From a3dc6a721873f0365612a5acee952a5f7d33853a Mon Sep 17 00:00:00 2001
From: Harald Hoyer <harald@redhat.com>
Date: Fri, 24 Jan 2014 15:27:51 +0100
Subject: [PATCH] add skipcpio utility
skipcpio skips a cpio archive at the beginning of a file.
It is used for skipping an early cpio archive for lsinitrd.
---
Makefile | 13 ++++-
skipcpio/skipcpio.c | 123 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 135 insertions(+), 1 deletion(-)
create mode 100644 skipcpio/skipcpio.c
diff --git a/Makefile b/Makefile
index e7da9484..5441d8f4 100644
--- a/Makefile
+++ b/Makefile
@@ -40,7 +40,7 @@ manpages = $(man1pages) $(man5pages) $(man7pages) $(man8pages)
.PHONY: install clean archive rpm testimage test all check AUTHORS doc dracut-version.sh
-all: dracut-version.sh dracut-install
+all: dracut-version.sh dracut-install skipcpio/skipcpio
DRACUT_INSTALL_OBJECTS = \
install/dracut-install.o \
@@ -61,8 +61,15 @@ install/dracut-install: $(DRACUT_INSTALL_OBJECTS)
dracut-install: install/dracut-install
ln -fs $< $@
+SKIPCPIO_OBJECTS= \
+ skipcpio/skipcpio.o
+
+skipcpio/skipcpio.o: skipcpio/skipcpio.c
+skipcpio/skipcpio: skipcpio/skipcpio.o
+
indent:
indent -i8 -nut -br -linux -l120 install/dracut-install.c
+ indent -i8 -nut -br -linux -l120 skipcpio/skipcpio.c
doc: $(manpages) dracut.html
@@ -136,6 +143,9 @@ endif
if [ -f install/dracut-install ]; then \
install -m 0755 install/dracut-install $(DESTDIR)$(pkglibdir)/dracut-install; \
fi
+ if [ -f skipcpio/skipcpio ]; then \
+ install -m 0755 skipcpio/skipcpio $(DESTDIR)$(pkglibdir)/skipcpio; \
+ fi
mkdir -p $(DESTDIR)${prefix}/lib/kernel/install.d
install -m 0755 50-dracut.install $(DESTDIR)${prefix}/lib/kernel/install.d/50-dracut.install
install -m 0755 51-dracut-rescue.install $(DESTDIR)${prefix}/lib/kernel/install.d/51-dracut-rescue.install
@@ -155,6 +165,7 @@ clean:
$(RM) dracut-*.rpm dracut-*.tar.bz2
$(RM) dracut-version.sh
$(RM) dracut-install install/dracut-install $(DRACUT_INSTALL_OBJECTS)
+ $(RM) skipcpio/skipcpio $(SKIPCPIO_OBJECTS)
$(RM) $(manpages) dracut.html
$(MAKE) -C test clean
diff --git a/skipcpio/skipcpio.c b/skipcpio/skipcpio.c
new file mode 100644
index 00000000..fbf391bf
--- /dev/null
+++ b/skipcpio/skipcpio.c
@@ -0,0 +1,123 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/* dracut-install.c -- install files and executables
+
+ Copyright (C) 2012 Harald Hoyer
+ Copyright (C) 2012 Red Hat, Inc. All rights reserved.
+
+ This program is free software: you can redistribute it and/or modify
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program; If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define PROGRAM_VERSION_STRING "1"
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#define CPIO_END "TRAILER!!!"
+#define CPIO_ENDLEN (sizeof(CPIO_END)-1)
+
+static char buf[CPIO_ENDLEN * 2 + 1];
+
+int main(int argc, char **argv)
+{
+ FILE *f;
+ size_t s;
+ long pos = 0;
+
+ if (argc != 2) {
+ fprintf(stderr, "Usage: %s <file>\n", argv[0]);
+ exit(1);
+ }
+
+ f = fopen(argv[1], "r");
+
+ if (f == NULL) {
+ fprintf(stderr, "Cannot open file '%s'\n", argv[1]);
+ exit(1);
+ }
+
+ s = fread(buf, 6, 1, f);
+ if (s <= 0) {
+ fprintf(stderr, "Read error from file '%s'\n", argv[1]);
+ fclose(f);
+ exit(1);
+ }
+ fseek(f, 0, SEEK_SET);
+
+ /* check, if this is a cpio archive */
+ if ((buf[0] == 0x71 && buf[1] == 0xc7)
+ || (buf[0] == '0' && buf[1] == '7' && buf[0] == '0' && buf[1] == '7' && buf[0] == '0' && buf[1] == '1')) {
+
+ /* Search for CPIO_END */
+ do {
+ char *h;
+ fseek(f, pos, SEEK_SET);
+ buf[sizeof(buf) - 1] = 0;
+ s = fread(buf, CPIO_ENDLEN, 2, f);
+ if (s <= 0)
+ break;
+
+ h = strstr(buf, CPIO_END);
+ if (h) {
+ pos = (h - buf) + pos + CPIO_ENDLEN;
+ fseek(f, pos, SEEK_SET);
+ break;
+ }
+ pos += CPIO_ENDLEN;
+ } while (!feof(f));
+
+ if (feof(f)) {
+ /* CPIO_END not found, just cat the whole file */
+ fseek(f, 0, SEEK_SET);
+ } else {
+ /* skip zeros */
+ while (!feof(f)) {
+ size_t i;
+
+ buf[sizeof(buf) - 1] = 0;
+ s = fread(buf, 1, sizeof(buf) - 1, f);
+ if (s <= 0)
+ break;
+
+ for (i = 0; (i < s) && (buf[i] == 0); i++) ;
+
+ if (buf[i] != 0) {
+ pos += i;
+ fseek(f, pos, SEEK_SET);
+ break;
+ }
+
+ pos += s;
+ }
+ }
+ }
+ /* cat out the rest */
+ while (!feof(f)) {
+ s = fread(buf, 1, sizeof(buf), f);
+ if (s <= 0)
+ break;
+
+ s = fwrite(buf, 1, s, stdout);
+ if (s <= 0)
+ break;
+ }
+ fclose(f);
+}