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
|
/* -*- 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 "AutoMemMap.h"
#include "ScriptPreloader-inl.h"
#include "mozilla/Try.h"
#include "mozilla/ipc/FileDescriptor.h"
#include "nsIFile.h"
#include <private/pprio.h>
namespace mozilla {
namespace loader {
using namespace mozilla::ipc;
AutoMemMap::~AutoMemMap() { reset(); }
FileDescriptor AutoMemMap::cloneFileDescriptor() const {
if (fd.get()) {
auto handle =
FileDescriptor::PlatformHandleType(PR_FileDesc2NativeHandle(fd.get()));
return FileDescriptor(handle);
}
return FileDescriptor();
}
Result<Ok, nsresult> AutoMemMap::init(nsIFile* file, int flags, int mode,
PRFileMapProtect prot) {
MOZ_ASSERT(!fd);
MOZ_TRY(file->OpenNSPRFileDesc(flags, mode, getter_Transfers(fd)));
return initInternal(prot);
}
Result<Ok, nsresult> AutoMemMap::init(const FileDescriptor& file,
PRFileMapProtect prot, size_t maybeSize) {
MOZ_ASSERT(!fd);
if (!file.IsValid()) {
return Err(NS_ERROR_INVALID_ARG);
}
auto handle = file.ClonePlatformHandle();
fd.reset(PR_ImportFile(PROsfd(handle.get())));
if (!fd) {
return Err(NS_ERROR_FAILURE);
}
(void)handle.release();
return initInternal(prot, maybeSize);
}
Result<Ok, nsresult> AutoMemMap::initInternal(PRFileMapProtect prot,
size_t maybeSize) {
MOZ_ASSERT(!fileMap);
MOZ_ASSERT(!addr);
if (maybeSize > 0) {
// Some OSes' shared memory objects can't be stat()ed, either at
// all (Android) or without loosening the sandbox (Mac) so just
// use the size.
size_ = maybeSize;
} else {
// But if we don't have the size, assume it's a regular file and
// ask for it.
PRFileInfo64 fileInfo;
MOZ_TRY(PR_GetOpenFileInfo64(fd.get(), &fileInfo));
if (fileInfo.size > UINT32_MAX) {
return Err(NS_ERROR_INVALID_ARG);
}
size_ = fileInfo.size;
}
fileMap = PR_CreateFileMap(fd.get(), 0, prot);
if (!fileMap) {
return Err(NS_ERROR_FAILURE);
}
addr = PR_MemMap(fileMap, 0, size_);
if (!addr) {
return Err(NS_ERROR_FAILURE);
}
return Ok();
}
FileDescriptor AutoMemMap::cloneHandle() const { return cloneFileDescriptor(); }
void AutoMemMap::reset() {
if (addr && !persistent_) {
(void)NS_WARN_IF(PR_MemUnmap(addr, size()) != PR_SUCCESS);
addr = nullptr;
}
if (fileMap) {
(void)NS_WARN_IF(PR_CloseFileMap(fileMap) != PR_SUCCESS);
fileMap = nullptr;
}
fd = nullptr;
}
} // namespace loader
} // namespace mozilla
|
