diff options
Diffstat (limited to 'code/fe310/eos/unicode.c')
| -rw-r--r-- | code/fe310/eos/unicode.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/code/fe310/eos/unicode.c b/code/fe310/eos/unicode.c new file mode 100644 index 0000000..2915791 --- /dev/null +++ b/code/fe310/eos/unicode.c @@ -0,0 +1,180 @@ +#include "unicode.h" + +int utf8_enc(utf32_t ch, utf8_t *str) { + if (ch <= 0x7f) { + str[0] = ch; + return 1; + } else if (ch <= 0x7ff) { + str[0] = 0xc0 | (ch >> 6); + str[1] = 0x80 | (ch & 0x3f); + return 2; + } else if (ch <= 0xffff) { + if ((ch >= 0xd800) && (ch <= 0xdfff)) return UTF_ERR; + str[0] = 0xe0 | (ch >> 12); + str[1] = 0x80 | ((ch >> 6) & 0x3f); + str[2] = 0x80 | (ch & 0x3f); + return 3; + } else if (ch <= 0x10ffff) { + str[0] = 0xf0 | (ch >> 18); + str[1] = 0x80 | ((ch >> 12) & 0x3f); + str[2] = 0x80 | ((ch >> 6) & 0x3f); + str[3] = 0x80 | (ch & 0x3f); + return 4; + } else { + return UTF_ERR; + } +} + +int utf8_dec(utf8_t *str, utf32_t *ch) { + if ((str[0] & 0x80) == 0x00) { + *ch = str[0]; + return 1; + } else if ((str[0] & 0xe0) == 0xc0) { + if ((str[1] & 0xc0) != 0x80) return UTF_ERR; + *ch = (utf32_t)(str[0] & 0x1f) << 6; + *ch |= (utf32_t)(str[1] & 0x3f); + if (*ch < 0x80) return UTF_ERR; + return 2; + } else if ((str[0] & 0xf0) == 0xe0) { + if (((str[1] & 0xc0) != 0x80) || ((str[2] & 0xc0) != 0x80)) return UTF_ERR; + *ch = (utf32_t)(str[0] & 0x0f) << 12; + *ch |= (utf32_t)(str[1] & 0x3f) << 6; + *ch |= (utf32_t)(str[2] & 0x3f); + if ((*ch >= 0xd800) && (*ch <= 0xdfff)) return UTF_ERR; + if (*ch < 0x800) return UTF_ERR; + return 3; + } else if ((str[0] & 0xf8) == 0xf0) { + if (((str[1] & 0xc0) != 0x80) || ((str[2] & 0xc0) != 0x80) || ((str[3] & 0xc0) != 0x80)) return UTF_ERR; + *ch = (utf32_t)(str[0] & 0x07) << 18; + *ch |= (utf32_t)(str[1] & 0x0f) << 12; + *ch |= (utf32_t)(str[2] & 0x3f) << 6; + *ch |= (utf32_t)(str[3] & 0x3f); + if (*ch < 0x010000) return UTF_ERR; + if (*ch > 0x10ffff) return UTF_ERR; + return 4; + } else { + return UTF_ERR; + } +} + +int utf8_seek(utf8_t *str, int off, utf32_t *ch) { + int i; + int len = 0; + + if (off < 0) { + off = -off; + for (i=0; i<off; i++) { + len--; + while ((str[len] & 0xc0) == 0x80) len--; + } + } else { + for (i=0; i<off; i++) { + if ((str[len] & 0x80) == 0x00) { + len += 1; + } else if ((str[0] & 0xe0) == 0xc0) { + len += 2; + } else if ((str[0] & 0xf0) == 0xe0) { + len += 3; + } else if ((str[0] & 0xf8) == 0xf0) { + len += 4; + } + } + } + utf8_dec(str + len, ch); + return len; +} + +int utf8_verify(utf8_t *str, int str_size, int *str_len) { + utf32_t ch; + uint8_t ch_l; + int len = 0; + + while (len < str_size) { + if (str_size - len < 4) { + if (((str[len] & 0xf8) == 0xf0) || + (((str[len] & 0xf0) == 0xe0) && (str_size - len < 3)) || + (((str[len] & 0xe0) == 0xc0) && (str_size - len < 2))) { + break; + } + } + ch_l = utf8_dec(str + len, &ch); + if (ch_l > 0) { + if (ch == 0) { + *str_len = len; + return UTF_OK; + } + len += ch_l; + } else { + break; + } + } + *str_len = len; + return UTF_ERR; +} + +int utf16_enc(utf32_t ch, uint8_t *str) { + if (ch <= 0xffff) { + if ((ch >= 0xd800) && (ch <= 0xdfff)) return UTF_ERR; + str[0] = ch >> 8; + str[1] = ch & 0xff; + return 2; + } else if (ch <= 0x10ffff) { + uint16_t hi; + uint16_t lo; + + ch -= 0x10000; + hi = (ch >> 10) + 0xd800; + lo = (ch & 0x3ff) + 0xdc00; + str[0] = hi >> 8; + str[1] = hi & 0xff; + str[2] = lo >> 8; + str[3] = lo & 0xff; + return 4; + } else { + return UTF_ERR; + } +} + +int utf16_dec(uint8_t *str, utf32_t *ch) { + *ch = (str[0] << 8) | str[1]; + if ((*ch >= 0xd800) && (*ch <= 0xdfff)) { + uint16_t hi = *ch; + uint16_t lo; + + if (hi > 0xdbff) return UTF_ERR; + lo = (str[2] << 8) | str[3]; + if ((lo < 0xdc00) || (lo > 0xdfff)) return UTF_ERR; + *ch = (((hi - 0xd800) << 10) | (lo - 0xdc00)) + 0x10000; + return 4; + } else { + return 2; + } +} + +int utf16_seek(uint8_t *str, int off, utf32_t *ch) { + int i; + int len = 0; + uint16_t cu; + + if (off < 0) { + off = -off; + for (i=0; i<off; i++) { + len -= 2; + cu = (str[len] << 8) | str[len + 1]; + if ((cu >= 0xdc00) && (cu <= 0xdfff)) { + len -= 2; + } + } + } else { + for (i=0; i<off; i++) { + cu = (str[len] << 8) | str[len + 1]; + if ((cu >= 0xd800) && (cu <= 0xdbff)) { + len += 4; + } else { + len += 2; + } + } + } + utf16_dec(str + len, ch); + return len; +} |