X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=osl.c;fp=osl.c;h=0000000000000000000000000000000000000000;hb=b2e6a24448a9e49e0766ab4f32163580eeff469e;hp=e2c1ef46f40624adddf6dd7611e07ec2a9f97ef8;hpb=09b7971c7a862924d4ce669f8a33bda567ba570b;p=paraslash.git

diff --git a/osl.c b/osl.c
deleted file mode 100644
index e2c1ef46..00000000
--- a/osl.c
+++ /dev/null
@@ -1,2082 +0,0 @@
-/*
- * Copyright (C) 2007-2009 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
-
-/** \file osl.c Object storage layer functions. */
-#include <dirent.h> /* readdir() */
-#include <assert.h>
-
-
-#include "para.h"
-#include "error.h"
-#include "fd.h"
-#include "osl_core.h"
-/**
- * A wrapper for lseek(2).
- *
- * \param fd The file descriptor whose offset is to be to repositioned.
- * \param offset A value-result parameter.
- * \param whence Usual repositioning directive.
- *
- * Reposition the offset of the file descriptor \a fd to the argument \a offset
- * according to the directive \a whence. Upon successful return, \a offset
- * contains the resulting offset location as measured in bytes from the
- * beginning of the file.
- *
- * \return Positive on success. Otherwise, the function returns \p -E_LSEEK.
- *
- * \sa lseek(2).
- */
-int para_lseek(int fd, off_t *offset, int whence)
-{
-	int ret = -E_LSEEK;
-
-	*offset = lseek(fd, *offset, whence);
-	if (*offset == -1)
-		return ret;
-	return 1;
-}
-
-/**
- * Wrapper for the write system call.
- *
- * \param fd The file descriptor to write to.
- * \param buf The buffer to write.
- * \param size The length of \a buf in bytes.
- *
- * This function writes out the given buffer and retries if an interrupt
- * occurred during the write.
- *
- * \return On success, the number of bytes written is returned, otherwise, the
- * function returns \p -E_WRITE.
- *
- * \sa write(2).
- */
-ssize_t para_write(int fd, const void *buf, size_t size)
-{
-	ssize_t ret;
-
-	for (;;) {
-		ret = write(fd, buf, size);
-		if ((ret < 0) && (errno == EAGAIN || errno == EINTR))
-			continue;
-		return ret >= 0? ret : -E_WRITE;
-	}
-}
-
-/**
- * Write the whole buffer to a file descriptor.
- *
- * \param fd The file descriptor to write to.
- * \param buf The buffer to write.
- * \param size The length of \a buf in bytes.
- *
- * This function writes the given buffer and continues on short writes and
- * when interrupted by a signal.
- *
- * \return Positive on success, negative on errors. Possible errors: any
- * errors returned by para_write().
- *
- * \sa para_write().
- */
-ssize_t para_write_all(int fd, const void *buf, size_t size)
-{
-//	PARA_DEBUG_LOG("writing %zu bytes\n", size);
-	const char *b = buf;
-	while (size) {
-		ssize_t ret = para_write(fd, b, size);
-//		PARA_DEBUG_LOG("ret: %zd\n", ret);
-		if (ret < 0)
-			return ret;
-		b += ret;
-		size -= ret;
-	}
-	return 1;
-}
-/**
- * Open a file, write the given buffer and close the file.
- *
- * \param filename Full path to the file to open.
- * \param buf The buffer to write to the file.
- * \param size The size of \a buf.
- *
- * \return Positive on success, negative on errors. Possible errors include:
- * any errors from para_open() or para_write().
- *
- * \sa para_open(), para_write().
- */
-int para_write_file(const char *filename, const void *buf, size_t size)
-{
-	int ret, fd;
-
-	ret = para_open(filename, O_WRONLY | O_CREAT | O_EXCL, 0644);
-	if (ret < 0)
-		return ret;
-	fd = ret;
-	ret = para_write_all(fd, buf, size);
-	if (ret < 0)
-		goto out;
-	ret = 1;
-out:
-	close(fd);
-	return ret;
-}
-
-static int append_file(const char *filename, char *header, size_t header_size,
-	char *data, size_t data_size, uint32_t *new_pos)
-{
-	int ret, fd;
-
-//	PARA_DEBUG_LOG("appending %zu  + %zu bytes\n", header_size, data_size);
-	ret = para_open(filename, O_WRONLY | O_CREAT | O_APPEND, 0644);
-	if (ret < 0)
-		return ret;
-	fd = ret;
-	if (header && header_size) {
-		ret = para_write_all(fd, header, header_size);
-		if (ret < 0)
-			goto out;
-	}
-	ret = para_write_all(fd, data, data_size);
-	if (ret < 0)
-		goto out;
-	if (new_pos) {
-		off_t offset = 0;
-		ret = para_lseek(fd, &offset, SEEK_END);
-		if (ret < 0)
-			goto out;
-//		PARA_DEBUG_LOG("new file size: " FMT_OFF_T "\n", offset);
-		*new_pos = offset;
-	}
-	ret = 1;
-out:
-	close(fd);
-	return ret;
-}
-
-/**
- * Traverse the given directory recursively.
- *
- * \param dirname The directory to traverse.
- * \param func The function to call for each entry.
- * \param private_data Pointer to an arbitrary data structure.
- *
- * For each regular file under \a dirname, the supplied function \a func is
- * called.  The full path of the regular file and the \a private_data pointer
- * are passed to \a func. Directories for which the calling process has no
- * permissions to change to are silently ignored.
- *
- * \return Standard.
- */
-int for_each_file_in_dir(const char *dirname,
-		int (*func)(const char *, void *), void *private_data)
-{
-	DIR *dir;
-	struct dirent *entry;
-	int cwd_fd, ret2, ret = para_opendir(dirname, &dir, &cwd_fd);
-
-	if (ret < 0)
-		return ret == -ERRNO_TO_PARA_ERROR(EACCES)? 1 : ret;
-	/* scan cwd recursively */
-	while ((entry = readdir(dir))) {
-		mode_t m;
-		char *tmp;
-		struct stat s;
-
-		if (!strcmp(entry->d_name, "."))
-			continue;
-		if (!strcmp(entry->d_name, ".."))
-			continue;
-		if (lstat(entry->d_name, &s) == -1)
-			continue;
-		m = s.st_mode;
-		if (!S_ISREG(m) && !S_ISDIR(m))
-			continue;
-		tmp = make_message("%s/%s", dirname, entry->d_name);
-		if (!S_ISDIR(m)) {
-			ret = func(tmp, private_data);
-			free(tmp);
-			if (ret < 0)
-				goto out;
-			continue;
-		}
-		/* directory */
-		ret = for_each_file_in_dir(tmp, func, private_data);
-		free(tmp);
-		if (ret < 0)
-			goto out;
-	}
-	ret = 1;
-out:
-	closedir(dir);
-	ret2 = para_fchdir(cwd_fd);
-	if (ret2 < 0 && ret >= 0)
-		ret = ret2;
-	close(cwd_fd);
-	return ret;
-}
-
-static int verify_name(const char *name)
-{
-	if (!name)
-		return -E_BAD_NAME;
-	if (!*name)
-		return -E_BAD_NAME;
-	if (strchr(name, '/'))
-		return -E_BAD_NAME;
-	if (!strcmp(name, ".."))
-		return -E_BAD_NAME;
-	if (!strcmp(name, "."))
-		return -E_BAD_NAME;
-	return 1;
-}
-
-/**
- * Compare two osl objects pointing to unsigned integers of 32 bit size.
- *
- * \param obj1 Pointer to the first integer.
- * \param obj2 Pointer to the second integer.
- *
- * \return The values required for an osl compare function.
- *
- * \sa osl_compare_func, osl_hash_compare().
- */
-int uint32_compare(const struct osl_object *obj1, const struct osl_object *obj2)
-{
-	uint32_t d1 = read_u32((const char *)obj1->data);
-	uint32_t d2 = read_u32((const char *)obj2->data);
-
-	if (d1 < d2)
-		return 1;
-	if (d1 > d2)
-		return -1;
-	return 0;
-}
-
-/**
- * Compare two osl objects pointing to hash values.
- *
- * \param obj1 Pointer to the first hash object.
- * \param obj2 Pointer to the second hash object.
- *
- * \return The values required for an osl compare function.
- *
- * \sa osl_compare_func, uint32_compare().
