Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
Comment: | Add a prototype JSON parser. |
---|---|
Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | json |
Files: | files | file ages | folders |
SHA1: |
789ba487000aa73621a41d115ad5de45 |
User & Date: | drh 2015-08-15 21:25:37.000 |
Context
2015-08-15
| ||
21:29 | Fix off-by-one error when parsing primitive JSON types "true", "false", and "null". (check-in: 42c15c1e36 user: drh tags: json) | |
21:25 | Add a prototype JSON parser. (check-in: 789ba48700 user: drh tags: json) | |
2015-08-13
| ||
13:54 | Experimental code (untested) for a JSONB datatype. (check-in: e3596ac7b1 user: drh tags: json) | |
Changes
Changes to ext/misc/json.c.
︙ | ︙ | |||
73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 | ** If A0 is 250 or more then the value is a (A0-247)-byte big-endian ** integer taken from starting at A1. */ #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 #include <assert.h> #include <string.h> /* Unsigned integer types */ typedef sqlite3_uint64 u64; typedef unsigned int u32; typedef unsigned char u8; /* An instance of this object represents a JSON string or ** JSONB blob under construction. */ typedef struct Json Json; struct Json { sqlite3_context *pCtx; /* Function context - put error messages here */ char *zBuf; /* Append JSON or JSONB content here */ u64 nAlloc; /* Bytes of storage available in zBuf[] */ u64 nUsed; /* Bytes of zBuf[] currently used */ u8 bStatic; /* True if zBuf is static space */ | > | | | | | | | | | | > > > > > > > > > > > > > > > > > > > > > | 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 | ** If A0 is 250 or more then the value is a (A0-247)-byte big-endian ** integer taken from starting at A1. */ #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 #include <assert.h> #include <string.h> #include <ctype.h> /* Unsigned integer types */ typedef sqlite3_uint64 u64; typedef unsigned int u32; typedef unsigned char u8; /* An instance of this object represents a JSON string or ** JSONB blob under construction. */ typedef struct Json Json; struct Json { sqlite3_context *pCtx; /* Function context - put error messages here */ char *zBuf; /* Append JSON or JSONB content here */ u64 nAlloc; /* Bytes of storage available in zBuf[] */ u64 nUsed; /* Bytes of zBuf[] currently used */ u8 bStatic; /* True if zBuf is static space */ u8 oom; /* True if an OOM has been encountered */ char zSpace[100]; /* Initial static space */ }; /* JSON type values */ #define JSON_NULL 0 #define JSON_TRUE 1 #define JSON_FALSE 2 #define JSON_INT 3 #define JSON_REAL 4 #define JSON_STRING 5 #define JSON_ARRAY 6 #define JSON_OBJECT 7 /* A single node of parsed JSON */ typedef struct JsonNode JsonNode; struct JsonNode { u32 eType; /* One of the JSON_ type values */ u32 n; /* Bytes of content, or number of sub-nodes */ const char *zContent; /* Content for JSON_INT, JSON_REAL, or JSON_STRING */ }; /* A completely parsed JSON string */ typedef struct JsonParse JsonParse; struct JsonParse { u32 nNode; /* Number of slots of aNode[] used */ u32 nAlloc; /* Number of slots of aNode[] allocated */ JsonNode *aNode; /* Array of nodes containing the parse */ const char *zJson; /* Original JSON string */ u8 oom; /* Set to true if out of memory */ }; #if 0 /* ** Decode the varint in the first n bytes z[]. Write the integer value ** into *pResult and return the number of bytes in the varint. ** ** If the decode fails because there are not enough bytes in z[] then |
︙ | ︙ | |||
