aboutsummaryrefslogtreecommitdiffstats
path: root/src/Mapper.cxx
blob: e2d082122cefa2dd37de7be112368d58ba3ec8bf (plain) (blame)
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
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
/*
 * Copyright (C) 2003-2013 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/*
 * Maps directory and song objects to file system paths.
 */

#include "config.h"
#include "Mapper.hxx"
#include "Directory.hxx"
#include "Song.hxx"
#include "fs/Path.hxx"
#include "fs/FileSystem.hxx"
#include "fs/DirectoryReader.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"

#include <glib.h>

#include <assert.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <dirent.h>

static constexpr Domain mapper_domain("mapper");

/**
 * The absolute path of the music directory encoded in UTF-8.
 */
static char *music_dir_utf8;
static size_t music_dir_utf8_length;

/**
 * The absolute path of the music directory encoded in the filesystem
 * character set.
 */
static Path music_dir_fs = Path::Null();
static size_t music_dir_fs_length;

/**
 * The absolute path of the playlist directory encoded in the
 * filesystem character set.
 */
static Path playlist_dir_fs = Path::Null();

/**
 * Duplicate a string, chop all trailing slashes.
 */
static char *
strdup_chop_slash(const char *path_fs)
{
	size_t length = strlen(path_fs);

	while (length > 0 && path_fs[length - 1] == G_DIR_SEPARATOR)
		--length;

	return g_strndup(path_fs, length);
}

static void
check_directory(const char *path_utf8, const Path &path_fs)
{
	struct stat st;
	if (!StatFile(path_fs, st)) {
		FormatErrno(mapper_domain,
			    "Failed to stat directory \"%s\"",
			    path_utf8);
		return;
	}

	if (!S_ISDIR(st.st_mode)) {
		FormatError(mapper_domain,
			    "Not a directory: %s", path_utf8);
		return;
	}

#ifndef WIN32
	const Path x = Path::Build(path_fs, ".");
	if (!StatFile(x, st) && errno == EACCES)
		FormatError(mapper_domain,
			    "No permission to traverse (\"execute\") directory: %s",
			    path_utf8);
#endif

	const DirectoryReader reader(path_fs);
	if (reader.HasFailed() && errno == EACCES)
		FormatError(mapper_domain,
			    "No permission to read directory: %s", path_utf8);
}

static void
mapper_set_music_dir(Path &&path)
{
	assert(!path.IsNull());

	music_dir_fs = std::move(path);
	music_dir_fs_length = music_dir_fs.length();

	const auto utf8 = music_dir_fs.ToUTF8();
	music_dir_utf8 = strdup_chop_slash(utf8.c_str());
	music_dir_utf8_length = strlen(music_dir_utf8);

	check_directory(music_dir_utf8, music_dir_fs);
}

static void
mapper_set_playlist_dir(Path &&path)
{
	assert(!path.IsNull());

	playlist_dir_fs = std::move(path);

	const auto utf8 = playlist_dir_fs.ToUTF8();
	check_directory(utf8.c_str(), playlist_dir_fs);
}

void
mapper_init(Path &&_music_dir, Path &&_playlist_dir)
{
	if (!_music_dir.IsNull())
		mapper_set_music_dir(std::move(_music_dir));

	if (!_playlist_dir.IsNull())
		mapper_set_playlist_dir(std::move(_playlist_dir));
}

void mapper_finish(void)
{
	g_free(music_dir_utf8);
}

const char *
mapper_get_music_directory_utf8(void)
{
	return music_dir_utf8;
}

const Path &
mapper_get_music_directory_fs(void)
{
	return music_dir_fs;
}

const char *
map_to_relative_path(const char *path_utf8)
{
	return music_dir_utf8 != NULL &&
		memcmp(path_utf8, music_dir_utf8,
		       music_dir_utf8_length) == 0 &&
		G_IS_DIR_SEPARATOR(path_utf8[music_dir_utf8_length])
		? path_utf8 + music_dir_utf8_length + 1
		: path_utf8;
}

Path
map_uri_fs(const char *uri)
{
	assert(uri != NULL);
	assert(*uri != '/');

	if (music_dir_fs.IsNull())
		return Path::Null();

	const Path uri_fs = Path::FromUTF8(uri);
	if (uri_fs.IsNull())
		return Path::Null();

	return Path::Build(music_dir_fs, uri_fs);
}

Path
map_directory_fs(const Directory *directory)
{
	assert(music_dir_utf8 != NULL);
	assert(!music_dir_fs.IsNull());

	if (directory->IsRoot())
		return music_dir_fs;

	return map_uri_fs(directory->GetPath());
}

Path
map_directory_child_fs(const Directory *directory, const char *name)
{
	assert(music_dir_utf8 != NULL);
	assert(!music_dir_fs.IsNull());

	/* check for invalid or unauthorized base names */
	if (*name == 0 || strchr(name, '/') != NULL ||
	    strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
		return Path::Null();

	const Path parent_fs = map_directory_fs(directory);
	if (parent_fs.IsNull())
		return Path::Null();

	const Path name_fs = Path::FromUTF8(name);
	if (name_fs.IsNull())
		return Path::Null();

	return Path::Build(parent_fs, name_fs);
}

/**
 * Map a song object that was created by song_dup_detached().  It does
 * not have a real parent directory, only the dummy object
 * #detached_root.
 */
static Path
map_detached_song_fs(const char *uri_utf8)
{
	Path uri_fs = Path::FromUTF8(uri_utf8);
	if (uri_fs.IsNull())
		return Path::Null();

	return Path::Build(music_dir_fs, uri_fs);
}

Path
map_song_fs(const Song *song)
{
	assert(song->IsFile());

	if (song->IsInDatabase())
		return song->IsDetached()
			? map_detached_song_fs(song->uri)
			: map_directory_child_fs(song->parent, song->uri);
	else
		return Path::FromUTF8(song->uri);
}

char *
map_fs_to_utf8(const char *path_fs)
{
	if (!music_dir_fs.IsNull() &&
	    strncmp(path_fs, music_dir_fs.c_str(), music_dir_fs_length) == 0 &&
	    G_IS_DIR_SEPARATOR(path_fs[music_dir_fs_length]))
		/* remove musicDir prefix */
		path_fs += music_dir_fs_length + 1;
	else if (G_IS_DIR_SEPARATOR(path_fs[0]))
		/* not within musicDir */
		return NULL;

	while (path_fs[0] == G_DIR_SEPARATOR)
		++path_fs;

	const std::string path_utf8 = Path::ToUTF8(path_fs);
	if (path_utf8.empty())
		return nullptr;

	return g_strdup(path_utf8.c_str());
}

const Path &
map_spl_path(void)
{
	return playlist_dir_fs;
}

Path
map_spl_utf8_to_fs(const char *name)
{
	if (playlist_dir_fs.IsNull())
		return Path::Null();

	char *filename_utf8 = g_strconcat(name, PLAYLIST_FILE_SUFFIX, NULL);
	const Path filename_fs = Path::FromUTF8(filename_utf8);
	g_free(filename_utf8);
	if (filename_fs.IsNull())
		return Path::Null();

	return Path::Build(playlist_dir_fs, filename_fs);
}