[Libguestfs] [PATCH febootstrap 4/8] Refactor cpio code into separate file.
Richard W.M. Jones
rjones at redhat.com
Fri Aug 20 10:40:11 UTC 2010
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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>From a241e323e209b0da30396408574c8e3d89b323e0 Mon Sep 17 00:00:00 2001
From: Richard Jones <rjones at redhat.com>
Date: Thu, 19 Aug 2010 14:23:11 +0100
Subject: [PATCH 4/8] Refactor cpio code into separate file.
We create a 'writer' abstraction and (currently) a single implementation
of this which can write cpio files. All cpio-related code is moved
out of 'appliance.c' into 'cpio.c'. 'appliance.c' becomes a generic
appliance builder.
This commit should not change the semantics of the program.
---
helper/Makefile.am | 1 +
helper/appliance.c | 274 +++++----------------------------------------------
helper/cpio.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++++++
helper/helper.h | 26 +++++-
helper/main.c | 3 +-
5 files changed, 333 insertions(+), 249 deletions(-)
create mode 100644 helper/cpio.c
diff --git a/helper/Makefile.am b/helper/Makefile.am
index fb21286..985d4b2 100644
--- a/helper/Makefile.am
+++ b/helper/Makefile.am
@@ -24,6 +24,7 @@ DISTCLEANFILES = $(bin_SCRIPTS)
febootstrap_supermin_helper_SOURCES = \
helper.h \
appliance.c \
+ cpio.c \
kernel.c \
main.c \
utils.c
diff --git a/helper/appliance.c b/helper/appliance.c
index c6defc0..b7a46c0 100644
--- a/helper/appliance.c
+++ b/helper/appliance.c
@@ -22,7 +22,6 @@
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-#include <limits.h>
#include <fcntl.h>
#include <errno.h>
#include <dirent.h>
@@ -32,32 +31,15 @@
#include "error.h"
#include "fts_.h"
-#include "full-write.h"
#include "xalloc.h"
#include "xvasprintf.h"
#include "helper.h"
-/* Buffer size used in copy operations throughout. Large for
- * greatest efficiency.
- */
-#define BUFFER_SIZE 65536
-
-static void iterate_inputs (char **inputs, int nr_inputs);
-static void iterate_input_directory (const char *dirname, int dirfd);
-static void write_kernel_modules (const char *whitelist, const char *modpath);
-static void write_hostfiles (const char *hostfiles_file);
-static void write_to_fd (const void *buffer, size_t len);
-static void write_file_to_fd (const char *filename);
-static void write_file_len_to_fd (const char *filename, size_t len);
-static void write_padding (size_t len);
-static void cpio_append_fts_entry (FTSENT *entry);
-static void cpio_append_stat (const char *filename, struct stat *);
-static void cpio_append (const char *filename);
-static void cpio_append_trailer (void);
-
-static int out_fd = -1;
-static off_t out_offset = 0;
+static void iterate_inputs (char **inputs, int nr_inputs, struct writer *);
+static void iterate_input_directory (const char *dirname, int dirfd, struct writer *);
+static void add_kernel_modules (const char *whitelist, const char *modpath, struct writer *);
+static void add_hostfiles (const char *hostfiles_file, struct writer *);
/* Create the appliance.
*
@@ -86,30 +68,24 @@ void
create_appliance (char **inputs, int nr_inputs,
const char *whitelist,
const char *modpath,
- const char *appliance)
+ const char *appliance,
+ struct writer *writer)
{
- out_fd = open (appliance, O_WRONLY | O_CREAT | O_TRUNC | O_NOCTTY, 0644);
- if (out_fd == -1)
- error (EXIT_FAILURE, errno, "open: %s", appliance);
- out_offset = 0;
+ writer->wr_start (appliance);
- iterate_inputs (inputs, nr_inputs);
+ iterate_inputs (inputs, nr_inputs, writer);
/* Kernel modules (3). */
- write_kernel_modules (whitelist, modpath);
-
- cpio_append_trailer ();
+ add_kernel_modules (whitelist, modpath, writer);
- /* Finish off and close output file. */
- if (close (out_fd) == -1)
- error (EXIT_FAILURE, errno, "close: %s", appliance);
+ writer->wr_end ();
}
/* Iterate over the inputs to find out what they are, visiting
* directories if specified.
