gensquashfs: add option to simply pack an input directory

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

6 files changed, 283 insertions, 47 deletions

diff --git a/include/fstree.h b/include/fstree.h
index 6a29093..13d4c78 100644
--- a/include/fstree.h
+++ b/include/fstree.h
@@ -229,6 +229,13 @@ void fstree_xattr_deduplicate(fstree_t *fs);
  */
 int fstree_from_file(fstree_t *fs, const char *filename);
 
+/*
+  Recursively scan a directory and generate a file system tree from it.
+
+  Returns 0 on success, prints errors to stderr.
+ */
+int fstree_from_dir(fstree_t *fs, const char *path);
+
 /* Lexicographically sort all directory contents. */
 void fstree_sort(fstree_t *fs);
 
diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index efb6b77..447acfb 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -1,5 +1,5 @@
 libfstree_a_SOURCES = lib/fstree/fstree.c lib/fstree/fstree_from_file.c
-libfstree_a_SOURCES += lib/fstree/fstree_sort.c
+libfstree_a_SOURCES += lib/fstree/fstree_sort.c lib/fstree/fstree_from_dir.c
 libfstree_a_SOURCES += include/fstree.h
 libfstree_a_CFLAGS = $(AM_CFLAGS)
 libfstree_a_CPPFLAGS = $(AM_CPPFLAGS)
diff --git a/lib/fstree/fstree_from_dir.c b/lib/fstree/fstree_from_dir.c
new file mode 100644
index 0000000..fb906f1
--- /dev/null
+++ b/lib/fstree/fstree_from_dir.c
@@ -0,0 +1,189 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "fstree.h"
+#include "util.h"
+
+#include <sys/types.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <fcntl.h>
+
+static size_t path_size(tree_node_t *n)
+{
+	size_t size = 0;
+
+	while (n != NULL) {
+		size += strlen(n->name) + 1;
+		n = n->parent;
+	}
+
+	return size;
+}
+
+static char *print_path(char *ptr, tree_node_t *n)
+{
+	if (n->parent != NULL) {
+		ptr = print_path(ptr, n->parent);
+		*(ptr++) = '/';
+		strcpy(ptr, n->name);
+		return ptr + strlen(ptr);
+	}
+
+	return ptr;
+}
+
+static int populate_dir(tree_node_t *root, int fd, size_t blocksize,
+			const char *rootdir)
+{
+	size_t size, blockcount;
+	struct dirent *ent;
+	struct stat sb;
+	tree_node_t *n;
+	ssize_t ret;
+	void *ptr;
+	DIR *dir;
+	int cfd;
+
+	dir = fdopendir(fd);
+	if (dir == NULL) {
+		perror("fdopendir");
+		close(fd);
+		return -1;
+	}
+
+	for (;;) {
+		n = NULL;
+		errno = 0;
+		ent = readdir(dir);
+
+		if (ent == NULL) {
+			if (errno) {
+				perror("readdir");
+				goto fail;
+			}
+			break;
+		}
+
+		if (!strcmp(ent->d_name, "..") || !strcmp(ent->d_name, "."))
+			continue;
+
+		if (fstatat(fd, ent->d_name, &sb, AT_SYMLINK_NOFOLLOW)) {
