--- /dev/null
+/*
+ *
+ * (c) 2008-2009 Laurent Vivier <Laurent@lvivier.info>
+ *
+ * This file has been copied from EMILE, http://emile.sf.net
+ *
+ */
+
+#include "libext2.h"
+#include "ext2_utils.h"
+#include "libopenbios/bindings.h"
+#include "libc/diskio.h"
+#include "libc/byteorder.h"
+
+int ext2_probe(int fd, long long offset)
+{
+ struct ext2_super_block *super;
+
+ super = (struct ext2_super_block*)malloc(sizeof(struct ext2_super_block));
+ seek_io(fd, 2 * 512 + offset);
+ read_io(fd, super, sizeof (*super));
+
+ if (__le16_to_cpu(super->s_magic) != EXT2_SUPER_MAGIC) {
+ free(super);
+ return 0;
+ }
+
+ free(super);
+ return -1;
+}
+
+void ext2_get_super(int fd, struct ext2_super_block *super)
+{
+ seek_io(fd, 2 * 512);
+ read_io(fd, super, sizeof (*super));
+
+ super->s_inodes_count = __le32_to_cpu(super->s_inodes_count);
+ super->s_blocks_count = __le32_to_cpu(super->s_blocks_count);
+ super->s_r_blocks_count = __le32_to_cpu(super->s_r_blocks_count);
+ super->s_free_blocks_count = __le32_to_cpu(super->s_free_blocks_count);
+ super->s_free_inodes_count = __le32_to_cpu(super->s_free_inodes_count);
+ super->s_first_data_block = __le32_to_cpu(super->s_first_data_block);
+ super->s_log_block_size = __le32_to_cpu(super->s_log_block_size);
+ super->s_log_frag_size = __le32_to_cpu(super->s_log_frag_size);
+ super->s_blocks_per_group = __le32_to_cpu(super->s_blocks_per_group);
+ super->s_frags_per_group = __le32_to_cpu(super->s_frags_per_group);
+ super->s_inodes_per_group = __le32_to_cpu(super->s_inodes_per_group);
+ super->s_mtime = __le32_to_cpu(super->s_mtime);
+ super->s_wtime = __le32_to_cpu(super->s_wtime);
+ super->s_mnt_count = __le16_to_cpu(super->s_mnt_count);
+ super->s_max_mnt_count = __le16_to_cpu(super->s_max_mnt_count);
+ super->s_magic = __le16_to_cpu(super->s_magic);
+ super->s_state = __le16_to_cpu(super->s_state);
+ super->s_errors = __le16_to_cpu(super->s_errors);
+ super->s_minor_rev_level = __le16_to_cpu(super->s_minor_rev_level);
+ super->s_lastcheck = __le32_to_cpu(super->s_lastcheck);
+ super->s_checkinterval = __le32_to_cpu(super->s_checkinterval);
+ super->s_creator_os = __le32_to_cpu(super->s_creator_os);
+ super->s_rev_level = __le32_to_cpu(super->s_rev_level);
+ super->s_def_resuid = __le16_to_cpu(super->s_def_resuid);
+ super->s_def_resgid = __le16_to_cpu(super->s_def_resgid);
+ super->s_first_ino = __le32_to_cpu(super->s_first_ino);
+ super->s_inode_size = __le16_to_cpu(super->s_inode_size);
+ super->s_block_group_nr = __le16_to_cpu(super->s_block_group_nr);
+ super->s_feature_compat = __le32_to_cpu(super->s_feature_compat);
+ super->s_feature_incompat = __le32_to_cpu(super->s_feature_incompat);
+ super->s_feature_ro_compat = __le32_to_cpu(super->s_feature_ro_compat);
+ super->s_algorithm_usage_bitmap =
+ __le32_to_cpu(super->s_algorithm_usage_bitmap);
+ super->s_journal_inum = __le32_to_cpu(super->s_journal_inum);
+ super->s_journal_dev = __le32_to_cpu(super->s_journal_dev);
+ super->s_last_orphan = __le32_to_cpu(super->s_last_orphan);
+ super->s_hash_seed[0] = __le32_to_cpu(super->s_hash_seed[0]);
+ super->s_hash_seed[1] = __le32_to_cpu(super->s_hash_seed[1]);
+ super->s_hash_seed[2] = __le32_to_cpu(super->s_hash_seed[2]);
+ super->s_hash_seed[3] = __le32_to_cpu(super->s_hash_seed[3]);
+ super->s_default_mount_opts =
+ __le32_to_cpu(super->s_default_mount_opts);
+ super->s_first_meta_bg = __le32_to_cpu(super->s_first_meta_bg);
+}
+
+void ext2_read_block(ext2_VOLUME* volume, unsigned int fsblock)
+{
