfd);
147 /* call this function to close sockets */
148 curl_easy_setopt(curl, CURLOPT_CLOSESOCKETFUNCTION, closecb);
149 curl_easy_setopt(curl, CURLOPT_CLOSESOCKETDATA, &sockfd);
151 /* call this function to set options for the socket */
152 curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
154 curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
156 res = curl_easy_perform(curl);
158 curl_easy_cleanup(curl);
161 printf("libcurl error: %d\n", res);