/* ** 2012-11-13 ** ** 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. ** ****************************************************************************** ** ** The code in this file implements a compact but reasonably ** efficient regular-expression matcher for posix extended regular ** expressions against UTF8 text. ** ** This file is an SQLite extension. It registers a single function ** named "regexp(A,B)" where A is the regular expression and B is the ** string to be matched. By registering this function, SQLite will also ** then implement the "B regexp A" operator. Note that with the function ** the regular expression comes first, but with the operator it comes ** second. ** ** The following regular expression syntax is supported: ** ** X* zero or more occurrences of X ** X+ one or more occurrences of X ** X? zero or one occurrences of X ** X{p,q} between p and q occurrences of X ** (X) match X ** X|Y X or Y ** ^X X occurring at the beginning of the string ** X$ X occurring at the end of the string ** . Match any single character ** \c Character c where c is one of \{}()[]|*+?. ** \c C-language escapes for c in afnrtv. ex: \t or \n ** \uXXXX Where XXXX is exactly 4 hex digits, unicode value XXXX ** \xXX Where XX is exactly 2 hex digits, unicode value XX ** [abc] Any single character from the set abc ** [^abc] Any single character not in the set abc ** [a-z] Any single character in the range a-z ** [^a-z] Any single character not in the range a-z ** \b Word boundary ** \w Word character. [A-Za-z0-9_] ** \W Non-word character ** \d Digit ** \D Non-digit ** \s Whitespace character ** \S Non-whitespace character ** ** A nondeterministic finite automaton (NFA) is used for matching, so the ** performance is bounded by O(N*M) where N is the size of the regular ** expression and M is the size of the input string. The matcher never ** exhibits exponential behavior. Note that the X{p,q} operator expands ** to p copies of X following by q-p copies of X? and that the size of the ** regular expression in the O(N*M) performance bound is computed after ** this expansion. */ #include <string.h> #include <stdlib.h> #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 /* ** The following #defines change the names of some functions implemented in ** this file to prevent name collisions with C-library functions of the ** same name. */ #define re_match sqlite3re_match #define re_compile sqlite3re_compile #define re_free sqlite3re_free /* The end-of-input character */ #define RE_EOF 0 /* End of input */ #define RE_START 0xfffffff /* Start of input - larger than an UTF-8 */ /* The NFA is implemented as sequence of opcodes taken from the following ** set. Each opcode has a single integer argument. */ #define RE_OP_MATCH 1 /* Match the one character in the argument */ #define RE_OP_ANY 2 /* Match any one character. (Implements ".") */ #define RE_OP_ANYSTAR 3 /* Special optimized version of .