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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
commitcfe5e3905201349e9cf3f95d52ff4bd100bde37d (patch)
treed0baf160cbee3195249d095f85e52d20c21acf02 /disk-utils/mkfs.cramfs.c
parentInitial commit. (diff)
downloadutil-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.tar.xz
util-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.zip
Adding upstream version 2.39.3.upstream/2.39.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'disk-utils/mkfs.cramfs.c')
-rw-r--r--disk-utils/mkfs.cramfs.c943
1 files changed, 943 insertions, 0 deletions
diff --git a/disk-utils/mkfs.cramfs.c b/disk-utils/mkfs.cramfs.c
new file mode 100644
index 0000000..fcc1314
--- /dev/null
+++ b/disk-utils/mkfs.cramfs.c
@@ -0,0 +1,943 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * mkcramfs - make a cramfs file system
+ *
+ * Copyright (C) 1999-2002 Transmeta Corporation
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ * Old version would die on largish filesystems. Change to mmap the
+ * files one by one instead of all simultaneously. - aeb, 2002-11-01
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <getopt.h>
+#include <zconf.h>
+
+/* We don't use our include/crc32.h, but crc32 from zlib!
+ *
+ * The zlib implementation performs pre/post-conditioning. The util-linux
+ * imlemenation requires post-conditioning (xor) in the applications.
+ */
+#include <zlib.h>
+
+#include "blkdev.h"
+#include "c.h"
+#include "cramfs.h"
+#include "md5.h"
+#include "nls.h"
+#include "exitcodes.h"
+#include "strutils.h"
+
+#define CLOSE_EXIT_CODE MKFS_EX_ERROR
+#include "closestream.h"
+
+#define XALLOC_EXIT_CODE MKFS_EX_ERROR
+#include "xalloc.h"
+
+/* The kernel only supports PAD_SIZE of 0 and 512. */
+#define PAD_SIZE 512
+
+static int verbose = 0;
+
+static unsigned int blksize = 0; /* settable via -b option, default page size */
+static long total_blocks = 0, total_nodes = 1; /* pre-count the root node */
+static int image_length = 0;
+static int cramfs_is_big_endian = 0; /* target is big endian */
+
+/*
+ * If opt_holes is set, then mkcramfs can create explicit holes in the
+ * data, which saves 26 bytes per hole (which is a lot smaller a
+ * saving than for most filesystems).
+ *
+ * Note that kernels up to at least 2.3.39 don't support cramfs holes,
+ * which is why this is turned off by default.
+ */
+static unsigned int opt_edition = 0;
+static int opt_errors = 0;
+static int opt_holes = 0;
+static int opt_pad = 0;
+static char *opt_image = NULL;
+static char *opt_name = NULL;
+
+static int warn_dev = 0;
+static int warn_gid = 0;
+static int warn_namelen = 0;
+static int warn_skip = 0;
+static int warn_size = 0;
+static int warn_uid = 0;
+
+/* entry.flags */
+#define CRAMFS_EFLAG_MD5 1
+#define CRAMFS_EFLAG_INVALID 2
+
+/* In-core version of inode / directory entry. */
+struct entry {
+ /* stats */
+ unsigned char *name;
+ unsigned int mode, size, uid, gid;
+ unsigned char md5sum[UL_MD5LENGTH];
+ unsigned char flags; /* CRAMFS_EFLAG_* */
+
+ /* FS data */
+ char *path;
+ int fd; /* temporarily open files while mmapped */
+ struct entry *same; /* points to other identical file */
+ unsigned int offset; /* pointer to compressed data in archive */
+ unsigned int dir_offset; /* offset of directory entry in archive */
+
+ /* organization */
+ struct entry *child; /* NULL for non-directory and empty dir */
+ struct entry *next;
+};
+
+/*
+ * Width of various bitfields in struct cramfs_inode.
+ * Used only to generate warnings.
