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e16a7d8f3b
`et` means `expandtab`. ```sh rg 'vi: .* :vi' -l -0 | \ xargs -0 sed -i '' 's/vi: \(.*\) et\(.*\) :vi/vi: \1 xoet\2:vi/' rg 'vi: .* :vi' -l -0 | \ xargs -0 sed -i '' 's/vi: \(.*\)noet\(.*\):vi/vi: \1et\2 :vi/' rg 'vi: .* :vi' -l -0 | \ xargs -0 sed -i '' 's/vi: \(.*\)xoet\(.*\):vi/vi: \1noet\2:vi/' ```
57 lines
2.8 KiB
C
57 lines
2.8 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2020 Justine Alexandra Roberts Tunney │
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│ │
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│ Permission to use, copy, modify, and/or distribute this software for │
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│ any purpose with or without fee is hereby granted, provided that the │
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│ above copyright notice and this permission notice appear in all copies. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
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│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
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│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
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│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
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│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
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│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
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│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
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│ PERFORMANCE OF THIS SOFTWARE. │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/str/str.h"
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/**
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* Copies at most N bytes from SRC to DST until 𝑐 is encountered.
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*
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* This is little-known C Standard Library approach, dating back to the
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* Fourth Edition of System Five, for copying a C strings to fixed-width
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* buffers, with added generality.
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*
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* For example, strictly:
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*
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* char buf[16];
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* CHECK_NOTNULL(memccpy(buf, s, '\0', sizeof(buf)));
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*
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* Or unstrictly:
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*
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* if (!memccpy(buf, s, '\0', sizeof(buf))) strcpy(buf, "?");
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*
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* Are usually more sensible than the following:
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*
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* char cstrbuf[16];
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* snprintf(cstrbuf, sizeof(cstrbuf), "%s", CSTR);
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*
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* @param c is search character and is masked with 255
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* @return DST + idx(c) + 1, or NULL if 𝑐 ∉ 𝑠₀․․ₙ₋₁
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* @note DST and SRC can't overlap
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* @asyncsignalsafe
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*/
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void *memccpy(void *dst, const void *src, int c, size_t n) {
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char *d;
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size_t i;
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const char *s;
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for (d = dst, s = src, i = 0; i < n; ++i) {
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if (((d[i] = s[i]) & 255) == (c & 255)) {
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return d + i + 1;
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}
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}
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return 0;
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}
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