for #405, improve the HTT FLV to 3k. 2.0.169

@@ -716,7 +716,8 @@ The play HTTP FLV benchmark by [SB](https://github.com/simple-rtmp-server/srs-be
 |   Update      |    SRS    |    Clients    |     Type      |    CPU    |  Memory   | Commit        |
 | ------------- | --------- | ------------- | ------------- | --------- | --------  | ------------  |
 |   2014-05-24  |   2.0.167 |   1.0k(1000)  |   players     |   82%     |   86MB    |   -           |
-|   2014-05-24  |   2.0.168 |   2.3k(2300)  |   players     |   92%     |   276MB   |   -           |
+|   2014-05-24  |   2.0.168 |   2.3k(2300)  |   players     |   92%     |   276MB   |   [code][p17] |
+|   2014-05-24  |   2.0.169 |   3.0k(3000)  |   players     |   94%     |   188MB   |   [code][p18] |
 
 ### Latency benchmark
 
@@ -832,6 +833,7 @@ Winlin
 [p14]: https://github.com/simple-rtmp-server/srs/commit/10297fab519811845b549a8af40a6bcbd23411e8
 [p15]: https://github.com/simple-rtmp-server/srs/commit/0d6b91039d408328caab31a1077d56a809b6bebc
 [p16]: https://github.com/simple-rtmp-server/srs/commit/0d6b91039d408328caab31a1077d56a809b6bebc
+[p17]: https://github.com/simple-rtmp-server/srs/commit/fc995473eb02c7cf64b5b212b456e11f34aa7984
 
 [authors]: https://github.com/simple-rtmp-server/srs/blob/develop/AUTHORS.txt
 [bigthanks]: https://github.com/simple-rtmp-server/srs/wiki/v1_CN_Product#bigthanks

@@ -98,8 +98,14 @@ int SrsHttpResponseWriter::write(char* data, int size)
     
     if (!header_wrote) {
         write_header(SRS_CONSTS_HTTP_OK);
+        
+        if ((ret = send_header(data, size)) != ERROR_SUCCESS) {
+            srs_error("http: send header failed. ret=%d", ret);
+            return ret;
+        }
     }
     
+    // check the bytes send and content length.
     written += size;
     if (content_length != -1 && written > content_length) {
         ret = ERROR_HTTP_CONTENT_LENGTH;
@@ -107,11 +113,6 @@ int SrsHttpResponseWriter::write(char* data, int size)
         return ret;
     }
     
-    if ((ret = send_header(data, size)) != ERROR_SUCCESS) {
-        srs_error("http: send header failed. ret=%d", ret);
-        return ret;
-    }
-    
     // ignore NULL content.
     if (!data) {
         return ret;
@@ -143,6 +144,71 @@ int SrsHttpResponseWriter::write(char* data, int size)
     return ret;
 }
 
