/*
Basic UTF-8 manipulation routines
by Jeff Bezanson
placed in the public domain Fall 2005
This code is designed to provide the utilities you need to manipulate
UTF-8 as an internal string encoding. These functions do not perform the
error checking normally needed when handling UTF-8 data, so if you happen
to be from the Unicode Consortium you will want to flay me alive.
I do this because error checking can be performed at the boundaries (I/O),
with these routines reserved for higher performance on data known to be
valid.
*/
#ifdef _WIN32
#include <windows.h>
#undef min
#undef max
#endif
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <algorithm>
#include <string>
#include "common/common_types.h"
#include "common/utf8.h"
// is start of UTF sequence
inline bool isutf(char c) {
return (c & 0xC0) != 0x80;
}
static const u32 offsetsFromUTF8[6] = {
0x00000000UL, 0x00003080UL, 0x000E2080UL,
0x03C82080UL, 0xFA082080UL, 0x82082080UL
};
static const u8 trailingBytesForUTF8[256] = {
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5,
};
/* returns length of next utf-8 sequence */
int u8_seqlen(const char *s)
{
return trailingBytesForUTF8[(unsigned int)(unsigned char)s[0]] + 1;
}
/* conversions without error checking
only works for valid UTF-8, i.e. no 5- or 6-byte sequences
srcsz = source size in bytes, or -1 if 0-terminated
sz = dest size in # of wide characters
returns # characters converted
dest will always be L'\0'-terminated, even if there isn't enough room
for all the characters.
if sz = srcsz+1 (i.e. 4*srcsz+4 bytes), there will always be enough space.
*/
int u8_toucs(u32 *dest, int sz, const char *src, int srcsz)
{
u32 ch;
const char *src_end = src + srcsz;
int nb;
int i=0;
while (i < sz-1) {
nb = trailingBytesForUTF8[(unsigned char)*src];
if (srcsz == -1) {
if (*src == 0)
goto done_toucs;
}
else {
if (src + nb >= src_end)
goto done_toucs;
}
ch = 0;
switch (nb) {
/* these fall through deliberately */
case 3: ch += (unsigned char)*src++; ch <<= 6;
case 2: ch += (unsigned char)*src++; ch <<= 6;
case 1: ch += (unsigned char)*src++; ch <<= 6;
case 0: ch += (unsigned char)*src++;
}
ch -= offsetsFromUTF8[nb];
dest[i++] = ch;
}
done_toucs:
dest[i] = 0;
return i;
}
/* srcsz = number of source characters, or -1 if 0-terminated
sz = size of dest buffer in bytes
returns # characters converted
dest will only be '\0'-terminated if there is enough space. this is
for consistency; imagine there are 2 bytes of space left, but the next
character requires 3 bytes. in this case we could NUL-terminate, but in
general we can't when there's insufficient space. therefore this function
only NUL-terminates if all the characters fit, and there's space for
the NUL as well.
the destination string will never be bigger than the source string.
