Remove unused function

[project/make_ext4fs.git] / make_ext4fs.c

/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "ext4_utils.h"
#include "allocate.h"
#include "contents.h"
#include "uuid.h"
#include "wipe.h"

#include <sparse/sparse.h>

#include <assert.h>
#include <dirent.h>
#include <fcntl.h>
#include <inttypes.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>

/* TODO: Not implemented:
   Allocating blocks in the same block group as the file inode
   Hash or binary tree directories
 */

static int filter_dot(const struct dirent *d)
{
        return (strcmp(d->d_name, "..") && strcmp(d->d_name, "."));
}

/* Read a local directory and create the same tree in the generated filesystem.
   Calls itself recursively with each directory in the given directory.
   full_path is an absolute or relative path, with a trailing slash, to the
   directory on disk that should be copied, or NULL if this is a directory
   that does not exist on disk (e.g. lost+found).
   dir_path is an absolute path, with trailing slash, to the same directory
   if the image were mounted at the specified mount point */
static u32 build_directory_structure(const char *full_path, const char *dir_path,
                u32 dir_inode, fs_config_func_t fs_config_func,
                int verbose, time_t fixed_time)
{
        int entries = 0;
        struct dentry *dentries;
        struct dirent **namelist = NULL;
        struct stat stat;
        int ret;
        int i;
        u32 inode;
        u32 entry_inode;
        u32 dirs = 0;
        bool needs_lost_and_found = false;

        if (full_path) {
                entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort);
                if (entries < 0) {
#ifdef __GLIBC__
                        /* The scandir function implemented in glibc has a bug that makes it
                           erroneously fail with ENOMEM under certain circumstances.
                           As a workaround we can retry the scandir call with the same arguments.
                           GLIBC BZ: https://sourceware.org/bugzilla/show_bug.cgi?id=17804 */
                        if (errno == ENOMEM)
                                entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort);
#endif
                        if (entries < 0) {
                                error_errno("scandir");
                                return EXT4_ALLOCATE_FAILED;
                        }
                }
        }

        if (dir_inode == 0) {
                /* root directory, check if lost+found already exists */
                for (i = 0; i < entries; i++)
                        if (strcmp(namelist[i]->d_name, "lost+found") == 0)
                                break;
                if (i == entries)
                        needs_lost_and_found = true;
        }

        dentries = calloc(entries, sizeof(struct dentry));
        if (dentries == NULL)
                critical_error_errno("malloc");

        for (i = 0; i < entries; i++) {
                dentries[i].filename = strdup(namelist[i]->d_name);
                if (dentries[i].filename == NULL)
                        critical_error_errno("strdup");

                asprintf(&dentries[i].path, "%s%s", dir_path, namelist[i]->d_name);
                asprintf(&dentries[i].full_path, "%s%s", full_path, namelist[i]->d_name);

                free(namelist[i]);

                ret = lstat(dentries[i].full_path, &stat);
                if (ret < 0) {
                        error_errno("lstat");
                        i--;
                        entries--;
                        continue;
                }

                dentries[i].size = stat.st_size;
                dentries[i].mode = stat.st_mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO);
                if (fixed_time == -1) {
                        dentries[i].mtime = stat.st_mtime;
                } else {
                        dentries[i].mtime = fixed_time;
                }
                uint64_t capabilities;
                if (fs_config_func != NULL) {
                        unsigned int mode = 0;
                        unsigned int uid = 0;
                        unsigned int gid = 0;
                        int dir = S_ISDIR(stat.st_mode);
                        if (fs_config_func(dentries[i].path, dir, &uid, &gid, &mode, &capabilities)) {
                                dentries[i].mode = mode;
                                dentries[i].uid = uid;
                                dentries[i].gid = gid;
                                dentries[i].capabilities = capabilities;
                        }
                }

                if (S_ISREG(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_REG_FILE;
                } else if (S_ISDIR(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_DIR;
                        dirs++;
                } else if (S_ISCHR(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_CHRDEV;
                } else if (S_ISBLK(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_BLKDEV;
                } else if (S_ISFIFO(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_FIFO;
                } else if (S_ISSOCK(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_SOCK;
                } else if (S_ISLNK(stat.st_mode)) {
                        dentries[i].file_type = EXT4_FT_SYMLINK;
                        dentries[i].link = calloc(info.block_size, 1);
                        readlink(dentries[i].full_path, dentries[i].link, info.block_size - 1);
                } else {
                        error("unknown file type on %s", dentries[i].path);
                        i--;
                        entries--;
                }
        }
        free(namelist);

        if (needs_lost_and_found) {
                /* insert a lost+found directory at the beginning of the dentries */
                struct dentry *tmp = calloc(entries + 1, sizeof(struct dentry));
                memset(tmp, 0, sizeof(struct dentry));
                memcpy(tmp + 1, dentries, entries * sizeof(struct dentry));
                dentries = tmp;

