From: drh Date: Tue, 11 Jul 2017 00:09:44 +0000 (+0000) Subject: Incomplete implementation of the COMPLETION table-valued function. So far it X-Git-Tag: version-3.20.0~83 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3265b5649ec87ca82026c7cd177434993a00c482;p=thirdparty%2Fsqlite.git Incomplete implementation of the COMPLETION table-valued function. So far it only works for SQL keywords. FossilOrigin-Name: caefbc723b5f67afc5ef10b92b20400cbb76cb03e7e75e18d2726cc552083e09 --- diff --git a/ext/misc/completion.c b/ext/misc/completion.c new file mode 100644 index 0000000000..f4cd1b91b7 --- /dev/null +++ b/ext/misc/completion.c @@ -0,0 +1,402 @@ +/* +** 2017-07-10 +** +** 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 implements an eponymous virtual table that returns suggested +** completions for a partial SQL input. +** +*/ +#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_COMPLETIONVTAB) +#if !defined(SQLITEINT_H) +#include "sqlite3ext.h" +#endif +SQLITE_EXTENSION_INIT1 +#include +#include +#include + +#ifndef SQLITE_OMIT_VIRTUALTABLE + +/* completion_vtab is a subclass of sqlite3_vtab which will +** serve as the underlying representation of a completion virtual table +*/ +typedef struct completion_vtab completion_vtab; +struct completion_vtab { + sqlite3_vtab base; /* Base class - must be first */ + sqlite3 *db; /* Database connection for this completion vtab */ +}; + +/* completion_cursor is a subclass of sqlite3_vtab_cursor which will +** serve as the underlying representation of a cursor that scans +** over rows of the result +*/ +typedef struct completion_cursor completion_cursor; +struct completion_cursor { + sqlite3_vtab_cursor base; /* Base class - must be first */ + sqlite3 *db; /* Database connection for this cursor */ + int nPrefix, nLine; /* Number of bytes in zPrefix and zLine */ + char *zPrefix; /* The prefix for the word we want to complete */ + char *zLine; /* The whole that we want to complete */ + const char *zCurrentRow; /* Current output row */ + sqlite3_stmt *pStmt; /* Current statement */ + sqlite3_int64 iRowid; /* The rowid */ + int ePhase; /* Current phase */ + int j; /* inter-phase counter */ +}; + +/* Values for ePhase: +*/ +#define COMPLETION_FIRST_PHASE 0 +#define COMPLETION_KEYWORDS 1 +#define COMPLETION_PRAGMAS 2 +#define COMPLETION_FUNCTIONS 3 +#define COMPLETION_COLLATIONS 4 +#define COMPLETION_INDEXES 5 +#define COMPLETION_TRIGGERS 6 +#define COMPLETION_DATABASES 7 +#define COMPLETION_TABLES 8 +#define COMPLETION_MODULES 9 +#define COMPLETION_LAST_PHASE 10 + +/* +** The completionConnect() method is invoked to create a new +** completion_vtab that describes the completion virtual table. +** +** Think of this routine as the constructor for completion_vtab objects. +** +** All this routine needs to do is: +** +** (1) Allocate the completion_vtab object and initialize all fields. +** +** (2) Tell SQLite (via the sqlite3_declare_vtab() interface) what the +** result set of queries against completion will look like. +*/ +static int completionConnect( + sqlite3 *db, + void *pAux, + int argc, const char *const*argv, + sqlite3_vtab **ppVtab, + char **pzErr +){ + completion_vtab *pNew; + int rc; + +/* Column numbers */ +#define COMPLETION_COLUMN_CANDIDATE 0 /* Suggested completion of the input */ +#define COMPLETION_COLUMN_PREFIX 1 /* Prefix of the word to be completed */ +#define COMPLETION_COLUMN_WHOLELINE 2 /* Entire line seen so far */ + + rc = sqlite3_declare_vtab(db, + "CREATE TABLE x(" + " candidate TEXT," + " prefix TEXT HIDDEN," + " wholeline TEXT HIDDEN" + ")"); + if( rc==SQLITE_OK ){ + pNew = sqlite3_malloc( sizeof(*pNew) ); + *ppVtab = (sqlite3_vtab*)pNew; + if( pNew==0 ) return SQLITE_NOMEM; + memset(pNew, 0, sizeof(*pNew)); + pNew->db = db; + } + return rc; +} + +/* +** This method is the destructor for completion_cursor objects. +*/ +static int completionDisconnect(sqlite3_vtab *pVtab){ + sqlite3_free(pVtab); + return SQLITE_OK; +} + +/* +** Constructor for a new completion_cursor object. +*/ +static int completionOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){ + completion_cursor *pCur; + pCur = sqlite3_malloc( sizeof(*pCur) ); + if( pCur==0 ) return SQLITE_NOMEM; + memset(pCur, 0, sizeof(*pCur)); + pCur->db = ((completion_vtab*)p)->db; + *ppCursor = &pCur->base; + return SQLITE_OK; +} + +/* +** Reset the completion_cursor. +*/ +static void completionCursorReset(completion_cursor *pCur){ + sqlite3_free(pCur->zPrefix); pCur->zPrefix = 0; pCur->nPrefix = 0; + sqlite3_free(pCur->zLine); pCur->zLine = 0; pCur->nLine = 0; + sqlite3_finalize(pCur->pStmt); pCur->pStmt = 0; +} + +/* +** Destructor for a completion_cursor. +*/ +static int completionClose(sqlite3_vtab_cursor *cur){ + completionCursorReset((completion_cursor*)cur); + sqlite3_free(cur); + return SQLITE_OK; +} + +/* +** All SQL keywords understood by SQLite +*/ +static const char *completionKwrds[] = { + "ABORT", "ACTION", "ADD", "AFTER", "ALL", "ALTER", "ANALYZE", "AND", "AS", + "ASC", "ATTACH", "AUTOINCREMENT", "BEFORE", "BEGIN", "BETWEEN", "BY", + "CASCADE", "CASE", "CAST", "CHECK", "COLLATE", "COLUMN", "COMMIT", + "CONFLICT", "CONSTRAINT", "CREATE", "CROSS", "CURRENT_DATE", + "CURRENT_TIME", "CURRENT_TIMESTAMP", "DATABASE", "DEFAULT", "DEFERRABLE", + "DEFERRED", "DELETE", "DESC", "DETACH", "DISTINCT", "DROP", "EACH", + "ELSE", "END", "ESCAPE", "EXCEPT", "EXCLUSIVE", "EXISTS", "EXPLAIN", + "FAIL", "FOR", "FOREIGN", "FROM", "FULL", "GLOB", "GROUP", "HAVING", "IF", + "IGNORE", "IMMEDIATE", "IN", "INDEX", "INDEXED", "INITIALLY", "INNER", + "INSERT", "INSTEAD", "INTERSECT", "INTO", "IS", "ISNULL", "JOIN", "KEY", + "LEFT", "LIKE", "LIMIT", "MATCH", "NATURAL", "NO", "NOT", "NOTNULL", + "NULL", "OF", "OFFSET", "ON", "OR", "ORDER", "OUTER", "PLAN", "PRAGMA", + "PRIMARY", "QUERY", "RAISE", "RECURSIVE", "REFERENCES", "REGEXP", + "REINDEX", "RELEASE", "RENAME", "REPLACE", "RESTRICT", "RIGHT", + "ROLLBACK", "ROW", "SAVEPOINT", "SELECT", "SET", "TABLE", "TEMP", + "TEMPORARY", "THEN", "TO", "TRANSACTION", "TRIGGER", "UNION", "UNIQUE", + "UPDATE", "USING", "VACUUM", "VALUES", "VIEW", "VIRTUAL", "WHEN", "WHERE", + "WITH", "WITHOUT", +}; + +/* +** Advance a completion_cursor to its next row of output. +*/ +static int completionNext(sqlite3_vtab_cursor *cur){ + completion_cursor *pCur = (completion_cursor*)cur; + pCur->iRowid++; + if( pCur->ePhase==COMPLETION_FIRST_PHASE ){ + pCur->ePhase = COMPLETION_KEYWORDS; + pCur->j = -1; + } + if( pCur->ePhase==COMPLETION_KEYWORDS ){ + while(1){ + const char *z; + pCur->j++; + if( pCur->j >= sizeof(completionKwrds)/sizeof(completionKwrds[0]) ){ + pCur->ePhase = COMPLETION_LAST_PHASE; + break; + } + z = completionKwrds[pCur->j]; + if( pCur->nPrefix==0 + || sqlite3_strnicmp(pCur->zPrefix, z, pCur->nPrefix)==0 + ){ + pCur->zCurrentRow = z; + break; + } + } + } + return SQLITE_OK; +} + +/* +** Return values of columns for the row at which the completion_cursor +** is currently pointing. +*/ +static int completionColumn( + sqlite3_vtab_cursor *cur, /* The cursor */ + sqlite3_context *ctx, /* First argument to sqlite3_result_...