- */
-int osl_hash_compare(const struct osl_object *obj1, const struct osl_object *obj2)
-{
-	return hash_compare((HASH_TYPE *)obj1->data, (HASH_TYPE *)obj2->data);
-}
-
-static char *disk_storage_dirname(const struct osl_table *t, unsigned col_num,
-		const char *ds_name)
-{
-	char *dirname, *column_name = column_filename(t, col_num);
-
-	if (!(t->desc->flags & OSL_LARGE_TABLE))
-		return column_name;
-	dirname = make_message("%s/%.2s", column_name, ds_name);
-	free(column_name);
-	return dirname;
-}
-
-static char *disk_storage_name_of_object(const struct osl_table *t,
-	const struct osl_object *obj)
-{
-	HASH_TYPE hash[HASH_SIZE];
-	hash_object(obj, hash);
-	return disk_storage_name_of_hash(t, hash);
-}
-
-static int disk_storage_name_of_row(const struct osl_table *t,
-		const struct osl_row *row, char **name)
-{
-	struct osl_object obj;
-	int ret = osl_get_object(t, row, t->disk_storage_name_column, &obj);
-
-	if (ret < 0)
-		return ret;
-	*name = disk_storage_name_of_object(t, &obj);
-	return 1;
-}
-
-static void column_name_hash(const char *col_name, HASH_TYPE *hash)
-{
-	hash_function(col_name, strlen(col_name), hash);
-}
-
-static int init_column_descriptions(struct osl_table *t)
-{
-	int i, j, ret;
-	const struct osl_column_description *cd;
-
-	ret = verify_name(t->desc->name);
-	if (ret < 0)
-		goto err;
-	ret = -E_BAD_DB_DIR;
-	if (!t->desc->dir && (t->num_disk_storage_columns || t->num_mapped_columns))
-		goto err;
-	/* the size of the index header without column descriptions */
-	t->index_header_size = IDX_COLUMN_DESCRIPTIONS;
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		struct osl_column *col = t->columns + i;
-		if (cd->storage_flags & OSL_RBTREE) {
-			if (!cd->compare_function)
-				return -E_NO_COMPARE_FUNC;
-		}
-		if (cd->storage_type == OSL_NO_STORAGE)
-			continue;
-		ret = -E_NO_COLUMN_NAME;
-		if (!cd->name || !cd->name[0])
-			goto err;
-		ret = verify_name(cd->name);
-		if (ret < 0)
-			goto err;
-		t->index_header_size += index_column_description_size(cd->name);
-		column_name_hash(cd->name, col->name_hash);
-		ret = -E_DUPLICATE_COL_NAME;
-		for (j = i + 1; j < t->desc->num_columns; j++) {
-			const char *name2 = get_column_description(t->desc,
-				j)->name;
-			if (cd->name && name2 && !strcmp(cd->name, name2))
-				goto err;
-		}
-	}
-	return 1;
-err:
-	return ret;
-}
-
-/**
- * Initialize a struct table from given table description.
- *
- * \param desc The description of the osl table.
- * \param table_ptr Result is returned here.
- *
- * This function performs several sanity checks on \p desc and returns if any
- * of these tests fail. On success, a struct \p osl_table is allocated and
- * initialized with data derived from \p desc.
- *
- * \return Positive on success, negative on errors. Possible errors include: \p
- * E_BAD_TABLE_DESC, \p E_NO_COLUMN_DESC, \p E_NO_COLUMNS, \p
- * E_BAD_STORAGE_TYPE, \p E_BAD_STORAGE_FLAGS, \p E_BAD_STORAGE_SIZE, \p
- * E_NO_UNIQUE_RBTREE_COLUMN, \p E_NO_RBTREE_COL.
- *
- * \sa struct osl_table.
- */
-int init_table_structure(const struct osl_table_description *desc,
-		struct osl_table **table_ptr)
-{
-	const struct osl_column_description *cd;
-	struct osl_table *t = para_calloc(sizeof(*t));
-	int i, ret = -E_BAD_TABLE_DESC, have_disk_storage_name_column = 0;
-
-	if (!desc)
-		goto err;
-	PARA_DEBUG_LOG("creating table structure for '%s' from table "
-		"description\n", desc->name);
-	ret = -E_NO_COLUMN_DESC;
-	if (!desc->column_descriptions)
-		goto err;
-	ret = -E_NO_COLUMNS;
-	if (!desc->num_columns)
-		goto err;
-	t->columns = para_calloc(desc->num_columns * sizeof(struct osl_column));
-	t->desc = desc;
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		enum osl_storage_type st = cd->storage_type;
-		enum osl_storage_flags sf = cd->storage_flags;
-		struct osl_column *col = &t->columns[i];
-
-		ret = -E_BAD_STORAGE_TYPE;
-		if (st != OSL_MAPPED_STORAGE && st != OSL_DISK_STORAGE
-				&& st != OSL_NO_STORAGE)
-			goto err;
-		ret = -E_BAD_STORAGE_FLAGS;
-		if (st == OSL_DISK_STORAGE && sf & OSL_RBTREE)
-			goto err;
-		ret = -E_BAD_STORAGE_SIZE;
-		if (sf & OSL_FIXED_SIZE && !cd->data_size)
-			goto err;
-		switch (st) {
-		case OSL_DISK_STORAGE:
-			t->num_disk_storage_columns++;
-			break;
-		case OSL_MAPPED_STORAGE:
-			t->num_mapped_columns++;
-			col->index_offset = t->row_index_size;
-			t->row_index_size += 8;
-			break;
-		case OSL_NO_STORAGE:
-			col->volatile_num = t->num_volatile_columns;
-			t->num_volatile_columns++;
-			break;
-		}
-		if (sf & OSL_RBTREE) {
-			col->rbtree_num = t->num_rbtrees;
-			t->num_rbtrees++;
-			if ((sf & OSL_UNIQUE) && (st == OSL_MAPPED_STORAGE)) {
-				if (!have_disk_storage_name_column)
-					t->disk_storage_name_column = i;
-				have_disk_storage_name_column = 1;
-			}
-		}
-	}
-	ret = -E_NO_UNIQUE_RBTREE_COLUMN;
-	if (t->num_disk_storage_columns && !have_disk_storage_name_column)
-		goto err;
-	ret = -E_NO_RBTREE_COL;
-	if (!t->num_rbtrees)
-		goto err;
-	/* success */
-	PARA_DEBUG_LOG("OK. Index entry size: %u\n", t->row_index_size);
-	ret = init_column_descriptions(t);
-	if (ret < 0)
-		goto err;
-	*table_ptr = t;
-	return 1;
-err:
-	free(t->columns);
-	free(t);
-	return ret;
-}
-
-/**
- * Read the table description from index header.
- *
- * \param map The memory mapping of the index file.
- * \param desc The values found in the index header are returned here.
- *
- * Read the index header, check for the paraslash magic string and the table version number.
- * Read all information stored in the index header into \a desc.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa struct osl_table_description, osl_create_table.
- */
-int read_table_desc(struct osl_object *map, struct osl_table_description *desc)
-{
-	char *buf = map->data;
-	uint8_t version;
-	uint16_t header_size;
-	int ret, i;
-	unsigned offset;
-	struct osl_column_description *cd;
-
-	if (map->size < MIN_INDEX_HEADER_SIZE(1))
-		return -E_SHORT_TABLE;
-	if (strncmp(buf + IDX_PARA_MAGIC, PARA_MAGIC, strlen(PARA_MAGIC)))
-		return -E_NO_MAGIC;
-	version = read_u8(buf + IDX_VERSION);
-	if (version < MIN_TABLE_VERSION || version > MAX_TABLE_VERSION)
-		return -E_VERSION_MISMATCH;
-	desc->num_columns = read_u8(buf + IDX_TABLE_FLAGS);
-	desc->flags = read_u8(buf + IDX_TABLE_FLAGS);
-	desc->num_columns = read_u16(buf + IDX_NUM_COLUMNS);
-	PARA_DEBUG_LOG("%u columns\n", desc->num_columns);
-	if (!desc->num_columns)
-		return -E_NO_COLUMNS;
-	header_size = read_u16(buf + IDX_HEADER_SIZE);
-	if (map->size < header_size)
-		return -E_BAD_SIZE;
-	desc->column_descriptions = para_calloc(desc->num_columns
-		* sizeof(struct osl_column_description));
-	offset = IDX_COLUMN_DESCRIPTIONS;
-	FOR_EACH_COLUMN(i, desc, cd) {
-		char *null_byte;
-
-		ret = -E_SHORT_TABLE;
-		if (map->size < offset + MIN_IDX_COLUMN_DESCRIPTION_SIZE) {
-			PARA_ERROR_LOG("map size = %zu < %u = offset + min desc size\n",
-				map->size, offset + MIN_IDX_COLUMN_DESCRIPTION_SIZE);
-			goto err;
-		}
-		cd->storage_type = read_u16(buf + offset + IDX_CD_STORAGE_TYPE);
-		cd->storage_flags = read_u16(buf + offset +
-			IDX_CD_STORAGE_FLAGS);
-		cd->data_size = read_u32(buf + offset + IDX_CD_DATA_SIZE);
-		null_byte = memchr(buf + offset + IDX_CD_NAME, '\0',
-			map->size - offset - IDX_CD_NAME);
-		ret = -E_INDEX_CORRUPTION;
-		if (!null_byte)
-			goto err;
-		cd->name = para_strdup(buf + offset + IDX_CD_NAME);
-		offset += index_column_description_size(cd->name);
-	}
-	if (offset != header_size) {
-		ret = -E_INDEX_CORRUPTION;
-		PARA_ERROR_LOG("real header size = %u != %u = stored header size\n",
-			offset, header_size);
-		goto err;
-	}
-	return 1;
-err:
-	FOR_EACH_COLUMN(i, desc, cd)
-		free(cd->name);
-	return ret;
-}
-
-/*
- * check whether the table description given by \p t->desc matches the on-disk
- * table structure stored in the index of \a t.
