Split generic tar code off to static library

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

5 files changed, 4 insertions, 780 deletions

diff --git a/tar/Makemodule.am b/tar/Makemodule.am
index 6c9edc7..a10dc01 100644
--- a/tar/Makemodule.am
+++ b/tar/Makemodule.am
@@ -1,9 +1,9 @@
-sqfs2tar_SOURCES = tar/sqfs2tar.c tar/tar.h tar/write_header.c
-sqfs2tar_LDADD = libsquashfs.a libfstree.a libcompress.a libutil.a
+sqfs2tar_SOURCES = tar/sqfs2tar.c
+sqfs2tar_LDADD = libsquashfs.a libtar.a libfstree.a libcompress.a libutil.a
 sqfs2tar_LDADD += $(XZ_LIBS) $(ZLIB_LIBS) $(LZO_LIBS) $(LZ4_LIBS) $(ZSTD_LIBS)
 
-tar2sqfs_SOURCES = tar/tar2sqfs.c tar/skip.c tar/read_header.c tar/tar.h
-tar2sqfs_LDADD = libsquashfs.a libfstree.a libcompress.a libutil.a
+tar2sqfs_SOURCES = tar/tar2sqfs.c
+tar2sqfs_LDADD = libsquashfs.a libtar.a libfstree.a libcompress.a libutil.a
 tar2sqfs_LDADD += $(XZ_LIBS) $(ZLIB_LIBS) $(LZO_LIBS) $(LZ4_LIBS) $(ZSTD_LIBS)
 
 bin_PROGRAMS += sqfs2tar tar2sqfs
diff --git a/tar/read_header.c b/tar/read_header.c
deleted file mode 100644
index bdb2d20..0000000
--- a/tar/read_header.c
+++ /dev/null
@@ -1,415 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-#include "util.h"
-#include "tar.h"
-
-#include <sys/sysmacros.h>
-#include <string.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <stdio.h>
-
-enum {
-	PAX_SIZE = 0x001,
-	PAX_UID = 0x002,
-	PAX_GID = 0x004,
-	PAX_DEV_MAJ = 0x008,
-	PAX_DEV_MIN = 0x010,
-	PAX_NAME = 0x020,
-	PAX_SLINK_TARGET = 0x040,
-	PAX_ATIME = 0x080,
-	PAX_MTIME = 0x100,
-	PAX_CTIME = 0x200,
-};
-
-static int read_octal(const char *str, int digits, uint64_t *out)
-{
-	uint64_t result = 0;
-
-	while (digits > 0 && *str >= '0' && *str <= '7') {
-		if (result > 0x1FFFFFFFFFFFFFFFUL) {
-			fputs("numeric overflow parsing tar header\n", stderr);
-			return -1;
-		}
-
-		result = (result << 3) | (*(str++) - '0');
-		--digits;
-	}
-
-	*out = result;
-	return 0;
-}
-
-static int read_binary(const char *str, int digits, uint64_t *out)
-{
-	uint64_t x, result = 0;
-
-	while (digits > 0) {
-		if (result > 0x00FFFFFFFFFFFFFFUL) {
-			fputs("numeric overflow parsing tar header\n", stderr);
-			return -1;
-		}
-
-		x = *((const unsigned char *)str++);
-		result = (result << 8) | x;
-		--digits;
-	}
-
-	*out = result;
-	return 0;
-}
-
-static int read_number(const char *str, int digits, uint64_t *out)
-{
-	if (*((unsigned char *)str) & 0x80) {
-		if (read_binary(str, digits, out))
-			return -1;
-		*out &= 0x7FFFFFFFFFFFFFFF;
-		return 0;
-	}
-
-	return read_octal(str, digits, out);
-}
-
-static bool is_zero_block(const tar_header_t *hdr)
-{
-	const unsigned char *ptr = (const unsigned char *)hdr;
-
-	return ptr[0] == '\0' && memcmp(ptr, ptr + 1, sizeof(*hdr) - 1) == 0;
-}
-
-static bool is_checksum_valid(const tar_header_t *hdr)
-{
-	unsigned int chksum = 0;
-	tar_header_t copy;
-	uint64_t ref;
-	size_t i;
-
-	if (read_octal(hdr->chksum, sizeof(hdr->chksum), &ref))
-		return false;
-
-	memcpy(&copy, hdr, sizeof(*hdr));
-	memset(copy.chksum, ' ', sizeof(copy.chksum));
-