                dentries[0].filename = strdup("lost+found");
                asprintf(&dentries[0].path, "%slost+found", dir_path);
                dentries[0].full_path = NULL;
                dentries[0].size = 0;
                dentries[0].mode = S_IRWXU;
                dentries[0].file_type = EXT4_FT_DIR;
                dentries[0].uid = 0;
                dentries[0].gid = 0;
                entries++;
                dirs++;
        }

        inode = make_directory(dir_inode, entries, dentries, dirs);

        for (i = 0; i < entries; i++) {
                if (dentries[i].file_type == EXT4_FT_REG_FILE) {
                        entry_inode = make_file(dentries[i].full_path, dentries[i].size);
                } else if (dentries[i].file_type == EXT4_FT_DIR) {
                        char *subdir_full_path = NULL;
                        char *subdir_dir_path;
                        if (dentries[i].full_path) {
                                ret = asprintf(&subdir_full_path, "%s/", dentries[i].full_path);
                                if (ret < 0)
                                        critical_error_errno("asprintf");
                        }
                        ret = asprintf(&subdir_dir_path, "%s/", dentries[i].path);
                        if (ret < 0)
                                critical_error_errno("asprintf");
                        entry_inode = build_directory_structure(subdir_full_path,
                                        subdir_dir_path, inode, fs_config_func, verbose, fixed_time);
                        free(subdir_full_path);
                        free(subdir_dir_path);
                } else if (dentries[i].file_type == EXT4_FT_SYMLINK) {
                        entry_inode = make_link(dentries[i].link);
                } else if (dentries[i].file_type == EXT4_FT_CHRDEV ||
                           dentries[i].file_type == EXT4_FT_BLKDEV ||
                           dentries[i].file_type == EXT4_FT_SOCK ||
                           dentries[i].file_type == EXT4_FT_FIFO) {
                        entry_inode = make_special(dentries[i].full_path);
                } else {
                        error("unknown file type on %s", dentries[i].path);
                        entry_inode = 0;
                }
                *dentries[i].inode = entry_inode;

                ret = inode_set_permissions(entry_inode, dentries[i].mode,
                        dentries[i].uid, dentries[i].gid,
                        dentries[i].mtime);
                if (ret)
                        error("failed to set permissions on %s\n", dentries[i].path);

                ret = inode_set_capabilities(entry_inode, dentries[i].capabilities);
                if (ret)
                        error("failed to set capability on %s\n", dentries[i].path);

                free(dentries[i].path);
                free(dentries[i].full_path);
                free(dentries[i].link);
                free((void *)dentries[i].filename);
        }

        free(dentries);
        return inode;
}

static u32 compute_block_size()
{
        return 4096;
}

static u32 compute_journal_blocks()
{
        u32 journal_blocks = DIV_ROUND_UP(info.len, info.block_size) / 64;
        if (journal_blocks < 1024)
                journal_blocks = 1024;
        if (journal_blocks > 32768)
                journal_blocks = 32768;
        return journal_blocks;
}

static u32 compute_blocks_per_group()
{
        return info.block_size * 8;
}

static u32 compute_inodes()
{
        return DIV_ROUND_UP(info.len, info.block_size) / 4;
}

static u32 compute_inodes_per_group()
{
        u32 blocks = DIV_ROUND_UP(info.len, info.block_size);
        u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group);
        u32 inodes = DIV_ROUND_UP(info.inodes, block_groups);
        inodes = EXT4_ALIGN(inodes, (info.block_size / info.inode_size));

        /* After properly rounding up the number of inodes/group,
         * make sure to update the total inodes field in the info struct.
         */
        info.inodes = inodes * block_groups;

        return inodes;
}

static u32 compute_bg_desc_reserve_blocks()
{
        u32 blocks = DIV_ROUND_UP(info.len, info.block_size);
        u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group);
        u32 bg_desc_blocks = DIV_ROUND_UP(block_groups * sizeof(struct ext2_group_desc),
                        info.block_size);

        u32 bg_desc_reserve_blocks =
                        DIV_ROUND_UP(block_groups * 1024 * sizeof(struct ext2_group_desc),
                                        info.block_size) - bg_desc_blocks;

        if (bg_desc_reserve_blocks > info.block_size / sizeof(u32))
                bg_desc_reserve_blocks = info.block_size / sizeof(u32);

        return bg_desc_reserve_blocks;
}

/* return a newly-malloc'd string that is a copy of str.  The new string
   is guaranteed to have a trailing slash.  If absolute is true, the new string
   is also guaranteed to have a leading slash.
*/
static char *canonicalize_slashes(const char *str, bool absolute)
{
        char *ret;
        int len = strlen(str);
        int newlen = len;
        char *ptr;

        if (len == 0) {
                if (absolute)
                        return strdup("/");
                else
                        return strdup("");
        }

        if (str[0] != '/' && absolute) {
                newlen++;
        }
        if (str[len - 1] != '/') {
                newlen++;
        }
        ret = malloc(newlen + 1);
        if (!ret) {
                critical_error("malloc");
        }

        ptr = ret;
        if (str[0] != '/' && absolute) {
                *ptr++ = '/';
        }

        strcpy(ptr, str);
        ptr += len;

        if (str[len - 1] != '/') {
                *ptr++ = '/';
        }

        if (ptr != ret + newlen) {
                critical_error("assertion failed\n");
        }