+ long long offset;
+
+ if (fsblock == volume->current)
+ return;
+
+ volume->current = fsblock;
+ offset = fsblock * EXT2_BLOCK_SIZE(volume->super);
+
+ seek_io(volume->fd, offset);
+ read_io(volume->fd, volume->buffer, EXT2_BLOCK_SIZE(volume->super));
+}
+
+void ext2_get_group_desc(ext2_VOLUME* volume,
+ int group_id, struct ext2_group_desc *gdp)
+{
+ unsigned int block, offset;
+ struct ext2_group_desc *le_gdp;
+
+ block = 1 + volume->super->s_first_data_block;
+ block += group_id / EXT2_DESC_PER_BLOCK(volume->super);
+ ext2_read_block(volume, block);
+
+ offset = group_id % EXT2_DESC_PER_BLOCK(volume->super);
+ offset *= sizeof(*gdp);
+
+ le_gdp = (struct ext2_group_desc *)(volume->buffer + offset);
+
+ gdp->bg_block_bitmap = __le32_to_cpu(le_gdp->bg_block_bitmap);
+ gdp->bg_inode_bitmap = __le32_to_cpu(le_gdp->bg_inode_bitmap);
+ gdp->bg_inode_table = __le32_to_cpu(le_gdp->bg_inode_table);
+ gdp->bg_free_blocks_count = __le16_to_cpu(le_gdp->bg_free_blocks_count);
+ gdp->bg_free_inodes_count = __le16_to_cpu(le_gdp->bg_free_inodes_count);
+ gdp->bg_used_dirs_count = __le16_to_cpu(le_gdp->bg_used_dirs_count);
+}
+
+int ext2_get_inode(ext2_VOLUME* volume,
+ unsigned int ino, struct ext2_inode *inode)
+{
+ struct ext2_group_desc desc;
+ unsigned int block;
+ unsigned int group_id;
+ unsigned int offset;
+ struct ext2_inode *le_inode;
+ int i;
+
+ ino--;
+
+ group_id = ino / EXT2_INODES_PER_GROUP(volume->super);
+ ext2_get_group_desc(volume, group_id, &desc);
+
+ ino %= EXT2_INODES_PER_GROUP(volume->super);
+
+ block = desc.bg_inode_table;
+ block += ino / (EXT2_BLOCK_SIZE(volume->super) /
+ EXT2_INODE_SIZE(volume->super));
+ ext2_read_block(volume, block);
+
+ offset = ino % (EXT2_BLOCK_SIZE(volume->super) /
+ EXT2_INODE_SIZE(volume->super));
+ offset *= EXT2_INODE_SIZE(volume->super);
+
+ le_inode = (struct ext2_inode *)(volume->buffer + offset);
+
+ inode->i_mode = __le16_to_cpu(le_inode->i_mode);
+ inode->i_uid = __le16_to_cpu(le_inode->i_uid);
+ inode->i_size = __le32_to_cpu(le_inode->i_size);
+ inode->i_atime = __le32_to_cpu(le_inode->i_atime);
+ inode->i_ctime = __le32_to_cpu(le_inode->i_ctime);
+ inode->i_mtime = __le32_to_cpu(le_inode->i_mtime);
+ inode->i_dtime = __le32_to_cpu(le_inode->i_dtime);
+ inode->i_gid = __le16_to_cpu(le_inode->i_gid);
+ inode->i_links_count = __le16_to_cpu(le_inode->i_links_count);
+ inode->i_blocks = __le32_to_cpu(le_inode->i_blocks);
+ inode->i_flags = __le32_to_cpu(le_inode->i_flags);
+ if (S_ISLNK(inode->i_mode)) {
+ memcpy(inode->i_block, le_inode->i_block, EXT2_N_BLOCKS * 4);
+ } else {
+ for (i = 0; i < EXT2_N_BLOCKS; i++)
+ inode->i_block[i] = __le32_to_cpu(le_inode->i_block[i]);
+ }
+ inode->i_generation = __le32_to_cpu(le_inode->i_generation);
+ inode->i_file_acl = __le32_to_cpu(le_inode->i_file_acl);
+ inode->i_dir_acl = __le32_to_cpu(le_inode->i_dir_acl);
+ inode->i_faddr = __le32_to_cpu(le_inode->i_faddr);
+ inode->osd2.linux2.l_i_frag = le_inode->osd2.linux2.l_i_frag;
+ inode->osd2.linux2.l_i_fsize = le_inode->osd2.linux2.l_i_fsize;
+ inode->osd2.linux2.l_i_uid_high =
+ __le16_to_cpu(le_inode->osd2.linux2.l_i_uid_high);
+ inode->osd2.linux2.l_i_gid_high =
+ __le16_to_cpu(le_inode->osd2.linux2.l_i_gid_high);
+ return 0;
+}
+
+unsigned int ext2_get_block_addr(ext2_VOLUME* volume, struct ext2_inode *inode,
+ unsigned int logical)
+{
+ unsigned int physical;
+ unsigned int addr_per_block;
+
+ /* direct */
+
+ if (logical < EXT2_NDIR_BLOCKS) {
+ physical = inode->i_block[logical];
+ return physical;
+ }
+
