osl.c

   1 /*
   2  * Copyright (C) 2007-2009 Andre Noll <maan@tuebingen.mpg.de>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file osl.c Object storage layer functions. */
   8 #include <dirent.h> /* readdir() */
   9 #include <assert.h>
  10
  11 #include "log.h"
  12 #include "osl.h"
  13 #include "util.h"
  14 #include "osl_core.h"
  15
  16 /*
  17  * Taken from Drepper: How to write shared libraries, Appendix B.
  18  *
  19  * The main reason for this rather fancy implementation of strerror() is to
  20  * avoid having an array of pointers. This is desirable because initialized
  21  * pointer variables increase the startup time of the library due to the
  22  * processing of relocations.
  23  */
  24 #include <stddef.h>
  25 #define MSGSTRFIELD(line) MSGSTRFIELD1(line)
  26 #define MSGSTRFIELD1(line) str##line
  27 static const union msgstr_t {
  28         struct {
  29 #define OSL_ERROR(n, s) char MSGSTRFIELD(__LINE__)[sizeof(s)];
  30 #include "errtab.h"
  31 #undef OSL_ERROR
  32         };
  33         char str[0];
  34 } msgstr = { {
  35 #define OSL_ERROR(n, s) s,
  36 #include "errtab.h"
  37 #undef OSL_ERROR
  38 } };
  39 static const unsigned int errmsgidx[] = {
  40 #define OSL_ERROR(n, s) [n] = offsetof(union msgstr_t, MSGSTRFIELD(__LINE__)),
  41 #include "errtab.h"
  42 #undef OSL_ERROR
  43 };
  44
  45 __export const char *osl_strerror(int num)
  46 {
  47         return msgstr.str + errmsgidx[num];
  48 }
  49
  50 int loglevel = 0;
  51
  52 static void __attribute ((constructor)) init_loglevel(void)
  53 {
  54         char *p = getenv("OSL_LOGLEVEL");
  55
  56         /* don't log anything if unset */
  57         loglevel = p? atoi(p) : EMERG + 1;
  58 }
  59
  60 /**
  61  * The log function.
  62  *
  63  * \param ll Loglevel.
  64  * \param fmt Usual format string.
  65  *
  66  * All XXX_LOG() macros use this function.
  67  */
  68 __printf_2_3 void __log(int ll, const char* fmt,...)
  69 {
  70         va_list argp;
  71         struct tm *tm;
  72         time_t t1;
  73         char str[255] = "";
  74
  75         if (ll < loglevel)
  76                 return;
  77         time(&t1);
  78         tm = localtime(&t1);
  79         strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
  80         fprintf(stderr, "%s ", str);
  81         va_start(argp, fmt);
  82         vfprintf(stderr, fmt, argp);
  83         va_end(argp);
  84 }
  85
  86 /**
  87  * A wrapper for lseek(2).
  88  *
  89  * \param fd The file descriptor whose offset is to be to repositioned.
  90  * \param offset A value-result parameter.
  91  * \param whence Usual repositioning directive.
  92  *
  93  * Reposition the offset of the file descriptor \a fd to the argument \a offset
  94  * according to the directive \a whence. Upon successful return, \a offset
  95  * contains the resulting offset location as measured in bytes from the
  96  * beginning of the file.
  97  *
  98  * \return Positive on success. Otherwise, the function returns \p -E_OSL_LSEEK.
  99  *
 100  * \sa lseek(2).
 101  */
 102 static int __lseek(int fd, off_t *offset, int whence)
 103 {
 104         *offset = lseek(fd, *offset, whence);
 105         int ret = -E_OSL_LSEEK;
 106         if (*offset == -1)
 107                 return ret;
 108         return 1;
 109 }
 110
 111 static int append_file(const char *filename, char *data, size_t data_size,
 112                 uint32_t *new_pos)
 113 {
 114         int ret, fd;
 115
 116 //      DEBUG_LOG("appending %zu  + %zu bytes\n", header_size, data_size);
 117         ret = osl_open(filename, O_WRONLY | O_CREAT | O_APPEND, 0644);
 118         if (ret < 0)
 119                 return ret;
 120         fd = ret;
 121         ret = write_all(fd, data, &data_size);
 122         if (ret < 0)
 123                 goto out;
 124         if (new_pos) {
 125                 off_t offset = 0;
 126                 ret = __lseek(fd, &offset, SEEK_END);
 127                 if (ret < 0)
 128                         goto out;
 129 //              DEBUG_LOG("new file size: " FMT_OFF_T "\n", offset);
 130                 *new_pos = offset;
 131         }
 132         ret = 1;
 133 out:
 134         close(fd);
 135         return ret;
 136 }
 137
 138 static int verify_name(const char *name)
 139 {
 140         if (!name)
 141                 return -E_OSL_BAD_NAME;
 142         if (!*name)
 143                 return -E_OSL_BAD_NAME;
 144         if (strchr(name, '/'))
 145                 return -E_OSL_BAD_NAME;
 146         if (!strcmp(name, ".."))
 147                 return -E_OSL_BAD_NAME;
 148         if (!strcmp(name, "."))
 149                 return -E_OSL_BAD_NAME;
 150         return 1;
 151 }
 152
 153 static char *disk_storage_dirname(const struct osl_table *t, unsigned col_num,
 154                 const char *ds_name)
 155 {
 156         char *dirname, *column_name = column_filename(t, col_num);
 157
 158         if (!column_name)
 159                 return NULL;
 160         if (!(t->desc->flags & OSL_LARGE_TABLE))
 161                 return column_name;
 162         dirname = make_message("%s/%.2s", column_name, ds_name);
 163         free(column_name);
 164         return dirname;
 165 }
 166
 167 static char *disk_storage_name_of_object(const struct osl_table *t,
 168         const struct osl_object *obj)
 169 {
 170         HASH_TYPE hash[HASH_SIZE];
 171         hash_object(obj, hash);
 172         return disk_storage_name_of_hash(t, hash);
 173 }
 174
 175 static int disk_storage_name_of_row(const struct osl_table *t,
 176                 const struct osl_row *row, char **name)
 177 {
 178         struct osl_object obj;
 179         int ret = osl_get_object(t, row, t->disk_storage_name_column, &obj);
 180
 181         if (ret < 0)
 182                 return ret;
 183         *name = disk_storage_name_of_object(t, &obj);
 184         if (*name)
 185                 return 1;
 186         return -E_OSL_NOMEM;
 187 }
 188
 189 static void column_name_hash(const char *col_name, HASH_TYPE *hash)
 190 {
 191         hash_function(col_name, strlen(col_name), hash);
 192 }
 193
 194 static int init_column_descriptions(struct osl_table *t)
 195 {
 196         int i, j, ret;
 197         const struct osl_column_description *cd;
 198
 199         ret = verify_name(t->desc->name);
 200         if (ret < 0)
 201                 goto err;
 202         ret = -E_OSL_BAD_DB_DIR;
 203         if (!t->desc->dir && (t->num_disk_storage_columns || t->num_mapped_columns))
 204                 goto err;
 205         /* the size of the index header without column descriptions */
 206         t->index_header_size = IDX_COLUMN_DESCRIPTIONS;
 207         FOR_EACH_COLUMN(i, t->desc, cd) {
 208                 struct osl_column *col = t->columns + i;
 209                 if (cd->storage_flags & OSL_RBTREE) {
 210                         if (!cd->compare_function)
 211                                 return -E_OSL_NO_COMPARE_FUNC;
 212                 }
 213                 if (cd->storage_type == OSL_NO_STORAGE)
 214                         continue;
 215                 ret = -E_OSL_NO_COLUMN_NAME;
 216                 if (!cd->name || !cd->name[0])
 217                         goto err;
 218                 ret = verify_name(cd->name);
 219                 if (ret < 0)
 220                         goto err;
 221                 t->index_header_size += index_column_description_size(cd->name);
 222                 column_name_hash(cd->name, col->name_hash);
 223                 ret = -E_OSL_DUPLICATE_COL_NAME;
 224                 for (j = i + 1; j < t->desc->num_columns; j++) {
 225                         const char *name2 = get_column_description(t->desc,
 226                                 j)->name;
 227                         if (cd->name && name2 && !strcmp(cd->name, name2))
 228                                 goto err;
 229                 }
 230         }
 231         return 1;
 232 err:
 233         return ret;
 234 }
 235
 236 /**
 237  * Initialize a struct table from given table description.
 238  *
 239  * \param desc The description of the osl table.
 240  * \param table_ptr Result is returned here.
