rtsp.c: new example

Code from
http://code.google.com/p/rtsprequest/source/browse/trunk/rtsprequest.cpp

docs/examples/rtsp.c

+/*
+ * Copyright (c) 2011, Jim Hollinger
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Jim Hollinger nor the names of its contributors
+ *     may be used to endorse or promote products derived from this
+ *     software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if defined (WIN32)
+#  include <conio.h>  // _getch()
+#else
+#  include <termios.h>
+#  include <unistd.h>
+
+  int _getch(void) {
+    struct termios oldt, newt;
+    tcgetattr( STDIN_FILENO, &oldt );
+    newt = oldt;
+    newt.c_lflag &= ~( ICANON | ECHO );
+    tcsetattr( STDIN_FILENO, TCSANOW, &newt );
+    int ch = getchar();
+    tcsetattr( STDIN_FILENO, TCSANOW, &oldt );
+    return ch;
+  }
+#endif
+
+#include <curl/curl.h>
+
+#define VERSION_STR  "V1.0"
+
+// error handling macros
+#define my_curl_easy_setopt(A, B, C) \
+  if ((res = curl_easy_setopt((A), (B), (C))) != CURLE_OK) \
+    fprintf(stderr, "curl_easy_setopt(%s, %s, %s) failed: %d\n", #A, #B, #C, res);
+
+#define my_curl_easy_perform(A) \
+  if ((res = curl_easy_perform((A))) != CURLE_OK) \
+    fprintf(stderr, "curl_easy_perform(%s) failed: %d\n", #A, res);
+
+
+// send RTSP OPTIONS request
+void rtsp_options(CURL *curl, const char *uri) {
+    CURLcode res = CURLE_OK;
+    printf("\nRTSP: OPTIONS %s\n", uri);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_STREAM_URI, uri);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_REQUEST, CURL_RTSPREQ_OPTIONS);
+    my_curl_easy_perform(curl);
+}
+
+
+// send RTSP DESCRIBE request and write sdp response to a file
+void rtsp_describe(CURL *curl, const char *uri, const char *sdp_filename) {
+    CURLcode res = CURLE_OK;
+    printf("\nRTSP: DESCRIBE %s\n", uri);
+    FILE *sdp_fp = fopen(sdp_filename, "wt");
+    if (sdp_fp == NULL) {
+        fprintf(stderr, "Could not open '%s' for writing\n", sdp_filename);
+        sdp_fp = stdout;
+    } else {
+        printf("Writing SDP to '%s'\n", sdp_filename);
+    }
+    my_curl_easy_setopt(curl, CURLOPT_WRITEDATA, sdp_fp);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_REQUEST, CURL_RTSPREQ_DESCRIBE);
+    my_curl_easy_perform(curl);
+    my_curl_easy_setopt(curl, CURLOPT_WRITEDATA, stdout);
+    if (sdp_fp != stdout) {
+        fclose(sdp_fp);
+    }
+}
+
+
+// send RTSP SETUP request
+void rtsp_setup(CURL *curl, const char *uri, const char *transport) {
+    CURLcode res = CURLE_OK;
+    printf("\nRTSP: SETUP %s\n", uri);
+    printf("      TRANSPORT %s\n", transport);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_STREAM_URI, uri);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_TRANSPORT, transport);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_REQUEST, CURL_RTSPREQ_SETUP);
+    my_curl_easy_perform(curl);
+}
+
+
+// send RTSP PLAY request
+void rtsp_play(CURL *curl, const char *uri, const char *range) {
+    CURLcode res = CURLE_OK;
+    printf("\nRTSP: PLAY %s\n", uri);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_STREAM_URI, uri);
+    my_curl_easy_setopt(curl, CURLOPT_RANGE, range);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_REQUEST, CURL_RTSPREQ_PLAY);
+    my_curl_easy_perform(curl);
+}
+
+
+// send RTSP TEARDOWN request
+void rtsp_teardown(CURL *curl, const char *uri) {
+    CURLcode res = CURLE_OK;
+    printf("\nRTSP: TEARDOWN %s\n", uri);
+    my_curl_easy_setopt(curl, CURLOPT_RTSP_REQUEST, CURL_RTSPREQ_TEARDOWN);
+    my_curl_easy_perform(curl);
+}
+
+
+// convert url into an sdp filename
+void get_sdp_filename(const char *url, char *sdp_filename) {
+    strcpy(sdp_filename, "video.sdp");
+    const char *s = strrchr(url, '/');
+    if (s != NULL) {
+        s++;
+        if (s[0] != '\0') {
+            sprintf(sdp_filename, "%s.sdp", s);
+        }
+    }
+}
+
+
+// scan sdp file for media control attribute
