1 //===-- sanitizer_procmaps_linux.cc ---------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Information about the process mappings (Linux-specific parts).
11 //===----------------------------------------------------------------------===//
12 
13 #include "sanitizer_platform.h"
14 #if SANITIZER_LINUX
15 #include "sanitizer_common.h"
16 #include "sanitizer_procmaps.h"
17 
18 namespace __sanitizer {
19 
ReadProcMaps(ProcSelfMapsBuff * proc_maps)20 void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {
21   CHECK(ReadFileToBuffer("/proc/self/maps", &proc_maps->data,
22                          &proc_maps->mmaped_size, &proc_maps->len));
23 }
24 
IsOneOf(char c,char c1,char c2)25 static bool IsOneOf(char c, char c1, char c2) {
26   return c == c1 || c == c2;
27 }
28 
Next(uptr * start,uptr * end,uptr * offset,char filename[],uptr filename_size,uptr * protection)29 bool MemoryMappingLayout::Next(uptr *start, uptr *end, uptr *offset,
30                                char filename[], uptr filename_size,
31                                uptr *protection) {
32   char *last = proc_self_maps_.data + proc_self_maps_.len;
33   if (current_ >= last) return false;
34   uptr dummy;
35   if (!start) start = &dummy;
36   if (!end) end = &dummy;
37   if (!offset) offset = &dummy;
38   if (!protection) protection = &dummy;
39   char *next_line = (char*)internal_memchr(current_, '\n', last - current_);
40   if (next_line == 0)
41     next_line = last;
42   // Example: 08048000-08056000 r-xp 00000000 03:0c 64593   /foo/bar
43   *start = ParseHex(&current_);
44   CHECK_EQ(*current_++, '-');
45   *end = ParseHex(&current_);
46   CHECK_EQ(*current_++, ' ');
47   CHECK(IsOneOf(*current_, '-', 'r'));
48   *protection = 0;
49   if (*current_++ == 'r')
50     *protection |= kProtectionRead;
51   CHECK(IsOneOf(*current_, '-', 'w'));
52   if (*current_++ == 'w')
53     *protection |= kProtectionWrite;
54   CHECK(IsOneOf(*current_, '-', 'x'));
55   if (*current_++ == 'x')
56     *protection |= kProtectionExecute;
57   CHECK(IsOneOf(*current_, 's', 'p'));
58   if (*current_++ == 's')
59     *protection |= kProtectionShared;
60   CHECK_EQ(*current_++, ' ');
61   *offset = ParseHex(&current_);
62   CHECK_EQ(*current_++, ' ');
63   ParseHex(&current_);
64   CHECK_EQ(*current_++, ':');
65   ParseHex(&current_);
66   CHECK_EQ(*current_++, ' ');
67   while (IsDecimal(*current_))
68     current_++;
69   // Qemu may lack the trailing space.
70   // https://github.com/google/sanitizers/issues/160
71   // CHECK_EQ(*current_++, ' ');
72   // Skip spaces.
73   while (current_ < next_line && *current_ == ' ')
74     current_++;
75   // Fill in the filename.
76   uptr i = 0;
77   while (current_ < next_line) {
78     if (filename && i < filename_size - 1)
79       filename[i++] = *current_;
80     current_++;
81   }
82   if (filename && i < filename_size)
83     filename[i] = 0;
84   current_ = next_line + 1;
85   return true;
86 }
87 
88 }  // namespace __sanitizer
89 
90 #endif  // SANITIZER_LINUX
91