+++ /dev/null
-/*
- * Copyright (C) 2007-2009 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
-
-/** \file osl_core.h Object storage layer details, not visible to users. */
-
-#include "rbtree.h"
-#include "osl.h"
-#include "string.h"
-#include "portable_io.h"
-#include "hash.h"
-
-/** Internal representation of a column of an osl table. */
-struct osl_column {
- /** The memory mapping of this comumn (only used for mapped columns). */
- struct osl_object data_map;
- /** The root of the rbtree (only used for columns with rbtrees). */
- struct rb_root rbtree;
- /** The index in the array of rb nodes (only used for columns with rbtrees). */
- unsigned rbtree_num;
- /** Index for volatile_objects of struct osl_row. */
- unsigned volatile_num;
- /**
- * Starting point of the data for this column within the index
- * (only used for mapped columns).
- */
- uint16_t index_offset;
- /**
- * The hash value of the name of this column.
- *
- * This is only used for mapped and disk storage columns).
- */
- HASH_TYPE name_hash[HASH_SIZE];
-};
-
-/** Internal representation of an osl table */
-struct osl_table {
- /** Pointer to the table description */
- const struct osl_table_description *desc;
- /** The size of the index header of this table. */
- uint16_t index_header_size;
- /** Contains the mapping of the table's index file */
- struct osl_object index_map;
- /** Total number of rows, including invalid rows. */
- unsigned num_rows;
- /** Keeps track of the number of invalid rows in the table. */
- uint32_t num_invalid_rows;
- /** Number of columns of type \p OSL_MAPPED_STORAGE. */
- unsigned num_mapped_columns;
- /** Number of columns of type \p OSL_NO_STORAGE. */
- unsigned num_volatile_columns;
- /** Number of columns of type \p OSL_DISK_STORAGE. */
- unsigned num_disk_storage_columns;
- /** Number of columns with associated rbtree. */
- unsigned num_rbtrees;
- /**
- * The number of the column that determines the name of the disk
- * storage objects.
- */
- unsigned disk_storage_name_column;
- /** The number of bytes of an index entry of a row. */
- unsigned row_index_size;
- /** Pointer to the internal representation of the columns. */
- struct osl_column *columns;
-};
-
-/** Internal representation of a row of an osl table */
-struct osl_row {
- /**
- * The row number.
- *
- * It is only used if there is at least one mapped column.
- */
- off_t num;
- /** Array of size \a num_volatile_columns. */
- struct osl_object *volatile_objects;
-};
-
-int read_table_desc(struct osl_object *map, struct osl_table_description *desc);
-int init_table_structure(const struct osl_table_description *desc,
- struct osl_table **table_ptr);
-int row_is_invalid(struct osl_table *t, uint32_t row_num);
-int get_mapped_object(const struct osl_table *t, unsigned col_num,
- uint32_t row_num, struct osl_object *obj);
-int para_truncate(const char *filename, off_t size);
-int unmap_table(struct osl_table *t, enum osl_close_flags flags);
-int init_rbtrees(struct osl_table *t);
-
-/**
- * Flags to be specified for map_table().
- *
- * \sa map_table().
- */
-enum map_table_flags {
- /**
- * Check whether the entries in the table index match the entries in
- * the table description.
- */
- MAP_TBL_FL_VERIFY_INDEX = 1,
- /** Do not complain even if the dirty flag is set. */
- MAP_TBL_FL_IGNORE_DIRTY = 2,
- /** Use read-only mappings. */
- MAP_TBL_FL_MAP_RDONLY = 4
-};
-
-int map_table(struct osl_table *t, enum map_table_flags flags);
-void clear_rbtrees(struct osl_table *t);
-int mark_row_invalid(struct osl_table *t, uint32_t row_num);
-
-
-/**
- * Get the description of a column by column number
- *
- * \param d Pointer to the table description.
- * \param col_num The number of the column to get the description for.
- *
- * \return The table description.
- *
- * \sa struct osl_column_description.
- */
-_static_inline_ struct osl_column_description *get_column_description(
- const struct osl_table_description *d, unsigned col_num)
-{
- return &d->column_descriptions[col_num];
-}
-
-/**
- * Format of the header of the index file of an osl table.