-	for (i = 0; i < sizeof(copy); ++i)
-		chksum += ((unsigned char *)&copy)[i];
-
-	return chksum == ref;
-}
-
-static bool is_magic_valid(const tar_header_t *hdr)
-{
-	if (memcmp(hdr->magic, TAR_MAGIC, sizeof(hdr->magic)) != 0)
-		return false;
-
-	if (memcmp(hdr->version, TAR_VERSION, sizeof(hdr->version)) != 0)
-		return false;
-
-	return true;
-}
-
-static int pax_read_decimal(const char *str, uint64_t *out)
-{
-	uint64_t result = 0;
-
-	while (*str >= '0' && *str <= '9') {
-		if (result > 0xFFFFFFFFFFFFFFFFUL / 10) {
-			fputs("numeric overflow parsing pax header\n", stderr);
-			return -1;
-		}
-
-		result = (result * 10) + (*(str++) - '0');
-	}
-
-	*out = result;
-	return 0;
-}
-
-static int read_pax_header(int fd, uint64_t entsize, unsigned int *set_by_pax,
-			   tar_header_decoded_t *out)
-{
-	char *buffer, *line;
-	uint64_t field;
-	ssize_t ret;
-	uint64_t i;
-
-	buffer = malloc(entsize + 1);
-	if (buffer == NULL)
-		goto fail_errno;
-
-	ret = read_retry(fd, buffer, entsize);
-	if (ret < 0)
-		goto fail_errno;
-	if ((size_t)ret < entsize)
-		goto fail_eof;
-
-	if (skip_padding(fd, entsize))
-		goto fail;
-
-	buffer[entsize] = '\0';
-
-	for (i = 0; i < entsize; ++i) {
-		while (i < entsize && isspace(buffer[i]))
-			++i;
-		while (i < entsize && isdigit(buffer[i]))
-			++i;
-		while (i < entsize && isspace(buffer[i]))
-			++i;
-		if (i >= entsize)
-			break;
-
-		line = buffer + i;
-
-		while (i < entsize && buffer[i] != '\n')
-			++i;
-
-		buffer[i] = '\0';
-
-		if (!strncmp(line, "uid=", 4)) {
-			pax_read_decimal(line + 4, &field);
-			out->sb.st_uid = field;
-			*set_by_pax |= PAX_UID;
-		} else if (!strncmp(line, "gid=", 4)) {
-			pax_read_decimal(line + 4, &field);
-			out->sb.st_gid = field;
-			*set_by_pax |= PAX_GID;
-		} else if (!strncmp(line, "path=", 5)) {
-			free(out->name);
-			out->name = strdup(line + 5);
-			if (out->name == NULL)
-				goto fail_errno;
-			*set_by_pax |= PAX_NAME;
-		} else if (!strncmp(line, "size=", 5)) {
-			pax_read_decimal(line + 5, &field);
-			out->sb.st_size = field;
-			*set_by_pax |= PAX_SIZE;
-		} else if (!strncmp(line, "linkpath=", 9)) {
-			free(out->link_target);
-			out->link_target = strdup(line + 9);
-			if (out->link_target == NULL)
-				goto fail_errno;
-			*set_by_pax |= PAX_SLINK_TARGET;
-		} else if (!strncmp(line, "atime=", 6)) {
-			pax_read_decimal(line + 6, &field);
-			out->sb.st_atime = field;
-			*set_by_pax |= PAX_ATIME;
-		} else if (!strncmp(line, "mtime=", 6)) {
-			pax_read_decimal(line + 6, &field);
-			out->sb.st_mtime = field;
-			*set_by_pax |= PAX_MTIME;
-		} else if (!strncmp(line, "ctime=", 6)) {
-			pax_read_decimal(line + 6, &field);
-			out->sb.st_ctime = field;
-			*set_by_pax |= PAX_CTIME;
-		}
-	}
-
-	free(buffer);
-	return 0;
-fail_errno:
-	perror("reading pax header");
-	goto fail;
-fail_eof:
-	fputs("reading pax header: unexpected end of file\n", stderr);
-	goto fail;
-fail:
-	free(buffer);
-	return -1;
-}
-
-static int decode_header(const tar_header_t *hdr, unsigned int set_by_pax,
-			 tar_header_decoded_t *out)
-{
-	uint64_t field;