 241  *
 242  * This function performs several sanity checks on \p desc and returns if any
 243  * of these tests fail. On success, a struct \p osl_table is allocated and
 244  * initialized with data derived from \p desc.
 245  *
 246  * \return Standard.
 247  *
 248  * \sa struct osl_table.
 249  */
 250 int init_table_structure(const struct osl_table_description *desc,
 251                 struct osl_table **table_ptr)
 252 {
 253         const struct osl_column_description *cd;
 254         struct osl_table *t = calloc(1, sizeof(*t));
 255         int i, ret = -E_OSL_NOMEM, have_disk_storage_name_column = 0;
 256
 257         if (!t)
 258                 return ret;
 259         ret = -E_OSL_BAD_TABLE_DESC;
 260         if (!desc)
 261                 goto err;
 262         DEBUG_LOG("creating table structure for '%s' from table "
 263                 "description\n", desc->name);
 264         ret = -E_OSL_NO_COLUMN_DESC;
 265         if (!desc->column_descriptions)
 266                 goto err;
 267         ret = -E_OSL_NO_COLUMNS;
 268         if (!desc->num_columns)
 269                 goto err;
 270         ret = -E_OSL_NOMEM;
 271         t->columns = calloc(desc->num_columns, sizeof(struct osl_column));
 272         if (!t->columns)
 273                 goto err;
 274         t->desc = desc;
 275         FOR_EACH_COLUMN(i, t->desc, cd) {
 276                 enum osl_storage_type st = cd->storage_type;
 277                 enum osl_storage_flags sf = cd->storage_flags;
 278                 struct osl_column *col = &t->columns[i];
 279
 280                 ret = -E_OSL_BAD_STORAGE_TYPE;
 281                 if (st != OSL_MAPPED_STORAGE && st != OSL_DISK_STORAGE
 282                                 && st != OSL_NO_STORAGE)
 283                         goto err;
 284                 ret = -E_OSL_BAD_STORAGE_FLAGS;
 285                 if (st == OSL_DISK_STORAGE && sf & OSL_RBTREE)
 286                         goto err;
 287                 if ((sf & OSL_RBTREE) && !(sf & OSL_UNIQUE))
 288                         WARNING_LOG("invalid storage flags for column %s: "
 289                                 "OSL_RBTREE && !OSL_UNIQUE\n", cd->name);
 290                 ret = -E_OSL_BAD_STORAGE_SIZE;
 291                 if (sf & OSL_FIXED_SIZE && !cd->data_size)
 292                         goto err;
 293                 switch (st) {
 294                 case OSL_DISK_STORAGE:
 295                         t->num_disk_storage_columns++;
 296                         break;
 297                 case OSL_MAPPED_STORAGE:
 298                         t->num_mapped_columns++;
 299                         col->index_offset = t->row_index_size;
 300                         t->row_index_size += 8;
 301                         break;
 302                 case OSL_NO_STORAGE:
 303                         col->volatile_num = t->num_volatile_columns;
 304                         t->num_volatile_columns++;
 305                         break;
 306                 }
 307                 if (sf & OSL_RBTREE) {
 308                         col->rbtree_num = t->num_rbtrees;
 309                         t->num_rbtrees++;
 310                         if ((sf & OSL_UNIQUE) && (st == OSL_MAPPED_STORAGE)) {
 311                                 if (!have_disk_storage_name_column)
 312                                         t->disk_storage_name_column = i;
 313                                 have_disk_storage_name_column = 1;
 314                         }
 315                 }
 316         }
 317         ret = -E_OSL_NO_UNIQUE_RBTREE_COLUMN;
 318         if (t->num_disk_storage_columns && !have_disk_storage_name_column)
 319                 goto err;
 320         ret = -E_OSL_NO_RBTREE_COL;
 321         if (!t->num_rbtrees)
 322                 goto err;
 323         /* success */
 324         DEBUG_LOG("OK. Index entry size: %u\n", t->row_index_size);
 325         ret = init_column_descriptions(t);
 326         if (ret < 0)
 327                 goto err;
 328         *table_ptr = t;
 329         return 1;
 330 err:
 331         free(t->columns);
 332         free(t);
 333         return ret;
 334 }
 335
 336 /**
 337  * Read the table description from index header.
 338  *
 339  * \param map The memory mapping of the index file.
 340  * \param desc The values found in the index header are returned here.
 341  *
 342  * Read the index header, check for the osl magic string and the table version
 343  * number.  Read all information stored in the index header into \a desc.
 344  *
 345  * \return Standard.
 346  *
 347  * \sa struct osl_table_description, osl_create_table.
 348  */
 349 int read_table_desc(struct osl_object *map, struct osl_table_description *desc)
 350 {
 351         char *buf = map->data;
 352         uint8_t table_version;
 353         uint16_t header_size;
 354         int ret, i;
 355         unsigned offset;
 356         struct osl_column_description *cd;
 357
 358         if (map->size < MIN_INDEX_HEADER_SIZE(1))
 359                 return -E_OSL_SHORT_TABLE;
 360         if (strncmp(buf + IDX_OSL_MAGIC, OSL_MAGIC, strlen(OSL_MAGIC)))
 361                 return -E_OSL_NO_MAGIC;
 362         table_version = read_u8(buf + IDX_VERSION);
 363         INFO_LOG("osl versions (table/min/current): %u/%u/%u\n",
 364                 table_version, MIN_TABLE_VERSION, CURRENT_TABLE_VERSION);
 365         if (table_version < MIN_TABLE_VERSION /* table too old */
 366                 || table_version > CURRENT_TABLE_VERSION) /* libosl too old */
 367                 return -E_OSL_VERSION_MISMATCH;
 368         desc->flags = read_u8(buf + IDX_TABLE_FLAGS);
 369         desc->num_columns = read_u16(buf + IDX_NUM_COLUMNS);
 370         INFO_LOG("%u columns\n", desc->num_columns);
 371         if (!desc->num_columns)
 372                 return -E_OSL_NO_COLUMNS;
 373         header_size = read_u16(buf + IDX_HEADER_SIZE);
 374         if (map->size < header_size)
 375                 return -E_OSL_BAD_SIZE;
 376         desc->column_descriptions = calloc(desc->num_columns,
 377                 sizeof(struct osl_column_description));
 378         if (!desc->column_descriptions)
 379                 return -E_OSL_NOMEM;
 380         offset = IDX_COLUMN_DESCRIPTIONS;
 381         FOR_EACH_COLUMN(i, desc, cd) {
 382                 char *null_byte;
 383
 384                 ret = -E_OSL_SHORT_TABLE;
 385                 if (map->size < offset + MIN_IDX_COLUMN_DESCRIPTION_SIZE) {
 386                         ERROR_LOG("map size = %zu < %u = offset + min desc size\n",
 387                                 map->size, offset + MIN_IDX_COLUMN_DESCRIPTION_SIZE);
 388                         goto err;
 389                 }
 390                 cd->storage_type = read_u16(buf + offset + IDX_CD_STORAGE_TYPE);
 391                 cd->storage_flags = read_u16(buf + offset +
 392                         IDX_CD_STORAGE_FLAGS);
 393                 cd->data_size = read_u32(buf + offset + IDX_CD_DATA_SIZE);
 394                 null_byte = memchr(buf + offset + IDX_CD_NAME, '\0',
 395                         map->size - offset - IDX_CD_NAME);
 396                 ret = -E_OSL_INDEX_CORRUPTION;
 397                 if (!null_byte)
 398                         goto err;
 399                 ret = -E_OSL_NOMEM;
 400                 cd->name = strdup(buf + offset + IDX_CD_NAME);
 401                 if (!cd->name)
 402                         goto err;
 403                 offset += index_column_description_size(cd->name);
 404         }
 405         if (offset != header_size) {
 406                 ret = -E_OSL_INDEX_CORRUPTION;
 407                 ERROR_LOG("real header size = %u != %u = stored header size\n",
 408                         offset, header_size);
 409                 goto err;
 410         }
 411         return 1;
 412 err:
 413         FOR_EACH_COLUMN(i, desc, cd)
 414                 free(cd->name);
 415         return ret;
 416 }
 417
 418 /*
 419  * check whether the table description given by \p t->desc matches the on-disk
 420  * table structure stored in the index of \a t.
