Initial revision0_29alpha2

1 files changed, 190 insertions, 0 deletions

diff --git a/losetup.c b/losetup.c
new file mode 100644
index 0000000..2908dbc
--- /dev/null
+++ b/losetup.c
@@ -0,0 +1,190 @@
+/*
+ * losetup.c - setup and control loop devices
+ */
+
+
+#include "internal.h"
+
+const char	losetup_usage[] = "losetup\n"
+"\n"
+"\tlosetup loop_device				give info\n"
+"\tlosetup -d loop_device				delete\n"
+"\tlosetup [ -o offset ] loop_device file		setup\n";
+
+/* from mount-2.6d */
+
+/*
+ * losetup.c - setup and control loop devices
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+/* #include "loop.h" */
+
+/*
+ * include/linux/loop.h
+ *
+ * Written by Theodore Ts'o, 3/29/93.
+ *
+ * Copyright 1993 by Theodore Ts'o.  Redistribution of this file is
+ * permitted under the GNU Public License.
+ */
+
+#define LO_NAME_SIZE	64
+#define LO_KEY_SIZE	32
+       
+struct loop_info {
+	int		lo_number;	/* ioctl r/o */
+	dev_t		lo_device; 	/* ioctl r/o */
+	unsigned long	lo_inode; 	/* ioctl r/o */
+	dev_t		lo_rdevice; 	/* ioctl r/o */
+	int		lo_offset;
+	int		lo_encrypt_type;
+	int		lo_encrypt_key_size; 	/* ioctl w/o */
+	int		lo_flags;	/* ioctl r/o */
+	char		lo_name[LO_NAME_SIZE];
+	unsigned char	lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+	unsigned long	lo_init[2];
+	char		reserved[4];
+};
+
+/*
+ * IOCTL commands --- we will commandeer 0x4C ('L')
+ */
+
+#define LOOP_SET_FD	0x4C00
+#define LOOP_CLR_FD	0x4C01
+#define LOOP_SET_STATUS	0x4C02
+#define LOOP_GET_STATUS	0x4C03
+
+/* #include "lomount.h" */
+
+extern int set_loop (const char *, const char *, int, int *);
+extern int del_loop (const char *);
+
+static void show_loop(const char *device)
+{
+	struct	loop_info	loopinfo;
+	int			fd;
+	
+	if ((fd = open(device, O_RDWR)) < 0) {
+		perror(device);
+		return;
+	}
+	if (ioctl(fd, LOOP_GET_STATUS, &loopinfo) < 0) {
+		perror("Cannot get loop info");
+		close(fd);
+		return;
+	}
+	printf("%s: [%04x]:%ld (%s) offset %d\n",
+	       device, (unsigned int)loopinfo.lo_device, loopinfo.lo_inode,
+	       loopinfo.lo_name, loopinfo.lo_offset);
+	close(fd);
+}
+
+
+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");
+		exit(1);
+	}
+	if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
+		(void) ioctl(fd, LOOP_CLR_FD, 0);
+		perror("ioctl: LOOP_SET_STATUS");
+		exit(1);
+	}
+	close(fd);
+	close(ffd);
+	return 0;
+}
+
+int del_loop(const char *device)
+{
+	int fd;
+
+	if ((fd = open(device, O_RDONLY)) < 0) {
+		perror(device);
+		exit(1);
+	}
+	if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
+		perror("ioctl: LOOP_CLR_FD");
+		exit(1);
+	}
+	close(fd);
+	return(0);
+}
+
+
+static int losetup_usage_fn(void)
+{
+	fprintf(stderr, losetup_usage);
+	exit(1);
+}
+
+int losetup_main(struct FileInfo * i, int argc, char * * argv)
+{
+	char *offset;
+	int delete,off,c;
+	int ro = 0;
+
+	delete = off = 0;
+	offset = NULL;
+	while ((c = getopt(argc,argv,"do:")) != EOF) {
+		switch (c) {
+			case 'd':
+				delete = 1;
+				break;
+			case 'o':
+				offset = optarg;
+				break;
+			default:
+				losetup_usage_fn();
+		}
+	}
+	if (argc == 1) losetup_usage_fn();
+	if ((delete && (argc != optind+1 || offset)) ||
+	    (!delete && (argc < optind+1 || argc > optind+2)))
+		losetup_usage_fn();
+	if (argc == optind+1)
+		if (delete)
+			del_loop(argv[optind]);
+		else
+			show_loop(argv[optind]);
+	else {
+		if (offset && sscanf(offset,"%d",&off) != 1)
+			losetup_usage_fn();
+		set_loop(argv[optind],argv[optind+1],off,&ro);
+	}
+	return 0;
+}