*/
int u8_toutf8(char *dest, int sz, u32 *src, int srcsz)
{
u32 ch;
int i = 0;
char *dest_end = dest + sz;
while (srcsz<0 ? src[i]!=0 : i < srcsz) {
ch = src[i];
if (ch < 0x80) {
if (dest >= dest_end)
return i;
*dest++ = (char)ch;
}
else if (ch < 0x800) {
if (dest >= dest_end-1)
return i;
*dest++ = (ch>>6) | 0xC0;
*dest++ = (ch & 0x3F) | 0x80;
}
else if (ch < 0x10000) {
if (dest >= dest_end-2)
return i;
*dest++ = (ch>>12) | 0xE0;
*dest++ = ((ch>>6) & 0x3F) | 0x80;
*dest++ = (ch & 0x3F) | 0x80;
}
else if (ch < 0x110000) {
if (dest >= dest_end-3)
return i;
*dest++ = (ch>>18) | 0xF0;
*dest++ = ((ch>>12) & 0x3F) | 0x80;
*dest++ = ((ch>>6) & 0x3F) | 0x80;
*dest++ = (ch & 0x3F) | 0x80;
}
i++;
}
if (dest < dest_end)
*dest = '\0';
return i;
}
int u8_wc_toutf8(char *dest, u32 ch)
{
if (ch < 0x80) {
dest[0] = (char)ch;
return 1;
}
if (ch < 0x800) {
dest[0] = (ch>>6) | 0xC0;
dest[1] = (ch & 0x3F) | 0x80;
return 2;
}
if (ch < 0x10000) {
dest[0] = (ch>>12) | 0xE0;
dest[1] = ((ch>>6) & 0x3F) | 0x80;
dest[2] = (ch & 0x3F) | 0x80;
return 3;
}
if (ch < 0x110000) {
dest[0] = (ch>>18) | 0xF0;
dest[1] = ((ch>>12) & 0x3F) | 0x80;
dest[2] = ((ch>>6) & 0x3F) | 0x80;
dest[3] = (ch & 0x3F) | 0x80;
return 4;
}
return 0;
}
/* charnum => byte offset */
int u8_offset(const char *str, int charnum)
{
int offs=0;
while (charnum > 0 && str[offs]) {
(void)(isutf(str[++offs]) || isutf(str[++offs]) ||
isutf(str[++offs]) || ++offs);
charnum--;
}
return offs;
}
/* byte offset => charnum */
int u8_charnum(const char *s, int offset)
{
int charnum = 0, offs=0;
while (offs < offset && s[offs]) {
(void)(isutf(s[++offs]) || isutf(s[++offs]) ||
isutf(s[++offs]) || ++offs);
charnum++;
}
return charnum;
}
/* number of characters */
int u8_strlen(const char *s)
{
int count = 0;
int i = 0;
while (u8_nextchar(s, &i) != 0)
count++;
return count;
}
/* reads the next utf-8 sequence out of a string, updating an index */
u32 u8_nextchar(const char *s, int *i)
{
u32 ch = 0;
int sz = 0;
do {
ch <<= 6;
ch += (unsigned char)s[(*i)++];
sz++;
} while (s[*i] && !isutf(s[*i]));
ch -= offsetsFromUTF8[sz-1];
return ch;
}
void u8_inc(const char *s, int *i)
{
(void)(isutf(s[++(*i)]) || isutf(s[++(*i)]) ||
isutf(s[++(*i)]) || ++(*i));
}
void u8_dec(const char *s, int *i)
{
(void)(isutf(s[--(*i)]) || isutf(s[--(*i)]) ||
isutf(s[--(*i)]) || --(*i));
}
int octal_digit(char c)
{
return (c >= '0' && c <= '7');
}
int hex_digit(char c)
{
return ((c >= '0' && c <= '9') ||
(c >= 'A' && c <= 'F') ||
(c >= 'a' && c <= 'f'));
}
/* assumes that src points to the character after a backslash
returns number of input characters processed */
int u8_read_escape_sequence(const char *str, u32 *dest)
{
u32 ch;
char digs[9]="\0\0\0\0\0\0\0\0";
int dno=0, i=1;
ch = (u32)str[0]; /* take literal character */
if (str[0] == 'n')
ch = L'\n';
else if (str[0] == 't')
ch = L'\t';
else if (str[0] == 'r')
ch = L'\r';
else if (str[0] == 'b')
ch = L'\b';
else if (str[0] == 'f')
ch = L'\f';
else if (str[0] == 'v')
ch = L'\v';
else if (str[0] == 'a')
ch = L'\a';
else if (octal_digit(str[0])) {
i = 0;
do {
digs[dno++] = str[i++];
} while (octal_digit(str[i]) && dno < 3);
ch = strtol(digs, NULL, 8);
}
else if (str[0] == 'x') {
while (hex_digit(str[i]) && dno < 2) {
digs[dno++] = str[i++];
}
if (dno > 0)
ch = strtol(digs, NULL, 16);
}
else if (str[0] == 'u') {