+			perror(ent->d_name);
+			goto fail;
+		}
+
+		size = sizeof(tree_node_t) + strlen(ent->d_name) + 1;
+
+		switch (sb.st_mode & S_IFMT) {
+		case S_IFLNK:
+			size += sb.st_size + 1;
+			break;
+		case S_IFREG:
+			blockcount = sb.st_size / blocksize + 1;
+
+			size += sizeof(file_info_t);
+			size += sizeof(uint32_t) * blockcount;
+
+			size += path_size(root) + strlen(ent->d_name) + 1;
+			size += strlen(rootdir) + 2;
+			break;
+		case S_IFDIR:
+			size += sizeof(dir_info_t);
+			break;
+		}
+
+		n = calloc(1, size);
+		if (n == NULL) {
+			perror("allocating tree node");
+			goto fail;
+		}
+
+		n->uid = sb.st_uid;
+		n->gid = sb.st_gid;
+		n->mode = sb.st_mode;
+		n->parent = root;
+
+		ptr = n->payload;
+
+		switch (sb.st_mode & S_IFMT) {
+		case S_IFLNK:
+			ret = readlinkat(fd, ent->d_name, ptr, sb.st_size);
+			if (ret < 0) {
+				perror("readlink");
+				goto fail;
+			}
+
+			n->data.slink_target = ptr;
+			ptr = (char *)ptr + strlen(ptr) + 1;
+			break;
+		case S_IFBLK:
+		case S_IFCHR:
+			n->data.devno = sb.st_rdev;
+			break;
+		case S_IFDIR:
+			n->data.dir = ptr;
+			ptr = (char *)ptr + sizeof(dir_info_t);
+			break;
+		case S_IFREG:
+			n->data.file = ptr;
+			ptr = (char *)ptr + sizeof(file_info_t);
+			ptr = (char *)ptr + sizeof(uint32_t) * blockcount;
+
+			n->data.file->input_file = ptr;
+			n->data.file->size = sb.st_size;
+
+			strcpy(ptr, rootdir);
+			ptr = (char *)ptr + strlen(ptr);
+			ptr = print_path(ptr, root);
+
+			*((char*)ptr) = '/';
+			strcpy((char *)ptr + 1, ent->d_name);
+			ptr = (char *)ptr + strlen(ptr) + 1;
+			break;
+		}
+
+		n->name = ptr;
+		strcpy(ptr, ent->d_name);
+
+		n->next = root->data.dir->children;
+		root->data.dir->children = n;
+	}
+
+	for (n = root->data.dir->children; n != NULL; n = n->next) {
+		if (S_ISDIR(n->mode)) {
+			cfd = openat(fd, n->name, O_RDONLY | O_DIRECTORY);
+			if (cfd < 0) {
+				perror(n->name);
+				goto fail_dir;
+			}
+
+			if (populate_dir(n, cfd, blocksize, rootdir)) {
+				close(cfd);
+				goto fail_dir;
+			}
+		}
+	}
+
+	closedir(dir);
+	return 0;
+fail:
+	free(n);
+fail_dir:
+	closedir(dir);
+	return -1;
+}
+
+int fstree_from_dir(fstree_t *fs, const char *path)
+{
+	int fd = open(path, O_RDONLY | O_DIRECTORY);
+
+	if (fd < 0) {
+		perror(path);
+		return -1;
+	}
+
+	return populate_dir(fs->root, fd, fs->block_size, path);
+}
diff --git a/mkfs/mkfs.c b/mkfs/mkfs.c
index 1fd95be..63b9c98 100644
--- a/mkfs/mkfs.c
+++ b/mkfs/mkfs.c
@@ -70,8 +70,18 @@ int main(int argc, char **argv)
 		goto out_outfd;
 	}
 
