SDK: init

4 files changed, 1143 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b6f8ad5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+gen_init_cpio
+gen_init_cpio.o
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..227b449
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
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+    This program is free software; you can redistribute it and/or modify
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+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Moe Ghoul>, 1 April 1989
+  Moe Ghoul, President of Vice
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+This General Public License does not permit incorporating your program into
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+
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..6435ad7
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+CC = gcc
+LDFLAGS = -no-pie -g
+
+.PHONY: all clean
+
+all: gen_init_cpio
+
+%.o: %.c
+	$(CC) -o $@ -c $<
+
+gen_init_cpio: gen_init_cpio.o
+	$(CC) -o $@ $^ $(LDFLAGS)
+
+clean:
+	rm -rf $(OBJ) gen_init_cpio.o gen_init_cpio
+
diff --git a/gen_init_cpio.c b/gen_init_cpio.c
new file mode 100644
index 0000000..694b88c
--- /dev/null
+++ b/gen_init_cpio.c
@@ -0,0 +1,786 @@
+/* From git repository torvalds/linux, redistributed under
+   the terms of the GNU Public License 2.0
+
+   Commit 38492c5743f8b7213ca86f0cd72ea625af35d5ef */
+
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
+
+/*
+ * Original work by Jeff Garzik
+ *
+ * External file lists, symlink, pipe and fifo support by Thayne Harbaugh
+ * Hard link support by Luciano Rocha
+ */
+
+#define xstr(s) #s
+#define str(s) xstr(s)
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#define CPIO_HDR_LEN 110
+#define CPIO_TRAILER "TRAILER!!!"
+#define padlen(_off, _align) (((_align) - ((_off) & ((_align) - 1))) % (_align))
+
+/* zero-padding the filename field for data alignment is limited by PATH_MAX */
+static char padding[PATH_MAX];
+static unsigned int offset;
+static unsigned int ino = 721;
+static time_t default_mtime;
+static bool do_file_mtime;
+static bool do_csum = false;
+static int outfd = STDOUT_FILENO;
+static unsigned int dalign;
+
+struct file_handler {
+	const char *type;
+	int (*handler)(const char *line);
+};
+
+static int push_buf(const char *name, size_t name_len)
+{
+	ssize_t len;
+
+	len = write(outfd, name, name_len);
+	if (len != name_len)
+		return -1;
+
+	offset += name_len;
+	return 0;
+}
+
+static int push_pad(size_t padlen)
+{
+	ssize_t len = 0;
+
+	if (!padlen)
+		return 0;
+
+	if (padlen < sizeof(padding))
+		len = write(outfd, padding, padlen);
+	if (len != padlen)
+		return -1;
+
+	offset += padlen;
+	return 0;
+}
+
+static int push_rest(const char *name, size_t name_len)
+{
+	ssize_t len;
+
+	len = write(outfd, name, name_len);
+	if (len != name_len)
+		return -1;
+
+	offset += name_len;
+
+	return push_pad(padlen(name_len + CPIO_HDR_LEN, 4));
+}
+
+static int cpio_trailer(void)
+{
+	int len;
+	unsigned int namesize = sizeof(CPIO_TRAILER);
+
+	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"
+	       "%08X%08X%08X%08X%08X%08X%08X",