* */ #define RE_OP_FORK 4 /* Continue to both next and opcode at iArg */ #define RE_OP_GOTO 5 /* Jump to opcode at iArg */ #define RE_OP_ACCEPT 6 /* Halt and indicate a successful match */ #define RE_OP_CC_INC 7 /* Beginning of a [...] character class */ #define RE_OP_CC_EXC 8 /* Beginning of a [^...] character class */ #define RE_OP_CC_VALUE 9 /* Single value in a character class */ #define RE_OP_CC_RANGE 10 /* Range of values in a character class */ #define RE_OP_WORD 11 /* Perl word character [A-Za-z0-9_] */ #define RE_OP_NOTWORD 12 /* Not a perl word character */ #define RE_OP_DIGIT 13 /* digit: [0-9] */ #define RE_OP_NOTDIGIT 14 /* Not a digit */ #define RE_OP_SPACE 15 /* space: [ \t\n\r\v\f] */ #define RE_OP_NOTSPACE 16 /* Not a digit */ #define RE_OP_BOUNDARY 17 /* Boundary between word and non-word */ #define RE_OP_ATSTART 18 /* Currently at the start of the string */ #if defined(SQLITE_DEBUG) /* Opcode names used for symbolic debugging */ static const char *ReOpName[] = { "EOF", "MATCH", "ANY", "ANYSTAR", "FORK", "GOTO", "ACCEPT", "CC_INC", "CC_EXC", "CC_VALUE", "CC_RANGE", "WORD", "NOTWORD", "DIGIT", "NOTDIGIT", "SPACE", "NOTSPACE", "BOUNDARY", "ATSTART", }; #endif /* SQLITE_DEBUG */ /* Each opcode is a "state" in the NFA */ typedef unsigned short ReStateNumber; /* Because this is an NFA and not a DFA, multiple states can be active at ** once. An instance of the following object records all active states in ** the NFA. The implementation is optimized for the common case where the ** number of actives states is small. */ typedef struct ReStateSet { unsigned nState; /* Number of current states */ ReStateNumber *aState; /* Current states */ } ReStateSet; /* An input string read one character at a time. */ typedef struct ReInput ReInput; struct ReInput { const unsigned char *z; /* All text */ int i; /* Next byte to read */ int mx; /* EOF when i>=mx */ }; /* A compiled NFA (or an NFA that is in the process of being compiled) is ** an instance of the following object. */ typedef struct ReCompiled ReCompiled; struct ReCompiled { ReInput sIn; /* Regular expression text */ const char *zErr; /* Error message to return */ char *aOp; /* Operators for the virtual machine */ int *aArg; /* Arguments to each operator */ unsigned (*xNextChar)(ReInput*); /* Next character function */ unsigned char zInit[12]; /* Initial text to match */ int nInit; /* Number of bytes in zInit */ unsigned nState; /* Number of entries in aOp[] and aArg[] */ unsigned nAlloc; /* Slots allocated for aOp[] and aArg[] */ }; /* Add a state to the given state set if it is not already there */ static void re_add_state(ReStateSet *pSet, int newState){ unsigned i; for(i=0; i<pSet->nState; i++) if( pSet->aState[i]==newState ) return; pSet->aState[pSet->nState++] = (ReStateNumber)newState; } /* Extract the next unicode character from *pzIn and return it. Advance ** *pzIn to the first byte past the end of the character returned. To ** be clear: this routine converts utf8 to unicode. This routine is ** optimized for the common case where the next character is a single byte. */ static unsigned re_next_char(ReInput *p){ unsigned c; if( p->i>=p->mx ) return 0; c = p->z[p->i++]; if( c>=0x80 ){ if( (c&0xe0)==0xc0 && p->i<p->mx && (p->z[p->i]&0xc0)==0x80 ){ c = (c&0x1f)<<6 | (p->z[p->i++]&0x3f); if( c<0x80 ) c = 0xfffd; }else if( (c&0xf0)==0xe0 && p->i+1<p->mx && (p->z[p->i]&0xc0)==0x80 && (p->z[p->i+1]&0xc0)==0x80 ){ c = (c&0x0f)<<12 | ((p->z[p->i]&0x3f)<<6) | (p->z[p->i+1]&0x3f); p->i += 2; if( c<=0x7ff || (c>=0xd800 && c<=0xdfff) ) c = 0xfffd; }else if( (c&0xf8)==0xf0 && p->i+2<p->mx && (p->z[p->i]&0xc0)==0x80 && (p->z[p->i+1]&0xc0)==0x80 && (p->z[p->i+2]&0xc0)==0x80 ){ c = (c&0x07)<<18 | ((p->z[p->i]&0x3f)<<12) | ((p->z[p->i+1]&0x3f)<<6) | (p->z[p->i+2]&0x3f); p->i += 3; if( c<=0xffff || c>0x10ffff ) c = 0xfffd; }else{ c = 0xfffd; } } return c; } static unsigned re_next_char_nocase(ReInput *p){ unsigned c = re_next_char(p); if( c>='A' && c<='Z' ) c += 'a' - 'A'; return c; } /* Return true if c is a perl "word" character: [A-Za-z0-9_] */ static int re_word_char(int c){ return (c>='0' && c<='9') || (c>='a' && c<='z') || (c>='A' && c<='Z') || c=='_'; } /* Return true if c is a "digit" character: [0-9] */ static int re_digit_char(int c){ return (c>='0' && c<='9'); } /* Return true if c is a perl "space" character: [ \t\r\n\v\f] */ static int re_space_char(int c){ return c==' ' || c=='\t' || c=='\n' || c=='\r' || c=='\v' || c=='\f'; } /* Run a compiled regular expression on the zero-terminated input ** string zIn[]. Return true on a match and false if there is no match. */ static int re_match(ReCompiled *pRe, const unsigned char *zIn, int nIn){ ReStateSet aStateSet[2], *pThis, *pNext; ReStateNumber aSpace[100]; ReStateNumber *pToFree; unsigned int i = 0; unsigned int iSwap = 0; int c = RE_START; int cPrev = 0; int rc = 0; ReInput in; in.z = zIn; in.i = 0; in.mx = nIn>=0 ? nIn : (int)strlen((char const*)zIn); /* Look for the initial prefix match, if there is one. */ if( pRe->nInit ){ unsigned char x = pRe->zInit[0]; while( in.i+pRe->nInit<=in.mx && (zIn[in.i]!=x || strncmp((const char*)zIn+in.i, (const char*)pRe->zInit, pRe->nInit)!=0) ){ in.i++; } if( in.i+pRe->nInit>in.mx ) return 0; c = RE_START-1; } if( pRe->nState<=(sizeof(aSpace)/(sizeof(aSpace[0])*2)) ){ pToFree = 0; aStateSet[0].aState = aSpace; }else{ pToFree = sqlite3_malloc64( sizeof(ReStateNumber)*2*pRe->nState ); if( pToFree==0 ) return -1; aStateSet[0].aState = pToFree; } aStateSet[1].aState = &aStateSet[0].aState[pRe->nState]; pNext = &aStateSet[1]; pNext->nState = 0; re_add_state(pNext, 0); while( c!=RE_EOF && pNext->nState>0 ){ cPrev = c; c = pRe->xNextChar(&in); pThis = pNext; pNext = &aStateSet[iSwap]; iSwap = 1 - iSwap; pNext->nState = 0; for(i=0; i<pThis->nState; i++){ int x = pThis->aState[i]; switch( pRe->aOp[x] ){ case RE_OP_MATCH: { if( pRe->aArg[x]==c ) re_add_state(pNext, x+1); break; } case RE_OP_ATSTART: { if( cPrev==RE_START ) re_add_state(pThis, x+1); break; } case RE_OP_ANY: { if( c!=0 ) re_add_state(pNext, x+1); break; } case RE_OP_WORD: { if( re_word_char(c) ) re_add_state(pNext, x+1); break; } case RE_OP_NOTWORD: { if( !re_word_char(c) && c!=0 ) re_add_state(pNext, x+1); break; } case RE_OP_DIGIT: { if( re_digit_char(c) ) re_add_state(pNext, x+1); break; } case RE_OP_NOTDIGIT: { if( !re_digit_char(c) && c!=0 ) re_add_state(pNext, x+1); break; } case RE_OP_SPACE: { if( re_space_char(c) ) re_add_state(pNext, x+1); break; } case RE_OP_NOTSPACE: { if( !re_space_char(c) && c!=0 ) re_add_state(pNext, x+1); break; } case RE_OP_BOUNDARY: { if( re_word_char(c)!