1 files changed, 128 insertions, 0 deletions
diff --git a/libbb/loop.c b/libbb/loop.c
new file mode 100644
index 0000000..4754b8d
--- /dev/null
+++ b/libbb/loop.c
@@ -0,0 +1,128 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) tons of folks.  Tracking down who wrote what
+ * isn't something I'm going to worry about...  If you wrote something
+ * here, please feel free to acknowledge your work.
+ *
+ * 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
+ *
+ * Based in part on code from sash, Copyright (c) 1999 by David I. Bell 
+ * Permission has been granted to redistribute this code under the GPL.
+ *
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include "libbb.h"
+#include "loop.h" /* Pull in loop device support */
+
+extern int del_loop(const char *device)
+{
+	int fd;
+
+	if ((fd = open(device, O_RDONLY)) < 0) {
+		perror_msg("%s", device);
+		return (FALSE);
+	}
+	if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
+		perror_msg("ioctl: LOOP_CLR_FD");
+		return (FALSE);
+	}
+	close(fd);
+	return (TRUE);
+}
+
+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_msg("%s", file);
+		return 1;
+	}
+	if ((fd = open(device, mode)) < 0) {
+		close(ffd);
+		perror_msg("%s", device);
+		return 1;
+	}
+	*loopro = (mode == O_RDONLY);
+
+	memset(&loopinfo, 0, sizeof(loopinfo));
+	safe_strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
+
+	loopinfo.lo_offset = offset;
+
+	loopinfo.lo_encrypt_key_size = 0;
+	if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
+		perror_msg("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_msg("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) != 0) {
+					if (errno == ENXIO) {	/* probably free */
+						close(fd);
+						return strdup(dev);
+					}
+				}
+				close(fd);
+			}
+		}
+	}
+	return NULL;
+}
+
+
+/* END CODE */
+/*
+Local Variables:
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/