1 | // Copyright (c) 2011, Google Inc. |
2 | // All rights reserved. |
3 | // |
4 | // Redistribution and use in source and binary forms, with or without |
5 | // modification, are permitted provided that the following conditions are |
6 | // met: |
7 | // |
8 | // * Redistributions of source code must retain the above copyright |
9 | // notice, this list of conditions and the following disclaimer. |
10 | // * Redistributions in binary form must reproduce the above |
11 | // copyright notice, this list of conditions and the following disclaimer |
12 | // in the documentation and/or other materials provided with the |
13 | // distribution. |
14 | // * Neither the name of Google Inc. nor the names of its |
15 | // contributors may be used to endorse or promote products derived from |
16 | // this software without specific prior written permission. |
17 | // |
18 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
19 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
20 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
21 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
22 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
23 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
24 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
25 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
26 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
27 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
28 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
29 | |
30 | // safe_readlink.cc: Implement google_breakpad::SafeReadLink. |
31 | // See safe_readlink.h for details. |
32 | |
33 | #include <stddef.h> |
34 | |
35 | #include "third_party/lss/linux_syscall_support.h" |
36 | |
37 | namespace google_breakpad { |
38 | |
39 | bool SafeReadLink(const char* path, char* buffer, size_t buffer_size) { |
40 | // sys_readlink() does not add a NULL byte to |buffer|. In order to return |
41 | // a NULL-terminated string in |buffer|, |buffer_size| should be at least |
42 | // one byte longer than the expected path length. Also, sys_readlink() |
43 | // returns the actual path length on success, which does not count the |
44 | // NULL byte, so |result_size| should be less than |buffer_size|. |
45 | ssize_t result_size = sys_readlink(path, buffer, buffer_size); |
46 | if (result_size >= 0 && static_cast<size_t>(result_size) < buffer_size) { |
47 | buffer[result_size] = '\0'; |
48 | return true; |
49 | } |
50 | return false; |
51 | } |
52 | |
53 | } // namespace google_breakpad |
54 | |