+		do_csum ? "070702" : "070701", /* magic */
+		0,			/* ino */
+		0,			/* mode */
+		(long) 0,		/* uid */
+		(long) 0,		/* gid */
+		1,			/* nlink */
+		(long) 0,		/* mtime */
+		0,			/* filesize */
+		0,			/* major */
+		0,			/* minor */
+		0,			/* rmajor */
+		0,			/* rminor */
+		namesize,		/* namesize */
+		0);			/* chksum */
+	offset += len;
+
+	if (len != CPIO_HDR_LEN ||
+	    push_rest(CPIO_TRAILER, namesize) < 0 ||
+	    push_pad(padlen(offset, 512)) < 0)
+		return -1;
+
+	if (fsync(outfd) < 0 && errno != EINVAL)
+		return -1;
+
+	return 0;
+}
+
+static int cpio_mkslink(const char *name, const char *target,
+			 unsigned int mode, uid_t uid, gid_t gid)
+{
+	int len;
+	unsigned int namesize, targetsize = strlen(target) + 1;
+
+	if (name[0] == '/')
+		name++;
+	namesize = strlen(name) + 1;
+
+	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"
+	       "%08X%08X%08X%08X%08X%08X%08X",
+		do_csum ? "070702" : "070701", /* magic */
+		ino++,			/* ino */
+		S_IFLNK | mode,		/* mode */
+		(long) uid,		/* uid */
+		(long) gid,		/* gid */
+		1,			/* nlink */
+		(long) default_mtime,	/* mtime */
+		targetsize,		/* filesize */
+		3,			/* major */
+		1,			/* minor */
+		0,			/* rmajor */
+		0,			/* rminor */
+		namesize,		/* namesize */
+		0);			/* chksum */
+	offset += len;
+
+	if (len != CPIO_HDR_LEN ||
+	    push_buf(name, namesize) < 0 ||
+	    push_pad(padlen(offset, 4)) < 0 ||
+	    push_buf(target, targetsize) < 0 ||
+	    push_pad(padlen(offset, 4)) < 0)
+		return -1;
+
+	return 0;
+
+}
+
+static int cpio_mkslink_line(const char *line)
+{
+	char name[PATH_MAX + 1];
+	char target[PATH_MAX + 1];
+	unsigned int mode;
+	int uid;
+	int gid;
+	int rc = -1;
+
+	if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) {
+		fprintf(stderr, "Unrecognized dir format '%s'", line);
+		goto fail;
+	}
+	rc = cpio_mkslink(name, target, mode, uid, gid);
+ fail:
+	return rc;
+}
+
+static int cpio_mkgeneric(const char *name, unsigned int mode,
+		       uid_t uid, gid_t gid)
+{
+	int len;
+	unsigned int namesize;
+
+	if (name[0] == '/')
+		name++;
+	namesize = strlen(name) + 1;
+
+	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"
+	       "%08X%08X%08X%08X%08X%08X%08X",
+		do_csum ? "070702" : "070701", /* magic */
+		ino++,			/* ino */
+		mode,			/* mode */
+		(long) uid,		/* uid */
+		(long) gid,		/* gid */
+		2,			/* nlink */
+		(long) default_mtime,	/* mtime */
+		0,			/* filesize */
+		3,			/* major */
+		1,			/* minor */
+		0,			/* rmajor */
+		0,			/* rminor */
+		namesize,		/* namesize */
+		0);			/* chksum */
+	offset += len;
+
+	if (len != CPIO_HDR_LEN ||
+	    push_rest(name, namesize) < 0)
+		return -1;
+
+	return 0;
+}
+
+enum generic_types {
+	GT_DIR,
+	GT_PIPE,
+	GT_SOCK
+};
+
+struct generic_type {
+	const char *type;
+	mode_t mode;
+};
+
+static const struct generic_type generic_type_table[] = {
+	[GT_DIR] = {
+		.type = "dir",
+		.mode = S_IFDIR
+	},
+	[GT_PIPE] = {
+		.type = "pipe",
+		.mode = S_IFIFO
+	},
+	[GT_SOCK] = {
+		.type = "sock",
+		.mode = S_IFSOCK
+	}
+};
+
+static int cpio_mkgeneric_line(const char *line, enum generic_types gt)
+{
