Sync cache contents to disk before unlocking it (#84)

messages/libltfs/root.txt

@@ -791,6 +791,7 @@ root:table {
 		17252W:string { "Invalid value (%s) in the %s tag in UID %lld." }
 		17253E:string { "Cannot get tape parameters : %s (%d)." }
 		17254E:string { "This cartridge cannot be reformatted in the drive (0x%02x, %d)." }
+		17255I:string { "Cannot open %s cache for sync (%d)." }
 
 		// For Debug 19999I:string { "%s %s %d." }
 

src/libltfs/xml_writer.c

@@ -275,6 +275,7 @@ static int _copy_file_contents(int dest, int src)
 	}
 
 	free(buf);
+	fsync(dest);
 
 	if (len_read) {
 		ltfsmsg(LTFS_ERR, 17246E, "_copy_file unexpected read", errno);

src/libltfs/xml_writer_libltfs.c

@@ -62,6 +62,11 @@
 #include "pathname.h"
 #include "arch/time_internal.h"
 
+/* O_BINARY is defined only in MinGW */
+#ifndef O_BINARY
+#define O_BINARY 0
+#endif
+
 /* Structure to control EE's file offset cache and sync file list */
 struct ltfsee_cache
 {
@@ -708,7 +713,7 @@ xmlBufferPtr xml_make_schema(const char *creator, const struct ltfs_index *idx)
 
 static int _commit_offset_caches(const char* path, const struct ltfs_index *idx)
 {
-	int ret = 0;
+	int ret = 0, fd = -1;
 	char *offset_name = NULL, *sync_name = NULL;
 	char *offset_new = NULL, *sync_new = NULL;
 
@@ -720,6 +725,15 @@ static int _commit_offset_caches(const char* path, const struct ltfs_index *idx)
 			if (ret > 0) {
 				unlink(offset_name);
 				rename(offset_new, offset_name);
+				fd = open(offset_name, O_RDWR | O_BINARY,
+						  S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
+				if (fd >= 0) {
+					fsync(fd);
+					close(fd);
+					fd = -1;
+				} else {
+					ltfsmsg(LTFS_INFO, 17255I, offset_name, errno);
+				}
 				free(offset_name);
 			}
 			free(offset_new);
@@ -731,6 +745,15 @@ static int _commit_offset_caches(const char* path, const struct ltfs_index *idx)
 			if (ret > 0) {
 				unlink(sync_name);
 				rename(sync_new, sync_name);
+				fd = open(sync_name, O_RDWR | O_BINARY,
+						  S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
+				if (fd >= 0) {
+					fsync(fd);
+					close(fd);
+					fd = -1;
+				} else {
+					ltfsmsg(LTFS_INFO, 17255I, sync_name, errno);
+				}
 				free(sync_name);
 			}
 			free(sync_new);