diff options
Diffstat (limited to 'src/func.c')
| -rw-r--r-- | src/func.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/func.c b/src/func.c index 9a62470a0..619c81430 100644 --- a/src/func.c +++ b/src/func.c @@ -1224,6 +1224,39 @@ static void hexFunc( } /* +** The unhex() function. Interpret the argument as text. If it consists +** of an even number of hexadecimal digits, return the equivalent blob. +** Otherwise, return NULL. +*/ +static void unhexFunc( + sqlite3_context *pCtx, + int argc, + sqlite3_value **argv +){ + const u8 *zHex = sqlite3_value_text(argv[0]); + int nHex = sqlite3_value_bytes(argv[0]); + if( zHex && (nHex%2)==0 ){ + u8 *pBlob = contextMalloc(pCtx, (nHex/2)+1); + if( pBlob ){ + const u8 *zEnd = &zHex[nHex]; + u8 *p = pBlob; + while( zHex<zEnd ){ + unsigned char c = *(zHex++); + unsigned char d = *(zHex++); + if( !sqlite3Isxdigit(c) || !sqlite3Isxdigit(d) ){ + sqlite3_free(pBlob); + return; + }else{ + *(p++) = (sqlite3HexToInt(c)<<4) | sqlite3HexToInt(d); + } + } + sqlite3_result_blob(pCtx, pBlob, (p - pBlob), sqlite3_free); + } + } +} + + +/* ** The zeroblob(N) function returns a zero-filled blob of size N bytes. */ static void zeroblobFunc( @@ -2287,6 +2320,7 @@ void sqlite3RegisterBuiltinFunctions(void){ FUNCTION(upper, 1, 0, 0, upperFunc ), FUNCTION(lower, 1, 0, 0, lowerFunc ), FUNCTION(hex, 1, 0, 0, hexFunc ), + FUNCTION(unhex, 1, 0, 0, unhexFunc ), INLINE_FUNC(ifnull, 2, INLINEFUNC_coalesce, 0 ), VFUNCTION(random, 0, 0, 0, randomFunc ), VFUNCTION(randomblob, 1, 0, 0, randomBlob ), |