#ifndef __STORE_H
#define __STORE_H
#include <string>
#include "hash.hh"
namespace nix {
class Transaction;
/* Nix store and database schema version. Version 1 (or 0) was Nix <=
0.7. Version 2 was Nix 0.8 and 0.8. Version 3 is Nix 0.10 and
up. */
const int nixSchemaVersion = 3;
/* A substitute is a program invocation that constructs some store
path (typically by fetching it from somewhere, e.g., from the
network). */
struct Substitute
{
/* The derivation that built this store path (empty if none). */
Path deriver;
/* Program to be executed to create the store path. Must be in
the output path of `storeExpr'. */
Path program;
/* Extra arguments to be passed to the program (the first argument
is the store path to be substituted). */
Strings args;
bool operator == (const Substitute & sub) const;
};
typedef list<Substitute> Substitutes;
/* Open the database environment. If `reserveSpace' is true, make
sure that a big empty file exists in /nix/var/nix/db/reserved. If
`reserveSpace' is false, delete this file if it exists. The idea
is that on normal operation, the file exists; but when we run the
garbage collector, it is deleted. This is to ensure that the
garbage collector has a small amount of disk space available, which
is required to open the Berkeley DB environment. */
void openDB(bool reserveSpace = true);
/* Create the required database tables. */
void initDB();
/* Close the database. */
void closeDB();
/* Get a transaction object. */
void createStoreTransaction(Transaction & txn);
/* Copy a path recursively. */
void copyPath(const Path & src, const Path & dst);
/* Register a substitute. */
void registerSubstitute(const Transaction & txn,
const Path & srcPath, const Substitute & sub);
/* Return the substitutes for the given path. */
Substitutes querySubstitutes(const Transaction & txn, const Path & srcPath);
/* Deregister all substitutes. */
void clearSubstitutes();
/* 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 succesful 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 Transaction & txn,
const Path & path, const Hash & hash, const PathSet & references,
const Path & deriver);
struct ValidPathInfo
{
Path path;
Path deriver;
Hash hash;
PathSet references;
};
typedef list<ValidPathInfo> ValidPathInfos;
void registerValidPaths(const Transaction & txn,
const ValidPathInfos & infos);
/* Throw an exception if `path' is not directly in the Nix store. */
void assertStorePath(const Path & path);
bool isInStore(const Path & path);
bool isStorePath(const Path & path);
void checkStoreName(const string & name);
/* Chop off the parts after the top-level store name, e.g.,
/nix/store/abcd-foo/bar => /nix/store/abcd-foo. */
Path toStorePath(const Path & path);
/* "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 0 (i.e.,
00:00:00 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
in a setuid Nix installation. */
void canonicalisePathMetaData(const Path & path);
/* Checks whether a path is valid. */
bool isValidPathTxn(const Transaction & txn, const Path & path);
bool isValidPath(const Path & path);
/* Queries the hash of a valid path. */
Hash queryPathHash(const Path & path);
/* Sets the set of outgoing FS references for a store path. Use with
care! */
void setReferences(const Transaction & txn, const Path & storePath,
const PathSet & references);
/* Queries the set of outgoing FS references for a store path. The
result is not cleared. */
void queryReferences(const Transaction & txn,
const Path & storePath, PathSet & references);
/* Queries the set of incoming FS references for a store path. The
result is not cleared. */
void queryReferrers(const Transaction & txn,
const Path & storePath, PathSet & referrers);
/* Sets the deriver of a store path. Use with care! */
void setDeriver(const Transaction & txn, const Path & storePath,
const Path & deriver);
/* Query the deriver of a store path. Return the empty string if no
deriver has been set. */
Path queryDeriver(const Transaction & txn, const Path & storePath);
/* Constructs a unique store path name. */
Path makeStorePath(const string & type,
const Hash & hash, const string & suffix);
/* Copy the contents of a path to the store and register the validity
the resulting path. The resulting path is returned. */
Path addToStore(const Path & srcPath);
/* Like addToStore(), but for pre-adding the outputs of fixed-output
derivations. */
Path addToStoreFixed(bool recursive, string hashAlgo, const Path & srcPath);
Path makeFixedOutputPath(bool recursive,
string hashAlgo, Hash hash, string name);
/* Like addToStore, but the contents written to the output path is a
regular file containing the given string. */
Path addTextToStore(const string & suffix, const string & s,
const PathSet & references);
/* Delete a value from the nixStore directory. */
void deleteFromStore(const Path & path, unsigned long long & bytesFreed);
void verifyStore(bool checkContents);
}
#endif /* !__STORE_H */