 421  */
 422 static int compare_table_descriptions(struct osl_table *t)
 423 {
 424         int i, ret;
 425         struct osl_table_description desc;
 426         const struct osl_column_description *cd1, *cd2;
 427
 428         /* read the on-disk structure into desc */
 429         ret = read_table_desc(&t->index_map, &desc);
 430         if (ret < 0)
 431                 return ret;
 432         ret = -E_OSL_BAD_TABLE_FLAGS;
 433         if (desc.flags != t->desc->flags)
 434                 goto out;
 435         ret = -E_OSL_BAD_COLUMN_NUM;
 436         if (desc.num_columns > t->desc->num_columns)
 437                 goto out;
 438         if (desc.num_columns < t->desc->num_columns) {
 439                 struct osl_column_description *cd;
 440                 unsigned diff = t->desc->num_columns - desc.num_columns;
 441                 INFO_LOG("extending table by %u volatile columns\n", diff);
 442                 ret = -E_OSL_NOMEM;
 443                 desc.column_descriptions = realloc(desc.column_descriptions,
 444                         t->desc->num_columns * sizeof(struct osl_column_description));
 445                 if (!desc.column_descriptions)
 446                         goto out;
 447                 for (i = desc.num_columns; i < t->desc->num_columns; i++) {
 448                         cd = get_column_description(&desc, i);
 449                         cd->storage_type = OSL_NO_STORAGE;
 450                         cd->name = NULL;
 451                 }
 452                 desc.num_columns += diff;
 453         }
 454         FOR_EACH_COLUMN(i, t->desc, cd1) {
 455                 cd2 = get_column_description(&desc, i);
 456                 ret = -E_OSL_BAD_STORAGE_TYPE;
 457                 if (cd1->storage_type != cd2->storage_type)
 458                         goto out;
 459                 if (cd1->storage_type == OSL_NO_STORAGE)
 460                         continue;
 461                 ret = -E_OSL_BAD_STORAGE_FLAGS;
 462                 if (cd1->storage_flags != cd2->storage_flags) {
 463                         ERROR_LOG("sf1 = %u != %u = sf2\n",
 464                                 cd1->storage_flags, cd2->storage_flags);
 465                         goto out;
 466                 }
 467                 ret = -E_OSL_BAD_DATA_SIZE;
 468                 if (cd1->storage_flags & OSL_FIXED_SIZE)
 469                         if (cd1->data_size != cd2->data_size)
 470                                 goto out;
 471                 ret = -E_OSL_BAD_COLUMN_NAME;
 472                 if (strcmp(cd1->name, cd2->name))
 473                         goto out;
 474         }
 475         INFO_LOG("table description of '%s' matches on-disk data, good\n",
 476                 t->desc->name);
 477         ret = 1;
 478 out:
 479         FOR_EACH_COLUMN(i, &desc, cd1)
 480                 free(cd1->name);
 481         free(desc.column_descriptions);
 482         return ret;
 483 }
 484
 485 static int create_table_index(struct osl_table *t)
 486 {
 487         char *buf, *filename;
 488         int i, ret;
 489         size_t size = t->index_header_size;
 490         const struct osl_column_description *cd;
 491         unsigned offset;
 492
 493         INFO_LOG("creating %zu byte index for table %s\n", size,
 494                 t->desc->name);
 495         buf = calloc(1, size);
 496         if (!buf)
 497                 return -E_OSL_NOMEM;
 498         sprintf(buf + IDX_OSL_MAGIC, "%s", OSL_MAGIC);
 499         write_u8(buf + IDX_TABLE_FLAGS, t->desc->flags);
 500         write_u8(buf + IDX_DIRTY_FLAG, 0);
 501         write_u8(buf + IDX_VERSION, CURRENT_TABLE_VERSION);
 502         write_u16(buf + IDX_NUM_COLUMNS, t->num_mapped_columns + t->num_disk_storage_columns);
 503         write_u16(buf + IDX_HEADER_SIZE, t->index_header_size);
 504         offset = IDX_COLUMN_DESCRIPTIONS;
 505         FOR_EACH_COLUMN(i, t->desc, cd) {
 506                 /* no need to store info about volatile storage */
 507                 if (cd->storage_type == OSL_NO_STORAGE)
 508                         continue;
 509                 write_u16(buf + offset + IDX_CD_STORAGE_TYPE,
 510                         cd->storage_type);
 511                 write_u16(buf + offset + IDX_CD_STORAGE_FLAGS,
 512                         cd->storage_flags);
 513                 if (cd->storage_flags & OSL_FIXED_SIZE)
 514                         write_u32(buf + offset + IDX_CD_DATA_SIZE,
 515                                 cd->data_size);
 516                 strcpy(buf + offset + IDX_CD_NAME, cd->name);
 517                 offset += index_column_description_size(cd->name);
 518         }
 519         assert(offset == size);
 520         filename = index_filename(t->desc);
 521         if (filename)
 522                 ret = write_file(filename, buf, size);
 523         else
 524                 ret = -E_OSL_NOMEM;
 525         free(buf);
 526         free(filename);
 527         return ret;
 528 }
 529
 530 __export int osl_create_table(const struct osl_table_description *desc)
 531 {
 532         const struct osl_column_description *cd;
 533         char *table_dir = NULL, *filename;
 534         struct osl_table *t;
 535         int i, ret = init_table_structure(desc, &t);
 536
 537         if (ret < 0)
 538                 return ret;
 539         INFO_LOG("creating %s\n", desc->name);
 540         FOR_EACH_COLUMN(i, t->desc, cd) {
 541                 if (cd->storage_type == OSL_NO_STORAGE)
 542                         continue;
 543                 if (!table_dir) {
 544                         ret = osl_mkdir(desc->dir, 0777);
 545                         if (ret < 0 && ret != -E_OSL_DIR_EXISTS)
 546                                 goto out;
 547                         table_dir = make_message("%s/%s", desc->dir,
 548                                 desc->name);
 549                         ret = -E_OSL_NOMEM;
 550                         if (!table_dir)
 551                                 goto out;
 552                         ret = osl_mkdir(table_dir, 0777);
 553                         if (ret < 0)
 554                                 goto out;
 555                 }
 556                 ret = -E_OSL_NOMEM;
 557                 filename = column_filename(t, i);
 558                 if (!filename)
 559                         goto out;
 560                 INFO_LOG("filename: %s\n", filename);
 561                 if (cd->storage_type == OSL_MAPPED_STORAGE) {
 562                         ret = osl_open(filename, O_RDWR | O_CREAT | O_EXCL,
 563                                 0644);
 564                         free(filename);
 565                         if (ret < 0)
 566                                 goto out;
 567                         close(ret);
 568                         continue;
 569                 }
 570                 /* DISK STORAGE */
 571                 ret = osl_mkdir(filename, 0777);
 572                 free(filename);
 573                 if (ret < 0)
 574                         goto out;
 575         }
 576         if (t->num_mapped_columns) {
 577                 ret = create_table_index(t);
 578                 if (ret < 0)
 579                         goto out;
 580         }
 581         ret = 1;
 582 out:
 583         free(table_dir);
 584         free(t->columns);
 585         free(t);
 586         return ret;
 587 }
 588
 589 static int table_is_dirty(struct osl_table *t)
 590 {
 591         char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
 592         uint8_t dirty = read_u8(buf) & 0x1;
 593         return !!dirty;
 594 }
 595
 596 static void mark_table_dirty(struct osl_table *t)
 597 {
 598         char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
 599         write_u8(buf, read_u8(buf) | 1);
 600 }
 601
 602 static void mark_table_clean(struct osl_table *t)
 603 {
 604         char *buf = (char *)t->index_map.data + IDX_DIRTY_FLAG;
 605         write_u8(buf, read_u8(buf) & 0xfe);
 606 }
 607
 608 static void unmap_column(struct osl_table *t, unsigned col_num)
 609 {
 610         struct osl_object map = t->columns[col_num].data_map;
 611         int ret;
 612         if (!map.data)
 613                 return;
 614         ret = osl_munmap(map.data, map.size);
 615         assert(ret > 0);
 616         map.data = NULL;
 617 }
 618
 619 /**
 620  * Unmap all mapped files of an osl table.
 621  *
 622  * \param t Pointer to a mapped table.
 623  * \param flags Options for unmapping.
 624  *
 625  * \return Positive on success, negative on errors.
 626  *
 627  * \sa map_table(), enum osl_close_flags, osl_munmap().
