Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
Comment: | Fix for ticket #9: Add the ability to read little-endian database files from a big-endian machine and vice versa. (CVS 704) |
---|---|
Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
ce4b943bf68c160445a58ffccfbabbbd |
User & Date: | drh 2002-08-11 20:10:47.000 |
Context
2002-08-12
| ||
12:29 | Fix for ticket #9 (again). The rollback journal files should now also be byte-order independent. (CVS 705) (check-in: 2fb3fdcdf0 user: drh tags: trunk) | |
2002-08-11
| ||
20:10 | Fix for ticket #9: Add the ability to read little-endian database files from a big-endian machine and vice versa. (CVS 704) (check-in: ce4b943bf6 user: drh tags: trunk) | |
2002-08-06
| ||
12:05 | Fix typos the source to webpages html files. (CVS 703) (check-in: 61bb3af740 user: drh tags: trunk) | |
Changes
Changes to src/btree.c.
1 2 3 4 5 6 7 8 9 10 11 | /* ** 2001 September 15 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* | | | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | /* ** 2001 September 15 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** $Id: btree.c,v 1.69 2002/08/11 20:10:47 drh Exp $ ** ** This file implements a external (disk-based) database using BTrees. ** For a detailed discussion of BTrees, refer to ** ** Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3: ** "Sorting And Searching", pages 473-480. Addison-Wesley ** Publishing Company, Reading, Massachusetts. |
︙ | ︙ | |||
50 51 52 53 54 55 56 57 58 59 60 61 62 63 | ** 1, not 0.) Thus a minimum database contains 2 pages. */ #include "sqliteInt.h" #include "pager.h" #include "btree.h" #include <assert.h> /* ** Forward declarations of structures used only in this file. */ typedef struct PageOne PageOne; typedef struct MemPage MemPage; typedef struct PageHdr PageHdr; typedef struct Cell Cell; | > > > > > > > > > > > > > > > > > > > > > > > > | 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 | ** 1, not 0.) Thus a minimum database contains 2 pages. */ #include "sqliteInt.h" #include "pager.h" #include "btree.h" #include <assert.h> /* ** Macros used for byteswapping. B is a pointer to the Btree ** structure. This is needed to access the Btree.needSwab boolean ** in order to tell if byte swapping is needed or not. ** X is an unsigned integer. SWAB16 byte swaps a 16-bit integer. ** SWAB32 byteswaps a 32-bit integer. */ #define SWAB16(B,X) ((B)->needSwab? swab16(X) : (X)) #define SWAB32(B,X) ((B)->needSwab? swab32(X) : (X)) #define SWAB_ADD(B,X,A) \ if((B)->needSwab){ X=swab32(swab32(X)+A); }else{ X += (A); } /* ** The following global variable - available only if SQLITE_TEST is ** defined - is used to determine whether new databases are created in ** native byte order or in non-native byte order. Non-native byte order ** databases are created for testing purposes only. Under normal operation, ** only native byte-order databases should be created, but we should be ** able to read or write existing databases regardless of the byteorder. */ #ifdef SQLITE_TEST int btree_native_byte_order = 1; #endif /* ** Forward declarations of structures used only in this file. */ typedef struct PageOne PageOne; typedef struct MemPage MemPage; typedef struct PageHdr PageHdr; typedef struct Cell Cell; |
︙ | ︙ | |||
163 164 165 166 167 168 169 | /* ** The key and data size are split into a lower 16-bit segment and an ** upper 8-bit segment in order to pack them together into a smaller ** space. The following macros reassembly a key or data size back ** into an integer. */ | | | | 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 | /* ** The key and data size are split into a lower 16-bit segment and an ** upper 8-bit segment in order to pack them together into a smaller ** space. The following macros reassembly a key or data size back ** into an integer. */ #define NKEY(b,h) (SWAB16(b,h.nKey) + h.nKeyHi*65536) #define NDATA(b,h) (SWAB16(b,h.nData) + h.nDataHi*65536) /* ** The minimum size of a complete Cell. The Cell must contain a header ** and at least 4 bytes of payload. */ #define MIN_CELL_SIZE (sizeof(CellHdr)+4) |
︙ | ︙ | |||
314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 | struct Btree { Pager *pPager; /* The page cache */ BtCursor *pCursor; /* A list of all open cursors */ PageOne *page1; /* First page of the database */ u8 inTrans; /* True if a transaction is in progress */ u8 inCkpt; /* True if there is a checkpoint on the transaction */ u8 readOnly; /* True if the underlying file is readonly */ Hash locks; /* Key: root page number. Data: lock count */ }; typedef Btree Bt; /* ** A cursor is a pointer to a particular entry in the BTree. ** The entry is identified by its MemPage and the index in ** MemPage.apCell[] of the entry. */ struct BtCursor { Btree *pBt; /* The Btree to which this cursor belongs */ BtCursor *pNext, *pPrev; /* Forms a linked list of all cursors */ Pgno pgnoRoot; /* The root page of this tree */ MemPage *pPage; /* Page that contains the entry */ int idx; /* Index of the entry in pPage->apCell[] */ u8 wrFlag; /* True if writable */ u8 bSkipNext; /* sqliteBtreeNext() is no-op if true */ u8 iMatch; /* compare result from last sqliteBtreeMoveto() */ }; /* ** Compute the total number of bytes that a Cell needs on the main ** database page. The number returned includes the Cell header, ** local payload storage, and the pointer to overflow pages (if ** applicable). Additional space allocated on overflow pages ** is NOT included in the value returned from this routine. */ | > > > > > > > > > > > > | | | | | | | | | > | | | | | | | | | | > | > | | | | > > > | > | | | | | | | | | | > | > | | | | | | | 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 | struct Btree { Pager *pPager; /* The page cache */ BtCursor *pCursor; /* A list of all open cursors */ PageOne *page1; /* First page of the database */ u8 inTrans; /* True if a transaction is in progress */ u8 inCkpt; /* True if there is a checkpoint on the transaction */ u8 readOnly; /* True if the underlying file is readonly */ u8 needSwab; /* Need to byte-swapping */ Hash locks; /* Key: root page number. Data: lock count */ }; typedef Btree Bt; /* ** A cursor is a pointer to a particular entry in the BTree. ** The entry is identified by its MemPage and the index in ** MemPage.apCell[] of the entry. */ struct BtCursor { Btree *pBt; /* The Btree to which this cursor belongs */ BtCursor *pNext, *pPrev; /* Forms a linked list of all cursors */ Pgno pgnoRoot; /* The root page of this tree */ MemPage *pPage; /* Page that contains the entry */ int idx; /* Index of the entry in pPage->apCell[] */ u8 wrFlag; /* True if writable */ u8 bSkipNext; /* sqliteBtreeNext() is no-op if true */ u8 iMatch; /* compare result from last sqliteBtreeMoveto() */ }; /* ** Routines for byte swapping. */ u16 swab16(u16 x){ return ((x & 0xff)<<8) | ((x>>8)&0xff); } u32 swab32(u32 x){ return ((x & 0xff)<<24) | ((x & 0xff00)<<8) | ((x>>8) & 0xff00) | ((x>>24)&0xff); } /* ** Compute the total number of bytes that a Cell needs on the main ** database page. The number returned includes the Cell header, ** local payload storage, and the pointer to overflow pages (if ** applicable). Additional space allocated on overflow pages ** is NOT included in the value returned from this routine. */ static int cellSize(Btree *pBt, Cell *pCell){ int n = NKEY(pBt, pCell->h) + NDATA(pBt, pCell->h); if( n>MX_LOCAL_PAYLOAD ){ n = MX_LOCAL_PAYLOAD + sizeof(Pgno); }else{ n = ROUNDUP(n); } n += sizeof(CellHdr); return n; } /* ** Defragment the page given. All Cells are moved to the ** beginning of the page and all free space is collected ** into one big FreeBlk at the end of the page. */ static void defragmentPage(Btree *pBt, MemPage *pPage){ int pc, i, n; FreeBlk *pFBlk; char newPage[SQLITE_PAGE_SIZE]; assert( sqlitepager_iswriteable(pPage) ); assert( pPage->isInit ); pc = sizeof(PageHdr); pPage->u.hdr.firstCell = SWAB16(pBt, pc); memcpy(newPage, pPage->u.aDisk, pc); for(i=0; i<pPage->nCell; i++){ Cell *pCell = pPage->apCell[i]; /* This routine should never be called on an overfull page. The ** following asserts verify that constraint. */ assert( Addr(pCell) > Addr(pPage) ); assert( Addr(pCell) < Addr(pPage) + SQLITE_PAGE_SIZE ); n = cellSize(pBt, pCell); pCell->h.iNext = SWAB16(pBt, pc + n); memcpy(&newPage[pc], pCell, n); pPage->apCell[i] = (Cell*)&pPage->u.aDisk[pc]; pc += n; } assert( pPage->nFree==SQLITE_PAGE_SIZE-pc ); memcpy(pPage->u.aDisk, newPage, pc); if( pPage->nCell>0 ){ pPage->apCell[pPage->nCell-1]->h.iNext = 0; } pFBlk = (FreeBlk*)&pPage->u.aDisk[pc]; pFBlk->iSize = SWAB16(pBt, SQLITE_PAGE_SIZE - pc); pFBlk->iNext = 0; pPage->u.hdr.firstFree = SWAB16(pBt, pc); memset(&pFBlk[1], 0, SQLITE_PAGE_SIZE - pc - sizeof(FreeBlk)); } /* ** Allocate nByte bytes of space on a page. nByte must be a ** multiple of 4. ** ** Return the index into pPage->u.aDisk[] of the