src/test_fs.c

   1 /*
   2 ** 2013 Jan 11
   3 **
   4 ** The author disclaims copyright to this source code.  In place of
   5 ** a legal notice, here is a blessing:
   6 **
   7 **    May you do good and not evil.
   8 **    May you find forgiveness for yourself and forgive others.
   9 **    May you share freely, never taking more than you give.
  10 **
  11 *************************************************************************
  12 ** Code for testing the virtual table interfaces.  This code
  13 ** is not included in the SQLite library.  It is used for automated
  14 ** testing of the SQLite library.
  15 **
  16 ** The FS virtual table is created as follows:
  17 **
  18 **   CREATE VIRTUAL TABLE tbl USING fs(idx);
  19 **
  20 ** where idx is the name of a table in the db with 2 columns.  The virtual
  21 ** table also has two columns - file path and file contents.
  22 **
  23 ** The first column of table idx must be an IPK, and the second contains file
  24 ** paths. For example:
  25 **
  26 **   CREATE TABLE idx(id INTEGER PRIMARY KEY, path TEXT);
  27 **   INSERT INTO idx VALUES(4, '/etc/passwd');
  28 **
  29 ** Adding the row to the idx table automatically creates a row in the
  30 ** virtual table with rowid=4, path=/etc/passwd and a text field that
  31 ** contains data read from file /etc/passwd on disk.
  32 **
  33 *************************************************************************
  34 ** Virtual table module "fsdir"
  35 **
  36 ** This module is designed to be used as a read-only eponymous virtual table.
  37 ** Its schema is as follows:
  38 **
  39 **   CREATE TABLE fsdir(dir TEXT, name TEXT);
  40 **
  41 ** When queried, a WHERE term of the form "dir = $dir" must be provided. The
  42 ** virtual table then appears to have one row for each entry in file-system
  43 ** directory $dir. Column dir contains a copy of $dir, and column "name"
  44 ** contains the name of the directory entry.
  45 **
  46 ** If the specified $dir cannot be opened or is not a directory, it is not
  47 ** an error. The virtual table appears to be empty in this case.
  48 **
  49 *************************************************************************
  50 ** Virtual table module "fstree"
  51 **
  52 ** This module is also a read-only eponymous virtual table with the
  53 ** following schema:
  54 **
  55 **   CREATE TABLE fstree(path TEXT, size INT, data BLOB);
  56 **
  57 ** Running a "SELECT * FROM fstree" query on this table returns the entire
  58 ** contents of the file-system, starting at "/". To restrict the search
  59 ** space, the virtual table supports LIKE and GLOB constraints on the
  60 ** 'path' column. For example:
  61 **
  62 **   SELECT * FROM fstree WHERE path LIKE '/home/dan/sqlite/%'
  63 */
  64 #include "sqliteInt.h"
  65 #if defined(INCLUDE_SQLITE_TCL_H)
  66 #  include "sqlite_tcl.h"
  67 #else
  68 #  include "tcl.h"
  69 #endif
  70
  71 #include <stdlib.h>
  72 #include <string.h>
  73 #include <sys/types.h>
  74 #include <sys/stat.h>
  75 #include <fcntl.h>
  76
  77 #if SQLITE_OS_UNIX || defined(__MINGW_H)
  78 # include <unistd.h>
  79 # include <dirent.h>
  80 # ifndef DIRENT
  81 #  define DIRENT dirent
  82 # endif
  83 #endif
  84 #if SQLITE_OS_WIN
  85 # include <io.h>
  86 # if !defined(__MINGW_H)
  87 #  include "test_windirent.h"
  88 # endif
  89 # ifndef S_ISREG
  90 #  define S_ISREG(mode) (((mode) & S_IFMT) == S_IFREG)
  91 # endif
  92 #endif
  93
  94 #ifndef SQLITE_OMIT_VIRTUALTABLE
  95
  96 typedef struct fs_vtab fs_vtab;
  97 typedef struct fs_cursor fs_cursor;
  98
  99 /*
 100 ** A fs virtual-table object
 101 */
 102 struct fs_vtab {
 103   sqlite3_vtab base;
 104   sqlite3 *db;
 105   char *zDb;                      /* Name of db containing zTbl */
 106   char *zTbl;                     /* Name of docid->file map table */
 107 };
 108
 109 /* A fs cursor object */
 110 struct fs_cursor {
 111   sqlite3_vtab_cursor base;
 112   sqlite3_stmt *pStmt;
 113   char *zBuf;
 114   int nBuf;
 115   int nAlloc;
 116 };
 117
 118 /*************************************************************************
 119 ** Start of fsdir implementation.
