Add libfsimage, a C library for reading files from filesystem images.

Initial support is provided for Solaris UFS, ext2 (both using libext2fs
and not), and reiserfs.

Signed-off-by: John Levon <john.levon@sun.com>

2 files changed, 186 insertions, 0 deletions

diff --git a/tools/libfsimage/ext2fs-lib/Makefile b/tools/libfsimage/ext2fs-lib/Makefile
new file mode 100644
index 0000000000..a60b3a58a5
--- /dev/null
+++ b/tools/libfsimage/ext2fs-lib/Makefile
@@ -0,0 +1,15 @@
+XEN_ROOT = ../../..
+
+LIB_SRCS-y = ext2fs-lib.c
+
+FS = ext2fs-lib
+
+FS_LIBDEPS = -lext2fs
+
+.PHONY: all
+all: fs-all
+
+.PHONY: install
+install: fs-install
+
+include $(XEN_ROOT)/tools/libfsimage/Rules.mk
diff --git a/tools/libfsimage/ext2fs-lib/ext2fs-lib.c b/tools/libfsimage/ext2fs-lib/ext2fs-lib.c
new file mode 100644
index 0000000000..ef7cec521c
--- /dev/null
+++ b/tools/libfsimage/ext2fs-lib/ext2fs-lib.c
@@ -0,0 +1,171 @@
+/*
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#include <fsimage_plugin.h>
+#include <ext2fs/ext2fs.h>
+#include <errno.h>
+
+static int
+ext2lib_mount(fsi_t *fsi, const char *name)
+{
+	int err;
+	char opts[30] = "";
+	ext2_filsys *fs;
+	uint64_t offset = fsip_fs_offset(fsi);
+
+	if (offset)
+		snprintf(opts, 29, "offset=%lld", offset);
+
+	fs = malloc(sizeof (*fs));
+	if (fs == NULL)
+		return (-1);
+
+	err = ext2fs_open2(name, opts, 0, 0, 0, unix_io_manager, fs);
+
+	if (err != 0) {
+		free(fs);
+		errno = EINVAL;
+		return (-1);
+	}
+
+	fsip_fs_set_data(fsi, fs);
+	return (0);
+}
+
+static int
+ext2lib_umount(fsi_t *fsi)
+{
+	ext2_filsys *fs = fsip_fs_data(fsi);
+	if (ext2fs_close(*fs) != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+	return (0);
+}
+
+fsi_file_t *
+ext2lib_open(fsi_t *fsi, const char *path)
+{
+	ext2_ino_t ino;
+	ext2_filsys *fs = fsip_fs_data(fsi);
+	ext2_file_t *f;
+	fsi_file_t *file;
+	int err;
+
+	err = ext2fs_namei_follow(*fs, EXT2_ROOT_INO, EXT2_ROOT_INO,
+	    path, &ino);
+
+	if (err != 0) {
+		errno = ENOENT;
+		return (NULL);
+	}
+
+	f = malloc(sizeof (*f));
+	if (f == NULL)
+		return (NULL);
+
+	err = ext2fs_file_open(*fs, ino, 0, f);
+
+	if (err != 0) {
+		free(f);
+		errno = EINVAL;
+		return (NULL);
+	}
+
+	file = fsip_file_alloc(fsi, f);
+	if (file == NULL)
+		free(f);
+	return (file);
+}
+
+ssize_t
+ext2lib_read(fsi_file_t *file, void *buf, size_t nbytes)
+{
+	ext2_file_t *f = fsip_file_data(file);
+	unsigned int n;
+	int err;
+
+	err = ext2fs_file_read(*f, buf, nbytes, &n);
+	if (err != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	return (n);
+}
+
+ssize_t
+ext2lib_pread(fsi_file_t *file, void *buf, size_t nbytes, uint64_t off)
+{
+	ext2_file_t *f = fsip_file_data(file);
+	uint64_t tmpoff;
+	unsigned int n;
+	int err;
+
+	if ((err = ext2fs_file_llseek(*f, 0, EXT2_SEEK_CUR, &tmpoff)) != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	if ((err = ext2fs_file_llseek(*f, off, EXT2_SEEK_SET, NULL)) != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	err = ext2fs_file_read(*f, buf, nbytes, &n);
+
+	ext2fs_file_llseek(*f, tmpoff, EXT2_SEEK_SET, NULL);
+
+	if (err != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	return (n);
+}
+
+int
+ext2lib_close(fsi_file_t *file)
+{
+	ext2_file_t *f = fsip_file_data(file);
+	ext2fs_file_close(*f);
+	free(f);
+	return (0);
+}
+
+fsi_plugin_ops_t *
+fsi_init_plugin(int version, fsi_plugin_t *fp, const char **name)
+{
+	static fsi_plugin_ops_t ops = {
+		FSIMAGE_PLUGIN_VERSION,
+		.fpo_mount = ext2lib_mount,
+		.fpo_umount = ext2lib_umount,
+		.fpo_open = ext2lib_open,
+		.fpo_read = ext2lib_read,
+		.fpo_pread = ext2lib_pread,
+		.fpo_close = ext2lib_close
+	};
+
+	*name = "ext2fs-lib";
+	return (&ops);
+}