From: Karel Zak <kzak@redhat.com>
Date: Mon, 14 Oct 2024 13:48:46 +0000 (+0200)
Subject: cfdisk: add --sector-size commanand line option
X-Git-Tag: v2.42-start~178
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fd38ee2274f7a30393d3839dfce556260355c3fa;p=thirdparty%2Futil-linux.git

cfdisk: add --sector-size commanand line option

* improves compatibility with fdisk
* add ability to work with disk images where libfdisk defaults to 512

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/disk-utils/cfdisk.8.adoc b/disk-utils/cfdisk.8.adoc
index 97fad621d..759f39f0e 100644
--- a/disk-utils/cfdisk.8.adoc
+++ b/disk-utils/cfdisk.8.adoc
@@ -55,6 +55,9 @@ Use exclusive BSD lock for device or file it operates. The optional argument _mo
 *-r*, *--read-only*::
 Forced open in read-only mode.
 
+*-b*, *--sector-size* _sectorsize_::
+Specify the sector size of the disk. Valid values are 512, 1024, 2048, and 4096. The kernel is aware of the sector size for regular block devices. Use this option only on very old kernels, when working with disk images, or to override the kernel's default sector size. Since util-linux-2.17, *fdisk* distinguishes between logical and physical sector size. This option changes both sector sizes to the specified _sectorsize_.
+
 *-z*, *--zero*::
 Start with an in-memory zeroed partition table. This option does not zero the partition table on the disk; rather, it simply starts the program without reading the existing partition table. This option allows you to create a new partition table from scratch or from an *sfdisk*(8)-compatible script.
 
diff --git a/disk-utils/cfdisk.c b/disk-utils/cfdisk.c
index 2e0aada47..bc1c87d83 100644
--- a/disk-utils/cfdisk.c
+++ b/disk-utils/cfdisk.c
@@ -2731,6 +2731,8 @@ static void __attribute__((__noreturn__)) usage(void)
 	      _("     --lock[=<mode>]      use exclusive device lock (%s, %s or %s)\n"), "yes", "no", "nonblock");
 	fputs(_(" -r, --read-only          forced open cfdisk in read-only mode\n"), out);
 
+	fputs(_(" -b, --sector-size <size> physical and logical sector size\n"), out);
+
 	fputs(USAGE_SEPARATOR, out);
 	fprintf(out, USAGE_HELP_OPTIONS(26));
 
@@ -2743,6 +2745,7 @@ int main(int argc, char *argv[])
 	const char *diskpath = NULL, *lockmode = NULL;
 	int rc, c, colormode = UL_COLORMODE_UNDEF;
 	int read_only = 0;
+	size_t user_ss = 0;
 	struct cfdisk _cf = { .lines_idx = 0 },
 		      *cf = &_cf;
 	enum {
@@ -2752,6 +2755,7 @@ int main(int argc, char *argv[])
 		{ "color",   optional_argument, NULL, 'L' },
 		{ "lock",    optional_argument, NULL, OPT_LOCK },
 		{ "help",    no_argument,       NULL, 'h' },
+		{ "sector-size", required_argument, NULL, 'b' },
 		{ "version", no_argument,       NULL, 'V' },
 		{ "zero",    no_argument,	NULL, 'z' },
 		{ "read-only", no_argument,     NULL, 'r' },
@@ -2763,8 +2767,15 @@ int main(int argc, char *argv[])
 	textdomain(PACKAGE);
 	close_stdout_atexit();
 
-	while((c = getopt_long(argc, argv, "L::hVzr", longopts, NULL)) != -1) {
+	while((c = getopt_long(argc, argv, "b:L::hVzr", longopts, NULL)) != -1) {
 		switch(c) {
+		case 'b':
+			user_ss = strtou32_or_err(optarg,
+					_("invalid sector size argument"));
+			if (user_ss != 512 && user_ss != 1024 &&
+			    user_ss != 2048 && user_ss != 4096)
+				errx(EXIT_FAILURE, _("invalid sector size argument"));
+			break;
 		case 'h':
 			usage();
 			break;
@@ -2803,6 +2814,8 @@ int main(int argc, char *argv[])
 	cf->cxt = fdisk_new_context();
 	if (!cf->cxt)
 		err(EXIT_FAILURE, _("failed to allocate libfdisk context"));
+	if (user_ss)
+		fdisk_save_user_sector_size(cf->cxt, user_ss, user_ss);
 
 	fdisk_set_ask(cf->cxt, ask_callback, (void *) cf);