 628  */
 629 int unmap_table(struct osl_table *t, enum osl_close_flags flags)
 630 {
 631         unsigned i;
 632         const struct osl_column_description *cd;
 633         int ret;
 634
 635         if (!t->num_mapped_columns) /* can this ever happen? */
 636                 return 1;
 637         INFO_LOG("unmapping table '%s'\n", t->desc->name);
 638         if (!t->index_map.data)
 639                 return -E_OSL_NOT_MAPPED;
 640         if (flags & OSL_MARK_CLEAN)
 641                 mark_table_clean(t);
 642         ret = osl_munmap(t->index_map.data, t->index_map.size);
 643         if (ret < 0)
 644                 return ret;
 645         t->index_map.data = NULL;
 646         if (!t->num_rows)
 647                 return 1;
 648         FOR_EACH_MAPPED_COLUMN(i, t, cd)
 649                 unmap_column(t, i);
 650         return 1;
 651 }
 652
 653 static int map_column(struct osl_table *t, unsigned col_num)
 654 {
 655         struct stat statbuf;
 656         char *filename = column_filename(t, col_num);
 657         int ret;
 658
 659         if (!filename)
 660                 return -E_OSL_NOMEM;
 661         ret = osl_stat(filename, &statbuf);
 662         if (ret < 0) {
 663                 free(filename);
 664                 return ret;
 665         }
 666         if (!(S_IFREG & statbuf.st_mode)) {
 667                 free(filename);
 668                 return ret;
 669         }
 670         ret = mmap_full_file(filename, O_RDWR,
 671                 &t->columns[col_num].data_map.data,
 672                 &t->columns[col_num].data_map.size,
 673                 NULL);
 674         free(filename);
 675         return ret;
 676 }
 677
 678 /**
 679  * Map the index file and all columns of type \p OSL_MAPPED_STORAGE into memory.
 680  *
 681  * \param t Pointer to an initialized table structure.
 682  * \param flags Mapping options.
 683  *
 684  * \return Negative return value on errors; on success the number of rows
 685  * (including invalid rows) is returned.
 686  *
 687  * \sa unmap_table(), enum map_table_flags, osl_open_table(), mmap(2).
 688  */
 689 int map_table(struct osl_table *t, enum map_table_flags flags)
 690 {
 691         char *filename;
 692         const struct osl_column_description *cd;
 693         int i = 0, ret, num_rows = 0;
 694
 695         if (!t->num_mapped_columns)
 696                 return 0;
 697         if (t->index_map.data)
 698                 return -E_OSL_ALREADY_MAPPED;
 699         filename = index_filename(t->desc);
 700         if (!filename)
 701                 return -E_OSL_NOMEM;
 702         INFO_LOG("mapping table '%s' (index: %s)\n", t->desc->name, filename);
 703         ret = mmap_full_file(filename, flags & MAP_TBL_FL_MAP_RDONLY?
 704                 O_RDONLY : O_RDWR, &t->index_map.data, &t->index_map.size, NULL);
 705         free(filename);
 706         if (ret < 0)
 707                 return ret;
 708         if (flags & MAP_TBL_FL_VERIFY_INDEX) {
 709                 ret = compare_table_descriptions(t);
 710                 if (ret < 0)
 711                         goto err;
 712         }
 713         ret = -E_OSL_BUSY;
 714         if (!(flags & MAP_TBL_FL_IGNORE_DIRTY)) {
 715                 if (table_is_dirty(t)) {
 716                         ERROR_LOG("%s is dirty\n", t->desc->name);
 717                         goto err;
 718                 }
 719         }
 720         mark_table_dirty(t);
 721         num_rows = table_num_rows(t);
 722         if (!num_rows)
 723                 return num_rows;
 724         /* map data files */
 725         FOR_EACH_MAPPED_COLUMN(i, t, cd) {
 726                 ret = map_column(t, i);
 727                 if (ret < 0)
 728                         goto err;
 729         }
 730         return num_rows;
 731 err:    /* unmap what is already mapped */
 732         for (i--; i >= 0; i--) {
 733                 struct osl_object map = t->columns[i].data_map;
 734                 osl_munmap(map.data, map.size);
 735                 map.data = NULL;
 736         }
 737         osl_munmap(t->index_map.data, t->index_map.size);
 738         t->index_map.data = NULL;
 739         return ret;
 740 }
 741
 742 /**
 743  * Retrieve a mapped object by row and column number.
 744  *
 745  * \param t Pointer to an open osl table.
 746  * \param col_num Number of the mapped column containing the object to retrieve.
 747  * \param row_num Number of the row containing the object to retrieve.
 748  * \param obj The result is returned here.
 749  *
 750  * It is considered an error if \a col_num does not refer to a column
 751  * of storage type \p OSL_MAPPED_STORAGE.
 752  *
 753  * \return Standard.
 754  *
 755  * \sa osl_storage_type.
 756  */
 757 int get_mapped_object(const struct osl_table *t, unsigned col_num,
 758         uint32_t row_num, struct osl_object *obj)
 759 {
 760         struct osl_column *col = &t->columns[col_num];
 761         uint32_t offset;
 762         char *cell_index;
 763         int ret;
 764
 765         if (t->num_rows <= row_num)
 766                 return -E_OSL_BAD_ROW_NUM;
 767         ret = get_cell_index(t, row_num, col_num, &cell_index);
 768         if (ret < 0)
 769                 return ret;
 770         offset = read_u32(cell_index);
 771         obj->size = read_u32(cell_index + 4);
 772         obj->data = col->data_map.data + offset;
 773         return 1;
 774 }
 775
 776 /*
 777  * It's OK to call this with result = rb_node = NULL.  If result is not NULL,
 778  * and rb key was not found, result points to the parent node.
 779  */
 780 static int search_rbtree(const struct osl_object *obj,
 781                 const struct osl_table *t, unsigned col_num,
 782                 struct rb_node **result, struct rb_node ***rb_link)
 783 {
 784         struct osl_column *col = &t->columns[col_num];
 785         struct rb_node **new = &col->rbtree.rb_node, *parent = NULL;
 786         const struct osl_column_description *cd =
 787                 get_column_description(t->desc, col_num);
 788         enum osl_storage_type st = cd->storage_type;
 789         while (*new) {
 790                 struct osl_row *this_row = get_row_pointer(*new,
 791                         col->rbtree_num);
 792                 int ret;
 793                 struct osl_object this_obj;
 794                 parent = *new;
 795                 if (st == OSL_MAPPED_STORAGE) {
 796                         ret = get_mapped_object(t, col_num, this_row->num,
 797                                 &this_obj);
 798                         if (ret < 0)
 799                                 return ret;
 800                 } else
 801                         this_obj = this_row->volatile_objects[col->volatile_num];
 802                 ret = cd->compare_function(obj, &this_obj);
 803                 if (!ret) {
 804                         if (result)
 805                                 *result = get_rb_node_pointer(this_row,
 806                                         col->rbtree_num);
 807                         return 1;
 808                 }
 809                 if (ret < 0)
 810                         new = &((*new)->rb_left);
 811                 else
 812                         new = &((*new)->rb_right);
 813         }
 814         if (result)
 815                 *result = parent;
 816         if (rb_link)
 817                 *rb_link = new;
 818         return -E_OSL_RB_KEY_NOT_FOUND;
 819 }
 820
 821 static int insert_rbtree(struct osl_table *t, unsigned col_num,
 822         const struct osl_row *row, const struct osl_object *obj)
 823 {
 824         struct rb_node *parent, **rb_link;
 825         unsigned rbtree_num;
 826         struct rb_node *n;
 827         int ret = search_rbtree(obj, t, col_num, &parent, &rb_link);
 828
 829         if (ret > 0)
 830                 return -E_OSL_RB_KEY_EXISTS;
 831         rbtree_num = t->columns[col_num].rbtree_num;
 832         n = get_rb_node_pointer(row, rbtree_num);
 833         rb_link_node(n, parent, rb_link);
 834         rb_insert_color(n, &t->columns[col_num].rbtree);
 835         return 1;
 836 }
 837
 838 static void remove_rb_node(struct osl_table *t, unsigned col_num,
 839                 const struct osl_row *row)
 840 {
 841         struct osl_column *col = &t->columns[col_num];
 842         const struct osl_column_description *cd =
 843                 get_column_description(t->desc, col_num);
 844         enum osl_storage_flags sf = cd->storage_flags;
 845         struct rb_node *victim, *splice_out_node, *tmp;
 846         if (!(sf & OSL_RBTREE))
 847                 return;
 848         /*
 849          * Which node is removed/spliced out actually depends on how many
 850          * children the victim node has: If it has no children, it gets
 851          * deleted. If it has one child, it gets spliced out. If it has two
 852          * children, its successor (which has at most a right child) gets
 853          * spliced out.
