2 * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file osl_core.h Object storage layer details, not visible to users. */
14 /** Internal representation of a column of an osl table. */
16 /** The memory mapping of this comumn (only used for mapped columns). */
17 struct osl_object data_map;
18 /** The root of the rbtree (only used for columns with rbtrees). */
19 struct rb_root rbtree;
20 /** The index in the array of rb nodes (only used for columns with rbtrees). */
22 /** Index for volatile_objects of struct osl_row. */
23 unsigned volatile_num;
25 * Starting point of the data for this column within the index
26 * (only used for mapped columns).
28 uint16_t index_offset;
30 * The hash value of the name of this column.
32 * This is only used for mapped and disk storage columns).
34 HASH_TYPE name_hash[HASH_SIZE];
37 /** Internal representation of an osl table */
39 /** Pointer to the table description */
40 const struct osl_table_description *desc;
41 /** The size of the index header of this table. */
42 uint16_t index_header_size;
43 /** Contains the mapping of the table's index file */
44 struct osl_object index_map;
45 /** Total number of rows, including invalid rows. */
47 /** Keeps track of the number of invalid rows in the table. */
48 uint32_t num_invalid_rows;
49 /** Number of columns of type \p OSL_MAPPED_STORAGE. */
50 unsigned num_mapped_columns;
51 /** Number of columns of type \p OSL_NO_STORAGE. */
52 unsigned num_volatile_columns;
53 /** Number of columns of type \p OSL_DISK_STORAGE. */
54 unsigned num_disk_storage_columns;
55 /** Number of columns with associated rbtree. */
58 * The number of the column that determines the name of the disk
61 unsigned disk_storage_name_column;
62 /** The number of bytes of an index entry of a row. */
63 unsigned row_index_size;
64 /** Pointer to the internal representation of the columns. */
65 struct osl_column *columns;
68 /** Internal representation of a row of an osl table */
70 /** The row number only present if there is at least one mapped column. */
72 /** Array of size \a num_volatile_columns. */
73 struct osl_object *volatile_objects;
76 int read_table_desc(struct osl_object *map, struct osl_table_description *desc);
77 int init_table_structure(const struct osl_table_description *desc,
78 struct osl_table **table_ptr);
79 int row_is_invalid(struct osl_table *t, uint32_t id);
80 int get_mapped_object(const struct osl_table *t, unsigned col_num,
81 uint32_t id, struct osl_object *obj);
82 int para_truncate(const char *filename, off_t size);
83 int unmap_table(struct osl_table *t, enum osl_close_flags flags);
84 int init_rbtrees(struct osl_table *t);
87 * Flags to be specified for map_table().
91 enum map_table_flags {
93 * Check whether the entries in the table index match the entries in
94 * the table desctiption.
96 MAP_TBL_FL_VERIFY_INDEX = 1,
97 /** Do not complain even if the dirty flag is set. */
98 MAP_TBL_FL_IGNORE_DIRTY = 2,
99 /** Use read-only mappings. */
100 MAP_TBL_FL_MAP_RDONLY = 4
103 int map_table(struct osl_table *t, enum map_table_flags flags);
104 void clear_rbtrees(struct osl_table *t);
105 int mark_row_invalid(struct osl_table *t, uint32_t row_num);
109 * Get the description of a column by column number
111 * \param d Pointer to the table description.
112 * \param col_num The number of the column to get the desctiption for.
114 * \return The table description.
116 * \sa struct osl_column_description.
118 _static_inline_ struct osl_column_description *get_column_description(
119 const struct osl_table_description *d, unsigned col_num)
121 return &d->column_descriptions[col_num];
125 * Format of the header of the index file of an osl table.
127 * Bytes 16-31 are currently unused.
129 * \sa enum index_column_desc_offsets, HASH_SIZE, osl_table_flags.
131 enum index_header_offsets {
132 /** Bytes 0-8: PARASLASH. */
134 /** Byte 9: Dirty flag (nonzero if table is mapped). */
136 /** Byte 10: osl table version number. */
138 /** Byte 11: Table flags.*/
139 IDX_TABLE_FLAGS = 11,
140 /** Byte 12,13: Number of columns. */
142 /** Byte 14,15 Size of the index header. */
143 IDX_HEADER_SIZE = 14,
144 /** Column descriptions start here. */
145 IDX_COLUMN_DESCRIPTIONS = 32
149 * Format of the column description in the index header.
151 * \sa index_header_offsets.