- *
- * Bytes 16-31 are currently unused.
- *
- * \sa enum index_column_desc_offsets, HASH_SIZE, osl_table_flags.
- */
-enum index_header_offsets {
- /** Bytes 0-8: PARASLASH. */
- IDX_PARA_MAGIC = 0,
- /** Byte 9: Dirty flag (nonzero if table is mapped). */
- IDX_DIRTY_FLAG = 9,
- /** Byte 10: osl table version number. */
- IDX_VERSION = 10,
- /** Byte 11: Table flags.*/
- IDX_TABLE_FLAGS = 11,
- /** Byte 12,13: Number of columns. */
- IDX_NUM_COLUMNS,
- /** Byte 14,15 Size of the index header. */
- IDX_HEADER_SIZE = 14,
- /** Column descriptions start here. */
- IDX_COLUMN_DESCRIPTIONS = 32
-};
-
-/**
- * Format of the column description in the index header.
- *
- * \sa index_header_offsets.
- */
-enum index_column_desc_offsets {
- /** Bytes 0,1: Storage_type. */
- IDX_CD_STORAGE_TYPE = 0,
- /** Bytes 2,3: Storage_flags. */
- IDX_CD_STORAGE_FLAGS = 2,
- /** Bytes 4 - 7: Data_size (only used for fixed size columns). */
- IDX_CD_DATA_SIZE = 4,
- /** Bytes 8 - ... Name of the column. */
- IDX_CD_NAME = 8,
-};
-
-/** Magic string contained in the header of the index file of each osl table. */
-#define PARA_MAGIC "PARASLASH"
-
-/**
- * The minimal number of bytes for a column in the index header.
- *
- * The column name starts at byte IDX_CD_NAME and must at least contain one
- * character, plus the terminating NULL byte.
- */
-#define MIN_IDX_COLUMN_DESCRIPTION_SIZE (IDX_CD_NAME + 2)
-
-/**
- * Get the number of bytes used for a column in the index header.
- *
- * \param name The name of the column.
- *
- * The amount of space used for a column in the index header of a table depends
- * on the (length of the) name of the column.
- *
- * \return The total number of bytes needed to store one column of this name.
- */
-_static_inline_ size_t index_column_description_size(const char *name)
-{
- return MIN_IDX_COLUMN_DESCRIPTION_SIZE + strlen(name) - 1;
-}
-
-#define CURRENT_TABLE_VERSION 1
-#define MIN_TABLE_VERSION 1
-#define MAX_TABLE_VERSION 1
-/** An index header must be at least that many bytes long. */
-#define MIN_INDEX_HEADER_SIZE(num_cols) (MIN_IDX_COLUMN_DESCRIPTION_SIZE \
- * num_cols + IDX_COLUMN_DESCRIPTIONS)
-
-/**
- * Get the number of rows from the size of the memory mapping.
- *
- * \param t Pointer to an open table.
- *
- * \return The number of rows, including invalid rows.
- */
-_static_inline_ unsigned table_num_rows(const struct osl_table *t)
-{
- return (t->index_map.size - t->index_header_size)
- / t->row_index_size;
-}
-
-/**
- * Get the path of the index file from a table description.
- *
- * \param d The table description.
- *
- * \return The full path of the index file. Result must be freed by
- * the caller.
- */
-_static_inline_ char *index_filename(const struct osl_table_description *d)
-{
- return make_message("%s/%s/index", d->dir, d->name);
-}
-
-/**
- * Get the path of storage of a column.
- *
- * \param t Pointer to an initialized table.
- * \param col_num The number of the column to get the path for.
- *
- * \return The full path of the mapped data file (mapped storage) or the
- * data directory (disk storage). Result must be freed by the caller.
- *
- * \sa osl_storage_type.
- */
-_static_inline_ char *column_filename(const struct osl_table *t, unsigned col_num)
-{
- char asc[2 * HASH_SIZE + 1];
- hash_to_asc(t->columns[col_num].name_hash, asc);
- return make_message("%s/%s/%s", t->desc->dir, t->desc->name, asc);
-}
-
-/**
- * Get the start of an index entry
- *
- * \param t Pointer to a table which has been mapped.