173 174 175 176 177 178 179 | p->bStatic = 1; } /* Initialize the Json object */ static void jsonInit(Json *p, sqlite3_context *pCtx){ p->pCtx = pCtx; | | | | | 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 | p->bStatic = 1; } /* Initialize the Json object */ static void jsonInit(Json *p, sqlite3_context *pCtx){ p->pCtx = pCtx; p->oom = 0; jsonZero(p); } /* Free all allocated memory and reset the Json object back to its ** initial state. */ static void jsonReset(Json *p){ if( !p->bStatic ) sqlite3_free(p->zBuf); jsonZero(p); } /* Report an out-of-memory (OOM) condition */ static void jsonOom(Json *p){ p->oom = 1; sqlite3_result_error_nomem(p->pCtx); jsonReset(p); } /* Enlarge pJson->zBuf so that it can hold at least N more bytes. ** Return zero on success. Return non-zero on an OOM error */ static int jsonGrow(Json *p, u32 N){ u64 nTotal = N<p->nAlloc ? p->nAlloc*2 : p->nAlloc+N+100; char *zNew; if( p->bStatic ){ if( p->oom ) return SQLITE_NOMEM; zNew = sqlite3_malloc64(nTotal); if( zNew==0 ){ jsonOom(p); return SQLITE_NOMEM; } memcpy(zNew, p->zBuf, p->nUsed); p->zBuf = zNew; |
︙ | ︙ | |||
230 231 232 233 234 235 236 237 238 239 240 241 242 243 | /* Append N bytes from zIn onto the end of the Json string. */ static void jsonAppendRaw(Json *p, const char *zIn, u32 N){ if( (N+p->nUsed >= p->nAlloc) && jsonGrow(p,N)!=0 ) return; memcpy(p->zBuf+p->nUsed, zIn, N); p->nUsed += N; } /* Append the N-byte string in zIn to the end of the Json string ** under construction. Enclose the string in "..." and escape ** any double-quotes or backslash characters contained within the ** string. */ static void jsonAppendString(Json *p, const char *zIn, u32 N){ | > > > > > > | 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 | /* Append N bytes from zIn onto the end of the Json string. */ static void jsonAppendRaw(Json *p, const char *zIn, u32 N){ if( (N+p->nUsed >= p->nAlloc) && jsonGrow(p,N)!=0 ) return; memcpy(p->zBuf+p->nUsed, zIn, N); p->nUsed += N; } /* Append the zero-terminated string zIn */ static void jsonAppend(Json *p, const char *zIn){ jsonAppendRaw(p, zIn, (u32)strlen(zIn)); } /* Append the N-byte string in zIn to the end of the Json string ** under construction. Enclose the string in "..." and escape ** any double-quotes or backslash characters contained within the ** string. */ static void jsonAppendString(Json *p, const char *zIn, u32 N){ |
︙ | ︙ | |||
339 340 341 342 343 344 345 | if( (p->nUsed+9 > p->nAlloc) && jsonGrow(p,9)!=0 ) return; p->nUsed += jsonPutVarint64(p->zBuf+p->nUsed, X); } /* Make the JSON in p the result of the SQL function. */ static void jsonResult(Json *p){ | | | | 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 | if( (p->nUsed+9 > p->nAlloc) && jsonGrow(p,9)!=0 ) return; p->nUsed += jsonPutVarint64(p->zBuf+p->nUsed, X); } /* Make the JSON in p the result of the SQL function. */ static void jsonResult(Json *p){ if( p->oom==0 ){ sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed, p->bStatic ? SQLITE_TRANSIENT : sqlite3_free, SQLITE_UTF8); jsonZero(p); } assert( p->bStatic ); } /* Make the JSONB in p the result of the SQL function. */ static void jsonbResult(Json *p){ if( p->oom==0 ){ sqlite3_result_blob(p->pCtx, p->zBuf, p->nUsed, p->bStatic ? SQLITE_TRANSIENT : sqlite3_free); jsonZero(p); } assert( p->bStatic ); } |
︙ | ︙ | |||
424 425 426 427 428 429 430 | Json jx; jsonInit(&jx, context); jx.nUsed = 5; for(i=0; i<argc; i++){ switch( sqlite3_value_type(argv[i]) ){ case SQLITE_NULL: { | | | | | 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 | Json jx; jsonInit(&jx, context); jx.nUsed = 5; for(i=0; i<argc; i++){ switch( sqlite3_value_type(argv[i]) ){ case SQLITE_NULL: { jsonAppendVarint(&jx, JSON_NULL); break; } case SQLITE_INTEGER: case SQLITE_FLOAT: { const char *z = (const char*)sqlite3_value_text(argv[i]); u32 n = (u32)sqlite3_value_bytes(argv[i]); jsonAppendRaw(&jx, z, n); break; } case SQLITE_TEXT: { const char *z = (const char*)sqlite3_value_text(argv[i]); u32 n = (u32)sqlite3_value_bytes(argv[i]); jsonAppendVarint(&jx, JSON_STRING + 4*(u64)n); jsonAppendString(&jx, z, n); break; } default: { jsonZero(&jx); sqlite3_result_error(context, "JSON cannot hold BLOB values", -1); return; } } } if( jx.oom==0 ){ jx.zBuf[0] = 251; jsonPutInt32((unsigned char*)(jx.zBuf+1), jx.nUsed-5); jsonbResult(&jx); } } /* |
