From 36205a44d68576a158c9f233a17abe5f8a3c63a0 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sun, 15 Sep 2019 15:59:01 +0200 Subject: Add helper function to directory writer to create a basic inode Signed-off-by: David Oberhollenzer --- include/sqfs/dir.h | 59 +++++++++++++++++++++++++++++++++------ lib/sqfs/dir_writer.c | 50 +++++++++++++++++++++++++++++++++ lib/sqfshelper/serialize_fstree.c | 53 +++++++++++++++++++++++------------ 3 files changed, 135 insertions(+), 27 deletions(-) diff --git a/include/sqfs/dir.h b/include/sqfs/dir.h index ff53ce5..18950df 100644 --- a/include/sqfs/dir.h +++ b/include/sqfs/dir.h @@ -176,7 +176,7 @@ extern "C" { /** * @brief Create a directory writer. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param dm A pointer to a meta data writer that the generated directory * entries should be written to. @@ -189,7 +189,7 @@ SQFS_API sqfs_dir_writer_t *sqfs_dir_writer_create(sqfs_meta_writer_t *dm); /** * @brief Destroy a directory writer and free all its memory. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param writer A pointer to a directory writer object. */ @@ -199,7 +199,7 @@ SQFS_API void sqfs_dir_writer_destroy(sqfs_dir_writer_t *writer); * @brief Begin writing a directory, i.e. reset and initialize all internal * state neccessary. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param writer A pointer to a directory writer object. * @@ -210,7 +210,7 @@ SQFS_API int sqfs_dir_writer_begin(sqfs_dir_writer_t *writer); /** * @brief Add add a directory entry. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param writer A pointer to a directory writer object. * @param name The name of the directory entry. @@ -232,7 +232,7 @@ SQFS_API int sqfs_dir_writer_add_entry(sqfs_dir_writer_t *writer, * @brief Finish writing a directory listing and write everything out to the * meta data writer. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param writer A pointer to a directory writer object. * @@ -244,7 +244,7 @@ SQFS_API int sqfs_dir_writer_end(sqfs_dir_writer_t *writer); * @brief Get the total, uncompressed size of the last written * directory in bytes. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * Call this function after @ref sqfs_dir_writer_end to get the uncompressed * size of the directory listing that is required for the directory inodes. @@ -256,10 +256,25 @@ SQFS_API int sqfs_dir_writer_end(sqfs_dir_writer_t *writer); */ SQFS_API size_t sqfs_dir_writer_get_size(const sqfs_dir_writer_t *writer); +/** + * @brief Get the numer of entries written to the last directory. + * + * @memberof sqfs_dir_writer_t + * + * Call this function after @ref sqfs_dir_writer_end to get the total + * number of entries written to the directory. + * + * @param writer A pointer to a directory writer object. + * + * @return The number of entries in the directory. + */ +SQFS_API +size_t sqfs_dir_writer_get_entry_count(const sqfs_dir_writer_t *writer); + /** * @brief Get the location of the last written directory. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * Call this function after @ref sqfs_dir_writer_end to get the location of * the directory listing that is required for the directory inodes. @@ -275,7 +290,7 @@ sqfs_dir_writer_get_dir_reference(const sqfs_dir_writer_t *writer); /** * @brief Get the size of the index of the last written directory. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * Call this function after @ref sqfs_dir_writer_end to get the size of * the directory index that is required for extended directory inodes. @@ -290,7 +305,7 @@ SQFS_API size_t sqfs_dir_writer_get_index_size(const sqfs_dir_writer_t *writer); * @brief Write the index of the index of the last written directory to * a meta data writer after the extended directory inode. * - * @memberof sqfs_dir_writer_create + * @memberof sqfs_dir_writer_t * * @param writer A pointer to a directory writer object. * @param im A pointer to a meta data writer to write the index to. @@ -300,6 +315,32 @@ SQFS_API size_t sqfs_dir_writer_get_index_size(const sqfs_dir_writer_t *writer); SQFS_API int sqfs_dir_writer_write_index(const sqfs_dir_writer_t *writer, sqfs_meta_writer_t *im); +/** + * @brief Helper function for creating an inode from the last directory. + * + * @memberof sqfs_dir_writer_t + * + * Call this function after @ref sqfs_dir_writer_end to create a bare bones + * inode structure for the directory. The directory information is filled in + * completely and the type is set, the rest of the basic information such as + * permission bits, owner and timestamp is left untouched. + * + * If the generated inode is an extended directory inode, you can use another + * convenience function called @ref sqfs_dir_writer_write_index to write the + * index meta data after writing the inode itself. + * + * @param writer A pointer to a directory writer object. + * @param hlinks The number of hard links pointing to the directory. + * @param xattr If set to something other than 0xFFFFFFFF, an extended + * directory inode is created with xattr index set. + * @param parent_ino The