first byte of ** the new allocation. Or return 0 if there is not enough free ** space on the page to satisfy the allocation request. ** ** If the page contains nBytes of free space but does not contain ** nBytes of contiguous free space, then this routine automatically ** calls defragementPage() to consolidate all free space before ** allocating the new chunk. */ static int allocateSpace(Btree *pBt, MemPage *pPage, int nByte){ FreeBlk *p; u16 *pIdx; int start; int cnt = 0; int iSize; assert( sqlitepager_iswriteable(pPage) ); assert( nByte==ROUNDUP(nByte) ); assert( pPage->isInit ); if( pPage->nFree<nByte || pPage->isOverfull ) return 0; pIdx = &pPage->u.hdr.firstFree; p = (FreeBlk*)&pPage->u.aDisk[SWAB16(pBt, *pIdx)]; while( (iSize = SWAB16(pBt, p->iSize))<nByte ){ assert( cnt++ < SQLITE_PAGE_SIZE/4 ); if( p->iNext==0 ){ defragmentPage(pBt, pPage); pIdx = &pPage->u.hdr.firstFree; }else{ pIdx = &p->iNext; } p = (FreeBlk*)&pPage->u.aDisk[SWAB16(pBt, *pIdx)]; } if( iSize==nByte ){ start = SWAB16(pBt, *pIdx); *pIdx = p->iNext; }else{ FreeBlk *pNew; start = SWAB16(pBt, *pIdx); pNew = (FreeBlk*)&pPage->u.aDisk[start + nByte]; pNew->iNext = p->iNext; pNew->iSize = SWAB16(pBt, iSize - nByte); *pIdx = SWAB16(pBt, start + nByte); } pPage->nFree -= nByte; return start; } /* ** Return a section of the MemPage.u.aDisk[] to the freelist. ** The first byte of the new free block is pPage->u.aDisk[start] ** and the size of the block is "size" bytes. Size must be ** a multiple of 4. ** ** Most of the effort here is involved in coalesing adjacent ** free blocks into a single big free block. */ static void freeSpace(Btree *pBt, MemPage *pPage, int start, int size){ int end = start + size; u16 *pIdx, idx; FreeBlk *pFBlk; FreeBlk *pNew; FreeBlk *pNext; int iSize; assert( sqlitepager_iswriteable(pPage) ); assert( size == ROUNDUP(size) ); assert( start == ROUNDUP(start) ); assert( pPage->isInit ); pIdx = &pPage->u.hdr.firstFree; idx = SWAB16(pBt, *pIdx); while( idx!=0 && idx<start ){ pFBlk = (FreeBlk*)&pPage->u.aDisk[idx]; iSize = SWAB16(pBt, pFBlk->iSize); if( idx + iSize == start ){ pFBlk->iSize = SWAB16(pBt, iSize + size); if( idx + iSize + size == SWAB16(pBt, pFBlk->iNext) ){ pNext = (FreeBlk*)&pPage->u.aDisk[idx + iSize + size]; if( pBt->needSwab ){ pFBlk->iSize = swab16(swab16(pNext->iSize)+iSize+size); }else{ pFBlk->iSize += pNext->iSize; } pFBlk->iNext = pNext->iNext; } pPage->nFree += size; return; } pIdx = &pFBlk->iNext; idx = SWAB16(pBt, *pIdx); } pNew = (FreeBlk*)&pPage->u.aDisk[start]; if( idx != end ){ pNew->iSize = SWAB16(pBt, size); pNew->iNext = SWAB16(pBt, idx); }else{ pNext = (FreeBlk*)&pPage->u.aDisk[idx]; pNew->iSize = SWAB16(pBt, size + SWAB16(pBt, pNext->iSize)); pNew->iNext = pNext->iNext; } *pIdx = SWAB16(pBt, start); pPage->nFree += size; } /* ** Initialize the auxiliary information for a disk block. ** ** The pParent parameter must be a pointer to the MemPage which ** is the parent of the page being initialized. The root of the ** BTree (usually page 2) has no parent and so for that page, ** pParent==NULL. ** ** Return SQLITE_OK on success. If we see that the page does ** not contained a well-formed database page, then return ** SQLITE_CORRUPT. Note that a return of SQLITE_OK does not ** guarantee that the page is well-formed. It only shows that ** we failed to detect any corruption. */ static int initPage(Bt *pBt, MemPage *pPage, Pgno pgnoThis, MemPage *pParent){ int idx; /* An index into pPage->u.aDisk[] */ Cell *pCell; /* A pointer to a Cell in pPage->u.aDisk[] */ FreeBlk *pFBlk; /* A pointer to a free block in pPage->u.aDisk[] */ int sz; /* The size of a Cell in bytes */ int freeSpace; /* Amount of free space on the page */ if( pPage->pParent ){ assert( pPage->pParent==pParent ); return SQLITE_OK; } if( pParent ){ pPage->pParent = pParent; sqlitepager_ref(pParent); } if( pPage->isInit ) return SQLITE_OK; pPage->isInit = 1; pPage->nCell = 0; freeSpace = USABLE_SPACE; idx = SWAB16(pBt, pPage->u.hdr.firstCell); while( idx!=0 ){ if( idx>SQLITE_PAGE_SIZE-MIN_CELL_SIZE ) goto page_format_error; if( idx<sizeof(PageHdr) ) goto page_format_error; if( idx!=ROUNDUP(idx) ) goto page_format_error; pCell = (Cell*)&pPage->u.aDisk[idx]; sz = cellSize(pBt, pCell); if( idx+sz > SQLITE_PAGE_SIZE ) goto page_format_error; freeSpace -= sz; pPage->apCell[pPage->nCell++] = pCell; idx = SWAB16(pBt, pCell->h.iNext); } pPage->nFree = 0; idx = SWAB16(pBt, pPage->u.hdr.firstFree); while( idx!=0 ){ int iNext; if( idx>SQLITE_PAGE_SIZE-sizeof(FreeBlk) ) goto page_format_error; if( idx<sizeof(PageHdr) ) goto page_format_error; pFBlk = (FreeBlk*)&pPage->u.aDisk[idx]; pPage->nFree += SWAB16(pBt, pFBlk->iSize); iNext = SWAB16(pBt, pFBlk->iNext); if( iNext>0 && iNext <= idx ) goto page_format_error; idx = iNext; } if( pPage->nCell==0 && pPage->nFree==0 ){ /* As a special case, an uninitialized root page appears to be ** an empty database */ return SQLITE_OK; } if( pPage->nFree!=freeSpace ) goto page_format_error; return SQLITE_OK; page_format_error: return SQLITE_CORRUPT; } /* ** Set up a raw page so that it looks like a database page holding ** no entries. */ static void zeroPage(Btree *pBt, MemPage *pPage){ PageHdr *pHdr; FreeBlk *pFBlk; assert( sqlitepager_iswriteable(pPage) ); memset(pPage, 0, SQLITE_PAGE_SIZE); pHdr = &pPage->u.hdr; pHdr->firstCell = 0; pHdr->firstFree = SWAB16(pBt, sizeof(*pHdr)); pFBlk = (FreeBlk*)&pHdr[1]; pFBlk->iNext = 0; pPage->nFree = SQLITE_PAGE_SIZE - sizeof(*pHdr); pFBlk->iSize = SWAB16(pBt, pPage->nFree); pPage->nCell = 0; pPage->isOverfull = 0; } /* ** This routine is called when the reference count for a page ** reaches zero. We need to unref the pParent pointer when that |
︙ | ︙ | |||
690 691 692 693 694 695 696 | if( rc!=SQLITE_OK ) return rc; /* Do some checking to help insure the file we opened really is ** a valid database file. */ if( sqlitepager_pagecount(pBt->pPager)>0 ){ PageOne *pP1 = pBt->page1; | | > > | 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 | if( rc!=SQLITE_OK ) return rc; /* Do some checking to help insure the file we opened really is ** a valid database file. */ if( sqlitepager_pagecount(pBt->pPager)>0 ){ PageOne *pP1 = pBt->page1; if( strcmp(pP1->zMagic,zMagicHeader)!=0 || (pP1->iMagic!=MAGIC && swab32(pP1->iMagic)!=MAGIC) ){ rc = SQLITE_CORRUPT; goto page1_init_failed; } pBt->needSwab = pP1->iMagic!=MAGIC; } return rc; page1_init_failed: sqlitepager_unref(pBt->page1); pBt->page1 = 0; return rc; |
︙ | ︙ | |||
742 743 744 745 746 747 748 | if( rc ) return rc; rc = sqlitepager_write(pRoot); if( rc ){ sqlitepager_unref(pRoot); return rc; } strcpy(pP1->zMagic, zMagicHeader); | > > | > > > > > > > > > | | 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 | if( rc ) return rc; rc = sqlitepager_write(pRoot); if( rc ){ sqlitepager_unref(pRoot); return rc; } strcpy(pP1->zMagic, zMagicHeader); #ifdef SQLITE_TEST if( btree_native_byte_order ){ pP1->iMagic = MAGIC; pBt->needSwab = 0; }else{ pP1->iMagic = swab32(MAGIC); pBt->needSwab = 1; } #else pP1->iMagic = MAGIC; pBt->needSwab = 0; #endif zeroPage(pBt, pRoot); sqlitepager_unref(pRoot); return SQLITE_OK; } /* ** Attempt to start a new transaction. ** |
︙ | ︙ | |||
932 933 934 935 936 937 938 | goto create_cursor_exception; } pCur->pgnoRoot = (Pgno)iTable; rc = sqlitepager_get(pBt->pPager, pCur->pgnoRoot, (void**)&pCur->pPage); if( rc!=SQLITE_OK ){ goto create_cursor_exception; } | | | 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 | goto create_cursor_exception; } pCur->pgnoRoot = (Pgno)iTable; rc = sqlitepager_get(pBt->pPager, pCur->pgnoRoot, (void**)&pCur->pPage); if( rc!=SQLITE_OK ){ goto create_cursor_exception; } rc = initPage(pBt, pCur->pPage, pCur->pgnoRoot, 0); if( rc!=SQLITE_OK ){ goto create_cursor_exception; } nLock = (ptr)sqliteHashFind(&pBt->locks, 0, iTable); if( nLock<0 || (nLock>0 && wrFlag) ){ rc = SQLITE_LOCKED; goto create_cursor_exception; |
︙ | ︙ | |||
1031 1032 1033 1034 1035 1036 1037 | MemPage *pPage; pPage = pCur->pPage; if( pPage==0 || pCur->idx >= pPage->nCell ){ *pSize = 0; }else{ pCell = pPage->apCell[pCur->idx]; | | > | | | | 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 | MemPage *pPage; pPage = pCur->pPage; if( pPage==0 || pCur->idx >= pPage->nCell ){ *pSize = 0; }else{ pCell = pPage->apCell[pCur->idx]; *pSize = NKEY(pCur->pBt, pCell->h); } return SQLITE_OK; } /* ** Read payload information from the entry that the pCur cursor is ** pointing to. Begin reading the payload at "offset" and read ** a total of "amt" bytes. Put the result in zBuf. ** ** This routine does not make a distinction between key and data. ** It just reads bytes from the payload area. */ static int getPayload(BtCursor *pCur, int offset, int amt, char *zBuf){ char *aPayload; Pgno nextPage; int rc; Btree *pBt = pCur->pBt; assert( pCur!=0 && pCur->pPage!=0 ); assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell ); aPayload = pCur->pPage->apCell[pCur->idx]->aPayload; if( offset<MX_LOCAL_PAYLOAD ){ int a = amt; if( a+offset>MX_LOCAL_PAYLOAD ){ a = MX_LOCAL_PAYLOAD - offset; } memcpy(zBuf, &aPayload[offset], a); if( a==amt ){ return SQLITE_OK; } offset = 0; zBuf += a; amt -= a; }else{ offset -= MX_LOCAL_PAYLOAD; } if( amt>0 ){ nextPage = SWAB32(pBt, pCur->pPage->apCell[pCur->idx]->ovfl); } while( amt>0 && nextPage ){ OverflowPage *pOvfl; rc = sqlitepager_get(pBt->pPager, nextPage, (void**)&pOvfl); if( rc!=0 ){ return rc; } nextPage = SWAB32(pBt, pOvfl->iNext); if( offset<OVERFLOW_SIZE ){ int a = amt; if( a + offset > OVERFLOW_SIZE ){ a = OVERFLOW_SIZE - offset; } memcpy(zBuf, &pOvfl->aPayload[offset], a); offset = 0; |