+	char name[PATH_MAX + 1];
+	unsigned int mode;
+	int uid;
+	int gid;
+	int rc = -1;
+
+	if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) {
+		fprintf(stderr, "Unrecognized %s format '%s'",
+			line, generic_type_table[gt].type);
+		goto fail;
+	}
+	mode |= generic_type_table[gt].mode;
+	rc = cpio_mkgeneric(name, mode, uid, gid);
+ fail:
+	return rc;
+}
+
+static int cpio_mkdir_line(const char *line)
+{
+	return cpio_mkgeneric_line(line, GT_DIR);
+}
+
+static int cpio_mkpipe_line(const char *line)
+{
+	return cpio_mkgeneric_line(line, GT_PIPE);
+}
+
+static int cpio_mksock_line(const char *line)
+{
+	return cpio_mkgeneric_line(line, GT_SOCK);
+}
+
+static int cpio_mknod(const char *name, unsigned int mode,
+		       uid_t uid, gid_t gid, char dev_type,
+		       unsigned int maj, unsigned int min)
+{
+	int len;
+	unsigned int namesize;
+
+	if (dev_type == 'b')
+		mode |= S_IFBLK;
+	else
+		mode |= S_IFCHR;
+
+	if (name[0] == '/')
+		name++;
+	namesize = strlen(name) + 1;
+
+	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"
+	       "%08X%08X%08X%08X%08X%08X%08X",
+		do_csum ? "070702" : "070701", /* magic */
+		ino++,			/* ino */
+		mode,			/* mode */
+		(long) uid,		/* uid */
+		(long) gid,		/* gid */
+		1,			/* nlink */
+		(long) default_mtime,	/* mtime */
+		0,			/* filesize */
+		3,			/* major */
+		1,			/* minor */
+		maj,			/* rmajor */
+		min,			/* rminor */
+		namesize,		/* namesize */
+		0);			/* chksum */
+	offset += len;
+
+	if (len != CPIO_HDR_LEN ||
+	    push_rest(name, namesize) < 0)
+		return -1;
+
+	return 0;
+}
+
+static int cpio_mknod_line(const char *line)
+{
+	char name[PATH_MAX + 1];
+	unsigned int mode;
+	int uid;
+	int gid;
+	char dev_type;
+	unsigned int maj;
+	unsigned int min;
+	int rc = -1;
+
+	if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u",
+			 name, &mode, &uid, &gid, &dev_type, &maj, &min)) {
+		fprintf(stderr, "Unrecognized nod format '%s'", line);
+		goto fail;
+	}
+	rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min);
+ fail:
+	return rc;
+}
+
+static int cpio_mkfile_csum(int fd, unsigned long size, uint32_t *csum)
+{
+	while (size) {
+		unsigned char filebuf[65536];
+		ssize_t this_read;
+		size_t i, this_size = MIN(size, sizeof(filebuf));
+
+		this_read = read(fd, filebuf, this_size);
+		if (this_read <= 0 || this_read > this_size)
+			return -1;
+
+		for (i = 0; i < this_read; i++)
+			*csum += filebuf[i];
+
+		size -= this_read;
+	}
+	/* seek back to the start for data segment I/O */
+	if (lseek(fd, 0, SEEK_SET) < 0)
+		return -1;
+
+	return 0;
+}
+
+static int cpio_mkfile(const char *name, const char *location,
+			unsigned int mode, uid_t uid, gid_t gid,
+			unsigned int nlinks)
+{
+	struct stat buf;
+	unsigned long size;
+	int file, retval, len;
+	int rc = -1;
+	time_t mtime;
+	int namesize, namepadlen;
+	unsigned int i;
+	uint32_t csum = 0;
+	ssize_t this_read;
+
+	mode |= S_IFREG;
+
+	file = open (location, O_RDONLY);
+	if (file < 0) {
+		fprintf (stderr, "File %s could not be opened for reading\n", location);
+		goto error;
+	}
+
+	retval = fstat(file, &buf);
+	if (retval) {
+		fprintf(stderr, "File %s could not be stat()'ed\n", location);