 120 */
 121 typedef struct FsdirVtab FsdirVtab;
 122 typedef struct FsdirCsr FsdirCsr;
 123 struct FsdirVtab {
 124   sqlite3_vtab base;
 125 };
 126
 127 struct FsdirCsr {
 128   sqlite3_vtab_cursor base;
 129   char *zDir;                     /* Buffer containing directory scanned */
 130   DIR *pDir;                      /* Open directory */
 131   sqlite3_int64 iRowid;
 132   struct DIRENT entry;            /* Current entry */
 133 };
 134
 135 /*
 136 ** This function is the implementation of both the xConnect and xCreate
 137 ** methods of the fsdir virtual table.
 138 **
 139 ** The argv[] array contains the following:
 140 **
 141 **   argv[0]   -> module name  ("fs")
 142 **   argv[1]   -> database name
 143 **   argv[2]   -> table name
 144 **   argv[...] -> other module argument fields.
 145 */
 146 static int fsdirConnect(
 147   sqlite3 *db,
 148   void *pAux,
 149   int argc, const char *const*argv,
 150   sqlite3_vtab **ppVtab,
 151   char **pzErr
 152 ){
 153   FsdirVtab *pTab;
 154
 155   if( argc!=3 ){
 156     *pzErr = sqlite3_mprintf("wrong number of arguments");
 157     return SQLITE_ERROR;
 158   }
 159
 160   pTab = (FsdirVtab *)sqlite3_malloc(sizeof(FsdirVtab));
 161   if( !pTab ) return SQLITE_NOMEM;
 162   memset(pTab, 0, sizeof(FsdirVtab));
 163
 164   *ppVtab = &pTab->base;
 165   sqlite3_declare_vtab(db, "CREATE TABLE xyz(dir, name);");
 166
 167   return SQLITE_OK;
 168 }
 169
 170 /*
 171 ** xDestroy/xDisconnect implementation.
 172 */
 173 static int fsdirDisconnect(sqlite3_vtab *pVtab){
 174   sqlite3_free(pVtab);
 175   return SQLITE_OK;
 176 }
 177
 178 /*
 179 ** xBestIndex implementation. The only constraint supported is:
 180 **
 181 **   (dir = ?)
 182 */
 183 static int fsdirBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
 184   int ii;
 185
 186   pIdxInfo->estimatedCost = 1000000000.0;
 187
 188   for(ii=0; ii<pIdxInfo->nConstraint; ii++){
 189     struct sqlite3_index_constraint const *p = &pIdxInfo->aConstraint[ii];
 190     if( p->iColumn==0 && p->usable && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
 191       struct sqlite3_index_constraint_usage *pUsage;
 192       pUsage = &pIdxInfo->aConstraintUsage[ii];
 193       pUsage->omit = 1;
 194       pUsage->argvIndex = 1;
 195       pIdxInfo->idxNum = 1;
 196       pIdxInfo->estimatedCost = 1.0;
 197       break;
 198     }
 199   }
 200
 201   return SQLITE_OK;
 202 }
 203
 204 /*
 205 ** xOpen implementation.
 206 **
 207 ** Open a new fsdir cursor.
 208 */
 209 static int fsdirOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 210   FsdirCsr *pCur;
 211   /* Allocate an extra 256 bytes because it is undefined how big dirent.d_name
 212   ** is and we need enough space.  Linux provides plenty already, but
 213   ** Solaris only provides one byte. */
 214   pCur = (FsdirCsr*)sqlite3_malloc(sizeof(FsdirCsr)+256);
 215   if( pCur==0 ) return SQLITE_NOMEM;
 216   memset(pCur, 0, sizeof(FsdirCsr));
 217   *ppCursor = &pCur->base;
 218   return SQLITE_OK;
 219 }
 220
 221 /*
 222 ** Close a fsdir cursor.
 223 */
 224 static int fsdirClose(sqlite3_vtab_cursor *cur){
 225   FsdirCsr *pCur = (FsdirCsr*)cur;
 226   if( pCur->pDir ) closedir(pCur->pDir);
 227   sqlite3_free(pCur->zDir);
 228   sqlite3_free(pCur);
 229   return SQLITE_OK;
 230 }
 231
 232 /*
 233 ** Skip the cursor to the next entry.