︙ | ︙ | |||
1117 1118 1119 1120 1121 1122 1123 | if( amt==0 ) return 0; pPage = pCur->pPage; if( pPage==0 ) return 0; if( pCur->idx >= pPage->nCell ){ return 0; } pCell = pPage->apCell[pCur->idx]; | | | | 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 | if( amt==0 ) return 0; pPage = pCur->pPage; if( pPage==0 ) return 0; if( pCur->idx >= pPage->nCell ){ return 0; } pCell = pPage->apCell[pCur->idx]; if( amt+offset > NKEY(pCur->pBt, pCell->h) ){ amt = NKEY(pCur->pBt, pCell->h) - offset; if( amt<=0 ){ return 0; } } getPayload(pCur, offset, amt, zBuf); return amt; } |
︙ | ︙ | |||
1143 1144 1145 1146 1147 1148 1149 | MemPage *pPage; pPage = pCur->pPage; if( pPage==0 || pCur->idx >= pPage->nCell ){ *pSize = 0; }else{ pCell = pPage->apCell[pCur->idx]; | | > > | | | | 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 | MemPage *pPage; pPage = pCur->pPage; if( pPage==0 || pCur->idx >= pPage->nCell ){ *pSize = 0; }else{ pCell = pPage->apCell[pCur->idx]; *pSize = NDATA(pCur->pBt, pCell->h); } return SQLITE_OK; } /* ** Read part of the data associated with cursor pCur. A maximum ** of "amt" bytes will be transfered into zBuf[]. The transfer ** begins at "offset". The number of bytes actually read is ** returned. The amount returned will be smaller than the ** amount requested if there are not enough bytes in the data ** to satisfy the request. */ int sqliteBtreeData(BtCursor *pCur, int offset, int amt, char *zBuf){ Cell *pCell; MemPage *pPage; int nData; if( amt<0 ) return 0; if( offset<0 ) return 0; if( amt==0 ) return 0; pPage = pCur->pPage; if( pPage==0 || pCur->idx >= pPage->nCell ){ return 0; } pCell = pPage->apCell[pCur->idx]; nData = NDATA(pCur->pBt, pCell->h); if( amt+offset > nData ){ amt = nData - offset; if( amt<=0 ){ return 0; } } getPayload(pCur, offset + NKEY(pCur->pBt, pCell->h), amt, zBuf); return amt; } /* ** Compare an external key against the key on the entry that pCur points to. ** ** The external key is pKey and is nKey bytes long. The last nIgnore bytes |
︙ | ︙ | |||
1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 | int nKey, /* Number of bytes in pKey */ int nIgnore, /* Ignore this many bytes at the end of pCur */ int *pResult /* Write the result here */ ){ Pgno nextPage; int n, c, rc, nLocal; Cell *pCell; const char *zKey = (const char*)pKey; assert( pCur->pPage ); assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell ); pCell = pCur->pPage->apCell[pCur->idx]; | > | | | | | 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 | int nKey, /* Number of bytes in pKey */ int nIgnore, /* Ignore this many bytes at the end of pCur */ int *pResult /* Write the result here */ ){ Pgno nextPage; int n, c, rc, nLocal; Cell *pCell; Btree *pBt = pCur->pBt; const char *zKey = (const char*)pKey; assert( pCur->pPage ); assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell ); pCell = pCur->pPage->apCell[pCur->idx]; nLocal = NKEY(pBt, pCell->h) - nIgnore; if( nLocal<0 ) nLocal = 0; n = nKey<nLocal ? nKey : nLocal; if( n>MX_LOCAL_PAYLOAD ){ n = MX_LOCAL_PAYLOAD; } c = memcmp(pCell->aPayload, zKey, n); if( c!=0 ){ *pResult = c; return SQLITE_OK; } zKey += n; nKey -= n; nLocal -= n; nextPage = SWAB32(pBt, pCell->ovfl); while( nKey>0 && nLocal>0 ){ OverflowPage *pOvfl; if( nextPage==0 ){ return SQLITE_CORRUPT; } rc = sqlitepager_get(pBt->pPager, nextPage, (void**)&pOvfl); if( rc ){ return rc; } nextPage = SWAB32(pBt, pOvfl->iNext); n = nKey<nLocal ? nKey : nLocal; if( n>OVERFLOW_SIZE ){ n = OVERFLOW_SIZE; } c = memcmp(pOvfl->aPayload, zKey, n); sqlitepager_unref(pOvfl); if( c!=0 ){ |
︙ | ︙ | |||
1266 1267 1268 1269 1270 1271 1272 1273 | /* ** Move the cursor down to a new child page. */ static int moveToChild(BtCursor *pCur, int newPgno){ int rc; MemPage *pNewPage; | > | | | 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 | /* ** Move the cursor down to a new child page. */ static int moveToChild(BtCursor *pCur, int newPgno){ int rc; MemPage *pNewPage; Btree *pBt = pCur->pBt; rc = sqlitepager_get(pBt->pPager, newPgno, (void**)&pNewPage); if( rc ) return rc; rc = initPage(pBt, pNewPage, newPgno, pCur->pPage); if( rc ) return rc; sqlitepager_unref(pCur->pPage); pCur->pPage = pNewPage; pCur->idx = 0; return SQLITE_OK; } |
︙ | ︙ | |||
1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 | pParent = pCur->pPage->pParent; if( pParent==0 ) return SQLITE_INTERNAL; oldPgno = sqlitepager_pagenumber(pCur->pPage); sqlitepager_ref(pParent); sqlitepager_unref(pCur->pPage); pCur->pPage = pParent; pCur->idx = pParent->nCell; for(i=0; i<pParent->nCell; i++){ if( pParent->apCell[i]->h.leftChild==oldPgno ){ pCur->idx = i; break; } } return SQLITE_OK; } /* ** Move the cursor to the root page */ static int moveToRoot(BtCursor *pCur){ MemPage *pNew; int rc; | > > | | | | 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 | pParent = pCur->pPage->pParent; if( pParent==0 ) return SQLITE_INTERNAL; oldPgno = sqlitepager_pagenumber(pCur->pPage); sqlitepager_ref(pParent); sqlitepager_unref(pCur->pPage); pCur->pPage = pParent; pCur->idx = pParent->nCell; oldPgno = SWAB32(pCur->pBt, oldPgno); for(i=0; i<pParent->nCell; i++){ if( pParent->apCell[i]->h.leftChild==oldPgno ){ pCur->idx = i; break; } } return SQLITE_OK; } /* ** Move the cursor to the root page */ static int moveToRoot(BtCursor *pCur){ MemPage *pNew; int rc; Btree *pBt = pCur->pBt; rc = sqlitepager_get(pBt->pPager, pCur->pgnoRoot, (void**)&pNew); if( rc ) return rc; rc = initPage(pBt, pNew, pCur->pgnoRoot, 0); if( rc ) return rc; sqlitepager_unref(pCur->pPage); pCur->pPage = pNew; pCur->idx = 0; return SQLITE_OK; } /* ** Move the cursor down to the left-most leaf entry beneath the ** entry to which it is currently pointing. */ static int moveToLeftmost(BtCursor *pCur){ Pgno pgno; int rc; while( (pgno = pCur->pPage->apCell[pCur->idx]->h.leftChild)!=0 ){ rc = moveToChild(pCur, SWAB32(pCur->pBt, pgno)); if( rc ) return rc; } return SQLITE_OK; } /* Move the cursor to the first entry in the table. Return SQLITE_OK ** on success. Set *pRes to 0 if the cursor actually points to something |
︙ | ︙ | |||
1373 1374 1375 1376 1377 1378 1379 | assert( pCur->pPage->isInit ); if( pCur->pPage->nCell==0 ){ *pRes = 1; return SQLITE_OK; } *pRes = 0; while( (pgno = pCur->pPage->u.hdr.rightChild)!=0 ){ | | | 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 | assert( pCur->pPage->isInit ); if( pCur->pPage->nCell==0 ){ *pRes = 1; return SQLITE_OK; } *pRes = 0; while( (pgno = pCur->pPage->u.hdr.rightChild)!=0 ){ rc = moveToChild(pCur, SWAB32(pCur->pBt, pgno)); if( rc ) return rc; } pCur->idx = pCur->pPage->nCell-1; pCur->bSkipNext = 0; return rc; } |
︙ | ︙ | |||
1443 1444 1445 1446 1447 1448 1449 | chldPg = pPage->apCell[lwr]->h.leftChild; } if( chldPg==0 ){ pCur->iMatch = c; if( pRes ) *pRes = c; return SQLITE_OK; } | | | 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 | chldPg = pPage->apCell[lwr]->h.leftChild; } if( chldPg==0 ){ pCur->iMatch = c; if( pRes ) *pRes = c; return SQLITE_OK; } rc = moveToChild(pCur, SWAB32(pCur->pBt, chldPg)); if( rc ) return rc; } /* NOT REACHED */ } /* ** Advance the cursor to the next entry in the database. If |
︙ | ︙ | |||
1470 1471 1472 1473 1474 1475 1476 | pCur->bSkipNext = 0; if( pRes ) *pRes = 0; return SQLITE_OK; } pCur->idx++; if( pCur->idx>=pCur->pPage->nCell ){ if( pCur->pPage->u.hdr.rightChild ){ | | | 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 | pCur->bSkipNext = 0; if( pRes ) *pRes = 0; return SQLITE_OK; } pCur->idx++; if( pCur->idx>=pCur->pPage->nCell ){ if( pCur->pPage->u.hdr.rightChild ){ rc = moveToChild(pCur, SWAB32(pCur->pBt, pCur->pPage->u.hdr.rightChild)); if( rc ) return rc; rc = moveToLeftmost(pCur); if( rc ) return rc; if( pRes ) *pRes = 0; return SQLITE_OK; } do{ |
︙ | ︙ | |||