- */
-static int compare_table_descriptions(struct osl_table *t)
-{
-	int i, ret;
-	struct osl_table_description desc;
-	const struct osl_column_description *cd1, *cd2;
-
-	/* read the on-disk structure into desc */
-	ret = read_table_desc(&t->index_map, &desc);
-	if (ret < 0)
-		return ret;
-	ret = -E_BAD_TABLE_FLAGS;
-	if (desc.flags != t->desc->flags)
-		goto out;
-	ret = -E_BAD_COLUMN_NUM;
-	if (desc.num_columns != t->desc->num_columns)
-		goto out;
-	FOR_EACH_COLUMN(i, t->desc, cd1) {
-		cd2 = get_column_description(&desc, i);
-		ret = -E_BAD_STORAGE_TYPE;
-		if (cd1->storage_type != cd2->storage_type)
-			goto out;
-		ret = -E_BAD_STORAGE_FLAGS;
-		if (cd1->storage_flags != cd2->storage_flags) {
-			PARA_ERROR_LOG("sf1 = %u != %u = sf2\n",
-				cd1->storage_flags, cd2->storage_flags);
-			goto out;
-		}
-		ret = -E_BAD_DATA_SIZE;
-		if (cd1->storage_flags & OSL_FIXED_SIZE)
-			if (cd1->data_size != cd2->data_size)
-				goto out;
-		ret = -E_BAD_COLUMN_NAME;
-		if (strcmp(cd1->name, cd2->name))
-			goto out;
-	}
-	PARA_DEBUG_LOG("table description of '%s' matches on-disk data, good\n",
-		t->desc->name);
-	ret = 1;
-out:
-	FOR_EACH_COLUMN(i, &desc, cd1)
-		free(cd1->name);
-	free(desc.column_descriptions);
-	return ret;
-}
-
-static int create_table_index(struct osl_table *t)
-{
-	char *buf, *filename;
-	int i, ret;
-	size_t size = t->index_header_size;
-	const struct osl_column_description *cd;
-	unsigned offset;
-
-	PARA_INFO_LOG("creating %zu byte index for table %s\n", size,
-		t->desc->name);
-	buf = para_calloc(size);
-	sprintf(buf + IDX_PARA_MAGIC, "%s", PARA_MAGIC);
-	write_u8(buf + IDX_TABLE_FLAGS, t->desc->flags);
-	write_u8(buf + IDX_DIRTY_FLAG, 0);
-	write_u8(buf + IDX_VERSION, CURRENT_TABLE_VERSION);
-	write_u16(buf + IDX_NUM_COLUMNS, t->desc->num_columns);
-	write_u16(buf + IDX_HEADER_SIZE, t->index_header_size);
-	offset = IDX_COLUMN_DESCRIPTIONS;
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		write_u16(buf + offset + IDX_CD_STORAGE_TYPE,
-			cd->storage_type);
-		write_u16(buf + offset + IDX_CD_STORAGE_FLAGS,
-			cd->storage_flags);
-		if (cd->storage_flags & OSL_FIXED_SIZE)
-			write_u32(buf + offset + IDX_CD_DATA_SIZE,
-				cd->data_size);
-		strcpy(buf + offset + IDX_CD_NAME, cd->name);
-		offset += index_column_description_size(cd->name);
-	}
-	assert(offset = size);
-	filename = index_filename(t->desc);
-	ret = para_write_file(filename, buf, size);
-	free(buf);
-	free(filename);
-	return ret;
-}
-
-/**
- * Create a new osl table.
- *
- * \param desc Pointer to the table description.
- *
- * \return Standard.
- */
-int osl_create_table(const struct osl_table_description *desc)
-{
-	const struct osl_column_description *cd;
-	char *table_dir = NULL, *filename;
-	struct osl_table *t;
-	int i, ret = init_table_structure(desc, &t);
-
-	if (ret < 0)
-		return ret;
-	PARA_INFO_LOG("creating %s\n", desc->name);
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		if (cd->storage_type == OSL_NO_STORAGE)
-			continue;
-		if (!table_dir) {
-			ret = para_mkdir(desc->dir, 0777);
-			if (ret < 0 && !is_errno(-ret, EEXIST))
-				goto out;
-			table_dir = make_message("%s/%s", desc->dir,
-				desc->name);
-			ret = para_mkdir(table_dir, 0777);
-			if (ret < 0)
-				goto out;
-		}
-		filename = column_filename(t, i);
-		PARA_INFO_LOG("filename: %s\n", filename);
-		if (cd->storage_type == OSL_MAPPED_STORAGE) {
-			ret = para_open(filename, O_RDWR | O_CREAT | O_EXCL,
-				0644);
-			free(filename);
-			if (ret < 0)
-				goto out;
-			close(ret);
-			continue;
-		}
-		/* DISK STORAGE */
-		ret = para_mkdir(filename, 0777);
-		free(filename);
-		if (ret < 0)
-			goto out;
-	}
-	if (t->num_mapped_columns) {
-		ret = create_table_index(t);
-		if (ret < 0)
-			goto out;
-	}
-	ret = 1;
-out:
-	free(table_dir);
-	free(t->columns);
-	free(t);
-	return ret;
-}
-
-static int table_is_dirty(struct osl_table *t)
-{
-	char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
-	uint8_t dirty = read_u8(buf) & 0x1;
-	return !!dirty;
-}
-
-static void mark_table_dirty(struct osl_table *t)
-{
-	char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
-	write_u8(buf, read_u8(buf) | 1);
-}
-
-static void mark_table_clean(struct osl_table *t)
-{
-	char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
-	write_u8(buf, read_u8(buf) & 0xfe);
-}
-
-static void unmap_column(struct osl_table *t, unsigned col_num)
-{
-	struct osl_object map = t->columns[col_num].data_map;
-	int ret;
-	if (!map.data)
-		return;
-	ret = para_munmap(map.data, map.size);
-	assert(ret > 0);
-	map.data = NULL;
-}
-
-/**
- * Unmap all mapped files of an osl table.
- *
- * \param t Pointer to a mapped table.
- * \param flags Options for unmapping.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa map_table(), enum osl_close_flags, para_munmap().
- */
-int unmap_table(struct osl_table *t, enum osl_close_flags flags)
-{
-	unsigned i;
-	const struct osl_column_description *cd;
-	int ret;
-
-	if (!t->num_mapped_columns) /* can this ever happen? */
-		return 1;
-	PARA_DEBUG_LOG("unmapping table '%s'\n", t->desc->name);
-	if (!t->index_map.data)
-		return -E_NOT_MAPPED;
-	if (flags & OSL_MARK_CLEAN)
-		mark_table_clean(t);
-	ret = para_munmap(t->index_map.data, t->index_map.size);
-	if (ret < 0)
-		return ret;
-	t->index_map.data = NULL;
-	if (!t->num_rows)
-		return 1;
-	FOR_EACH_MAPPED_COLUMN(i, t, cd)
-		unmap_column(t, i);
-	return 1;
-}
-
-static int map_column(struct osl_table *t, unsigned col_num)
-{
-	struct stat statbuf;
-	char *filename = column_filename(t, col_num);
-	int ret = -E_STAT;
-	if (stat(filename, &statbuf) < 0) {
-		free(filename);
-		return ret;
-	}
-	if (!(S_IFREG & statbuf.st_mode)) {
-		free(filename);
-		return ret;
-	}
-	ret = mmap_full_file(filename, O_RDWR,
-		&t->columns[col_num].data_map.data,
-		&t->columns[col_num].data_map.size,
-		NULL);
-	free(filename);
-	return ret;
-}
-
-/**
- * Map the index file and all columns of type \p OSL_MAPPED_STORAGE into memory.
- *
- * \param t Pointer to an initialized table structure.
- * \param flags Mapping options.
- *
- * \return Negative return value on errors; on success the number of rows
- * (including invalid rows) is returned.
- *
- * \sa unmap_table(), enum map_table_flags, osl_open_table(), mmap(2).
- */
-int map_table(struct osl_table *t, enum map_table_flags flags)
-{
-	char *filename;
-	const struct osl_column_description *cd;
-	int i = 0, ret, num_rows = 0;
-
-	if (!t->num_mapped_columns)
-		return 0;
-	if (t->index_map.data)
-		return -E_ALREADY_MAPPED;
-	filename = index_filename(t->desc);
-	PARA_DEBUG_LOG("mapping table '%s' (index: %s)\n", t->desc->name, filename);
-	ret = mmap_full_file(filename, flags & MAP_TBL_FL_MAP_RDONLY?