︙ | ︙ | |||
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 | return; } } } jsonAppendRaw(&jx, "}", 1); jsonResult(&jx); } #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_json_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ int rc = SQLITE_OK; int i; static const struct { const char *zName; int nArg; void (*xFunc)(sqlite3_context*,int,sqlite3_value**); } aFunc[] = { { "json_array", -1, jsonArrayFunc }, { "jsonb_array", -1, jsonbArrayFunc }, { "json_object", -1, jsonObjectFunc }, }; SQLITE_EXTENSION_INIT2(pApi); (void)pzErrMsg; /* Unused parameter */ for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){ rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg, SQLITE_UTF8 | SQLITE_DETERMINISTIC, 0, aFunc[i].xFunc, 0, 0); } return rc; } | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 | return; } } } jsonAppendRaw(&jx, "}", 1); jsonResult(&jx); } /* ** Create a new JsonNode instance based on the arguments and append that ** instance to the JsonParse. Return the index in pParse->aNode[] of the ** new node, or -1 if a memory allocation fails. */ static int jsonParseAddNode( JsonParse *pParse, /* Append the node to this object */ u32 eType, /* Node type */ u32 n, /* Content size or sub-node count */ const char *zContent /* Content */ ){ JsonNode *p; if( pParse->nNode>=pParse->nAlloc ){ u32 nNew; JsonNode *pNew; if( pParse->oom ) return -1; nNew = pParse->nAlloc*2 + 10; if( nNew<=pParse->nNode ){ pParse->oom = 1; return -1; } pNew = sqlite3_realloc(pParse->aNode, sizeof(JsonNode)*nNew); if( pNew==0 ){ pParse->oom = 1; return -1; } pParse->nAlloc = nNew; pParse->aNode = pNew; } p = &pParse->aNode[pParse->nNode]; p->eType = eType; p->n = n; p->zContent = zContent; return pParse->nNode++; } /* ** Parse a single JSON value which begins at pParse->zJson[i]. Return the ** index of the first character past the end of the value parsed. ** ** Return negative for a syntax error. Special cases: return -2 if the ** first non-whitespace character is '}' and return -3 if the first ** non-whitespace character is ']'. */ static int jsonParseValue(JsonParse *pParse, u32 i){ char c; u32 j; u32 iThis; int x; while( isspace(pParse->zJson[i]) ){ i++; } if( (c = pParse->zJson[i])==0 ) return 0; if( c=='{' ){ /* Parse object */ iThis = jsonParseAddNode(pParse, JSON_OBJECT, 0, 0); if( iThis<0 ) return -1; for(j=i+1;;j++){ while( isspace(pParse->zJson[j]) ){ j++; } x = jsonParseValue(pParse, j); if( x<0 ){ if( x==(-2) && pParse->nNode==iThis+1 ) return j+1; return -1; } if( pParse->aNode[pParse->nNode-1].eType!=JSON_STRING ) return -1; j = x; while( isspace(pParse->zJson[j]) ){ j++; } if( pParse->zJson[j]!=':' ) return -1; j++; x = jsonParseValue(pParse, j); if( x<0 ) return -1; j = x; while( isspace(pParse->zJson[j]) ){ j++; } c = pParse->zJson[j]; if( c==',' ) continue; if( c!='}' ) return -1; break; } pParse->aNode[iThis].n = pParse->nNode - iThis - 1; return j+1; }else if( c=='[' ){ /* Parse array */ iThis = jsonParseAddNode(pParse, JSON_ARRAY, 0, 0); if( iThis<0 ) return -1; for(j=i+1;;j++){ while( isspace(pParse->zJson[j]) ){ j++; } x = jsonParseValue(pParse, j); if( x<0 ){ if( x==(-3) && pParse->nNode==iThis+1 ) return j+1; return -1; } j = x; while( isspace(pParse->zJson[j]) ){ j++; } c = pParse->zJson[j]; if( c==',' ) continue; if( c!