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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
40namespace fs = utils::fs;
41namespace signals = utils::signals;
42
43
44/// Shared implementation of the auto_directory.
45struct 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.
55    impl(const path& directory_) :
56        _directory(directory_),
57        _cleaned(false)
58    {
59    }
60
61    /// Destructor.
62    ~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
76    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.
92fs::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.
102fs::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.
120fs::auto_directory
121fs::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.
137const fs::path&
138fs::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.
149void
150fs::auto_directory::cleanup(void)
151{
152    _pimpl->cleanup();
153}
154
155
156/// Shared implementation of the auto_file.
157struct 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.
167    impl(const path& file_) :
168        _file(file_),
169        _removed(false)
170    {
171    }
172
173    /// Destructor.
174    ~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
188    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.
204fs::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.
214fs::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.
228fs::auto_file
229fs::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.
245const fs::path&
246fs::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.
257void
258fs::auto_file::remove(void)
259{
260    _pimpl->remove();
261}
262