bzip plugin: Seeking streams backwards was broken.

--HG--
branch : HEAD

diff --git a/src/plugins/zlib/istream-zlib.c b/src/plugins/zlib/istream-zlib.c
index 5d7a6a4c16b9141a1824a87e2c2588f869dbaf93..4b5b6e8221784b7a24123aadaee2779a8c3e33aa 100644 (file)
--- a/src/plugins/zlib/istream-zlib.c
+++ b/src/plugins/zlib/istream-zlib.c
@@ -19,6 +19,8 @@
    this pretty large */
 #define DEFAULT_MAX_BUFFER_SIZE (1024*1024)
 
+#include <unistd.h>
+
 struct zlib_istream {
        struct istream_private istream;
 
@@ -124,7 +126,17 @@ i_stream_zlib_seek(struct istream_private *stream, uoff_t v_offset, bool mark)
 
 #ifndef HAVE_GZSEEK
        if (v_offset < start_offset) {
+               /* need to reopen, but since closing the file closes the
+                  file descriptor we'll have to duplicate it first. */
+               int fd = dup(zstream->fd);
+               if (fd == -1) {
+                       stream->istream.stream_errno = errno;
+                       i_error("zlib istream: dup() failed: %m");
+                       i_stream_close(&stream->istream);
+                       return;
+               }
                gzclose(zstream->file);
+               zstream->fd = fd;
                zstream->file = gzdopen(zstream->fd, "r");
        }
 #else