=re_word_char(cPrev) ) re_add_state(pThis, x+1); break; } case RE_OP_ANYSTAR: { re_add_state(pNext, x); re_add_state(pThis, x+1); break; } case RE_OP_FORK: { re_add_state(pThis, x+pRe->aArg[x]); re_add_state(pThis, x+1); break; } case RE_OP_GOTO: { re_add_state(pThis, x+pRe->aArg[x]); break; } case RE_OP_ACCEPT: { rc = 1; goto re_match_end; } case RE_OP_CC_EXC: { if( c==0 ) break; /* fall-through */ goto re_op_cc_inc; } case RE_OP_CC_INC: re_op_cc_inc: { int j = 1; int n = pRe->aArg[x]; int hit = 0; for(j=1; j>0 && j<n; j++){ if( pRe->aOp[x+j]==RE_OP_CC_VALUE ){ if( pRe->aArg[x+j]==c ){ hit = 1; j = -1; } }else{ if( pRe->aArg[x+j]<=c && pRe->aArg[x+j+1]>=c ){ hit = 1; j = -1; }else{ j++; } } } if( pRe->aOp[x]==RE_OP_CC_EXC ) hit = !hit; if( hit ) re_add_state(pNext, x+n); break; } } } } for(i=0; i<pNext->nState; i++){ int x = pNext->aState[i]; while( pRe->aOp[x]==RE_OP_GOTO ) x += pRe->aArg[x]; if( pRe->aOp[x]==RE_OP_ACCEPT ){ rc = 1; break; } } re_match_end: sqlite3_free(pToFree); return rc; } /* Resize the opcode and argument arrays for an RE under construction. */ static int re_resize(ReCompiled *p, int N){ char *aOp; int *aArg; aOp = sqlite3_realloc64(p->aOp, N*sizeof(p->aOp[0])); if( aOp==0 ) return 1; p->aOp = aOp; aArg = sqlite3_realloc64(p->aArg, N*sizeof(p->aArg[0])); if( aArg==0 ) return 1; p->aArg = aArg; p->nAlloc = N; return 0; } /* Insert a new opcode and argument into an RE under construction. The ** insertion point is just prior to existing opcode iBefore. */ static int re_insert(ReCompiled *p, int iBefore, int op, int arg){ int i; if( p->nAlloc<=p->nState && re_resize(p, p->nAlloc*2) ) return 0; for(i=p->nState; i>iBefore; i--){ p->aOp[i] = p->aOp[i-1]; p->aArg[i] = p->aArg[i-1]; } p->nState++; p->aOp[iBefore] = (char)op; p->aArg[iBefore] = arg; return iBefore; } /* Append a new opcode and argument to the end of the RE under construction. */ static int re_append(ReCompiled *p, int op, int arg){ return re_insert(p, p->nState, op, arg); } /* Make a copy of N opcodes starting at iStart onto the end of the RE ** under construction. */ static void re_copy(ReCompiled *p, int iStart, int N){ if( p->nState+N>=p->nAlloc && re_resize(p, p->nAlloc*2+N) ) return; memcpy(&p->aOp[p->nState], &p->aOp[iStart], N*sizeof(p->aOp[0])); memcpy(&p->aArg[p->nState], &p->aArg[iStart], N*sizeof(p->aArg[0])); p->nState += N; } /* Return true if c is a hexadecimal digit character: [0-9a-fA-F] ** If c is a hex digit, also set *pV = (*pV)*16 + valueof(c). If ** c is not a hex digit *pV is unchanged. */ static int re_hex(int c, int *pV){ if( c>='0' && c<='9' ){ c -= '0'; }else if( c>='a' && c<='f' ){ c -= 'a' - 10; }else if( c>='A' && c<='F' ){ c -= 'A' - 10; }else{ return 0; } *pV = (*pV)*16 + (c & 0xff); return 1; } /* A backslash character has been seen, read the next character and ** return its interpretation. */ static unsigned re_esc_char(ReCompiled *p){ static const char zEsc[] = "afnrtv\\()*.+?[$^{|}]"; static const char zTrans[] = "\a\f\n\r\t\v"; int i, v = 0; char c; if( p->sIn.i>=p->sIn.mx ) return 0; c = p->sIn.z[p->sIn.i]; if( c=='u' && p->sIn.i+4<p->sIn.mx ){ const unsigned char *zIn = p->sIn.z + p->sIn.i; if( re_hex(zIn[1],&v) && re_hex(zIn[2],&v) && re_hex(zIn[3],&v) && re_hex(zIn[4],&v) ){ p->sIn.i += 5; return v; } } if( c=='x' && p->sIn.i+2<p->sIn.mx ){ const unsigned char *zIn = p->sIn.z + p->sIn.i; if( re_hex(zIn[1],&v) && re_hex(zIn[2],&v) ){ p->sIn.i += 3; return v; } } for(i=0; zEsc[i] && zEsc[i]!