1// Copyright (c) 2009 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/platform_file.h"
6
7#include <fcntl.h>
8#include <errno.h>
9#include <sys/stat.h>
10
11#include "base/eintr_wrapper.h"
12#include "base/file_path.h"
13#include "base/logging.h"
14#include "base/utf_string_conversions.h"
15
16namespace base {
17
18#if defined(OS_OPENBSD) || defined(OS_FREEBSD) || \
19    (defined(OS_MACOSX) && \
20     MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5)
21typedef struct stat stat_wrapper_t;
22static int CallFstat(int fd, stat_wrapper_t *sb) {
23  return fstat(fd, sb);
24}
25#else
26typedef struct stat64 stat_wrapper_t;
27static int CallFstat(int fd, stat_wrapper_t *sb) {
28  return fstat64(fd, sb);
29}
30#endif
31
32// TODO(erikkay): does it make sense to support PLATFORM_FILE_EXCLUSIVE_* here?
33PlatformFile CreatePlatformFile(const FilePath& name, int flags,
34                                bool* created, PlatformFileError* error_code) {
35  int open_flags = 0;
36  if (flags & PLATFORM_FILE_CREATE)
37    open_flags = O_CREAT | O_EXCL;
38
39  if (flags & PLATFORM_FILE_CREATE_ALWAYS) {
40    DCHECK(!open_flags);
41    open_flags = O_CREAT | O_TRUNC;
42  }
43
44  if (!open_flags && !(flags & PLATFORM_FILE_OPEN) &&
45      !(flags & PLATFORM_FILE_OPEN_ALWAYS)) {
46    NOTREACHED();
47    errno = EOPNOTSUPP;
48    *error_code = error_code ? PLATFORM_FILE_ERROR_FAILED : PLATFORM_FILE_OK;
49    return kInvalidPlatformFileValue;
50  }
51
52  if (flags & PLATFORM_FILE_WRITE && flags & PLATFORM_FILE_READ) {
53    open_flags |= O_RDWR;
54  } else if (flags & PLATFORM_FILE_WRITE) {
55    open_flags |= O_WRONLY;
56  } else if (!(flags & PLATFORM_FILE_READ) &&
57             !(flags & PLATFORM_FILE_WRITE_ATTRIBUTES) &&
58             !(flags & PLATFORM_FILE_OPEN_ALWAYS)) {
59    NOTREACHED();
60  }
61
62  if (flags & PLATFORM_FILE_TRUNCATE) {
63    DCHECK(flags & PLATFORM_FILE_WRITE);
64    open_flags |= O_TRUNC;
65  }
66
67  COMPILE_ASSERT(O_RDONLY == 0, O_RDONLY_must_equal_zero);
68
69  int descriptor =
70      HANDLE_EINTR(open(name.value().c_str(), open_flags, S_IRUSR | S_IWUSR));
71
72  if (flags & PLATFORM_FILE_OPEN_ALWAYS) {
73    if (descriptor > 0) {
74      if (created)
75        *created = false;
76    } else {
77      open_flags |= O_CREAT;
78      if (flags & PLATFORM_FILE_EXCLUSIVE_READ ||
79          flags & PLATFORM_FILE_EXCLUSIVE_WRITE) {
80        open_flags |= O_EXCL;   // together with O_CREAT implies O_NOFOLLOW
81      }
82      descriptor = HANDLE_EINTR(
83          open(name.value().c_str(), open_flags, S_IRUSR | S_IWUSR));
84      if (created && descriptor > 0)
85        *created = true;
86    }
87  }
88
89  if (created && (descriptor > 0) &&
90      (flags & (PLATFORM_FILE_CREATE_ALWAYS | PLATFORM_FILE_CREATE)))
91    *created = true;
92
93  if ((descriptor > 0) && (flags & PLATFORM_FILE_DELETE_ON_CLOSE)) {
94    unlink(name.value().c_str());
95  }
96
97  if (error_code) {
98    if (descriptor >= 0)
99      *error_code = PLATFORM_FILE_OK;
100    else {
101      switch (errno) {
102        case EACCES:
103        case EISDIR:
104        case EROFS:
105        case EPERM:
106          *error_code = PLATFORM_FILE_ERROR_ACCESS_DENIED;
107          break;
108        case ETXTBSY:
109          *error_code = PLATFORM_FILE_ERROR_IN_USE;
110          break;
111        case EEXIST:
112          *error_code = PLATFORM_FILE_ERROR_EXISTS;
113          break;
114        case ENOENT:
115          *error_code = PLATFORM_FILE_ERROR_NOT_FOUND;
116          break;
117        case EMFILE:
118          *error_code = PLATFORM_FILE_ERROR_TOO_MANY_OPENED;
119          break;
120        case ENOMEM:
121          *error_code = PLATFORM_FILE_ERROR_NO_MEMORY;
122          break;
123        case ENOSPC:
124          *error_code = PLATFORM_FILE_ERROR_NO_SPACE;
125          break;
126        case ENOTDIR:
127          *error_code = PLATFORM_FILE_ERROR_NOT_A_DIRECTORY;
128          break;
129        default:
130          *error_code = PLATFORM_FILE_ERROR_FAILED;
131      }
132    }
133  }
134
135  return descriptor;
136}
137
138bool ClosePlatformFile(PlatformFile file) {
139  return !HANDLE_EINTR(close(file));
140}
141
142int ReadPlatformFile(PlatformFile file, int64 offset, char* data, int size) {
143  if (file < 0)
144    return -1;
145
146  return HANDLE_EINTR(pread(file, data, size, offset));
147}
148
149int WritePlatformFile(PlatformFile file, int64 offset,
150                      const char* data, int size) {
151  if (file < 0)
152    return -1;
153
154  return HANDLE_EINTR(pwrite(file, data, size, offset));
155}
156
157bool TruncatePlatformFile(PlatformFile file, int64 length) {
158  return ((file >= 0) && !HANDLE_EINTR(ftruncate(file, length)));
159}
160
161bool FlushPlatformFile(PlatformFile file) {
162  return !HANDLE_EINTR(fsync(file));
163}
164
165bool TouchPlatformFile(PlatformFile file, const base::Time& last_access_time,
166                       const base::Time& last_modified_time) {
167#ifdef ANDROID
168  // futimes() isn't actually POSIX.
169  // TODO: Check all callers to see if this needs to work correctly on Android.
170  return false;
171#else
172  if (file < 0)
173    return false;
174
175  timeval times[2];
176  times[0] = last_access_time.ToTimeVal();
177  times[1] = last_modified_time.ToTimeVal();
178  return !futimes(file, times);
179#endif
180}
181
182bool GetPlatformFileInfo(PlatformFile file, PlatformFileInfo* info) {
183  if (!info)
184    return false;
185
186  stat_wrapper_t file_info;
187  if (CallFstat(file, &file_info))
188    return false;
189
190  info->is_directory = S_ISDIR(file_info.st_mode);
191  info->is_symbolic_link = S_ISLNK(file_info.st_mode);
192  info->size = file_info.st_size;
193  info->last_modified = base::Time::FromTimeT(file_info.st_mtime);
194  info->last_accessed = base::Time::FromTimeT(file_info.st_atime);
195  info->creation_time = base::Time::FromTimeT(file_info.st_ctime);
196  return true;
197}
198
199}  // namespace base
200