*/
static void
-iterate_inputs (char **inputs, int nr_inputs)
+iterate_inputs (char **inputs, int nr_inputs, struct writer *writer)
{
int i;
for (i = 0; i < nr_inputs; ++i) {
@@ -126,16 +102,16 @@ iterate_inputs (char **inputs, int nr_inputs)
/* Directory? */
if (S_ISDIR (statbuf.st_mode))
- iterate_input_directory (inputs[i], fd);
+ iterate_input_directory (inputs[i], fd, writer);
else if (S_ISREG (statbuf.st_mode)) {
/* Is it a cpio file? */
char buf[6];
if (read (fd, buf, 6) == 6 && memcmp (buf, "070701", 6) == 0)
/* Yes, a cpio file. This is a skeleton appliance, case (1). */
- write_file_to_fd (inputs[i]);
+ writer->wr_cpio_file (inputs[i]);
else
/* No, must be hostfiles, case (2). */
- write_hostfiles (inputs[i]);
+ add_hostfiles (inputs[i], writer);
}
else
error (EXIT_FAILURE, 0, "%s: input is not a regular file or directory",
@@ -146,7 +122,7 @@ iterate_inputs (char **inputs, int nr_inputs)
}
static void
-iterate_input_directory (const char *dirname, int dirfd)
+iterate_input_directory (const char *dirname, int dirfd, struct writer *writer)
{
char path[PATH_MAX];
strcpy (path, dirname);
@@ -165,7 +141,7 @@ iterate_input_directory (const char *dirname, int dirfd)
continue;
strcpy (&path[len], d->d_name);
- iterate_inputs (inputs, 1);
+ iterate_inputs (inputs, 1, writer);
}
if (errno != 0)
@@ -188,7 +164,8 @@ iterate_input_directory (const char *dirname, int dirfd)
* whitelist_file may be NULL, to include ALL kernel modules.
*/
static void
-write_kernel_modules (const char *whitelist_file, const char *modpath)
+add_kernel_modules (const char *whitelist_file, const char *modpath,
+ struct writer *writer)
{
char **whitelist = NULL;
if (whitelist_file != NULL)
@@ -197,13 +174,13 @@ write_kernel_modules (const char *whitelist_file, const char *modpath)
char *paths[2] = { (char *) modpath, NULL };
FTS *fts = fts_open (paths, FTS_COMFOLLOW|FTS_PHYSICAL, NULL);
if (fts == NULL)
- error (EXIT_FAILURE, errno, "write_kernel_modules: fts_open: %s", modpath);
+ error (EXIT_FAILURE, errno, "add_kernel_modules: fts_open: %s", modpath);
for (;;) {
errno = 0;
FTSENT *entry = fts_read (fts);
if (entry == NULL && errno != 0)
- error (EXIT_FAILURE, errno, "write_kernel_modules: fts_read: %s", modpath);
+ error (EXIT_FAILURE, errno, "add_kernel_modules: fts_read: %s", modpath);
if (entry == NULL)
break;
@@ -227,7 +204,7 @@ write_kernel_modules (const char *whitelist_file, const char *modpath)
if (verbose >= 2)
fprintf (stderr, "including kernel module %s (matches whitelist entry %s)\n",
entry->fts_name, whitelist[j]);
- cpio_append_fts_entry (entry);
+ writer->wr_fts_entry (entry);
break;
} else if (r != FNM_NOMATCH)
error (EXIT_FAILURE, 0, "internal error: fnmatch ('%s', '%s', %d) returned unexpected non-zero value %d\n",
@@ -236,15 +213,15 @@ write_kernel_modules (const char *whitelist_file, const char *modpath)
} else { /* whitelist == NULL, always include */
if (verbose >= 2)
fprintf (stderr, "including kernel module %s\n", entry->fts_name);
- cpio_append_fts_entry (entry);
+ writer->wr_fts_entry (entry);
}
} else
/* It's some other sort of file, or a directory, always include. */
- cpio_append_fts_entry (entry);
+ writer->wr_fts_entry (entry);
}
if (fts_close (fts) == -1)
- error (EXIT_FAILURE, errno, "write_kernel_modules: fts_close: %s", modpath);
+ error (EXIT_FAILURE, errno, "add_kernel_modules: fts_close: %s", modpath);
}
/* Copy the host files.