- * \param row_num The number of the row whose index entry should be retrieved.
- * \param row_index Result pointer.
- *
- * \return Positive on success, \p -E_INDEX_CORRUPTION otherwise.
- *
- * \sa get_cell_index().
- */
-_static_inline_ int get_row_index(const struct osl_table *t, uint32_t row_num,
- char **row_index)
-{
- uint32_t index_offset;
- index_offset = t->index_header_size + t->row_index_size * row_num;
- if (index_offset + 8 > t->index_map.size) {
- *row_index = NULL;
- return -E_INDEX_CORRUPTION;
- }
- *row_index = (char *)(t->index_map.data) + index_offset;
- return 1;
-}
-
-/**
- * Get the index entry of a row/column pair.
- *
- * \param t Pointer to a table which has been mapped.
- * \param row_num The number of the row whose index entry should be retrieved.
- * \param col_num The number of the column whose index entry should be retrieved.
- * \param cell_index Result pointer.
- *
- * \return Positive on success, \p -E_INDEX_CORRUPTION otherwise.
- *
- * \sa get_row_index().
- */
-_static_inline_ int get_cell_index(const struct osl_table *t, uint32_t row_num,
- uint32_t col_num, char **cell_index)
-{
- int ret = get_row_index(t, row_num, cell_index);
- if (ret < 0)
- return ret;
- *cell_index += t->columns[col_num].index_offset;
- return ret;
-}
-
-/**
- * Change an index entry of a column after object was added.
- *
- * \param row_index Pointer to the index of the row to update.
- * \param col Pointer to the column.
- * \param map_size The new size of the data file.
- * \param object_size The size of the object just appended to the data file.
- *
- * This is called right after an object was appended to the data file for a
- * mapped column.
- *
- * \sa get_row_index().
- */
-_static_inline_ void update_cell_index(char *row_index, struct osl_column *col,
- uint32_t map_size, uint32_t object_size)
-{
- write_u32(row_index + col->index_offset, map_size - object_size - 1);
- write_u32(row_index + col->index_offset + 4, object_size + 1);
-}
-
-/**
- * Get the full path of a disk storage object
- *
- * \param t Pointer to an initialized table.
- * \param col_num The number of the column the disk storage object belongs to.
- * \param ds_name The disk storage name of the object.
- *
- * \return Pointer to the full path which must be freed by the caller.
- *
- * \sa column_filename(), disk_storage_name_of_row().
- */
-_static_inline_ char *disk_storage_path(const struct osl_table *t,
- unsigned col_num, const char *ds_name)
-{
- char *dirname = column_filename(t, col_num);
- char *filename = make_message("%s/%s", dirname, ds_name);
- free(dirname);
- return filename;
-}
-
-/**
- * Get the column description of the next column of a given type.
- *
- * \param type the desired storage type.
- * \param col_num the column to start the search.
- * \param t the osl table.
- * \param cd result is returned here.
- *
- * \return On success, \a cd contains the column description of the next column
- * of type \a type, and the number of that column is returned. Otherwise, \a
- * cd is set to \p NULL and the function returns t->num_columns + 1.
- *
- * \sa FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN, FOR_EACH_RBTREE_COLUMN,
- * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN, osl_storage_type.
- */
-_static_inline_ int next_column_of_type(enum osl_storage_type type, int col_num,
- const struct osl_table *t,
- const struct osl_column_description **cd)
-{
- *cd = NULL;
- while (col_num < t->desc->num_columns) {
- *cd = get_column_description(t->desc, col_num);
- if ((*cd)->storage_type == type)
- break;
- col_num++;
- }
- return col_num;
-}
-
-/**
- * Find the next column with an associated rbtree.
- *
- * \param col_num The column to start the search.
- * \param t The osl table.
- * \param cd Result is returned here.
-
- * \return On success, \a cd contains the column description of the next column
- * with associated rbtree, and the number of that column is returned.
- * Otherwise, \a cd is set to \p NULL and the function returns t->num_columns +
- * 1.
