375 lines
13 KiB
C++
375 lines
13 KiB
C++
#pragma once
|
||
|
||
#include "hash.hh"
|
||
#include "serialise.hh"
|
||
|
||
#include <string>
|
||
#include <map>
|
||
#include <memory>
|
||
|
||
|
||
namespace nix {
|
||
|
||
|
||
typedef std::map<Path, Path> Roots;
|
||
|
||
|
||
struct GCOptions
|
||
{
|
||
/* Garbage collector operation:
|
||
|
||
- `gcReturnLive': return the set of paths reachable from
|
||
(i.e. in the closure of) the roots.
|
||
|
||
- `gcReturnDead': return the set of paths not reachable from
|
||
the roots.
|
||
|
||
- `gcDeleteDead': actually delete the latter set.
|
||
|
||
- `gcDeleteSpecific': delete the paths listed in
|
||
`pathsToDelete', insofar as they are not reachable.
|
||
*/
|
||
typedef enum {
|
||
gcReturnLive,
|
||
gcReturnDead,
|
||
gcDeleteDead,
|
||
gcDeleteSpecific,
|
||
} GCAction;
|
||
|
||
GCAction action;
|
||
|
||
/* If `ignoreLiveness' is set, then reachability from the roots is
|
||
ignored (dangerous!). However, the paths must still be
|
||
unreferenced *within* the store (i.e., there can be no other
|
||
store paths that depend on them). */
|
||
bool ignoreLiveness;
|
||
|
||
/* For `gcDeleteSpecific', the paths to delete. */
|
||
PathSet pathsToDelete;
|
||
|
||
/* Stop after at least `maxFreed' bytes have been freed. */
|
||
unsigned long long maxFreed;
|
||
|
||
GCOptions();
|
||
};
|
||
|
||
|
||
struct GCResults
|
||
{
|
||
/* Depending on the action, the GC roots, or the paths that would
|
||
be or have been deleted. */
|
||
PathSet paths;
|
||
|
||
/* For `gcReturnDead', `gcDeleteDead' and `gcDeleteSpecific', the
|
||
number of bytes that would be or was freed. */
|
||
unsigned long long bytesFreed;
|
||
|
||
GCResults()
|
||
{
|
||
bytesFreed = 0;
|
||
}
|
||
};
|
||
|
||
|
||
struct SubstitutablePathInfo
|
||
{
|
||
Path deriver;
|
||
PathSet references;
|
||
unsigned long long downloadSize; /* 0 = unknown or inapplicable */
|
||
unsigned long long narSize; /* 0 = unknown */
|
||
};
|
||
|
||
typedef std::map<Path, SubstitutablePathInfo> SubstitutablePathInfos;
|
||
|
||
|
||
struct ValidPathInfo
|
||
{
|
||
Path path;
|
||
Path deriver;
|
||
Hash hash;
|
||
PathSet references;
|
||
time_t registrationTime;
|
||
unsigned long long narSize; // 0 = unknown
|
||
unsigned long long id; // internal use only
|
||
ValidPathInfo() : registrationTime(0), narSize(0) { }
|
||
};
|
||
|
||
typedef list<ValidPathInfo> ValidPathInfos;
|
||
|
||
|
||
enum BuildMode { bmNormal, bmRepair, bmCheck };
|
||
|
||
|
||
class StoreAPI
|
||
{
|
||
public:
|
||
|
||
virtual ~StoreAPI() { }
|
||
|
||
/* Check whether a path is valid. */
|
||
virtual bool isValidPath(const Path & path) = 0;
|
||
|
||
/* Query which of the given paths is valid. */
|
||
virtual PathSet queryValidPaths(const PathSet & paths) = 0;
|
||
|
||
/* Query the set of all valid paths. */
|
||
virtual PathSet queryAllValidPaths() = 0;
|
||
|
||
/* Query information about a valid path. */
|
||
virtual ValidPathInfo queryPathInfo(const Path & path) = 0;
|
||
|
||
/* Query the hash of a valid path. */
|
||
virtual Hash queryPathHash(const Path & path) = 0;
|
||
|
||
/* Query the set of outgoing FS references for a store path. The
|
||
result is not cleared. */
|
||
virtual void queryReferences(const Path & path,
|
||
PathSet & references) = 0;
|
||
|
||
/* Queries the set of incoming FS references for a store path.