=c; i++){} if( zEsc[i] ){ if( i<6 ) c = zTrans[i]; p->sIn.i++; }else{ p->zErr = "unknown \\ escape"; } return c; } /* Forward declaration */ static const char *re_subcompile_string(ReCompiled*); /* Peek at the next byte of input */ static unsigned char rePeek(ReCompiled *p){ return p->sIn.i<p->sIn.mx ? p->sIn.z[p->sIn.i] : 0; } /* Compile RE text into a sequence of opcodes. Continue up to the ** first unmatched ")" character, then return. If an error is found, ** return a pointer to the error message string. */ static const char *re_subcompile_re(ReCompiled *p){ const char *zErr; int iStart, iEnd, iGoto; iStart = p->nState; zErr = re_subcompile_string(p); if( zErr ) return zErr; while( rePeek(p)=='|' ){ iEnd = p->nState; re_insert(p, iStart, RE_OP_FORK, iEnd + 2 - iStart); iGoto = re_append(p, RE_OP_GOTO, 0); p->sIn.i++; zErr = re_subcompile_string(p); if( zErr ) return zErr; p->aArg[iGoto] = p->nState - iGoto; } return 0; } /* Compile an element of regular expression text (anything that can be ** an operand to the "|" operator). Return NULL on success or a pointer ** to the error message if there is a problem. */ static const char *re_subcompile_string(ReCompiled *p){ int iPrev = -1; int iStart; unsigned c; const char *zErr; while( (c = p->xNextChar(&p->sIn))!=0 ){ iStart = p->nState; switch( c ){ case '|': case ')': { p->sIn.i--; return 0; } case '(': { zErr = re_subcompile_re(p); if( zErr ) return zErr; if( rePeek(p)!=')' ) return "unmatched '('"; p->sIn.i++; break; } case '.': { if( rePeek(p)=='*' ){ re_append(p, RE_OP_ANYSTAR, 0); p->sIn.i++; }else{ re_append(p, RE_OP_ANY, 0); } break; } case '*': { if( iPrev<0 ) return "'*' without operand"; re_insert(p, iPrev, RE_OP_GOTO, p->nState - iPrev + 1); re_append(p, RE_OP_FORK, iPrev - p->nState + 1); break; } case '+': { if( iPrev<0 ) return "'+' without operand"; re_append(p, RE_OP_FORK, iPrev - p->nState); break; } case '?': { if( iPrev<0 ) return "'?' without operand"; re_insert(p, iPrev, RE_OP_FORK, p->nState - iPrev+1); break; } case '$': { re_append(p, RE_OP_MATCH, RE_EOF); break; } case '^': { re_append(p, RE_OP_ATSTART, 0); break; } case '{': { int m = 0, n = 0; int sz, j; if( iPrev<0 ) return "'{m,n}' without operand"; while( (c=rePeek(p))>='0' && c<='9' ){ m = m*10 + c - '0'; p->sIn.i++; } n = m; if( c==',' ){ p->sIn.i++; n = 0; while( (c=rePeek(p))>='0' && c<='9' ){ n = n*10 + c-'0'; p->sIn.i++; } } if( c!='}' ) return "unmatched '{'"; if( n>0 && n<m ) return "n less than m in '{m,n}'"; p->sIn.i++; sz = p->nState - iPrev; if( m==0 ){ if( n==0 ) return "both m and n are zero in '{m,n}'"; re_insert(p, iPrev, RE_OP_FORK, sz+1); iPrev++; n--; }else{ for(j=1; j<m; j++) re_copy(p, iPrev, sz); } for(j=m; j<n; j++){ re_append(p, RE_OP_FORK, sz+1); re_copy(p, iPrev, sz); } if( n==0 && m>0 ){ re_append(p, RE_OP_FORK, -sz); } break; } case '[': { unsigned int iFirst = p->nState; if( rePeek(p)=='^' ){ re_append(p, RE_OP_CC_EXC, 0); p->sIn.i++; }else{ re_append(p, RE_OP_CC_INC, 0); } while( (c = p->xNextChar(&p->sIn))!