 854          */
 855         victim = get_rb_node_pointer(row, col->rbtree_num);
 856         if (victim->rb_left && victim->rb_right)
 857                 splice_out_node = rb_next(victim);
 858         else
 859                 splice_out_node = victim;
 860         /* Go up to the root and decrement the size of each node in the path. */
 861         for (tmp = splice_out_node; tmp; tmp = rb_parent(tmp))
 862                 tmp->size--;
 863         rb_erase(victim, &col->rbtree);
 864 }
 865
 866 static int add_row_to_rbtrees(struct osl_table *t, uint32_t row_num,
 867                 struct osl_object *volatile_objs, struct osl_row **row_ptr)
 868 {
 869         unsigned i;
 870         int ret;
 871         struct osl_row *row = allocate_row(t->num_rbtrees);
 872         const struct osl_column_description *cd;
 873
 874         if (!row)
 875                 return -E_OSL_NOMEM;
 876         row->num = row_num;
 877         row->volatile_objects = volatile_objs;
 878         FOR_EACH_RBTREE_COLUMN(i, t, cd) {
 879                 if (cd->storage_type == OSL_MAPPED_STORAGE) {
 880                         struct osl_object obj;
 881                         ret = get_mapped_object(t, i, row_num, &obj);
 882                         if (ret < 0)
 883                                 goto err;
 884                         ret = insert_rbtree(t, i, row, &obj);
 885                 } else { /* volatile */
 886                         const struct osl_object *obj
 887                                 = volatile_objs + t->columns[i].volatile_num;
 888                         ret = insert_rbtree(t, i, row, obj);
 889                 }
 890                 if (ret < 0)
 891                         goto err;
 892         }
 893         if (row_ptr)
 894                 *row_ptr = row;
 895         return 1;
 896 err: /* rollback changes, i.e. remove added entries from rbtrees */
 897         while (i)
 898                 remove_rb_node(t, i--, row);
 899         free(row);
 900         return ret;
 901 }
 902
 903 static void free_volatile_objects(const struct osl_table *t,
 904                 enum osl_close_flags flags)
 905 {
 906         int i, j;
 907         struct rb_node *n;
 908         struct osl_column *rb_col;
 909         const struct osl_column_description *cd;
 910
 911         if (!t->num_volatile_columns)
 912                 return;
 913         /* find the first rbtree column (any will do) */
 914         FOR_EACH_RBTREE_COLUMN(i, t, cd)
 915                 break;
 916         rb_col = t->columns + i;
 917         /* walk that rbtree and free all volatile objects */
 918         for (n = rb_first(&rb_col->rbtree); n; n = rb_next(n)) {
 919                 struct osl_row *r = get_row_pointer(n, rb_col->rbtree_num);
 920                 if (flags & OSL_FREE_VOLATILE)
 921                         FOR_EACH_VOLATILE_COLUMN(j, t, cd) {
 922                                 if (cd->storage_flags & OSL_DONT_FREE)
 923                                         continue;
 924                                 free(r->volatile_objects[
 925                                         t->columns[j].volatile_num].data);
 926                         }
 927 //                      for (j = 0; j < t->num_volatile_columns; j++)
 928 //                              free(r->volatile_objects[j].data);
 929                 free(r->volatile_objects);
 930         }
 931 }
 932
 933 /**
 934  * Erase all rbtree nodes and free resources.
 935  *
 936  * \param t Pointer to an open osl table.
 937  *
 938  * This function is called by osl_close_table().
 939  */
 940 void clear_rbtrees(struct osl_table *t)
 941 {
 942         const struct osl_column_description *cd;
 943         unsigned i, rbtrees_cleared = 0;
 944
 945         FOR_EACH_RBTREE_COLUMN(i, t, cd) {
 946                 struct osl_column *col = &t->columns[i];
 947                 struct rb_node *n;
 948                 rbtrees_cleared++;
 949                 for (n = rb_first(&col->rbtree); n;) {
 950                         struct osl_row *r;
 951                         rb_erase(n, &col->rbtree);
 952                         if (rbtrees_cleared == t->num_rbtrees) {
 953                                 r = get_row_pointer(n, col->rbtree_num);
 954                                 n = rb_next(n);
 955                                 free(r);
 956                         } else
 957                                 n = rb_next(n);
 958                 }
 959         }
 960
 961 }
 962
 963 __export int osl_close_table(struct osl_table *t, enum osl_close_flags flags)
 964 {
 965         int ret;
 966
 967         if (!t)
 968                 return -E_OSL_BAD_TABLE;
 969         NOTICE_LOG("closing table %s\n", t->desc->name);
 970         free_volatile_objects(t, flags);
 971         clear_rbtrees(t);
 972         ret = unmap_table(t, flags);
 973         if (ret < 0)
 974                 ERROR_LOG("unmap_table failed: %d\n", ret);
 975         free(t->columns);
 976         free(t);
 977         return ret;
 978 }
 979
 980 /**
 981  * Find out whether the given row number corresponds to an invalid row.
 982  *
 983  * \param t Pointer to the osl table.
 984  * \param row_num The number of the row in question.
 985  *
 986  * By definition, a row is considered invalid if all its index entries
 987  * are invalid.
 988  *
 989  * \return Positive if \a row_num corresponds to an invalid row,
 990  * zero if it corresponds to a valid row, negative on errors.
 991  */
 992 int row_is_invalid(struct osl_table *t, uint32_t row_num)
 993 {
 994         char *row_index;
 995         int i, ret = get_row_index(t, row_num, &row_index);
 996
 997         if (ret < 0)
 998                 return ret;
 999         for (i = 0; i < t->row_index_size; i++) {
1000                 if ((unsigned char)row_index[i] != 0xff)
1001                         return 0;
1002         }
1003         INFO_LOG("row %d is invalid\n", row_num);
1004         return 1;
1005 }
1006
1007 /**
1008  * Invalidate a row of an osl table.
1009  *
1010  * \param t Pointer to an open osl table.
1011  * \param row_num Number of the row to mark as invalid.
1012  *
1013  * This function marks each mapped object in the index entry of \a row as
1014  * invalid.
1015  *
1016  * \return Standard.
1017  */
1018 int mark_row_invalid(struct osl_table *t, uint32_t row_num)
1019 {
1020         char *row_index;
1021         int ret = get_row_index(t, row_num, &row_index);
1022
1023         if (ret < 0)
1024                 return ret;
1025         INFO_LOG("marking row %d as invalid\n", row_num);
1026         memset(row_index, 0xff, t->row_index_size);
1027         return 1;
1028 }
1029
1030 /**
1031  * Initialize all rbtrees and compute number of invalid rows.
1032  *
1033  * \param t The table containing the rbtrees to be initialized.
1034  *
1035  * \return Standard.