1520 1521 1522 1523 1524 1525 1526 | int rc; if( pPage1->freeList ){ OverflowPage *pOvfl; FreelistInfo *pInfo; rc = sqlitepager_write(pPage1); if( rc ) return rc; | | | > | | > | | | | | | | | 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 | int rc; if( pPage1->freeList ){ OverflowPage *pOvfl; FreelistInfo *pInfo; rc = sqlitepager_write(pPage1); if( rc ) return rc; SWAB_ADD(pBt, pPage1->nFree, -1); rc = sqlitepager_get(pBt->pPager, SWAB32(pBt, pPage1->freeList), (void**)&pOvfl); if( rc ) return rc; rc = sqlitepager_write(pOvfl); if( rc ){ sqlitepager_unref(pOvfl); return rc; } pInfo = (FreelistInfo*)pOvfl->aPayload; if( pInfo->nFree==0 ){ *pPgno = SWAB32(pBt, pPage1->freeList); pPage1->freeList = pOvfl->iNext; *ppPage = (MemPage*)pOvfl; }else{ int closest, n; n = SWAB32(pBt, pInfo->nFree); if( n>1 && nearby>0 ){ int i, dist; closest = 0; dist = SWAB32(pBt, pInfo->aFree[0]) - nearby; if( dist<0 ) dist = -dist; for(i=1; i<n; i++){ int d2 = SWAB32(pBt, pInfo->aFree[i]) - nearby; if( d2<0 ) d2 = -d2; if( d2<dist ) closest = i; } }else{ closest = 0; } SWAB_ADD(pBt, pInfo->nFree, -1); *pPgno = SWAB32(pBt, pInfo->aFree[closest]); pInfo->aFree[closest] = pInfo->aFree[n-1]; rc = sqlitepager_get(pBt->pPager, *pPgno, (void**)ppPage); sqlitepager_unref(pOvfl); if( rc==SQLITE_OK ){ sqlitepager_dont_rollback(*ppPage); rc = sqlitepager_write(*ppPage); } } |
︙ | ︙ | |||
1595 1596 1597 1598 1599 1600 1601 | sqlitepager_unref(pMemPage->pParent); pMemPage->pParent = 0; } rc = sqlitepager_write(pPage1); if( rc ){ return rc; } | | | | > > | | | | | | | | 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 | sqlitepager_unref(pMemPage->pParent); pMemPage->pParent = 0; } rc = sqlitepager_write(pPage1); if( rc ){ return rc; } SWAB_ADD(pBt, pPage1->nFree, 1); if( pPage1->nFree!=0 && pPage1->freeList!=0 ){ OverflowPage *pFreeIdx; rc = sqlitepager_get(pBt->pPager, SWAB32(pBt, pPage1->freeList), (void**)&pFreeIdx); if( rc==SQLITE_OK ){ FreelistInfo *pInfo = (FreelistInfo*)pFreeIdx->aPayload; int n = SWAB32(pBt, pInfo->nFree); if( n<(sizeof(pInfo->aFree)/sizeof(pInfo->aFree[0])) ){ rc = sqlitepager_write(pFreeIdx); if( rc==SQLITE_OK ){ pInfo->aFree[n] = SWAB32(pBt, pgno); SWAB_ADD(pBt, pInfo->nFree, 1); sqlitepager_unref(pFreeIdx); sqlitepager_dont_write(pBt->pPager, pgno); return rc; } } sqlitepager_unref(pFreeIdx); } } if( pOvfl==0 ){ assert( pgno>0 ); rc = sqlitepager_get(pBt->pPager, pgno, (void**)&pOvfl); if( rc ) return rc; needUnref = 1; } rc = sqlitepager_write(pOvfl); if( rc ){ if( needUnref ) sqlitepager_unref(pOvfl); return rc; } pOvfl->iNext = pPage1->freeList; pPage1->freeList = SWAB32(pBt, pgno); memset(pOvfl->aPayload, 0, OVERFLOW_SIZE); if( needUnref ) rc = sqlitepager_unref(pOvfl); return rc; } /* ** Erase all the data out of a cell. This involves returning overflow ** pages back the freelist. */ static int clearCell(Btree *pBt, Cell *pCell){ Pager *pPager = pBt->pPager; OverflowPage *pOvfl; Pgno ovfl, nextOvfl; int rc; if( NKEY(pBt, pCell->h) + NDATA(pBt, pCell->h) <= MX_LOCAL_PAYLOAD ){ return SQLITE_OK; } ovfl = SWAB32(pBt, pCell->ovfl); pCell->ovfl = 0; while( ovfl ){ rc = sqlitepager_get(pPager, ovfl, (void**)&pOvfl); if( rc ) return rc; nextOvfl = SWAB32(pBt, pOvfl->iNext); rc = freePage(pBt, pOvfl, ovfl); if( rc ) return rc; sqlitepager_unref(pOvfl); ovfl = nextOvfl; } return SQLITE_OK; } |
︙ | ︙ | |||
1679 1680 1681 1682 1683 1684 1685 | int n, rc; int nPayload; const char *pPayload; char *pSpace; Pgno nearby = 0; pCell->h.leftChild = 0; | | | | 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 | int n, rc; int nPayload; const char *pPayload; char *pSpace; Pgno nearby = 0; pCell->h.leftChild = 0; pCell->h.nKey = SWAB16(pBt, nKey & 0xffff); pCell->h.nKeyHi = nKey >> 16; pCell->h.nData = SWAB16(pBt, nData & 0xffff); pCell->h.nDataHi = nData >> 16; pCell->h.iNext = 0; pNext = &pCell->ovfl; pSpace = pCell->aPayload; spaceLeft = MX_LOCAL_PAYLOAD; pPayload = pKey; |
︙ | ︙ | |||
1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 | nearby = *pNext; } if( pPrior ) sqlitepager_unref(pPrior); if( rc ){ clearCell(pBt, pCell); return rc; } pPrior = pOvfl; spaceLeft = OVERFLOW_SIZE; pSpace = pOvfl->aPayload; pNext = &pOvfl->iNext; } n = nPayload; if( n>spaceLeft ) n = spaceLeft; | > | 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 | nearby = *pNext; } if( pPrior ) sqlitepager_unref(pPrior); if( rc ){ clearCell(pBt, pCell); return rc; } if( pBt->needSwab ) *pNext = swab32(*pNext); pPrior = pOvfl; spaceLeft = OVERFLOW_SIZE; pSpace = pOvfl->aPayload; pNext = &pOvfl->iNext; } n = nPayload; if( n>spaceLeft ) n = spaceLeft; |
︙ | ︙ | |||
1760 1761 1762 1763 1764 1765 1766 | ** Reparent all children of the given page to be the given page. ** In other words, for every child of pPage, invoke reparentPage() ** to make sure that each child knows that pPage is its parent. ** ** This routine gets called after you memcpy() one page into ** another. */ | | > | | | | | | | | | | | 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 | ** Reparent all children of the given page to be the given page. ** In other words, for every child of pPage, invoke reparentPage() ** to make sure that each child knows that pPage is its parent. ** ** This routine gets called after you memcpy() one page into ** another. */ static void reparentChildPages(Btree *pBt, MemPage *pPage){ int i; Pager *pPager = pBt->pPager; for(i=0; i<pPage->nCell; i++){ reparentPage(pPager, SWAB32(pBt, pPage->apCell[i]->h.leftChild), pPage); } reparentPage(pPager, SWAB32(pBt, pPage->u.hdr.rightChild), pPage); } /* ** Remove the i-th cell from pPage. This routine effects pPage only. ** The cell content is not freed or deallocated. It is assumed that ** the cell content has been copied someplace else. This routine just ** removes the reference to the cell from pPage. ** ** "sz" must be the number of bytes in the cell. ** ** Do not bother maintaining the integrity of the linked list of Cells. ** Only the pPage->apCell[] array is important. The relinkCellList() ** routine will be called soon after this routine in order to rebuild ** the linked list. */ static void dropCell(Btree *pBt, MemPage *pPage, int idx, int sz){ int j; assert( idx>=0 && idx<pPage->nCell ); assert( sz==cellSize(pBt, pPage->apCell[idx]) ); assert( sqlitepager_iswriteable(pPage) ); freeSpace(pBt, pPage, Addr(pPage->apCell[idx]) - Addr(pPage), sz); for(j=idx; j<pPage->nCell-1; j++){ pPage->apCell[j] = pPage->apCell[j+1]; } pPage->nCell--; } /* ** Insert a new cell on pPage at cell index "i". pCell points to the ** content of the cell. ** ** If the cell content will fit on the page, then put it there. If it ** will not fit, then just make pPage->apCell[i] point to the content ** and set pPage->isOverfull. ** ** Do not bother maintaining the integrity of the linked list of Cells. ** Only the pPage->apCell[] array is important. The relinkCellList() ** routine will be called soon after this routine in order to rebuild ** the linked list. */ static void insertCell(Btree *pBt, MemPage *pPage, int i, Cell *pCell, int sz){ int idx, j; assert( i>=0 && i<=pPage->nCell ); assert( sz==cellSize(pBt, pCell) ); assert( sqlitepager_iswriteable(pPage) ); idx = allocateSpace(pBt, pPage, sz); for(j=pPage->nCell; j>i; j--){ pPage->apCell[j] = pPage->apCell[j-1]; } pPage->nCell++; if( idx<=0 ){ pPage->isOverfull = 1; pPage->apCell[i] = pCell; }else{ memcpy(&pPage->u.aDisk[idx], pCell, sz); pPage->apCell[i] = (Cell*)&pPage->u.aDisk[idx]; } } /* ** Rebuild the linked list of cells on a page so that the cells ** occur in the order specified by the pPage->apCell[] array. ** Invoke this routine once to repair damage after one or more ** invocations of either insertCell() or dropCell(). */ static void relinkCellList(Btree *pBt, MemPage *pPage){ int i; u16 *pIdx; assert( sqlitepager_iswriteable(pPage) ); pIdx = &pPage->u.hdr.firstCell; for(i=0; i<pPage->nCell; i++){ int idx = Addr(pPage->apCell[i]) - Addr(pPage); assert( idx>0 && idx<SQLITE_PAGE_SIZE ); *pIdx = SWAB16(pBt, idx); pIdx = &pPage->apCell[i]->h.iNext; } *pIdx = 0; } /* ** Make a copy of the contents of pFrom into pTo. The pFrom->apCell[] |
︙ | ︙ | |||