=0 ){ if( c=='[' && rePeek(p)==':' ){ return "POSIX character classes not supported"; } if( c=='\\' ) c = re_esc_char(p); if( rePeek(p)=='-' ){ re_append(p, RE_OP_CC_RANGE, c); p->sIn.i++; c = p->xNextChar(&p->sIn); if( c=='\\' ) c = re_esc_char(p); re_append(p, RE_OP_CC_RANGE, c); }else{ re_append(p, RE_OP_CC_VALUE, c); } if( rePeek(p)==']' ){ p->sIn.i++; break; } } if( c==0 ) return "unclosed '['"; if( p->nState>iFirst ) p->aArg[iFirst] = p->nState - iFirst; break; } case '\\': { int specialOp = 0; switch( rePeek(p) ){ case 'b': specialOp = RE_OP_BOUNDARY; break; case 'd': specialOp = RE_OP_DIGIT; break; case 'D': specialOp = RE_OP_NOTDIGIT; break; case 's': specialOp = RE_OP_SPACE; break; case 'S': specialOp = RE_OP_NOTSPACE; break; case 'w': specialOp = RE_OP_WORD; break; case 'W': specialOp = RE_OP_NOTWORD; break; } if( specialOp ){ p->sIn.i++; re_append(p, specialOp, 0); }else{ c = re_esc_char(p); re_append(p, RE_OP_MATCH, c); } break; } default: { re_append(p, RE_OP_MATCH, c); break; } } iPrev = iStart; } return 0; } /* Free and reclaim all the memory used by a previously compiled ** regular expression. Applications should invoke this routine once ** for every call to re_compile() to avoid memory leaks. */ static void re_free(ReCompiled *pRe){ if( pRe ){ sqlite3_free(pRe->aOp); sqlite3_free(pRe->aArg); sqlite3_free(pRe); } } /* ** Compile a textual regular expression in zIn[] into a compiled regular ** expression suitable for us by re_match() and return a pointer to the ** compiled regular expression in *ppRe. Return NULL on success or an ** error message if something goes wrong. */ static const char *re_compile(ReCompiled **ppRe, const char *zIn, int noCase){ ReCompiled *pRe; const char *zErr; int i, j; *ppRe = 0; pRe = sqlite3_malloc( sizeof(*pRe) ); if( pRe==0 ){ return "out of memory"; } memset(pRe, 0, sizeof(*pRe)); pRe->xNextChar = noCase ? re_next_char_nocase : re_next_char; if( re_resize(pRe, 30) ){ re_free(pRe); return "out of memory"; } if( zIn[0]=='^' ){ zIn++; }else{ re_append(pRe, RE_OP_ANYSTAR, 0); } pRe->sIn.z = (unsigned char*)zIn; pRe->sIn.i = 0; pRe->sIn.mx = (int)strlen(zIn); zErr = re_subcompile_re(pRe); if( zErr ){ re_free(pRe); return zErr; } if( pRe->sIn.i>=pRe->sIn.mx ){ re_append(pRe, RE_OP_ACCEPT, 0); *ppRe = pRe; }else{ re_free(pRe); return "unrecognized character"; } /* The following is a performance optimization. If the regex begins with ** ".*" (if the input regex lacks an initial "^") and afterwards there are ** one or more matching characters, enter those matching characters into ** zInit[]. The re_match() routine can then search ahead in the input ** string looking for the initial match without having to run the whole ** regex engine over the string. Do not worry about trying to match ** unicode characters beyond plane 0 - those are very rare and this is ** just an optimization. */ if( pRe->aOp[0]==RE_OP_ANYSTAR && !noCase ){ for(j=0, i=1; j<(int)sizeof(pRe->zInit)-2 && pRe->aOp[i]==RE_OP_MATCH; i++){ unsigned x = pRe->aArg[i]; if( x<=0x7f ){ pRe->zInit[j++] = (unsigned char)x; }else if( x<=0x7ff ){ pRe->zInit[j++] = (unsigned char)(0xc0 | (x>>6)); pRe->zInit[j++] = 0x80 | (x&0x3f); }else if( x<=0xffff ){ pRe->zInit[j++] = (unsigned char)(0xe0 | (x>>12)); pRe->zInit[j++] = 0x80 | ((x>>6)&0x3f); pRe->zInit[j++] = 0x80 | (x&0x3f); }else{ break; } } if( j>0 && pRe->zInit[j-1]==0 ) j--; pRe->nInit = j; } return pRe->zErr; } /* ** Implementation of the regexp() SQL function. This function implements ** the build-in REGEXP operator. The first argument to the function is the ** pattern and the second argument is the