+ */
+#define CRAMFS_SIZE_WIDTH 24
+#define CRAMFS_UID_WIDTH 16
+#define CRAMFS_GID_WIDTH 8
+#define CRAMFS_OFFSET_WIDTH 26
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ fputs(USAGE_HEADER, stdout);
+ printf(_(" %s [-h] [-v] [-b blksize] [-e edition] [-N endian] [-i file] [-n name] dirname outfile\n"),
+ program_invocation_short_name);
+ fputs(USAGE_SEPARATOR, stdout);
+ puts(_("Make compressed ROM file system."));
+ fputs(USAGE_OPTIONS, stdout);
+ puts(_( " -v be verbose"));
+ puts(_( " -E make all warnings errors (non-zero exit status)"));
+ puts(_( " -b blksize use this blocksize, must equal page size"));
+ puts(_( " -e edition set edition number (part of fsid)"));
+ printf(_(" -N endian set cramfs endianness (%s|%s|%s), default %s\n"), "big", "little", "host", "host");
+ puts(_( " -i file insert a file image into the filesystem"));
+ puts(_( " -n name set name of cramfs filesystem"));
+ printf(_(" -p pad by %d bytes for boot code\n"), PAD_SIZE);
+ puts(_( " -s sort directory entries (old option, ignored)"));
+ puts(_( " -z make explicit holes"));
+ puts(_( " -l[=<mode>] use exclusive device lock (yes, no or nonblock)"));
+ puts(_( " dirname root of the filesystem to be compressed"));
+ puts(_( " outfile output file"));
+ fputs(USAGE_SEPARATOR, stdout);
+ printf(USAGE_HELP_OPTIONS(16));
+ printf(USAGE_MAN_TAIL("mkfs.cramfs(8)"));
+ exit(MKFS_EX_OK);
+}
+
+static char *
+do_mmap(char *path, unsigned int size, unsigned int mode){
+ int fd;
+ char *start = NULL;
+
+ if (!size)
+ return NULL;
+
+ if (S_ISLNK(mode)) {
+ /* The link buffer is unnecessary to terminate by null as it's
+ * always used as buffer rather than a string */
+ start = xmalloc(size);
+ if (readlink(path, start, size) < 0) {
+ warn(_("readlink failed: %s"), path);
+ warn_skip = 1;
+ goto err;
+ }
+ return start;
+ }
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0) {
+ warn(_("cannot open %s"), path);
+ warn_skip = 1;
+ goto err;
+ }
+
+ start = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+ if (start == MAP_FAILED)
+ err(MKFS_EX_ERROR, "mmap");
+ return start;
+err:
+ free(start);
+ return NULL;
+}
+
+static void
+do_munmap(char *start, unsigned int size, unsigned int mode){
+ if (S_ISLNK(mode))
+ free(start);
+ else
+ munmap(start, size);
+}
+
+/* compute md5sums, so that we do not have to compare every pair of files */
+static void
+mdfile(struct entry *e) {
+ char *start;
+
+ start = do_mmap(e->path, e->size, e->mode);
+ if (start == NULL) {
+ e->flags |= CRAMFS_EFLAG_INVALID;
+ } else {
+ UL_MD5_CTX ctx;
+
+ ul_MD5Init(&ctx);
+ ul_MD5Update(&ctx, (unsigned char *) start, e->size);
+ ul_MD5Final(e->md5sum, &ctx);
+
+ do_munmap(start, e->size, e->mode);
+
+ e->flags |= CRAMFS_EFLAG_MD5;
+ }
+}
+
+/* md5 digests are equal; files are almost certainly the same,
+ but just to be sure, do the comparison */
+static int
+identical_file(struct entry *e1, struct entry *e2){
+ char *start1, *start2;
+ int equal;
+
+ start1 = do_mmap(e1->path, e1->size, e1->mode);
+ if (!start1)
+ return 0;
+ start2 = do_mmap(e2->path, e2->size, e2->mode);
+ if (!start2) {
+ do_munmap(start1, e1->size, e1->mode);
+ return 0;
+ }
+ equal = !memcmp(start1, start2, e1->size);
+ do_munmap(start1, e1->size, e1->mode);
+ do_munmap(start2, e2->size, e2->mode);
+ return equal;
+}
+
+/*
+ * The longest file name component to allow for in the input directory tree.
+ * Ext2fs (and many others) allow up to 255 bytes. A couple of filesystems
+ * allow longer (e.g. smbfs 1024), but there isn't much use in supporting
+ * >255-byte names in the input directory tree given that such names get
+ * truncated to 255 bytes when written to cramfs.