-	if (fstree_from_file(&info.fs, info.opt.infile))
-		goto out_fstree;
+	switch (info.opt.mode) {
+	case PACK_FILE:
+		if (fstree_from_file(&info.fs, info.opt.infile))
+			goto out_fstree;
+		break;
+	case PACK_DIR:
+		if (fstree_from_dir(&info.fs, info.opt.infile))
+			goto out_fstree;
+		break;
+	default:
+		assert(0);
+	}
 
 #ifdef WITH_SELINUX
 	if (info.opt.selinux != NULL) {
diff --git a/mkfs/mkfs.h b/mkfs/mkfs.h
index ca998ac..67dc994 100644
--- a/mkfs/mkfs.h
+++ b/mkfs/mkfs.h
@@ -9,6 +9,7 @@
 #include "config.h"
 #include "table.h"
 
+#include <assert.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
@@ -16,6 +17,12 @@
 #include <fcntl.h>
 #include <errno.h>
 
+typedef enum {
+	PACK_NONE,
+	PACK_FILE,
+	PACK_DIR,
+} E_PACK_MODE;
+
 typedef struct {
 	unsigned int def_uid;
 	unsigned int def_gid;
@@ -30,6 +37,7 @@ typedef struct {
 	const char *outfile;
 	const char *selinux;
 	char *comp_extra;
+	E_PACK_MODE mode;
 } options_t;
 
 typedef struct {
diff --git a/mkfs/options.c b/mkfs/options.c
index 36539b7..56bc7d6 100644
--- a/mkfs/options.c
+++ b/mkfs/options.c
@@ -17,6 +17,8 @@ static struct option long_opts[] = {
 	{ "dev-block-size", required_argument, NULL, 'B' },
 	{ "defaults", required_argument, NULL, 'd' },
 	{ "comp-extra", required_argument, NULL, 'X' },
+	{ "pack-file", required_argument, NULL, 'F' },
+	{ "pack-dir", required_argument, NULL, 'D' },
 	{ "force", no_argument, NULL, 'f' },
 	{ "quiet", no_argument, NULL, 'q' },
 #ifdef WITH_SELINUX
@@ -27,9 +29,9 @@ static struct option long_opts[] = {
 };
 
 #ifdef WITH_SELINUX
-static const char *short_opts = "s:X:c:b:B:d:fqhV";
+static const char *short_opts = "s:F:D:X:c:b:B:d:fqhV";
 #else
-static const char *short_opts = "X:c:b:B:d:fqhV";
+static const char *short_opts = "F:D:X:c:b:B:d:fqhV";
 #endif
 
 enum {
@@ -50,48 +52,18 @@ static const char *defaults[] = {
 extern char *__progname;
 