- *
- * \sa FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN, FOR_EACH_RBTREE_COLUMN,
- * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN, osl_storage_flags.
- */
-_static_inline_ int next_rbtree_column(int col_num, const struct osl_table *t,
- const struct osl_column_description **cd)
-{
- *cd = NULL;
- while (col_num < t->desc->num_columns) {
- *cd = get_column_description(t->desc, col_num);
- if ((*cd)->storage_flags & OSL_RBTREE)
- break;
- col_num++;
- }
- return col_num;
-}
-
-
-/* quite some dirty hacks */
-
-/** Round up size of struct osl_row to multiple of 8 */
-#define RB_NODES_OFFSET ((sizeof(struct osl_row) + 7) / 8 * 8)
-
-/**
- * Allocate a new osl row.
- *
- * \param num_rbtrees The number of rbtrees for this row.
- *
- * \return A pointer to a zeroed-out area suitable for holding an osl row
- * with \a num_rbtrees rbtree columns.
- */
-_static_inline_ struct osl_row *allocate_row(unsigned num_rbtrees)
-{
- size_t s = RB_NODES_OFFSET + num_rbtrees * sizeof(struct rb_node);
- return para_calloc(s);
-}
-
-/**
- * Compute the pointer to a rbtree node embedded in a osl row.
- *
- * \param row The row to extract the rbtree pointer from.
- * \param rbtree_num The number of the rbtree node to extract.
- *
- * \return A pointer to the \a rbtree_num th node contained in \a row.
- */
-_static_inline_ struct rb_node *get_rb_node_pointer(const struct osl_row *row, uint32_t rbtree_num)
-{
- return ((struct rb_node *)(((char *)row) + RB_NODES_OFFSET)) + rbtree_num;
-}
-
-/**
- * Get a pointer to the struct containing the given rbtree node.
- *
- * \param node Pointer to the rbtree node.
- * \param rbtree_num Number of \a node in the array of rbtree nodes.
- *
- * \return A pointer to the row containing \a node.
- */
-_static_inline_ struct osl_row *get_row_pointer(const struct rb_node *node,
- unsigned rbtree_num)
-{
- node -= rbtree_num;
- return (struct osl_row *)(((char *)node) - RB_NODES_OFFSET);
-}
-
-/**
- * Compute a cryptographic hash of an osl object.
- *
- * \param obj the Object to compute the hash value from.
- * \param hash Result is returned here.
- */
-_static_inline_ void hash_object(const struct osl_object *obj, HASH_TYPE *hash)
-{
- hash_function(obj->data, obj->size, hash);
-}
-
-/**
- * Get the relative path of an object, given the hash value.
- *
- * \param t Pointer to an initialized osl table.
- * \param hash An arbitrary hash value.
- *
- * This function is typically called with \a hash being the hash of the object
- * stored in the disk storage name column of a row. If the OSL_LARGE_TABLE
- * flag is set, the first two hex digits get separated with a slash from the
- * remaining digits.
- *
- * \return The relative path for all disk storage objects corresponding to \a
- * hash.
- *
- * \sa struct osl_table:disk_storage_name_column.
- */
-_static_inline_ char *disk_storage_name_of_hash(const struct osl_table *t, HASH_TYPE *hash)
-{
- char asc[2 * HASH_SIZE + 2];
-
- hash_to_asc(hash, asc);
- if (t->desc->flags & OSL_LARGE_TABLE)
- return make_message("%.2s/%s", asc, asc + 2);
- return para_strdup(asc);
-}
-
-/**
- * A wrapper for rename(2).
- *
- * \param old_path The source path.
- * \param new_path The destination path.
- *
- * \return Standard.
- *
- * \sa rename(2).
- */
-_static_inline_ int para_rename(const char *old_path, const char *new_path)
-{
- if (rename(old_path, new_path) < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- return 1;
-}
-
-/**
- * Iterate over each column of an initialized table.
- *
- * \param col A pointer to a struct osl_column.
- * \param desc Pointer to the table description.
- * \param cd Pointer to struct osl_column_description.
- *
- * On each iteration, \a col will point to the next column of the table and \a
- * cd will point to the column description of this column.