 234 */
 235 static int fsdirNext(sqlite3_vtab_cursor *cur){
 236   FsdirCsr *pCsr = (FsdirCsr*)cur;
 237
 238   if( pCsr->pDir ){
 239     struct DIRENT *pRes = 0;
 240 #if defined(__MINGW_H)
 241     pRes = readdir(pCsr->pDir);
 242     if( pRes!=0 ){
 243       memcpy(&pCsr->entry, pRes, sizeof(struct DIRENT));
 244     }
 245 #else
 246     readdir_r(pCsr->pDir, &pCsr->entry, &pRes);
 247 #endif
 248     if( pRes==0 ){
 249       closedir(pCsr->pDir);
 250       pCsr->pDir = 0;
 251     }
 252     pCsr->iRowid++;
 253   }
 254
 255   return SQLITE_OK;
 256 }
 257
 258 /*
 259 ** xFilter method implementation.
 260 */
 261 static int fsdirFilter(
 262   sqlite3_vtab_cursor *pVtabCursor,
 263   int idxNum, const char *idxStr,
 264   int argc, sqlite3_value **argv
 265 ){
 266   FsdirCsr *pCsr = (FsdirCsr*)pVtabCursor;
 267   const char *zDir;
 268   int nDir;
 269
 270
 271   if( idxNum!=1 || argc!=1 ){
 272     return SQLITE_ERROR;
 273   }
 274
 275   pCsr->iRowid = 0;
 276   sqlite3_free(pCsr->zDir);
 277   if( pCsr->pDir ){
 278     closedir(pCsr->pDir);
 279     pCsr->pDir = 0;
 280   }
 281
 282   zDir = (const char*)sqlite3_value_text(argv[0]);
 283   nDir = sqlite3_value_bytes(argv[0]);
 284   pCsr->zDir = sqlite3_malloc(nDir+1);
 285   if( pCsr->zDir==0 ) return SQLITE_NOMEM;
 286   memcpy(pCsr->zDir, zDir, nDir+1);
 287
 288   pCsr->pDir = opendir(pCsr->zDir);
 289   return fsdirNext(pVtabCursor);
 290 }
 291
 292 /*
 293 ** xEof method implementation.
 294 */
 295 static int fsdirEof(sqlite3_vtab_cursor *cur){
 296   FsdirCsr *pCsr = (FsdirCsr*)cur;
 297   return pCsr->pDir==0;
 298 }
 299
 300 /*
 301 ** xColumn method implementation.
 302 */
 303 static int fsdirColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
 304   FsdirCsr *pCsr = (FsdirCsr*)cur;
 305   switch( i ){
 306     case 0: /* dir */
 307       sqlite3_result_text(ctx, pCsr->zDir, -1, SQLITE_STATIC);
 308       break;
 309
 310     case 1: /* name */
 311       sqlite3_result_text(ctx, pCsr->entry.d_name, -1, SQLITE_TRANSIENT);
 312       break;
 313
 314     default:
 315       assert( 0 );
 316   }
 317
 318   return SQLITE_OK;
 319 }
 320
 321 /*
 322 ** xRowid method implementation.
 323 */
 324 static int fsdirRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
 325   FsdirCsr *pCsr = (FsdirCsr*)cur;
 326   *pRowid = pCsr->iRowid;
 327   return SQLITE_OK;
 328 }
 329 /*
 330 ** End of fsdir implementation.
 331 *************************************************************************/
 332
 333 /*************************************************************************
 334 ** Start of fstree implementation.
 335 */
 336 typedef struct FstreeVtab FstreeVtab;
 337 typedef struct FstreeCsr FstreeCsr;
 338 struct FstreeVtab {
 339   sqlite3_vtab base;
 340   sqlite3 *db;
 341 };
 342
 343 struct FstreeCsr {
 344   sqlite3_vtab_cursor base;
 345   sqlite3_stmt *pStmt;            /* Statement to list paths */
 346   int fd;                         /* File descriptor open on current path */
 347 };
 348
 349 /*
 350 ** This function is the implementation of both the xConnect and xCreate
 351 ** methods of the fstree virtual table.
 352 **
 353 ** The argv[] array contains the following:
 354 **
 355 **   argv[0]   -> module name  ("fs")
 356 **   argv[1]   -> database name
 357 **   argv[2]   -> table name
 358 **   argv[...] -> other module argument fields.