+		goto error;
+	}
+
+	if (do_file_mtime) {
+		mtime = default_mtime;
+	} else {
+		mtime = buf.st_mtime;
+		if (mtime > 0xffffffff) {
+			fprintf(stderr, "%s: Timestamp exceeds maximum cpio timestamp, clipping.\n",
+					location);
+			mtime = 0xffffffff;
+		}
+
+		if (mtime < 0) {
+			fprintf(stderr, "%s: Timestamp negative, clipping.\n",
+					location);
+			mtime = 0;
+		}
+	}
+
+	if (buf.st_size > 0xffffffff) {
+		fprintf(stderr, "%s: Size exceeds maximum cpio file size\n",
+			location);
+		goto error;
+	}
+
+	if (do_csum && cpio_mkfile_csum(file, buf.st_size, &csum) < 0) {
+		fprintf(stderr, "Failed to checksum file %s\n", location);
+		goto error;
+	}
+
+	size = 0;
+	namepadlen = 0;
+	for (i = 1; i <= nlinks; i++) {
+		if (name[0] == '/')
+			name++;
+		namesize = strlen(name) + 1;
+
+		/* data goes on last link, after any alignment padding */
+		if (i == nlinks)
+			size = buf.st_size;
+
+		if (dalign && size > dalign) {
+			namepadlen = padlen(offset + CPIO_HDR_LEN + namesize,
+					    dalign);
+			if (namesize + namepadlen > PATH_MAX) {
+				fprintf(stderr,
+					"%s: best-effort alignment %u missed\n",
+					name, dalign);
+				namepadlen = 0;
+			}
+		}
+
+		len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"
+		       "%08lX%08X%08X%08X%08X%08X%08X",
+			do_csum ? "070702" : "070701", /* magic */
+			ino,			/* ino */
+			mode,			/* mode */
+			(long) uid,		/* uid */
+			(long) gid,		/* gid */
+			nlinks,			/* nlink */
+			(long) mtime,		/* mtime */
+			size,			/* filesize */
+			3,			/* major */
+			1,			/* minor */
+			0,			/* rmajor */
+			0,			/* rminor */
+			namesize + namepadlen,	/* namesize */
+			size ? csum : 0);	/* chksum */
+		offset += len;
+
+		if (len != CPIO_HDR_LEN ||
+		    push_buf(name, namesize) < 0 ||
+		    push_pad(namepadlen ? namepadlen : padlen(offset, 4)) < 0)
+			goto error;
+
+		if (size) {
+			this_read = copy_file_range(file, NULL, outfd, NULL, size, 0);
+			if (this_read > 0) {
+				if (this_read > size)
+					goto error;
+				offset += this_read;
+				size -= this_read;
+			}
+			/* short or failed copy falls back to read/write... */
+		}
+
+		while (size) {
+			unsigned char filebuf[65536];
+			size_t this_size = MIN(size, sizeof(filebuf));
+
+			this_read = read(file, filebuf, this_size);
+			if (this_read <= 0 || this_read > this_size) {
+				fprintf(stderr, "Can not read %s file\n", location);
+				goto error;
+			}
+
+			if (write(outfd, filebuf, this_read) != this_read) {
+				fprintf(stderr, "writing filebuf failed\n");
+				goto error;
+			}
+			offset += this_read;
+			size -= this_read;
+		}
+		if (push_pad(padlen(offset, 4)) < 0)
+			goto error;
+
+		name += namesize;
+	}
+	ino++;
+	rc = 0;
+
+error:
+	if (file >= 0)
+		close(file);
+	return rc;
+}
+
+static char *cpio_replace_env(char *new_location)
+{
+	char expanded[PATH_MAX + 1];
+	char *start, *end, *var;
+
+	while ((start = strstr(new_location, "${")) &&
+	       (end = strchr(start + 2, '}'))) {
+		*start = *end = 0;
+		var = getenv(start + 2);
+		snprintf(expanded, sizeof expanded, "%s%s%s",
+			 new_location, var ? var : "", end + 1);
