Add helper function to directory writer to create a basic inode

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

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.
@@ -257,9 +257,24 @@ 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 <stdlib.h>
 #include <stdio.h>
 
-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;