/*
** 2004 April 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.
**
*************************************************************************
** This file contains routines used to translate between UTF-8,
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.cpp 1282 2008-11-13 09:31:33Z LarsPson $
**
** Notes on UTF-8:
**
** Byte-0 Byte-1 Byte-2 Byte-3 Value
** 0xxxxxxx 00000000 00000000 0xxxxxxx
** 110yyyyy 10xxxxxx 00000000 00000yyy yyxxxxxx
** 1110zzzz 10yyyyyy 10xxxxxx 00000000 zzzzyyyy yyxxxxxx
** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx
**
**
** Notes on UTF-16: (with wwww+1==uuuuu)
**
** Word-0 Word-1 Value
** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx
** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx
**
**
** BOM or Byte Order Mark:
** 0xff 0xfe little-endian utf-16 follows
** 0xfe 0xff big-endian utf-16 follows
**
*/
#include "sqliteInt.h"
#include <assert.h>
#include "vdbeInt.h"
/*
** The following constant value is used by the SQLITE_BIGENDIAN and
** SQLITE_LITTLEENDIAN macros.
*/
const int sqlite3one = 1;
/*
** This lookup table is used to help decode the first byte of
** a multi-byte UTF8 character.
*/
static const unsigned char sqlite3UtfTrans1[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
};
