try to handle sendfile corner cases better

2 files changed, 22 insertions, 7 deletions

diff --git a/src/daemon/daemon.c b/src/daemon/daemon.c
index d220973e..a9778c61 100644
--- a/src/daemon/daemon.c
+++ b/src/daemon/daemon.c
@@ -709,7 +709,8 @@ send_param_adapter (struct MHD_Connection *connection,
 #if LINUX
   int fd;
   off_t offset;
-  int ret;
+  off_t left;
+  ssize_t ret;
 #endif
   if (connection->socket_fd == -1)
     return -1;
@@ -723,14 +724,28 @@ send_param_adapter (struct MHD_Connection *connection,
     {
       /* can use sendfile */
       offset = (off_t) connection->response_write_position + connection->response->fd_off;
+      left = connection->response->total_size - offset;
+      if (left > SSIZE_MAX)
+        left = SSIZE_MAX; /* cap at return value limit */
       ret = sendfile (connection->socket_fd, 
                       fd,
                       &offset,
-                      connection->response->total_size - offset);
-      if ( (ret == -1) &&
-           (errno == EINTR) )
-        return 0;
-      return ret;
+                      left);
+      if (ret != -1)
+        return ret;
+      if (ret == -1) 
+        {
+          if (EINTR == errno) 
+            return 0;
+          if ( (EINVAL == errno) ||
+               (EBADF == errno) ||
+               (EAGAIN == errno) )
+            return -1; 
+          /* None of the 'usual' sendfile errors occurred, so we should try
+             to fall back to 'SEND'; see also this thread for info on
+             odd libc/Linux behavior with sendfile:
+             http://lists.gnu.org/archive/html/libmicrohttpd/2011-02/msg00015.html */
+        }
     }
 #endif
   return SEND (connection->socket_fd, other, i, MSG_NOSIGNAL | MSG_DONTWAIT);
diff --git a/src/include/microhttpd.h b/src/include/microhttpd.h
index 67240fc8..e1bc1239 100644
--- a/src/include/microhttpd.h
+++ b/src/include/microhttpd.h
@@ -106,7 +106,7 @@ extern "C"
 /**
  * Current version of the library.
  */
-#define MHD_VERSION 0x00090700
+#define MHD_VERSION 0x00090701
 
 /**
  * MHD-internal return code for "YES".