-	size_t count;
-
-	if (!(set_by_pax & PAX_NAME)) {
-		if (hdr->prefix[0] == '\0') {
-			count = strlen(hdr->name) + 1;
-			count += strlen(hdr->prefix) + 1;
-
-			out->name = malloc(count);
-
-			if (out->name != NULL) {
-				sprintf(out->name, "%s/%s",
-					hdr->prefix, hdr->name);
-			}
-		} else {
-			out->name = strdup(hdr->name);
-		}
-
-		if (out->name == NULL) {
-			perror("decoding filename");
-			return -1;
-		}
-	}
-
-	if (!(set_by_pax & PAX_SIZE)) {
-		if (read_number(hdr->size, sizeof(hdr->size), &field))
-			return -1;
-		out->sb.st_size = field;
-	}
-
-	if (!(set_by_pax & PAX_UID)) {
-		if (read_number(hdr->uid, sizeof(hdr->uid), &field))
-			return -1;
-		out->sb.st_uid = field;
-	}
-
-	if (!(set_by_pax & PAX_GID)) {
-		if (read_number(hdr->gid, sizeof(hdr->gid), &field))
-			return -1;
-		out->sb.st_gid = field;
-	}
-
-	if (!(set_by_pax & PAX_DEV_MAJ)) {
-		if (read_number(hdr->devmajor, sizeof(hdr->devmajor), &field))
-			return -1;
-
-		out->sb.st_rdev = makedev(field, minor(out->sb.st_rdev));
-	}
-
-	if (!(set_by_pax & PAX_DEV_MIN)) {
-		if (read_number(hdr->devminor, sizeof(hdr->devminor), &field))
-			return -1;
-
-		out->sb.st_rdev = makedev(major(out->sb.st_rdev), field);
-	}
-
-	if (!(set_by_pax & PAX_MTIME)) {
-		if (read_number(hdr->mtime, sizeof(hdr->mtime), &field))
-			return -1;
-		out->sb.st_mtime = field;
-	}
-
-	if (!(set_by_pax & PAX_ATIME))
-		out->sb.st_atime = out->sb.st_mtime;
-
-	if (!(set_by_pax & PAX_CTIME))
-		out->sb.st_ctime = out->sb.st_mtime;
-
-	if (read_octal(hdr->mode, sizeof(hdr->mode), &field))
-		return -1;
-
-	out->sb.st_mode = field & 07777;
-
-	if (hdr->typeflag == TAR_TYPE_LINK ||
-	    hdr->typeflag == TAR_TYPE_SLINK) {
-		if (!(set_by_pax & PAX_SLINK_TARGET)) {
-			out->link_target = strdup(hdr->linkname);
-			if (out->link_target == NULL) {
-				perror("decoding symlink target");
-				return -1;
-			}
-		}
-	}
-
-	out->unknown_record = false;
-
-	switch (hdr->typeflag) {
-	case '\0':
-	case TAR_TYPE_FILE:
-		out->sb.st_mode |= S_IFREG;
-		break;
-	case TAR_TYPE_LINK:
-		/* XXX: hard links are not support yet */
-		out->sb.st_mode = S_IFLNK | 0777;
-		break;
-	case TAR_TYPE_SLINK:
-		out->sb.st_mode = S_IFLNK | 0777;
-		break;
-	case TAR_TYPE_CHARDEV:
-		out->sb.st_mode |= S_IFCHR;
-		break;
-	case TAR_TYPE_BLOCKDEV:
-		out->sb.st_mode |= S_IFBLK;
-		break;
-	case TAR_TYPE_DIR:
-		out->sb.st_mode |= S_IFDIR;
-		break;
-	case TAR_TYPE_FIFO:
-		out->sb.st_mode |= S_IFIFO;
-		break;
-	default:
-		out->unknown_record = true;
-		break;
-	}
-
-	return 0;
-}
-
-int read_header(int fd, tar_header_decoded_t *out)
-{
-	unsigned int set_by_pax = 0;
-	bool prev_was_zero = false;
-	uint64_t pax_size;
-	tar_header_t hdr;
-	int ret;
-
-	memset(out, 0, sizeof(*out));
-
-	for (;;) {
-		ret = read_retry(fd, &hdr, sizeof(hdr));
-		if (ret == 0)
-			goto out_eof;
-		if (ret < 0)
-			goto fail_errno;
-		if (ret < (int)sizeof(hdr))
-			goto fail_eof;
-
-		if (is_zero_block(&hdr)) {
-			if (prev_was_zero)
-				goto out_eof;
-			prev_was_zero = true;
-			continue;
-		}
-