-		O_RDONLY : O_RDWR, &t->index_map.data, &t->index_map.size, NULL);
-	free(filename);
-	if (ret < 0)
-		return ret;
-	if (flags & MAP_TBL_FL_VERIFY_INDEX) {
-		ret = compare_table_descriptions(t);
-		if (ret < 0)
-			goto err;
-	}
-	ret = -E_BUSY;
-	if (!(flags & MAP_TBL_FL_IGNORE_DIRTY)) {
-		if (table_is_dirty(t)) {
-			PARA_ERROR_LOG("%s is dirty\n", t->desc->name);
-			goto err;
-		}
-	}
-	mark_table_dirty(t);
-	num_rows = table_num_rows(t);
-	if (!num_rows)
-		return num_rows;
-	/* map data files */
-	FOR_EACH_MAPPED_COLUMN(i, t, cd) {
-		ret = map_column(t, i);
-		if (ret < 0)
-			goto err;
-	}
-	return num_rows;
-err:	/* unmap what is already mapped */
-	for (i--; i >= 0; i--) {
-		struct osl_object map = t->columns[i].data_map;
-		para_munmap(map.data, map.size);
-		map.data = NULL;
-	}
-	para_munmap(t->index_map.data, t->index_map.size);
-	t->index_map.data = NULL;
-	return ret;
-}
-
-/**
- * Retrieve a mapped object by row and column number.
- *
- * \param t Pointer to an open osl table.
- * \param col_num Number of the mapped column containing the object to retrieve.
- * \param row_num Number of the row containing the object to retrieve.
- * \param obj The result is returned here.
- *
- * It is considered an error if \a col_num does not refer to a column
- * of storage type \p OSL_MAPPED_STORAGE.
- *
- * \return Positive on success, negative on errors. Possible errors include:
- * \p E_BAD_ROW_NUM, \p E_INVALID_OBJECT.
- *
- * \sa osl_storage_type.
- */
-int get_mapped_object(const struct osl_table *t, unsigned col_num,
-	uint32_t row_num, struct osl_object *obj)
-{
-	struct osl_column *col = &t->columns[col_num];
-	uint32_t offset;
-	char *header;
-	char *cell_index;
-	int ret;
-
-	if (t->num_rows <= row_num)
-		return -E_BAD_ROW_NUM;
-	ret = get_cell_index(t, row_num, col_num, &cell_index);
-	if (ret < 0)
-		return ret;
-	offset = read_u32(cell_index);
-	obj->size = read_u32(cell_index + 4) - 1;
-	header = col->data_map.data + offset;
-	obj->data = header + 1;
-	if (read_u8(header) == 0xff) {
-		PARA_ERROR_LOG("col %u, size %zu, offset %u\n", col_num,
-			obj->size, offset);
-		return -E_INVALID_OBJECT;
-	}
-	return 1;
-}
-
-static int search_rbtree(const struct osl_object *obj,
-		const struct osl_table *t, unsigned col_num,
-		struct rb_node **result, struct rb_node ***rb_link)
-{
-	struct osl_column *col = &t->columns[col_num];
-	struct rb_node **new = &col->rbtree.rb_node, *parent = NULL;
-	const struct osl_column_description *cd =
-		get_column_description(t->desc, col_num);
-	enum osl_storage_type st = cd->storage_type;
-	while (*new) {
-		struct osl_row *this_row = get_row_pointer(*new,
-			col->rbtree_num);
-		int ret;
-		struct osl_object this_obj;
-		parent = *new;
-		if (st == OSL_MAPPED_STORAGE) {
-			ret = get_mapped_object(t, col_num, this_row->num,
-				&this_obj);
-			if (ret < 0)
-				return ret;
-		} else
-			this_obj = this_row->volatile_objects[col->volatile_num];
-		ret = cd->compare_function(obj, &this_obj);
-		if (!ret) {
-			if (result)
-				*result = get_rb_node_pointer(this_row,
-					col->rbtree_num);
-			return 1;
-		}
-		if (ret < 0)
-			new = &((*new)->rb_left);
-		else
-			new = &((*new)->rb_right);
-	}
-	if (result)
-		*result = parent;
-	if (rb_link)
-		*rb_link = new;
-	return -E_RB_KEY_NOT_FOUND;
-}
-
-static int insert_rbtree(struct osl_table *t, unsigned col_num,
-	const struct osl_row *row, const struct osl_object *obj)
-{
-	struct rb_node *parent, **rb_link;
-	unsigned rbtree_num;
-	struct rb_node *n;
-	int ret = search_rbtree(obj, t, col_num, &parent, &rb_link);
-
-	if (ret > 0)
-		return -E_RB_KEY_EXISTS;
-	rbtree_num = t->columns[col_num].rbtree_num;
-	n = get_rb_node_pointer(row, rbtree_num);
-	rb_link_node(n, parent, rb_link);
-	rb_insert_color(n, &t->columns[col_num].rbtree);
-	return 1;
-}
-
-static void remove_rb_node(struct osl_table *t, unsigned col_num,
-		const struct osl_row *row)
-{
-	struct osl_column *col = &t->columns[col_num];
-	const struct osl_column_description *cd =
-		get_column_description(t->desc, col_num);
-	enum osl_storage_flags sf = cd->storage_flags;
-	struct rb_node *victim, *splice_out_node, *tmp;
-	if (!(sf & OSL_RBTREE))
-		return;
-	/*
-	 * Which node is removed/spliced out actually depends on how many
-	 * children the victim node has: If it has no children, it gets
-	 * deleted. If it has one child, it gets spliced out. If it has two
-	 * children, its successor (which has at most a right child) gets
-	 * spliced out.
-	 */
-	victim = get_rb_node_pointer(row, col->rbtree_num);
-	if (victim->rb_left && victim->rb_right)
-		splice_out_node = rb_next(victim);
-	else
-		splice_out_node = victim;
-	/* Go up to the root and decrement the size of each node in the path. */
-	for (tmp = splice_out_node; tmp; tmp = rb_parent(tmp))
-		tmp->size--;
-	rb_erase(victim, &col->rbtree);
-}
-
-static int add_row_to_rbtrees(struct osl_table *t, uint32_t row_num,
-		struct osl_object *volatile_objs, struct osl_row **row_ptr)
-{
-	unsigned i;
-	int ret;
-	struct osl_row *row = allocate_row(t->num_rbtrees);
-	const struct osl_column_description *cd;
-
-	row->num = row_num;
-	row->volatile_objects = volatile_objs;
-	FOR_EACH_RBTREE_COLUMN(i, t, cd) {
-		if (cd->storage_type == OSL_MAPPED_STORAGE) {
-			struct osl_object obj;
-			ret = get_mapped_object(t, i, row_num, &obj);
-			if (ret < 0)
-				goto err;
-			ret = insert_rbtree(t, i, row, &obj);
-		} else { /* volatile */
-			const struct osl_object *obj
-				= volatile_objs + t->columns[i].volatile_num;
-			ret = insert_rbtree(t, i, row, obj);
-		}
-		if (ret < 0)
-			goto err;
-	}
-	if (row_ptr)
-		*row_ptr = row;
-	return 1;
-err: /* rollback changes, i.e. remove added entries from rbtrees */
-	while (i)
-		remove_rb_node(t, i--, row);
-	free(row);
-	return ret;
-}
-
-static void free_volatile_objects(const struct osl_table *t,
-		enum osl_close_flags flags)
-{
-	int i, j;
-	struct rb_node *n;
-	struct osl_column *rb_col;
-	const struct osl_column_description *cd;
-
-	if (!t->num_volatile_columns)
-		return;
-	/* find the first rbtree column (any will do) */
-	FOR_EACH_RBTREE_COLUMN(i, t, cd)
-		break;
-	rb_col = t->columns + i;
-	/* walk that rbtree and free all volatile objects */
-	for (n = rb_first(&rb_col->rbtree); n; n = rb_next(n)) {
-		struct osl_row *r = get_row_pointer(n, rb_col->rbtree_num);
-		if (flags & OSL_FREE_VOLATILE)
-			FOR_EACH_VOLATILE_COLUMN(j, t, cd) {
-				if (cd->storage_flags & OSL_DONT_FREE)
-					continue;
-				free(r->volatile_objects[
-					t->columns[j].volatile_num].data);
-			}
-//			for (j = 0; j < t->num_volatile_columns; j++)
-//				free(r->volatile_objects[j].data);
-		free(r->volatile_objects);
-	}
-}
-
-/**
- * Erase all rbtree nodes and free resources.
- *
- * \param t Pointer to an open osl table.
- *
- * This function is called by osl_close_table().
- */
-void clear_rbtrees(struct osl_table *t)
-{
-	const struct osl_column_description *cd;
-	unsigned i, rbtrees_cleared = 0;
-
-	FOR_EACH_RBTREE_COLUMN(i, t, cd) {
-		struct osl_column *col = &t->columns[i];
-		struct rb_node *n;
-		rbtrees_cleared++;
-		for (n = rb_first(&col->rbtree); n;) {
-			struct osl_row *r;
-			rb_erase(n, &col->rbtree);
-			if (rbtrees_cleared == t->num_rbtrees) {
-				r = get_row_pointer(n, col->rbtree_num);
-				n = rb_next(n);
-				free(r);
-			} else
-				n = rb_next(n);
-		}
-	}
-
-}
-
-/**
- * Close an osl table.