() */ + int i /* Which column to return */ +){ + completion_cursor *pCur = (completion_cursor*)cur; + switch( i ){ + case COMPLETION_COLUMN_CANDIDATE: { + sqlite3_result_text(ctx, pCur->zCurrentRow, -1, SQLITE_TRANSIENT); + break; + } + case COMPLETION_COLUMN_PREFIX: { + sqlite3_result_text(ctx, pCur->zPrefix, -1, SQLITE_TRANSIENT); + break; + } + case COMPLETION_COLUMN_WHOLELINE: { + sqlite3_result_text(ctx, pCur->zLine, -1, SQLITE_TRANSIENT); + break; + } + } + return SQLITE_OK; +} + +/* +** Return the rowid for the current row. In this implementation, the +** rowid is the same as the output value. +*/ +static int completionRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){ + completion_cursor *pCur = (completion_cursor*)cur; + *pRowid = pCur->iRowid; + return SQLITE_OK; +} + +/* +** Return TRUE if the cursor has been moved off of the last +** row of output. +*/ +static int completionEof(sqlite3_vtab_cursor *cur){ + completion_cursor *pCur = (completion_cursor*)cur; + return pCur->ePhase >= COMPLETION_LAST_PHASE; +} + +/* +** This method is called to "rewind" the completion_cursor object back +** to the first row of output. This method is always called at least +** once prior to any call to completionColumn() or completionRowid() or +** completionEof(). +*/ +static int completionFilter( + sqlite3_vtab_cursor *pVtabCursor, + int idxNum, const char *idxStr, + int argc, sqlite3_value **argv +){ + completion_cursor *pCur = (completion_cursor *)pVtabCursor; + int iArg = 0; + completionCursorReset(pCur); + if( idxNum & 1 ){ + pCur->nPrefix = sqlite3_value_bytes(argv[iArg]); + if( pCur->nPrefix>0 ){ + pCur->zPrefix = sqlite3_mprintf("%s", sqlite3_value_text(argv[iArg])); + if( pCur->zPrefix==0 ) return SQLITE_NOMEM; + } + iArg++; + } + if( idxNum & 2 ){ + pCur->nLine = sqlite3_value_bytes(argv[iArg]); + if( pCur->nLine>0 ){ + pCur->zLine = sqlite3_mprintf("%s", sqlite3_value_text(argv[iArg])); + if( pCur->zLine==0 ) return SQLITE_NOMEM; + } + iArg++; + } + if( pCur->zLine!=0 && pCur->zPrefix==0 ){ + int i = pCur->nLine; + while( i>0 && (isalnum(pCur->zLine[i-1]) || pCur->zLine[i-1]=='_') ){ + i--; + } + pCur->nPrefix = pCur->nLine - i; + if( pCur->nPrefix>0 ){ + pCur->zPrefix = sqlite3_mprintf("%.*s", pCur->nPrefix, pCur->zLine + i); + if( pCur->zPrefix==0 ) return SQLITE_NOMEM; + } + } + pCur->iRowid = 0; + pCur->ePhase = COMPLETION_FIRST_PHASE; + return completionNext(pVtabCursor); +} + +/* +** SQLite will invoke this method one or more times while planning a query +** that uses the completion virtual table. This routine needs to create +** a query plan for each invocation and compute an estimated cost for that +** plan. +** +** There are two hidden parameters that act as arguments to the table-valued +** function: "prefix" and "wholeline". Bit 0 of idxNum is set if "prefix" +** is available and bit 1 is set if "wholeline" is available. +*/ +static int completionBestIndex( + sqlite3_vtab *tab, + sqlite3_index_info *pIdxInfo +){ + int i; /* Loop over constraints */ + int idxNum = 0; /* The query plan bitmask */ + int prefixIdx = -1; /* Index of the start= constraint, or -1 if none */ + int wholelineIdx = -1; /* Index of the stop= constraint, or -1 if none */ + int nArg = 0; /* Number of arguments that completeFilter() expects */ + const struct sqlite3_index_constraint *pConstraint; + + pConstraint = pIdxInfo->aConstraint; + for(i=0; inConstraint; i++, pConstraint++){ + if( pConstraint->usable==0 ) continue; + if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue; + switch( pConstraint->iColumn ){ + case COMPLETION_COLUMN_PREFIX: + prefixIdx = i; + idxNum |= 1; + break; + case COMPLETION_COLUMN_WHOLELINE: + wholelineIdx = i; + idxNum |= 2; + break; + } + } + if( prefixIdx>=0 ){ + pIdxInfo->aConstraintUsage[prefixIdx].argvIndex = ++nArg; + pIdxInfo->aConstraintUsage[prefixIdx].omit = 