ref: 46dec712a71b4155f66b40ac92eb796d7e1fab89
dir: /utf.c/
/* * The authors of this software are Rob Pike and Ken Thompson. * Copyright (c) 2002 by Lucent Technologies. * Permission to use, copy, modify, and distribute this software for any * purpose without fee is hereby granted, provided that this entire notice * is included in all copies of any software which is or includes a copy * or modification of this software and in all copies of the supporting * documentation for such software. * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED * WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE * ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE. */ #include <stdlib.h> #include <string.h> #include "utf.h" typedef unsigned char uchar; enum { Bit1 = 7, Bitx = 6, Bit2 = 5, Bit3 = 4, Bit4 = 3, T1 = ((1<<(Bit1+1))-1) ^ 0xFF, /* 0000 0000 */ Tx = ((1<<(Bitx+1))-1) ^ 0xFF, /* 1000 0000 */ T2 = ((1<<(Bit2+1))-1) ^ 0xFF, /* 1100 0000 */ T3 = ((1<<(Bit3+1))-1) ^ 0xFF, /* 1110 0000 */ T4 = ((1<<(Bit4+1))-1) ^ 0xFF, /* 1111 0000 */ Rune1 = (1<<(Bit1+0*Bitx))-1, /* 0000 0000 0111 1111 */ Rune2 = (1<<(Bit2+1*Bitx))-1, /* 0000 0111 1111 1111 */ Rune3 = (1<<(Bit3+2*Bitx))-1, /* 1111 1111 1111 1111 */ Maskx = (1<<Bitx)-1, /* 0011 1111 */ Testx = Maskx ^ 0xFF, /* 1100 0000 */ Bad = Runeerror, }; int chartorune(Rune *rune, const char *str) { int c, c1, c2; long l; /* * one character sequence * 00000-0007F => T1 */ c = *(uchar*)str; if(c < Tx) { *rune = c; return 1; } /* * two character sequence * 0080-07FF => T2 Tx */ c1 = *(uchar*)(str+1) ^ Tx; if(c1 & Testx) goto bad; if(c < T3) { if(c < T2) goto bad; l = ((c << Bitx) | c1) & Rune2; if(l <= Rune1) goto bad; *rune = l; return 2; } /* * three character sequence * 0800-FFFF => T3 Tx Tx */ c2 = *(uchar*)(str+2) ^ Tx; if(c2 & Testx) goto bad; if(c < T4) { l = ((((c << Bitx) | c1) << Bitx) | c2) & Rune3; if(l <= Rune2) goto bad; *rune = l; return 3; } /* * bad decoding */ bad: *rune = Bad; return 1; } int runetochar(char *str, const Rune *rune) { long c; /* * one character sequence * 00000-0007F => 00-7F */ c = *rune; if(c <= Rune1) { str[0] = c; return 1; } /* * two character sequence * 0080-07FF => T2 Tx */ if(c <= Rune2) { str[0] = T2 | (c >> 1*Bitx); str[1] = Tx | (c & Maskx); return 2; } /* * three character sequence * 0800-FFFF => T3 Tx Tx */ str[0] = T3 | (c >> 2*Bitx); str[1] = Tx | ((c >> 1*Bitx) & Maskx); str[2] = Tx | (c & Maskx); return 3; } int runelen(long c) { Rune rune; char str[10]; rune = c; return runetochar(str, &rune); } int runenlen(const Rune *r, int nrune) { int nb, c; nb = 0; while(nrune--) { c = *r++; if(c <= Rune1) nb++; else if(c <= Rune2) nb += 2; else nb += 3; } return nb; } int fullrune(const char *str, int n) { int c; if(n > 0) { c = *(uchar*)str; if(c < Tx) return 1; if(n > 1) if(c < T3 || n > 2) return 1; } return 0; } Rune* runestrcat(Rune *s1, const Rune *s2) { runestrcpy(runestrchr(s1, 0), s2); return s1; } Rune* runestrchr(const Rune *s, Rune c) { Rune c0 = c; Rune c1; if(c == 0) { while(*s++) ; return (Rune*) s-1; } while((c1 = *s++)) if(c1 == c0) return (Rune*) s-1; return 0; } int runestrcmp(const Rune *s1, const Rune *s2) { Rune c1, c2; for(;;) { c1 = *s1++; c2 = *s2++; if(c1 != c2) { if(c1 > c2) return 1; return -1; } if(c1 == 0) return 0; } } Rune* runestrcpy(Rune *s1, const Rune *s2) { Rune *os1; os1 = s1; while((*s1++ = *s2++)) ; return os1; } Rune* runestrdup(const Rune *s) { Rune *ns; ns = malloc(sizeof(Rune)*(runestrlen(s) + 1)); if(ns == 0) return 0; return runestrcpy(ns, s); } Rune* runestrecpy(Rune *s1, Rune *es1, const Rune *s2) { if(s1 >= es1) return s1; while((*s1++ = *s2++)){ if(s1 == es1){ *--s1 = '\0'; break; } } return s1; } long runestrlen(const Rune *s) { return runestrchr(s, 0) - s; } Rune* runestrncat(Rune *s1, const Rune *s2, long n) { Rune *os1; os1 = s1; s1 = runestrchr(s1, 0); while((*s1++ = *s2++)) if(--n < 0) { s1[-1] = 0; break; } return os1; } int runestrncmp(const Rune *s1, const Rune *s2, long n) { Rune c1, c2; while(n > 0) { c1 = *s1++; c2 = *s2++; n--; if(c1 != c2) { if(c1 > c2) return 1; return -1; } if(c1 == 0) break; } return 0; } Rune* runestrncpy(Rune *s1, const Rune *s2, long n) { int i; Rune *os1; os1 = s1; for(i = 0; i < n; i++) if((*s1++ = *s2++) == 0) { while(++i < n) *s1++ = 0; return os1; } return os1; } Rune* runestrrchr(const Rune *s, Rune c) { Rune *r; if(c == 0) return runestrchr(s, 0); r = 0; while((s = runestrchr(s, c))) r = (Rune*) s++; return r; } /* * Return pointer to first occurrence of s2 in s1, * 0 if none */ Rune* runestrstr(const Rune *s1, const Rune *s2) { const Rune *p, *pa, *pb; int c0, c; c0 = *s2; if(c0 == 0) return (Rune*) s1; s2++; for(p=runestrchr(s1, c0); p; p=runestrchr(p+1, c0)) { pa = p; for(pb=s2;; pb++) { c = *pb; if(c == 0) return (Rune*) p; if(c != *++pa) break; } } return 0; } char* utfecpy(char *to, char *e, const char *from) { char *end; if(to >= e) return to; end = memccpy(to, from, '\0', e - to); if(end == 0){ end = e-1; while(end>to && (*--end&0xC0)==0x80) ; *end = '\0'; }else{ end--; } return end; } int utflen(const char *s) { int c; long n; Rune rune; n = 0; for(;;) { c = *(uchar*)s; if(c < Runeself) { if(c == 0) return n; s++; } else s += chartorune(&rune, s); n++; } } int utfnlen(const char *s, long m) { int c; long n; Rune rune; const char *es; es = s + m; for(n = 0; s < es; n++) { c = *(uchar*)s; if(c < Runeself){ if(c == '\0') break; s++; continue; } if(!fullrune(s, es-s)) break; s += chartorune(&rune, s); } return n; } char* utfrrune(const char *s, long c) { long c1; Rune r; const char *s1; if(c < Runesync) /* not part of utf sequence */ return strrchr(s, c); s1 = 0; for(;;) { c1 = *(uchar*)s; if(c1 < Runeself) { /* one byte rune */ if(c1 == 0) return (char*) s1; if(c1 == c) s1 = s; s++; continue; } c1 = chartorune(&r, s); if(r == c) s1 = s; s += c1; } } char* utfrune(const char *s, long c) { long c1; Rune r; int n; if(c < Runesync) /* not part of utf sequence */ return strchr(s, c); for(;;) { c1 = *(uchar*)s; if(c1 < Runeself) { /* one byte rune */ if(c1 == 0) return 0; if(c1 == c) return (char*) s; s++; continue; } n = chartorune(&r, s); if(r == c) return (char*) s; s += n; } } /* * Return pointer to first occurrence of s2 in s1, * 0 if none */ char* utfutf(const char *s1, const char *s2) { const char *p; long f, n1, n2; Rune r; n1 = chartorune(&r, s2); f = r; if(f <= Runesync) /* represents self */ return strstr(s1, s2); n2 = strlen(s2); for(p=s1; (p=utfrune(p, f)); p+=n1) if(strncmp(p, s2, n2) == 0) return (char*) p; return 0; }