 359 */
 360 static int fstreeConnect(
 361   sqlite3 *db,
 362   void *pAux,
 363   int argc, const char *const*argv,
 364   sqlite3_vtab **ppVtab,
 365   char **pzErr
 366 ){
 367   FstreeVtab *pTab;
 368
 369   if( argc!=3 ){
 370     *pzErr = sqlite3_mprintf("wrong number of arguments");
 371     return SQLITE_ERROR;
 372   }
 373
 374   pTab = (FstreeVtab *)sqlite3_malloc(sizeof(FstreeVtab));
 375   if( !pTab ) return SQLITE_NOMEM;
 376   memset(pTab, 0, sizeof(FstreeVtab));
 377   pTab->db = db;
 378
 379   *ppVtab = &pTab->base;
 380   sqlite3_declare_vtab(db, "CREATE TABLE xyz(path, size, data);");
 381
 382   return SQLITE_OK;
 383 }
 384
 385 /*
 386 ** xDestroy/xDisconnect implementation.
 387 */
 388 static int fstreeDisconnect(sqlite3_vtab *pVtab){
 389   sqlite3_free(pVtab);
 390   return SQLITE_OK;
 391 }
 392
 393 /*
 394 ** xBestIndex implementation. The only constraint supported is:
 395 **
 396 **   (dir = ?)
 397 */
 398 static int fstreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
 399   int ii;
 400
 401   for(ii=0; ii<pIdxInfo->nConstraint; ii++){
 402     struct sqlite3_index_constraint const *p = &pIdxInfo->aConstraint[ii];
 403     if( p->iColumn==0 && p->usable && (
 404           p->op==SQLITE_INDEX_CONSTRAINT_GLOB
 405        || p->op==SQLITE_INDEX_CONSTRAINT_LIKE
 406        || p->op==SQLITE_INDEX_CONSTRAINT_EQ
 407     )){
 408       struct sqlite3_index_constraint_usage *pUsage;
 409       pUsage = &pIdxInfo->aConstraintUsage[ii];
 410       pIdxInfo->idxNum = p->op;
 411       pUsage->argvIndex = 1;
 412       pIdxInfo->estimatedCost = 100000.0;
 413       return SQLITE_OK;
 414     }
 415   }
 416
 417   pIdxInfo->estimatedCost = 1000000000.0;
 418   return SQLITE_OK;
 419 }
 420
 421 /*
 422 ** xOpen implementation.
 423 **
 424 ** Open a new fstree cursor.
 425 */
 426 static int fstreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 427   FstreeCsr *pCur;
 428   pCur = (FstreeCsr*)sqlite3_malloc(sizeof(FstreeCsr));
 429   if( pCur==0 ) return SQLITE_NOMEM;
 430   memset(pCur, 0, sizeof(FstreeCsr));
 431   pCur->fd = -1;
 432   *ppCursor = &pCur->base;
 433   return SQLITE_OK;
 434 }
 435
 436 static void fstreeCloseFd(FstreeCsr *pCsr){
 437   if( pCsr->fd>=0 ){
 438     close(pCsr->fd);
 439     pCsr->fd = -1;
 440   }
 441 }
 442
 443 /*
 444 ** Close a fstree cursor.
 445 */
 446 static int fstreeClose(sqlite3_vtab_cursor *cur){
 447   FstreeCsr *pCsr = (FstreeCsr*)cur;
 448   sqlite3_finalize(pCsr->pStmt);
 449   fstreeCloseFd(pCsr);
 450   sqlite3_free(pCsr);
 451   return SQLITE_OK;
 452 }
 453
 454 /*
 455 ** Skip the cursor to the next entry.
 456 */
 457 static int fstreeNext(sqlite3_vtab_cursor *cur){
 458   FstreeCsr *pCsr = (FstreeCsr*)cur;
 459   int rc;
 460
 461   fstreeCloseFd(pCsr);
 462   rc = sqlite3_step(pCsr->pStmt);
 463   if( rc!=SQLITE_ROW ){
 464     rc = sqlite3_finalize(pCsr->pStmt);
 465     pCsr->pStmt = 0;
 466   }else{
 467     rc = SQLITE_OK;
 468     pCsr->fd = open((const char*)sqlite3_column_text(pCsr->pStmt, 0), O_RDONLY);
 469   }
 470
 471   return rc;
 472 }
 473
 474 /*
 475 ** xFilter method implementation.
