From 726cbb1be8620496cdf05d23bd98bdeb0983b4f0 Mon Sep 17 00:00:00 2001 From: Jack O'Sullivan Date: Tue, 28 May 2019 15:28:27 +0100 Subject: [PATCH] losetup: Add partition scanning option Add -P option from util-linux losetup to scan for partitions. function old new delta losetup_main 449 482 +33 packed_usage 33264 33292 +28 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 2/0 up/down: 61/0) Total: 61 bytes Signed-off-by: Jack O'Sullivan Signed-off-by: Denys Vlasenko --- include/libbb.h | 1 + util-linux/losetup.c | 27 +++++++++++++++++---------- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/include/libbb.h b/include/libbb.h index 33766e989..3a870bf80 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -1471,6 +1471,7 @@ extern int set_loop(char **devname, const char *file, unsigned long long offset, /* These constants match linux/loop.h (without BB_ prefix): */ #define BB_LO_FLAGS_READ_ONLY 1 #define BB_LO_FLAGS_AUTOCLEAR 4 +#define BB_LO_FLAGS_PARTSCAN 8 /* Returns malloced str */ char *bb_ask_noecho(int fd, int timeout, const char *prompt) FAST_FUNC; diff --git a/util-linux/losetup.c b/util-linux/losetup.c index 2248f2cba..b52d693ec 100644 --- a/util-linux/losetup.c +++ b/util-linux/losetup.c @@ -20,13 +20,14 @@ //kbuild:lib-$(CONFIG_LOSETUP) += losetup.o //usage:#define losetup_trivial_usage -//usage: "[-r] [-o OFS] {-f|LOOPDEV} FILE: associate loop devices\n" +//usage: "[-rP] [-o OFS] {-f|LOOPDEV} FILE: associate loop devices\n" //usage: " losetup -c LOOPDEV: reread file size\n" //usage: " losetup -d LOOPDEV: disassociate\n" //usage: " losetup -a: show status\n" //usage: " losetup -f: show next free loop device" //usage:#define losetup_full_usage "\n\n" //usage: " -o OFS Start OFS bytes into FILE" +//usage: "\n -P Scan for partitions" //usage: "\n -r Read-only" //usage: "\n -f Show/use next free loop device" //usage: @@ -35,8 +36,9 @@ //usage: "(if any), or disassociate it (with -d). The display shows the offset\n" //usage: "and filename of the file the loop device is currently bound to.\n\n" //usage: "Two arguments (losetup /dev/loop1 file.img) create a new association,\n" -//usage: "with an optional offset (-o 12345). Encryption is not yet supported.\n" -//usage: "losetup -f will show the first loop free loop device\n\n" +//usage: "with optional partition scanning (creates /dev/loop1p1, /dev/loop1p2\n" +//usage: "etc. with -P) and with an optional offset (-o 12345). Encryption is\n" +//usage: "not yet supported. losetup -f will show the first free loop device\n\n" #include "libbb.h" @@ -53,13 +55,14 @@ int losetup_main(int argc UNUSED_PARAM, char **argv) enum { OPT_c = (1 << 0), OPT_d = (1 << 1), - OPT_o = (1 << 2), - OPT_f = (1 << 3), - OPT_a = (1 << 4), - OPT_r = (1 << 5), + OPT_P = (1 << 2), + OPT_o = (1 << 3), + OPT_f = (1 << 4), + OPT_a = (1 << 5), + OPT_r = (1 << 6), }; - opt = getopt32(argv, "^" "cdo:far" "\0" "?2:d--ofar:a--ofr", &opt_o); + opt = getopt32(argv, "^" "cdPo:far" "\0" "?2:d--Pofar:a--Pofr", &opt_o); argv += optind; /* LOOPDEV */ @@ -127,7 +130,7 @@ int losetup_main(int argc UNUSED_PARAM, char **argv) } } - /* [-r] [-o OFS] {-f|LOOPDEV} FILE */ + /* [-rP] [-o OFS] {-f|LOOPDEV} FILE */ if (argv[0] && ((opt & OPT_f) || argv[1])) { unsigned long long offset = 0; char *d = dev; @@ -138,7 +141,11 @@ int losetup_main(int argc UNUSED_PARAM, char **argv) d = *argv++; if (argv[0]) { - if (set_loop(&d, argv[0], offset, (opt & OPT_r) ? BB_LO_FLAGS_READ_ONLY : 0) < 0) + unsigned flags = (opt & OPT_r) ? BB_LO_FLAGS_READ_ONLY : 0; + if (opt & OPT_P) { + flags |= BB_LO_FLAGS_PARTSCAN; + } + if (set_loop(&d, argv[0], offset, flags) < 0) bb_simple_perror_msg_and_die(argv[0]); return EXIT_SUCCESS; } -- 2.25.1