1036  */
1037 int init_rbtrees(struct osl_table *t)
1038 {
1039         int i, ret;
1040         const struct osl_column_description *cd;
1041
1042         /* create rbtrees */
1043         FOR_EACH_RBTREE_COLUMN(i, t, cd)
1044                 t->columns[i].rbtree = RB_ROOT;
1045         /* add valid rows to rbtrees */
1046         t->num_invalid_rows = 0;
1047         for (i = 0; i < t->num_rows; i++) {
1048                 struct osl_object *volatile_objs;
1049                 ret = row_is_invalid(t, i);
1050                 if (ret < 0)
1051                         return ret;
1052                 if (ret) {
1053                         t->num_invalid_rows++;
1054                         continue;
1055                 }
1056                 if (t->num_volatile_columns > 0) {
1057                         volatile_objs = calloc(t->num_volatile_columns,
1058                                 sizeof(struct osl_object));
1059                         if (!volatile_objs)
1060                                 return -E_OSL_NOMEM;
1061                 } else
1062                         volatile_objs = NULL;
1063                 ret = add_row_to_rbtrees(t, i, volatile_objs, NULL);
1064                 if (ret < 0)
1065                         return ret;
1066         }
1067         return 1;
1068 }
1069
1070 __export int osl_open_table(const struct osl_table_description *table_desc,
1071                 struct osl_table **result)
1072 {
1073         int i, ret;
1074         struct osl_table *t;
1075         const struct osl_column_description *cd;
1076
1077         NOTICE_LOG("opening table %s\n", table_desc->name);
1078         ret = init_table_structure(table_desc, &t);
1079         if (ret < 0)
1080                 return ret;
1081         FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd) {
1082                 struct stat statbuf;
1083                 char *dirname = column_filename(t, i);
1084
1085                 ret = -E_OSL_NOMEM;
1086                 if (!dirname)
1087                         goto err;
1088                 /* check if directory exists */
1089                 ret = osl_stat(dirname, &statbuf);
1090                 free(dirname);
1091                 if (ret < 0)
1092                         goto err;
1093                 ret = -E_OSL_NOTDIR;
1094                 if (!S_ISDIR(statbuf.st_mode))
1095                         goto err;
1096         }
1097         ret = map_table(t, MAP_TBL_FL_VERIFY_INDEX);
1098         if (ret < 0)
1099                 goto err;
1100         t->num_rows = ret;
1101         DEBUG_LOG("num rows: %d\n", t->num_rows);
1102         ret = init_rbtrees(t);
1103         if (ret < 0) {
1104                 osl_close_table(t, OSL_MARK_CLEAN); /* ignore further errors */
1105                 return ret;
1106         }
1107         *result = t;
1108         return 1;
1109 err:
1110         free(t->columns);
1111         free(t);
1112         return ret;
1113 }
1114
1115 static int create_disk_storage_object_dir(const struct osl_table *t,
1116                 unsigned col_num, const char *ds_name)
1117 {
1118         char *dirname;
1119         int ret;
1120
1121         if (!(t->desc->flags & OSL_LARGE_TABLE))
1122                 return 1;
1123         dirname = disk_storage_dirname(t, col_num, ds_name);
1124         if (!dirname)
1125                 return -E_OSL_NOMEM;
1126         ret = osl_mkdir(dirname, 0777);
1127         free(dirname);
1128         if (ret < 0 && ret != -E_OSL_DIR_EXISTS)
1129                 return ret;
1130         return 1;
1131 }
1132
1133 static int write_disk_storage_file(const struct osl_table *t, unsigned col_num,
1134         const struct osl_object *obj, const char *ds_name)
1135 {
1136         int ret;
1137         char *filename;
1138
1139         ret = create_disk_storage_object_dir(t, col_num, ds_name);
1140         if (ret < 0)
1141                 return ret;
1142         filename = disk_storage_path(t, col_num, ds_name);
1143         if (!filename)
1144                 return -E_OSL_NOMEM;
1145         ret = write_file(filename, obj->data, obj->size);
1146         free(filename);
1147         return ret;
1148 }
1149
1150 static int append_map_file(const struct osl_table *t, unsigned col_num,
1151         const struct osl_object *obj, uint32_t *new_size)
1152 {
1153         char *filename = column_filename(t, col_num);
1154         int ret;
1155
1156         if (!filename)
1157                 return -E_OSL_NOMEM;
1158         ret = append_file(filename, obj->data, obj->size, new_size);
1159         free(filename);
1160         return ret;
1161 }
1162
1163 static int append_row_index(const struct osl_table *t, char *row_index)
1164 {
1165         char *filename;
1166         int ret;
1167
1168         if (!t->num_mapped_columns)
1169                 return 1;
1170         filename = index_filename(t->desc);
1171         if (!filename)
1172                 return -E_OSL_NOMEM;
1173         ret = append_file(filename, row_index, t->row_index_size, NULL);
1174         free(filename);
1175         return ret;
1176 }
1177
1178 static int truncate_mapped_file(const struct osl_table *t, unsigned col_num,
1179                 off_t size)
1180 {
1181         int ret;
1182         char *filename = column_filename(t, col_num);
1183
1184         if (!filename)
1185                 return -E_OSL_NOMEM;
1186         ret = truncate_file(filename, size);
1187         free(filename);
1188         return ret;
1189 }
1190
1191 static int delete_disk_storage_file(const struct osl_table *t, unsigned col_num,
1192                 const char *ds_name)
1193 {
1194         char *dirname, *filename = disk_storage_path(t, col_num, ds_name);
1195         int ret = 1;
1196
1197         if (!filename)
1198                 return -E_OSL_NOMEM;
1199         if (unlink(filename) < 0)
1200                 ret = errno == ENOENT? -E_OSL_NOENT : -E_OSL_UNLINK;
1201         free(filename);
1202         if (ret < 0)
1203                 return ret;
1204         if (!(t->desc->flags & OSL_LARGE_TABLE))
1205                 return 1;
1206         dirname = disk_storage_dirname(t, col_num, ds_name);
1207         if (!dirname)
1208                 return -E_OSL_NOMEM;
1209         rmdir(dirname);
1210         free(dirname);
1211         return 1;
1212 }
1213
1214 __export int osl_add_and_get_row(struct osl_table *t, struct osl_object *objects,
1215                 struct osl_row **row)
1216 {
1217         int i, ret;
1218         char *ds_name = NULL;
1219         struct rb_node **rb_parents = NULL, ***rb_links = NULL;
1220         char *new_row_index = NULL;
1221         struct osl_object *volatile_objs = NULL;
1222         const struct osl_column_description *cd;
1223
1224         if (!t)
1225                 return -E_OSL_BAD_TABLE;
1226         rb_parents = malloc(t->num_rbtrees * sizeof(struct rn_node*));
1227         if (!rb_parents)
1228                 return -E_OSL_NOMEM;
1229         rb_links = malloc(t->num_rbtrees * sizeof(struct rn_node**));
1230         if (!rb_links) {
1231                 free(rb_parents);
1232                 return -E_OSL_NOMEM;
1233         }
1234         if (t->num_mapped_columns) {
1235                 new_row_index = malloc(t->row_index_size);
1236                 if (!new_row_index) {
1237                         free(rb_links);
1238                         free(rb_parents);
1239                         return -E_OSL_NOMEM;
1240                 }
1241         }
1242         /* pass 1: sanity checks */
1243 //      DEBUG_LOG("sanity tests: %p:%p\n", objects[0].data,
1244 //              objects[1].data);
1245         FOR_EACH_COLUMN(i, t->desc, cd) {
1246                 enum osl_storage_type st = cd->storage_type;
1247                 enum osl_storage_flags sf = cd->storage_flags;
1248
1249 //              ret = -E_OSL_NULL_OBJECT;
1250 //              if (!objects[i])
1251 //                      goto out;
1252                 if (st == OSL_DISK_STORAGE)
1253                         continue;
1254                 if (sf & OSL_RBTREE) {
1255                         unsigned rbtree_num = t->columns[i].rbtree_num;
1256                         ret = -E_OSL_RB_KEY_EXISTS;
1257 //                      DEBUG_LOG("checking whether %p exists\n",
1258 //                              objects[i].data);
1259                         if (search_rbtree(objects + i, t, i,
1260                                         &rb_parents[rbtree_num],
1261                                         &rb_links[rbtree_num]) > 0)
1262                                 goto out;
1263                 }
1264                 if (sf & OSL_FIXED_SIZE) {
1265 //                      DEBUG_LOG("fixed size. need: %zu, have: %d\n",
1266 //                              objects[i].size, cd->data_size);
1267                         ret = -E_OSL_BAD_DATA_SIZE;
1268                         if (objects[i].size != cd->data_size)
1269                                 goto out;
1270                 }
1271         }
1272         if (t->num_disk_storage_columns) {
1273                 ds_name = disk_storage_name_of_object(t,
1274                         &objects[t->disk_storage_name_column]);
1275                 ret = -E_OSL_NOMEM;
1276                 if (!ds_name)
1277                         goto out;
1278         }
1279         ret = unmap_table(t, OSL_MARK_CLEAN);
