1 files changed, 69 insertions, 1 deletions
diff --git a/utility.c b/utility.c
index 643c3b5f2..5ff03d7a0 100644
--- a/utility.c
+++ b/utility.c
@@ -1169,6 +1169,74 @@ extern int del_loop(const char *device)
     close(fd);
     return( TRUE);
 }
-#endif
+
+extern int set_loop(const char *device, const char *file, int offset, int *loopro)
+{
+	struct loop_info loopinfo;
+	int	fd, ffd, mode;
+	
+	mode = *loopro ? O_RDONLY : O_RDWR;
+	if ((ffd = open (file, mode)) < 0 && !*loopro
+	    && (errno != EROFS || (ffd = open (file, mode = O_RDONLY)) < 0)) {
+	  perror (file);
+	  return 1;
+	}
+	if ((fd = open (device, mode)) < 0) {
+	  close(ffd);
+	  perror (device);
+	  return 1;
+	}
+	*loopro = (mode == O_RDONLY);
+
+	memset(&loopinfo, 0, sizeof(loopinfo));
+	strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
+	loopinfo.lo_name[LO_NAME_SIZE-1] = 0;
+
+	loopinfo.lo_offset = offset;
+
+	loopinfo.lo_encrypt_key_size = 0;
+	if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
+		perror("ioctl: LOOP_SET_FD");
+		close(fd);
+		close(ffd);
+		return 1;
+	}
+	if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
+		(void) ioctl(fd, LOOP_CLR_FD, 0);
+		perror("ioctl: LOOP_SET_STATUS");
+		close(fd);
+		close(ffd);
+		return 1;
+	}
+	close(fd);
+	close(ffd);
+	return 0;
+}
+
+extern char *find_unused_loop_device (void)
+{
+	char dev[20];
+	int i, fd;
+	struct stat statbuf;
+	struct loop_info loopinfo;
+
+	for(i = 0; i <= 7; i++) {
+	    sprintf(dev, "/dev/loop%d", i);
+	    if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
+		if ((fd = open (dev, O_RDONLY)) >= 0) {
+		    if(ioctl (fd, LOOP_GET_STATUS, &loopinfo) == -1) {
+			if (errno == ENXIO) { /* probably free */
+			    close (fd);
+			    return strdup(dev);
+			}
+		    }
+		    close (fd);
+		}
+	    }
+	}
+        return NULL;
+}
+#endif /* BB_FEATURE_MOUNT_LOOP */
+
 
 /* END CODE */