-		prev_was_zero = false;
-
-		if (!is_magic_valid(&hdr))
-			goto fail_magic;
-
-		if (!is_checksum_valid(&hdr))
-			goto fail_chksum;
-
-		if (hdr.typeflag == TAR_TYPE_PAX) {
-			clear_header(out);
-			if (read_number(hdr.size, sizeof(hdr.size), &pax_size))
-				return -1;
-			set_by_pax = 0;
-			if (read_pax_header(fd, pax_size, &set_by_pax, out))
-				return -1;
-			continue;
-		}
-		break;
-	}
-
-	if (decode_header(&hdr, set_by_pax, out))
-		goto fail;
-
-	return 0;
-out_eof:
-	clear_header(out);
-	return 1;
-fail_errno:
-	perror("reading tar header");
-	goto fail;
-fail_eof:
-	fputs("reading tar header: unexpected end of file\n", stderr);
-	goto fail;
-fail_magic:
-	fputs("input is not a ustar tar archive!\n", stderr);
-	goto fail;
-fail_chksum:
-	fputs("invalid tar header checksum!\n", stderr);
-	goto fail;
-fail:
-	clear_header(out);
-	return -1;
-}
-
-void clear_header(tar_header_decoded_t *hdr)
-{
-	free(hdr->name);
-	free(hdr->link_target);
-	memset(hdr, 0, sizeof(*hdr));
-}
diff --git a/tar/skip.c b/tar/skip.c
deleted file mode 100644
index 69208b2..0000000
--- a/tar/skip.c
+++ /dev/null
@@ -1,48 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-#include "util.h"
-#include "tar.h"
-
-#include <stdio.h>
-
-static int skip_bytes(int fd, uint64_t size)
-{
-	unsigned char buffer[1024];
-	ssize_t ret;
-	size_t diff;
-
-	while (size != 0) {
-		diff = sizeof(buffer);
-		if (diff > size)
-			diff = size;
-
-		ret = read_retry(fd, buffer, diff);
-
-		if (ret < 0) {
-			perror("reading tar record data");
-			return -1;
-		}
-
-		if ((size_t)ret < diff) {
-			fputs("unexpected end of file\n", stderr);
-			return -1;
-		}
-
-		size -= diff;
-	}
-
-	return 0;
-}
-
-int skip_padding(int fd, uint64_t size)
-{
-	size_t tail = size % 512;
-
-	return tail ? skip_bytes(fd, 512 - tail) : 0;
-}
-
-int skip_entry(int fd, uint64_t size)
-{
-	size_t tail = size % 512;
-
-	return skip_bytes(fd, tail ? (size + 512 - tail) : size);
-}
diff --git a/tar/tar.h b/tar/tar.h
deleted file mode 100644
index 7862235..0000000
--- a/tar/tar.h
+++ /dev/null
@@ -1,65 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-#ifndef TAR_H
-#define TAR_H
-
-#include <sys/stat.h>
-#include <stdbool.h>
-
-typedef struct {
-	char name[100];
-	char mode[8];
-	char uid[8];
-	char gid[8];
-	char size[12];
-	char mtime[12];
-	char chksum[8];
-	char typeflag;
-	char linkname[100];
-	char magic[6];
-	char version[2];
-	char uname[32];
-	char gname[32];
-	char devmajor[8];
-	char devminor[8];
-	char prefix[155];
-	char padding[12];
-} tar_header_t;
-
-typedef struct {
-	struct stat sb;
-	char *name;
-	char *link_target;
-	bool unknown_record;
-} tar_header_decoded_t;
-
-#define TAR_TYPE_FILE '0'
-#define TAR_TYPE_LINK '1'
-#define TAR_TYPE_SLINK '2'
-#define TAR_TYPE_CHARDEV '3'
-#define TAR_TYPE_BLOCKDEV '4'
-#define TAR_TYPE_DIR '5'
-#define TAR_TYPE_FIFO '6'
-
-#define TAR_TYPE_PAX 'x'
-
-#define TAR_MAGIC "ustar"
-#define TAR_VERSION "00"
-
-/*
-  Returns < 0 on failure, > 0 if cannot encode, 0 on success.
-  Prints error/warning messages to stderr.