1280         if (ret < 0)
1281                 goto out;
1282 //      DEBUG_LOG("sanity tests passed%s\n", "");
1283         /* pass 2: create data files, append map data */
1284         FOR_EACH_COLUMN(i, t->desc, cd) {
1285                 enum osl_storage_type st = cd->storage_type;
1286                 if (st == OSL_NO_STORAGE)
1287                         continue;
1288                 if (st == OSL_MAPPED_STORAGE) {
1289                         uint32_t new_size;
1290                         struct osl_column *col = &t->columns[i];
1291 //                      DEBUG_LOG("appending object of size %zu\n",
1292 //                              objects[i].size);
1293                         ret = append_map_file(t, i, objects + i, &new_size);
1294                         if (ret < 0)
1295                                 goto rollback;
1296                         update_cell_index(new_row_index, col, new_size,
1297                                 objects[i].size);
1298                         continue;
1299                 }
1300                 /* DISK_STORAGE */
1301                 ret = write_disk_storage_file(t, i, objects + i, ds_name);
1302                 if (ret < 0)
1303                         goto rollback;
1304         }
1305         ret = append_row_index(t, new_row_index);
1306         if (ret < 0)
1307                 goto rollback;
1308         ret = map_table(t, MAP_TBL_FL_VERIFY_INDEX);
1309         if (ret < 0) { /* truncate index and rollback changes */
1310                 char *filename = index_filename(t->desc);
1311                 if (filename)
1312                         truncate_file(filename, t->row_index_size);
1313                 free(filename);
1314                 goto rollback;
1315         }
1316         /* pass 3: add entry to rbtrees */
1317         if (t->num_volatile_columns) {
1318                 ret = -E_OSL_NOMEM;
1319                 volatile_objs = calloc(t->num_volatile_columns,
1320                         sizeof(struct osl_object));
1321                 if (!volatile_objs)
1322                         goto out;
1323                 FOR_EACH_VOLATILE_COLUMN(i, t, cd)
1324                         volatile_objs[t->columns[i].volatile_num] = objects[i];
1325         }
1326         t->num_rows++;
1327 //      DEBUG_LOG("adding new entry as row #%d\n", t->num_rows - 1);
1328         ret = add_row_to_rbtrees(t, t->num_rows - 1, volatile_objs, row);
1329         if (ret < 0)
1330                 goto out;
1331 //      DEBUG_LOG("added new entry as row #%d\n", t->num_rows - 1);
1332         ret = 1;
1333         goto out;
1334 rollback: /* rollback all changes made, ignore further errors */
1335         for (i--; i >= 0; i--) {
1336                 cd = get_column_description(t->desc, i);
1337                 enum osl_storage_type st = cd->storage_type;
1338                 if (st == OSL_NO_STORAGE)
1339                         continue;
1340
1341                 if (st == OSL_MAPPED_STORAGE)
1342                         truncate_mapped_file(t, i, objects[i].size);
1343                 else /* disk storage */
1344                         delete_disk_storage_file(t, i, ds_name);
1345         }
1346         /* ignore error and return previous error value */
1347         map_table(t, MAP_TBL_FL_VERIFY_INDEX);
1348 out:
1349         free(new_row_index);
1350         free(ds_name);
1351         free(rb_parents);
1352         free(rb_links);
1353         return ret;
1354 }
1355
1356 __export int osl_add_row(struct osl_table *t, struct osl_object *objects)
1357 {
1358         return osl_add_and_get_row(t, objects, NULL);
1359 }
1360
1361 __export int osl_get_object(const struct osl_table *t, const struct osl_row *r,
1362         unsigned col_num, struct osl_object *object)
1363 {
1364         const struct osl_column_description *cd;
1365
1366         if (!t)
1367                 return -E_OSL_BAD_TABLE;
1368         cd = get_column_description(t->desc, col_num);
1369         /* col must not be disk storage */
1370         if (cd->storage_type == OSL_DISK_STORAGE)
1371                 return -E_OSL_BAD_STORAGE_TYPE;
1372         if (cd->storage_type == OSL_MAPPED_STORAGE)
1373                 return get_mapped_object(t, col_num, r->num, object);
1374         /* volatile */
1375         *object = r->volatile_objects[t->columns[col_num].volatile_num];
1376         return 1;
1377 }
1378
1379 __export int osl_del_row(struct osl_table *t, struct osl_row *row)
1380 {
1381         struct osl_row *r = row;
1382         int i, ret;
1383         const struct osl_column_description *cd;
1384
1385         if (!t)
1386                 return -E_OSL_BAD_TABLE;
1387         INFO_LOG("deleting row %p\n", row);
1388
1389         if (t->num_disk_storage_columns) {
1390                 char *ds_name;
1391                 ret = disk_storage_name_of_row(t, r, &ds_name);
1392                 if (ret < 0)
1393                         goto out;
1394                 FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd)
1395                         delete_disk_storage_file(t, i, ds_name);
1396                 free(ds_name);
1397         }
1398         FOR_EACH_COLUMN(i, t->desc, cd) {
1399                 struct osl_column *col = t->columns + i;
1400                 enum osl_storage_type st = cd->storage_type;
1401                 remove_rb_node(t, i, r);
1402                 if (st == OSL_MAPPED_STORAGE)
1403                         continue;
1404                 if (st == OSL_NO_STORAGE && !(cd->storage_flags & OSL_DONT_FREE))
1405                         free(r->volatile_objects[col->volatile_num].data);
1406         }
1407         if (t->num_mapped_columns) {
1408                 ret = mark_row_invalid(t, r->num);
1409                 if (ret < 0)
1410                         goto out;
1411                 t->num_invalid_rows++;
1412         } else
1413                 t->num_rows--;
1414         ret = 1;
1415 out:
1416         free(r->volatile_objects);
1417         free(r);
1418         return ret;
1419 }
1420
1421 /* test if column has an rbtree */
1422 static int check_rbtree_col(const struct osl_table *t, unsigned col_num,
1423                 struct osl_column **col)
1424 {
1425         if (!t)
1426                 return -E_OSL_BAD_TABLE;
1427         if (!(get_column_description(t->desc, col_num)->storage_flags & OSL_RBTREE))
1428                 return -E_OSL_BAD_STORAGE_FLAGS;
1429         *col = t->columns + col_num;
1430         return 1;
1431 }
1432
1433 __export int osl_get_row(const struct osl_table *t, unsigned col_num,
1434                 const struct osl_object *obj, struct osl_row **result)
1435 {
1436         int ret;
1437         struct rb_node *node;
1438         struct osl_row *row;
1439         struct osl_column *col;
1440
1441         *result = NULL;
1442         ret = check_rbtree_col(t, col_num, &col);
1443         if (ret < 0)
1444                 return ret;
1445         ret = search_rbtree(obj, t, col_num, &node, NULL);
1446         if (ret < 0)
1447                 return ret;
1448         row = get_row_pointer(node, t->columns[col_num].rbtree_num);
1449         *result = row;
1450         return 1;
1451 }
1452
1453 static int rbtree_loop(struct osl_column *col, void *private_data,
1454                 osl_rbtree_loop_func *func)
1455 {
1456         struct rb_node *n, *tmp;
1457
1458         /* this for-loop is safe against removal of an entry */
1459         for (n = rb_first(&col->rbtree), tmp = n? rb_next(n) : NULL;
1460                         n;
1461                         n = tmp, tmp = tmp? rb_next(tmp) : NULL) {
1462                 struct osl_row *r = get_row_pointer(n, col->rbtree_num);
1463                 if (func(r, private_data) < 0)
1464                         return -E_OSL_LOOP;
1465         }
1466         return 1;
1467 }
1468
1469 static int rbtree_loop_reverse(struct osl_column *col, void *private_data,
1470                 osl_rbtree_loop_func *func)
1471 {
1472         struct rb_node *n, *tmp;
1473
1474         /* safe against removal of an entry */
1475         for (n = rb_last(&col->rbtree), tmp = n? rb_prev(n) : NULL;
1476                         n;
1477                         n = tmp, tmp = tmp? rb_prev(tmp) : NULL) {
1478                 struct osl_row *r = get_row_pointer(n, col->rbtree_num);
1479                 if (func(r, private_data) < 0)
1480                         return -E_OSL_LOOP;
1481         }
1482         return 1;
1483 }
1484
1485 __export int osl_rbtree_loop(const struct osl_table *t, unsigned col_num,
1486         void *private_data, osl_rbtree_loop_func *func)
1487 {
1488         struct osl_column *col;
1489
1490         int ret = check_rbtree_col(t, col_num, &col);
1491         if (ret < 0)
1492                 return ret;
1493         return rbtree_loop(col, private_data, func);
1494 }
1495
1496 __export int osl_rbtree_loop_reverse(const struct osl_table *t, unsigned col_num,
1497         void *private_data, osl_rbtree_loop_func *func)
1498 {
1499         struct osl_column *col;
1500
1501         int ret = check_rbtree_col(t, col_num, &col);
1502         if (ret < 0)
1503                 return ret;
1504         return rbtree_loop_reverse(col, private_data, func);
1505 }
1506
1507 /* TODO: Rollback changes on errors */
1508 static int rename_disk_storage_objects(struct osl_table *t,