+ */
+#define MAX_INPUT_NAMELEN 255
+
+static int find_identical_file(struct entry *orig, struct entry *new, loff_t *fslen_ub)
+{
+ if (orig == new)
+ return 1;
+ if (!orig)
+ return 0;
+ if (orig->size == new->size && orig->path) {
+ if (!orig->flags)
+ mdfile(orig);
+ if (!new->flags)
+ mdfile(new);
+
+ if ((orig->flags & CRAMFS_EFLAG_MD5) &&
+ (new->flags & CRAMFS_EFLAG_MD5) &&
+ !memcmp(orig->md5sum, new->md5sum, UL_MD5LENGTH) &&
+ identical_file(orig, new)) {
+ new->same = orig;
+ *fslen_ub -= new->size;
+ return 1;
+ }
+ }
+ return find_identical_file(orig->child, new, fslen_ub) ||
+ find_identical_file(orig->next, new, fslen_ub);
+}
+
+static void eliminate_doubles(struct entry *root, struct entry *orig, loff_t *fslen_ub) {
+ if (orig) {
+ if (orig->size && orig->path)
+ find_identical_file(root,orig, fslen_ub);
+ eliminate_doubles(root,orig->child, fslen_ub);
+ eliminate_doubles(root,orig->next, fslen_ub);
+ }
+}
+
+/*
+ * We define our own sorting function instead of using alphasort which
+ * uses strcoll and changes ordering based on locale information.
+ */
+static int cramsort (const struct dirent **a, const struct dirent **b)
+{
+ return strcmp((*a)->d_name, (*b)->d_name);
+}
+
+static unsigned int parse_directory(struct entry *root_entry, const char *name, struct entry **prev, loff_t *fslen_ub)
+{
+ struct dirent **dirlist;
+ int totalsize = 0, dircount, dirindex;
+ char *path, *endpath;
+ size_t len = strlen(name);
+
+ /* Set up the path. */
+ /* TODO: Reuse the parent's buffer to save memcpy'ing and duplication. */
+ path = xmalloc(len + 1 + MAX_INPUT_NAMELEN + 1);
+ memcpy(path, name, len);
+ endpath = path + len;
+ *endpath = '/';
+ endpath++;
+
+ /* read in the directory and sort */
+ dircount = scandir(name, &dirlist, NULL, cramsort);
+
+ if (dircount < 0)
+ err(MKFS_EX_ERROR, _("could not read directory %s"), name);
+
+ /* process directory */
+ for (dirindex = 0; dirindex < dircount; dirindex++) {
+ struct dirent *dirent;
+ struct entry *entry;
+ struct stat st;
+ int size;
+ size_t namelen;
+
+ dirent = dirlist[dirindex];
+
+ /* Ignore "." and ".." - we won't be adding them
+ to the archive */
+ if (dirent->d_name[0] == '.') {
+ if (dirent->d_name[1] == '\0')
+ continue;
+ if (dirent->d_name[1] == '.' &&
+ dirent->d_name[2] == '\0')
+ continue;
+ }
+ namelen = strlen(dirent->d_name);
+ if (namelen > MAX_INPUT_NAMELEN) {
+ namelen = MAX_INPUT_NAMELEN;
+ warn_namelen = 1;
+ }
+
+ memcpy(endpath, dirent->d_name, namelen + 1);
+
+ if (lstat(path, &st) < 0) {
+ warn(_("stat of %s failed"), endpath);
+ warn_skip = 1;
+ continue;
+ }
+ entry = xcalloc(1, sizeof(struct entry));
+ entry->name = (unsigned char *)xstrndup(dirent->d_name, namelen);
+ entry->mode = st.st_mode;
+ entry->size = st.st_size;
+ entry->uid = st.st_uid;
+ if (entry->uid >= 1 << CRAMFS_UID_WIDTH)
+ warn_uid = 1;
+ entry->gid = st.st_gid;
+ if (entry->gid >= 1 << CRAMFS_GID_WIDTH)
+ /* TODO: We ought to replace with a default
+ gid instead of truncating; otherwise there
+ are security problems. Maybe mode should