1935 1936 1937 1938 1939 1940 1941 | int iCur; /* apCell[iCur] is the cell of the cursor */ MemPage *pOldCurPage; /* The cursor originally points to this page */ int totalSize; /* Total bytes for all cells */ int subtotal; /* Subtotal of bytes in cells on one page */ int cntNew[4]; /* Index in apCell[] of cell after i-th page */ int szNew[4]; /* Combined size of cells place on i-th page */ MemPage *extraUnref = 0; /* A page that needs to be unref-ed */ | | | | | | | | | 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 | int iCur; /* apCell[iCur] is the cell of the cursor */ MemPage *pOldCurPage; /* The cursor originally points to this page */ int totalSize; /* Total bytes for all cells */ int subtotal; /* Subtotal of bytes in cells on one page */ int cntNew[4]; /* Index in apCell[] of cell after i-th page */ int szNew[4]; /* Combined size of cells place on i-th page */ MemPage *extraUnref = 0; /* A page that needs to be unref-ed */ Pgno pgno, swabPgno; /* Page number */ Cell *apCell[MX_CELL*3+5]; /* All cells from pages being balanceed */ int szCell[MX_CELL*3+5]; /* Local size of all cells */ Cell aTemp[2]; /* Temporary holding area for apDiv[] */ MemPage aOld[3]; /* Temporary copies of pPage and its siblings */ /* ** Return without doing any work if pPage is neither overfull nor ** underfull. */ assert( sqlitepager_iswriteable(pPage) ); if( !pPage->isOverfull && pPage->nFree<SQLITE_PAGE_SIZE/2 && pPage->nCell>=2){ relinkCellList(pBt, pPage); return SQLITE_OK; } /* ** Find the parent of the page to be balanceed. ** If there is no parent, it means this page is the root page and ** special rules apply. */ pParent = pPage->pParent; if( pParent==0 ){ Pgno pgnoChild; MemPage *pChild; assert( pPage->isInit ); if( pPage->nCell==0 ){ if( pPage->u.hdr.rightChild ){ /* ** The root page is empty. Copy the one child page ** into the root page and return. This reduces the depth ** of the BTree by one. */ pgnoChild = SWAB32(pBt, pPage->u.hdr.rightChild); rc = sqlitepager_get(pBt->pPager, pgnoChild, (void**)&pChild); if( rc ) return rc; memcpy(pPage, pChild, SQLITE_PAGE_SIZE); pPage->isInit = 0; rc = initPage(pBt, pPage, sqlitepager_pagenumber(pPage), 0); assert( rc==SQLITE_OK ); reparentChildPages(pBt, pPage); if( pCur && pCur->pPage==pChild ){ sqlitepager_unref(pChild); pCur->pPage = pPage; sqlitepager_ref(pPage); } freePage(pBt, pChild, pgnoChild); sqlitepager_unref(pChild); }else{ relinkCellList(pBt, pPage); } return SQLITE_OK; } if( !pPage->isOverfull ){ /* It is OK for the root page to be less than half full. */ relinkCellList(pBt, pPage); return SQLITE_OK; } /* ** If we get to here, it means the root page is overfull. ** When this happens, Create a new child page and copy the ** contents of the root into the child. Then make the root ** page an empty page with rightChild pointing to the new |
︙ | ︙ | |||
2018 2019 2020 2021 2022 2023 2024 | pChild->isOverfull = 1; if( pCur && pCur->pPage==pPage ){ sqlitepager_unref(pPage); pCur->pPage = pChild; }else{ extraUnref = pChild; } | | | > | | | 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 | pChild->isOverfull = 1; if( pCur && pCur->pPage==pPage ){ sqlitepager_unref(pPage); pCur->pPage = pChild; }else{ extraUnref = pChild; } zeroPage(pBt, pPage); pPage->u.hdr.rightChild = SWAB32(pBt, pgnoChild); pParent = pPage; pPage = pChild; } rc = sqlitepager_write(pParent); if( rc ) return rc; assert( pParent->isInit ); /* ** Find the Cell in the parent page whose h.leftChild points back ** to pPage. The "idx" variable is the index of that cell. If pPage ** is the rightmost child of pParent then set idx to pParent->nCell */ idx = -1; pgno = sqlitepager_pagenumber(pPage); swabPgno = SWAB32(pBt, pgno); for(i=0; i<pParent->nCell; i++){ if( pParent->apCell[i]->h.leftChild==swabPgno ){ idx = i; break; } } if( idx<0 && pParent->u.hdr.rightChild==swabPgno ){ idx = pParent->nCell; } if( idx<0 ){ return SQLITE_CORRUPT; } /* |
︙ | ︙ | |||
2073 2074 2075 2076 2077 2078 2079 | if( nxDiv<0 ) nxDiv = 0; nDiv = 0; for(i=0, k=nxDiv; i<3; i++, k++){ if( k<pParent->nCell ){ idxDiv[i] = k; apDiv[i] = pParent->apCell[k]; nDiv++; | | | | | 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 | if( nxDiv<0 ) nxDiv = 0; nDiv = 0; for(i=0, k=nxDiv; i<3; i++, k++){ if( k<pParent->nCell ){ idxDiv[i] = k; apDiv[i] = pParent->apCell[k]; nDiv++; pgnoOld[i] = SWAB32(pBt, apDiv[i]->h.leftChild); }else if( k==pParent->nCell ){ pgnoOld[i] = SWAB32(pBt, pParent->u.hdr.rightChild); }else{ break; } rc = sqlitepager_get(pBt->pPager, pgnoOld[i], (void**)&apOld[i]); if( rc ) goto balance_cleanup; rc = initPage(pBt, apOld[i], pgnoOld[i], pParent); if( rc ) goto balance_cleanup; nOld++; } /* ** Set iCur to be the index in apCell[] of the cell that the cursor ** is pointing to. We will need this later on in order to keep the |
︙ | ︙ | |||
2130 2131 2132 2133 2134 2135 2136 | ** into aTemp[] and remove the the divider Cells from pParent. */ nCell = 0; for(i=0; i<nOld; i++){ MemPage *pOld = &aOld[i]; for(j=0; j<pOld->nCell; j++){ apCell[nCell] = pOld->apCell[j]; | | | | | | 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 | ** into aTemp[] and remove the the divider Cells from pParent. */ nCell = 0; for(i=0; i<nOld; i++){ MemPage *pOld = &aOld[i]; for(j=0; j<pOld->nCell; j++){ apCell[nCell] = pOld->apCell[j]; szCell[nCell] = cellSize(pBt, apCell[nCell]); nCell++; } if( i<nOld-1 ){ szCell[nCell] = cellSize(pBt, apDiv[i]); memcpy(&aTemp[i], apDiv[i], szCell[nCell]); apCell[nCell] = &aTemp[i]; dropCell(pBt, pParent, nxDiv, szCell[nCell]); assert( SWAB32(pBt, apCell[nCell]->h.leftChild)==pgnoOld[i] ); apCell[nCell]->h.leftChild = pOld->u.hdr.rightChild; nCell++; } } /* ** Figure out the number of pages needed to hold all nCell cells. |
︙ | ︙ | |||
2194 2195 2196 2197 2198 2199 2200 | apOld[i] = 0; sqlitepager_write(apNew[i]); }else{ rc = allocatePage(pBt, &apNew[i], &pgnoNew[i], pgnoNew[i-1]); if( rc ) goto balance_cleanup; } nNew++; | | | 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 | apOld[i] = 0; sqlitepager_write(apNew[i]); }else{ rc = allocatePage(pBt, &apNew[i], &pgnoNew[i], pgnoNew[i-1]); if( rc ) goto balance_cleanup; } nNew++; zeroPage(pBt, apNew[i]); apNew[i]->isInit = 1; } /* Free any old pages that were not reused as new pages. */ while( i<nOld ){ rc = freePage(pBt, apOld[i], pgnoOld[i]); |
︙ | ︙ | |||
2252 2253 2254 2255 2256 2257 2258 | */ j = 0; for(i=0; i<nNew; i++){ MemPage *pNew = apNew[i]; while( j<cntNew[i] ){ assert( pNew->nFree>=szCell[j] ); if( pCur && iCur==j ){ pCur->pPage = pNew; pCur->idx = pNew->nCell; } | | | | | | | | | | 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 | */ j = 0; for(i=0; i<nNew; i++){ MemPage *pNew = apNew[i]; while( j<cntNew[i] ){ assert( pNew->nFree>=szCell[j] ); if( pCur && iCur==j ){ pCur->pPage = pNew; pCur->idx = pNew->nCell; } insertCell(pBt, pNew, pNew->nCell, apCell[j], szCell[j]); j++; } assert( pNew->nCell>0 ); assert( !pNew->isOverfull ); relinkCellList(pBt, pNew); if( i<nNew-1 && j<nCell ){ pNew->u.hdr.rightChild = apCell[j]->h.leftChild; apCell[j]->h.leftChild = SWAB32(pBt, pgnoNew[i]); if( pCur && iCur==j ){ pCur->pPage = pParent; pCur->idx = nxDiv; } insertCell(pBt, pParent, nxDiv, apCell[j], szCell[j]); j++; nxDiv++; } } assert( j==nCell ); apNew[nNew-1]->u.hdr.rightChild = aOld[nOld-1].u.hdr.rightChild; if( nxDiv==pParent->nCell ){ pParent->u.hdr.rightChild = SWAB32(pBt, pgnoNew[nNew-1]); }else{ pParent->apCell[nxDiv]->h.leftChild = SWAB32(pBt, pgnoNew[nNew-1]); } if( pCur ){ if( j<=iCur && pCur->pPage==pParent && pCur->idx>idxDiv[nOld-1] ){ assert( pCur->pPage==pOldCurPage ); pCur->idx += nNew - nOld; }else{ assert( pOldCurPage!=0 ); sqlitepager_ref(pCur->pPage); sqlitepager_unref(pOldCurPage); } } /* ** Reparent children of all cells. */ for(i=0; i<nNew; i++){ reparentChildPages(pBt, apNew[i]); } reparentChildPages(pBt, pParent); /* ** balance the parent page. */ rc = balance(pBt, pParent, pCur); /* |
︙ | ︙ | |||
2355 2356 2357 2358 2359 2360 2361 | if( rc ) return rc; pPage = pCur->pPage; assert( pPage->isInit ); rc = sqlitepager_write(pPage); if( rc ) return rc; rc = fillInCell(pBt, &newCell, pKey, nKey, pData, nData); if( rc ) return rc; | | | | | 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 | if( rc ) return rc; pPage = pCur->pPage; assert( pPage->isInit ); rc = sqlitepager_write(pPage); if( rc ) return rc; rc = fillInCell(pBt, &newCell, pKey, nKey, pData, nData); if( rc ) return rc; szNew = cellSize(pBt, &newCell); if( loc==0 ){ newCell.h.leftChild = pPage->apCell[pCur->idx]->h.leftChild; rc = clearCell(pBt, pPage->apCell[pCur->idx]); if( rc ) return rc; dropCell(pBt, pPage, pCur->idx, cellSize(pBt, pPage->apCell[pCur->idx])); }else if( loc<0 && pPage->nCell>0 ){ assert( pPage->u.hdr.rightChild==0 ); /* Must be a leaf page */ pCur->idx++; }else{ assert( pPage->u.hdr.rightChild==0 ); /* Must be a leaf page */ } insertCell(pBt, pPage, pCur->idx, &newCell, szNew); rc = balance(pCur->pBt, pPage, pCur); /* sqliteBtreePageDump(pCur->pBt, pCur->pgnoRoot, 1); */ /* fflush(stdout); */ return rc; } /* |
︙ | ︙ | |||