+ /* indirect */
+
+ logical -= EXT2_NDIR_BLOCKS;
+
+ addr_per_block = EXT2_ADDR_PER_BLOCK (volume->super);
+ if (logical < addr_per_block) {
+ ext2_read_block(volume, inode->i_block[EXT2_IND_BLOCK]);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)[logical]);
+ return physical;
+ }
+
+ /* double indirect */
+
+ logical -= addr_per_block;
+
+ if (logical < addr_per_block * addr_per_block) {
+ ext2_read_block(volume, inode->i_block[EXT2_DIND_BLOCK]);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)
+ [logical / addr_per_block]);
+ ext2_read_block(volume, physical);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)
+ [logical % addr_per_block]);
+ return physical;
+ }
+
+ /* triple indirect */
+
+ logical -= addr_per_block * addr_per_block;
+ ext2_read_block(volume, inode->i_block[EXT2_DIND_BLOCK]);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)
+ [logical / (addr_per_block * addr_per_block)]);
+ ext2_read_block(volume, physical);
+ logical = logical % (addr_per_block * addr_per_block);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)[logical / addr_per_block]);
+ ext2_read_block(volume, physical);
+ physical = __le32_to_cpu(((unsigned int *)volume->buffer)[logical % addr_per_block]);
+ return physical;
+}
+
+int ext2_read_data(ext2_VOLUME* volume, struct ext2_inode *inode,
+ off_t offset, char *buffer, size_t length)
+{
+ unsigned int logical, physical;
+ int blocksize = EXT2_BLOCK_SIZE(volume->super);
+ int shift;
+ size_t read;
+
+ if (offset >= inode->i_size)
+ return -1;
+
+ if (offset + length >= inode->i_size)
+ length = inode->i_size - offset;
+
+ read = 0;
+ logical = offset / blocksize;
+ shift = offset % blocksize;
+
+ if (shift) {
+ physical = ext2_get_block_addr(volume, inode, logical);
+ ext2_read_block(volume, physical);
+
+ if (length < blocksize - shift) {
+ memcpy(buffer, volume->buffer + shift, length);
+ return length;
+ }
+ read += blocksize - shift;
+ memcpy(buffer, volume->buffer + shift, read);
+
+ buffer += read;
+ length -= read;
+ logical++;
+ }
+
+ while (length) {
+ physical = ext2_get_block_addr(volume, inode, logical);
+ ext2_read_block(volume, physical);
+
+ if (length < blocksize) {
+ memcpy(buffer, volume->buffer, length);
+ read += length;
+ return read;
+ }
+ memcpy(buffer, volume->buffer, blocksize);
+
+ buffer += blocksize;
+ length -= blocksize;
+ read += blocksize;
+ logical++;
+ }
+
+ return read;
+}
+
+off_t ext2_dir_entry(ext2_VOLUME *volume, struct ext2_inode *inode,
+ off_t index, struct ext2_dir_entry_2 *entry)
+{
+ int ret;
+
+ ret = ext2_read_data(volume, inode, index,
+ (char*)entry, sizeof(*entry));
+ if (ret == -1)
+ return -1;
+
+ entry->inode = __le32_to_cpu(entry->inode);
+ entry->rec_len = __le16_to_cpu(entry->rec_len);
+ return index + entry->rec_len;
+}
+
+unsigned int ext2_seek_name(ext2_VOLUME *volume, const char *name)
+{
+ struct ext2_inode inode;
+ int ret;
+ unsigned int ino;
+ off_t index;
+ struct ext2_dir_entry_2 entry;
+
+ ino = EXT2_ROOT_INO;
+ while(1) {
+ while (*name == '\\')
+ name++;
+ if (!*name)
+ break;
+ ret = ext2_get_inode(volume, ino, &inode);
+ if (ret == -1)
+ return 0;
+ index = 0;
+ while (1) {
+ index = ext2_dir_entry(volume, &inode, index, &entry);
+ if (index == -1)
+ return 0;
+ ret = strncmp(name, entry.name, entry.name_len);
+ if (ret == 0 &&
+ (name[entry.name_len] == 0 ||
+ name[entry.name_len] == '\\')) {
+ ino = entry.inode;
+ break;
+ }
+ }
+ name += entry.name_len;
+ }
+
+ return ino;
+}
Code Review / kvmfornfv.git / blobdiff