#define WRITE_UTF8(zOut, c) { \
if( c<0x00080 ){ \
*zOut++ = (c&0xFF); \
} \
else if( c<0x00800 ){ \
*zOut++ = 0xC0 + ((c>>6)&0x1F); \
*zOut++ = 0x80 + (c & 0x3F); \
} \
else if( c<0x10000 ){ \
*zOut++ = 0xE0 + ((c>>12)&0x0F); \
*zOut++ = 0x80 + ((c>>6) & 0x3F); \
*zOut++ = 0x80 + (c & 0x3F); \
}else{ \
*zOut++ = 0xF0 + ((c>>18) & 0x07); \
*zOut++ = 0x80 + ((c>>12) & 0x3F); \
*zOut++ = 0x80 + ((c>>6) & 0x3F); \
*zOut++ = 0x80 + (c & 0x3F); \
} \
}
#define WRITE_UTF16LE(zOut, c) { \
if( c<=0xFFFF ){ \
*zOut++ = (c&0x00FF); \
*zOut++ = ((c>>8)&0x00FF); \
}else{ \
*zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
*zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \
*zOut++ = (c&0x00FF); \
*zOut++ = (0x00DC + ((c>>8)&0x03)); \
} \
}
#define WRITE_UTF16BE(zOut, c) { \
if( c<=0xFFFF ){ \
*zOut++ = ((c>>8)&0x00FF); \
*zOut++ = (c&0x00FF); \
}else{ \
*zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \
*zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
*zOut++ = (0x00DC + ((c>>8)&0x03)); \
*zOut++ = (c&0x00FF); \
} \
}
#define READ_UTF16LE(zIn, c){ \
c = (*zIn++); \
c += ((*zIn++)<<8); \
if( c>=0xD800 && c<0xE000 ){ \
int c2 = (*zIn++); \
c2 += ((*zIn++)<<8); \
c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
if( (c & 0xFFFF0000)==0 ) c = 0xFFFD; \
} \
}
#define READ_UTF16BE(zIn, c){ \
c = ((*zIn++)<<8); \
c += (*zIn++); \
if( c>=0xD800 && c<0xE000 ){ \
int c2 = ((*zIn++)<<8); \
c2 += (*zIn++); \
c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
if( (c & 0xFFFF0000)==0 ) c = 0xFFFD; \
} \
}
/*
** Translate a single UTF-8 character. Return the unicode value.
**
** During translation, assume that the byte that zTerm points
** is a 0x00.
**
** Write a pointer to the next unread byte back into *pzNext.
**
** Notes On Invalid UTF-8:
**
** * This routine never allows a 7-bit character (0x00 through 0x7f) to
** be encoded as a multi-byte character. Any multi-byte character that
** attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
**
** * This routine never allows a UTF16 surrogate value to be encoded.
** If a multi-byte character attempts to encode a value between
** 0xd800 and 0xe000 then it is rendered as 0xfffd.
**
** * Bytes in the range of 0x80 through 0xbf which occur as the first
** byte of a character are interpreted as single-byte characters
** and rendered as themselves even though they are technically
** invalid characters.
**
** * This routine accepts an infinite number of different UTF8 encodings
** for unicode values 0x80 and greater. It do not change over-length
** encodings to 0xfffd as some systems recommend.
*/
int sqlite3Utf8Read(
const unsigned char *z, /* First byte of UTF-8 character */
const unsigned char *zTerm, /* Pretend this byte is 0x00 */
const unsigned char **pzNext /* Write first byte past UTF-8 char here */
){
int c = *(z++);
if( c>=0xc0 ){
c = sqlite3UtfTrans1[c-0xc0];
while( z!=zTerm && (*z & 0xc0)==0x80 ){
c = (c<<6) + (0x3f & *(z++));
}
if( c<0x80
|| (c&0xFFFFF800)==0xD800
|| (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; }
}
*pzNext = z;
return c;
}
/*
** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
*/
/* #define TRANSLATE_TRACE 1 */
#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
unsigned char zShort[NBFS]; /* Temporary short output buffer */
int len; /* Maximum length of output string in bytes */
unsigned char *zOut; /* Output buffer */
unsigned char *zIn; /* Input iterator */
unsigned char *zTerm; /* End of input */
unsigned char *z; /* Output iterator */
unsigned int c;
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( pMem->flags&MEM_Str );
assert( pMem->enc!=desiredEnc );
assert( pMem->enc!=0 );
assert( pMem->n>=0 );
#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
{
char zBuf[100];
sqlite3VdbeMemPrettyPrint(pMem, zBuf);
fprintf(stderr, "INPUT: %s\n", zBuf);
}
#endif
/* If the translation is between UTF-16 little and big endian, then
** all that is required is to swap the byte order. This case is handled
** differently from the others.
*/
if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){
u8 temp;
int rc;
rc = sqlite3VdbeMemMakeWriteable(pMem);
if( rc!=SQLITE_OK ){
assert( rc==SQLITE_NOMEM );
return SQLITE_NOMEM;
}
zIn = (u8*)pMem->z;
zTerm = &zIn[pMem->n];
while( zIn<zTerm ){
temp = *zIn;
*zIn = *(zIn+1);
zIn++;
*zIn++ = temp;
}
pMem->enc = desiredEnc;
goto translate_out;
}
/* Set len to the maximum number of bytes required in the output buffer. */
if( desiredEnc==SQLITE_UTF8 ){
/* When converting from UTF-16, the maximum growth results from
** translating a 2-byte character to a 4-byte UTF-8 character.
** A single byte is required for the output string
** nul-terminator.
*/
len = pMem->n * 2 + 1;
}else{
/* When converting from UTF-8 to UTF-16 the maximum growth is caused
** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
** character. Two bytes are required in the output buffer for the
** nul-terminator.
*/
len = pMem->n * 2 + 2;