+ be &= ~070. Same goes for uid once Linux
+ supports >16-bit uids. */
+ warn_gid = 1;
+ size = sizeof(struct cramfs_inode) + ((namelen + 3) & ~3);
+ *fslen_ub += size;
+ if (S_ISDIR(st.st_mode)) {
+ entry->size = parse_directory(root_entry, path, &entry->child, fslen_ub);
+ } else if (S_ISREG(st.st_mode)) {
+ entry->path = xstrdup(path);
+ if (entry->size >= (1 << CRAMFS_SIZE_WIDTH)) {
+ warn_size = 1;
+ entry->size = (1 << CRAMFS_SIZE_WIDTH) - 1;
+ }
+ } else if (S_ISLNK(st.st_mode)) {
+ entry->path = xstrdup(path);
+ } else if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode)) {
+ /* maybe we should skip sockets */
+ entry->size = 0;
+ } else {
+ entry->size = st.st_rdev;
+ if (entry->size & -(1<<CRAMFS_SIZE_WIDTH))
+ warn_dev = 1;
+ }
+
+ if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
+ int blocks = ((entry->size - 1) / blksize + 1);
+
+ /* block pointers & data expansion allowance + data */
+ if (entry->size)
+ *fslen_ub += (4+26)*blocks + entry->size + 3;
+ }
+
+ /* Link it into the list */
+ *prev = entry;
+ prev = &entry->next;
+ totalsize += size;
+ }
+ free(path);
+ free(dirlist); /* allocated by scandir() with malloc() */
+ return totalsize;
+}
+
+/* Returns sizeof(struct cramfs_super), which includes the root inode. */
+static unsigned int write_superblock(struct entry *root, char *base, int size)
+{
+ struct cramfs_super *super = (struct cramfs_super *) base;
+ unsigned int offset = sizeof(struct cramfs_super) + image_length;
+
+ if (opt_pad) {
+ offset += opt_pad;
+ }
+
+ super->magic = CRAMFS_MAGIC;
+ super->flags = CRAMFS_FLAG_FSID_VERSION_2 | CRAMFS_FLAG_SORTED_DIRS;
+ if (opt_holes)
+ super->flags |= CRAMFS_FLAG_HOLES;
+ if (image_length > 0)
+ super->flags |= CRAMFS_FLAG_SHIFTED_ROOT_OFFSET;
+ super->size = size;
+ memcpy(super->signature, CRAMFS_SIGNATURE, sizeof(super->signature));
+
+ super->fsid.crc = crc32(0L, NULL, 0);
+ super->fsid.edition = opt_edition;
+ super->fsid.blocks = total_blocks;
+ super->fsid.files = total_nodes;
+
+ memset(super->name, 0x00, sizeof(super->name));
+ if (opt_name)
+ str2memcpy((char *)super->name, opt_name, sizeof(super->name));
+ else
+ str2memcpy((char *)super->name, "Compressed", sizeof(super->name));
+
+ super->root.mode = root->mode;
+ super->root.uid = root->uid;
+ super->root.gid = root->gid;
+ super->root.size = root->size;
+ super->root.offset = offset >> 2;
+
+ super_toggle_endianness(cramfs_is_big_endian, super);
+ inode_from_host(cramfs_is_big_endian, &super->root, &super->root);
+
+ return offset;
+}
+
+static void set_data_offset(struct entry *entry, char *base, unsigned long offset)
+{
+ struct cramfs_inode *inode = (struct cramfs_inode *) (base + entry->dir_offset);
+ inode_to_host(cramfs_is_big_endian, inode, inode);
+ if (offset >= (1 << (2 + CRAMFS_OFFSET_WIDTH)))
+ errx(MKFS_EX_ERROR, _("filesystem too big. Exiting."));
+ inode->offset = (offset >> 2);
+ inode_from_host(cramfs_is_big_endian, inode, inode);
+}
+
+
+/*
+ * We do a width-first printout of the directory
+ * entries, using a stack to remember the directories
+ * we've seen.