 static const char *help_string =
-"Usage: %s [OPTIONS] <file-list> <squashfs-file>\n"
-"\n"
-"<file-list> is a file containing newline separated entries that describe\n"
-"the files to be included in the squashfs image:\n"
-"\n"
-"# a comment\n"
-"file <path> <mode> <uid> <gid> [<location>]\n"
-"dir <path> <mode> <uid> <gid>\n"
-"nod <path> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
-"slink <path> <mode> <uid> <gid> <target>\n"
-"pipe <path> <mode> <uid> <gid>\n"
-"sock <path> <mode> <uid> <gid>\n"
-"\n"
-"<path>       Absolute path of the entry in the image.\n"
-"<location>   If given, location of the input file. Either absolute or relative\n"
-"             to the description file. If omitted, the image path is used,\n"
-"             relative to the description file.\n"
-"<target>     Symlink target.\n"
-"<mode>       Mode/permissions of the entry.\n"
-"<uid>        Numeric user id.\n"
-"<gid>        Numeric group id.\n"
-"<dev_type>   Device type (b=block, c=character).\n"
-"<maj>        Major number of a device special file.\n"
-"<min>        Minor number of a device special file.\n"
-"\n"
-"Example:\n"
-"# A simple squashfs image\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"
-"\n"
-"# Add a file. Input is relative to this listing.\n"
-"file /sbin/init 0755 0 0 ../init/sbin/init\n"
-"\n"
-"# Read from ./bin/bash. /bin is created implicitly with default attributes.\n"
-"file /bin/bash 0755 0 0"
+"Usage: %s [OPTIONS...] <squashfs-file>\n"
 "\n"
 "Possible options:\n"
 "\n"
+"  --pack-file, -F <file>      Use a `gen_init_cpio` style description file.\n"
+"                              The file format is specified below.\n"
+"  --pack-dir, -D <directory>  Pack the contents of the given directory into\n"
+"                              a SquashFS image. The directory becomes the\n"
+"                              root of the file system.\n"
 "  --compressor, -c <name>     Select the compressor to use.\n"
-"                              directories (defaults to 'xz').\n"
+"                              A list of available compressors is below.\n"
+"                              Defaults to 'xz'.\n"
 "  --comp-extra, -X <options>  A comma seperated list of extra options for\n"
 "                              the selected compressor. Specify 'help' to\n"
 "                              get a list of available options.\n"
@@ -116,7 +88,44 @@ static const char *help_string =
 "  --quiet, -q                 Do not print out progress reports.\n"
 "  --help, -h                  Print help text and exit.\n"
 "  --version, -V               Print version information and exit.\n"
-"\n";
+"\n"
+"When using the pack file option, the given file is expected to contain\n"
+"newline separated entries that describe the files to be included in the\n"
+"SquashFS image. The following entry types can be specified:\n"
+"\n"
+"# a comment\n"
+"file <path> <mode> <uid> <gid> [<location>]\n"
+"dir <path> <mode> <uid> <gid>\n"
+"nod <path> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
+"slink <path> <mode> <uid> <gid> <target>\n"
+"pipe <path> <mode> <uid> <gid>\n"
+"sock <path> <mode> <uid> <gid>\n"
+"\n"
+"<path>       Absolute path of the entry in the image.\n"
+"<location>   If given, location of the input file. Either absolute or relative\n"
+"             to the description file. If omitted, the image path is used,\n"
+"             relative to the description file.\n"
+"<target>     Symlink target.\n"
+"<mode>       Mode/permissions of the entry.\n"
+"<uid>        Numeric user id.\n"
+"<gid>        Numeric group id.\n"
+"<dev_type>   Device type (b=block, c=character).\n"
+"<maj>        Major number of a device special file.\n"
+"<min>        Minor number of a device special file.\n"
+"\n"
+"Example:\n"
+"    # A simple squashfs image\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"
+"    \n"
+"    # Add a file. Input is relative to this listing.\n"
+"    file /sbin/init 0755 0 0 ../init/sbin/init\n"
+"    \n"
+"    # Read from bin/bash relative to the listing. Implicitly create /bin.\n"
+"    file /bin/bash 0755 0 0"
+"\n\n";
 
 static const char *compressors[] = {
 	[SQFS_COMP_GZIP] = "gzip",
@@ -237,6 +246,7 @@ void process_command_line(options_t *opt, int argc, char **argv)
 	opt->devblksz = SQFS_DEVBLK_SIZE;
 	opt->infile = NULL;
 	opt->outfile = NULL;
+	opt->mode = PACK_NONE;
 
 	for (;;) {
 		i = getopt_long(argc, argv, short_opts, long_opts, NULL);
@@ -283,6 +293,14 @@ void process_command_line(options_t *opt, int argc, char **argv)
 		case 'X':
 			opt->comp_extra = optarg;
 			break;
+		case 'F':
+			opt->mode = PACK_FILE;
+			opt->infile = optarg;
+			break;
+		case 'D':
+			opt->mode = PACK_DIR;
+			opt->infile = optarg;
+			break;
 #ifdef WITH_SELINUX
 		case 's':
 			opt->selinux = optarg;
@@ -313,12 +331,16 @@ void process_command_line(options_t *opt, int argc, char **argv)
 		exit(EXIT_SUCCESS);
 	}
 
-	if ((optind + 1) >= argc) {
-		fputs("Missing arguments: input and output files.\n", stderr);
+	if (opt->mode == PACK_NONE) {
+		fputs("No input file or directory specified.\n", stderr);
+		goto fail_arg;
+	}
+
+	if (optind >= argc) {
+		fputs("No output file specified.\n", stderr);
 		goto fail_arg;
 	}
 
-	opt->infile = argv[optind++];
 	opt->outfile = argv[optind++];
 	return;
 fail_arg: