From: Michal Sojka <sojkam1@fel.cvut.cz>
Date: Wed, 5 May 2010 23:14:29 +0000 (+0200)
Subject: Started implementation of "correct" O_DIRECT handling
X-Git-Url: https://rtime.felk.cvut.cz/gitweb/frescor/ffmpeg.git/commitdiff_plain/5483685f884879c32edbf988ce11a7fb6f6bfb41

Started implementation of "correct" O_DIRECT handling

We still need to implement fseek().
---

diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
index f270139a9..491e7c76d 100644
--- a/libavformat/aviobuf.c
+++ b/libavformat/aviobuf.c
@@ -24,6 +24,8 @@
 #include "avformat.h"
 #include "avio.h"
 #include <stdarg.h>
+#include <unistd.h>
+#include <malloc.h>
 
 #define IO_BUFFER_SIZE 32768
 
@@ -77,22 +79,36 @@ ByteIOContext *av_alloc_put_byte(
     return s;
 }
 
+#define BLOCK_SIZE 512
+
 static void flush_buffer(ByteIOContext *s)
 {
+    size_t data_len = s->buf_ptr - s->buffer;
+    size_t to_write = (data_len + BLOCK_SIZE - 1) & ~(BLOCK_SIZE - 1);
+    int64_t res = AVERROR(EPIPE);
+    av_log(NULL, AV_LOG_ERROR, "YYY dl=%u, tw=%u\n", data_len, to_write);
     if (s->buf_ptr > s->buffer) {
         if (s->write_packet && !s->error){
-            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
+            int ret= s->write_packet(s->opaque, s->buffer, to_write);
             if(ret < 0){
                 s->error = ret;
             }
         }
         if(s->update_checksum){
+	    av_log(NULL, AV_LOG_ERROR, "Checksumming not implemented in O_DIRECT patch\n");
             s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
             s->checksum_ptr= s->buffer;
         }
-        s->pos += s->buf_ptr - s->buffer;
+        s->pos += to_write - BLOCK_SIZE;
+	memcpy(s->buffer, &s->buffer[to_write], data_len - to_write + BLOCK_SIZE);
+	s->buf_ptr -= to_write - BLOCK_SIZE;
+
+        if (s->seek)
+	    res = s->seek(s->opaque, s->pos, SEEK_SET);
+	if (res < 0)
+	    av_log(NULL, AV_LOG_ERROR, "seek error inside flush_buffer: %lld\n", res);
+	av_log(NULL, AV_LOG_ERROR, "ZZZ tw=%u, pos=%d\n", to_write, s->pos);
     }
-    s->buf_ptr = s->buffer;
 }
 
 void put_byte(ByteIOContext *s, int b)
@@ -146,6 +162,8 @@ int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
             return offset1;
         offset += offset1;
     }
+    av_log(NULL, AV_LOG_ERROR, "SEEK to %llu\n", offset);
+
     offset1 = offset - pos;
     if (!s->must_flush &&
         offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
@@ -167,6 +185,7 @@ int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
             s->must_flush = 1;
         }
 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
+#warning TODO read the whole block from the file to the buffer
         if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
             return res;
         if (!s->write_flag)
@@ -538,7 +557,8 @@ int url_fdopen(ByteIOContext **s, URLContext *h)
     } else {
         buffer_size = IO_BUFFER_SIZE;
     }
-    buffer = av_malloc(buffer_size);
+    buffer_size = 2*buffer_size+BLOCK_SIZE;
+    buffer = memalign(sysconf(_SC_PAGESIZE), buffer_size);
     if (!buffer)
         return AVERROR(ENOMEM);
 
diff --git a/libavformat/file.c b/libavformat/file.c
index da0ce1509..5cc887d1c 100644
--- a/libavformat/file.c
+++ b/libavformat/file.c
@@ -19,6 +19,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#define _GNU_SOURCE
 #include "libavutil/avstring.h"
 #include "avformat.h"
 #include <fcntl.h>
@@ -50,6 +51,7 @@ static int file_open(URLContext *h, const char *filename, int flags)
 #ifdef O_BINARY
     access |= O_BINARY;
 #endif
+    access |= O_DIRECT;
     fd = open(filename, access, 0666);
     if (fd < 0)
         return AVERROR(ENOENT);