}
/* Set zIn to point at the start of the input buffer and zTerm to point 1
** byte past the end.
**
** Variable zOut is set to point at the output buffer. This may be space
** obtained from sqlite3_malloc(), or Mem.zShort, if it large enough and
** not in use, or the zShort array on the stack (see above).
*/
zIn = (u8*)pMem->z;
zTerm = &zIn[pMem->n];
if( len>NBFS ){
zOut = (unsigned char*)sqlite3DbMallocRaw(pMem->db, len);
if( !zOut ){
return SQLITE_NOMEM;
}
}else{
zOut = zShort;
}
z = zOut;
if( pMem->enc==SQLITE_UTF8 ){
if( desiredEnc==SQLITE_UTF16LE ){
/* UTF-8 -> UTF-16 Little-endian */
while( zIn<zTerm ){
c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
WRITE_UTF16LE(z, c);
}
}else{
assert( desiredEnc==SQLITE_UTF16BE );
/* UTF-8 -> UTF-16 Big-endian */
while( zIn<zTerm ){
c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
WRITE_UTF16BE(z, c);
}
}
pMem->n = z - zOut;
*z++ = 0;
}else{
assert( desiredEnc==SQLITE_UTF8 );
if( pMem->enc==SQLITE_UTF16LE ){
/* UTF-16 Little-endian -> UTF-8 */
while( zIn<zTerm ){
READ_UTF16LE(zIn, c);
WRITE_UTF8(z, c);
}
}else{
/* UTF-16 Little-endian -> UTF-8 */
while( zIn<zTerm ){
READ_UTF16BE(zIn, c);
WRITE_UTF8(z, c);
}
}
pMem->n = z - zOut;
}
*z = 0;
assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
sqlite3VdbeMemRelease(pMem);
pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short);
pMem->enc = desiredEnc;
if( zOut==zShort ){
memcpy(pMem->zShort, zOut, len);
zOut = (u8*)pMem->zShort;
pMem->flags |= (MEM_Term|MEM_Short);
}else{
pMem->flags |= (MEM_Term|MEM_Dyn);
}
pMem->z = (char*)zOut;
translate_out:
#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
{
char zBuf[100];
sqlite3VdbeMemPrettyPrint(pMem, zBuf);
fprintf(stderr, "OUTPUT: %s\n", zBuf);
}
#endif
return SQLITE_OK;
}
/*
** This routine checks for a byte-order mark at the beginning of the
** UTF-16 string stored in *pMem. If one is present, it is removed and
** the encoding of the Mem adjusted. This routine does not do any
** byte-swapping, it just sets Mem.enc appropriately.
**
** The allocation (static, dynamic etc.) and encoding of the Mem may be
** changed by this function.
*/
int sqlite3VdbeMemHandleBom(Mem *pMem){
int rc = SQLITE_OK;
u8 bom = 0;
if( pMem->n<0 || pMem->n>1 ){
u8 b1 = *(u8 *)pMem->z;
u8 b2 = *(((u8 *)pMem->z) + 1);
if( b1==0xFE && b2==0xFF ){
bom = SQLITE_UTF16BE;
}
if( b1==0xFF && b2==0xFE ){
bom = SQLITE_UTF16LE;
}
}
if( bom ){
/* This function is called as soon as a string is stored in a Mem*,
** from within sqlite3VdbeMemSetStr(). At that point it is not possible
** for the string to be stored in Mem.zShort, or for it to be stored
** in dynamic memory with no destructor.
*/
assert( !(pMem->flags&MEM_Short) );
assert( !(pMem->flags&MEM_Dyn) || pMem->xDel );
if( pMem->flags & MEM_Dyn ){
void (*xDel)(void*) = pMem->xDel;
char *z = pMem->z;
pMem->z = 0;
pMem->xDel = 0;
rc = sqlite3VdbeMemSetStr(pMem, &z[2], pMem->n-2, bom,
SQLITE_TRANSIENT);
xDel(z);
}else{
rc = sqlite3VdbeMemSetStr(pMem, &pMem->z[2], pMem->n-2, bom,
SQLITE_TRANSIENT);
}
}
return rc;
}
#endif /* SQLITE_OMIT_UTF16 */
/*
** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
** return the number of unicode characters in pZ up to (but not including)
** the first 0x00 byte. If nByte is not less than zero, return the
** number of unicode characters in the first nByte of pZ (or up to
** the first 0x00, whichever comes first).
*/
int sqlite3Utf8CharLen(const char *zIn, int nByte){
int r = 0;
const u8 *z = (const u8*)zIn;
const u8 *zTerm;
if( nByte>=0 ){
zTerm = &z[nByte];
}else{
zTerm = (const u8*)(-1);
}
assert( z<=zTerm );
while( *z!=0 && z<zTerm ){
SQLITE_SKIP_UTF8(z);
r++;
}
return r;
}
/* This test function is not currently used by the automated test-suite.