+		strcpy(new_location, expanded);
+	}
+
+	return new_location;
+}
+
+static int cpio_mkfile_line(const char *line)
+{
+	char name[PATH_MAX + 1];
+	char *dname = NULL; /* malloc'ed buffer for hard links */
+	char location[PATH_MAX + 1];
+	unsigned int mode;
+	int uid;
+	int gid;
+	int nlinks = 1;
+	int end = 0, dname_len = 0;
+	int rc = -1;
+
+	if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX)
+				"s %o %d %d %n",
+				name, location, &mode, &uid, &gid, &end)) {
+		fprintf(stderr, "Unrecognized file format '%s'", line);
+		goto fail;
+	}
+	if (end && isgraph(line[end])) {
+		int len;
+		int nend;
+
+		dname = malloc(strlen(line));
+		if (!dname) {
+			fprintf (stderr, "out of memory (%d)\n", dname_len);
+			goto fail;
+		}
+
+		dname_len = strlen(name) + 1;
+		memcpy(dname, name, dname_len);
+
+		do {
+			nend = 0;
+			if (sscanf(line + end, "%" str(PATH_MAX) "s %n",
+					name, &nend) < 1)
+				break;
+			len = strlen(name) + 1;
+			memcpy(dname + dname_len, name, len);
+			dname_len += len;
+			nlinks++;
+			end += nend;
+		} while (isgraph(line[end]));
+	} else {
+		dname = name;
+	}
+	rc = cpio_mkfile(dname, cpio_replace_env(location),
+	                 mode, uid, gid, nlinks);
+ fail:
+	if (dname_len) free(dname);
+	return rc;
+}
+
+static void usage(const char *prog)
+{
+	fprintf(stderr, "Usage:\n"
+		"\t%s [-t <timestamp>] [-c] [-o <output_file>] [-a <data_align>] <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"
+		"\n"
+		"# a comment\n"
+		"file <name> <location> <mode> <uid> <gid> [<hard links>]\n"
+		"dir <name> <mode> <uid> <gid>\n"
+		"nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
+		"slink <name> <target> <mode> <uid> <gid>\n"
+		"pipe <name> <mode> <uid> <gid>\n"
+		"sock <name> <mode> <uid> <gid>\n"
+		"\n"
+		"<name>       name of the file/dir/nod/etc in the archive\n"
+		"<location>   location of the file in the current filesystem\n"
+		"             expands shell variables quoted with ${}\n"
+		"<target>     link target\n"
+		"<mode>       mode/permissions of the file\n"
+		"<uid>        user id (0=root)\n"
+		"<gid>        group id (0=root)\n"
+		"<dev_type>   device type (b=block, c=character)\n"
+		"<maj>        major number of nod\n"
+		"<min>        minor number of nod\n"
+		"<hard links> space separated list of other links to file\n"
+		"\n"
+		"example:\n"
+		"# A simple initramfs\n"
+		"dir /dev 0755 0 0\n"
+		"nod /dev/console 0600 0 0 c 5 1\n"
+		"dir /root 0700 0 0\n"
+		"dir /sbin 0755 0 0\n"
+		"file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n"
+		"\n"
+		"<timestamp> is time in seconds since Epoch that will be used\n"
+		"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"
+		"<output_file>: write cpio to this file instead of stdout\n"
+		"<data_align>: attempt to align file data by zero-padding the\n"
+		"filename field up to data_align. Must be a multiple of 4.\n"
+		"Alignment is best-effort; PATH_MAX limits filename padding.\n",
+		prog);
+}
+
+static const struct file_handler file_handler_table[] = {
+	{
+		.type    = "file",
+		.handler = cpio_mkfile_line,
+	}, {
+		.type    = "nod",