 476 */
 477 static int fstreeFilter(
 478   sqlite3_vtab_cursor *pVtabCursor,
 479   int idxNum, const char *idxStr,
 480   int argc, sqlite3_value **argv
 481 ){
 482   FstreeCsr *pCsr = (FstreeCsr*)pVtabCursor;
 483   FstreeVtab *pTab = (FstreeVtab*)(pCsr->base.pVtab);
 484   int rc;
 485   const char *zSql =
 486 "WITH r(d) AS ("
 487 "  SELECT CASE WHEN dir=?2 THEN ?3 ELSE dir END || '/' || name "
 488 "    FROM fsdir WHERE dir=?1 AND name NOT LIKE '.%'"
 489 "  UNION ALL"
 490 "  SELECT dir || '/' || name FROM r, fsdir WHERE dir=d AND name NOT LIKE '.%'"
 491 ") SELECT d FROM r;";
 492
 493   char *zRoot;
 494   int nRoot;
 495   char *zPrefix;
 496   int nPrefix;
 497   const char *zDir;
 498   int nDir;
 499   char aWild[2] = { '\0', '\0' };
 500
 501 #if SQLITE_OS_WIN
 502   const char *zDrive = windirent_getenv("fstreeDrive");
 503   if( zDrive==0 ){
 504     zDrive = windirent_getenv("SystemDrive");
 505   }
 506   zRoot = sqlite3_mprintf("%s%c", zDrive, '/');
 507   nRoot = sqlite3Strlen30(zRoot);
 508   zPrefix = sqlite3_mprintf("%s", zDrive);
 509   nPrefix = sqlite3Strlen30(zPrefix);
 510 #else
 511   zRoot = "/";
 512   nRoot = 1;
 513   zPrefix = "";
 514   nPrefix = 0;
 515 #endif
 516
 517   zDir = zRoot;
 518   nDir = nRoot;
 519
 520   fstreeCloseFd(pCsr);
 521   sqlite3_finalize(pCsr->pStmt);
 522   pCsr->pStmt = 0;
 523   rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0);
 524   if( rc!=SQLITE_OK ) return rc;
 525
 526   if( idxNum ){
 527     const char *zQuery = (const char*)sqlite3_value_text(argv[0]);
 528     switch( idxNum ){
 529       case SQLITE_INDEX_CONSTRAINT_GLOB:
 530         aWild[0] = '*';
 531         aWild[1] = '?';
 532         break;
 533       case SQLITE_INDEX_CONSTRAINT_LIKE:
 534         aWild[0] = '_';
 535         aWild[1] = '%';
 536         break;
 537     }
 538
 539     if( sqlite3_strnicmp(zQuery, zPrefix, nPrefix)==0 ){
 540       int i;
 541       for(i=nPrefix; zQuery[i]; i++){
 542         if( zQuery[i]==aWild[0] || zQuery[i]==aWild[1] ) break;
 543         if( zQuery[i]=='/' ) nDir = i;
 544       }
 545       zDir = zQuery;
 546     }
 547   }
 548   if( nDir==0 ) nDir = 1;
 549
 550   sqlite3_bind_text(pCsr->pStmt, 1, zDir, nDir, SQLITE_TRANSIENT);
 551   sqlite3_bind_text(pCsr->pStmt, 2, zRoot, nRoot, SQLITE_TRANSIENT);
 552   sqlite3_bind_text(pCsr->pStmt, 3, zPrefix, nPrefix, SQLITE_TRANSIENT);
 553
 554 #if SQLITE_OS_WIN
 555   sqlite3_free(zPrefix);
 556   sqlite3_free(zRoot);
 557 #endif
 558
 559   return fstreeNext(pVtabCursor);
 560 }
 561
 562 /*
 563 ** xEof method implementation.
 564 */
 565 static int fstreeEof(sqlite3_vtab_cursor *cur){
 566   FstreeCsr *pCsr = (FstreeCsr*)cur;
 567   return pCsr->pStmt==0;
 568 }
 569
 570 /*
 571 ** xColumn method implementation.
 572 */
 573 static int fstreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
 574   FstreeCsr *pCsr = (FstreeCsr*)cur;
 575   if( i==0 ){      /* path */
 576     sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pStmt, 0));
 577   }else{
 578     struct stat sBuf;
 579     fstat(pCsr->fd, &sBuf);
 580
 581     if( S_ISREG(sBuf.st_mode) ){
 582       if( i==1 ){
 583         sqlite3_result_int64(ctx, sBuf.st_size);
 584       }else{
 585         int nRead;
 586         char *aBuf = sqlite3_malloc(sBuf.st_mode+1);
 587         if( !aBuf ) return SQLITE_NOMEM;
 588         nRead = read(pCsr->fd, aBuf, sBuf.st_mode);
 589         if( nRead!=sBuf.st_mode ){
 590           return SQLITE_IOERR;
 591         }
 592         sqlite3_result_blob(ctx, aBuf, nRead, SQLITE_TRANSIENT);
 593         sqlite3_free(aBuf);
 594       }
 595     }
 596   }
 597
 598   return SQLITE_OK;
 599 }
 600
 601 /*
 602 ** xRowid method implementation.