+int SrsHttpResponseWriter::writev(iovec* iov, int iovcnt, ssize_t* pnwrite)
+{
+    int ret = ERROR_SUCCESS;
+    
+    // when header not ready, or not chunked, send one by one.
+    if (!header_wrote || content_length != -1) {
+        ssize_t nwrite = 0;
+        for (int i = 0; i < iovcnt; i++) {
+            iovec* piovc = iov + i;
+            nwrite += piovc->iov_len;
+            if ((ret = write((char*)piovc->iov_base, (int)piovc->iov_len)) != ERROR_SUCCESS) {
+                return ret;
+            }
+        }
+        
+        if (pnwrite) {
+            *pnwrite = nwrite;
+        }
+        
+        return ret;
+    }
+    
+    // ignore NULL content.
+    if (iovcnt <= 0) {
+        return ret;
+    }
+    
+    // send in chunked encoding.
+    int nb_iovss = iovcnt * 4;
+    iovec* iovss = new iovec[nb_iovss];
+    SrsAutoFree(iovec, iovss);
+    
+    char* pheader_cache = header_cache;
+    for (int i = 0; i < iovcnt; i++) {
+        int left = SRS_HTTP_HEADER_CACHE_SIZE - (int)(pheader_cache - header_cache);
+        srs_assert(left > 0);
+        
+        iovec* data_iov = iov + i;
+        int nb_size = snprintf(pheader_cache, left, "%x", (int)data_iov->iov_len);
+        
+        iovec* iovs = iovss + (i * 4);
+        iovs[0].iov_base = (char*)pheader_cache;
+        iovs[0].iov_len = (int)nb_size;
+        iovs[1].iov_base = (char*)SRS_HTTP_CRLF;
+        iovs[1].iov_len = 2;
+        iovs[2].iov_base = (char*)data_iov->iov_base;
+        iovs[2].iov_len = (int)data_iov->iov_len;
+        iovs[3].iov_base = (char*)SRS_HTTP_CRLF;
+        iovs[3].iov_len = 2;
+        
+        pheader_cache += nb_size;
+    }
+    
+    ssize_t nwrite;
+    if ((ret = skt->writev(iovss, nb_iovss, &nwrite)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    if (pnwrite) {
+        *pnwrite = nwrite;
+    }
+    
+    return ret;
+}
+
 void SrsHttpResponseWriter::write_header(int code)
 {
     if (header_wrote) {
@@ -1513,6 +1579,11 @@ int SrsStreamWriter::write(void* buf, size_t count, ssize_t* pnwrite)
     return writer->write((char*)buf, (int)count);
 }
 
+int SrsStreamWriter::writev(iovec* iov, int iovcnt, ssize_t* pnwrite)
+{
+    return writer->writev(iov, iovcnt, pnwrite);
+}
+
 SrsLiveStream::SrsLiveStream(SrsSource* s, SrsRequest* r, SrsStreamCache* c)
 {
     source = s;

@@ -71,7 +71,11 @@ class SrsHttpMessage;
 
 #ifdef SRS_AUTO_HTTP_PARSER
 
-#define SRS_HTTP_HEADER_CACHE_SIZE 16
+// for HTTP FLV, each video/audio packet is send by 3 iovs,
+// while each iov is send by 4 sub iovs, that is needs 3 chunk header,
+// suppose each header is 16 length, 3*16=48 is ok.
+// that is, 512 can used for 16 iovs to send.
+#define SRS_HTTP_HEADER_CACHE_SIZE 512
 
 /**
  * response writer use st socket
@@ -105,6 +109,7 @@ public:
     virtual int final_request();
     virtual SrsHttpHeader* header();
     virtual int write(char* data, int size);
+    virtual int writev(iovec* iov, int iovcnt, ssize_t* pnwrite);
     virtual void write_header(int code);
     virtual int send_header(char* data, int size);
 };
@@ -541,6 +546,7 @@ public:
     virtual int64_t tellg();
 public:
     virtual int write(void* buf, size_t count, ssize_t* pnwrite);
+    virtual int writev(iovec* iov, int iovcnt, ssize_t* pnwrite);
 };
 
 /**

@@ -31,7 +31,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 // current release version
 #define VERSION_MAJOR       2
 #define VERSION_MINOR       0
-#define VERSION_REVISION    168
+#define VERSION_REVISION    169
 
 // server info.
 #define RTMP_SIG_SRS_KEY "SRS"

@@ -30,6 +30,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <fcntl.h>
 #include <sstream>
+#include <sys/uio.h>
 using namespace std;
 
 #include <srs_kernel_log.hpp>
@@ -145,6 +146,27 @@ int SrsFileWriter::write(void* buf, size_t count, ssize_t* pnwrite)
     return ret;
 }
 
+int SrsFileWriter::writev(iovec* iov, int iovcnt, ssize_t* pnwrite)
+{
+    int ret = ERROR_SUCCESS;
+    
+    ssize_t nwrite = 0;
+    for (int i = 0; i < iovcnt; i++) {
+        iovec* piov = iov + i;
+        ssize_t this_nwrite = 0;
+        if ((ret = write(piov->iov_base, piov->iov_len, &this_nwrite)) != ERROR_SUCCESS) {
+            return ret;
+        }
+        nwrite += this_nwrite;
+    }
+    
+    if (pnwrite) {
+        *pnwrite = nwrite;
+    }
+    
+    return ret;
+}
+
 SrsFileReader::SrsFileReader()
 {
     fd = -1;