- *
- * \param t Pointer to the table to be closed.
- * \param flags Options for what should be cleaned up.
- *
- * If osl_open_table() succeeds, the resulting table pointer must later be
- * passed to this function in order to flush all changes to the file system and
- * to free the resources that were allocated by osl_open_table().
- *
- * \return Positive on success, negative on errors. Possible errors: \p E_BAD_TABLE,
- * errors returned by unmap_table().
- *
- * \sa osl_open_table(), unmap_table().
- */
-int osl_close_table(struct osl_table *t, enum osl_close_flags flags)
-{
-	int ret;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	free_volatile_objects(t, flags);
-	clear_rbtrees(t);
-	ret = unmap_table(t, flags);
-	if (ret < 0)
-		PARA_ERROR_LOG("unmap_table failed: %d\n", ret);
-	free(t->columns);
-	free(t);
-	return ret;
-}
-
-/**
- * Find out whether the given row number corresponds to an invalid row.
- *
- * \param t Pointer to the osl table.
- * \param row_num The number of the row in question.
- *
- * By definition, a row is considered invalid if all its index entries
- * are invalid.
- *
- * \return Positive if \a row_num corresponds to an invalid row,
- * zero if it corresponds to a valid row, negative on errors.
- */
-int row_is_invalid(struct osl_table *t, uint32_t row_num)
-{
-	char *row_index;
-	int i, ret = get_row_index(t, row_num, &row_index);
-
-	if (ret < 0)
-		return ret;
-	for (i = 0; i < t->row_index_size; i++) {
-		if ((unsigned char)row_index[i] != 0xff)
-			return 0;
-	}
-	PARA_INFO_LOG("row %d is invalid\n", row_num);
-	return 1;
-}
-
-/**
- * Invalidate a row of an osl table.
- *
- * \param t Pointer to an open osl table.
- * \param row_num Number of the row to mark as invalid.
- *
- * This function marks each mapped object in the index entry of \a row as
- * invalid.
- *
- * \return Positive on success, negative on errors.
- */
-int mark_row_invalid(struct osl_table *t, uint32_t row_num)
-{
-	char *row_index;
-	int ret = get_row_index(t, row_num, &row_index);
-
-	if (ret < 0)
-		return ret;
-	PARA_INFO_LOG("marking row %d as invalid\n", row_num);
-	memset(row_index, 0xff, t->row_index_size);
-	return 1;
-}
-
-/**
- * Initialize all rbtrees and compute number of invalid rows.
- *
- * \param t The table containing the rbtrees to be initialized.
- *
- * \return Positive on success, negative on errors.
- */
-int init_rbtrees(struct osl_table *t)
-{
-	int i, ret;
-	const struct osl_column_description *cd;
-
-	/* create rbtrees */
-	FOR_EACH_RBTREE_COLUMN(i, t, cd)
-		t->columns[i].rbtree = RB_ROOT;
-	/* add valid rows to rbtrees */
-	t->num_invalid_rows = 0;
-	for (i = 0; i < t->num_rows; i++) {
-		ret = row_is_invalid(t, i);
-		if (ret < 0)
-			return ret;
-		if (ret) {
-			t->num_invalid_rows++;
-			continue;
-		}
-		ret = add_row_to_rbtrees(t, i, NULL, NULL);
-		if (ret < 0)
-			return ret;
-	}
-	return 1;
-}
-
-/**
- * Open an osl table.
- *
- * Each osl table must be opened before its data can be accessed.
- *
- * \param table_desc Describes the table to be opened.
- * \param result Contains a pointer to the open table on success.
- *
- * The table description given by \a desc should coincide with the
- * description used at creation time.
- *
- * \return Standard.
- */
-int osl_open_table(const struct osl_table_description *table_desc,
-		struct osl_table **result)
-{
-	int i, ret;
-	struct osl_table *t;
-	const struct osl_column_description *cd;
-
-	PARA_INFO_LOG("opening table %s\n", table_desc->name);
-	ret = init_table_structure(table_desc, &t);
-	if (ret < 0)
-		return ret;
-	FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd) {
-		/* check if directory exists */
-		char *dirname = column_filename(t, i);
-		struct stat statbuf;
-		ret = stat(dirname, &statbuf);
-		free(dirname);
-		if (ret < 0) {
-			ret = -ERRNO_TO_PARA_ERROR(errno);
-			goto err;
-		}
-		ret = -ERRNO_TO_PARA_ERROR(ENOTDIR);
-		if (!S_ISDIR(statbuf.st_mode))
-			goto err;
-	}
-	ret = map_table(t, MAP_TBL_FL_VERIFY_INDEX);
-	if (ret < 0)
-		goto err;
-	t->num_rows = ret;
-	PARA_DEBUG_LOG("num rows: %d\n", t->num_rows);
-	ret = init_rbtrees(t);
-	if (ret < 0) {
-		osl_close_table(t, OSL_MARK_CLEAN); /* ignore further errors */
-		return ret;
-	}
-	*result = t;
-	return 1;
-err:
-	free(t->columns);
-	free(t);
-	return ret;
-}
-
-static int create_disk_storage_object_dir(const struct osl_table *t,
-		unsigned col_num, const char *ds_name)
-{
-	char *dirname;
-	int ret;
-
-	if (!(t->desc->flags & OSL_LARGE_TABLE))
-		return 1;
-	dirname = disk_storage_dirname(t, col_num, ds_name);
-	ret = para_mkdir(dirname, 0777);
-	free(dirname);
-	if (ret < 0 && !is_errno(-ret, EEXIST))
-		return ret;
-	return 1;
-}
-
-static int write_disk_storage_file(const struct osl_table *t, unsigned col_num,
-	const struct osl_object *obj, const char *ds_name)
-{
-	int ret;
-	char *filename;
-
-	ret = create_disk_storage_object_dir(t, col_num, ds_name);
-	if (ret < 0)
-		return ret;
-	filename = disk_storage_path(t, col_num, ds_name);
-	ret = para_write_file(filename, obj->data, obj->size);
-	free(filename);
-	return ret;
-}
-
-static int append_map_file(const struct osl_table *t, unsigned col_num,
-	const struct osl_object *obj, uint32_t *new_size)
-{
-	char *filename = column_filename(t, col_num);
-	int ret;
-	char header = 0; /* zero means valid object */
-
-//	PARA_DEBUG_LOG("appending %zu + 1 byte\n", obj->size);
-	ret = append_file(filename, &header, 1, obj->data, obj->size,
-		new_size);
-	free(filename);
-	return ret;
-}
-
-static int append_row_index(const struct osl_table *t, char *row_index)
-{
-	char *filename;
-	int ret;
-
-	if (!t->num_mapped_columns)
-		return 1;
-	filename = index_filename(t->desc);
-	ret = append_file(filename, NULL, 0, row_index,
-		t->row_index_size, NULL);
-	free(filename);
-	return ret;
-}
-
-/**
- * A wrapper for truncate(2)
- *
- * \param path Name of the regular file to truncate
- * \param size Number of bytes to \b shave \b off
- *
- * Truncate the regular file named by \a path by \a size bytes.
- *
- * \return Positive on success, negative on errors. Possible errors include: \p
- * E_STAT, \p E_BAD_SIZE, \p E_TRUNC.
- *
- * \sa truncate(2)
- */
-int para_truncate(const char *path, off_t size)
-{
-	int ret;
-	struct stat statbuf;
-
-	ret = -E_STAT;
-	if (stat(path, &statbuf) < 0)
-		goto out;
-	ret = -E_BAD_SIZE;
-	if (statbuf.st_size < size)
-		goto out;
-	ret = -E_TRUNC;
-	if (truncate(path, statbuf.st_size - size) < 0)
-		goto out;
-	ret = 1;
-out:
-	return ret;
-}
-
-static int truncate_mapped_file(const struct osl_table *t, unsigned col_num,
-		off_t size)
-{
-	char *filename = column_filename(t, col_num);
-	int ret = para_truncate(filename, size);
-	free(filename);
-	return ret;
-}
-
-static int delete_disk_storage_file(const struct osl_table *t, unsigned col_num,
-		const char *ds_name)
-{
-	char *dirname, *filename = disk_storage_path(t, col_num, ds_name);
-	int ret = unlink(filename), err = errno;
-
-	free(filename);
-	if (ret < 0)
-		return -ERRNO_TO_PARA_ERROR(err);
-	if (!(t->desc->flags & OSL_LARGE_TABLE))
-		return 1;
-	dirname = disk_storage_dirname(t, col_num, ds_name);
-	rmdir(dirname);
-	free(dirname);
-	return 1;
-}
-
-/**
- * Add a new row to an osl table and retrieve this row.
- *
- * \param t Pointer to an open osl table.
- * \param objects Array of objects to be added.
- * \param row Result pointer.
