diff options
-rw-r--r-- | libbb/loop.c | 53 |
1 files changed, 22 insertions, 31 deletions
diff --git a/libbb/loop.c b/libbb/loop.c index f7029d5..06b5185 100644 --- a/libbb/loop.c +++ b/libbb/loop.c @@ -2,21 +2,9 @@ /* * Utility routines. * - * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> + * Copyright (C) 1999-2005 by Erik Andersen <andersen@codepoet.org> * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. */ @@ -75,11 +63,12 @@ extern int del_loop(const char *device) return rc; } -// Returns 0 if mounted RW, 1 if mounted read-only, <0 for error. -// *device is loop device to use, or if *device==NULL finds a loop device to -// mount it on and sets *device to a strdup of that loop device name. This -// search will re-use an existing loop device already bound to that -// file/offset if it finds one. +/* Returns 0 if mounted RW, 1 if mounted read-only, <0 for error. + *device is loop device to use, or if *device==NULL finds a loop device to + mount it on and sets *device to a strdup of that loop device name. This + 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) { char dev[20]; @@ -87,37 +76,39 @@ extern int set_loop(char **device, const char *file, int offset) struct stat statbuf; int i, dfd, ffd, mode, rc=1; - // Open the file. Barf if this doesn't work. + /* Open the file. Barf if this doesn't work. */ if((ffd = open(file, mode=O_RDWR))<0 && (ffd = open(file,mode=O_RDONLY))<0) return errno; - - // Find a loop device + + /* Find a loop device. */ for(i=0;rc;i++) { sprintf(dev, LOOP_FORMAT, i++); - // Ran out of block devices, return failure. - if(stat(*device ? : dev, &statbuf) || !S_ISBLK(statbuf.st_mode)) { + /* Ran out of block devices, return failure. */ + if(stat(*device ? *device : dev, &statbuf) || + !S_ISBLK(statbuf.st_mode)) { rc=ENOENT; break; } - // Open the sucker and check its loopiness. + /* Open the sucker and check its loopiness. */ if((dfd=open(dev, mode))<0 && errno==EROFS) dfd=open(dev,mode=O_RDONLY); if(dfd<0) continue; rc=ioctl(dfd, BB_LOOP_GET_STATUS, &loopinfo); - // If device free, claim it. + /* If device free, claim it. */ if(rc && errno==ENXIO) { memset(&loopinfo, 0, sizeof(loopinfo)); safe_strncpy(loopinfo.lo_file_name, file, LO_NAME_SIZE); loopinfo.lo_offset = offset; - // Associate free loop device with file + /* Associate free loop device with file. */ if(!ioctl(dfd, LOOP_SET_FD, ffd) && !ioctl(dfd, BB_LOOP_SET_STATUS, &loopinfo)) rc=0; else ioctl(dfd, LOOP_CLR_FD, 0); - // If this block device already set up right, re-use it. - // (Yes this is racy, but associating two loop devices with the same - // file isn't pretty either. In general, mounting the same file twice - // without using losetup manually is problematic.) + /* If this block device already set up right, re-use it. + (Yes this is racy, but associating two loop devices with the same + file isn't pretty either. In general, mounting the same file twice + without using losetup manually is problematic.) + */ } else if(strcmp(file,loopinfo.lo_file_name) || offset!=loopinfo.lo_offset) rc=1; close(dfd); |