X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=util-linux%2Flosetup.c;h=776f784f5b1a51b7b34789fe0f68525af81dea2d;hb=38292b68c962b9d470fa4e577020749c8c69226d;hp=e2d4e4d79162571f910ed09cd31ad41979eec091;hpb=b6adbf1be29841501cc49917249e85f273e1df7c;p=oweals%2Fbusybox.git

diff --git a/util-linux/losetup.c b/util-linux/losetup.c
index e2d4e4d79..776f784f5 100644
--- a/util-linux/losetup.c
+++ b/util-linux/losetup.c
@@ -4,63 +4,84 @@
  *
  * Copyright (C) 2002  Matt Kraai.
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include <getopt.h>
-
 #include "libbb.h"
 
-int losetup_main(int argc, char **argv);
-int losetup_main(int argc, char **argv)
+int losetup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int losetup_main(int argc UNUSED_PARAM, char **argv)
 {
 	unsigned opt;
+	int n;
 	char *opt_o;
 	unsigned long long offset = 0;
+	enum {
+		OPT_d = (1 << 0),
+		OPT_o = (1 << 1),
+		OPT_f = (1 << 2),
+	};
 
-	opt = getopt32(argc, argv, "do:", &opt_o);
-	argc -= optind;
+	/* max 2 args, all opts are mutually exclusive */
+	opt_complementary = "?2:d--of:o--df:f--do";
+	opt = getopt32(argv, "do:f", &opt_o);
 	argv += optind;
 
-	if (opt == 0x3) // -d + -o (illegal)
-		bb_show_usage();
+	if (opt == OPT_o)
+		offset = xatoull(opt_o);
 
-	if (opt == 0x1) { // -d
-		/* detach takes exactly one argument */
-		if (argc != 1)
+	if (opt == OPT_d) {
+		/* -d BLOCKDEV */
+		if (!argv[0] || argv[1])
 			bb_show_usage();
-		if (!del_loop(argv[0]))
-			return EXIT_SUCCESS;
-		bb_perror_nomsg_and_die();
+		if (del_loop(argv[0]))
+			bb_simple_perror_msg_and_die(argv[0]);
+		return EXIT_SUCCESS;
 	}
 
-	if (opt == 0x2) // -o
-		offset = xatoull(opt_o);
+	if (argv[0]) {
+		char *s;
 
-	/* -o or no option */
+		if (opt == OPT_f) /* -f should not have arguments */
+			bb_show_usage();
 
-	if (argc == 2) {
-		if (set_loop(&argv[0], argv[1], offset) < 0)
-			bb_perror_nomsg_and_die();
-	} else if (argc == 1) {
-		char *s = query_loop(argv[0]);
+		if (argv[1]) {
+			/* [-o OFS] BLOCKDEV FILE */
+			if (set_loop(&argv[0], argv[1], offset) < 0)
+				bb_simple_perror_msg_and_die(argv[0]);
+			return EXIT_SUCCESS;
+		}
+		/* [-o OFS] BLOCKDEV */
+		s = query_loop(argv[0]);
 		if (!s)
-			bb_perror_nomsg_and_die();
+			bb_simple_perror_msg_and_die(argv[0]);
 		printf("%s: %s\n", argv[0], s);
 		if (ENABLE_FEATURE_CLEAN_UP)
 			free(s);
-	} else {
-		char dev[sizeof(LOOP_NAME"0")] = LOOP_NAME"0";
-		char c;
-		for (c = '0'; c <= '9'; ++c) {
-			char *s;
-			dev[sizeof(LOOP_NAME"0")-2] = c;
-			s = query_loop(dev);
-			if (s) {
-				printf("%s: %s\n", dev, s);
-				if (ENABLE_FEATURE_CLEAN_UP)
-					free(s);
+		return EXIT_SUCCESS;
+	}
+
+	/* [-o OFS|-f] with no params */
+	n = 0;
+	while (1) {
+		char *s;
+		char dev[LOOP_NAMESIZE];
+
+		sprintf(dev, LOOP_FORMAT, n);
+		s = query_loop(dev);
+		n++;
+		if (!s) {
+			if (n > 9 && errno && errno != ENXIO)
+				return EXIT_SUCCESS;
+			if (opt == OPT_f) {
+				puts(dev);
+				return EXIT_SUCCESS;
 			}
+		} else {
+			if (opt != OPT_f)
+				printf("%s: %s\n", dev, s);
+			if (ENABLE_FEATURE_CLEAN_UP)
+				free(s);
 		}
 	}
 	return EXIT_SUCCESS;