+ */
+static unsigned int write_directory_structure(struct entry *entry, char *base, unsigned int offset)
+{
+ int stack_entries = 0;
+ int stack_size = 64;
+ struct entry **entry_stack;
+
+ entry_stack = xmalloc(stack_size * sizeof(struct entry *));
+
+ for (;;) {
+ int dir_start = stack_entries;
+ while (entry) {
+ struct cramfs_inode *inode =
+ (struct cramfs_inode *) (base + offset);
+ size_t len = strlen((const char *)entry->name);
+
+ entry->dir_offset = offset;
+
+ inode->mode = entry->mode;
+ inode->uid = entry->uid;
+ inode->gid = entry->gid;
+ inode->size = entry->size;
+ inode->offset = 0;
+ /* Non-empty directories, regfiles and symlinks will
+ write over inode->offset later. */
+
+ offset += sizeof(struct cramfs_inode);
+ total_nodes++; /* another node */
+ memcpy(base + offset, entry->name, len);
+ /* Pad up the name to a 4-byte boundary */
+ while (len & 3) {
+ *(base + offset + len) = '\0';
+ len++;
+ }
+ inode->namelen = len >> 2;
+ offset += len;
+
+ if (verbose)
+ printf(" %s\n", entry->name);
+ if (entry->child) {
+ if (stack_entries >= stack_size) {
+ stack_size *= 2;
+ entry_stack = xrealloc(entry_stack, stack_size * sizeof(struct entry *));
+ }
+ entry_stack[stack_entries] = entry;
+ stack_entries++;
+ }
+ inode_from_host(cramfs_is_big_endian, inode, inode);
+ entry = entry->next;
+ }
+
+ /*
+ * Reverse the order the stack entries pushed during
+ * this directory, for a small optimization of disk
+ * access in the created fs. This change makes things
+ * `ls -UR' order.
+ */
+ {
+ struct entry **lo = entry_stack + dir_start;
+ struct entry **hi = entry_stack + stack_entries;
+ struct entry *tmp;
+
+ while (lo < --hi) {
+ tmp = *lo;
+ *lo++ = *hi;
+ *hi = tmp;
+ }
+ }
+
+ /* Pop a subdirectory entry from the stack, and recurse. */
+ if (!stack_entries)
+ break;
+ stack_entries--;
+ entry = entry_stack[stack_entries];
+
+ set_data_offset(entry, base, offset);
+ if (verbose)
+ printf("'%s':\n", entry->name);
+ entry = entry->child;
+ }
+ free(entry_stack);
+ return offset;
+}
+
+static int is_zero(unsigned char const *begin, unsigned len)
+{
+ if (opt_holes)
+ /* Returns non-zero iff the first LEN bytes from BEGIN are
+ all NULs. */
+ return (len-- == 0 ||
+ (begin[0] == '\0' &&
+ (len-- == 0 ||
+ (begin[1] == '\0' &&
+ (len-- == 0 ||
+ (begin[2] == '\0' &&
+ (len-- == 0 ||
+ (begin[3] == '\0' &&
+ memcmp(begin, begin + 4, len) == 0))))))));
+
+ /* Never create holes. */
+ return 0;
+}
+
+/*
+ * One 4-byte pointer per block and then the actual blocked
+ * output. The first block does not need an offset pointer,
+ * as it will start immediately after the pointer block;
+ * so the i'th pointer points to the end of the i'th block
+ * (i.e. the start of the (i+1)'th block or past EOF).
+ *
+ * Note that size > 0, as a zero-sized file wouldn't ever
+ * have gotten here in the first place.