153 enum index_column_desc_offsets {
154 /** Bytes 0,1: Storage_type. */
155 IDX_CD_STORAGE_TYPE = 0,
156 /** Bytes 2,3: Storage_flags. */
157 IDX_CD_STORAGE_FLAGS = 2,
158 /** Bytes 4 - 7: Data_size (only used for fixed size columns). */
159 IDX_CD_DATA_SIZE = 4,
160 /** Bytes 8 - ... Name of the column. */
164 /** Magic string contained in the header of the index file of each osl table. */
165 #define PARA_MAGIC "PARASLASH"
168 * The minimal number of bytes for a column in the index header.
170 * The column name starts at byte IDX_CD_NAME and must at least contain one
171 * character, plus the terminating NULL byte.
173 #define MIN_IDX_COLUMN_DESCRIPTION_SIZE (IDX_CD_NAME + 2)
176 * Get the number of bytes used for a column in the index header.
178 * \param name The name of the column.
180 * The amount of space used for a column in the index header of a table depends
181 * on the (length of the) name of the column.
183 * \return The total number of bytes needed to store one column of this name.
185 _static_inline_ size_t index_column_description_size(const char *name)
187 return MIN_IDX_COLUMN_DESCRIPTION_SIZE + strlen(name) - 1;
190 #define CURRENT_TABLE_VERSION 1
191 #define MIN_TABLE_VERSION 1
192 #define MAX_TABLE_VERSION 1
193 /** An index header must be at least that many bytes long. */
194 #define MIN_INDEX_HEADER_SIZE(num_cols) (MIN_IDX_COLUMN_DESCRIPTION_SIZE \
195 * num_cols + IDX_COLUMN_DESCRIPTIONS)
198 * Get the number of rows from the size of the memory mapping.
200 * \param t Pointer to an open table.
202 * \return The number of rows, including invalid rows.
204 _static_inline_ unsigned table_num_rows(const struct osl_table *t)
206 return (t->index_map.size - t->index_header_size)
211 * Get the path of the index file from a table description.
213 * \param d The table description.
215 * \return The full path of the index file. Result must be freed by
218 _static_inline_ char *index_filename(const struct osl_table_description *d)
220 return make_message("%s/%s/index", d->dir, d->name);
224 * Get the path of storage of a column.
226 * \param t Pointer to an initialized table.
227 * \param col_num The number of the column to get the path for.
229 * \return The full path of the mapped data file (mapped storage) or the
230 * data directory (disk storage). Result must be freed by the caller.
232 * \sa osl_storage_type.
234 _static_inline_ char *column_filename(const struct osl_table *t, unsigned col_num)
236 char asc[2 * HASH_SIZE + 1];
237 hash_to_asc(t->columns[col_num].name_hash, asc);
238 return make_message("%s/%s/%s", t->desc->dir, t->desc->name, asc);
242 * Get the start of an index entry
244 * \param t Pointer to a table which has been mapped.
245 * \param row_num The number of the row whose index entry should be retrieved.
246 * \param row_index Result pointer.
248 * \return Positive on success, \p -E_INDEX_CORRUPTION otherwise.
250 * \sa get_cell_index().
252 _static_inline_ int get_row_index(const struct osl_table *t, uint32_t row_num,
255 uint32_t index_offset;
256 index_offset = t->index_header_size + t->row_index_size * row_num;
257 if (index_offset + 8 > t->index_map.size) {
259 return -E_INDEX_CORRUPTION;
261 *row_index = (char *)(t->index_map.data) + index_offset;
266 * Get the index entry of a row/column pair.
268 * \param t Pointer to a table which has been mapped.
269 * \param row_num The number of the row whose index entry should be retrieved.
270 * \param col_num The number of the column whose index entry should be retrieved.
271 * \param cell_index Result pointer.
273 * \return Positive on success, \p -E_INDEX_CORRUPTION otherwise.
275 * \sa get_row_index().
277 _static_inline_ int get_cell_index(const struct osl_table *t, uint32_t row_num,
278 uint32_t col_num, char **cell_index)
280 int ret = get_row_index(t, row_num, cell_index);
283 *cell_index += t->columns[col_num].index_offset;
288 * Change an index entry of a column after object was added.
290 * \param row_index Pointer to the index of the row to update.
291 * \param col Pointer to the column.
292 * \param map_size The new size of the data file.
293 * \param object_size The size of the object just appended to the data file.
295 * This is called right after an object was appended to the data file for a
298 * \sa get_row_index().
300 _static_inline_ void update_cell_index(char *row_index, struct osl_column *col,
301 uint32_t map_size, uint32_t object_size)
303 write_u32(row_index + col->index_offset, map_size - object_size - 1);
304 write_u32(row_index + col->index_offset + 4, object_size + 1);
308 * Get the full path of a disk storage object
310 * \param t Pointer to an initialized table.
311 * \param col_num The number of the column the disk storage object belongs to.
312 * \param ds_name The disk storage name of the object.
