aboutsummaryrefslogtreecommitdiff
path: root/nix/libstore/local-store.hh
blob: 54331e448a94bc22a3d5f1ebaceb3e6adf990e96 (plain)
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
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
#pragma once

#include <string>

#include "store-api.hh"
#include "util.hh"
#include "pathlocks.hh"

#if HAVE_TR1_UNORDERED_SET
#include <tr1/unordered_set>
#endif



class sqlite3;
class sqlite3_stmt;


namespace nix {


/* Nix store and database schema version.  Version 1 (or 0) was Nix <=
   0.7.  Version 2 was Nix 0.8 and 0.9.  Version 3 is Nix 0.10.
   Version 4 is Nix 0.11.  Version 5 is Nix 0.12-0.16.  Version 6 is
   Nix 1.0.  Version 7 is Nix 1.3. */
const int nixSchemaVersion = 7;


extern string drvsLogDir;


struct Derivation;


struct OptimiseStats
{
    unsigned long filesLinked;
    unsigned long long bytesFreed;
    unsigned long long blocksFreed;
    OptimiseStats()
    {
        filesLinked = 0;
        bytesFreed = blocksFreed = 0;
    }
};


struct RunningSubstituter
{
    Path program;
    Pid pid;
    AutoCloseFD to, from, error;
    FdSource fromBuf;
    bool disabled;
    RunningSubstituter() : disabled(false) { };
};


/* Wrapper object to close the SQLite database automatically. */
struct SQLite
{
    sqlite3 * db;
    SQLite() { db = 0; }
    ~SQLite();
    operator sqlite3 * () { return db; }
};


/* Wrapper object to create and destroy SQLite prepared statements. */
struct SQLiteStmt
{
    sqlite3 * db;
    sqlite3_stmt * stmt;
    unsigned int curArg;
    SQLiteStmt() { stmt = 0; }
    void create(sqlite3 * db, const string & s);
    void reset();
    ~SQLiteStmt();
    operator sqlite3_stmt * () { return stmt; }
    void bind(const string & value);
    void bind(int value);
    void bind64(long long value);
    void bind();
};


class LocalStore : public StoreAPI
{
private:
    typedef std::map<Path, RunningSubstituter> RunningSubstituters;
    RunningSubstituters runningSubstituters;

    Path linksDir;

public:

    /* Initialise the local store, upgrading the schema if
       necessary. */
    LocalStore(bool reserveSpace = true);

    ~LocalStore();

    /* Implementations of abstract store API methods. */

    bool isValidPath(const Path & path);

    PathSet queryValidPaths(const PathSet & paths);

    PathSet queryAllValidPaths();

    ValidPathInfo queryPathInfo(const Path & path);

    Hash queryPathHash(const Path & path);

    void queryReferences(const Path & path, PathSet & references);

    void queryReferrers(const Path & path, PathSet & referrers);

    Path queryDeriver(const Path & path);

    PathSet queryValidDerivers(const Path & path);

    PathSet queryDerivationOutputs(const Path & path);

    StringSet queryDerivationOutputNames(const Path & path);

    Path queryPathFromHashPart(const string & hashPart);

    PathSet querySubstitutablePaths(const PathSet & paths);

    void querySubstitutablePathInfos(const Path & substituter,
        PathSet & paths, SubstitutablePathInfos & infos);

    void querySubstitutablePathInfos(const PathSet & paths,
        SubstitutablePathInfos & infos);

    Path addToStore(const Path & srcPath,
        bool recursive = true, HashType hashAlgo = htSHA256,
        PathFilter & filter = defaultPathFilter, bool repair = false);

    /* Like addToStore(), but the contents of the path are contained
       in `dump', which is either a NAR serialisation (if recursive ==
       true) or simply the contents of a regular file (if recursive ==
       false). */
    Path addToStoreFromDump(const string & dump, const string & name,
        bool recursive = true, HashType hashAlgo = htSHA256, bool repair = false);

    Path addTextToStore(const string & name, const string & s,
        const PathSet & references, bool repair = false);

    void exportPath(const Path & path, bool sign,
        Sink & sink);

    Paths importPaths(bool requireSignature, Source & source);

    void buildPaths(const PathSet & paths, BuildMode buildMode);

    void ensurePath(const Path & path);

    void addTempRoot(const Path & path);

    void addIndirectRoot(const Path & path);

    void syncWithGC();

    Roots findRoots();

    void collectGarbage(const GCOptions & options, GCResults & results);

    /* Optimise the disk space usage of the Nix store by hard-linking
       files with the same contents. */
    void optimiseStore(OptimiseStats & stats);

    /* Optimise a single store path. */
    void optimisePath(const Path & path);

    /* Check the integrity of the Nix store.  Returns true if errors
       remain. */
    bool verifyStore(bool checkContents, bool repair);

    /* Register the validity of a path, i.e., that `path' exists, that
       the paths referenced by it exists, and in the case of an output
       path of a derivation, that it has been produced by a successful
       execution of the derivation (or something equivalent).  Also
       register the hash of the file system contents of the path.  The
       hash must be a SHA-256 hash. */
    void registerValidPath(const ValidPathInfo & info);

    void registerValidPaths(const ValidPathInfos & infos);