- *
- * The \a objects parameter must point to an array containing one object per
- * column.  The order of the objects in the array is given by the table
- * description of \a table. Several sanity checks are performed during object
- * insertion and the function returns without modifying the table if any of
- * these tests fail.  In fact, it is atomic in the sense that it either
- * succeeds or leaves the table unchanged (i.e. either all or none of the
- * objects are added to the table).
- *
- * It is considered an error if an object is added to a column with associated
- * rbtree if this object is equal to an object already contained in that column
- * (i.e. the compare function for the column's rbtree returns zero).
- *
- * Possible errors include: \p E_RB_KEY_EXISTS, \p E_BAD_DATA_SIZE.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa struct osl_table_description, osl_compare_func, osl_add_row().
- */
-int osl_add_and_get_row(struct osl_table *t, struct osl_object *objects,
-		struct osl_row **row)
-{
-	int i, ret;
-	char *ds_name = NULL;
-	struct rb_node **rb_parents = NULL, ***rb_links = NULL;
-	char *new_row_index = NULL;
-	struct osl_object *volatile_objs = NULL;
-	const struct osl_column_description *cd;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	rb_parents = para_malloc(t->num_rbtrees * sizeof(struct rn_node*));
-	rb_links = para_malloc(t->num_rbtrees * sizeof(struct rn_node**));
-	if (t->num_mapped_columns)
-		new_row_index = para_malloc(t->row_index_size);
-	/* pass 1: sanity checks */
-//	PARA_DEBUG_LOG("sanity tests: %p:%p\n", objects[0].data,
-//		objects[1].data);
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		enum osl_storage_type st = cd->storage_type;
-		enum osl_storage_flags sf = cd->storage_flags;
-
-//		ret = -E_NULL_OBJECT;
-//		if (!objects[i])
-//			goto out;
-		if (st == OSL_DISK_STORAGE)
-			continue;
-		if (sf & OSL_RBTREE) {
-			unsigned rbtree_num = t->columns[i].rbtree_num;
-			ret = -E_RB_KEY_EXISTS;
-//			PARA_DEBUG_LOG("checking whether %p exists\n",
-//				objects[i].data);
-			if (search_rbtree(objects + i, t, i,
-					&rb_parents[rbtree_num],
-					&rb_links[rbtree_num]) > 0)
-				goto out;
-		}
-		if (sf & OSL_FIXED_SIZE) {
-//			PARA_DEBUG_LOG("fixed size. need: %zu, have: %d\n",
-//				objects[i].size, cd->data_size);
-			ret = -E_BAD_DATA_SIZE;
-			if (objects[i].size != cd->data_size)
-				goto out;
-		}
-	}
-	if (t->num_disk_storage_columns)
-		ds_name = disk_storage_name_of_object(t,
-			&objects[t->disk_storage_name_column]);
-	ret = unmap_table(t, OSL_MARK_CLEAN);
-	if (ret < 0)
-		goto out;
-//	PARA_DEBUG_LOG("sanity tests passed%s\n", "");
-	/* pass 2: create data files, append map data */
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		enum osl_storage_type st = cd->storage_type;
-		if (st == OSL_NO_STORAGE)
-			continue;
-		if (st == OSL_MAPPED_STORAGE) {
-			uint32_t new_size;
-			struct osl_column *col = &t->columns[i];
-//			PARA_DEBUG_LOG("appending object of size %zu\n",
-//				objects[i].size);
-			ret = append_map_file(t, i, objects + i, &new_size);
-			if (ret < 0)
-				goto rollback;
-			update_cell_index(new_row_index, col, new_size,
-				objects[i].size);
-			continue;
-		}
-		/* DISK_STORAGE */
-		ret = write_disk_storage_file(t, i, objects + i, ds_name);
-		if (ret < 0)
-			goto rollback;
-	}
-	ret = append_row_index(t, new_row_index);
-	if (ret < 0)
-		goto rollback;
-	ret = map_table(t, MAP_TBL_FL_VERIFY_INDEX);
-	if (ret < 0) { /* truncate index and rollback changes */
-		char *filename = index_filename(t->desc);
-		para_truncate(filename, t->row_index_size);
-		free(filename);
-		goto rollback;
-	}
-	/* pass 3: add entry to rbtrees */
-	if (t->num_volatile_columns) {
-		volatile_objs = para_calloc(t->num_volatile_columns
-			* sizeof(struct osl_object));
-		FOR_EACH_VOLATILE_COLUMN(i, t, cd)
-			volatile_objs[t->columns[i].volatile_num] = objects[i];
-	}
-	t->num_rows++;
-//	PARA_DEBUG_LOG("adding new entry as row #%d\n", t->num_rows - 1);
-	ret = add_row_to_rbtrees(t, t->num_rows - 1, volatile_objs, row);
-	if (ret < 0)
-		goto out;
-//	PARA_DEBUG_LOG("added new entry as row #%d\n", t->num_rows - 1);
-	ret = 1;
-	goto out;
-rollback: /* rollback all changes made, ignore further errors */
-	for (i--; i >= 0; i--) {
-		enum osl_storage_type st;
-
-		cd = get_column_description(t->desc, i);
-		st = cd->storage_type;
-		if (st == OSL_NO_STORAGE)
-			continue;
-
-		if (st == OSL_MAPPED_STORAGE)
-			truncate_mapped_file(t, i, objects[i].size);
-		else /* disk storage */
-			delete_disk_storage_file(t, i, ds_name);
-	}
-	/* ignore error and return previous error value */
-	map_table(t, MAP_TBL_FL_VERIFY_INDEX);
-out:
-	free(new_row_index);
-	free(ds_name);
-	free(rb_parents);
-	free(rb_links);
-	return ret;
-}
-
-/**
- * Add a new row to an osl table.
- *
- * \param t Same meaning as osl_add_and_get_row().
- * \param objects Same meaning as osl_add_and_get_row().
- *
- * \return The return value of the underlying call to osl_add_and_get_row().
- *
- * This is equivalent to osl_add_and_get_row(t, objects, NULL).
- */
-int osl_add_row(struct osl_table *t, struct osl_object *objects)
-{
-	return osl_add_and_get_row(t, objects, NULL);
-}
-
-/**
- * Retrieve an object identified by row and column
- *
- * \param t Pointer to an open osl table.
- * \param r Pointer to the row.
- * \param col_num The column number.
- * \param object The result pointer.
- *
- * The column determined by \a col_num must be of type \p OSL_MAPPED_STORAGE
- * or \p OSL_NO_STORAGE, i.e. no disk storage objects may be retrieved by this
- * function.
- *
- * \return Positive if object was found, negative on errors. Possible errors
- * include: \p E_BAD_TABLE, \p E_BAD_STORAGE_TYPE.
- *
- * \sa osl_storage_type, osl_open_disk_object().
- */
-int osl_get_object(const struct osl_table *t, const struct osl_row *r,
-	unsigned col_num, struct osl_object *object)
-{
-	const struct osl_column_description *cd;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	cd = get_column_description(t->desc, col_num);
-	/* col must not be disk storage */
-	if (cd->storage_type == OSL_DISK_STORAGE)
-		return -E_BAD_STORAGE_TYPE;
-	if (cd->storage_type == OSL_MAPPED_STORAGE)
-		return get_mapped_object(t, col_num, r->num, object);
-	/* volatile */
-	*object = r->volatile_objects[t->columns[col_num].volatile_num];
-	return 1;
-}
-
-static int mark_mapped_object_invalid(const struct osl_table *t,
-		uint32_t row_num, unsigned col_num)
-{
-	struct osl_object obj;
-	char *p;
-	int ret = get_mapped_object(t, col_num, row_num, &obj);
-
-	if (ret < 0)
-		return ret;
-	p = obj.data;
-	p--;
-	*p = 0xff;
-	return 1;
-}
-
-/**
- * Delete a row from an osl table.
- *
- * \param t Pointer to an open osl table.
- * \param row Pointer to the row to delete.
- *
- * This removes all disk storage objects, removes all rbtree nodes,  and frees
- * all volatile objects belonging to the given row. For mapped columns, the
- * data is merely marked invalid and may be pruned from time to time by
- * para_fsck.
- *
- * \return Positive on success, negative on errors. Possible errors include:
- * \p E_BAD_TABLE, errors returned by osl_get_object().