 603 */
 604 static int fstreeRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
 605   *pRowid = 0;
 606   return SQLITE_OK;
 607 }
 608 /*
 609 ** End of fstree implementation.
 610 *************************************************************************/
 611
 612
 613
 614
 615 /*
 616 ** This function is the implementation of both the xConnect and xCreate
 617 ** methods of the fs virtual table.
 618 **
 619 ** The argv[] array contains the following:
 620 **
 621 **   argv[0]   -> module name  ("fs")
 622 **   argv[1]   -> database name
 623 **   argv[2]   -> table name
 624 **   argv[...] -> other module argument fields.
 625 */
 626 static int fsConnect(
 627   sqlite3 *db,
 628   void *pAux,
 629   int argc, const char *const*argv,
 630   sqlite3_vtab **ppVtab,
 631   char **pzErr
 632 ){
 633   fs_vtab *pVtab;
 634   int nByte;
 635   const char *zTbl;
 636   const char *zDb = argv[1];
 637
 638   if( argc!=4 ){
 639     *pzErr = sqlite3_mprintf("wrong number of arguments");
 640     return SQLITE_ERROR;
 641   }
 642   zTbl = argv[3];
 643
 644   nByte = sizeof(fs_vtab) + (int)strlen(zTbl) + 1 + (int)strlen(zDb) + 1;
 645   pVtab = (fs_vtab *)sqlite3MallocZero( nByte );
 646   if( !pVtab ) return SQLITE_NOMEM;
 647
 648   pVtab->zTbl = (char *)&pVtab[1];
 649   pVtab->zDb = &pVtab->zTbl[strlen(zTbl)+1];
 650   pVtab->db = db;
 651   memcpy(pVtab->zTbl, zTbl, strlen(zTbl));
 652   memcpy(pVtab->zDb, zDb, strlen(zDb));
 653   *ppVtab = &pVtab->base;
 654   sqlite3_declare_vtab(db, "CREATE TABLE x(path TEXT, data TEXT)");
 655
 656   return SQLITE_OK;
 657 }
 658 /* Note that for this virtual table, the xCreate and xConnect
 659 ** methods are identical. */
 660
 661 static int fsDisconnect(sqlite3_vtab *pVtab){
 662   sqlite3_free(pVtab);
 663   return SQLITE_OK;
 664 }
 665 /* The xDisconnect and xDestroy methods are also the same */
 666
 667 /*
 668 ** Open a new fs cursor.
 669 */
 670 static int fsOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 671   fs_cursor *pCur;
 672   pCur = sqlite3MallocZero(sizeof(fs_cursor));
 673   *ppCursor = &pCur->base;
 674   return SQLITE_OK;
 675 }
 676
 677 /*
 678 ** Close a fs cursor.
 679 */
 680 static int fsClose(sqlite3_vtab_cursor *cur){
 681   fs_cursor *pCur = (fs_cursor *)cur;
 682   sqlite3_finalize(pCur->pStmt);
 683   sqlite3_free(pCur->zBuf);
 684   sqlite3_free(pCur);
 685   return SQLITE_OK;
 686 }
 687
 688 static int fsNext(sqlite3_vtab_cursor *cur){
 689   fs_cursor *pCur = (fs_cursor *)cur;
 690   int rc;
 691
 692   rc = sqlite3_step(pCur->pStmt);
 693   if( rc==SQLITE_ROW || rc==SQLITE_DONE ) rc = SQLITE_OK;
 694
 695   return rc;
 696 }
 697
 698 static int fsFilter(
 699   sqlite3_vtab_cursor *pVtabCursor,
 700   int idxNum, const char *idxStr,
 701   int argc, sqlite3_value **argv
 702 ){
 703   int rc;
 704   fs_cursor *pCur = (fs_cursor *)pVtabCursor;
 705   fs_vtab *p = (fs_vtab *)(pVtabCursor->pVtab);
 706
 707   assert( (idxNum==0 && argc==0) || (idxNum==1 && argc==1) );
 708   if( idxNum==1 ){
