diff options
Diffstat (limited to 'lib/libsqlite3/src/func.c')
-rw-r--r-- | lib/libsqlite3/src/func.c | 120 |
1 files changed, 76 insertions, 44 deletions
diff --git a/lib/libsqlite3/src/func.c b/lib/libsqlite3/src/func.c index e56561e4ecb..d4655ad7e96 100644 --- a/lib/libsqlite3/src/func.c +++ b/lib/libsqlite3/src/func.c @@ -169,6 +169,56 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ } /* +** Implementation of the instr() function. +** +** instr(haystack,needle) finds the first occurrence of needle +** in haystack and returns the number of previous characters plus 1, +** or 0 if needle does not occur within haystack. +** +** If both haystack and needle are BLOBs, then the result is one more than +** the number of bytes in haystack prior to the first occurrence of needle, +** or 0 if needle never occurs in haystack. +*/ +static void instrFunc( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + const unsigned char *zHaystack; + const unsigned char *zNeedle; + int nHaystack; + int nNeedle; + int typeHaystack, typeNeedle; + int N = 1; + int isText; + + UNUSED_PARAMETER(argc); + typeHaystack = sqlite3_value_type(argv[0]); + typeNeedle = sqlite3_value_type(argv[1]); + if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return; + nHaystack = sqlite3_value_bytes(argv[0]); + nNeedle = sqlite3_value_bytes(argv[1]); + if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){ + zHaystack = sqlite3_value_blob(argv[0]); + zNeedle = sqlite3_value_blob(argv[1]); + isText = 0; + }else{ + zHaystack = sqlite3_value_text(argv[0]); + zNeedle = sqlite3_value_text(argv[1]); + isText = 1; + } + while( nNeedle<=nHaystack && memcmp(zHaystack, zNeedle, nNeedle)!=0 ){ + N++; + do{ + nHaystack--; + zHaystack++; + }while( isText && (zHaystack[0]&0xc0)==0x80 ); + } + if( nNeedle>nHaystack ) N = 0; + sqlite3_result_int(context, N); +} + +/* ** Implementation of the substr() function. ** ** substr(x,p1,p2) returns p2 characters of x[] beginning with p1. @@ -367,33 +417,14 @@ static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ } } - -#if 0 /* This function is never used. */ -/* -** The COALESCE() and IFNULL() functions used to be implemented as shown -** here. But now they are implemented as VDBE code so that unused arguments -** do not have to be computed. This legacy implementation is retained as -** comment. -*/ /* -** Implementation of the IFNULL(), NVL(), and COALESCE() functions. -** All three do the same thing. They return the first non-NULL -** argument. +** The COALESCE() and IFNULL() functions are implemented as VDBE code so +** that unused argument values do not have to be computed. However, we +** still need some kind of function implementation for this routines in +** the function table. That function implementation will never be called +** so it doesn't matter what the implementation is. We might as well use +** the "version()" function as a substitute. */ -static void ifnullFunc( - sqlite3_context *context, - int argc, - sqlite3_value **argv -){ - int i; - for(i=0; i<argc; i++){ - if( SQLITE_NULL!=sqlite3_value_type(argv[i]) ){ - sqlite3_result_value(context, argv[i]); - break; - } - } -} -#endif /* NOT USED */ #define ifnullFunc versionFunc /* Substitute function - never called */ /* @@ -512,7 +543,7 @@ struct compareInfo { ** whereas only characters less than 0x80 do in ASCII. */ #if defined(SQLITE_EBCDIC) -# define sqlite3Utf8Read(A,C) (*(A++)) +# define sqlite3Utf8Read(A) (*((*A)++)) # define GlogUpperToLower(A) A = sqlite3UpperToLower[A] #else # define GlogUpperToLower(A) if( !