314 * \return Pointer to the full path which must be freed by the caller.
316 * \sa column_filename(), disk_storage_name_of_row().
318 _static_inline_ char *disk_storage_path(const struct osl_table *t,
319 unsigned col_num, const char *ds_name)
321 char *dirname = column_filename(t, col_num);
322 char *filename = make_message("%s/%s", dirname, ds_name);
328 * Get the column description of the next column of a given type.
330 * \param type the desired storage type.
331 * \param col_num the column to start the search.
332 * \param t the osl table.
333 * \param cd result is returned here.
335 * \return On success, \a cd contains the column description of the next column
336 * of type \a type, and the number of that column is returned. Otherwise, \a
337 * cd is set to \p NULL and the function returns t->num_columns + 1.
339 * \sa FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN, FOR_EACH_RBTREE_COLUMN,
340 * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN, osl_storage_type.
342 _static_inline_ int next_column_of_type(enum osl_storage_type type, int col_num,
343 const struct osl_table *t,
344 const struct osl_column_description **cd)
347 while (col_num < t->desc->num_columns) {
348 *cd = get_column_description(t->desc, col_num);
349 if ((*cd)->storage_type == type)
357 * Find the next column with an associated rbtree.
359 * \param col_num The column to start the search.
360 * \param t The osl table.
361 * \param cd Result is returned here.
363 * \return On success, \a cd contains the column description of the next column
364 * with associated rbtree, and the number of that column is returned.
365 * Otherwise, \a cd is set to \p NULL and the function returns t->num_columns +
368 * \sa FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN, FOR_EACH_RBTREE_COLUMN,
369 * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN, osl_storage_flags.
371 _static_inline_ int next_rbtree_column(int col_num, const struct osl_table *t,
372 const struct osl_column_description **cd)
375 while (col_num < t->desc->num_columns) {
376 *cd = get_column_description(t->desc, col_num);
377 if ((*cd)->storage_flags & OSL_RBTREE)
385 /* quite some dirty hacks */
387 /** Round up size of struct osl_row to multiple of 8 */
388 #define RB_NODES_OFFSET ((sizeof(struct osl_row) + 7) / 8 * 8)
391 * Allocate a new osl row.
393 * \param num_rbtrees The number of rbtrees for this row.
395 * \return A pointer to a zeroed-out area suitable for holding an osl row
396 * with \a num_rbtrees rbtree columns.
398 _static_inline_ struct osl_row *allocate_row(unsigned num_rbtrees)
400 size_t s = RB_NODES_OFFSET + num_rbtrees * sizeof(struct rb_node);
401 return para_calloc(s);
405 * Compute the pointer to a rbtree node embedded in a osl row.
407 * \param row The row to extract the rbtree pointer from.
408 * \param rbtree_num The number of the rbtree node to extract.
410 * \return A pointer to the \a rbtree_num th node contained in \a row.
412 _static_inline_ struct rb_node *get_rb_node_pointer(const struct osl_row *row, uint32_t rbtree_num)
414 return ((struct rb_node *)(((char *)row) + RB_NODES_OFFSET)) + rbtree_num;
418 * Get a pointer to the struct containing the given rbtree node.
420 * \param node Pointer to the rbtree node.
421 * \param rbtree_num Number of \a node in the array of rbtree nodes.
423 * \return A pointer to the row containing \a node.
425 _static_inline_ struct osl_row *get_row_pointer(const struct rb_node *node,
429 return (struct osl_row *)(((char *)node) - RB_NODES_OFFSET);
433 * Compute a cryptographic hash of an osl object.
435 * \param obj the Object to compute the hash value from.
436 * \param hash Result is returned here.
438 static inline void hash_object(const struct osl_object *obj, HASH_TYPE *hash)
440 return hash_function(obj->data, obj->size, hash);
444 * Get the relative path of an object, given the hash value.
446 * \param t Pointer to an initialized osl table.
447 * \param hash An arbitrary hash value.
449 * This function is typically called with \a hash being the hash of the object
450 * stored in the disk storage name column of a row. If the OSL_LARGE_TABLE
451 * flag is set, the first two hex digits get separated with a slash from the
454 * \return The relative path for all disk storage objects corresponding to \a
457 * \sa struct osl_table:disk_storage_name_column.
459 static inline char *disk_storage_name_of_hash(const struct osl_table *t, HASH_TYPE *hash)
461 char asc[2 * HASH_SIZE + 2];
463 hash_to_asc(hash, asc);
464 if (t->desc->flags & OSL_LARGE_TABLE)
465 return make_message("%.2s/%s", asc, asc + 2);
466 return para_strdup(asc);
470 * A wrapper for rename(2).
472 * \param old_path The source path.