1509                 struct osl_object *old_obj, struct osl_object *new_obj)
1510 {
1511         int i, ret;
1512         const struct osl_column_description *cd;
1513         char *old_ds_name, *new_ds_name;
1514
1515         if (!t->num_disk_storage_columns)
1516                 return 1; /* nothing to do */
1517         if (old_obj->size == new_obj->size && !memcmp(new_obj->data,
1518                         old_obj->data, new_obj->size))
1519                 return 1; /* object did not change */
1520         old_ds_name = disk_storage_name_of_object(t, old_obj);
1521         new_ds_name = disk_storage_name_of_object(t, new_obj);
1522         ret = -E_OSL_NOMEM;
1523         if (!old_ds_name || ! new_ds_name)
1524                 goto out;
1525
1526         FOR_EACH_DISK_STORAGE_COLUMN(i, t, cd) {
1527                 char *old_filename, *new_filename;
1528                 ret = create_disk_storage_object_dir(t, i, new_ds_name);
1529                 if (ret < 0)
1530                         goto out;
1531                 old_filename = disk_storage_path(t, i, old_ds_name);
1532                 new_filename = disk_storage_path(t, i, new_ds_name);
1533                 if (!old_filename || !new_filename)
1534                         ret = -E_OSL_NOMEM;
1535                 else
1536                         ret = osl_rename(old_filename, new_filename);
1537                 free(old_filename);
1538                 free(new_filename);
1539                 if (ret < 0)
1540                         goto out;
1541         }
1542         ret = 1;
1543 out:
1544         free(old_ds_name);
1545         free(new_ds_name);
1546         return ret;
1547
1548 }
1549
1550 __export int osl_update_object(struct osl_table *t, const struct osl_row *r,
1551                 unsigned col_num, struct osl_object *obj)
1552 {
1553         struct osl_column *col;
1554         const struct osl_column_description *cd;
1555         int ret;
1556
1557         if (!t)
1558                 return -E_OSL_BAD_TABLE;
1559         col = &t->columns[col_num];
1560         cd = get_column_description(t->desc, col_num);
1561         DEBUG_LOG("updating column %u of %s\n", col_num, t->desc->name);
1562         if (cd->storage_flags & OSL_RBTREE) {
1563                 if (search_rbtree(obj, t, col_num, NULL, NULL) > 0)
1564                         return -E_OSL_RB_KEY_EXISTS;
1565         }
1566         if (cd->storage_flags & OSL_FIXED_SIZE) {
1567                 if (obj->size != cd->data_size)
1568                         return -E_OSL_BAD_DATA_SIZE;
1569         }
1570         remove_rb_node(t, col_num, r);
1571         if (cd->storage_type == OSL_NO_STORAGE) { /* TODO: If fixed size, reuse object? */
1572                 if (!(cd->storage_flags & OSL_DONT_FREE))
1573                         free(r->volatile_objects[col->volatile_num].data);
1574                 r->volatile_objects[col->volatile_num] = *obj;
1575         } else if (cd->storage_type == OSL_DISK_STORAGE) {
1576                 char *ds_name;
1577                 ret = disk_storage_name_of_row(t, r, &ds_name);
1578                 if (ret < 0)
1579                         return ret;
1580                 ret = delete_disk_storage_file(t, col_num, ds_name);
1581                 if (ret < 0 && ret != -E_OSL_NOENT) {
1582                         free(ds_name);
1583                         return ret;
1584                 }
1585                 ret = write_disk_storage_file(t, col_num, obj, ds_name);
1586                 free(ds_name);
1587                 if (ret < 0)
1588                         return ret;
1589         } else { /* mapped storage */
1590                 struct osl_object old_obj;
1591                 ret = get_mapped_object(t, col_num, r->num, &old_obj);
1592                 if (ret < 0)
1593                         return ret;
1594                 /*
1595                  * If the updated column is the disk storage name column, the
1596                  * disk storage name changes, so we have to rename all disk
1597                  * storage objects accordingly.
1598                  */
1599                 if (col_num == t->disk_storage_name_column) {
1600                         ret = rename_disk_storage_objects(t, &old_obj, obj);
1601                         if (ret < 0)
1602                                 return ret;
1603                 }
1604                 if (cd->storage_flags & OSL_FIXED_SIZE)
1605                         memcpy(old_obj.data, obj->data, cd->data_size);
1606                 else { /* TODO: if the size doesn't change, use old space */
1607                         uint32_t new_data_map_size;
1608                         char *row_index;
1609                         ret = get_row_index(t, r->num, &row_index);
1610                         if (ret < 0)
1611                                 return ret;
1612                         unmap_column(t, col_num);
1613                         ret = append_map_file(t, col_num, obj,
1614                                 &new_data_map_size);
1615                         if (ret < 0)
1616                                 return ret;
1617                         ret = map_column(t, col_num);
1618                         if (ret < 0)
1619                                 return ret;
1620                         update_cell_index(row_index, col, new_data_map_size,
1621                                 obj->size);
1622                 }
1623         }
1624         if (cd->storage_flags & OSL_RBTREE) {
1625                 ret = insert_rbtree(t, col_num, r, obj);
1626                 if (ret < 0)
1627                         return ret;
1628         }
1629         return 1;
1630 }
1631
1632 __export int osl_open_disk_object(const struct osl_table *t, const struct osl_row *r,
1633                 unsigned col_num, struct osl_object *obj)
1634 {
1635         const struct osl_column_description *cd;
1636         char *ds_name, *filename;
1637         int ret;
1638
1639         if (!t)
1640                 return -E_OSL_BAD_TABLE;
1641         cd = get_column_description(t->desc, col_num);
1642         if (cd->storage_type != OSL_DISK_STORAGE)
1643                 return -E_OSL_BAD_STORAGE_TYPE;
1644
1645         ret = disk_storage_name_of_row(t, r, &ds_name);
1646         if (ret < 0)
1647                 return ret;
1648         filename = disk_storage_path(t, col_num, ds_name);
1649         free(ds_name);
1650         if (!filename)
1651                 return -E_OSL_NOMEM;
1652         DEBUG_LOG("filename: %s\n", filename);
1653         ret = mmap_full_file(filename, O_RDONLY, &obj->data, &obj->size, NULL);
1654         free(filename);
1655         return ret;
1656 }
1657
1658 __export int osl_close_disk_object(struct osl_object *obj)
1659 {
1660         return osl_munmap(obj->data, obj->size);
1661 }
1662
1663 __export int osl_get_num_rows(const struct osl_table *t, unsigned *num_rows)
1664 {
1665         if (!t)
1666                 return -E_OSL_BAD_TABLE;
1667         assert(t->num_rows >= t->num_invalid_rows);
1668         *num_rows = t->num_rows - t->num_invalid_rows;
1669         return 1;
1670 }
1671
1672 __export int osl_get_rank(const struct osl_table *t, struct osl_row *r,
1673                 unsigned col_num, unsigned *rank)
1674 {
1675         struct osl_object obj;
1676         struct osl_column *col;
1677         struct rb_node *node;
1678         int ret = check_rbtree_col(t, col_num, &col);
1679
1680         if (ret < 0)
1681                 return ret;
1682         ret = osl_get_object(t, r, col_num, &obj);
1683         if (ret < 0)
1684                 return ret;
1685         ret = search_rbtree(&obj, t, col_num, &node, NULL);
1686         if (ret < 0)
1687                 return ret;
1688         ret = rb_rank(node, rank);
1689         if (ret < 0)
1690                 return -E_OSL_BAD_ROW;
1691         return 1;
1692 }
1693
1694 __export int osl_get_nth_row(const struct osl_table *t, unsigned col_num,
1695                 unsigned n, struct osl_row **result)
1696 {
1697         struct osl_column *col;
1698         struct rb_node *node;
1699         unsigned num_rows;
1700         int ret;
1701
1702         *result = NULL;
1703         if (n == 0)
1704                 return -E_OSL_RB_KEY_NOT_FOUND;
1705         ret = osl_get_num_rows(t, &num_rows);
1706         if (ret < 0)
1707                 return ret;
1708         if (n > num_rows)
1709                 return -E_OSL_RB_KEY_NOT_FOUND;
1710         ret = check_rbtree_col(t, col_num, &col);
1711         if (ret < 0)
1712                 return ret;
1713         node = rb_nth(col->rbtree.rb_node, n);
1714         if (!node)
1715                 return -E_OSL_RB_KEY_NOT_FOUND;
1716         *result = get_row_pointer(node, col->rbtree_num);
1717         return 1;
1718 }
1719
1720 __export int osl_rbtree_first_row(const struct osl_table *t, unsigned col_num,
1721                 struct osl_row **result)
1722 {
1723         return osl_get_nth_row(t, col_num, 1, result);
1724 }
1725
1726 __export int osl_rbtree_last_row(const struct osl_table *t, unsigned col_num,
1727                 struct osl_row **result)
1728 {
1729         unsigned num_rows;
1730         int ret = osl_get_num_rows(t, &num_rows);
1731
1732         if (ret < 0)
1733                 return ret;
1734         return osl_get_nth_row(t, col_num, num_rows, result);
1735 }