- */
-int osl_del_row(struct osl_table *t, struct osl_row *row)
-{
-	struct osl_row *r = row;
-	int i, ret;
-	const struct osl_column_description *cd;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	PARA_INFO_LOG("deleting row %p\n", row);
-
-	if (t->num_disk_storage_columns) {
-		char *ds_name;
-		ret = disk_storage_name_of_row(t, r, &ds_name);
-		if (ret < 0)
-			goto out;
-		FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd)
-			delete_disk_storage_file(t, i, ds_name);
-		free(ds_name);
-	}
-	FOR_EACH_COLUMN(i, t->desc, cd) {
-		struct osl_column *col = t->columns + i;
-		enum osl_storage_type st = cd->storage_type;
-		remove_rb_node(t, i, r);
-		if (st == OSL_MAPPED_STORAGE) {
-			mark_mapped_object_invalid(t, r->num, i);
-			continue;
-		}
-		if (st == OSL_NO_STORAGE && !(cd->storage_flags & OSL_DONT_FREE))
-			free(r->volatile_objects[col->volatile_num].data);
-	}
-	if (t->num_mapped_columns) {
-		ret = mark_row_invalid(t, r->num);
-		if (ret < 0)
-			goto out;
-		t->num_invalid_rows++;
-	} else
-		t->num_rows--;
-	ret = 1;
-out:
-	free(r->volatile_objects);
-	free(r);
-	return ret;
-}
-
-/* test if column has an rbtree */
-static int check_rbtree_col(const struct osl_table *t, unsigned col_num,
-		struct osl_column **col)
-{
-	if (!t)
-		return -E_BAD_TABLE;
-	if (!(get_column_description(t->desc, col_num)->storage_flags & OSL_RBTREE))
-		return -E_BAD_STORAGE_FLAGS;
-	*col = t->columns + col_num;
-	return 1;
-}
-
-/**
- * Get the row that contains the given object.
- *
- * \param t Pointer to an open osl table.
- * \param col_num The number of the column to be searched.
- * \param obj The object to be looked up.
- * \param result Points to the row containing \a obj.
- *
- * Lookup \a obj in \a t and return the row containing \a obj. The column
- * specified by \a col_num must have an associated rbtree.
- *
- * \return Positive on success, negative on errors. If an error occurred, \a
- * result is set to \p NULL. Possible errors include: \p E_BAD_TABLE, \p
- * E_BAD_STORAGE_FLAGS, errors returned by get_mapped_object(), \p
- * E_RB_KEY_NOT_FOUND.
- *
- * \sa osl_storage_flags
- */
-int osl_get_row(const struct osl_table *t, unsigned col_num,
-		const struct osl_object *obj, struct osl_row **result)
-{
-	int ret;
-	struct rb_node *node;
-	struct osl_row *row;
-	struct osl_column *col;
-
-	*result = NULL;
-	ret = check_rbtree_col(t, col_num, &col);
-	if (ret < 0)
-		return ret;
-	ret = search_rbtree(obj, t, col_num, &node, NULL);
-	if (ret < 0)
-		return ret;
-	row = get_row_pointer(node, t->columns[col_num].rbtree_num);
-	*result = row;
-	return 1;
-}
-
-static int rbtree_loop(struct osl_column *col,  void *private_data,
-		osl_rbtree_loop_func *func)
-{
-	struct rb_node *n, *tmp;
-
-	/* this for-loop is safe against removal of an entry */
-	for (n = rb_first(&col->rbtree), tmp = n? rb_next(n) : NULL;
-			n;
-			n = tmp, tmp = tmp? rb_next(tmp) : NULL) {
-		struct osl_row *r = get_row_pointer(n, col->rbtree_num);
-		int ret = func(r, private_data);
-		if (ret < 0)
-			return ret;
-	}
-	return 1;
-}
-
-static int rbtree_loop_reverse(struct osl_column *col,  void *private_data,
-		osl_rbtree_loop_func *func)
-{
-	struct rb_node *n, *tmp;
-
-	/* safe against removal of an entry */
-	for (n = rb_last(&col->rbtree), tmp = n? rb_prev(n) : NULL;
-			n;
-			n = tmp, tmp = tmp? rb_prev(tmp) : NULL) {
-		struct osl_row *r = get_row_pointer(n, col->rbtree_num);
-		int ret = func(r, private_data);
-		if (ret < 0)
-			return ret;
-	}
-	return 1;
-}
-
-/**
- * Loop over all nodes in an rbtree.
- *
- * \param t Pointer to an open osl table.
- * \param col_num The column to use for iterating over the elements.
- * \param private_data Pointer that gets passed to \a func.
- * \param func The function to be called for each node in the rbtree.
- *
- * This function does an in-order walk of the rbtree associated with \a
- * col_num. It is an error if the \p OSL_RBTREE flag is not set for this
- * column. For each node in the rbtree, the given function \a func is called
- * with two pointers as arguments: The first osl_row* argument points to the
- * row that contains the object corresponding to the rbtree node currently
- * traversed, and the \a private_data pointer is passed verbatim to \a func as the
- * second argument. The loop terminates either if \a func returns a negative
- * value, or if all nodes of the tree have been visited.
- *
- *
- * \return Positive on success, negative on errors. If the termination of the
- * loop was caused by \a func returning a negative value, this value is
- * returned.
- *
- * \sa osl_storage_flags, osl_rbtree_loop_reverse(), osl_compare_func.
- */
-int osl_rbtree_loop(const struct osl_table *t, unsigned col_num,
-	void *private_data, osl_rbtree_loop_func *func)
-{
-	struct osl_column *col;
-
-	int ret = check_rbtree_col(t, col_num, &col);
-	if (ret < 0)
-		return ret;
-	return rbtree_loop(col, private_data, func);
-}
-
-/**
- * Loop over all nodes in an rbtree in reverse order.
- *
- * \param t Identical meaning as in \p osl_rbtree_loop().
- * \param col_num Identical meaning as in \p osl_rbtree_loop().
- * \param private_data Identical meaning as in \p osl_rbtree_loop().
- * \param func Identical meaning as in \p osl_rbtree_loop().
- *
- * This function is identical to \p osl_rbtree_loop(), the only difference
- * is that the tree is walked in reverse order.
- *
- * \return The same return value as \p osl_rbtree_loop().
- *
- * \sa osl_rbtree_loop().
- */
-int osl_rbtree_loop_reverse(const struct osl_table *t, unsigned col_num,
-	void *private_data, osl_rbtree_loop_func *func)
-{
-	struct osl_column *col;
-
-	int ret = check_rbtree_col(t, col_num, &col);
-	if (ret < 0)
-		return ret;
-	return rbtree_loop_reverse(col, private_data, func);
-}
-
-/* TODO: Rollback changes on errors */
-static int rename_disk_storage_objects(struct osl_table *t,
-		struct osl_object *old_obj, struct osl_object *new_obj)
-{
-	int i, ret;
-	const struct osl_column_description *cd;
-	char *old_ds_name, *new_ds_name;
-
-	if (!t->num_disk_storage_columns)
-		return 1; /* nothing to do */
-	if (old_obj->size == new_obj->size && !memcmp(new_obj->data,
-			old_obj->data, new_obj->size))
-		return 1; /* object did not change */
-	old_ds_name = disk_storage_name_of_object(t, old_obj);
-	new_ds_name = disk_storage_name_of_object(t, new_obj);
-	FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd) {
-		char *old_filename, *new_filename;
-		ret = create_disk_storage_object_dir(t, i, new_ds_name);
-		if (ret < 0)
-			goto out;
-		old_filename = disk_storage_path(t, i, old_ds_name);
-		new_filename = disk_storage_path(t, i, new_ds_name);
-		ret = para_rename(old_filename, new_filename);
-		free(old_filename);
-		free(new_filename);
-		if (ret < 0)
-			goto out;
-	}
-	ret = 1;
-out:
-	free(old_ds_name);
-	free(new_ds_name);
-	return ret;
-
-}
-
-/**
- * Change an object in an osl table.
- *
- * \param t Pointer to an open osl table.
- * \param r Pointer to the row containing the object to be updated.
- * \param col_num Number of the column containing the object to be updated.
- * \param obj Pointer to the replacement object.
- *
- * This function  gets rid of all references to the old object. This includes
- * removal of the rbtree node in case there is an rbtree associated with \a
- * col_num. It then inserts \a obj into the table and the rbtree if necessary.
- *
- * If the \p OSL_RBTREE flag is set for \a col_num, you \b MUST call this
- * function in order to change the contents of an object, even for volatile or
- * mapped columns of constant size (which may be updated directly if \p
- * OSL_RBTREE is not set).  Otherwise the rbtree might become corrupted.
- *
- * \return Standard
- */
-int osl_update_object(struct osl_table *t, const struct osl_row *r,
-		unsigned col_num, struct osl_object *obj)
-{
-	struct osl_column *col;
-	const struct osl_column_description *cd;
-	int ret;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	col = &t->columns[col_num];
-	cd = get_column_description(t->desc, col_num);
-	PARA_DEBUG_LOG("updating column %u of %s\n", col_num, t->desc->name);
-	if (cd->storage_flags & OSL_RBTREE) {
-		if (search_rbtree(obj, t, col_num, NULL, NULL) > 0)
-			return -E_RB_KEY_EXISTS;
-	}
-	if (cd->storage_flags & OSL_FIXED_SIZE) {
-		if (obj->size != cd->data_size)
-			return -E_BAD_DATA_SIZE;
-	}
-	remove_rb_node(t, col_num, r);
-	if (cd->storage_type == OSL_NO_STORAGE) { /* TODO: If fixed size, reuse object? */
-		free(r->volatile_objects[col->volatile_num].data);
-		r->volatile_objects[col->volatile_num] = *obj;
-	} else if (cd->storage_type == OSL_DISK_STORAGE) {
-		char *ds_name;
-		ret = disk_storage_name_of_row(t, r, &ds_name);
-		if (ret < 0)
-			return ret;
-		ret = delete_disk_storage_file(t, col_num, ds_name);
-		if (ret < 0 && !is_errno(-ret, ENOENT)) {
-			free(ds_name);
-			return ret;
-		}
-		ret = write_disk_storage_file(t, col_num, obj, ds_name);
-		free(ds_name);
-		if (ret < 0)
-			return ret;
-	} else { /* mapped storage */
-		struct osl_object old_obj;
-		ret = get_mapped_object(t, col_num, r->num, &old_obj);
-		if (ret < 0)
-			return ret;
-		/*
-		 * If the updated column is the disk storage name column, the
-		 * disk storage name changes, so we have to rename all disk
-		 * storage objects accordingly.