string. So, the SQL statements: ** ** A REGEXP B ** ** is implemented as regexp(B,A). */ static void re_sql_func( sqlite3_context *context, int argc, sqlite3_value **argv ){ ReCompiled *pRe; /* Compiled regular expression */ const char *zPattern; /* The regular expression */ const unsigned char *zStr;/* String being searched */ const char *zErr; /* Compile error message */ int setAux = 0; /* True to invoke sqlite3_set_auxdata() */ (void)argc; /* Unused */ pRe = sqlite3_get_auxdata(context, 0); if( pRe==0 ){ zPattern = (const char*)sqlite3_value_text(argv[0]); if( zPattern==0 ) return; zErr = re_compile(&pRe, zPattern, sqlite3_user_data(context)!=0); if( zErr ){ re_free(pRe); sqlite3_result_error(context, zErr, -1); return; } if( pRe==0 ){ sqlite3_result_error_nomem(context); return; } setAux = 1; } zStr = (const unsigned char*)sqlite3_value_text(argv[1]); if( zStr!=0 ){ sqlite3_result_int(context, re_match(pRe, zStr, -1)); } if( setAux ){ sqlite3_set_auxdata(context, 0, pRe, (void(*)(void*))re_free); } } #if defined(SQLITE_DEBUG) /* ** This function is used for testing and debugging only. It is only available ** if the SQLITE_DEBUG compile-time option is used. ** ** Compile a regular expression and then convert the compiled expression into ** text and return that text. */ static void re_bytecode_func( sqlite3_context *context, int argc, sqlite3_value **argv ){ const char *zPattern; const char *zErr; ReCompiled *pRe; sqlite3_str *pStr; int i; int n; char *z; (void)argc; zPattern = (const char*)sqlite3_value_text(argv[0]); if( zPattern==0 ) return; zErr = re_compile(&pRe, zPattern, sqlite3_user_data(context)!=0); if( zErr ){ re_free(pRe); sqlite3_result_error(context, zErr, -1); return; } if( pRe==0 ){ sqlite3_result_error_nomem(context); return; } pStr = sqlite3_str_new(0); if( pStr==0 ) goto re_bytecode_func_err; if( pRe->nInit>0 ){ sqlite3_str_appendf(pStr, "INIT "); for(i=0; i<pRe->nInit; i++){ sqlite3_str_appendf(pStr, "%02x", pRe->zInit[i]); } sqlite3_str_appendf(pStr, "\n"); } for(i=0; (unsigned)i<pRe->nState; i++){ sqlite3_str_appendf(pStr, "%-8s %4d\n", ReOpName[(unsigned char)pRe->aOp[i]], pRe->aArg[i]); } n = sqlite3_str_length(pStr); z = sqlite3_str_finish(pStr); if( n==0 ){ sqlite3_free(z); }else{ sqlite3_result_text(context, z, n-1, sqlite3_free); } re_bytecode_func_err: re_free(pRe); } #endif /* SQLITE_DEBUG */ /* ** Invoke this routine to register the regexp() function with the ** SQLite database connection. */ #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_regexp_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ int rc = SQLITE_OK; SQLITE_EXTENSION_INIT2(pApi); (void)pzErrMsg; /* Unused */ rc = sqlite3_create_function(db, "regexp", 2, SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC, 0, re_sql_func, 0, 0); if( rc==SQLITE_OK ){ /* The regexpi(PATTERN,STRING) function is a case-insensitive version ** of regexp(PATTERN,STRING). */ rc = sqlite3_create_function(db, "regexpi", 2, SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC, (void*)db, re_sql_func, 0, 0); #if defined(SQLITE_DEBUG) if( rc==SQLITE_OK ){ rc = sqlite3_create_function(db, "regexp_bytecode", 1, SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC, 0, re_bytecode_func, 0, 0); } #endif /* SQLITE_DEBUG */ } return rc; }