[FFmpeg-devel] [PATCH] libavformat/cache: don't treat 0 as EOF libavformat/aviobuf: don't treat 0 as EOF libavformat/avio: retry_transfer_wrapper: don't treat 0 as EOF

[Daniel Kucera]

transfer_func variable passed to retry_transfer_wrapper
are h->prot->url_read and h->prot->url_write functions.
These need to return EOF or other error properly.
In case of returning >= 0, url_read/url_write is retried
until error is returned.

Signed-off-by: Daniel Kucera <daniel.kucera at gmail.com>
---
 libavformat/avio.c    |  6 ++++--
 libavformat/aviobuf.c | 20 ++++++++++++--------
 libavformat/cache.c   |  4 ++--
 3 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/libavformat/avio.c b/libavformat/avio.c
index 64248e098b..d3004c007f 100644
--- a/libavformat/avio.c
+++ b/libavformat/avio.c
@@ -391,8 +391,10 @@ static inline int retry_transfer_wrapper(URLContext *h, uint8_t *buf,
                 }
                 av_usleep(1000);
             }
-        } else if (ret < 1)
-            return (ret < 0 && ret != AVERROR_EOF) ? ret : len;
+        } else if (ret == AVERROR_EOF)
+	    return (len > 0) ? len : AVERROR_EOF;
+        else if (ret < 0)
+            return ret;
         if (ret) {
             fast_retries = FFMAX(fast_retries, 2);
             wait_since = 0;
diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
index 636cb46161..0d4eb051e1 100644
--- a/libavformat/aviobuf.c
+++ b/libavformat/aviobuf.c
@@ -572,13 +572,14 @@ static void fill_buffer(AVIOContext *s)
     if (s->read_packet)
         len = s->read_packet(s->opaque, dst, len);
     else
-        len = 0;
-    if (len <= 0) {
+        len = AVERROR_EOF;
+    if (len == AVERROR_EOF) {
         /* do not modify buffer if EOF reached so that a seek back can
            be done without rereading data */
         s->eof_reached = 1;
-        if (len < 0)
-            s->error = len;
+    } else if (len < 0) {
+        s->eof_reached = 1;
+        s->error= len;
     } else {
         s->pos += len;
         s->buf_ptr = dst;
@@ -646,13 +647,16 @@ int avio_read(AVIOContext *s, unsigned char *buf, int size)
                 // bypass the buffer and read data directly into buf
                 if(s->read_packet)
                     len = s->read_packet(s->opaque, buf, size);
-
-                if (len <= 0) {
+                else
+                    len = AVERROR_EOF;
+                if (len == AVERROR_EOF) {
                     /* do not modify buffer if EOF reached so that a seek back can
                     be done without rereading data */
                     s->eof_reached = 1;
-                    if(len<0)
-                        s->error= len;
+                    break;
+                } else if (len < 0) {
+                    s->eof_reached = 1;
+                    s->error= len;
                     break;
                 } else {
                     s->pos += len;
diff --git a/libavformat/cache.c b/libavformat/cache.c
index 6aabca2e78..66bbbf54c9 100644
--- a/libavformat/cache.c
+++ b/libavformat/cache.c
@@ -201,7 +201,7 @@ static int cache_read(URLContext *h, unsigned char *buf, int size)
     }
 
     r = ffurl_read(c->inner, buf, size);
-    if (r == 0 && size>0) {
+    if (r == AVERROR_EOF && size>0) {
         c->is_true_eof = 1;
         av_assert0(c->end >= c->logical_pos);
     }
@@ -263,7 +263,7 @@ resolve_eof:
                 if (whence == SEEK_SET)
                     size = FFMIN(sizeof(tmp), pos - c->logical_pos);
                 ret = cache_read(h, tmp, size);
-                if (ret == 0 && whence == SEEK_END) {
+                if (ret == AVERROR_EOF && whence == SEEK_END) {
                     av_assert0(c->is_true_eof);
                     goto resolve_eof;
                 }
-- 
2.11.0