 709     char *zStmt = sqlite3_mprintf(
 710         "SELECT * FROM %Q.%Q WHERE rowid=?", p->zDb, p->zTbl);
 711     if( !zStmt ) return SQLITE_NOMEM;
 712     rc = sqlite3_prepare_v2(p->db, zStmt, -1, &pCur->pStmt, 0);
 713     sqlite3_free(zStmt);
 714     if( rc==SQLITE_OK ){
 715       sqlite3_bind_value(pCur->pStmt, 1, argv[0]);
 716     }
 717   }else{
 718     char *zStmt = sqlite3_mprintf("SELECT * FROM %Q.%Q", p->zDb, p->zTbl);
 719     if( !zStmt ) return SQLITE_NOMEM;
 720     rc = sqlite3_prepare_v2(p->db, zStmt, -1, &pCur->pStmt, 0);
 721     sqlite3_free(zStmt);
 722   }
 723
 724   if( rc==SQLITE_OK ){
 725     rc = fsNext(pVtabCursor);
 726   }
 727   return rc;
 728 }
 729
 730 static int fsColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
 731   fs_cursor *pCur = (fs_cursor*)cur;
 732
 733   assert( i==0 || i==1 || i==2 );
 734   if( i==0 ){
 735     sqlite3_result_value(ctx, sqlite3_column_value(pCur->pStmt, 0));
 736   }else{
 737     const char *zFile = (const char *)sqlite3_column_text(pCur->pStmt, 1);
 738     struct stat sbuf;
 739     int fd;
 740
 741     int n;
 742     fd = open(zFile, O_RDONLY);
 743     if( fd<0 ) return SQLITE_IOERR;
 744     fstat(fd, &sbuf);
 745
 746     if( sbuf.st_size>=pCur->nAlloc ){
 747       int nNew = sbuf.st_size*2;
 748       char *zNew;
 749       if( nNew<1024 ) nNew = 1024;
 750
 751       zNew = sqlite3Realloc(pCur->zBuf, nNew);
 752       if( zNew==0 ){
 753         close(fd);
 754         return SQLITE_NOMEM;
 755       }
 756       pCur->zBuf = zNew;
 757       pCur->nAlloc = nNew;
 758     }
 759
 760     n = (int)read(fd, pCur->zBuf, sbuf.st_size);
 761     close(fd);
 762     if( n!=sbuf.st_size ) return SQLITE_ERROR;
 763     pCur->nBuf = sbuf.st_size;
 764     pCur->zBuf[pCur->nBuf] = '\0';
 765
 766     sqlite3_result_text(ctx, pCur->zBuf, -1, SQLITE_TRANSIENT);
 767   }
 768   return SQLITE_OK;
 769 }
 770
 771 static int fsRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
 772   fs_cursor *pCur = (fs_cursor*)cur;
 773   *pRowid = sqlite3_column_int64(pCur->pStmt, 0);
 774   return SQLITE_OK;
 775 }
 776
 777 static int fsEof(sqlite3_vtab_cursor *cur){
 778   fs_cursor *pCur = (fs_cursor*)cur;
 779   return (sqlite3_data_count(pCur->pStmt)==0);
 780 }
 781
 782 static int fsBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
 783   int ii;
 784
 785   for(ii=0; ii<pIdxInfo->nConstraint; ii++){
 786     struct sqlite3_index_constraint const *pCons = &pIdxInfo->aConstraint[ii];
 787     if( pCons->iColumn<0 && pCons->usable
 788            && pCons->op==SQLITE_INDEX_CONSTRAINT_EQ ){
 789       struct sqlite3_index_constraint_usage *pUsage;
 790       pUsage = &pIdxInfo->aConstraintUsage[ii];
 791       pUsage->omit = 0;
 792       pUsage->argvIndex = 1;
 793       pIdxInfo->idxNum = 1;
 794       pIdxInfo->estimatedCost = 1.0;
 795       break;
 796     }
 797   }
 798
 799   return SQLITE_OK;
 800 }
 801
 802 /*
 803 ** A virtual table module that provides read-only access to a
 804 ** Tcl global variable namespace.