1; + } + if( wholelineIdx>=0 ){ + pIdxInfo->aConstraintUsage[wholelineIdx].argvIndex = ++nArg; + pIdxInfo->aConstraintUsage[wholelineIdx].omit = 1; + } + pIdxInfo->idxNum = idxNum; + pIdxInfo->estimatedCost = (double)5000 - 1000*nArg; + pIdxInfo->estimatedRows = 500 - 100*nArg; + return SQLITE_OK; +} + +/* +** This following structure defines all the methods for the +** completion virtual table. +*/ +static sqlite3_module completionModule = { + 0, /* iVersion */ + 0, /* xCreate */ + completionConnect, /* xConnect */ + completionBestIndex, /* xBestIndex */ + completionDisconnect, /* xDisconnect */ + 0, /* xDestroy */ + completionOpen, /* xOpen - open a cursor */ + completionClose, /* xClose - close a cursor */ + completionFilter, /* xFilter - configure scan constraints */ + completionNext, /* xNext - advance a cursor */ + completionEof, /* xEof - check for end of scan */ + completionColumn, /* xColumn - read data */ + completionRowid, /* xRowid - read data */ + 0, /* xUpdate */ + 0, /* xBegin */ + 0, /* xSync */ + 0, /* xCommit */ + 0, /* xRollback */ + 0, /* xFindMethod */ + 0, /* xRename */ +}; + +#endif /* SQLITE_OMIT_VIRTUALTABLE */ + +int sqlite3CompletionVtabInit(sqlite3 *db){ + int rc = SQLITE_OK; +#ifndef SQLITE_OMIT_VIRTUALTABLE + rc = sqlite3_create_module(db, "completion", &completionModule, 0); +#endif + return rc; +} + +#ifndef SQLITE_CORE +#ifdef _WIN32 +__declspec(dllexport) +#endif +int sqlite3_completion_init( + sqlite3 *db, + char **pzErrMsg, + const sqlite3_api_routines *pApi +){ + int rc = SQLITE_OK; + SQLITE_EXTENSION_INIT2(pApi); +#ifndef SQLITE_OMIT_VIRTUALTABLE + rc = sqlite3CompletionVtabInit(db); +#endif + return rc; +} +#endif /* SQLITE_CORE */ +#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_COMPLETIONVTAB) */ diff --git a/manifest b/manifest index b93b909920..1325b5b8ae 100644 --- a/manifest +++ b/manifest @@ -1,5 +1,5 @@ -C Fix\sharmless\scompiler\swarnings\sin\slsmtest. -D 2017-07-10T21:32:11.229 +C Incomplete\simplementation\sof\sthe\sCOMPLETION\stable-valued\sfunction.\s\sSo\sfar\sit\nonly\sworks\sfor\sSQL\skeywords. +D 2017-07-11T00:09:44.330 F Makefile.in 081e48dfe7f995d57ce1a88ddf4d2917b4349158648a6cd45b42beae30de3a12 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434 F Makefile.msc 20850e3e8d4d4791e0531955852d768eb06f24138214870d543abb1a47346fba @@ -256,6 +256,7 @@ F ext/misc/amatch.c 6db4607cb17c54b853a2d7c7c36046d004853f65b9b733e6f019d543d5df F ext/misc/anycollseq.c 5ffdfde9829eeac52219136ad6aa7cd9a4edb3b15f4f2532de52f4a22525eddb F ext/misc/carray.c 40c27641010a4dc67e3690bdb7c9d36ca58b3c2d F ext/misc/closure.c 0d2a038df8fbae7f19de42e7c7d71f2e4dc88704 +F ext/misc/completion.c 1b58092f73e9c6025d055b5e01f22273f378de2bf3a1db0d6b5dfe79dddce5f7 F ext/misc/compress.c 122faa92d25033d6c3f07c39231de074ab3d2e83 F ext/misc/csv.c d91c0388445b08f6e373dd0e8fc024d4551b1fcaf64e876a1c3f4fac8a63adc2 F ext/misc/dbdump.c 3509fa6b8932d04e932d6b6b827b6a82ca362781b8e8f3c77336f416793e215e @@ -1628,7 +1629,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0 -P 9a8f045d62f5c6593a5a2842e817b49fa9d00c74e329a15a326f74e583c1f767 -R 4826077b144be43a7ed321a8e8c27dc4 -U mistachkin -Z 5556057292ec12960fe9453577b50312 +P bd8a1fb9b33418717c786a7275f636cd4d5facd66de9a416f948b61c6490c743 +R c31437c94c579e099f5c663f8abfebe7 +U drh +Z 2bab86907269899ac4b24013169de866 diff --git a/manifest.uuid b/manifest.uuid index a462892ce0..ec03a9d963 100644 --- a/manifest.uuid +++ b/manifest.uuid @@ -1 +1 @@ -bd8a1fb9b33418717c786a7275f636cd4d5facd66de9a416f948b61c6490c743 \ No newline at end of file +caefbc723b5f67afc5ef10b92b20400cbb76cb03e7e75e18d2726cc552083e09 \ No newline at end of file