2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 | ** pointing to the first entry after the deleted entry. */ int sqliteBtreeDelete(BtCursor *pCur){ MemPage *pPage = pCur->pPage; Cell *pCell; int rc; Pgno pgnoChild; assert( pPage->isInit ); if( pCur->pPage==0 ){ return SQLITE_ABORT; /* A rollback destroyed this cursor */ } if( !pCur->pBt->inTrans ){ return SQLITE_ERROR; /* Must start a transaction first */ } if( pCur->idx >= pPage->nCell ){ return SQLITE_ERROR; /* The cursor is not pointing to anything */ } if( !pCur->wrFlag ){ return SQLITE_PERM; /* Did not open this cursor for writing */ } rc = sqlitepager_write(pPage); if( rc ) return rc; pCell = pPage->apCell[pCur->idx]; | > | | | | | | | | | | | | 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 | ** pointing to the first entry after the deleted entry. */ int sqliteBtreeDelete(BtCursor *pCur){ MemPage *pPage = pCur->pPage; Cell *pCell; int rc; Pgno pgnoChild; Btree *pBt = pCur->pBt; assert( pPage->isInit ); if( pCur->pPage==0 ){ return SQLITE_ABORT; /* A rollback destroyed this cursor */ } if( !pCur->pBt->inTrans ){ return SQLITE_ERROR; /* Must start a transaction first */ } if( pCur->idx >= pPage->nCell ){ return SQLITE_ERROR; /* The cursor is not pointing to anything */ } if( !pCur->wrFlag ){ return SQLITE_PERM; /* Did not open this cursor for writing */ } rc = sqlitepager_write(pPage); if( rc ) return rc; pCell = pPage->apCell[pCur->idx]; pgnoChild = SWAB32(pBt, pCell->h.leftChild); clearCell(pBt, pCell); if( pgnoChild ){ /* ** The entry we are about to delete is not a leaf so if we do not ** do something we will leave a hole on an internal page. ** We have to fill the hole by moving in a cell from a leaf. The ** next Cell after the one to be deleted is guaranteed to exist and ** to be a leaf so we can use it. */ BtCursor leafCur; Cell *pNext; int szNext; getTempCursor(pCur, &leafCur); rc = sqliteBtreeNext(&leafCur, 0); if( rc!=SQLITE_OK ){ return SQLITE_CORRUPT; } rc = sqlitepager_write(leafCur.pPage); if( rc ) return rc; dropCell(pBt, pPage, pCur->idx, cellSize(pBt, pCell)); pNext = leafCur.pPage->apCell[leafCur.idx]; szNext = cellSize(pBt, pNext); pNext->h.leftChild = SWAB32(pBt, pgnoChild); insertCell(pBt, pPage, pCur->idx, pNext, szNext); rc = balance(pBt, pPage, pCur); if( rc ) return rc; pCur->bSkipNext = 1; dropCell(pBt, leafCur.pPage, leafCur.idx, szNext); rc = balance(pBt, leafCur.pPage, pCur); releaseTempCursor(&leafCur); }else{ dropCell(pBt, pPage, pCur->idx, cellSize(pBt, pCell)); if( pCur->idx>=pPage->nCell ){ pCur->idx = pPage->nCell-1; if( pCur->idx<0 ){ pCur->idx = 0; pCur->bSkipNext = 1; }else{ pCur->bSkipNext = 0; } }else{ pCur->bSkipNext = 1; } rc = balance(pBt, pPage, pCur); } return rc; } /* ** Create a new BTree table. Write into *piTable the page ** number for the root page of the new table. |
︙ | ︙ | |||
2477 2478 2479 2480 2481 2482 2483 | } if( pBt->readOnly ){ return SQLITE_READONLY; } rc = allocatePage(pBt, &pRoot, &pgnoRoot, 0); if( rc ) return rc; assert( sqlitepager_iswriteable(pRoot) ); | | | 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 | } if( pBt->readOnly ){ return SQLITE_READONLY; } rc = allocatePage(pBt, &pRoot, &pgnoRoot, 0); if( rc ) return rc; assert( sqlitepager_iswriteable(pRoot) ); zeroPage(pBt, pRoot); sqlitepager_unref(pRoot); *piTable = (int)pgnoRoot; return SQLITE_OK; } /* ** Create a new BTree index. Write into *piTable the page |
︙ | ︙ | |||
2510 2511 2512 2513 2514 2515 2516 | Cell *pCell; int idx; rc = sqlitepager_get(pBt->pPager, pgno, (void**)&pPage); if( rc ) return rc; rc = sqlitepager_write(pPage); if( rc ) return rc; | | | | | | | | 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 | Cell *pCell; int idx; rc = sqlitepager_get(pBt->pPager, pgno, (void**)&pPage); if( rc ) return rc; rc = sqlitepager_write(pPage); if( rc ) return rc; rc = initPage(pBt, pPage, pgno, 0); if( rc ) return rc; idx = SWAB16(pBt, pPage->u.hdr.firstCell); while( idx>0 ){ pCell = (Cell*)&pPage->u.aDisk[idx]; idx = SWAB16(pBt, pCell->h.iNext); if( pCell->h.leftChild ){ rc = clearDatabasePage(pBt, SWAB32(pBt, pCell->h.leftChild), 1); if( rc ) return rc; } rc = clearCell(pBt, pCell); if( rc ) return rc; } if( pPage->u.hdr.rightChild ){ rc = clearDatabasePage(pBt, SWAB32(pBt, pPage->u.hdr.rightChild), 1); if( rc ) return rc; } if( freePageFlag ){ rc = freePage(pBt, pPage, pgno); }else{ zeroPage(pBt, pPage); } sqlitepager_unref(pPage); return rc; } /* ** Delete all information from a single table in the database. |
︙ | ︙ | |||
2580 2581 2582 2583 2584 2585 2586 | rc = sqlitepager_get(pBt->pPager, (Pgno)iTable, (void**)&pPage); if( rc ) return rc; rc = sqliteBtreeClearTable(pBt, iTable); if( rc ) return rc; if( iTable>2 ){ rc = freePage(pBt, pPage, iTable); }else{ | | > | | > > | | > > | 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 | rc = sqlitepager_get(pBt->pPager, (Pgno)iTable, (void**)&pPage); if( rc ) return rc; rc = sqliteBtreeClearTable(pBt, iTable); if( rc ) return rc; if( iTable>2 ){ rc = freePage(pBt, pPage, iTable); }else{ zeroPage(pBt, pPage); } sqlitepager_unref(pPage); return rc; } /* ** Read the meta-information out of a database file. */ int sqliteBtreeGetMeta(Btree *pBt, int *aMeta){ PageOne *pP1; int rc; int i; rc = sqlitepager_get(pBt->pPager, 1, (void**)&pP1); if( rc ) return rc; aMeta[0] = SWAB32(pBt, pP1->nFree); for(i=0; i<sizeof(pP1->aMeta)/sizeof(pP1->aMeta[0]); i++){ aMeta[i+1] = SWAB32(pBt, pP1->aMeta[i]); } sqlitepager_unref(pP1); return SQLITE_OK; } /* ** Write meta-information back into the database. */ int sqliteBtreeUpdateMeta(Btree *pBt, int *aMeta){ PageOne *pP1; int rc, i; if( !pBt->inTrans ){ return SQLITE_ERROR; /* Must start a transaction first */ } if( pBt->readOnly ){ return SQLITE_READONLY; } pP1 = pBt->page1; rc = sqlitepager_write(pP1); if( rc ) return rc; for(i=0; i<sizeof(pP1->aMeta)/sizeof(pP1->aMeta[0]); i++){ pP1->aMeta[i] = SWAB32(pBt, aMeta[i+1]); } return SQLITE_OK; } /****************************************************************************** ** The complete implementation of the BTree subsystem is above this line. ** All the code the follows is for testing and troubleshooting the BTree ** subsystem. None of the code that follows is used during normal operation. |
︙ | ︙ | |||
2645 2646 2647 2648 2649 2650 2651 | unsigned char payload[20]; rc = sqlitepager_get(pBt->pPager, (Pgno)pgno, (void**)&pPage); if( rc ){ return rc; } if( recursive ) printf("PAGE %d:\n", pgno); i = 0; | | | | | > | | | | | | | | | | | 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 | unsigned char payload[20]; rc = sqlitepager_get(pBt->pPager, (Pgno)pgno, (void**)&pPage); if( rc ){ return rc; } if( recursive ) printf("PAGE %d:\n", pgno); i = 0; idx = SWAB16(pBt, pPage->u.hdr.firstCell); while( idx>0 && idx<=SQLITE_PAGE_SIZE-MIN_CELL_SIZE ){ Cell *pCell = (Cell*)&pPage->u.aDisk[idx]; int sz = cellSize(pBt, pCell); sprintf(range,"%d..%d", idx, idx+sz-1); sz = NKEY(pBt, pCell->h) + NDATA(pBt, pCell->h); if( sz>sizeof(payload)-1 ) sz = sizeof(payload)-1; memcpy(payload, pCell->aPayload, sz); for(j=0; j<sz; j++){ if( payload[j]<0x20 || payload[j]>0x7f ) payload[j] = '.'; } payload[sz] = 0; printf( "cell %2d: i=%-10s chld=%-4d nk=%-4d nd=%-4d payload=%s\n", i, range, (int)pCell->h.leftChild, NKEY(pBt, pCell->h), NDATA(pBt, pCell->h), payload ); if( pPage->isInit && pPage->apCell[i]!=pCell ){ printf("**** apCell[%d] does not match on prior entry ****\n", i); } i++; idx = SWAB16(pBt, pCell->h.iNext); } if( idx!=0 ){ printf("ERROR: next cell index out of range: %d\n", idx); } printf("right_child: %d\n", SWAB32(pBt, pPage->u.hdr.rightChild)); nFree = 0; i = 0; idx = SWAB16(pBt, pPage->u.hdr.firstFree); while( idx>0 && idx<SQLITE_PAGE_SIZE ){ FreeBlk *p = (FreeBlk*)&pPage->u.aDisk[idx]; sprintf(range,"%d..%d", idx, idx+p->iSize-1); nFree += SWAB16(pBt, p->iSize); printf("freeblock %2d: i=%-10s size=%-4d total=%d\n", i, range, SWAB16(pBt, p->iSize), nFree); idx = SWAB16(pBt, p->iNext); i++; } if( idx!=0 ){ printf("ERROR: next freeblock index out of range: %d\n", idx); } if( recursive && pPage->u.hdr.rightChild!=0 ){ idx = SWAB16(pBt, pPage->u.hdr.firstCell); while( idx>0 && idx<SQLITE_PAGE_SIZE-MIN_CELL_SIZE ){ Cell *pCell = (Cell*)&pPage->u.aDisk[idx]; sqliteBtreePageDump(pBt, SWAB32(pBt, pCell->h.leftChild), 1); idx = SWAB16(pBt, pCell->h.iNext); } sqliteBtreePageDump(pBt, SWAB32(pBt, pPage->u.hdr.rightChild), 1); } sqlitepager_unref(pPage); return SQLITE_OK; } #endif #ifdef SQLITE_TEST |
︙ | ︙ | |||
2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 | ** aResult[7] = Page number of the right child for the whole page ** ** This routine is used for testing and debugging only. */ int sqliteBtreeCursorDump(BtCursor *pCur, int *aResult){ int cnt, idx; MemPage *pPage = pCur->pPage; aResult[0] = sqlitepager_pagenumber(pPage); aResult[1] = pCur->idx; aResult[2] = pPage->nCell; if( pCur->idx>=0 && pCur->idx<pPage->nCell ){ | > | | | | | | 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 | ** aResult[7] = Page number of the right child for the whole page ** ** This routine is used for testing and debugging only. */ int sqliteBtreeCursorDump(BtCursor *pCur, int *aResult){ int cnt, idx; MemPage *pPage = pCur->pPage; Btree *pBt = pCur->pBt; aResult[0] = sqlitepager_pagenumber(pPage); aResult[1] = pCur->idx; aResult[2] = pPage->nCell; if( pCur->idx>=0 && pCur->idx<pPage->nCell ){ aResult[3] = cellSize(pBt, pPage->apCell[pCur->idx]); aResult[6] = SWAB32(pBt, pPage->apCell[pCur->idx]->h.leftChild); }else{ aResult[3] = 0; aResult[6] = 0; } aResult[4] = pPage->nFree; cnt = 0; idx = SWAB16(pBt, pPage->u.hdr.firstFree); while( idx>0 && idx<SQLITE_PAGE_SIZE ){ cnt++; idx = SWAB16(pBt, ((FreeBlk*)&pPage->u.aDisk[idx])->iNext); } aResult[5] = cnt; aResult[7] = SWAB32(pBt, pPage->u.hdr.rightChild); return SQLITE_OK; } #endif #ifdef SQLITE_TEST /* ** Return the pager associated with a BTree. This routine is used for |