while (hex_digit(str[i]) && dno < 4) {
digs[dno++] = str[i++];
}
if (dno > 0)
ch = strtol(digs, NULL, 16);
}
else if (str[0] == 'U') {
while (hex_digit(str[i]) && dno < 8) {
digs[dno++] = str[i++];
}
if (dno > 0)
ch = strtol(digs, NULL, 16);
}
*dest = ch;
return i;
}
/* convert a string with literal \uxxxx or \Uxxxxxxxx characters to UTF-8
example: u8_unescape(mybuf, 256, "hello\\u220e")
note the double backslash is needed if called on a C string literal */
int u8_unescape(char *buf, int sz, char *src)
{
int c=0, amt;
u32 ch;
char temp[4];
while (*src && c < sz) {
if (*src == '\\') {
src++;
amt = u8_read_escape_sequence(src, &ch);
}
else {
ch = (u32)*src;
amt = 1;
}
src += amt;
amt = u8_wc_toutf8(temp, ch);
if (amt > sz-c)
break;
memcpy(&buf[c], temp, amt);
c += amt;
}
if (c < sz)
buf[c] = '\0';
return c;
}
const char *u8_strchr(const char *s, u32 ch, int *charn)
{
int i = 0, lasti=0;
u32 c;
*charn = 0;
while (s[i]) {
c = u8_nextchar(s, &i);
if (c == ch) {
return &s[lasti];
}
lasti = i;
(*charn)++;
}
return NULL;
}
const char *u8_memchr(const char *s, u32 ch, size_t sz, int *charn)
{
u32 i = 0, lasti=0;
u32 c;
int csz;
*charn = 0;
while (i < sz) {
c = csz = 0;
do {
c <<= 6;
c += (unsigned char)s[i++];
csz++;
} while (i < sz && !isutf(s[i]));
c -= offsetsFromUTF8[csz-1];
if (c == ch) {
return &s[lasti];
}
lasti = i;
(*charn)++;
}
return NULL;
}
int u8_is_locale_utf8(const char *locale)
{
/* this code based on libutf8 */
const char* cp = locale;
for (; *cp != '\0' && *cp != '@' && *cp != '+' && *cp != ','; cp++) {
if (*cp == '.') {
const char* encoding = ++cp;
for (; *cp != '\0' && *cp != '@' && *cp != '+' && *cp != ','; cp++)
;
if ((cp-encoding == 5 && !strncmp(encoding, "UTF-8", 5))
|| (cp-encoding == 4 && !strncmp(encoding, "utf8", 4)))
return 1; /* it's UTF-8 */
break;
}
}
return 0;
}
int UTF8StringNonASCIICount(const char *utf8string) {
UTF8 utf(utf8string);
int count = 0;
while (!utf.end()) {
int c = utf.next();
if (c > 127)
++count;
}
return count;
}
bool UTF8StringHasNonASCII(const char *utf8string) {
return UTF8StringNonASCIICount(utf8string) > 0;
}
#ifdef _WIN32
std::string ConvertWStringToUTF8(const wchar_t *wstr) {
int len = (int)wcslen(wstr);
int size = (int)WideCharToMultiByte(CP_UTF8, 0, wstr, len, 0, 0, NULL, NULL);
std::string s;
s.resize(size);
if (size > 0) {
WideCharToMultiByte(CP_UTF8, 0, wstr, len, &s[0], size, NULL, NULL);
}
return s;
}
std::string ConvertWStringToUTF8(const std::wstring &wstr) {
int len = (int)wstr.size();
int size = (int)WideCharToMultiByte(CP_UTF8, 0, wstr.c_str(), len, 0, 0, NULL, NULL);
std::string s;
s.resize(size);
if (size > 0) {
WideCharToMultiByte(CP_UTF8, 0, wstr.c_str(), len, &s[0], size, NULL, NULL);
}
return s;
}
void ConvertUTF8ToWString(wchar_t *dest, size_t destSize, const std::string &source) {
int len = (int)source.size();
int size = (int)MultiByteToWideChar(CP_UTF8, 0, source.c_str(), len, NULL, 0);
MultiByteToWideChar(CP_UTF8, 0, source.c_str(), len, dest, std::min((int)destSize, size));
}
std::wstring ConvertUTF8ToWString(const std::string &source) {
int len = (int)source.size();
int size = (int)MultiByteToWideChar(CP_UTF8, 0, source.c_str(), len, NULL, 0);
std::wstring str;
str.resize(size);
if (size > 0) {
MultiByteToWideChar(CP_UTF8, 0, source.c_str(), len, &str[0], size);
}
return str;
}
#endif