    /* Register that the build of a derivation with output `path' has
       failed. */
    void registerFailedPath(const Path & path);

    /* Query whether `path' previously failed to build. */
    bool hasPathFailed(const Path & path);

    PathSet queryFailedPaths();

    void clearFailedPaths(const PathSet & paths);

    void vacuumDB();

    /* Repair the contents of the given path by redownloading it using
       a substituter (if available). */
    void repairPath(const Path & path);

    /* Check whether the given valid path exists and has the right
       contents. */
    bool pathContentsGood(const Path & path);

    void markContentsGood(const Path & path);

    void setSubstituterEnv();

private:

    Path schemaPath;

    /* Lock file used for upgrading. */
    AutoCloseFD globalLock;

    /* The SQLite database object. */
    SQLite db;

    /* Some precompiled SQLite statements. */
    SQLiteStmt stmtRegisterValidPath;
    SQLiteStmt stmtUpdatePathInfo;
    SQLiteStmt stmtAddReference;
    SQLiteStmt stmtQueryPathInfo;
    SQLiteStmt stmtQueryReferences;
    SQLiteStmt stmtQueryReferrers;
    SQLiteStmt stmtInvalidatePath;
    SQLiteStmt stmtRegisterFailedPath;
    SQLiteStmt stmtHasPathFailed;
    SQLiteStmt stmtQueryFailedPaths;
    SQLiteStmt stmtClearFailedPath;
    SQLiteStmt stmtAddDerivationOutput;
    SQLiteStmt stmtQueryValidDerivers;
    SQLiteStmt stmtQueryDerivationOutputs;
    SQLiteStmt stmtQueryPathFromHashPart;

    /* Cache for pathContentsGood(). */
    std::map<Path, bool> pathContentsGoodCache;

    bool didSetSubstituterEnv;

    int getSchema();

    void openDB(bool create);

    void makeStoreWritable();

    unsigned long long queryValidPathId(const Path & path);

    unsigned long long addValidPath(const ValidPathInfo & info, bool checkOutputs = true);

    void addReference(unsigned long long referrer, unsigned long long reference);

    void appendReferrer(const Path & from, const Path & to, bool lock);

    void rewriteReferrers(const Path & path, bool purge, PathSet referrers);

    void invalidatePath(const Path & path);

    /* Delete a path from the Nix store. */
    void invalidatePathChecked(const Path & path);

    void verifyPath(const Path & path, const PathSet & store,
        PathSet & done, PathSet & validPaths, bool repair, bool & errors);

    void updatePathInfo(const ValidPathInfo & info);

    void upgradeStore6();
    void upgradeStore7();
    PathSet queryValidPathsOld();
    ValidPathInfo queryPathInfoOld(const Path & path);

    struct GCState;

    void deleteGarbage(GCState & state, const Path & path);

    void tryToDelete(GCState & state, const Path & path);

    bool canReachRoot(GCState & state, PathSet & visited, const Path & path);

    void deletePathRecursive(GCState & state, const Path & path);

    bool isActiveTempFile(const GCState & state,
        const Path & path, const string & suffix);

    int openGCLock(LockType lockType);

    void removeUnusedLinks(const GCState & state);

    void startSubstituter(const Path & substituter,
        RunningSubstituter & runningSubstituter);

    string getLineFromSubstituter(RunningSubstituter & run);

    template<class T> T getIntLineFromSubstituter(RunningSubstituter & run);

    Path createTempDirInStore();

    Path importPath(bool requireSignature, Source & source);

    void checkDerivationOutputs(const Path & drvPath, const Derivation & drv);

#if HAVE_TR1_UNORDERED_SET
    typedef std::tr1::unordered_set<ino_t> InodeHash;
#else
    typedef std::set<ino_t> InodeHash;
#endif

    InodeHash loadInodeHash();
    Strings readDirectoryIgnoringInodes(const Path & path, const InodeHash & inodeHash);
    void optimisePath_(OptimiseStats & stats, const Path & path, InodeHash & inodeHash);

    // Internal versions that are not wrapped in retry_sqlite.
    bool isValidPath_(const Path & path);
    void queryReferrers_(const Path & path, PathSet & referrers);
};


typedef std::pair<dev_t, ino_t> Inode;
typedef set<Inode> InodesSeen;


/* "Fix", or canonicalise, the meta-data of the files in a store path
   after it has been built.  In particular:
   - the last modification date on each file is set to 1 (i.e.,
     00:00:01 1/1/1970 UTC)
   - the permissions are set of 444 or 555 (i.e., read-only with or
     without execute permission; setuid bits etc. are cleared)
   - the owner and group are set to the Nix user and group, if we're
     running as root. */
void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen);
void canonicalisePathMetaData(const Path & path, uid_t fromUid);

void canonicaliseTimestampAndPermissions(const Path & path);

MakeError(PathInUse, Error);

}