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3aaa63eb46
value < 0. errno is only updated in this case. Change all (most?) callers of syscalls to follow this better, and let's see if this strictness helps us in the future.
96 lines
2.5 KiB
C
96 lines
2.5 KiB
C
/*
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* $OpenBSD: readlink.c,v 1.28 2019/06/28 13:35:03 deraadt Exp $
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*
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* Copyright (c) 1997
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* Kenneth Stailey (hereinafter referred to as the author)
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <err.h>
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#include <errno.h>
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#include <limits.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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static void usage(void);
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int
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main(int argc, char *argv[])
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{
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char buf[PATH_MAX];
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int n, ch, nflag = 0, fflag = 0;
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extern int optind;
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if (pledge("stdio rpath", NULL) == -1)
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err(1, "pledge");
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while ((ch = getopt(argc, argv, "fn")) != -1)
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switch (ch) {
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case 'f':
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fflag = 1;
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break;
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case 'n':
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nflag = 1;
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break;
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default:
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usage();
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}
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argc -= optind;
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argv += optind;
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if (argc != 1)
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usage();
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n = strlen(argv[0]);
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if (n > PATH_MAX - 1) {
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fprintf(stderr,
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"readlink: filename longer than PATH_MAX-1 (%d)\n",
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PATH_MAX - 1);
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exit(1);
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}
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if (fflag) {
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if (realpath(argv[0], buf) == NULL)
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err(1, "%s", argv[0]);
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} else {
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if ((n = readlink(argv[0], buf, sizeof buf-1)) == -1)
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exit(1);
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buf[n] = '\0';
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}
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printf("%s", buf);
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if (!nflag)
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putchar('\n');
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exit(0);
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}
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static void
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usage(void)
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{
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(void)fprintf(stderr, "usage: readlink [-fn] file\n");
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exit(1);
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}
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