1 /*
2 * Copyright © 2019 Red Hat, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24 #include <config.h>
25
26 #pragma once
27
28 #include <unistd.h>
29 #include "util-strings.h"
30
31 /**
32 * Try to figure out the directory we're executing from and if it matches
33 * the builddir, return that directory. Otherwise, return NULL.
34 */
35 static inline char *
builddir_lookup(void)36 builddir_lookup(void)
37 {
38 char execdir[PATH_MAX];
39 char *pathsep;
40 ssize_t nread;
41
42 /* In the case of release builds, the builddir is
43 the empty string */
44 if (streq(MESON_BUILD_ROOT, ""))
45 return NULL;
46
47 nread = readlink("/proc/self/exe", execdir, sizeof(execdir) - 1);
48 if (nread <= 0 || nread == sizeof(execdir) - 1)
49 return NULL;
50
51 /* readlink doesn't terminate the string and readlink says
52 anything past sz is undefined */
53 execdir[nread] = '\0';
54
55 pathsep = strrchr(execdir, '/');
56 if (!pathsep)
57 return NULL;
58
59 *pathsep = '\0';
60 if (!streq(execdir, MESON_BUILD_ROOT))
61 return NULL;
62
63 return safe_strdup(execdir);
64 }
65