- *
- * \sa struct osl_column FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
- * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
- * FOR_EACH_VOLATILE_COLUMN.
- */
-#define FOR_EACH_COLUMN(col, desc, cd) \
- for (col = 0; col < (desc)->num_columns && \
- (cd = get_column_description(desc, col)); col++)
-
-/**
- * Iterate over each column with associated rbtree.
- *
- * \param col Same meaning as in FOR_EACH_COLUMN().
- * \param table Same meaning as in FOR_EACH_COLUMN().
- * \param cd Same meaning as in FOR_EACH_COLUMN().
- *
- * \sa osl_storage_flags::OSL_RBTREE, FOR_EACH_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
- * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
- * FOR_EACH_VOLATILE_COLUMN.
- */
-#define FOR_EACH_RBTREE_COLUMN(col, table, cd) \
- for (col = next_rbtree_column(0, table, &cd); \
- col < table->desc->num_columns; \
- col = next_rbtree_column(++col, table, &cd))
-
-/**
- * Iterate over each column of given storage type.
- *
- * \param type The osl_storage_type to iterate over.
- * \param col Same meaning as in FOR_EACH_COLUMN().
- * \param table Same meaning as in FOR_EACH_COLUMN().
- * \param cd Same meaning as in FOR_EACH_COLUMN().
- *
- * \sa osl_storage_type, FOR_EACH_COLUMN, FOR_EACH_RBTREE_COLUMN,
- * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
- * FOR_EACH_VOLATILE_COLUMN.
- */
-#define FOR_EACH_COLUMN_OF_TYPE(type, col, table, cd) \
- for (col = next_column_of_type(type, 0, table, &cd); \
- col < table->desc->num_columns; \
- col = next_column_of_type(type, ++col, table, &cd))
-
-/**
- * Iterate over each mapped column.
- *
- * \param col Same meaning as in FOR_EACH_COLUMN().
- * \param table Same meaning as in FOR_EACH_COLUMN().
- * \param cd Same meaning as in FOR_EACH_COLUMN().
- *
- * Just like FOR_EACH_COLUMN(), but skip columns which are
- * not of type \p OSL_MAPPED_STORAGE.
- *
- * \sa osl_storage_flags::OSL_MAPPED_STORAGE, FOR_EACH_COLUMN,
- * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
- * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN.
- */
-#define FOR_EACH_MAPPED_COLUMN(col, table, cd) \
- FOR_EACH_COLUMN_OF_TYPE(OSL_MAPPED_STORAGE, col, table, cd)
-
-/**
- * Iterate over each disk storage column.
- *
- * \param col Same meaning as in FOR_EACH_COLUMN().
- * \param table Same meaning as in FOR_EACH_COLUMN().
- * \param cd Same meaning as in FOR_EACH_COLUMN().
- *
- * Just like FOR_EACH_COLUMN(), but skip columns which are
- * not of type \p OSL_DISK_STORAGE.
- *
- * \sa osl_storage_flags::OSL_DISK_STORAGE, FOR_EACH_COLUMN,
- * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN,
- * FOR_EACH_VOLATILE_COLUMN.
- */
-#define FOR_EACH_DISK_STORAGE_COLUMN(col, table, cd) \
- FOR_EACH_COLUMN_OF_TYPE(OSL_DISK_STORAGE, col, table, cd)
-
-/**
- * Iterate over each volatile column.
- *
- * \param col Same meaning as in FOR_EACH_COLUMN().
- * \param table Same meaning as in FOR_EACH_COLUMN().
- * \param cd Same meaning as in FOR_EACH_COLUMN().
- *
- * Just like FOR_EACH_COLUMN(), but skip columns which are
- * not of type \p OSL_NO_STORAGE.
- *
- * \sa osl_storage_flags::OSL_NO_STORAGE, FOR_EACH_COLUMN,
- * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN,
- * FOR_EACH_DISK_STORAGE_COLUMN.
- */
-#define FOR_EACH_VOLATILE_COLUMN(col, table, cd) \
- FOR_EACH_COLUMN_OF_TYPE(OSL_NO_STORAGE, col, table, cd)
projects / paraslash.git / blobdiff