+ */
+static unsigned int
+do_compress(char *base, unsigned int offset, unsigned char const *name,
+ char *path, unsigned int size, unsigned int mode)
+{
+ unsigned long original_size, original_offset, new_size, blocks, curr;
+ long change;
+ char *start;
+ Bytef *p;
+
+ /* get uncompressed data */
+ start = do_mmap(path, size, mode);
+ if (start == NULL)
+ return offset;
+ p = (Bytef *) start;
+
+ original_size = size;
+ original_offset = offset;
+ blocks = (size - 1) / blksize + 1;
+ curr = offset + 4 * blocks;
+
+ total_blocks += blocks;
+
+ do {
+ uLongf len = 2 * blksize;
+ uLongf input = size;
+ if (input > blksize)
+ input = blksize;
+ size -= input;
+ if (!is_zero (p, input)) {
+ compress((Bytef *)(base + curr), &len, p, input);
+ curr += len;
+ }
+ p += input;
+
+ if (len > blksize*2) {
+ /* (I don't think this can happen with zlib.) */
+ printf(_("AIEEE: block \"compressed\" to > "
+ "2*blocklength (%ld)\n"),
+ len);
+ exit(MKFS_EX_ERROR);
+ }
+
+ *(uint32_t *) (base + offset) = u32_toggle_endianness(cramfs_is_big_endian, curr);
+ offset += 4;
+ } while (size);
+
+ do_munmap(start, original_size, mode);
+
+ curr = (curr + 3) & ~3;
+ new_size = curr - original_offset;
+ /* TODO: Arguably, original_size in these 2 lines should be
+ st_blocks * 512. But if you say that, then perhaps
+ administrative data should also be included in both. */
+ change = new_size - original_size;
+ if (verbose)
+ printf(_("%6.2f%% (%+ld bytes)\t%s\n"),
+ (change * 100) / (double) original_size, change, name);
+
+ return curr;
+}
+
+
+/*
+ * Traverse the entry tree, writing data for every item that has
+ * non-null entry->path (i.e. every symlink and non-empty
+ * regfile).
+ */
+static unsigned int
+write_data(struct entry *entry, char *base, unsigned int offset) {
+ struct entry *e;
+
+ for (e = entry; e; e = e->next) {
+ if (e->path) {
+ if (e->same) {
+ set_data_offset(e, base, e->same->offset);
+ e->offset = e->same->offset;
+ } else if (e->size) {
+ set_data_offset(e, base, offset);
+ e->offset = offset;
+ offset = do_compress(base, offset, e->name,
+ e->path, e->size,e->mode);
+ }
+ } else if (e->child)
+ offset = write_data(e->child, base, offset);
+ }
+ return offset;
+}
+
+static unsigned int write_file(char *file, char *base, unsigned int offset)
+{
+ int fd;
+ char *buf;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0)
+ err(MKFS_EX_ERROR, _("cannot open %s"), file);
+ buf = mmap(NULL, image_length, PROT_READ, MAP_PRIVATE, fd, 0);
+ memcpy(base + offset, buf, image_length);
+ munmap(buf, image_length);
+ if (close (fd) < 0)
+ err(MKFS_EX_ERROR, _("cannot close file %s"), file);
+ /* Pad up the image_length to a 4-byte boundary */
+ while (image_length & 3) {
+ *(base + offset + image_length) = '\0';
+ image_length++;
+ }
+ return (offset + image_length);
+}
+
+/*
+ * Maximum size fs you can create is roughly 256MB. (The last file's
+ * data must begin within 256MB boundary but can extend beyond that.)
+ *
+ * Note that if you want it to fit in a ROM then you're limited to what the
+ * hardware and kernel can support (64MB?).
+ */
+static unsigned int
+maxfslen(void) {
+ return (((1 << CRAMFS_OFFSET_WIDTH) - 1) << 2) /* offset */
+ + (1 << CRAMFS_SIZE_WIDTH) - 1 /* filesize */
+ + (1 << CRAMFS_SIZE_WIDTH) * 4 / blksize; /* block pointers */
+}
+
+/*
+ * Usage:
+ *
+ * mkcramfs directory-name outfile
+ *
+ * where "directory-name" is simply the root of the directory
+ * tree that we want to generate a compressed filesystem out
+ * of.