inode number of the parent directory. + * + * @return A generic inode or NULL on allocation failure. + */ +SQFS_API sqfs_inode_generic_t +*sqfs_dir_writer_create_inode(const sqfs_dir_writer_t *writer, size_t hlinks, + uint32_t xattr, uint32_t parent_ino); + #ifdef __cplusplus } #endif diff --git a/lib/sqfs/dir_writer.c b/lib/sqfs/dir_writer.c index d7bb590..47e6b62 100644 --- a/lib/sqfs/dir_writer.c +++ b/lib/sqfs/dir_writer.c @@ -45,6 +45,7 @@ struct sqfs_dir_writer_t { uint64_t dir_ref; size_t dir_size; size_t idx_size; + size_t ent_count; sqfs_meta_writer_t *dm; }; @@ -85,6 +86,7 @@ static void writer_reset(sqfs_dir_writer_t *writer) writer->dir_ref = 0; writer->dir_size = 0; writer->idx_size = 0; + writer->ent_count = 0; } sqfs_dir_writer_t *sqfs_dir_writer_create(sqfs_meta_writer_t *dm) @@ -145,6 +147,7 @@ int sqfs_dir_writer_add_entry(sqfs_dir_writer_t *writer, const char *name, } writer->dir_size += sizeof(ent) + ent->name_len; + writer->ent_count += 1; return 0; } @@ -275,6 +278,53 @@ size_t sqfs_dir_writer_get_index_size(const sqfs_dir_writer_t *writer) return writer->idx_size; } +size_t sqfs_dir_writer_get_entry_count(const sqfs_dir_writer_t *writer) +{ + return writer->ent_count; +} + +sqfs_inode_generic_t +*sqfs_dir_writer_create_inode(const sqfs_dir_writer_t *writer, + size_t hlinks, uint32_t xattr, + uint32_t parent_ino) +{ + sqfs_inode_generic_t *inode; + uint64_t start_block; + uint16_t block_offset; + + inode = calloc(1, sizeof(*inode)); + if (inode == NULL) + return NULL; + + start_block = writer->dir_ref >> 16; + block_offset = writer->dir_ref & 0xFFFF; + + if (xattr != 0xFFFFFFFF || start_block > 0xFFFFFFFFUL || + writer->dir_size > 0xFFFF) { + inode->base.type = SQFS_INODE_EXT_DIR; + } else { + inode->base.type = SQFS_INODE_DIR; + } + + if (inode->base.type == SQFS_INODE_DIR) { + inode->data.dir.start_block = start_block; + inode->data.dir.nlink = writer->ent_count + hlinks + 2; + inode->data.dir.size = writer->dir_size; + inode->data.dir.offset = block_offset; + inode->data.dir.parent_inode = parent_ino; + } else { + inode->data.dir_ext.nlink = writer->ent_count + hlinks + 2; + inode->data.dir_ext.size = writer->dir_size; + inode->data.dir_ext.start_block = start_block; + inode->data.dir_ext.parent_inode = parent_ino; + inode->data.dir_ext.offset = block_offset; + inode->data.dir_ext.xattr_idx = xattr; + inode->data.dir_ext.inodex_count = writer->idx_size; + } + + return inode; +} + int sqfs_dir_writer_write_index(const sqfs_dir_writer_t *writer, sqfs_meta_writer_t *im) { diff --git a/lib/sqfshelper/serialize_fstree.c b/lib/sqfshelper/serialize_fstree.c index 78f7d13..61f9ae2 100644 --- a/lib/sqfshelper/serialize_fstree.c +++ b/lib/sqfshelper/serialize_fstree.c @@ -14,31 +14,51 @@ #include #include -static int write_dir_entries(sqfs_dir_writer_t *dirw, tree_node_t *node) +static sqfs_inode_generic_t *write_dir_entries(sqfs_dir_writer_t *dirw, + tree_node_t *node, + sqfs_id_table_t *idtbl) { + uint32_t xattr, parent_inode; + sqfs_inode_generic_t *inode; tree_node_t *it; - uint64_t ref; int ret; if (sqfs_dir_writer_begin(dirw)) - return -1; + return NULL; for (it = node->data.dir->children; it != NULL; it = it->next) { ret = sqfs_dir_writer_add_entry(dirw, it->name, it->inode_num, it->inode_ref, it->mode); if (ret) - return -1; + return NULL; } if (sqfs_dir_writer_end(dirw)) - return -1; + return NULL; + + xattr = (node->xattr == NULL) ? 0xFFFFFFFF : node->xattr->index; + parent_inode = (node->parent == NULL) ? 1 : node->parent->inode_num; + + inode = sqfs_dir_writer_create_inode(dirw, 0, xattr, parent_inode); + if (inode == NULL) { + perror("creating inode"); + return NULL; + } - ref = sqfs_dir_writer_get_dir_reference(dirw); + if (sqfs_id_table_id_to_index(idtbl, node->uid, &inode->base.uid_idx)) + goto fail_id; - node->data.dir->size = sqfs_dir_writer_get_size(dirw); - node->data.dir->start_block = ref >> 16; - node->data.dir->block_offset = ref & 0xFFFF; - return 0; + if (sqfs_id_table_id_to_index(idtbl, node->gid, &inode->base.gid_idx)) + goto fail_id; + + inode->base.mode = node->mode; + inode->base.mod_time = node->mod_time; + inode->base.inode_number = node->inode_num; + return inode; +fail_id: + fputs("failed to allocate IDs\n", stderr); + free(inode); + return NULL; } int sqfs_serialize_fstree(sqfs_file_t *file, sqfs_super_t *super, fstree_t *fs, @@ -69,19 +89,16 @@ int sqfs_serialize_fstree(sqfs_file_t *file, sqfs_super_t *super, fstree_t *fs, for (i = 2; i < fs->inode_tbl_size; ++i) { if (S_ISDIR(fs->inode_table[i]->mode)) { - if (write_dir_entries(dirwr, fs->inode_table[i])) - goto out; + inode = write_dir_entries(dirwr, fs->inode_table[i], + idtbl); + } else { + inode = tree_node_to_inode(fs, idtbl, + fs->inode_table[i]); } - inode = tree_node_to_inode(fs, idtbl, fs->inode_table[i]); if (inode == NULL) goto out; - if (inode->base.type == SQFS_INODE_EXT_DIR) { - inode->data.dir_ext.inodex_count = - sqfs_dir_writer_get_index_size(dirwr); - } - sqfs_meta_writer_get_position(im, &block, &offset); fs->inode_table[i]->inode_ref = (block << 16) | offset; -- cgit v1.2.3