** Hence it is only available in debug builds.
*/
#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
/*
** Translate UTF-8 to UTF-8.
**
** This has the effect of making sure that the string is well-formed
** UTF-8. Miscoded characters are removed.
**
** The translation is done in-place (since it is impossible for the
** correct UTF-8 encoding to be longer than a malformed encoding).
*/
int sqlite3Utf8To8(unsigned char *zIn){
unsigned char *zOut = zIn;
unsigned char *zStart = zIn;
unsigned char *zTerm;
u32 c;
while( zIn[0] ){
c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn);
if( c!=0xfffd ){
WRITE_UTF8(zOut, c);
}
}
*zOut = 0;
return zOut - zStart;
}
#endif
#ifndef SQLITE_OMIT_UTF16
/*
** Convert a UTF-16 string in the native encoding into a UTF-8 string.
** Memory to hold the UTF-8 string is obtained from sqlite3_malloc and must
** be freed by the calling function.
**
** NULL is returned if there is an allocation error.
*/
char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte){
Mem m;
memset(&m, 0, sizeof(m));
m.db = db;
sqlite3VdbeMemSetStr(&m, (const char*)z, nByte, SQLITE_UTF16NATIVE, SQLITE_STATIC);
sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8);
if( db->mallocFailed ){
sqlite3VdbeMemRelease(&m);
m.z = 0;
}
assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
return (m.flags & MEM_Dyn)!=0 ? m.z : sqlite3DbStrDup(db, m.z);
}
/*
** pZ is a UTF-16 encoded unicode string. If nChar is less than zero,
** return the number of bytes up to (but not including), the first pair
** of consecutive 0x00 bytes in pZ. If nChar is not less than zero,
** then return the number of bytes in the first nChar unicode characters
** in pZ (or up until the first pair of 0x00 bytes, whichever comes first).
*/
int sqlite3Utf16ByteLen(const void *zIn, int nChar){
unsigned int c = 1;
char const *z = (const char*)zIn;
int n = 0;
if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
/* Using an "if (SQLITE_UTF16NATIVE==SQLITE_UTF16BE)" construct here
** and in other parts of this file means that at one branch will
** not be covered by coverage testing on any single host. But coverage
** will be complete if the tests are run on both a little-endian and
** big-endian host. Because both the UTF16NATIVE and SQLITE_UTF16BE
** macros are constant at compile time the compiler can determine
** which branch will be followed. It is therefore assumed that no runtime
** penalty is paid for this "if" statement.
*/
while( c && ((nChar<0) || n<nChar) ){
READ_UTF16BE(z, c);
n++;
}
}else{
while( c && ((nChar<0) || n<nChar) ){
READ_UTF16LE(z, c);
n++;
}
}
return (z-(char const *)zIn)-((c==0)?2:0);
}
#if defined(SQLITE_TEST)
/*
** This routine is called from the TCL test function "translate_selftest".
** It checks that the primitives for serializing and deserializing
** characters in each encoding are inverses of each other.
*/
void sqlite3UtfSelfTest(){
unsigned int i, t;
unsigned char zBuf[20];
unsigned char *z;
unsigned char *zTerm;
int n;
unsigned int c;
for(i=0; i<0x00110000; i++){
z = zBuf;
WRITE_UTF8(z, i);
n = z-zBuf;
z[0] = 0;
zTerm = z;
z = zBuf;
c = sqlite3Utf8Read(z, zTerm, (const u8**)&z);
t = i;
if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
assert( c==t );
assert( (z-zBuf)==n );
}
for(i=0; i<0x00110000; i++){
if( i>=0xD800 && i<0xE000 ) continue;
z = zBuf;
WRITE_UTF16LE(z, i);
n = z-zBuf;
z[0] = 0;
z = zBuf;
READ_UTF16LE(z, c);
assert( c==i );
assert( (z-zBuf)==n );
}
for(i=0; i<0x00110000; i++){
if( i>=0xD800 && i<0xE000 ) continue;
z = zBuf;
WRITE_UTF16BE(z, i);
n = z-zBuf;
z[0] = 0;
z = zBuf;
READ_UTF16BE(z, c);
assert( c==i );
assert( (z-zBuf)==n );
}
}
#endif /* SQLITE_TEST */
#endif /* SQLITE_OMIT_UTF16 */