1 // Copyright 2013 Google LLC
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #ifndef __STDC_FORMAT_MACROS
6 #define __STDC_FORMAT_MACROS
7 #endif
8
9 #ifdef HAVE_CONFIG_H
10 #include <config.h> // Must come first
11 #endif
12
13 #include "google_breakpad/processor/proc_maps_linux.h"
14
15 #include <fcntl.h>
16 #include <inttypes.h>
17 #include <stdio.h>
18
19 #include "common/using_std_string.h"
20 #include "processor/logging.h"
21
22 #if defined(OS_ANDROID) && !defined(__LP64__)
23 // In 32-bit mode, Bionic's inttypes.h defines PRI/SCNxPTR as an
24 // unsigned long int, which is incompatible with Bionic's stdint.h
25 // defining uintptr_t as an unsigned int:
26 // https://code.google.com/p/android/issues/detail?id=57218
27 #undef SCNxPTR
28 #define SCNxPTR "x"
29 #endif
30
31 namespace google_breakpad {
32
ParseProcMaps(const string & input,std::vector<MappedMemoryRegion> * regions_out)33 bool ParseProcMaps(const string& input,
34 std::vector<MappedMemoryRegion>* regions_out) {
35 std::vector<MappedMemoryRegion> regions;
36
37 // This isn't async safe nor terribly efficient, but it doesn't need to be at
38 // this point in time.
39
40 // Split the string by newlines.
41 std::vector<string> lines;
42 string l = "";
43 for (size_t i = 0; i < input.size(); i++) {
44 if (input[i] != '\n' && input[i] != '\r') {
45 l.push_back(input[i]);
46 } else if (l.size() > 0) {
47 lines.push_back(l);
48 l.clear();
49 }
50 }
51 if (l.size() > 0) {
52 BPLOG(ERROR) << "Input doesn't end in newline";
53 return false;
54 }
55
56 for (size_t i = 0; i < lines.size(); ++i) {
57 MappedMemoryRegion region;
58 const char* line = lines[i].c_str();
59 char permissions[5] = {'\0'}; // Ensure NUL-terminated string.
60 int path_index = 0;
61
62 // Sample format from man 5 proc:
63 //
64 // address perms offset dev inode pathname
65 // 08048000-08056000 r-xp 00000000 03:0c 64593 /usr/sbin/gpm
66 //
67 // The final %n term captures the offset in the input string, which is used
68 // to determine the path name. It *does not* increment the return value.
69 // Refer to man 3 sscanf for details.
70 if (sscanf(line, "%" SCNx64 "-%" SCNx64 " %4c %" SCNx64" %hhx:%hhx %"
71 SCNd64 " %n", ®ion.start, ®ion.end, permissions,
72 ®ion.offset, ®ion.major_device, ®ion.minor_device,
73 ®ion.inode, &path_index) < 7) {
74 BPLOG(ERROR) << "sscanf failed for line: " << line;
75 return false;
76 }
77
78 region.permissions = 0;
79
80 if (permissions[0] == 'r')
81 region.permissions |= MappedMemoryRegion::READ;
82 else if (permissions[0] != '-')
83 return false;
84
85 if (permissions[1] == 'w')
86 region.permissions |= MappedMemoryRegion::WRITE;
87 else if (permissions[1] != '-')
88 return false;
89
90 if (permissions[2] == 'x')
91 region.permissions |= MappedMemoryRegion::EXECUTE;
92 else if (permissions[2] != '-')
93 return false;
94
95 if (permissions[3] == 'p')
96 region.permissions |= MappedMemoryRegion::PRIVATE;
97 else if (permissions[3] != 's' && permissions[3] != 'S') // Shared memory.
98 return false;
99
100 // Pushing then assigning saves us a string copy.
101 regions.push_back(region);
102 regions.back().path.assign(line + path_index);
103 regions.back().line.assign(line);
104 }
105
106 regions_out->swap(regions);
107 return true;
108 }
109
110 } // namespace google_breakpad
111