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author | 2016-02-20 09:32:40 -0800 | |
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committer | 2016-02-20 09:32:40 -0800 | |
commit | 0389075ecfb6231818de9b0225d3a5a21a661171 (patch) | |
tree | 991154188efee4117974d9aa5bcd7497257c7656 /lib/ucs2_string.c | |
parent | Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff) | |
parent | x86/mm: Fix vmalloc_fault() to handle large pages properly (diff) | |
download | linux-dev-0389075ecfb6231818de9b0225d3a5a21a661171.tar.xz linux-dev-0389075ecfb6231818de9b0225d3a5a21a661171.zip |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"This is unusually large, partly due to the EFI fixes that prevent
accidental deletion of EFI variables through efivarfs that may brick
machines. These fixes are somewhat involved to maintain compatibility
with existing install methods and other usage modes, while trying to
turn off the 'rm -rf' bricking vector.
Other fixes are for large page ioremap()s and for non-temporal
user-memcpy()s"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix vmalloc_fault() to handle large pages properly
hpet: Drop stale URLs
x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
lib/ucs2_string: Correct ucs2 -> utf8 conversion
efi: Add pstore variables to the deletion whitelist
efi: Make efivarfs entries immutable by default
efi: Make our variable validation list include the guid
efi: Do variable name validation tests in utf8
efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
lib/ucs2_string: Add ucs2 -> utf8 helper functions
Diffstat (limited to 'lib/ucs2_string.c')
-rw-r--r-- | lib/ucs2_string.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/lib/ucs2_string.c b/lib/ucs2_string.c index 6f500ef2301d..f0b323abb4c6 100644 --- a/lib/ucs2_string.c +++ b/lib/ucs2_string.c @@ -49,3 +49,65 @@ ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len) } } EXPORT_SYMBOL(ucs2_strncmp); + +unsigned long +ucs2_utf8size(const ucs2_char_t *src) +{ + unsigned long i; + unsigned long j = 0; + + for (i = 0; i < ucs2_strlen(src); i++) { + u16 c = src[i]; + + if (c >= 0x800) + j += 3; + else if (c >= 0x80) + j += 2; + else + j += 1; + } + + return j; +} +EXPORT_SYMBOL(ucs2_utf8size); + +/* + * copy at most maxlength bytes of whole utf8 characters to dest from the + * ucs2 string src. + * + * The return value is the number of characters copied, not including the + * final NUL character. + */ +unsigned long +ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength) +{ + unsigned int i; + unsigned long j = 0; + unsigned long limit = ucs2_strnlen(src, maxlength); + + for (i = 0; maxlength && i < limit; i++) { + u16 c = src[i]; + + if (c >= 0x800) { + if (maxlength < 3) + break; + maxlength -= 3; + dest[j++] = 0xe0 | (c & 0xf000) >> 12; + dest[j++] = 0x80 | (c & 0x0fc0) >> 6; + dest[j++] = 0x80 | (c & 0x003f); + } else if (c >= 0x80) { + if (maxlength < 2) + break; + maxlength -= 2; + dest[j++] = 0xc0 | (c & 0x7c0) >> 6; + dest[j++] = 0x80 | (c & 0x03f); + } else { + maxlength -= 1; + dest[j++] = c & 0x7f; + } + } + if (maxlength) + dest[j] = '\0'; + return j; +} +EXPORT_SYMBOL(ucs2_as_utf8); |