((A)&~0x7f) ){ A = sqlite3UpperToLower[A]; } @@ -569,18 +600,18 @@ static int patternCompare( u8 noCase = pInfo->noCase; int prevEscape = 0; /* True if the previous character was 'escape' */ - while( (c = sqlite3Utf8Read(zPattern,&zPattern))!=0 ){ - if( !prevEscape && c==matchAll ){ - while( (c=sqlite3Utf8Read(zPattern,&zPattern)) == matchAll + while( (c = sqlite3Utf8Read(&zPattern))!=0 ){ + if( c==matchAll && !prevEscape ){ + while( (c=sqlite3Utf8Read(&zPattern)) == matchAll || c == matchOne ){ - if( c==matchOne && sqlite3Utf8Read(zString, &zString)==0 ){ + if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ return 0; } } if( c==0 ){ return 1; }else if( c==esc ){ - c = sqlite3Utf8Read(zPattern, &zPattern); + c = sqlite3Utf8Read(&zPattern); if( c==0 ){ return 0; } @@ -592,25 +623,25 @@ static int patternCompare( } return *zString!=0; } - while( (c2 = sqlite3Utf8Read(zString,&zString))!=0 ){ + while( (c2 = sqlite3Utf8Read(&zString))!=0 ){ if( noCase ){ GlogUpperToLower(c2); GlogUpperToLower(c); while( c2 != 0 && c2 != c ){ - c2 = sqlite3Utf8Read(zString, &zString); + c2 = sqlite3Utf8Read(&zString); GlogUpperToLower(c2); } }else{ while( c2 != 0 && c2 != c ){ - c2 = sqlite3Utf8Read(zString, &zString); + c2 = sqlite3Utf8Read(&zString); } } if( c2==0 ) return 0; if( patternCompare(zPattern,zString,pInfo,esc) ) return 1; } return 0; - }else if( !prevEscape && c==matchOne ){ - if( sqlite3Utf8Read(zString, &zString)==0 ){ + }else if( c==matchOne && !prevEscape ){ + if( sqlite3Utf8Read(&zString)==0 ){ return 0; } }else if( c==matchSet ){ @@ -618,20 +649,20 @@ static int patternCompare( assert( esc==0 ); /* This only occurs for GLOB, not LIKE */ seen = 0; invert = 0; - c = sqlite3Utf8Read(zString, &zString); + c = sqlite3Utf8Read(&zString); if( c==0 ) return 0; - c2 = sqlite3Utf8Read(zPattern, &zPattern); + c2 = sqlite3Utf8Read(&zPattern); if( c2=='^' ){ invert = 1; - c2 = sqlite3Utf8Read(zPattern, &zPattern); + c2 = sqlite3Utf8Read(&zPattern); } if( c2==']' ){ if( c==']' ) seen = 1; - c2 = sqlite3Utf8Read(zPattern, &zPattern); + c2 = sqlite3Utf8Read(&zPattern); } while( c2 && c2!=']' ){ if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){ - c2 = sqlite3Utf8Read(zPattern, &zPattern); + c2 = sqlite3Utf8Read(&zPattern); if( c>=prior_c && c<=c2 ) seen = 1; prior_c = 0; }else{ @@ -640,7 +671,7 @@ static int patternCompare( } prior_c = c2; } - c2 = sqlite3Utf8Read(zPattern, &zPattern); + c2 = sqlite3Utf8Read(&zPattern); } if( c2==0 || (seen ^ invert)==0 ){ return 0; @@ -648,7 +679,7 @@ static int patternCompare( }else if( esc==c && !prevEscape ){ prevEscape = 1; }else{ - c2 = sqlite3Utf8Read(zString, &zString); + c2 = sqlite3Utf8Read(&zString); if( noCase ){ GlogUpperToLower(c); GlogUpperToLower(c2); @@ -720,7 +751,7 @@ static void likeFunc( "ESCAPE expression must be a single character", -1); return; } - escape = sqlite3Utf8Read(zEsc, &zEsc); + escape = sqlite3Utf8Read(&zEsc); } if( zA && zB ){ struct compareInfo *pInfo = sqlite3_user_data(context); @@ -1555,6 +1586,7 @@ void sqlite3RegisterGlobalFunctions(void){ AGGREGATE(max, 1, 1, 1, minmaxStep, minMaxFinalize ), FUNCTION2(typeof, 1, 0, 0, typeofFunc, SQLITE_FUNC_TYPEOF), FUNCTION2(length, 1, 0, 0, lengthFunc, SQLITE_FUNC_LENGTH), + FUNCTION(instr, 2, 0, 0, instrFunc ), FUNCTION(substr, 2, 0, 0, substrFunc ), FUNCTION(substr, 3, 0, 0, substrFunc ), FUNCTION(abs, 1, 0, 0, absFunc ), |