@@ -254,7 +231,7 @@ write_kernel_modules (const char *whitelist_file, const char *modpath)
* that exist. Ignore any files that don't exist or are not readable.
*/
static void
-write_hostfiles (const char *hostfiles_file)
+add_hostfiles (const char *hostfiles_file, struct writer *writer)
{
char **hostfiles = load_file (hostfiles_file);
@@ -287,7 +264,7 @@ write_hostfiles (const char *hostfiles_file)
if (verbose >= 2)
fprintf (stderr, "including host file %s (matches %s)\n", tmp, patt);
- cpio_append (tmp);
+ writer->wr_file (tmp);
free (tmp);
}
@@ -298,204 +275,7 @@ write_hostfiles (const char *hostfiles_file)
fprintf (stderr, "including host file %s (directly referenced)\n",
hostfile);
- cpio_append_stat (hostfile, &statbuf);
+ writer->wr_file_stat (hostfile, &statbuf);
} /* Ignore files that don't exist. */
}
}
-
-/* Copy contents of buffer to out_fd and keep out_offset correct. */
-static void
-write_to_fd (const void *buffer, size_t len)
-{
- if (full_write (out_fd, buffer, len) != len)
- error (EXIT_FAILURE, errno, "write");
- out_offset += len;
-}
-
-/* Copy contents of file to out_fd. */
-static void
-write_file_to_fd (const char *filename)
-{
- char buffer[BUFFER_SIZE];
- int fd2;
- ssize_t r;
-
- if (verbose >= 2)
- fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd);
-
- fd2 = open (filename, O_RDONLY);
- if (fd2 == -1)
- error (EXIT_FAILURE, errno, "open: %s", filename);
- for (;;) {
- r = read (fd2, buffer, sizeof buffer);
- if (r == 0)
- break;
- if (r == -1) {
- if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
- continue;
- error (EXIT_FAILURE, errno, "read: %s", filename);
- }
- write_to_fd (buffer, r);
- }
-
- if (close (fd2) == -1)
- error (EXIT_FAILURE, errno, "close: %s", filename);
-}
-
-/* Copy file of given length to output, and fail if the file has
- * changed size.