︙ | ︙ | |||
2835 2836 2837 2838 2839 2840 2841 | if( sqlitepager_get(pCheck->pPager, (Pgno)iPage, (void**)&pOvfl) ){ sprintf(zMsg, "failed to get page %d", iPage); checkAppendMsg(pCheck, zContext, zMsg); break; } if( isFreeList ){ FreelistInfo *pInfo = (FreelistInfo*)pOvfl->aPayload; | > | | | | | 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 | if( sqlitepager_get(pCheck->pPager, (Pgno)iPage, (void**)&pOvfl) ){ sprintf(zMsg, "failed to get page %d", iPage); checkAppendMsg(pCheck, zContext, zMsg); break; } if( isFreeList ){ FreelistInfo *pInfo = (FreelistInfo*)pOvfl->aPayload; int n = SWAB32(pCheck->pBt, pInfo->nFree); for(i=0; i<n; i++){ checkRef(pCheck, SWAB32(pCheck->pBt, pInfo->aFree[i]), zMsg); } N -= n; } iPage = SWAB32(pCheck->pBt, pOvfl->iNext); sqlitepager_unref(pOvfl); } } /* ** Return negative if zKey1<zKey2. ** Return zero if zKey1==zKey2. |
︙ | ︙ | |||
2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 | int nUpper /* Number of characters in zUpperBound */ ){ MemPage *pPage; int i, rc, depth, d2, pgno; char *zKey1, *zKey2; int nKey1, nKey2; BtCursor cur; char zMsg[100]; char zContext[100]; char hit[SQLITE_PAGE_SIZE]; /* Check that the page exists */ if( iPage==0 ) return 0; if( checkRef(pCheck, iPage, zParentContext) ) return 0; sprintf(zContext, "On tree page %d: ", iPage); if( (rc = sqlitepager_get(pCheck->pPager, (Pgno)iPage, (void**)&pPage))!=0 ){ sprintf(zMsg, "unable to get the page. error code=%d", rc); checkAppendMsg(pCheck, zContext, zMsg); return 0; } | > > | < | | | | | | | | | | | | 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 | int nUpper /* Number of characters in zUpperBound */ ){ MemPage *pPage; int i, rc, depth, d2, pgno; char *zKey1, *zKey2; int nKey1, nKey2; BtCursor cur; Btree *pBt; char zMsg[100]; char zContext[100]; char hit[SQLITE_PAGE_SIZE]; /* Check that the page exists */ cur.pBt = pBt = pCheck->pBt; if( iPage==0 ) return 0; if( checkRef(pCheck, iPage, zParentContext) ) return 0; sprintf(zContext, "On tree page %d: ", iPage); if( (rc = sqlitepager_get(pCheck->pPager, (Pgno)iPage, (void**)&pPage))!=0 ){ sprintf(zMsg, "unable to get the page. error code=%d", rc); checkAppendMsg(pCheck, zContext, zMsg); return 0; } if( (rc = initPage(pBt, pPage, (Pgno)iPage, pParent))!=0 ){ sprintf(zMsg, "initPage() returns error code %d", rc); checkAppendMsg(pCheck, zContext, zMsg); sqlitepager_unref(pPage); return 0; } /* Check out all the cells. */ depth = 0; if( zLowerBound ){ zKey1 = sqliteMalloc( nLower+1 ); memcpy(zKey1, zLowerBound, nLower); zKey1[nLower] = 0; }else{ zKey1 = 0; } nKey1 = nLower; cur.pPage = pPage; for(i=0; i<pPage->nCell; i++){ Cell *pCell = pPage->apCell[i]; int sz; /* Check payload overflow pages */ nKey2 = NKEY(pBt, pCell->h); sz = nKey2 + NDATA(pBt, pCell->h); sprintf(zContext, "On page %d cell %d: ", iPage, i); if( sz>MX_LOCAL_PAYLOAD ){ int nPage = (sz - MX_LOCAL_PAYLOAD + OVERFLOW_SIZE - 1)/OVERFLOW_SIZE; checkList(pCheck, 0, SWAB32(pBt, pCell->ovfl), nPage, zContext); } /* Check that keys are in the right order */ cur.idx = i; zKey2 = sqliteMalloc( nKey2+1 ); getPayload(&cur, 0, nKey2, zKey2); if( zKey1 && keyCompare(zKey1, nKey1, zKey2, nKey2)>=0 ){ checkAppendMsg(pCheck, zContext, "Key is out of order"); } /* Check sanity of left child page. */ pgno = SWAB32(pBt, pCell->h.leftChild); d2 = checkTreePage(pCheck, pgno, pPage, zContext, zKey1,nKey1,zKey2,nKey2); if( i>0 && d2!=depth ){ checkAppendMsg(pCheck, zContext, "Child page depth differs"); } depth = d2; sqliteFree(zKey1); zKey1 = zKey2; nKey1 = nKey2; } pgno = SWAB32(pBt, pPage->u.hdr.rightChild); sprintf(zContext, "On page %d at right child: ", iPage); checkTreePage(pCheck, pgno, pPage, zContext, zKey1,nKey1,zUpperBound,nUpper); sqliteFree(zKey1); /* Check for complete coverage of the page */ memset(hit, 0, sizeof(hit)); memset(hit, 1, sizeof(PageHdr)); for(i=SWAB16(pBt, pPage->u.hdr.firstCell); i>0 && i<SQLITE_PAGE_SIZE; ){ Cell *pCell = (Cell*)&pPage->u.aDisk[i]; int j; for(j=i+cellSize(pBt, pCell)-1; j>=i; j--) hit[j]++; i = SWAB16(pBt, pCell->h.iNext); } for(i=SWAB16(pBt,pPage->u.hdr.firstFree); i>0 && i<SQLITE_PAGE_SIZE; ){ FreeBlk *pFBlk = (FreeBlk*)&pPage->u.aDisk[i]; int j; for(j=i+SWAB16(pBt,pFBlk->iSize)-1; j>=i; j--) hit[j]++; i = SWAB16(pBt,pFBlk->iNext); } for(i=0; i<SQLITE_PAGE_SIZE; i++){ if( hit[i]==0 ){ sprintf(zMsg, "Unused space at byte %d of page %d", i, iPage); checkAppendMsg(pCheck, zMsg, 0); break; }else if( hit[i]>1 ){ |
︙ | ︙ | |||
3049 3050 3051 3052 3053 3054 3055 | sCheck.anRef = sqliteMalloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) ); sCheck.anRef[1] = 1; for(i=2; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; } sCheck.zErrMsg = 0; /* Check the integrity of the freelist */ | | | | 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 | sCheck.anRef = sqliteMalloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) ); sCheck.anRef[1] = 1; for(i=2; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; } sCheck.zErrMsg = 0; /* Check the integrity of the freelist */ checkList(&sCheck, 1, SWAB32(pBt, pBt->page1->freeList), SWAB32(pBt, pBt->page1->nFree), "Main freelist: "); /* Check all the tables. */ for(i=0; i<nRoot; i++){ if( aRoot[i]==0 ) continue; checkTreePage(&sCheck, aRoot[i], 0, "List of tree roots: ", 0,0,0,0); } |
︙ | ︙ |
Changes to src/btree.h.
︙ | ︙ | |||
9 10 11 12 13 14 15 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the sqlite B-Tree file ** subsystem. See comments in the source code for a detailed description ** of what each interface routine does. ** | | | 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the sqlite B-Tree file ** subsystem. See comments in the source code for a detailed description ** of what each interface routine does. ** ** @(#) $Id: btree.h,v 1.25 2002/08/11 20:10:48 drh Exp $ */ #ifndef _BTREE_H_ #define _BTREE_H_ typedef struct Btree Btree; typedef struct BtCursor BtCursor; |
︙ | ︙ | |||
59 60 61 62 63 64 65 66 67 68 | char *sqliteBtreeIntegrityCheck(Btree*, int*, int); #ifdef SQLITE_TEST int sqliteBtreePageDump(Btree*, int, int); int sqliteBtreeCursorDump(BtCursor*, int*); struct Pager *sqliteBtreePager(Btree*); #endif #endif /* _BTREE_H_ */ | > | 59 60 61 62 63 64 65 66 67 68 69 | char *sqliteBtreeIntegrityCheck(Btree*, int*, int); #ifdef SQLITE_TEST int sqliteBtreePageDump(Btree*, int, int); int sqliteBtreeCursorDump(BtCursor*, int*); struct Pager *sqliteBtreePager(Btree*); int btree_native_byte_order; #endif #endif /* _BTREE_H_ */ |
Changes to src/parse.y.
︙ | ︙ | |||
10 11 12 13 14 15 16 | ** ************************************************************************* ** This file contains SQLite's grammar for SQL. Process this file ** using the lemon parser generator to generate C code that runs ** the parser. Lemon will also generate a header file containing ** numeric codes for all of the tokens. ** | | | 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | ** ************************************************************************* ** This file contains SQLite's grammar for SQL. Process this file ** using the lemon parser generator to generate C code that runs ** the parser. Lemon will also generate a header file containing ** numeric codes for all of the tokens. ** ** @(#) $Id: parse.y,v 1.80 2002/08/11 20:10:48 drh Exp $ */ %token_prefix TK_ %token_type {Token} %default_type {Token} %extra_argument {Parse *pParse} %syntax_error { sqliteSetString(&pParse->zErrMsg,"syntax error",0); |
︙ | ︙ | |||
160 161 162 163 164 165 166 167 168 169 170 171 172 173 | carg ::= DEFAULT PLUS FLOAT(X). {sqliteAddDefaultValue(pParse,&X,0);} carg ::= DEFAULT MINUS FLOAT(X). {sqliteAddDefaultValue(pParse,&X,1);} carg ::= DEFAULT NULL. // In addition to the type name, we also care about the primary key and // UNIQUE constraints. // ccons ::= NOT NULL onconf(R). {sqliteAddNotNull(pParse, R);} ccons ::= PRIMARY KEY sortorder onconf(R). {sqliteAddPrimaryKey(pParse,0,R);} ccons ::= UNIQUE onconf(R). {sqliteCreateIndex(pParse,0,0,0,R,0,0);} ccons ::= CHECK LP expr RP onconf. ccons ::= references. ccons ::= defer_subclause. ccons ::= COLLATE id(C). { | > | 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 | carg ::= DEFAULT PLUS FLOAT(X). {sqliteAddDefaultValue(pParse,&X,0);} carg ::= DEFAULT MINUS FLOAT(X). {sqliteAddDefaultValue(pParse,&X,1);} carg ::= DEFAULT NULL. // In addition to the type name, we also care about the primary key and // UNIQUE constraints. // ccons ::= NULL onconf. ccons ::= NOT NULL onconf(R). {sqliteAddNotNull(pParse, R);} ccons ::= PRIMARY KEY sortorder onconf(R). {sqliteAddPrimaryKey(pParse,0,R);} ccons ::= UNIQUE onconf(R). {sqliteCreateIndex(pParse,0,0,0,R,0,0);} ccons ::= CHECK LP expr RP onconf. ccons ::= references. ccons ::= defer_subclause. ccons ::= COLLATE id(C). { |
︙ | ︙ |
Changes to src/test3.c.
