1 files changed, 30 insertions, 14 deletions

diff --git a/libbb/loop.c b/libbb/loop.c
index 10217931b..00e3d6236 100644
--- a/libbb/loop.c
+++ b/libbb/loop.c
@@ -51,15 +51,30 @@ typedef struct {
 } bb_loop_info;
 #endif
 
-extern int del_loop(const char *device)
+char *query_loop(const char *device)
 {
-        int fd,rc=0;
+        int fd;
+        bb_loop_info loopinfo;
+        char *dev=0;
+        
+        if ((fd = open(device, O_RDONLY)) < 0) return 0;
+        if (!ioctl(fd, BB_LOOP_GET_STATUS, &loopinfo))
+                dev=bb_xasprintf("%ld %s", (long) loopinfo.lo_offset,
+                                loopinfo.lo_file_name);
+        close(fd);
 
-        if ((fd = open(device, O_RDONLY)) < 0) rc=1;
-        else {
-                if (ioctl(fd, LOOP_CLR_FD, 0) < 0) rc=1;
-                close(fd);
-        }
+        return dev;
+}       
+
+
+int del_loop(const char *device)
+{
+        int fd, rc;
+
+        if ((fd = open(device, O_RDONLY)) < 0) return 1;
+        rc=ioctl(fd, LOOP_CLR_FD, 0);
+        close(fd);
+        
         return rc;
 }
 
@@ -69,9 +84,9 @@ extern int del_loop(const char *device)
    search will re-use an existing loop device already bound to that
    file/offset if it finds one.
  */
-extern int set_loop(char **device, const char *file, int offset)
+int set_loop(char **device, const char *file, int offset)
 {
-        char dev[20];
+        char dev[20], *try;
         bb_loop_info loopinfo;
         struct stat statbuf;
         int i, dfd, ffd, mode, rc=1;
@@ -81,20 +96,21 @@ extern int set_loop(char **device, const char *file, int offset)
                 return errno;
 
         /* Find a loop device.  */
+        try=*device ? : dev;
         for(i=0;rc;i++) {
                 sprintf(dev, LOOP_FORMAT, i++);
                 /* Ran out of block devices, return failure.  */
-                if(stat(*device ? *device : dev, &statbuf) ||
-                                !S_ISBLK(statbuf.st_mode)) {
+                if(stat(try, &statbuf) || !S_ISBLK(statbuf.st_mode)) {
                         rc=ENOENT;
                         break;
                 }
                 /* Open the sucker and check its loopiness.  */
-                if((dfd=open(dev, mode))<0 && errno==EROFS)
-                        dfd=open(dev,mode=O_RDONLY);
+                if((dfd=open(try, mode))<0 && errno==EROFS)
+                        dfd=open(try,mode=O_RDONLY);
                 if(dfd<0) continue;
 
                 rc=ioctl(dfd, BB_LOOP_GET_STATUS, &loopinfo);
+
                 /* If device free, claim it.  */
                 if(rc && errno==ENXIO) {
                         memset(&loopinfo, 0, sizeof(loopinfo));
@@ -110,7 +126,7 @@ extern int set_loop(char **device, const char *file, int offset)
                    without using losetup manually is problematic.)
                  */
                 } else if(strcmp(file,loopinfo.lo_file_name)
-                                        || offset!=loopinfo.lo_offset) rc=1;
+                                        || offset!=loopinfo.lo_offset) rc=-1;
                 close(dfd);
                 if(*device) break;
         }