diff options
Diffstat (limited to '')
-rw-r--r-- | exfat/libexfat/utf.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/exfat/libexfat/utf.c b/exfat/libexfat/utf.c new file mode 100644 index 000000000..983c7930b --- /dev/null +++ b/exfat/libexfat/utf.c @@ -0,0 +1,229 @@ +/* + utf.c (13.09.09) + exFAT file system implementation library. + + Copyright (C) 2010-2012 Andrew Nayenko + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "exfat.h" +#include <errno.h> + +static char* wchar_to_utf8(char* output, wchar_t wc, size_t outsize) +{ + if (wc <= 0x7f) + { + if (outsize < 1) + return NULL; + *output++ = (char) wc; + } + else if (wc <= 0x7ff) + { + if (outsize < 2) + return NULL; + *output++ = 0xc0 | (wc >> 6); + *output++ = 0x80 | (wc & 0x3f); + } + else if (wc <= 0xffff) + { + if (outsize < 3) + return NULL; + *output++ = 0xe0 | (wc >> 12); + *output++ = 0x80 | ((wc >> 6) & 0x3f); + *output++ = 0x80 | (wc & 0x3f); + } + else if (wc <= 0x1fffff) + { + if (outsize < 4) + return NULL; + *output++ = 0xf0 | (wc >> 18); + *output++ = 0x80 | ((wc >> 12) & 0x3f); + *output++ = 0x80 | ((wc >> 6) & 0x3f); + *output++ = 0x80 | (wc & 0x3f); + } + else if (wc <= 0x3ffffff) + { + if (outsize < 5) + return NULL; + *output++ = 0xf8 | (wc >> 24); + *output++ = 0x80 | ((wc >> 18) & 0x3f); + *output++ = 0x80 | ((wc >> 12) & 0x3f); + *output++ = 0x80 | ((wc >> 6) & 0x3f); + *output++ = 0x80 | (wc & 0x3f); + } + else if (wc <= 0x7fffffff) + { + if (outsize < 6) + return NULL; + *output++ = 0xfc | (wc >> 30); + *output++ = 0x80 | ((wc >> 24) & 0x3f); + *output++ = 0x80 | ((wc >> 18) & 0x3f); + *output++ = 0x80 | ((wc >> 12) & 0x3f); + *output++ = 0x80 | ((wc >> 6) & 0x3f); + *output++ = 0x80 | (wc & 0x3f); + } + else + return NULL; + + return output; +} + +static const le16_t* utf16_to_wchar(const le16_t* input, wchar_t* wc, + size_t insize) +{ + if ((le16_to_cpu(input[0]) & 0xfc00) == 0xd800) + { + if (insize < 2 || (le16_to_cpu(input[1]) & 0xfc00) != 0xdc00) + return NULL; + *wc = ((wchar_t) (le16_to_cpu(input[0]) & 0x3ff) << 10); + *wc |= (le16_to_cpu(input[1]) & 0x3ff); + *wc += 0x10000; + return input + 2; + } + else + { + *wc = le16_to_cpu(*input); + return input + 1; + } +} + +int utf16_to_utf8(char* output, const le16_t* input, size_t outsize, + size_t insize) +{ + const le16_t* inp = input; + char* outp = output; + wchar_t wc; + + while (inp - input < insize && le16_to_cpu(*inp)) + { + inp = utf16_to_wchar(inp, &wc, insize - (inp - input)); + if (inp == NULL) + { + exfat_error("illegal UTF-16 sequence"); + return -EILSEQ; + } + outp = wchar_to_utf8(outp, wc, outsize - (outp - output)); + if (outp == NULL) + { + exfat_error("name is too long"); + return -ENAMETOOLONG; + } + } + *outp = '\0'; + return 0; +} + +static const char* utf8_to_wchar(const char* input, wchar_t* wc, + size_t insize) +{ + if ((input[0] & 0x80) == 0 && insize >= 1) + { + *wc = (wchar_t) input[0]; + return input + 1; + } + if ((input[0] & 0xe0) == 0xc0 && insize >= 2) + { + *wc = (((wchar_t) input[0] & 0x1f) << 6) | + ((wchar_t) input[1] & 0x3f); + return input + 2; + } + if ((input[0] & 0xf0) == 0xe0 && insize >= 3) + { + *wc = (((wchar_t) input[0] & 0x0f) << 12) | + (((wchar_t) input[1] & 0x3f) << 6) | + ((wchar_t) input[2] & 0x3f); + return input + 3; + } + if ((input[0] & 0xf8) == 0xf0 && insize >= 4) + { + *wc = (((wchar_t) input[0] & 0x07) << 18) | + (((wchar_t) input[1] & 0x3f) << 12) | + (((wchar_t) input[2] & 0x3f) << 6) | + ((wchar_t) input[3] & 0x3f); + return input + 4; + } + if ((input[0] & 0xfc) == 0xf8 && insize >= 5) + { + *wc = (((wchar_t) input[0] & 0x03) << 24) | + (((wchar_t) input[1] & 0x3f) << 18) | + (((wchar_t) input[2] & 0x3f) << 12) | + (((wchar_t) input[3] & 0x3f) << 6) | + ((wchar_t) input[4] & 0x3f); + return input + 5; + } + if ((input[0] & 0xfe) == 0xfc && insize >= 6) + { + *wc = (((wchar_t) input[0] & 0x01) << 30) | + (((wchar_t) input[1] & 0x3f) << 24) | + (((wchar_t) input[2] & 0x3f) << 18) | + (((wchar_t) input[3] & 0x3f) << 12) | + (((wchar_t) input[4] & 0x3f) << 6) | + ((wchar_t) input[5] & 0x3f); + return input + 6; + } + return NULL; +} + +static le16_t* wchar_to_utf16(le16_t* output, wchar_t wc, size_t outsize) +{ + if (wc <= 0xffff) /* if character is from BMP */ + { + if (outsize == 0) + return NULL; + output[0] = cpu_to_le16(wc); + return output + 1; + } + if (outsize < 2) + return NULL; + wc -= 0x10000; + output[0] = cpu_to_le16(0xd800 | ((wc >> 10) & 0x3ff)); + output[1] = cpu_to_le16(0xdc00 | (wc & 0x3ff)); + return output + 2; +} + +int utf8_to_utf16(le16_t* output, const char* input, size_t outsize, + size_t insize) +{ + const char* inp = input; + le16_t* outp = output; + wchar_t wc; + + while (inp - input < insize && *inp) + { + inp = utf8_to_wchar(inp, &wc, insize - (inp - input)); + if (inp == NULL) + { + exfat_error("illegal UTF-8 sequence"); + return -EILSEQ; + } + outp = wchar_to_utf16(outp, wc, outsize - (outp - output)); + if (outp == NULL) + { + exfat_error("name is too long"); + return -ENAMETOOLONG; + } + } + *outp = cpu_to_le16(0); + return 0; +} + +size_t utf16_length(const le16_t* str) +{ + size_t i = 0; + + while (le16_to_cpu(str[i])) + i++; + return i; +} |