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Diffstat (limited to 'util/sbase/libutf/rune.c')
| -rw-r--r-- | util/sbase/libutf/rune.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/util/sbase/libutf/rune.c b/util/sbase/libutf/rune.c new file mode 100644 index 00000000..1273f451 --- /dev/null +++ b/util/sbase/libutf/rune.c @@ -0,0 +1,148 @@ +/* MIT/X Consortium Copyright (c) 2012 Connor Lane Smith <cls@lubutu.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ +#include "../utf.h" + +#define MIN(x,y) ((x) < (y) ? (x) : (y)) + +#define UTFSEQ(x) ((((x) & 0x80) == 0x00) ? 1 /* 0xxxxxxx */ \ + : (((x) & 0xC0) == 0x80) ? 0 /* 10xxxxxx */ \ + : (((x) & 0xE0) == 0xC0) ? 2 /* 110xxxxx */ \ + : (((x) & 0xF0) == 0xE0) ? 3 /* 1110xxxx */ \ + : (((x) & 0xF8) == 0xF0) ? 4 /* 11110xxx */ \ + : (((x) & 0xFC) == 0xF8) ? 5 /* 111110xx */ \ + : (((x) & 0xFE) == 0xFC) ? 6 /* 1111110x */ \ + : 0 ) + +#define BADRUNE(x) ((x) < 0 || (x) > Runemax \ + || ((x) & 0xFFFE) == 0xFFFE \ + || ((x) >= 0xD800 && (x) <= 0xDFFF) \ + || ((x) >= 0xFDD0 && (x) <= 0xFDEF)) + +int +runetochar(char *s, const Rune *p) +{ + Rune r = *p; + + switch(runelen(r)) { + case 1: /* 0aaaaaaa */ + s[0] = r; + return 1; + case 2: /* 00000aaa aabbbbbb */ + s[0] = 0xC0 | ((r & 0x0007C0) >> 6); /* 110aaaaa */ + s[1] = 0x80 | (r & 0x00003F); /* 10bbbbbb */ + return 2; + case 3: /* aaaabbbb bbcccccc */ + s[0] = 0xE0 | ((r & 0x00F000) >> 12); /* 1110aaaa */ + s[1] = 0x80 | ((r & 0x000FC0) >> 6); /* 10bbbbbb */ + s[2] = 0x80 | (r & 0x00003F); /* 10cccccc */ + return 3; + case 4: /* 000aaabb bbbbcccc ccdddddd */ + s[0] = 0xF0 | ((r & 0x1C0000) >> 18); /* 11110aaa */ + s[1] = 0x80 | ((r & 0x03F000) >> 12); /* 10bbbbbb */ + s[2] = 0x80 | ((r & 0x000FC0) >> 6); /* 10cccccc */ + s[3] = 0x80 | (r & 0x00003F); /* 10dddddd */ + return 4; + default: + return 0; /* error */ + } +} + +int +chartorune(Rune *p, const char *s) +{ + return charntorune(p, s, UTFmax); +} + +int +charntorune(Rune *p, const char *s, size_t len) +{ + unsigned int i, n; + Rune r; + + if(len == 0) /* can't even look at s[0] */ + return 0; + + switch((n = UTFSEQ(s[0]))) { + case 1: r = s[0]; break; /* 0xxxxxxx */ + case 2: r = s[0] & 0x1F; break; /* 110xxxxx */ + case 3: r = s[0] & 0x0F; break; /* 1110xxxx */ + case 4: r = s[0] & 0x07; break; /* 11110xxx */ + case 5: r = s[0] & 0x03; break; /* 111110xx */ + case 6: r = s[0] & 0x01; break; /* 1111110x */ + default: /* invalid sequence */ + *p = Runeerror; + return 1; + } + /* add values from continuation bytes */ + for(i = 1; i < MIN(n, len); i++) + if((s[i] & 0xC0) == 0x80) { + /* add bits from continuation byte to rune value + * cannot overflow: 6 byte sequences contain 31 bits */ + r = (r << 6) | (s[i] & 0x3F); /* 10xxxxxx */ + } + else { /* expected continuation */ + *p = Runeerror; + return i; + } + + if(i < n) /* must have reached len limit */ + return 0; + + /* reject invalid or overlong sequences */ + if(BADRUNE(r) || runelen(r) < (int)n) + r = Runeerror; + + *p = r; + return n; +} + +int +runelen(Rune r) +{ + if(BADRUNE(r)) + return 0; /* error */ + else if(r <= 0x7F) + return 1; + else if(r <= 0x07FF) + return 2; + else if(r <= 0xFFFF) + return 3; + else + return 4; +} + +size_t +runenlen(const Rune *p, size_t len) +{ + size_t i, n = 0; + + for(i = 0; i < len; i++) + n += runelen(p[i]); + return n; +} + +int +fullrune(const char *s, size_t len) +{ + Rune r; + + return charntorune(&r, s, len) > 0; +} |