1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/MemoryMapping.h"
#include "mozilla/BinarySearch.h"
#include "mozilla/FileUtils.h"
#include <fstream>
#include <string>
#include <sstream>
namespace mozilla {
namespace {
struct VMFlagString {
const char* mName;
const char* mPrettyName;
VMFlag mFlag;
};
static const VMFlagString sVMFlagStrings[] = {
// clang-format off
{"ac", "Accountable", VMFlag::Accountable},
{"ar", "ArchSpecific", VMFlag::ArchSpecific},
{"dc", "NoFork", VMFlag::NoFork},
{"dd", "NoCore", VMFlag::NoCore},
{"de", "NoExpand", VMFlag::NoExpand},
{"dw", "DisabledWrite", VMFlag::DisabledWrite},
{"ex", "Executable", VMFlag::Executable},
{"gd", "GrowsDown", VMFlag::GrowsDown},
{"hg", "HugePage", VMFlag::HugePage},
{"ht", "HugeTLB", VMFlag::HugeTLB},
{"io", "IO", VMFlag::IO},
{"lo", "Locked", VMFlag::Locked},
{"me", "MayExecute", VMFlag::MayExecute},
{"mg", "Mergeable", VMFlag::Mergeable},
{"mm", "MixedMap", VMFlag::MixedMap},
{"mr", "MayRead", VMFlag::MayRead},
{"ms", "MayShare", VMFlag::MayShare},
{"mw", "MayWrite", VMFlag::MayWrite},
{"nh", "NoHugePage", VMFlag::NoHugePage},
{"nl", "NonLinear", VMFlag::NonLinear},
{"nr", "NotReserved", VMFlag::NotReserved},
{"pf", "PurePFN", VMFlag::PurePFN},
{"rd", "Readable", VMFlag::Readable},
{"rr", "Random", VMFlag::Random},
{"sd", "SoftDirty", VMFlag::SoftDirty},
{"sh", "Shared", VMFlag::Shared},
{"sr", "Sequential", VMFlag::Sequential},
{"wr", "Writable", VMFlag::Writable},
// clang-format on
};
} // anonymous namespace
constexpr size_t kVMFlags = size_t(-1);
// An array of known field names which may be present in an smaps file, and the
// offsets of the corresponding fields in a MemoryMapping class.
const MemoryMapping::Field MemoryMapping::sFields[] = {
// clang-format off
{"AnonHugePages", offsetof(MemoryMapping, mAnonHugePages)},
{"Anonymous", offsetof(MemoryMapping, mAnonymous)},
{"KernelPageSize", offsetof(MemoryMapping, mKernelPageSize)},
{"LazyFree", offsetof(MemoryMapping, mLazyFree)},
{"Locked", offsetof(MemoryMapping, mLocked)},
{"MMUPageSize", offsetof(MemoryMapping, mMMUPageSize)},
{"Private_Clean", offsetof(MemoryMapping, mPrivate_Clean)},
{"Private_Dirty", offsetof(MemoryMapping, mPrivate_Dirty)},
{"Private_Hugetlb", offsetof(MemoryMapping, mPrivate_Hugetlb)},
{"Pss", offsetof(MemoryMapping, mPss)},
{"Referenced", offsetof(MemoryMapping, mReferenced)},
{"Rss", offsetof(MemoryMapping, mRss)},
{"Shared_Clean", offsetof(MemoryMapping, mShared_Clean)},
{"Shared_Dirty", offsetof(MemoryMapping, mShared_Dirty)},
{"Shared_Hugetlb", offsetof(MemoryMapping, mShared_Hugetlb)},
{"ShmemPmdMapped", offsetof(MemoryMapping, mShmemPmdMapped)},
{"Size", offsetof(MemoryMapping, mSize)},
{"Swap", offsetof(MemoryMapping, mSwap)},
{"SwapPss", offsetof(MemoryMapping, mSwapPss)},
// VmFlags is a special case. It contains an array of flag strings, which
// describe attributes of the mapping, rather than a mapping size. We include
// it in this array to aid in parsing, but give it a separate sentinel value,
// and treat it specially.
{"VmFlags", kVMFlags},
// clang-format on
};
template <typename T, int n>
const T* FindEntry(const char* aName, const T (&aEntries)[n]) {
size_t index;
if (BinarySearchIf(
aEntries, 0, n,
[&](const T& aEntry) { return strcmp(aName, aEntry.mName); },
&index)) {
return &aEntries[index];
}
return nullptr;
}
using Perm = MemoryMapping::Perm;
using PermSet = MemoryMapping::PermSet;
nsresult GetMemoryMappings(nsTArray<MemoryMapping>& aMappings, pid_t aPid) {
std::ifstream stream;
if (aPid == 0) {
stream.open("/proc/self/smaps");
} else {
std::ostringstream path;
path << "/proc/" << aPid << "/smaps" << std::ends;
stream.open(path.str());
}
if (stream.fail()) {
return NS_ERROR_FAILURE;
}
MemoryMapping* current = nullptr;
std::string buffer;
while (std::getline(stream, buffer)) {
size_t start, end, offset;
char flags[4] = "---";
char name[512];
name[0] = 0;
// clang-format off
// Match the start of an entry. A typical line looks something like:
//
// 1487118a7000-148711a5a000 r-xp 00000000 103:03 54004561 /usr/lib/libc-2.27.so
// clang-format on
if (sscanf(buffer.c_str(), "%zx-%zx %4c %zx %*u:%*u %*u %511s\n", &start,
&end, flags, &offset, name) >= 4) {
PermSet perms;
if (flags[0] == 'r') {
perms += Perm::Read;
}
if (flags[1] == 'w') {
perms += Perm::Write;
}
if (flags[2] == 'x') {
perms += Perm::Execute;
}
if (flags[3] == 'p') {
perms += Perm::Private;
} else if (flags[3] == 's') {
perms += Perm::Shared;
}
current = aMappings.AppendElement(
MemoryMapping{start, end, perms, offset, name});
continue;
}
if (!current) {
continue;
}
nsAutoCStringN<128> line(buffer.c_str());
char* savePtr;
char* fieldName = strtok_r(line.BeginWriting(), ":", &savePtr);
if (!fieldName) {
continue;
}
auto* field = FindEntry(fieldName, MemoryMapping::sFields);
if (!field) {
continue;
}
if (field->mOffset == kVMFlags) {
while (char* flagName = strtok_r(nullptr, " \n", &savePtr)) {
if (auto* flag = FindEntry(flagName, sVMFlagStrings)) {
current->mFlags += flag->mFlag;
}
}
continue;
}
const char* rest = strtok_r(nullptr, "\n", &savePtr);
size_t value;
if (sscanf(rest, "%zd kB", &value) > 0) {
current->ValueForField(*field) = value * 1024;
}
}
return NS_OK;
}
void MemoryMapping::Dump(nsACString& aOut) const {
aOut.AppendPrintf("%zx-%zx Size: %zu Offset: %zx %s\n", mStart, mEnd,
mEnd - mStart, mOffset, mName.get());
for (auto& field : MemoryMapping::sFields) {
if (field.mOffset < sizeof(*this)) {
aOut.AppendPrintf(" %s: %zd\n", field.mName, ValueForField(field));
}
}
aOut.AppendPrintf(" Flags: %x\n", mFlags.serialize());
for (auto& flag : sVMFlagStrings) {
if (mFlags.contains(flag.mFlag)) {
aOut.AppendPrintf(" : %s %s\n", flag.mName, flag.mPrettyName);
}
}
}
} // namespace mozilla
|