+		.handler = cpio_mknod_line,
+	}, {
+		.type    = "dir",
+		.handler = cpio_mkdir_line,
+	}, {
+		.type    = "slink",
+		.handler = cpio_mkslink_line,
+	}, {
+		.type    = "pipe",
+		.handler = cpio_mkpipe_line,
+	}, {
+		.type    = "sock",
+		.handler = cpio_mksock_line,
+	}, {
+		.type    = NULL,
+		.handler = NULL,
+	}
+};
+
+#define LINE_SIZE (2 * PATH_MAX + 50)
+
+int main (int argc, char *argv[])
+{
+	FILE *cpio_list;
+	char line[LINE_SIZE];
+	char *args, *type;
+	int ec = 0;
+	int line_nr = 0;
+	const char *filename;
+
+	default_mtime = time(NULL);
+	while (1) {
+		int opt = getopt(argc, argv, "t:cho:a:");
+		char *invalid;
+
+		if (opt == -1)
+			break;
+		switch (opt) {
+		case 't':
+			default_mtime = strtol(optarg, &invalid, 10);
+			if (!*optarg || *invalid) {
+				fprintf(stderr, "Invalid timestamp: %s\n",
+						optarg);
+				usage(argv[0]);
+				exit(1);
+			}
+			do_file_mtime = true;
+			break;
+		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 'a':
+			dalign = strtoul(optarg, &invalid, 10);
+			if (!*optarg || *invalid || (dalign & 3)) {
+				fprintf(stderr, "Invalid data_align: %s\n",
+						optarg);
+				usage(argv[0]);
+				exit(1);
+			}
+			break;
+		case 'h':
+		case '?':
+			usage(argv[0]);
+			exit(opt == 'h' ? 0 : 1);
+		}
+	}
+
+	/*
+	 * Timestamps after 2106-02-07 06:28:15 UTC have an ascii hex time_t
+	 * representation that exceeds 8 chars and breaks the cpio header
+	 * specification. Negative timestamps similarly exceed 8 chars.
+	 */
+	if (default_mtime > 0xffffffff || default_mtime < 0) {
+		fprintf(stderr, "ERROR: Timestamp out of range for cpio format\n");
+		exit(1);
+	}
+
+	if (argc - optind != 1) {
+		usage(argv[0]);
+		exit(1);
+	}
+	filename = argv[optind];
+	if (!strcmp(filename, "-"))
+		cpio_list = stdin;
+	else if (!(cpio_list = fopen(filename, "r"))) {
+		fprintf(stderr, "ERROR: unable to open '%s': %s\n\n",
+			filename, strerror(errno));
+		usage(argv[0]);
+		exit(1);
+	}
+
+	while (fgets(line, LINE_SIZE, cpio_list)) {
+		int type_idx;
+		size_t slen = strlen(line);
+
+		line_nr++;
+
+		if ('#' == *line) {
+			/* comment - skip to next line */
+			continue;
+		}
+
+		if (! (type = strtok(line, " \t"))) {
+			fprintf(stderr,
+				"ERROR: incorrect format, could not locate file type line %d: '%s'\n",
+				line_nr, line);
+			ec = -1;
+			break;
+		}
+
+		if ('\n' == *type) {
+			/* a blank line */
+			continue;
+		}
+
+		if (slen == strlen(type)) {
+			/* must be an empty line */
+			continue;
+		}
+
+		if (! (args = strtok(NULL, "\n"))) {
+			fprintf(stderr,
+				"ERROR: incorrect format, newline required line %d: '%s'\n",
+				line_nr, line);
+			ec = -1;
+		}
+
+		for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) {
+			int rc;
+			if (! strcmp(line, file_handler_table[type_idx].type)) {
+				if ((rc = file_handler_table[type_idx].handler(args))) {
+					ec = rc;
+					fprintf(stderr, " line %d\n", line_nr);
+				}
+				break;
+			}
+		}
+
+		if (NULL == file_handler_table[type_idx].type) {
+			fprintf(stderr, "unknown file type line %d: '%s'\n",
+				line_nr, line);
+		}
+	}
+	if (ec == 0)
+		ec = cpio_trailer();
+
+	exit(ec);
+}