-*/
-int write_tar_header(int fd, const struct stat *sb, const char *name,
-		     const char *slink_target);
-
-/* calcuate and skip the zero padding */
-int skip_padding(int fd, uint64_t size);
-
-/* round up to block size and skip the entire entry */
-int skip_entry(int fd, uint64_t size);
-
-int read_header(int fd, tar_header_decoded_t *out);
-
-void clear_header(tar_header_decoded_t *hdr);
-
-#endif /* TAR_H */
diff --git a/tar/write_header.c b/tar/write_header.c
deleted file mode 100644
index 80db327..0000000
--- a/tar/write_header.c
+++ /dev/null
@@ -1,248 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-#include "util.h"
-#include "tar.h"
-
-#include <sys/sysmacros.h>
-#include <string.h>
-#include <stdio.h>
-
-static unsigned long pax_hdr_counter = 0;
-static char buffer[4096];
-
-static void write_octal(char *dst, unsigned int value, int digits)
-{
-	char temp[64];
-
-	sprintf(temp, "%0*o ", digits, value);
-	memcpy(dst, temp, strlen(temp));
-}
-
-static int name_to_tar_header(tar_header_t *hdr, const char *path)
-{
-	size_t len = strlen(path);
-	const char *ptr;
-
-	if ((len + 1) <= sizeof(hdr->name)) {
-		memcpy(hdr->name, path, len);
-		return 0;
-	}
-
-	for (ptr = path; ; ++ptr) {
-		ptr = strchr(ptr, '/');
-		if (ptr == NULL)
-			return -1;
-
-		len = ptr - path;
-		if (len >= sizeof(hdr->prefix))
-			continue;
-		if (strlen(ptr + 1) >= sizeof(hdr->name))
-			continue;
-		break;
-	}
-
-	memcpy(hdr->prefix, path, ptr - path);
-	memcpy(hdr->name, ptr + 1, strlen(ptr + 1));
-	return 0;
-}
-
-static void init_header(tar_header_t *hdr, const struct stat *sb,
-			const char *name, const char *slink_target)
-{
-	memset(hdr, 0, sizeof(*hdr));
-
-	name_to_tar_header(hdr, name);
-	memcpy(hdr->magic, TAR_MAGIC, sizeof(hdr->magic));
-	memcpy(hdr->version, TAR_VERSION, sizeof(hdr->version));
-	write_octal(hdr->mode, sb->st_mode & ~S_IFMT, 6);
-	write_octal(hdr->uid, sb->st_uid, 6);
-	write_octal(hdr->gid, sb->st_gid, 6);
-	write_octal(hdr->mtime, sb->st_mtime, 11);
-	write_octal(hdr->size, 0, 11);
-	write_octal(hdr->devmajor, 0, 6);
-	write_octal(hdr->devminor, 0, 6);
-
-	switch (sb->st_mode & S_IFMT) {
-	case S_IFREG:
-		write_octal(hdr->size, sb->st_size & 077777777777L, 11);
-		break;
-	case S_IFLNK:
-		if (sb->st_size < (off_t)sizeof(hdr->linkname))
-			strcpy(hdr->linkname, slink_target);
-		break;
-	case S_IFCHR:
-	case S_IFBLK:
-		write_octal(hdr->devmajor, major(sb->st_rdev), 6);
-		write_octal(hdr->devminor, minor(sb->st_rdev), 6);
-		break;
-	}
-
-	sprintf(hdr->uname, "%u", sb->st_uid);
-	sprintf(hdr->gname, "%u", sb->st_gid);
-}
-
-static void update_checksum(tar_header_t *hdr)
-{
-	unsigned int chksum = 0;
-	size_t i;
-
-	memset(hdr->chksum, ' ', sizeof(hdr->chksum));
-
-	for (i = 0; i < sizeof(*hdr); ++i)
-		chksum += ((unsigned char *)hdr)[i];
-
-	write_octal(hdr->chksum, chksum, 6);
-	hdr->chksum[6] = '\0';
-	hdr->chksum[7] = ' ';
-}
-
-static bool need_pax_header(const struct stat *sb, const char *name)
-{
-	tar_header_t tmp;
-
-	if (sb->st_uid > 0777777 || sb->st_gid > 0777777)
-		return true;
-
-	if (S_ISREG(sb->st_mode) && sb->st_size > 077777777777L)
-		return true;
-
-	if (S_ISLNK(sb->st_mode) && sb->st_size >= (off_t)sizeof(tmp.linkname))
-		return true;
-
-	if (name_to_tar_header(&tmp, name))
