Unverified Commit ae18b940 authored by David Disseldorp's avatar David Disseldorp Committed by Nathan Chancellor
Browse files

gen_init_cpio: support -o <output_file> parameter 



This is another preparatory change to allow for reflink-optimized
cpio archives with file data written / cloned via copy_file_range().
The output file is truncated prior to write, so that it maps to
usr/gen_initramfs.sh usage. It may make sense to offer an append option
in future, for easier archive concatenation.

Signed-off-by: default avatarDavid Disseldorp <ddiss@suse.de>
Reviewed-by: default avatarNicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/r/20250819032607.28727-3-ddiss@suse.de


Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
parent 14002277

usr/gen_init_cpio.c

+16 −4
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#define _GNU_SOURCE

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>
@@ -110,7 +111,7 @@ static int cpio_trailer(void) 
	    push_pad(padlen(offset, 512)) < 0)

		return -1;



	return 0;

	return fsync(outfd);

}



static int cpio_mkslink(const char *name, const char *target,
@@ -532,7 +533,7 @@ static int cpio_mkfile_line(const char *line) 
static void usage(const char *prog)

{

	fprintf(stderr, "Usage:\n"

		"\t%s [-t <timestamp>] [-c] <cpio_list>\n"

		"\t%s [-t <timestamp>] [-c] [-o <output_file>] <cpio_list>\n"

		"\n"

		"<cpio_list> is a file containing newline separated entries that\n"

		"describe the files to be included in the initramfs archive:\n"
@@ -569,7 +570,8 @@ static void usage(const char *prog) 
		"as mtime for symlinks, directories, regular and special files.\n"

		"The default is to use the current time for all files, but\n"

		"preserve modification time for regular files.\n"

		"-c: calculate and store 32-bit checksums for file data.\n",

		"-c: calculate and store 32-bit checksums for file data.\n"

		"<output_file>: write cpio to this file instead of stdout\n",

		prog);

}
@@ -611,7 +613,7 @@ int main (int argc, char *argv[]) 


	default_mtime = time(NULL);

	while (1) {

		int opt = getopt(argc, argv, "t:ch");

		int opt = getopt(argc, argv, "t:cho:");

		char *invalid;



		if (opt == -1)
@@ -630,6 +632,16 @@ int main (int argc, char *argv[]) 
		case 'c':

			do_csum = true;

			break;

		case 'o':

			outfd = open(optarg,

				     O_WRONLY | O_CREAT | O_LARGEFILE | O_TRUNC,

				     0600);

			if (outfd < 0) {

				fprintf(stderr, "failed to open %s\n", optarg);

				usage(argv[0]);

				exit(1);

			}

			break;

		case 'h':

		case '?':

			usage(argv[0]);