AryaWu/sqlite
0
1/*2** 2001 September 153**4** The author disclaims copyright to this source code. In place of5** a legal notice, here is a blessing:6**7** May you do good and not evil.8** May you find forgiveness for yourself and forgive others.9** May you share freely, never taking more than you give.10**11*************************************************************************12** An tokenizer for SQL13**14** This file contains C code that implements the sqlite3_complete() API.15** This code used to be part of the tokenizer.c source file. But by16** separating it out, the code will be automatically omitted from17** static links that do not use it.18*/19#include "sqliteInt.h"20#ifndef SQLITE_OMIT_COMPLETE21 22/*23** This is defined in tokenize.c. We just have to import the definition.24*/25#ifndef SQLITE_AMALGAMATION26#ifdef SQLITE_ASCII27#define IdChar(C) ((sqlite3CtypeMap[(unsigned char)C]&0x46)!=0)28#endif29#ifdef SQLITE_EBCDIC30extern const char sqlite3IsEbcdicIdChar[];31#define IdChar(C) (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))32#endif33#endif /* SQLITE_AMALGAMATION */34 35 36/*37** Token types used by the sqlite3_complete() routine. See the header38** comments on that procedure for additional information.39*/40#define tkSEMI 041#define tkWS 142#define tkOTHER 243#ifndef SQLITE_OMIT_TRIGGER44#define tkEXPLAIN 345#define tkCREATE 446#define tkTEMP 547#define tkTRIGGER 648#define tkEND 749#endif50 51/*52** Return TRUE if the given SQL string ends in a semicolon.53**54** Special handling is require for CREATE TRIGGER statements.55** Whenever the CREATE TRIGGER keywords are seen, the statement56** must end with ";END;".57**58** This implementation uses a state machine with 8 states:59**60** (0) INVALID We have not yet seen a non-whitespace character.61**62** (1) START At the beginning or end of an SQL statement. This routine63** returns 1 if it ends in the START state and 0 if it ends64** in any other state.65**66** (2) NORMAL We are in the middle of statement which ends with a single67** semicolon.68**69** (3) EXPLAIN The keyword EXPLAIN has been seen at the beginning of 70** a statement.71**72** (4) CREATE The keyword CREATE has been seen at the beginning of a73** statement, possibly preceded by EXPLAIN and/or followed by74** TEMP or TEMPORARY75**76** (5) TRIGGER We are in the middle of a trigger definition that must be77** ended by a semicolon, the keyword END, and another semicolon.78**79** (6) SEMI We've seen the first semicolon in the ";END;" that occurs at80** the end of a trigger definition.81**82** (7) END We've seen the ";END" of the ";END;" that occurs at the end83** of a trigger definition.84**85** Transitions between states above are determined by tokens extracted86** from the input. The following tokens are significant:87**88** (0) tkSEMI A semicolon.89** (1) tkWS Whitespace.90** (2) tkOTHER Any other SQL token.91** (3) tkEXPLAIN The "explain" keyword.92** (4) tkCREATE The "create" keyword.93** (5) tkTEMP The "temp" or "temporary" keyword.94** (6) tkTRIGGER The "trigger" keyword.95** (7) tkEND The "end" keyword.96**97** Whitespace never causes a state transition and is always ignored.98** This means that a SQL string of all whitespace is invalid.99**100** If we compile with SQLITE_OMIT_TRIGGER, all of the computation needed101** to recognize the end of a trigger can be omitted. All we have to do102** is look for a semicolon that is not part of an string or comment.103*/104int sqlite3_complete(const char *zSql){105 u8 state = 0; /* Current state, using numbers defined in header comment */106 u8 token; /* Value of the next token */107 108#ifndef SQLITE_OMIT_TRIGGER109 /* A complex statement machine used to detect the end of a CREATE TRIGGER110 ** statement. This is the normal case.111 */112 static const u8 trans[8][8] = {113 /* Token: */114 /* State: ** SEMI WS OTHER EXPLAIN CREATE TEMP TRIGGER END */115 /* 0 INVALID: */ { 1, 0, 2, 3, 4, 2, 2, 2, },116 /* 1 START: */ { 1, 1, 2, 3, 4, 2, 2, 2, },117 /* 2 NORMAL: */ { 1, 2, 2, 2, 2, 2, 2, 2, },118 /* 3 EXPLAIN: */ { 1, 3, 3, 2, 4, 2, 2, 2, },119 /* 4 CREATE: */ { 1, 4, 2, 2, 2, 4, 5, 2, },120 /* 5 TRIGGER: */ { 6, 5, 5, 5, 5, 5, 5, 5, },121 /* 6 SEMI: */ { 6, 6, 5, 5, 5, 5, 5, 7, },122 /* 7 END: */ { 1, 7, 5, 5, 5, 5, 5, 5, },123 };124#else125 /* If triggers are not supported by this compile then the statement machine126 ** used to detect the end of a statement is much simpler127 */128 static const u8 trans[3][3] = {129 /* Token: */130 /* State: ** SEMI WS OTHER */131 /* 0 INVALID: */ { 1, 0, 2, },132 /* 1 START: */ { 1, 1, 2, },133 /* 2 NORMAL: */ { 1, 2, 2, },134 };135#endif /* SQLITE_OMIT_TRIGGER */136 137#ifdef SQLITE_ENABLE_API_ARMOR138 if( zSql==0 ){139 (void)SQLITE_MISUSE_BKPT;140 return 0;141 }142#endif143 144 while( *zSql ){145 switch( *zSql ){146 case ';': { /* A semicolon */147 token = tkSEMI;148 break;149 }150 case ' ':151 case '\r':152 case '\t':153 case '\n':154 case '\f': { /* White space is ignored */155 token = tkWS;156 break;157 }158 case '/': { /* C-style comments */159 if( zSql[1]!='*' ){160 token = tkOTHER;161 break;162 }163 zSql += 2;164 while( zSql[0] && (zSql[0]!='*' || zSql[1]!='/') ){ zSql++; }165 if( zSql[0]==0 ) return 0;166 zSql++;167 token = tkWS;168 break;169 }170 case '-': { /* SQL-style comments from "--" to end of line */171 if( zSql[1]!='-' ){172 token = tkOTHER;173 break;174 }175 while( *zSql && *zSql!='\n' ){ zSql++; }176 if( *zSql==0 ) return state==1;177 token = tkWS;178 break;179 }180 case '[': { /* Microsoft-style identifiers in [...] */181 zSql++;182 while( *zSql && *zSql!=']' ){ zSql++; }183 if( *zSql==0 ) return 0;184 token = tkOTHER;185 break;186 }187 case '`': /* Grave-accent quoted symbols used by MySQL */188 case '"': /* single- and double-quoted strings */189 case '\'': {190 int c = *zSql;191 zSql++;192 while( *zSql && *zSql!=c ){ zSql++; }193 if( *zSql==0 ) return 0;194 token = tkOTHER;195 break;196 }197 default: {198#ifdef SQLITE_EBCDIC199 unsigned char c;200#endif201 if( IdChar((u8)*zSql) ){202 /* Keywords and unquoted identifiers */203 int nId;204 for(nId=1; IdChar(zSql[nId]); nId++){}205#ifdef SQLITE_OMIT_TRIGGER206 token = tkOTHER;207#else208 switch( *zSql ){209 case 'c': case 'C': {210 if( nId==6 && sqlite3StrNICmp(zSql, "create", 6)==0 ){211 token = tkCREATE;212 }else{213 token = tkOTHER;214 }215 break;216 }217 case 't': case 'T': {218 if( nId==7 && sqlite3StrNICmp(zSql, "trigger", 7)==0 ){219 token = tkTRIGGER;220 }else if( nId==4 && sqlite3StrNICmp(zSql, "temp", 4)==0 ){221 token = tkTEMP;222 }else if( nId==9 && sqlite3StrNICmp(zSql, "temporary", 9)==0 ){223 token = tkTEMP;224 }else{225 token = tkOTHER;226 }227 break;228 }229 case 'e': case 'E': {230 if( nId==3 && sqlite3StrNICmp(zSql, "end", 3)==0 ){231 token = tkEND;232 }else233#ifndef SQLITE_OMIT_EXPLAIN234 if( nId==7 && sqlite3StrNICmp(zSql, "explain", 7)==0 ){235 token = tkEXPLAIN;236 }else237#endif238 {239 token = tkOTHER;240 }241 break;242 }243 default: {244 token = tkOTHER;245 break;246 }247 }248#endif /* SQLITE_OMIT_TRIGGER */249 zSql += nId-1;250 }else{251 /* Operators and special symbols */252 token = tkOTHER;253 }254 break;255 }256 }257 state = trans[state][token];258 zSql++;259 }260 return state==1;261}262 263#ifndef SQLITE_OMIT_UTF16264/*265** This routine is the same as the sqlite3_complete() routine described266** above, except that the parameter is required to be UTF-16 encoded, not267** UTF-8.268*/269int sqlite3_complete16(const void *zSql){270 sqlite3_value *pVal;271 char const *zSql8;272 int rc;273 274#ifndef SQLITE_OMIT_AUTOINIT275 rc = sqlite3_initialize();276 if( rc ) return rc;277#endif278 pVal = sqlite3ValueNew(0);279 sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC);280 zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8);281 if( zSql8 ){282 rc = sqlite3_complete(zSql8);283 }else{284 rc = SQLITE_NOMEM_BKPT;285 }286 sqlite3ValueFree(pVal);287 return rc & 0xff;288}289#endif /* SQLITE_OMIT_UTF16 */290#endif /* SQLITE_OMIT_COMPLETE */291