︙ | ︙ | |||
9 10 11 12 13 14 15 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** Code for testing the btree.c module in SQLite. This code ** is not included in the SQLite library. It is used for automated ** testing of the SQLite library. ** | | | 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** Code for testing the btree.c module in SQLite. This code ** is not included in the SQLite library. It is used for automated ** testing of the SQLite library. ** ** $Id: test3.c,v 1.18 2002/08/11 20:10:48 drh Exp $ */ #include "sqliteInt.h" #include "pager.h" #include "btree.h" #include "tcl.h" #include <stdlib.h> #include <string.h> |
︙ | ︙ | |||
492 493 494 495 496 497 498 | aRoot = malloc( sizeof(int)*(argc-2) ); for(i=0; i<argc-2; i++){ if( Tcl_GetInt(interp, argv[i+2], &aRoot[i]) ) return TCL_ERROR; } zResult = sqliteBtreeIntegrityCheck(pBt, aRoot, nRoot); if( zResult ){ Tcl_AppendResult(interp, zResult, 0); | | | 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 | aRoot = malloc( sizeof(int)*(argc-2) ); for(i=0; i<argc-2; i++){ if( Tcl_GetInt(interp, argv[i+2], &aRoot[i]) ) return TCL_ERROR; } zResult = sqliteBtreeIntegrityCheck(pBt, aRoot, nRoot); if( zResult ){ Tcl_AppendResult(interp, zResult, 0); sqliteFree(zResult); } return TCL_OK; } /* ** Usage: btree_cursor ID TABLENUM WRITEABLE ** |
︙ | ︙ | |||
901 902 903 904 905 906 907 908 909 910 | Tcl_CreateCommand(interp, "btree_key", btree_key, 0, 0); Tcl_CreateCommand(interp, "btree_data", btree_data, 0, 0); Tcl_CreateCommand(interp, "btree_payload_size", btree_payload_size, 0, 0); Tcl_CreateCommand(interp, "btree_first", btree_first, 0, 0); Tcl_CreateCommand(interp, "btree_cursor_dump", btree_cursor_dump, 0, 0); Tcl_CreateCommand(interp, "btree_integrity_check", btree_integrity_check,0,0); Tcl_LinkVar(interp, "pager_refinfo_enable", (char*)&pager_refinfo_enable, TCL_LINK_INT); return TCL_OK; } | > > | 901 902 903 904 905 906 907 908 909 910 911 912 | Tcl_CreateCommand(interp, "btree_key", btree_key, 0, 0); Tcl_CreateCommand(interp, "btree_data", btree_data, 0, 0); Tcl_CreateCommand(interp, "btree_payload_size", btree_payload_size, 0, 0); Tcl_CreateCommand(interp, "btree_first", btree_first, 0, 0); Tcl_CreateCommand(interp, "btree_cursor_dump", btree_cursor_dump, 0, 0); Tcl_CreateCommand(interp, "btree_integrity_check", btree_integrity_check,0,0); Tcl_LinkVar(interp, "pager_refinfo_enable", (char*)&pager_refinfo_enable, TCL_LINK_INT); Tcl_LinkVar(interp, "btree_native_byte_order",(char*)&btree_native_byte_order, TCL_LINK_INT); return TCL_OK; } |
Changes to test/all.test.
1 2 3 4 5 6 7 8 9 10 11 12 | # 2001 September 15 # # The author disclaims copyright to this source code. In place of # a legal notice, here is a blessing: # # May you do good and not evil. # May you find forgiveness for yourself and forgive others. # May you share freely, never taking more than you give. # #*********************************************************************** # This file runs all tests. # | | | > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 | # 2001 September 15 # # The author disclaims copyright to this source code. In place of # a legal notice, here is a blessing: # # May you do good and not evil. # May you find forgiveness for yourself and forgive others. # May you share freely, never taking more than you give. # #*********************************************************************** # This file runs all tests. # # $Id: all.test,v 1.16 2002/08/11 20:10:49 drh Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl rename finish_test really_finish_test proc finish_test {} {memleak_check} if {[file exists ./sqlite_test_count]} { set COUNT [exec cat ./sqlite_test_count] } else { set COUNT 4 } # LeakList will hold a list of the number of unfreed mallocs after # each round of the test. This number should be constant. If it # grows, it may mean there is a memory leak in the library. # set LeakList {} set EXCLUDE { all.test quick.test malloc.test misuse.test } # btree2.test for {set Counter 0} {$Counter<$COUNT && $nErr==0} {incr Counter} { set btree_native_byte_order [expr {($Counter>>1)&0x1}] if {$Counter%2} { set ::SETUP_SQL {PRAGMA default_synchronous=off;} } else { catch {unset ::SETUP_SQL} } foreach testfile [lsort -dictionary [glob $testdir/*.test]] { set tail [file tail $testfile] |
︙ | ︙ |
Changes to test/version.test.
︙ | ︙ | |||
8 9 10 11 12 13 14 | # May you share freely, never taking more than you give. # #*********************************************************************** # This file implements regression tests for SQLite library. The # focus of this file is testing the ability of the library to detect # past or future file format version numbers and respond appropriately. # | | | 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 | # May you share freely, never taking more than you give. # #*********************************************************************** # This file implements regression tests for SQLite library. The # focus of this file is testing the ability of the library to detect # past or future file format version numbers and respond appropriately. # # $Id: version.test,v 1.5 2002/08/11 20:10:49 drh Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl # Current file format version set VX 3 |
︙ | ︙ | |||
34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 | } {1 2 3 4 5 6 7 8} # Make sure the version number is set correctly # do_test version-1.2 { db close set ::bt [btree_open test.db] set ::meta [btree_get_meta $::bt] lindex $::meta 2 } $VX # Increase the file_format number by one. Verify that the # file will refuse to open. # do_test version-1.3 { | > > | 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 | } {1 2 3 4 5 6 7 8} # Make sure the version number is set correctly # do_test version-1.2 { db close set ::bt [btree_open test.db] btree_begin_transaction $::bt set ::meta [btree_get_meta $::bt] btree_rollback $::bt lindex $::meta 2 } $VX # Increase the file_format number by one. Verify that the # file will refuse to open. # do_test version-1.3 { |
︙ | ︙ |
Changes to www/faq.tcl.
1 2 3 | # # Run this script to generated a faq.html output file # | | | 1 2 3 4 5 6 7 8 9 10 11 | # # Run this script to generated a faq.html output file # set rcsid {$Id: faq.tcl,v 1.14 2002/08/11 20:10:49 drh Exp $} puts {<html> <head> <title>SQLite Frequently Asked Questions</title> </head> <body bgcolor="white"> <h1 align="center">Frequently Asked Questions</h1> |
︙ | ︙ | |||
149 150 151 152 153 154 155 156 157 158 | </ol> } faq { My linux box is not able to read an SQLite database that was created on my SparcStation. } { <p>The x86 processor on your linux box is little-endian (meaning that the least significant byte of integers comes first) but the Sparc is big-endian (the most significant bytes comes first). SQLite databases | > > | | | < < < < | < < < < < < < < < | 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 | </ol> } faq { My linux box is not able to read an SQLite database that was created on my SparcStation. } { <p>You need to upgrade your SQLite library to version 2.6.3 or later.</p> <p>The x86 processor on your linux box is little-endian (meaning that the least significant byte of integers comes first) but the Sparc is big-endian (the most significant bytes comes first). SQLite databases created on a little-endian architecture cannot be on a big-endian machine by version 2.6.2 or earlier of SQLite. Beginning with version 2.6.3, SQLite should be able to read and write database files regardless of byte order of the machine on which the file was created.</p> } faq { Can multiple applications or multiple instances of the same application access a single database file at the same time? } { <p>Multiple processes can have the same database open at the same |
︙ | ︙ |
Changes to www/index.tcl.
1 2 3 | # # Run this TCL script to generate HTML for the index.html file. # | | | 1 2 3 4 5 6 7 8 9 10 11 | # # Run this TCL script to generate HTML for the index.html file. # set rcsid {$Id: index.tcl,v 1.61 2002/08/11 20:10:49 drh Exp $} puts {<html> <head><title>SQLite: An SQL Database Engine In A C Library</title></head> <body bgcolor=white> <h1 align=center>SQLite: An SQL Database Engine In A C Library</h1> <p align=center>} puts "This page was last modified on [lrange $rcsid 3 4] UTC<br>" |
︙ | ︙ | |||
45 46 47 48 49 50 51 | } puts {<h2>Features</h2> <p><ul> <li>Implements most of SQL92.</li> <li>A complete database (with multiple tables and indices) is | | | 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 | } puts {<h2>Features</h2> <p><ul> <li>Implements most of SQL92.</li> <li>A complete database (with multiple tables and indices) is stored in a single byte-order independent disk file.</li> <li>Atomic commit and rollback protect data integrity.</li> <li>Small memory footprint: less than 20K lines of C code.</li> <li><a href="speed.html">Four times faster</a> than PostgreSQL. Twice as fast as SQLite 1.0.</li> <li>Very simple <a href="c_interface.html">C/C++ interface</a> requires the use of only three functions and one opaque structure.</li> |
︙ | ︙ |
Changes to www/opcode.tcl.
1 2 3 | # # Run this Tcl script to generate the sqlite.html file. # | | | 1 2 3 4 5 6 7 8 9 10 11 | # # Run this Tcl script to generate the sqlite.html file. # set rcsid {$Id: opcode.tcl,v 1.10 2002/08/11 20:10:49 drh Exp $} puts {<html> <head> <title>SQLite Virtual Machine Opcodes</title> </head> <body bgcolor=white> <h1 align=center> |
︙ | ︙ | |||
87 88 89 90 91 92 93 | Execution continues until (1) a Halt instruction is seen, or (2) the program counter becomes one greater than the address of last instruction, or (3) there is an execution error. When the virtual machine halts, all memory that it allocated is released and all database cursors it may have had open are closed. If the execution stopped due to an error, any pending transactions are terminated and changes made | | | 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 | Execution continues until (1) a Halt instruction is seen, or (2) the program counter becomes one greater than the address of last instruction, or (3) there is an execution error. When the virtual machine halts, all memory that it allocated is released and all database cursors it may have had open are closed. If the execution stopped due to an error, any pending transactions are terminated and changes made to the database are rolled back.</p> <p>The virtual machine also contains an operand stack of unlimited depth. Many of the opcodes use operands from the stack. See the individual opcode descriptions for details.</p> <p>The virtual machine can have zero or more cursors. Each cursor is a pointer into a single table or index within the database. |
︙ | ︙ |