- */
-static void
-write_file_len_to_fd (const char *filename, size_t len)
-{
- char buffer[BUFFER_SIZE];
- size_t count = 0;
-
- if (verbose >= 2)
- fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd);
-
- int fd2 = open (filename, O_RDONLY);
- if (fd2 == -1)
- error (EXIT_FAILURE, errno, "open: %s", filename);
- for (;;) {
- ssize_t r = read (fd2, buffer, sizeof buffer);
- if (r == 0)
- break;
- if (r == -1) {
- if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
- continue;
- error (EXIT_FAILURE, errno, "read: %s", filename);
- }
- write_to_fd (buffer, r);
- count += r;
- if (count > len)
- error (EXIT_FAILURE, 0, "write_file_len_to_fd: %s: file has increased in size\n", filename);
- }
-
- if (close (fd2) == -1)
- error (EXIT_FAILURE, errno, "close: %s", filename);
-
- if (count != len)
- error (EXIT_FAILURE, 0, "febootstrap-supermin-helper: write_file_len_to_fd: %s: file has changed size\n", filename);
-}
-
-/* Append the file pointed to by FTSENT to the cpio output. */
-static void
-cpio_append_fts_entry (FTSENT *entry)
-{
- if (entry->fts_info & FTS_NS || entry->fts_info & FTS_NSOK)
- cpio_append (entry->fts_path);
- else
- cpio_append_stat (entry->fts_path, entry->fts_statp);
-}
-
-/* Append the file named 'filename' to the cpio output. */
-static void
-cpio_append (const char *filename)
-{
- struct stat statbuf;
-
- if (lstat (filename, &statbuf) == -1)
- error (EXIT_FAILURE, errno, "lstat: %s", filename);
- cpio_append_stat (filename, &statbuf);
-}
-
-/* Append the file to the cpio output. */
-#define PADDING(len) ((((len) + 3) & ~3) - (len))
-
-#define CPIO_HEADER_LEN (6 + 13*8)
-
-static void
-cpio_append_stat (const char *filename, struct stat *statbuf)
-{
- const char *orig_filename = filename;
-
- if (*filename == '/')
- filename++;
- if (*filename == '\0')
- filename = ".";
-
- if (verbose >= 2)
- fprintf (stderr, "cpio_append_stat %s 0%o -> %d\n",
- orig_filename, statbuf->st_mode, out_fd);
-
- /* Regular files and symlinks are the only ones that have a "body"
- * in this cpio entry.
- */
- int has_body = S_ISREG (statbuf->st_mode) || S_ISLNK (statbuf->st_mode);
-
- size_t len = strlen (filename) + 1;
-
- char header[CPIO_HEADER_LEN + 1];
- snprintf (header, sizeof header,
- "070701" /* magic */
- "%08X" /* inode */
- "%08X" /* mode */
- "%08X" "%08X" /* uid, gid */
- "%08X" /* nlink */
- "%08X" /* mtime */
- "%08X" /* file length */
- "%08X" "%08X" /* device holding file major, minor */
- "%08X" "%08X" /* for specials, device major, minor */
- "%08X" /* name length (including \0 byte) */
- "%08X", /* checksum (not used by the kernel) */
- (unsigned) statbuf->st_ino, statbuf->st_mode,
- statbuf->st_uid, statbuf->st_gid,
- (unsigned) statbuf->st_nlink, (unsigned) statbuf->st_mtime,
- has_body ? (unsigned) statbuf->st_size : 0,
- major (statbuf->st_dev), minor (statbuf->st_dev),
- major (statbuf->st_rdev), minor (statbuf->st_rdev),
- (unsigned) len, 0);
-
- /* Write the header. */
- write_to_fd (header, CPIO_HEADER_LEN);
-
- /* Follow with the filename, and pad it. */
- write_to_fd (filename, len);
- size_t padding_len = PADDING (CPIO_HEADER_LEN + len);
- write_padding (padding_len);
-
- /* Follow with the file or symlink content, and pad it. */
- if (has_body) {
- if (S_ISREG (statbuf->st_mode))
- write_file_len_to_fd (orig_filename, statbuf->st_size);
- else if (S_ISLNK (statbuf->st_mode)) {
- char tmp[PATH_MAX];
- if (readlink (orig_filename, tmp, sizeof tmp) == -1)
- error (EXIT_FAILURE, errno, "readlink: %s", orig_filename);
- write_to_fd (tmp, statbuf->st_size);
- }
-
- padding_len = PADDING (statbuf->st_size);
- write_padding (padding_len);
- }
-}
-
-/* CPIO voodoo. */
-static void
-cpio_append_trailer (void)
-{
- struct stat statbuf;
- memset (&statbuf, 0, sizeof statbuf);
- statbuf.st_nlink = 1;
- cpio_append_stat ("TRAILER!!!", &statbuf);
-
- /* CPIO seems to pad up to the next block boundary, ie. up to
- * the next 512 bytes.
