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 */