+ */
+int main(int argc, char **argv)
+{
+ struct stat st; /* used twice... */
+ struct entry *root_entry;
+ char *rom_image;
+ ssize_t offset, written;
+ int fd;
+ /* initial guess (upper-bound) of required filesystem size */
+ loff_t fslen_ub = sizeof(struct cramfs_super);
+ unsigned int fslen_max;
+ char const *dirname, *outfile;
+ char *lockmode = 0;
+ uint32_t crc = crc32(0L, NULL, 0);
+ int c;
+ cramfs_is_big_endian = HOST_IS_BIG_ENDIAN; /* default is to use host order */
+
+ total_blocks = 0;
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ close_stdout_atexit();
+
+ if (argc > 1) {
+ /* first arg may be one of our standard longopts */
+ if (!strcmp(argv[1], "--help"))
+ usage();
+ if (!strcmp(argv[1], "--version")) {
+ print_version(EXIT_SUCCESS);
+ exit(MKFS_EX_OK);
+ }
+ }
+ strutils_set_exitcode(MKFS_EX_USAGE);
+
+ /* command line options */
+ while ((c = getopt(argc, argv, "hb:Ee:i:n:N:l::psVvz")) != EOF) {
+ switch (c) {
+ case 'h':
+ usage();
+ case 'b':
+ blksize = strtou32_or_err(optarg, _("invalid blocksize argument"));
+ break;
+ case 'E':
+ opt_errors = 1;
+ break;
+ case 'e':
+ opt_edition = strtou32_or_err(optarg, _("invalid edition number argument"));
+ break;
+ case 'N':
+ if (strcmp(optarg, "big") == 0)
+ cramfs_is_big_endian = 1;
+ else if (strcmp(optarg, "little") == 0)
+ cramfs_is_big_endian = 0;
+ else if (strcmp(optarg, "host") == 0)
+ /* default */ ;
+ else
+ errx(MKFS_EX_USAGE, _("invalid endianness given;"
+ " must be 'big', 'little', or 'host'"));
+ break;
+ case 'i':
+ opt_image = optarg;
+ if (lstat(opt_image, &st) < 0)
+ err(MKFS_EX_USAGE, _("stat of %s failed"), opt_image);
+ image_length = st.st_size; /* may be padded later */
+ fslen_ub += (image_length + 3); /* 3 is for padding */
+ break;
+ case 'l':
+ lockmode = "1";
+ if (optarg) {
+ if (*optarg == '=')
+ optarg++;
+ lockmode = optarg;
+ }
+ break;
+ case 'n':
+ opt_name = optarg;
+ break;
+ case 'p':
+ opt_pad = PAD_SIZE;
+ fslen_ub += PAD_SIZE;
+ break;
+ case 's':
+ /* old option, ignored */
+ break;
+ case 'V':
+ print_version(MKFS_EX_OK);
+ case 'v':
+ verbose = 1;
+ break;
+ case 'z':
+ opt_holes = 1;
+ break;
+ default:
+ errtryhelp(MKFS_EX_USAGE);
+ }
+ }
+
+ if ((argc - optind) != 2) {
+ warnx(_("bad usage"));
+ errtryhelp(MKFS_EX_USAGE);
+ }
+ dirname = argv[optind];
+ outfile = argv[optind + 1];
+
+ if (blksize == 0)
+ blksize = getpagesize();
+
+ if (stat(dirname, &st) < 0)
+ err(MKFS_EX_USAGE, _("stat of %s failed"), dirname);
+ fd = open(outfile, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+ if (fd < 0)
+ err(MKFS_EX_USAGE, _("cannot open %s"), outfile);
+
+ if (blkdev_lock(fd, outfile, lockmode) != 0)
+ exit(MKFS_EX_ERROR);
+
+ root_entry = xcalloc(1, sizeof(struct entry));
+ root_entry->mode = st.st_mode;
+ root_entry->uid = st.st_uid;
+ root_entry->gid = st.st_gid;
+
+ root_entry->size = parse_directory(root_entry, dirname, &root_entry->child, &fslen_ub);
+
+ /* find duplicate files */
+ eliminate_doubles(root_entry,root_entry, &fslen_ub);
+
+ /* always allocate a multiple of blksize bytes because that's
+ what we're going to write later on */
+ fslen_ub = ((fslen_ub - 1) | (blksize - 1)) + 1;
+ fslen_max = maxfslen();
+
+ if (fslen_ub > fslen_max) {
+ warnx( _("warning: guestimate of required size (upper bound) "
+ "is %lldMB, but maximum image size is %uMB. "
+ "We might die prematurely."),
+ (long long)fslen_ub >> 20,
+ fslen_max >> 20);
+ fslen_ub = fslen_max;
+ }
+
