1 // Copyright 2014 The PDFium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #include "core/fxcrt/cfx_fileaccess_posix.h"
8
9 #include <fcntl.h>
10 #include <sys/stat.h>
11 #include <unistd.h>
12
13 #include <memory>
14
15 #include "core/fxcrt/fx_stream.h"
16 #include "core/fxcrt/numerics/safe_conversions.h"
17
18 #ifndef O_BINARY
19 #define O_BINARY 0
20 #endif // O_BINARY
21
22 #ifndef O_LARGEFILE
23 #define O_LARGEFILE 0
24 #endif // O_LARGEFILE
25
26 // static
Create()27 std::unique_ptr<FileAccessIface> FileAccessIface::Create() {
28 return std::make_unique<CFX_FileAccess_Posix>();
29 }
30
CFX_FileAccess_Posix()31 CFX_FileAccess_Posix::CFX_FileAccess_Posix() : m_nFD(-1) {}
32
~CFX_FileAccess_Posix()33 CFX_FileAccess_Posix::~CFX_FileAccess_Posix() {
34 Close();
35 }
36
Open(ByteStringView fileName)37 bool CFX_FileAccess_Posix::Open(ByteStringView fileName) {
38 if (m_nFD > -1)
39 return false;
40
41 // TODO(tsepez): check usage of c_str() below.
42 m_nFD =
43 open(fileName.unterminated_c_str(), O_BINARY | O_LARGEFILE | O_RDONLY);
44 return m_nFD > -1;
45 }
46
Close()47 void CFX_FileAccess_Posix::Close() {
48 if (m_nFD < 0) {
49 return;
50 }
51 close(m_nFD);
52 m_nFD = -1;
53 }
54
GetSize() const55 FX_FILESIZE CFX_FileAccess_Posix::GetSize() const {
56 if (m_nFD < 0) {
57 return 0;
58 }
59 struct stat s = {};
60 fstat(m_nFD, &s);
61 return pdfium::checked_cast<FX_FILESIZE>(s.st_size);
62 }
63
GetPosition() const64 FX_FILESIZE CFX_FileAccess_Posix::GetPosition() const {
65 if (m_nFD < 0) {
66 return (FX_FILESIZE)-1;
67 }
68 return lseek(m_nFD, 0, SEEK_CUR);
69 }
70
SetPosition(FX_FILESIZE pos)71 FX_FILESIZE CFX_FileAccess_Posix::SetPosition(FX_FILESIZE pos) {
72 if (m_nFD < 0) {
73 return (FX_FILESIZE)-1;
74 }
75 return lseek(m_nFD, pos, SEEK_SET);
76 }
77
Read(pdfium::span<uint8_t> buffer)78 size_t CFX_FileAccess_Posix::Read(pdfium::span<uint8_t> buffer) {
79 if (m_nFD < 0) {
80 return 0;
81 }
82 return read(m_nFD, buffer.data(), buffer.size());
83 }
84
Write(pdfium::span<const uint8_t> buffer)85 size_t CFX_FileAccess_Posix::Write(pdfium::span<const uint8_t> buffer) {
86 if (m_nFD < 0) {
87 return 0;
88 }
89 return write(m_nFD, buffer.data(), buffer.size());
90 }
91
ReadPos(pdfium::span<uint8_t> buffer,FX_FILESIZE pos)92 size_t CFX_FileAccess_Posix::ReadPos(pdfium::span<uint8_t> buffer,
93 FX_FILESIZE pos) {
94 if (m_nFD < 0) {
95 return 0;
96 }
97 if (pos >= GetSize()) {
98 return 0;
99 }
100 if (SetPosition(pos) == (FX_FILESIZE)-1) {
101 return 0;
102 }
103 return Read(buffer);
104 }
105
Flush()106 bool CFX_FileAccess_Posix::Flush() {
107 if (m_nFD < 0)
108 return false;
109
110 return fsync(m_nFD) > -1;
111 }
112
Truncate(FX_FILESIZE szFile)113 bool CFX_FileAccess_Posix::Truncate(FX_FILESIZE szFile) {
114 if (m_nFD < 0)
115 return false;
116
117 return !ftruncate(m_nFD, szFile);
118 }
119