473 * \param new_path The destination path.
475 * \return positive in success, \p -E_RENAME on errors.
479 static inline int para_rename(const char *old_path, const char *new_path)
481 if (rename(old_path, new_path) < 0)
487 * Iterate over each column of an initialized table.
489 * \param col A pointer to a struct osl_column.
490 * \param desc Pointer to the table description.
491 * \param cd Pointer to struct osl_column_description.
493 * On each iteration, \a col will point to the next column of the table and \a
494 * cd will point to the column description of this column.
496 * \sa struct osl_column FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
497 * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
498 * FOR_EACH_VOLATILE_COLUMN.
500 #define FOR_EACH_COLUMN(col, desc, cd) \
501 for (col = 0; col < (desc)->num_columns && \
502 (cd = get_column_description(desc, col)); col++)
505 * Iterate over each column with associated rbtree.
507 * \param col Same meaning as in FOR_EACH_COLUMN().
508 * \param table Same meaning as in FOR_EACH_COLUMN().
509 * \param cd Same meaning as in FOR_EACH_COLUMN().
511 * \sa osl_storage_flags::OSL_RBTREE, FOR_EACH_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
512 * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
513 * FOR_EACH_VOLATILE_COLUMN.
515 #define FOR_EACH_RBTREE_COLUMN(col, table, cd) \
516 for (col = next_rbtree_column(0, table, &cd); \
517 col < table->desc->num_columns; \
518 col = next_rbtree_column(++col, table, &cd))
521 * Iterate over each column of given storage type.
523 * \param type The osl_storage_type to iterate over.
524 * \param col Same meaning as in FOR_EACH_COLUMN().
525 * \param table Same meaning as in FOR_EACH_COLUMN().
526 * \param cd Same meaning as in FOR_EACH_COLUMN().
528 * \sa osl_storage_type, FOR_EACH_COLUMN, FOR_EACH_RBTREE_COLUMN,
529 * FOR_EACH_MAPPED_COLUMN, FOR_EACH_DISK_STORAGE_COLUMN,
530 * FOR_EACH_VOLATILE_COLUMN.
532 #define FOR_EACH_COLUMN_OF_TYPE(type, col, table, cd) \
533 for (col = next_column_of_type(type, 0, table, &cd); \
534 col < table->desc->num_columns; \
535 col = next_column_of_type(type, ++col, table, &cd))
538 * Iterate over each mapped column.
540 * \param col Same meaning as in FOR_EACH_COLUMN().
541 * \param table Same meaning as in FOR_EACH_COLUMN().
542 * \param cd Same meaning as in FOR_EACH_COLUMN().
544 * Just like FOR_EACH_COLUMN(), but skip columns which are
545 * not of type \p OSL_MAPPED_STORAGE.
547 * \sa osl_storage_flags::OSL_MAPPED_STORAGE, FOR_EACH_COLUMN,
548 * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE,
549 * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN.
551 #define FOR_EACH_MAPPED_COLUMN(col, table, cd) \
552 FOR_EACH_COLUMN_OF_TYPE(OSL_MAPPED_STORAGE, col, table, cd)
555 * Iterate over each disk storage column.
557 * \param col Same meaning as in FOR_EACH_COLUMN().
558 * \param table Same meaning as in FOR_EACH_COLUMN().
559 * \param cd Same meaning as in FOR_EACH_COLUMN().
561 * Just like FOR_EACH_COLUMN(), but skip columns which are
562 * not of type \p OSL_DISK_STORAGE.
564 * \sa osl_storage_flags::OSL_DISK_STORAGE, FOR_EACH_COLUMN,
565 * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN,
566 * FOR_EACH_VOLATILE_COLUMN.
568 #define FOR_EACH_DISK_STORAGE_COLUMN(col, table, cd) \
569 FOR_EACH_COLUMN_OF_TYPE(OSL_DISK_STORAGE, col, table, cd)
572 * Iterate over each volatile column.
574 * \param col Same meaning as in FOR_EACH_COLUMN().
575 * \param table Same meaning as in FOR_EACH_COLUMN().
576 * \param cd Same meaning as in FOR_EACH_COLUMN().
578 * Just like FOR_EACH_COLUMN(), but skip columns which are
579 * not of type \p OSL_NO_STORAGE.
581 * \sa osl_storage_flags::OSL_NO_STORAGE, FOR_EACH_COLUMN,
582 * FOR_EACH_RBTREE_COLUMN, FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN,
583 * FOR_EACH_DISK_STORAGE_COLUMN.
585 #define FOR_EACH_VOLATILE_COLUMN(col, table, cd) \
586 FOR_EACH_COLUMN_OF_TYPE(OSL_NO_STORAGE, col, table, cd)