Try to improve and export the SDP formatting helpers

[vlc] / src / stream_output / sdp.c

diff --git a/src/stream_output/sdp.c b/src/stream_output/sdp.c
index d88a81a43480f6f7851cfe5ed3169948270066e6..b5cde41eefb2c4409314419fda4c02613d70f0b0 100644 (file)
--- a/src/stream_output/sdp.c
+++ b/src/stream_output/sdp.c
@@ -86,7 +86,7 @@ static vlc_bool_t IsSDPString (const char *str)
 }
 
 
-char *StartSDP (const char *name, const char *description, const char *url,
+char *sdp_Start (const char *name, const char *description, const char *url,
                 const char *email, const char *phone,
                 const struct sockaddr *src, socklen_t srclen,
                 const struct sockaddr *addr, socklen_t addrlen)
@@ -157,59 +157,85 @@ char *StartSDP (const char *name, const char *description, const char *url,
 }
 
 
-char *vAddSDPMedia (const char *type, int dport, const char *protocol,
-                    unsigned pt, const char *rtpmap,
-                    const char *fmtpfmt, va_list ap)
+static char *
+vsdp_AddAttribute (char **sdp, const char *name, const char *fmt, va_list ap)
 {
-    char *sdp_media = NULL;
+    size_t oldlen = strlen (*sdp);
+    size_t addlen =
+        sizeof ("a=:\r\n") + strlen (name) + vsnprintf (NULL, 0, fmt, ap);
+    char *ret = realloc (*sdp, oldlen + addlen);
+
+    if (ret == NULL)
+        return NULL;
+
+    oldlen += sprintf (ret + oldlen, "a=%s:", name);
+    sprintf (ret + oldlen, fmt, ap);
+    return *sdp = ret;
+}
+
+
+char *sdp_AddAttribute (char **sdp, const char *name, const char *fmt, ...)
+{
+    char *ret;
+
+    if (fmt != NULL)
+    {
+        va_list ap;
+
+        va_start (ap, fmt);
+        ret = vsdp_AddAttribute (sdp, name, fmt, ap);
+        va_end (ap);
+    }
+    else
+    {
+        size_t oldlen = strlen (*sdp);
+        ret = realloc (*sdp, oldlen + strlen (name) + sizeof ("a=\r\n"));
+        if (ret == NULL)
+            return NULL;
+
+        sprintf (ret + oldlen, "a=%s\r\n", name);
+    }
+    return ret;
+}
+
+
+char *sdp_AddMedia (char **sdp,
+                    const char *type, const char *protocol, int dport,
+                    unsigned pt, vlc_bool_t bw_indep, unsigned bw,
+                    const char *rtpmap, const char *fmtp)
+{
+    char *newsdp, *ptr;
+    size_t inlen = strlen (*sdp), outlen = inlen;
 
     /* Some default values */
     if (type == NULL)
         type = "video";
-    if (dport == 0)
-        dport = 9;
     if (protocol == NULL)
         protocol = "RTP/AVP";
     assert (pt < 128u);
 
-    /* RTP payload type map */
-    char sdp_rtpmap[rtpmap ? (sizeof ("a=rtpmap:123 *\r\n") + strlen (rtpmap)) : 1];
-    if (rtpmap != NULL)
-        sprintf (sdp_rtpmap, "a=rtpmap:%u %s\r\n", pt, rtpmap);
-    else
-        *sdp_rtpmap = '\0';
+    outlen += snprintf (NULL, 0,
+                        "m=%s %u %s %d\r\n"
+                        "b=RR:0\r\n",
+                        type, dport, protocol, pt);
 
-    /* Format parameters */
-    char *fmtp = NULL;
-    if ((fmtpfmt != NULL)
-     && (vasprintf (&fmtp, fmtpfmt, ap) == -1))
+    newsdp = realloc (*sdp, outlen + 1);
+    if (newsdp == NULL)
         return NULL;
 
-    char sdp_fmtp[fmtp ? (sizeof ("a=fmtp:123 *\r\n") + strlen (fmtp)) : 1];
-    if (fmtp != NULL)
-    {
-        sprintf (sdp_fmtp, "a=fmtp:%u %s\r\n", pt, fmtp);
-        free (fmtp);
-    }
-    else
-        *sdp_fmtp = '\0';
-
-    if (asprintf (&sdp_media, "m=%s %u %s %d\r\n" "b=RR:0\r\n" "%s" "%s",
-                  type, dport, protocol, pt,
-                  sdp_rtpmap, sdp_fmtp) == -1)
-        return NULL;
+    *sdp = newsdp;
+    ptr = newsdp + inlen;
 
-    return sdp_media;
-}
+    ptr += sprintf (ptr, "m=%s %u %s %d\r\n"
+                         "b=RR:0\r\n",
+                         type, dport, protocol, pt);
 
+    /* RTP payload type map */
+    if (rtpmap != NULL)
+        sdp_AddAttribute ("rtpmap", "%u %s", pt, rtpmap);
+    /* Format parameters */
+    if (fmtp != NULL)
+        sdp_AddAttribute ("fmtp", "%u %s", pt, fmtp);
 
-char *AddSDPMedia (const char *type, int dport, const char *protocol,
-                    unsigned pt, const char *rtpmap, const char *fmtpfmt, ...)
-{
-    va_list ap;
-    char *ret;
-    va_start (ap, fmtpfmt);
-    ret = vAddSDPMedia (type, dport, protocol, pt, rtpmap, fmtpfmt, ap);
-    va_end (ap);
-    return ret;
+    return newsdp;
 }