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28
29 #include "utils/fs/auto_cleaners.hpp"
30
31 #include "utils/format/macros.hpp"
32 #include "utils/fs/exceptions.hpp"
33 #include "utils/fs/operations.hpp"
34 #include "utils/fs/path.hpp"
35 #include "utils/logging/macros.hpp"
36 #include "utils/noncopyable.hpp"
37 #include "utils/sanity.hpp"
38 #include "utils/signals/interrupts.hpp"
39
40 namespace fs = utils::fs;
41 namespace signals = utils::signals;
42
43
44 /// Shared implementation of the auto_directory.
45 struct utils::fs::auto_directory::impl : utils::noncopyable {
46 /// The path to the directory being managed.
47 fs::path _directory;
48
49 /// Whether cleanup() has been already executed or not.
50 bool _cleaned;
51
52 /// Constructor.
53 ///
54 /// \param directory_ The directory to grab the ownership of.
implutils::fs::auto_directory::impl55 impl(const path& directory_) :
56 _directory(directory_),
57 _cleaned(false)
58 {
59 }
60
61 /// Destructor.
~implutils::fs::auto_directory::impl62 ~impl(void)
63 {
64 try {
65 this->cleanup();
66 } catch (const fs::error& e) {
67 LW(F("Failed to auto-cleanup directory '%s': %s") % _directory %
68 e.what());
69 }
70 }
71
72 /// Removes the directory.
73 ///
74 /// See the cleanup() method of the auto_directory class for details.
75 void
cleanuputils::fs::auto_directory::impl76 cleanup(void)
77 {
78 if (!_cleaned) {
79 // Mark this as cleaned first so that, in case of failure, we don't
80 // reraise the error from the destructor.
81 _cleaned = true;
82
83 fs::rmdir(_directory);
84 }
85 }
86 };
87
88
89 /// Constructs a new auto_directory and grabs ownership of a directory.
90 ///
91 /// \param directory_ The directory to grab the ownership of.
auto_directory(const path & directory_)92 fs::auto_directory::auto_directory(const path& directory_) :
93 _pimpl(new impl(directory_))
94 {
95 }
96
97
98 /// Deletes the managed directory; must be empty.
99 ///
100 /// This should not be relied on because it cannot provide proper error
101 /// reporting. Instead, the caller should use the cleanup() method.
~auto_directory(void)102 fs::auto_directory::~auto_directory(void)
103 {
104 }
105
106
107 /// Creates a self-destructing temporary directory.
108 ///
109 /// See the notes for fs::mkdtemp_public() for details on the permissions
110 /// given to the temporary directory, which are looser than what the standard
111 /// mkdtemp would grant.
112 ///
113 /// \param path_template The template for the temporary path, which is a
114 /// basename that is created within the TMPDIR. Must contain the XXXXXX
115 /// pattern, which is atomically replaced by a random unique string.
116 ///
117 /// \return The self-destructing directory.
118 ///
119 /// \throw fs::error If the creation fails.
120 fs::auto_directory
mkdtemp_public(const std::string & path_template)121 fs::auto_directory::mkdtemp_public(const std::string& path_template)
122 {
123 signals::interrupts_inhibiter inhibiter;
124 const fs::path directory_ = fs::mkdtemp_public(path_template);
125 try {
126 return auto_directory(directory_);
127 } catch (...) {
128 fs::rmdir(directory_);
129 throw;
130 }
131 }
132
133
134 /// Gets the directory managed by this auto_directory.
135 ///
136 /// \return The path to the managed directory.
137 const fs::path&
directory(void) const138 fs::auto_directory::directory(void) const
139 {
140 return _pimpl->_directory;
141 }
142
143
144 /// Deletes the managed directory; must be empty.
145 ///
146 /// This operation is idempotent.
147 ///
148 /// \throw fs::error If there is a problem removing any directory or file.
149 void
cleanup(void)150 fs::auto_directory::cleanup(void)
151 {
152 _pimpl->cleanup();
153 }
154
155
156 /// Shared implementation of the auto_file.
157 struct utils::fs::auto_file::impl : utils::noncopyable {
158 /// The path to the file being managed.
159 fs::path _file;
160
161 /// Whether removed() has been already executed or not.
162 bool _removed;
163
164 /// Constructor.
165 ///
166 /// \param file_ The file to grab the ownership of.
implutils::fs::auto_file::impl167 impl(const path& file_) :
168 _file(file_),
169 _removed(false)
170 {
171 }
172
173 /// Destructor.
~implutils::fs::auto_file::impl174 ~impl(void)
175 {
176 try {
177 this->remove();
178 } catch (const fs::error& e) {
179 LW(F("Failed to auto-cleanup file '%s': %s") % _file %
180 e.what());
181 }
182 }
183
184 /// Removes the file.
185 ///
186 /// See the remove() method of the auto_file class for details.
187 void
removeutils::fs::auto_file::impl188 remove(void)
189 {
190 if (!_removed) {
191 // Mark this as cleaned first so that, in case of failure, we don't
192 // reraise the error from the destructor.
193 _removed = true;
194
195 fs::unlink(_file);
196 }
197 }
198 };
199
200
201 /// Constructs a new auto_file and grabs ownership of a file.
202 ///
203 /// \param file_ The file to grab the ownership of.
auto_file(const path & file_)204 fs::auto_file::auto_file(const path& file_) :
205 _pimpl(new impl(file_))
206 {
207 }
208
209
210 /// Deletes the managed file.
211 ///
212 /// This should not be relied on because it cannot provide proper error
213 /// reporting. Instead, the caller should use the remove() method.
~auto_file(void)214 fs::auto_file::~auto_file(void)
215 {
216 }
217
218
219 /// Creates a self-destructing temporary file.
220 ///
221 /// \param path_template The template for the temporary path, which is a
222 /// basename that is created within the TMPDIR. Must contain the XXXXXX
223 /// pattern, which is atomically replaced by a random unique string.
224 ///
225 /// \return The self-destructing file.
226 ///
227 /// \throw fs::error If the creation fails.
228 fs::auto_file
mkstemp(const std::string & path_template)229 fs::auto_file::mkstemp(const std::string& path_template)
230 {
231 signals::interrupts_inhibiter inhibiter;
232 const fs::path file_ = fs::mkstemp(path_template);
233 try {
234 return auto_file(file_);
235 } catch (...) {
236 fs::unlink(file_);
237 throw;
238 }
239 }
240
241
242 /// Gets the file managed by this auto_file.
243 ///
244 /// \return The path to the managed file.
245 const fs::path&
file(void) const246 fs::auto_file::file(void) const
247 {
248 return _pimpl->_file;
249 }
250
251
252 /// Deletes the managed file.
253 ///
254 /// This operation is idempotent.
255 ///
256 /// \throw fs::error If there is a problem removing the file.
257 void
remove(void)258 fs::auto_file::remove(void)
259 {
260 _pimpl->remove();
261 }
262