- */
- write_padding (((out_offset + 511) & ~511) - out_offset);
- assert ((out_offset & 511) == 0);
-}
-
-/* Write 'len' bytes of zeroes out. */
-static void
-write_padding (size_t len)
-{
- static const char buffer[512] = { 0 };
-
- while (len > 0) {
- size_t n = len < sizeof buffer ? len : sizeof buffer;
- write_to_fd (buffer, n);
- len -= n;
- }
-}
diff --git a/helper/cpio.c b/helper/cpio.c
new file mode 100644
index 0000000..f9ffc3f
--- /dev/null
+++ b/helper/cpio.c
@@ -0,0 +1,278 @@
+/* febootstrap-supermin-helper reimplementation in C.
+ * Copyright (C) 2009-2010 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <assert.h>
+
+#include "error.h"
+#include "fts_.h"
+#include "full-write.h"
+#include "xalloc.h"
+#include "xvasprintf.h"
+
+#include "helper.h"
+
+/* Buffer size used in copy operations throughout. Large for
+ * greatest efficiency.
+ */
+#define BUFFER_SIZE 65536
+
+static int out_fd = -1;
+static off_t out_offset = 0;
+
+static void write_file_to_fd (const char *filename);
+static void write_file_len_to_fd (const char *filename, size_t len);
+static void write_padding (size_t len);
+static void cpio_append_fts_entry (FTSENT *entry);
+static void cpio_append_stat (const char *filename, const struct stat *);
+static void cpio_append (const char *filename);
+static void cpio_append_trailer (void);
+
+/* Copy contents of buffer to out_fd and keep out_offset correct. */
+static void
+write_to_fd (const void *buffer, size_t len)
+{
+ if (full_write (out_fd, buffer, len) != len)
+ error (EXIT_FAILURE, errno, "write");
+ out_offset += len;
+}
+
+/* Copy contents of file to out_fd. */
+static void
+write_file_to_fd (const char *filename)
+{
+ char buffer[BUFFER_SIZE];
+ int fd2;
+ ssize_t r;
+
+ if (verbose >= 2)
+ fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd);
+
+ fd2 = open (filename, O_RDONLY);
+ if (fd2 == -1)
+ error (EXIT_FAILURE, errno, "open: %s", filename);
+ for (;;) {
+ r = read (fd2, buffer, sizeof buffer);
+ if (r == 0)
+ break;
+ if (r == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
+ continue;
+ error (EXIT_FAILURE, errno, "read: %s", filename);
+ }
+ write_to_fd (buffer, r);
+ }
+
+ if (close (fd2) == -1)
+ error (EXIT_FAILURE, errno, "close: %s", filename);
+}
+
+/* Copy file of given length to output, and fail if the file has
+ * changed size.