-		return true;
-
-	return false;
-}
-
-static char *write_pax_entry(char *dst, const char *key, const char *value)
-{
-	size_t i, len, prefix = 0, oldprefix;
-
-	do {
-		len = prefix + 1 + strlen(key) + 1 + strlen(value) + 1;
-
-		oldprefix = prefix;
-		prefix = 1;
-
-		for (i = len; i >= 10; i /= 10)
-			++prefix;
-	} while (oldprefix != prefix);
-
-	sprintf(dst, "%zu %s=%s\n", len, key, value);
-
-	return dst + len;
-}
-
-static int write_pax_header(int fd, const struct stat *sb, const char *name,
-			    const char *slink_target)
-{
-	char temp[64], *ptr;
-	struct stat fakesb;
-	tar_header_t hdr;
-	ssize_t ret;
-	size_t len;
-
-	memset(buffer, 0, sizeof(buffer));
-	memset(&fakesb, 0, sizeof(fakesb));
-	fakesb.st_mode = S_IFREG | 0644;
-
-	sprintf(temp, "pax%lu", pax_hdr_counter);
-	init_header(&hdr, &fakesb, temp, NULL);
-	hdr.typeflag = TAR_TYPE_PAX;
-
-	sprintf(temp, "%u", sb->st_uid);
-	ptr = buffer;
-	ptr = write_pax_entry(ptr, "uid", temp);
-	ptr = write_pax_entry(ptr, "uname", temp);
-
-	sprintf(temp, "%lu", sb->st_mtime);
-	ptr = write_pax_entry(ptr, "mtime", temp);
-
-	sprintf(temp, "%u", sb->st_gid);
-	ptr = write_pax_entry(ptr, "gid", temp);
-	ptr = write_pax_entry(ptr, "gname", temp);
-
-	ptr = write_pax_entry(ptr, "path", name);
-
-	if (S_ISLNK(sb->st_mode)) {
-		ptr = write_pax_entry(ptr, "linkpath", slink_target);
-	} else if (S_ISREG(sb->st_mode)) {
-		sprintf(temp, "%lu", sb->st_size);
-		ptr = write_pax_entry(ptr, "size", temp);
-	}
-
-	len = strlen(buffer);
-	write_octal(hdr.size, len, 11);
-	update_checksum(&hdr);
-
-	ret = write_retry(fd, &hdr, sizeof(hdr));
-	if (ret < 0)
-		goto fail_wr;
-	if ((size_t)ret < sizeof(hdr))
-		goto fail_trunc;
-
-	ret = write_retry(fd, buffer, len);
-	if (ret < 0)
-		goto fail_wr;
-	if ((size_t)ret < len)
-		goto fail_trunc;
-
-	return padd_file(fd, len, 512);
-fail_wr:
-	perror("writing pax header");
-	return -1;
-fail_trunc:
-	fputs("writing pax header: truncated write\n", stderr);
-	return -1;
-}
-
-int write_tar_header(int fd, const struct stat *sb, const char *name,
-		     const char *slink_target)
-{
-	const char *reason;
-	tar_header_t hdr;
-	ssize_t ret;
-
-	if (need_pax_header(sb, name)) {
-		if (write_pax_header(fd, sb, name, slink_target))
-			return -1;
-
-		sprintf(buffer, "pax%lu_data", pax_hdr_counter++);
-		name = buffer;
-	}
-
-	init_header(&hdr, sb, name, slink_target);
-
-	switch (sb->st_mode & S_IFMT) {
-	case S_IFCHR: hdr.typeflag = TAR_TYPE_CHARDEV; break;
-	case S_IFBLK: hdr.typeflag = TAR_TYPE_BLOCKDEV; break;
-	case S_IFLNK: hdr.typeflag = TAR_TYPE_SLINK; break;
-	case S_IFREG: hdr.typeflag = TAR_TYPE_FILE; break;
-	case S_IFDIR: hdr.typeflag = TAR_TYPE_DIR; break;
-	case S_IFIFO: hdr.typeflag = TAR_TYPE_FIFO; break;
-	case S_IFSOCK:
-		reason = "cannot pack socket";
-		goto out_skip;
-	default:
-		reason = "unknown type";
-		goto out_skip;
-	}
-
-	update_checksum(&hdr);
-
-	ret = write_retry(fd, &hdr, sizeof(hdr));
-
-	if (ret < 0) {
-		perror("writing header record");
-	} else if ((size_t)ret < sizeof(hdr)) {
-		fputs("writing header record: truncated write\n", stderr);
-		ret = -1;
-	} else {
-		ret = 0;
-	}
-
-	return ret;
-out_skip:
-	fprintf(stderr, "WARNING: skipping '%s' (%s)\n", name, reason);
-	return 1;
-}