[vlc-devel] [RFC PATCH 1/2] libvlc: media: remove usage of ssize_t

[Thomas Guillem]

It's in POSIX but not in C standard.
---
 include/vlc/libvlc_media.h   | 10 +++++-----
 modules/access/imem-access.c | 13 ++++++-------
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/include/vlc/libvlc_media.h b/include/vlc/libvlc_media.h
index 15933c5..d7b7aab 100644
--- a/include/vlc/libvlc_media.h
+++ b/include/vlc/libvlc_media.h
@@ -318,18 +318,18 @@ typedef int (*libvlc_media_open_cb)(void *opaque, void **datap,
  * \param opaque private pointer as set by the @ref libvlc_media_open_cb
  *               callback
  * \param buf start address of the buffer to read data into
- * \param len bytes length of the buffer
+ * \param len bytes length of the buffer. The callback should set the number of
+ * bytes that is actually read (0 on end-of-stream) [IN/OUT]
  *
- * \return strictly positive number of bytes read, 0 on end-of-stream,
- *         or -1 on non-recoverable error
+ * \return 0 on success, -1 on error.
  *
  * \note If no data is immediately available, then the callback should sleep.
  * \warning The application is responsible for avoiding deadlock situations.
  * In particular, the callback should return an error if playback is stopped;
  * if it does not return, then libvlc_media_player_stop() will never return.
  */
-typedef ssize_t (*libvlc_media_read_cb)(void *opaque, unsigned char *buf,
-                                        size_t len);
+typedef int (*libvlc_media_read_cb)(void *opaque, unsigned char *buf,
+                                    size_t *len);
 
 /**
  * Callback prototype to seek a custom bitstream input media.
diff --git a/modules/access/imem-access.c b/modules/access/imem-access.c
index d7a80bb..5921a7e 100644
--- a/modules/access/imem-access.c
+++ b/modules/access/imem-access.c
@@ -31,7 +31,7 @@
 struct access_sys_t
 {
     void *opaque;
-    ssize_t (*read_cb)(void *, unsigned char *, size_t);
+    int (*read_cb)(void *, unsigned char *, size_t *);
     int (*seek_cb)(void *, uint64_t);
     void (*close_cb)(void *);
     uint64_t size;
@@ -41,14 +41,13 @@ static ssize_t Read(access_t *access, void *buf, size_t len)
 {
     access_sys_t *sys = access->p_sys;
 
-    ssize_t val = sys->read_cb(sys->opaque, buf, len);
-
-    if (val < 0) {
+    if (sys->read_cb(sys->opaque, buf, &len) < 0)
+    {
         msg_Err(access, "read error");
-        val = 0;
+        return 0;
     }
-
-    return val;
+    else
+        return len;
 }
 
 static int Seek(access_t *access, uint64_t offset)
-- 
2.8.1