Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
lib/ucs2_string: Add UCS-2 strscpy function
Add a ucs2_strscpy() function for UCS-2 strings. The behavior is
equivalent to the standard strscpy() function, just for 16-bit character
UCS-2 strings.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230827211408.689076-2-luzmaximilian@gmail.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
authored by
Maximilian Luz
and committed by
Bjorn Andersson
e4c89f93
0bb80ecc
+53
+1
include/linux/ucs2_string.h
+1
include/linux/ucs2_string.h
···
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unsigned long ucs2_strnlen(const ucs2_char_t *s, size_t maxlength);
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unsigned long ucs2_strlen(const ucs2_char_t *s);
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unsigned long ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength);
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ssize_t ucs2_strscpy(ucs2_char_t *dst, const ucs2_char_t *src, size_t count);
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int ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len);
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unsigned long ucs2_utf8size(const ucs2_char_t *src);
+52
lib/ucs2_string.c
+52
lib/ucs2_string.c
···
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}
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EXPORT_SYMBOL(ucs2_strsize);
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/**
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* ucs2_strscpy() - Copy a UCS2 string into a sized buffer.
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*
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* @dst: Pointer to the destination buffer where to copy the string to.
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* @src: Pointer to the source buffer where to copy the string from.
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* @count: Size of the destination buffer, in UCS2 (16-bit) characters.
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*
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* Like strscpy(), only for UCS2 strings.
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*
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* Copy the source string @src, or as much of it as fits, into the destination
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* buffer @dst. The behavior is undefined if the string buffers overlap. The
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* destination buffer @dst is always NUL-terminated, unless it's zero-sized.
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*
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* Return: The number of characters copied into @dst (excluding the trailing
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* %NUL terminator) or -E2BIG if @count is 0 or @src was truncated due to the
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* destination buffer being too small.
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*/
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ssize_t ucs2_strscpy(ucs2_char_t *dst, const ucs2_char_t *src, size_t count)
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{
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long res;
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/*
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* Ensure that we have a valid amount of space. We need to store at
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* least one NUL-character.
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*/
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if (count == 0 || WARN_ON_ONCE(count > INT_MAX / sizeof(*dst)))
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return -E2BIG;
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/*
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* Copy at most 'count' characters, return early if we find a
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* NUL-terminator.
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*/
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for (res = 0; res < count; res++) {
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ucs2_char_t c;
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c = src[res];
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dst[res] = c;
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if (!c)
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return res;
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}
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/*
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* The loop above terminated without finding a NUL-terminator,
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* exceeding the 'count': Enforce proper NUL-termination and return
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* error.
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*/
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dst[count - 1] = 0;
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return -E2BIG;
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}
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EXPORT_SYMBOL(ucs2_strscpy);
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int
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ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len)
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{