@@ -31,6 +31,11 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <string>
 
+// for srs-librtmp, @see https://github.com/simple-rtmp-server/srs/issues/213
+#ifndef _WIN32
+#include <sys/uio.h>
+#endif
+
 /**
 * file writer, to write to file.
 */
@@ -62,6 +67,11 @@ public:
     * @param pnwrite the output nb_write, NULL to ignore.
     */
     virtual int write(void* buf, size_t count, ssize_t* pnwrite);
+    /**
+     * for the HTTP FLV, to writev to improve performance.
+     * @see https://github.com/simple-rtmp-server/srs/issues/405
+     */
+    virtual int writev(iovec* iov, int iovcnt, ssize_t* pnwrite);
 };
 
 /**

@@ -223,31 +223,24 @@ int SrsFlvEncoder::write_tag(char* header, int header_size, char* tag, int tag_s
 {
     int ret = ERROR_SUCCESS;
     
-    // write tag header.
-    if ((ret = _fs->write(header, header_size, NULL)) != ERROR_SUCCESS) {
-        if (!srs_is_client_gracefully_close(ret)) {
-            srs_error("write flv tag header failed. ret=%d", ret);
-        }
-        return ret;
-    }
-    
-    // write tag data.
-    if ((ret = _fs->write(tag, tag_size, NULL)) != ERROR_SUCCESS) {
-        if (!srs_is_client_gracefully_close(ret)) {
-            srs_error("write flv tag failed. ret=%d", ret);
-        }
-        return ret;
-    }
-    
     // PreviousTagSizeN UI32 Size of last tag, including its header, in bytes.
     char pre_size[SRS_FLV_PREVIOUS_TAG_SIZE];
     if ((ret = tag_stream->initialize(pre_size, SRS_FLV_PREVIOUS_TAG_SIZE)) != ERROR_SUCCESS) {
         return ret;
     }
     tag_stream->write_4bytes(tag_size + header_size);
-    if ((ret = _fs->write(pre_size, sizeof(pre_size), NULL)) != ERROR_SUCCESS) {
+    
+    iovec iovs[3];
+    iovs[0].iov_base = header;
+    iovs[0].iov_len = header_size;
+    iovs[1].iov_base = tag;
+    iovs[1].iov_len = tag_size;
+    iovs[2].iov_base = pre_size;
+    iovs[2].iov_len = sizeof(SRS_FLV_PREVIOUS_TAG_SIZE);
+    
+    if ((ret = _fs->writev(iovs, 3, NULL)) != ERROR_SUCCESS) {
         if (!srs_is_client_gracefully_close(ret)) {
-            srs_error("write flv previous tag size failed. ret=%d", ret);
+            srs_error("write flv tag failed. ret=%d", ret);
         }
         return ret;
     }

@@ -33,6 +33,11 @@
 #include <string>
 #include <vector>
 
+// for srs-librtmp, @see https://github.com/simple-rtmp-server/srs/issues/213
+#ifndef _WIN32
+#include <sys/uio.h>
+#endif
+
 class SrsFileReader;
 class SrsHttpHeader;
 class ISrsHttpMessage;
@@ -188,6 +193,11 @@ public:
     // the initial 512 bytes of written data to DetectContentType.
     // @param data, the data to send. NULL to flush header only.
     virtual int write(char* data, int size) = 0;
+    /**
+     * for the HTTP FLV, to writev to improve performance.
+     * @see https://github.com/simple-rtmp-server/srs/issues/405
+     */
+    virtual int writev(iovec* iov, int iovcnt, ssize_t* pnwrite) = 0;
     
     // WriteHeader sends an HTTP response header with status code.
     // If WriteHeader is not called explicitly, the first call to Write