a1c1b55e11
Add strnlen() to the string overrides to allow it to be called in the guest. The implementation for strnlen() was taken from the kernel's generic version, lib/string.c. This will be needed when printf() is introduced. Signed-off-by: Aaron Lewis <aaronlewis@google.com> Link: https://lore.kernel.org/r/20230729003643.1053367-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
48 lines
950 B
C
48 lines
950 B
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <stddef.h>
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/*
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* Override the "basic" built-in string helpers so that they can be used in
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* guest code. KVM selftests don't support dynamic loading in guest code and
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* will jump into the weeds if the compiler decides to insert an out-of-line
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* call via the PLT.
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*/
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int memcmp(const void *cs, const void *ct, size_t count)
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{
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const unsigned char *su1, *su2;
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int res = 0;
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for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--) {
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if ((res = *su1 - *su2) != 0)
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break;
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}
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return res;
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}
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void *memcpy(void *dest, const void *src, size_t count)
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{
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char *tmp = dest;
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const char *s = src;
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while (count--)
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*tmp++ = *s++;
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return dest;
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}
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void *memset(void *s, int c, size_t count)
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{
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char *xs = s;
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while (count--)
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*xs++ = c;
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return s;
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}
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size_t strnlen(const char *s, size_t count)
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{
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const char *sc;
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for (sc = s; count-- && *sc != '\0'; ++sc)
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/* nothing */;
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return sc - s;
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}
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