input_stream: use "goffset" instead of "off_t"

The "off_t" type may change when you enable or disable large file
support on 32 bit platforms.  This caused severe ABI problems within
MPD when we enabled LFS for the first time: two sources included
config.h and sys/types.h in different order, and had different off_t
sizes - leading to memory corruption because of ABI incompatibility.
This patch attempts to get rid of all public "off_t" uses: it removes
"off_t" from the input_stream ABI/API, and switches to GLib's 64 bit
"goffset" type.  This may hurt 32 bit embedded platforms a tiny bit,
but that's not even measurable.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/input/file_input_plugin.c b/src/input/file_input_plugin.c
index 64a4030ab..5dbbefcce 100644
--- a/src/input/file_input_plugin.c
+++ b/src/input/file_input_plugin.c
@@ -17,6 +17,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include "config.h" /* must be first for large file support */
 #include "input/file_input_plugin.h"
 #include "input_plugin.h"
 
@@ -92,11 +93,11 @@ input_file_open(struct input_stream *is, const char *filename)
 }
 
 static bool
-input_file_seek(struct input_stream *is, off_t offset, int whence)
+input_file_seek(struct input_stream *is, goffset offset, int whence)
 {
 	int fd = GPOINTER_TO_INT(is->data);
 
-	offset = lseek(fd, offset, whence);
+	offset = (goffset)lseek(fd, (off_t)offset, whence);
 	if (offset < 0) {
 		is->error = errno;
 		return false;