=']' ) return -1; break; } pParse->aNode[iThis].n = pParse->nNode - iThis - 1; return j+1; }else if( c=='"' ){ /* Parse string */ j = i+1; for(;;){ c = pParse->zJson[j]; if( c==0 ) return -1; if( c=='\\' ){ c = pParse->zJson[++j]; if( c==0 ) return -1; }else if( c=='"' ){ break; } j++; } jsonParseAddNode(pParse, JSON_STRING, j+1-i, &pParse->zJson[i]); return j+1; }else if( c=='n' && strncmp(pParse->zJson+i,"null",4)==0 && !isalnum(pParse->zJson[i+5]) ){ jsonParseAddNode(pParse, JSON_NULL, 0, 0); return i+4; }else if( c=='t' && strncmp(pParse->zJson+i,"true",4)==0 && !isalnum(pParse->zJson[i+5]) ){ jsonParseAddNode(pParse, JSON_TRUE, 0, 0); return i+4; }else if( c=='f' && strncmp(pParse->zJson+i,"false",5)==0 && !isalnum(pParse->zJson[i+6]) ){ jsonParseAddNode(pParse, JSON_FALSE, 0, 0); return i+5; }else if( c=='-' || (c>='0' && c<='9') ){ /* Parse number */ u8 seenDP = 0; u8 seenE = 0; j = i+1; for(;; j++){ c = pParse->zJson[j]; if( c>='0' && c<='9' ) continue; if( c=='.' ){ if( pParse->zJson[j-1]=='-' ) return -1; if( seenDP ) return -1; seenDP = 1; continue; } if( c=='e' || c=='E' ){ if( pParse->zJson[j-1]<'0' ) return -1; if( seenE ) return -1; seenDP = seenE = 1; c = pParse->zJson[j+1]; if( c=='+' || c=='-' ) j++; continue; } break; } if( pParse->zJson[j-1]<'0' ) return -1; jsonParseAddNode(pParse, seenDP ? JSON_REAL : JSON_INT, j - i, &pParse->zJson[i]); return j; }else if( c=='}' ){ return -2; /* End of {...} */ }else if( c==']' ){ return -3; /* End of [...] */ }else{ return -1; /* Syntax error */ } } /* ** Parse a complete JSON string. Return 0 on success or non-zero if there ** are any errors. If an error occurs, free all memory associated with ** pParse. ** ** pParse is uninitialized when this routine is called. */ static int jsonParse(JsonParse *pParse, const char *zJson){ int i; if( zJson==0 ) return 1; memset(pParse, 0, sizeof(*pParse)); pParse->zJson = zJson; i = jsonParseValue(pParse, 0); if( i>0 ){ while( isspace(zJson[i]) ) i++; if( zJson[i] ) i = -1; } if( i<0 ){ sqlite3_free(pParse->aNode); pParse->aNode = 0; pParse->nNode = 0; pParse->nAlloc = 0; return 1; } return 0; } /* ** The json_debug(JSON) function returns a string which describes ** a parse of the JSON provided. Or it returns NULL if JSON is not ** well-formed. */ static void jsonDebugFunc( sqlite3_context *context, int argc, sqlite3_value **argv ){ Json s; /* Output string - not real JSON */ JsonParse x; /* The parse */ u32 i; char zBuf[50]; static const char *azType[] = { "NULL", "TRUE", "FALSE", "INT", "REAL", "STRING", "ARRAY", "OBJECT" }; assert( argc==1 ); if( jsonParse(&x, (const char*)sqlite3_value_text(argv[0])) ) return; jsonInit(&s, context); for(i=0; i<x.nNode; i++){ sqlite3_snprintf(sizeof(zBuf), zBuf, "node %u:\n", i); jsonAppend(&s, zBuf); sqlite3_snprintf(sizeof(zBuf), zBuf, " type: %s\n", azType[x.aNode[i].eType]); jsonAppend(&s, zBuf); if( x.aNode[i].eType>=JSON_INT ){ sqlite3_snprintf(sizeof(zBuf), zBuf, " n: %u\n", x.aNode[i].n); jsonAppend(&s, zBuf); } if( x.aNode[i].zContent!=0 ){ sqlite3_snprintf(sizeof(zBuf), zBuf, " ofst: %u\n", (u32)(x.aNode[i].zContent - x.zJson)); jsonAppend(&s, zBuf); jsonAppendRaw(&s, " text: ", 8); jsonAppendRaw(&s, x.aNode[i].zContent, x.aNode[i].n); jsonAppendRaw(&s, "\n", 1); } } sqlite3_free(x.aNode); jsonResult(&s); } #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_json_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ int rc = SQLITE_OK; int i; static const struct { const char *zName; int nArg; void (*xFunc)(sqlite3_context*,int,sqlite3_value**); } aFunc[] = { { "json_array", -1, jsonArrayFunc }, { "jsonb_array", -1, jsonbArrayFunc }, { "json_object", -1, jsonObjectFunc }, { "json_debug", 1, jsonDebugFunc }, }; SQLITE_EXTENSION_INIT2(pApi); (void)pzErrMsg; /* Unused parameter */ for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){ rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg, SQLITE_UTF8 | SQLITE_DETERMINISTIC, 0, aFunc[i].xFunc, 0, 0); } return rc; } |