+ */
+static void
+write_file_len_to_fd (const char *filename, size_t len)
+{
+ char buffer[BUFFER_SIZE];
+ size_t count = 0;
+
+ if (verbose >= 2)
+ fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd);
+
+ int fd2 = open (filename, O_RDONLY);
+ if (fd2 == -1)
+ error (EXIT_FAILURE, errno, "open: %s", filename);
+ for (;;) {
+ ssize_t r = read (fd2, buffer, sizeof buffer);
+ if (r == 0)
+ break;
+ if (r == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
+ continue;
+ error (EXIT_FAILURE, errno, "read: %s", filename);
+ }
+ write_to_fd (buffer, r);
+ count += r;
+ if (count > len)
+ error (EXIT_FAILURE, 0, "write_file_len_to_fd: %s: file has increased in size\n", filename);
+ }
+
+ if (close (fd2) == -1)
+ error (EXIT_FAILURE, errno, "close: %s", filename);
+
+ if (count != len)
+ error (EXIT_FAILURE, 0, "febootstrap-supermin-helper: write_file_len_to_fd: %s: file has changed size\n", filename);
+}
+
+/* Append the file pointed to by FTSENT to the cpio output. */
+static void
+cpio_append_fts_entry (FTSENT *entry)
+{
+ if (entry->fts_info & FTS_NS || entry->fts_info & FTS_NSOK)
+ cpio_append (entry->fts_path);
+ else
+ cpio_append_stat (entry->fts_path, entry->fts_statp);
+}
+
+/* Append the file named 'filename' to the cpio output. */
+static void
+cpio_append (const char *filename)
+{
+ struct stat statbuf;
+
+ if (lstat (filename, &statbuf) == -1)
+ error (EXIT_FAILURE, errno, "lstat: %s", filename);
+ cpio_append_stat (filename, &statbuf);
+}
+
+/* Append the file to the cpio output. */
+#define PADDING(len) ((((len) + 3) & ~3) - (len))
+
+#define CPIO_HEADER_LEN (6 + 13*8)
+
+static void
+cpio_append_stat (const char *filename, const struct stat *statbuf)
+{
+ const char *orig_filename = filename;
+
+ if (*filename == '/')
+ filename++;
+ if (*filename == '\0')
+ filename = ".";
+
+ if (verbose >= 2)
+ fprintf (stderr, "cpio_append_stat %s 0%o -> %d\n",
+ orig_filename, statbuf->st_mode, out_fd);
+
+ /* Regular files and symlinks are the only ones that have a "body"
+ * in this cpio entry.
+ */
+ int has_body = S_ISREG (statbuf->st_mode) || S_ISLNK (statbuf->st_mode);
+
+ size_t len = strlen (filename) + 1;
+
+ char header[CPIO_HEADER_LEN + 1];
+ snprintf (header, sizeof header,
+ "070701" /* magic */
+ "%08X" /* inode */
+ "%08X" /* mode */
+ "%08X" "%08X" /* uid, gid */
+ "%08X" /* nlink */
+ "%08X" /* mtime */
+ "%08X" /* file length */
+ "%08X" "%08X" /* device holding file major, minor */
+ "%08X" "%08X" /* for specials, device major, minor */
+ "%08X" /* name length (including \0 byte) */
+ "%08X", /* checksum (not used by the kernel) */
+ (unsigned) statbuf->st_ino, statbuf->st_mode,
+ statbuf->st_uid, statbuf->st_gid,
+ (unsigned) statbuf->st_nlink, (unsigned) statbuf->st_mtime,
+ has_body ? (unsigned) statbuf->st_size : 0,
+ major (statbuf->st_dev), minor (statbuf->st_dev),
+ major (statbuf->st_rdev), minor (statbuf->st_rdev),
+ (unsigned) len, 0);
+
+ /* Write the header. */
+ write_to_fd (header, CPIO_HEADER_LEN);
+
+ /* Follow with the filename, and pad it. */
+ write_to_fd (filename, len);
+ size_t padding_len = PADDING (CPIO_HEADER_LEN + len);
+ write_padding (padding_len);
+
+ /* Follow with the file or symlink content, and pad it. */
+ if (has_body) {
+ if (S_ISREG (statbuf->st_mode))
+ write_file_len_to_fd (orig_filename, statbuf->st_size);
+ else if (S_ISLNK (statbuf->st_mode)) {
+ char tmp[PATH_MAX];
+ if (readlink (orig_filename, tmp, sizeof tmp) == -1)
+ error (EXIT_FAILURE, errno, "readlink: %s", orig_filename);
+ write_to_fd (tmp, statbuf->st_size);
+ }
+
+ padding_len = PADDING (statbuf->st_size);
+ write_padding (padding_len);
+ }
+}
+
+/* CPIO voodoo. */
+static void
+cpio_append_trailer (void)
+{
+ struct stat statbuf;
+ memset (&statbuf, 0, sizeof statbuf);
+ statbuf.st_nlink = 1;
+ cpio_append_stat ("TRAILER!!!", &statbuf);
+
+ /* CPIO seems to pad up to the next block boundary, ie. up to
+ * the next 512 bytes.
