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/*
* Copyright (c) 2013, The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google, Inc. nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
static int skip_newline, quiet_errors, canonicalize;
static void usage(char* name) {
fprintf(stderr, "Usage: %s [OPTION]... FILE\n", name);
}
int readlink_main(int argc, char* argv[]) {
int c;
while ((c = getopt(argc, argv, "nfqs")) != -1) {
switch (c) {
case 'n':
skip_newline = 1;
break;
case 'f':
canonicalize = 1;
break;
case 'q':
case 's':
quiet_errors = 1;
break;
case '?':
default:
usage(argv[0]);
return EXIT_FAILURE;
}
}
int index = optind;
if (argc - index != 1) {
usage(argv[0]);
return EXIT_FAILURE;
}
char name[PATH_MAX+1];
if (canonicalize) {
if(!realpath(argv[optind], name)) {
if (!quiet_errors) {
perror("readlink");
}
return EXIT_FAILURE;
}
} else {
ssize_t len = readlink(argv[1], name, PATH_MAX);
if (len < 0) {
if (!quiet_errors) {
perror("readlink");
}
return EXIT_FAILURE;
}
name[len] = '\0';
}
fputs(name, stdout);
if (!skip_newline) {
fputs("\n", stdout);
}
return EXIT_SUCCESS;
}
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