+void get_media_control_attribute(const char *sdp_filename, char *control) {
+    control[0] = '\0';
+    int max_len = 256;
+    char *s = new char[max_len];
+    FILE *sdp_fp = fopen(sdp_filename, "rt");
+    if (sdp_fp != NULL) {
+        while (fgets(s, max_len - 2, sdp_fp) != NULL) {
+            sscanf(s, " a = control: %s", control);
+        }
+        fclose(sdp_fp);
+    }
+    delete []s;
+}
+
+
+// main app
+int main(int argc, char * const argv[]) {
+    const char *transport = "RTP/AVP;unicast;client_port=1234-1235";  // UDP		
+//    const char *transport = "RTP/AVP/TCP;unicast;client_port=1234-1235";  // TCP
+    const char *range = "0.000-";
+    int rc = EXIT_SUCCESS;
+
+    printf("\nRTSP request %s\n", VERSION_STR);
+    printf("    Project web site: http://code.google.com/p/rtsprequest/\n");
+    printf("    Requires cURL V7.20 or greater\n\n");
+
+    // check command line
+    char *basename = NULL;
+    if ((argc != 2) && (argc != 3)) {
+        basename = strrchr(argv[0], '/');
+        if (basename == NULL) {
+            basename = strrchr(argv[0], '\\');
+        }
+        if (basename == NULL) {
+            basename = argv[0];
+        } else {
+            basename++;
+        }
+        printf("Usage:   %s url [transport]\n", basename);
+        printf("         url of video server\n");
+        printf("         transport (optional) specifier for media stream protocol\n");
+        printf("         default transport: %s\n", transport);
+        printf("Example: %s rtsp://192.168.0.2/media/video1\n\n", basename);
+        rc = EXIT_FAILURE;
+    } else {
+        const char *url = argv[1];
+        char *uri = new char[strlen(url) + 32];
+        char *sdp_filename = new char[strlen(url) + 32];
+        char *control = new char[strlen(url) + 32];
+        get_sdp_filename(url, sdp_filename);
+        if (argc == 3) {
+            transport = argv[2];
+        }
+
+        // initialize curl
+        CURLcode res = CURLE_OK;
+        res = curl_global_init(CURL_GLOBAL_ALL);
+        if (res == CURLE_OK) {
+            curl_version_info_data *data = curl_version_info(CURLVERSION_NOW);
+            fprintf(stderr, "    cURL V%s loaded\n", data->version);
+
+            // initialize this curl session
+            CURL *curl = curl_easy_init();
+            if (curl != NULL) {
+                my_curl_easy_setopt(curl, CURLOPT_VERBOSE, 0L);
+                my_curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 1L);
+                my_curl_easy_setopt(curl, CURLOPT_WRITEHEADER, stdout);
+                my_curl_easy_setopt(curl, CURLOPT_URL, url);
+
+                // request server options
+                sprintf(uri, "%s", url);
+                rtsp_options(curl, uri);
+
+                // request session description and write response to sdp file
+                rtsp_describe(curl, uri, sdp_filename);
+
+                // get media control attribute from sdp file
+                get_media_control_attribute(sdp_filename, control);
+
+                // setup media stream
+                sprintf(uri, "%s/%s", url, control);
+                rtsp_setup(curl, uri, transport);
+
+                // start playing media stream
+                sprintf(uri, "%s/", url);
+                rtsp_play(curl, uri, range);
+                printf("Playing video, press any key to stop ...");
+                _getch();
+                printf("\n");
+
+                // teardown session
+                rtsp_teardown(curl, uri);
+
+                // cleanup
+                curl_easy_cleanup(curl);
+                curl = NULL;
+            } else {
+                fprintf(stderr, "curl_easy_init() failed\n");
+            }
+            curl_global_cleanup();
+        } else {
+            fprintf(stderr, "curl_global_init(%s) failed\n", "CURL_GLOBAL_ALL", res);
+        }
+        delete []control;
+        delete []sdp_filename;
+        delete []uri;
+    }
+
+    return rc;
+}