+ */
+ write_padding (((out_offset + 511) & ~511) - out_offset);
+ assert ((out_offset & 511) == 0);
+}
+
+/* Write 'len' bytes of zeroes out. */
+static void
+write_padding (size_t len)
+{
+ static const char buffer[512] = { 0 };
+
+ while (len > 0) {
+ size_t n = len < sizeof buffer ? len : sizeof buffer;
+ write_to_fd (buffer, n);
+ len -= n;
+ }
+}
+
+static void
+cpio_start (const char *appliance)
+{
+ out_fd = open (appliance, O_WRONLY | O_CREAT | O_TRUNC | O_NOCTTY, 0644);
+ if (out_fd == -1)
+ error (EXIT_FAILURE, errno, "open: %s", appliance);
+ out_offset = 0;
+}
+
+static void
+cpio_end (void)
+{
+ cpio_append_trailer ();
+
+ /* Finish off and close output file. */
+ if (close (out_fd) == -1)
+ error (EXIT_FAILURE, errno, "close");
+}
+
+struct writer cpio_writer = {
+ .wr_start = cpio_start,
+ .wr_end = cpio_end,
+ .wr_file = cpio_append,
+ .wr_file_stat = cpio_append_stat,
+ .wr_fts_entry = cpio_append_fts_entry,
+ .wr_cpio_file = write_file_to_fd,
+};
diff --git a/helper/helper.h b/helper/helper.h
index e9618ba..75b6eb3 100644
--- a/helper/helper.h
+++ b/helper/helper.h
@@ -19,12 +19,36 @@
#ifndef FEBOOTSTRAP_SUPERMIN_HELPER_H
#define FEBOOTSTRAP_SUPERMIN_HELPER_H
+#include <sys/stat.h>
+#include "fts_.h"
+
+struct writer {
+ /* Start a new appliance, finish one off. */
+ void (*wr_start) (const char *appliance);
+ void (*wr_end) (void);
+
+ /* Append the named host file to the appliance being built. The
+ * wr_file_stat form is used where we have already stat'd this file,
+ * to avoid having to stat it a second time. The wr_fts_entry form
+ * is used where the caller has an FTSENT.
+ */
+ void (*wr_file) (const char *filename);
+ void (*wr_file_stat) (const char *filename, const struct stat *);
+ void (*wr_fts_entry) (FTSENT *entry);
+
+ /* Append the contents of cpio file to the appliance being built. */
+ void (*wr_cpio_file) (const char *cpio_file);
+};
+
/* main.c */
extern struct timeval start_t;
extern int verbose;
/* appliance.c */
-extern void create_appliance (char **inputs, int nr_inputs, const char *whitelist, const char *modpath, const char *appliance);
+extern void create_appliance (char **inputs, int nr_inputs, const char *whitelist, const char *modpath, const char *appliance, struct writer *writer);
+
+/* cpio.c */
+extern struct writer cpio_writer;
/* kernel.c */
extern const char *create_kernel (const char *hostcpu, const char *kernel);
diff --git a/helper/main.c b/helper/main.c
index d350b4e..a448b9e 100644
--- a/helper/main.c
+++ b/helper/main.c
@@ -152,7 +152,8 @@ main (int argc, char *argv[])
print_timestamped_message ("finished creating kernel");
/* Create the appliance. */
- create_appliance (inputs, nr_inputs, whitelist, modpath, appliance);
+ create_appliance (inputs, nr_inputs, whitelist, modpath, appliance,
+ &cpio_writer);
if (verbose)
print_timestamped_message ("finished creating appliance");
--
1.7.1
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