-		 */
-		if (col_num == t->disk_storage_name_column) {
-			ret = rename_disk_storage_objects(t, &old_obj, obj);
-			if (ret < 0)
-				return ret;
-		}
-		if (cd->storage_flags & OSL_FIXED_SIZE)
-			memcpy(old_obj.data, obj->data, cd->data_size);
-		else { /* TODO: if the size doesn't change, use old space */
-			uint32_t new_data_map_size;
-			char *row_index;
-			ret = get_row_index(t, r->num, &row_index);
-			if (ret < 0)
-				return ret;
-			ret = mark_mapped_object_invalid(t, r->num, col_num);
-			if (ret < 0)
-				return ret;
-			unmap_column(t, col_num);
-			ret = append_map_file(t, col_num, obj,
-				&new_data_map_size);
-			if (ret < 0)
-				return ret;
-			ret = map_column(t, col_num);
-			if (ret < 0)
-				return ret;
-			update_cell_index(row_index, col, new_data_map_size,
-				obj->size);
-		}
-	}
-	if (cd->storage_flags & OSL_RBTREE) {
-		ret = insert_rbtree(t, col_num, r, obj);
-		if (ret < 0)
-			return ret;
-	}
-	return 1;
-}
-
-/**
- * Retrieve an object of type \p OSL_DISK_STORAGE by row and column.
- *
- * \param t Pointer to an open osl table.
- * \param r Pointer to the row containing the object.
- * \param col_num The column number.
- * \param obj Points to the result upon successful return.
- *
- * For columns of type \p OSL_DISK_STORAGE, this function must be used to
- * retrieve one of its containing objects. Afterwards, osl_close_disk_object()
- * must be called in order to deallocate the resources.
- *
- * \return Positive on success, negative on errors. Possible errors include:
- * \p E_BAD_TABLE, \p E_BAD_STORAGE_TYPE, errors returned by osl_get_object().
- *
- * \sa osl_get_object(), osl_storage_type, osl_close_disk_object().
- */
-int osl_open_disk_object(const struct osl_table *t, const struct osl_row *r,
-		unsigned col_num, struct osl_object *obj)
-{
-	const struct osl_column_description *cd;
-	char *ds_name, *filename;
-	int ret;
-
-	if (!t)
-		return -E_BAD_TABLE;
-	cd = get_column_description(t->desc, col_num);
-	if (cd->storage_type != OSL_DISK_STORAGE)
-		return -E_BAD_STORAGE_TYPE;
-
-	ret = disk_storage_name_of_row(t, r, &ds_name);
-	if (ret < 0)
-		return ret;
-	filename = disk_storage_path(t, col_num, ds_name);
-	free(ds_name);
-	PARA_DEBUG_LOG("filename: %s\n", filename);
-	ret = mmap_full_file(filename, O_RDONLY, &obj->data, &obj->size, NULL);
-	free(filename);
-	return ret;
-}
-
-/**
- * Free resources that were allocated during osl_open_disk_object().
- *
- * \param obj Pointer to the object previously returned by open_disk_object().
- *
- * \return The return value of the underlying call to para_munmap().
- *
- * \sa para_munmap().
- */
-int osl_close_disk_object(struct osl_object *obj)
-{
-	return para_munmap(obj->data, obj->size);
-}
-
-/**
- * Get the number of rows of the given table.
- *
- * \param t Pointer to an open osl table.
- * \param num_rows Result is returned here.
- *
- * The number of rows returned via \a num_rows excluding any invalid rows.
- *
- * \return Positive on success, \p -E_BAD_TABLE if \a t is \p NULL.
- */
-int osl_get_num_rows(const struct osl_table *t, unsigned *num_rows)
-{
-	if (!t)
-		return -E_BAD_TABLE;
-	assert(t->num_rows >= t->num_invalid_rows);
-	*num_rows = t->num_rows - t->num_invalid_rows;
-	return 1;
-}
-
-/**
- * Get the rank of a row.
- *
- * \param t An open osl table.
- * \param r The row to get the rank of.
- * \param col_num The number of an rbtree column.
- * \param rank Result pointer.
- *
- * The rank is, by definition, the position of the row in the linear order
- * determined by an in-order tree walk of the rbtree associated with column
- * number \a col_num of \a table.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa osl_get_nth_row().
- */
-int osl_get_rank(const struct osl_table *t, struct osl_row *r,
-		unsigned col_num, unsigned *rank)
-{
-	struct osl_object obj;
-	struct osl_column *col;
-	struct rb_node *node;
-	int ret = check_rbtree_col(t, col_num, &col);
-
-	if (ret < 0)
-		return ret;
-	ret = osl_get_object(t, r, col_num, &obj);
-	if (ret < 0)
-		return ret;
-	ret = search_rbtree(&obj, t, col_num, &node, NULL);
-	if (ret < 0)
-		return ret;
-	ret = rb_rank(node, rank);
-	if (ret < 0)
-		return -E_BAD_ROW;
-	return 1;
-}
-
-/**
- * Get the row with n-th greatest value.
- *
- * \param t Pointer to an open osl table.
- * \param col_num The column number.
- * \param n The rank of the desired row.
- * \param result Row is returned here.
- *
- * Retrieve the n-th order statistic with respect to the compare function
- * of the rbtree column \a col_num. In other words, get that row with
- * \a n th greatest value in column \a col_num. It's an error if
- * \a col_num is not a rbtree column, or if \a n is larger than the
- * number of rows in the table.
- *
- * \return Positive on success, negative on errors. Possible errors:
- * \p E_BAD_TABLE, \p E_BAD_STORAGE_FLAGS, \p E_RB_KEY_NOT_FOUND.
- *
- * \sa osl_storage_flags, osl_compare_func, osl_get_row(),
- * osl_rbtree_last_row(), osl_rbtree_first_row(), osl_get_rank().
- */
-int osl_get_nth_row(const struct osl_table *t, unsigned col_num,
-		unsigned n, struct osl_row **result)
-{
-	struct osl_column *col;
-	struct rb_node *node;
-	unsigned num_rows;
-	int ret;
-
-	if (n == 0)
-		return -E_RB_KEY_NOT_FOUND;
-	ret = osl_get_num_rows(t, &num_rows);
-	if (ret < 0)
-		return ret;
-	if (n > num_rows)
-		return -E_RB_KEY_NOT_FOUND;
-	ret = check_rbtree_col(t, col_num, &col);
-	if (ret < 0)
-		return ret;
-	node = rb_nth(col->rbtree.rb_node, n);
-	if (!node)
-		return -E_RB_KEY_NOT_FOUND;
-	*result = get_row_pointer(node, col->rbtree_num);
-	return 1;
-}
-
-/**
- * Get the row corresponding to the smallest rbtree node of a column.
- *
- * \param t An open rbtree table.
- * \param col_num The number of the rbtree column.
- * \param result A pointer to the first row is returned here.
- *
- * The rbtree node of the smallest object (with respect to the corresponding
- * compare function) is selected and the row containing this object is
- * returned. It is an error if \a col_num refers to a column without an
- * associated rbtree.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa osl_get_nth_row(), osl_rbtree_last_row().
- */
-int osl_rbtree_first_row(const struct osl_table *t, unsigned col_num,
-		struct osl_row **result)
-{
-	return osl_get_nth_row(t, col_num, 1, result);
-}
-
-/**
- * Get the row corresponding to the greatest rbtree node of a column.
- *
- * \param t The same meaning as in \p osl_rbtree_first_row().
- * \param col_num The same meaning as in \p osl_rbtree_first_row().
- * \param result The same meaning as in \p osl_rbtree_first_row().
- *
- * This function works just like osl_rbtree_first_row(), the only difference
- * is that the row containing the greatest rather than the smallest object is
- * returned.
- *
- * \return Positive on success, negative on errors.
- *
- * \sa osl_get_nth_row(), osl_rbtree_first_row().
- */
-int osl_rbtree_last_row(const struct osl_table *t, unsigned col_num,
-		struct osl_row **result)
-{
-	unsigned num_rows;
-	int ret = osl_get_num_rows(t, &num_rows);
-
-	if (ret < 0)
-		return ret;
-	return osl_get_nth_row(t, col_num, num_rows, result);
-}