+ /* TODO: Why do we use a private/anonymous mapping here
+ followed by a write below, instead of just a shared mapping
+ and a couple of ftruncate calls? Is it just to save us
+ having to deal with removing the file afterwards? If we
+ really need this huge anonymous mapping, we ought to mmap
+ in smaller chunks, so that the user doesn't need nn MB of
+ RAM free. If the reason is to be able to write to
+ un-mmappable block devices, then we could try shared mmap
+ and revert to anonymous mmap if the shared mmap fails. */
+ rom_image = mmap(NULL,
+ fslen_ub?fslen_ub:1,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ -1, 0);
+
+ if (-1 == (int) (long) rom_image)
+ err(MKFS_EX_ERROR, _("ROM image map"));
+
+ /* Skip the first opt_pad bytes for boot loader code */
+ offset = opt_pad;
+ memset(rom_image, 0x00, opt_pad);
+
+ /* Skip the superblock and come back to write it later. */
+ offset += sizeof(struct cramfs_super);
+
+ /* Insert a file image. */
+ if (opt_image) {
+ if (verbose)
+ printf(_("Including: %s\n"), opt_image);
+ offset = write_file(opt_image, rom_image, offset);
+ }
+
+ offset = write_directory_structure(root_entry->child, rom_image, offset);
+ if (verbose)
+ printf(_("Directory data: %zd bytes\n"), offset);
+
+ offset = write_data(root_entry, rom_image, offset);
+
+ /* We always write a multiple of blksize bytes, so that
+ losetup works. */
+ offset = ((offset - 1) | (blksize - 1)) + 1;
+ if (verbose)
+ printf(_("Everything: %zd kilobytes\n"), offset >> 10);
+
+ /* Write the superblock now that we can fill in all of the fields. */
+ write_superblock(root_entry, rom_image+opt_pad, offset);
+ if (verbose)
+ printf(_("Super block: %zd bytes\n"),
+ sizeof(struct cramfs_super));
+
+ /* Put the checksum in. */
+ crc = crc32(crc, (unsigned char *) (rom_image+opt_pad), (offset-opt_pad));
+ ((struct cramfs_super *) (rom_image+opt_pad))->fsid.crc = u32_toggle_endianness(cramfs_is_big_endian, crc);
+ if (verbose)
+ printf(_("CRC: %x\n"), crc);
+
+ /* Check to make sure we allocated enough space. */
+ if (fslen_ub < offset)
+ errx(MKFS_EX_ERROR,
+ _("not enough space allocated for ROM image "
+ "(%lld allocated, %zu used)"),
+ (long long) fslen_ub, offset);
+
+ written = write(fd, rom_image, offset);
+ if (offset != written)
+ errx(MKFS_EX_ERROR, _("ROM image write failed (%zd %zd)"),
+ written, offset);
+ if (close_fd(fd) != 0)
+ err(MKFS_EX_ERROR, _("ROM image"));
+
+ /*
+ * (These warnings used to come at the start, but they scroll off
+ * the screen too quickly.)
+ */
+ if (warn_namelen)
+ /* Can't happen when reading from ext2fs. */
+ /* Bytes, not chars: think UTF8. */
+ warnx(_("warning: filenames truncated to %u bytes."), MAX_INPUT_NAMELEN);
+ if (warn_skip)
+ warnx(_("warning: files were skipped due to errors."));
+ if (warn_size)
+ warnx(_("warning: file sizes truncated to %luMB "
+ "(minus 1 byte)."), 1L << (CRAMFS_SIZE_WIDTH - 20));
+ if (warn_uid)
+ /* (not possible with current Linux versions) */
+ warnx(_("warning: uids truncated to %u bits. "
+ "(This may be a security concern.)"), CRAMFS_UID_WIDTH);
+ if (warn_gid)
+ warnx(_("warning: gids truncated to %u bits. "
+ "(This may be a security concern.)"), CRAMFS_GID_WIDTH);
+ if (warn_dev)
+ warnx(_("WARNING: device numbers truncated to %u bits. "
+ "This almost certainly means\n"
+ "that some device files will be wrong."),
+ CRAMFS_OFFSET_WIDTH);
+ if (opt_errors &&
+ (warn_namelen|warn_skip|warn_size|warn_uid|warn_gid|warn_dev))
+ exit(MKFS_EX_ERROR);
+
+ return MKFS_EX_OK;
+}