 805 */
 806 static sqlite3_module fsModule = {
 807   0,                         /* iVersion */
 808   fsConnect,
 809   fsConnect,
 810   fsBestIndex,
 811   fsDisconnect,
 812   fsDisconnect,
 813   fsOpen,                      /* xOpen - open a cursor */
 814   fsClose,                     /* xClose - close a cursor */
 815   fsFilter,                    /* xFilter - configure scan constraints */
 816   fsNext,                      /* xNext - advance a cursor */
 817   fsEof,                       /* xEof - check for end of scan */
 818   fsColumn,                    /* xColumn - read data */
 819   fsRowid,                     /* xRowid - read data */
 820   0,                           /* xUpdate */
 821   0,                           /* xBegin */
 822   0,                           /* xSync */
 823   0,                           /* xCommit */
 824   0,                           /* xRollback */
 825   0,                           /* xFindMethod */
 826   0,                           /* xRename */
 827 };
 828
 829 static sqlite3_module fsdirModule = {
 830   0,                              /* iVersion */
 831   fsdirConnect,                   /* xCreate */
 832   fsdirConnect,                   /* xConnect */
 833   fsdirBestIndex,                 /* xBestIndex */
 834   fsdirDisconnect,                /* xDisconnect */
 835   fsdirDisconnect,                /* xDestroy */
 836   fsdirOpen,                      /* xOpen - open a cursor */
 837   fsdirClose,                     /* xClose - close a cursor */
 838   fsdirFilter,                    /* xFilter - configure scan constraints */
 839   fsdirNext,                      /* xNext - advance a cursor */
 840   fsdirEof,                       /* xEof - check for end of scan */
 841   fsdirColumn,                    /* xColumn - read data */
 842   fsdirRowid,                     /* xRowid - read data */
 843   0,                              /* xUpdate */
 844   0,                              /* xBegin */
 845   0,                              /* xSync */
 846   0,                              /* xCommit */
 847   0,                              /* xRollback */
 848   0,                              /* xFindMethod */
 849   0,                              /* xRename */
 850 };
 851
 852 static sqlite3_module fstreeModule = {
 853   0,                              /* iVersion */
 854   fstreeConnect,                  /* xCreate */
 855   fstreeConnect,                  /* xConnect */
 856   fstreeBestIndex,                /* xBestIndex */
 857   fstreeDisconnect,               /* xDisconnect */
 858   fstreeDisconnect,               /* xDestroy */
 859   fstreeOpen,                     /* xOpen - open a cursor */
 860   fstreeClose,                    /* xClose - close a cursor */
 861   fstreeFilter,                   /* xFilter - configure scan constraints */
 862   fstreeNext,                     /* xNext - advance a cursor */
 863   fstreeEof,                      /* xEof - check for end of scan */
 864   fstreeColumn,                   /* xColumn - read data */
 865   fstreeRowid,                    /* xRowid - read data */
 866   0,                              /* xUpdate */
 867   0,                              /* xBegin */
 868   0,                              /* xSync */
 869   0,                              /* xCommit */
 870   0,                              /* xRollback */
 871   0,                              /* xFindMethod */
 872   0,                              /* xRename */
 873 };
 874
 875 /*
 876 ** Decode a pointer to an sqlite3 object.
 877 */
 878 extern int getDbPointer(Tcl_Interp *interp, const char *zA, sqlite3 **ppDb);
 879
 880 /*
 881 ** Register the echo virtual table module.
 882 */
 883 static int SQLITE_TCLAPI register_fs_module(
 884   ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
 885   Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
 886   int objc,              /* Number of arguments */
 887   Tcl_Obj *CONST objv[]  /* Command arguments */
 888 ){
 889   sqlite3 *db;
 890   if( objc!=2 ){
 891     Tcl_WrongNumArgs(interp, 1, objv, "DB");
 892     return TCL_ERROR;
 893   }
 894   if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
 895 #ifndef SQLITE_OMIT_VIRTUALTABLE
 896   sqlite3_create_module(db, "fs", &fsModule, (void *)interp);
 897   sqlite3_create_module(db, "fsdir", &fsdirModule, 0);
 898   sqlite3_create_module(db, "fstree", &fstreeModule, 0);
 899 #endif
 900   return TCL_OK;
 901 }
 902
 903 #endif
 904
 905
 906 /*
 907 ** Register commands with the TCL interpreter.
 908 */
 909 int Sqlitetestfs_Init(Tcl_Interp *interp){
 910 #ifndef SQLITE_OMIT_VIRTUALTABLE
 911   static struct {
 912      char *zName;
 913      Tcl_ObjCmdProc *xProc;
 914      void *clientData;
 915   } aObjCmd[] = {
 916      { "register_fs_module",   register_fs_module, 0 },
 917   };
 918   int i;
 919   for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
 920     Tcl_CreateObjCommand(interp, aObjCmd[i].zName,
 921         aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
 922   }
 923 #endif
 924   return TCL_OK;
 925 }