        *ptr = '\0';

        return ret;
}

static char *canonicalize_abs_slashes(const char *str)
{
        return canonicalize_slashes(str, true);
}

static char *canonicalize_rel_slashes(const char *str)
{
        return canonicalize_slashes(str, false);
}

int make_ext4fs_internal(int fd, const char *_directory,
                                                 fs_config_func_t fs_config_func, int gzip,
                                                 int sparse, int crc, int wipe,
                                                 int verbose, time_t fixed_time,
                                                 FILE* block_list_file)
{
        u32 root_inode_num;
        u16 root_mode;
        char *directory = NULL;

        if (setjmp(setjmp_env))
                return EXIT_FAILURE; /* Handle a call to longjmp() */

        if (_directory == NULL) {
                fprintf(stderr, "Need a source directory\n");
                return EXIT_FAILURE;
        }

        directory = canonicalize_rel_slashes(_directory);

        if (info.len <= 0)
                info.len = get_file_size(fd);

        if (info.len <= 0) {
                fprintf(stderr, "Need size of filesystem\n");
                return EXIT_FAILURE;
        }

        if (info.block_size <= 0)
                info.block_size = compute_block_size();

        /* Round down the filesystem length to be a multiple of the block size */
        info.len &= ~((u64)info.block_size - 1);

        if (info.journal_blocks == 0)
                info.journal_blocks = compute_journal_blocks();

        if (info.no_journal == 0)
                info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL;
        else
                info.journal_blocks = 0;

        if (info.blocks_per_group <= 0)
                info.blocks_per_group = compute_blocks_per_group();

        if (info.inodes <= 0)
                info.inodes = compute_inodes();

        if (info.inode_size <= 0)
                info.inode_size = 256;

        if (info.label == NULL)
                info.label = "";

        info.inodes_per_group = compute_inodes_per_group();

        info.feat_compat |=
                        EXT4_FEATURE_COMPAT_RESIZE_INODE |
                        EXT4_FEATURE_COMPAT_EXT_ATTR;

        info.feat_ro_compat |=
                        EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |
                        EXT4_FEATURE_RO_COMPAT_LARGE_FILE |
                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM;

        info.feat_incompat |=
                        EXT4_FEATURE_INCOMPAT_EXTENTS |
                        EXT4_FEATURE_INCOMPAT_FILETYPE;


        info.bg_desc_reserve_blocks = compute_bg_desc_reserve_blocks();

        printf("Creating filesystem with parameters:\n");
        printf("    Size: %"PRIu64"\n", info.len);
        printf("    Block size: %d\n", info.block_size);
        printf("    Blocks per group: %d\n", info.blocks_per_group);
        printf("    Inodes per group: %d\n", info.inodes_per_group);
        printf("    Inode size: %d\n", info.inode_size);
        printf("    Journal blocks: %d\n", info.journal_blocks);
        printf("    Label: %s\n", info.label);

        ext4_create_fs_aux_info();

        printf("    Blocks: %"PRIu64"\n", aux_info.len_blocks);
        printf("    Block groups: %d\n", aux_info.groups);
        printf("    Reserved blocks: %"PRIu64"\n",  (aux_info.len_blocks / 100) * info.reserve_pcnt);
        printf("    Reserved block group size: %d\n", info.bg_desc_reserve_blocks);

        ext4_sparse_file = sparse_file_new(info.block_size, info.len);

        block_allocator_init();

        ext4_fill_in_sb();

        if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED)
                error("failed to reserve first 10 inodes");

        if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL)
                ext4_create_journal_inode();

        if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE)
                ext4_create_resize_inode();

        root_inode_num = build_directory_structure(directory, "", 0,
                fs_config_func, verbose, fixed_time);

        root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;
        inode_set_permissions(root_inode_num, root_mode, 0, 0, 0);

        ext4_update_free();

        ext4_queue_sb();

        if (block_list_file) {
                size_t dirlen = strlen(directory);
                struct block_allocation* p = get_saved_allocation_chain();
                while (p) {
                        if (strncmp(p->filename, directory, dirlen) == 0) {
                                fprintf(block_list_file, "%s", p->filename + dirlen);
                        } else {
                                fprintf(block_list_file, "%s", p->filename);
                        }
                        print_blocks(block_list_file, p);
                        struct block_allocation* pn = p->next;
                        free_alloc(p);
                        p = pn;
                }
        }

        printf("Created filesystem with %d/%d inodes and %d/%d blocks\n",
                        aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count,
                        aux_info.sb->s_inodes_count,
                        aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
                        aux_info.sb->s_blocks_count_lo);

        if (wipe && WIPE_IS_SUPPORTED) {
                wipe_block_device(fd, info.len);
        }

        write_ext4_image(fd, gzip, sparse, crc);

        sparse_file_destroy(ext4_sparse_file);
        ext4_sparse_file = NULL;

        free(directory);

        return 0;
}