1*e4a6e799Ssimonb #include <unistd.h> 2*e4a6e799Ssimonb #include "lt_types.h" 3*e4a6e799Ssimonb 4*e4a6e799Ssimonb // Return number of bytes in the UTF-8 sequence which begins with a given byte. wchar_len(byte b)5*e4a6e799Ssimonbint wchar_len(byte b) { 6*e4a6e799Ssimonb if ((b & 0xE0) == 0xC0) return 2; 7*e4a6e799Ssimonb if ((b & 0xF0) == 0xE0) return 3; 8*e4a6e799Ssimonb if ((b & 0xF8) == 0xF0) return 4; 9*e4a6e799Ssimonb return 1; 10*e4a6e799Ssimonb } 11*e4a6e799Ssimonb store_wchar(byte ** p,wchar ch)12*e4a6e799Ssimonbvoid store_wchar(byte** p, wchar ch) { 13*e4a6e799Ssimonb if (ch < 0x80) { 14*e4a6e799Ssimonb *(*p)++ = (char) ch; 15*e4a6e799Ssimonb } else if (ch < 0x800) { 16*e4a6e799Ssimonb *(*p)++ = (byte) (0xC0 | ((ch >> 6) & 0x1F)); 17*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | (ch & 0x3F)); 18*e4a6e799Ssimonb } else if (ch < 0x10000) { 19*e4a6e799Ssimonb *(*p)++ = (byte) (0xE0 | ((ch >> 12) & 0x0F)); 20*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | ((ch >> 6) & 0x3F)); 21*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | (ch & 0x3F)); 22*e4a6e799Ssimonb } else { 23*e4a6e799Ssimonb *(*p)++ = (byte) (0xF0 | ((ch >> 18) & 0x07)); 24*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | ((ch >> 12) & 0x3F)); 25*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | ((ch >> 6) & 0x3F)); 26*e4a6e799Ssimonb *(*p)++ = (byte) (0x80 | (ch & 0x3F)); 27*e4a6e799Ssimonb } 28*e4a6e799Ssimonb } 29*e4a6e799Ssimonb load_wchar(const byte ** p)30*e4a6e799Ssimonbwchar load_wchar(const byte** p) { 31*e4a6e799Ssimonb wchar ch; 32*e4a6e799Ssimonb switch (wchar_len(**p)) { 33*e4a6e799Ssimonb default: 34*e4a6e799Ssimonb ch = *(*p)++ & 0xFF; 35*e4a6e799Ssimonb break; 36*e4a6e799Ssimonb case 2: 37*e4a6e799Ssimonb ch = (*(*p)++ & 0x1F) << 6; 38*e4a6e799Ssimonb ch |= *(*p)++ & 0x3F; 39*e4a6e799Ssimonb break; 40*e4a6e799Ssimonb case 3: 41*e4a6e799Ssimonb ch = (*(*p)++ & 0x0F) << 12; 42*e4a6e799Ssimonb ch |= (*(*p)++ & 0x3F) << 6; 43*e4a6e799Ssimonb ch |= (*(*p)++ & 0x3F); 44*e4a6e799Ssimonb break; 45*e4a6e799Ssimonb case 4: 46*e4a6e799Ssimonb ch = (*(*p)++ & 0x07) << 18; 47*e4a6e799Ssimonb ch |= (*(*p)++ & 0x3F) << 12; 48*e4a6e799Ssimonb ch |= (*(*p)++ & 0x3F) << 6; 49*e4a6e799Ssimonb ch |= (*(*p)++ & 0x3F); 50*e4a6e799Ssimonb break; 51*e4a6e799Ssimonb } 52*e4a6e799Ssimonb return ch; 53*e4a6e799Ssimonb } 54*e4a6e799Ssimonb read_wchar(int fd)55*e4a6e799Ssimonbwchar read_wchar(int fd) { 56*e4a6e799Ssimonb byte cbuf[UNICODE_MAX_BYTES]; 57*e4a6e799Ssimonb int n = read(fd, &cbuf[0], 1); 58*e4a6e799Ssimonb if (n <= 0) 59*e4a6e799Ssimonb return 0; 60*e4a6e799Ssimonb int len = wchar_len(cbuf[0]); 61*e4a6e799Ssimonb int i; 62*e4a6e799Ssimonb for (i = 1; i < len; ++i) { 63*e4a6e799Ssimonb int n = read(fd, &cbuf[i], 1); 64*e4a6e799Ssimonb if (n != 1) return 0; 65*e4a6e799Ssimonb } 66*e4a6e799Ssimonb const byte* cp = cbuf; 67*e4a6e799Ssimonb wchar ch = load_wchar(&cp); 68*e4a6e799Ssimonb // assert(cp-cbuf == len); 69*e4a6e799Ssimonb return ch; 70*e4a6e799Ssimonb } 71