|
||
The result is not cleared. */
|
||
virtual void queryReferrers(const Path & path,
|
||
PathSet & referrers) = 0;
|
||
|
||
/* Query the deriver of a store path. Return the empty string if
|
||
no deriver has been set. */
|
||
virtual Path queryDeriver(const Path & path) = 0;
|
||
|
||
/* Return all currently valid derivations that have `path' as an
|
||
output. (Note that the result of `queryDeriver()' is the
|
||
derivation that was actually used to produce `path', which may
|
||
not exist anymore.) */
|
||
virtual PathSet queryValidDerivers(const Path & path) = 0;
|
||
|
||
/* Query the outputs of the derivation denoted by `path'. */
|
||
virtual PathSet queryDerivationOutputs(const Path & path) = 0;
|
||
|
||
/* Query the output names of the derivation denoted by `path'. */
|
||
virtual StringSet queryDerivationOutputNames(const Path & path) = 0;
|
||
|
||
/* Query the full store path given the hash part of a valid store
|
||
path, or "" if the path doesn't exist. */
|
||
virtual Path queryPathFromHashPart(const string & hashPart) = 0;
|
||
|
||
/* Query which of the given paths have substitutes. */
|
||
virtual PathSet querySubstitutablePaths(const PathSet & paths) = 0;
|
||
|
||
/* Query substitute info (i.e. references, derivers and download
|
||
sizes) of a set of paths. If a path does not have substitute
|
||
info, it's omitted from the resulting ‘infos’ map. */
|
||
virtual void querySubstitutablePathInfos(const PathSet & paths,
|
||
SubstitutablePathInfos & infos) = 0;
|
||
|
||
/* Copy the contents of a path to the store and register the
|
||
validity the resulting path. The resulting path is returned.
|
||
The function object `filter' can be used to exclude files (see
|
||
libutil/archive.hh). */
|
||
virtual Path addToStore(const string & name, const Path & srcPath,
|
||
bool recursive = true, HashType hashAlgo = htSHA256,
|
||
PathFilter & filter = defaultPathFilter, bool repair = false) = 0;
|
||
|
||
/* Like addToStore, but the contents written to the output path is
|
||
a regular file containing the given string. */
|
||
virtual Path addTextToStore(const string & name, const string & s,
|
||
const PathSet & references, bool repair = false) = 0;
|
||
|
||
/* Export a store path, that is, create a NAR dump of the store
|
||
path and append its references and its deriver. Optionally, a
|
||
cryptographic signature (created by OpenSSL) of the preceding
|
||
data is attached. */
|
||
virtual void exportPath(const Path & path, bool sign,
|
||
Sink & sink) = 0;
|
||
|
||
/* Import a sequence of NAR dumps created by exportPaths() into
|
||
the Nix store. */
|
||
virtual Paths importPaths(bool requireSignature, Source & source) = 0;
|
||
|
||
/* For each path, if it's a derivation, build it. Building a
|
||
derivation means ensuring that the output paths are valid. If
|
||
they are already valid, this is a no-op. Otherwise, validity
|
||
can be reached in two ways. First, if the output paths is
|
||
substitutable, then build the path that way. Second, the
|
||
output paths can be created by running the builder, after
|
||
recursively building any sub-derivations. For inputs that are
|
||
not derivations, substitute them. */
|
||
virtual void buildPaths(const PathSet & paths, BuildMode buildMode = bmNormal) = 0;
|
||
|
||
/* Ensure that a path is valid. If it is not currently valid, it
|
||
may be made valid by running a substitute (if defined for the
|
||
path). */
|
||
virtual void ensurePath(const Path & path) = 0;
|
||
|
||
/* Add a store path as a temporary root of the garbage collector.
|
||
The root disappears as soon as we exit. */
|
||
virtual void addTempRoot(const Path & path) = 0;
|
||
|
||
/* Add an indirect root, which is merely a symlink to `path' from
|
||
/nix/var/nix/gcroots/auto/<hash of `path'>. `path' is supposed
|
||
to be a symlink to a store path. The garbage collector will
|
||
automatically remove the indirect root when it finds that
|
||
`path' has disappeared. */
|
||
virtual void addIndirectRoot(const Path & path) = 0;
|
||
|
||
/* Acquire the global GC lock, then immediately release it. This
|
||
function must be called after registering a new permanent root,
|
||
but before exiting. Otherwise, it is possible that a running
|
||
garbage collector doesn't see the new root and deletes the
|
||
stuff we've just built. By acquiring the lock briefly, we
|
||
ensure that either:
|
||
|
||
- The collector is already running, and so we block until the
|
||
collector is finished. The collector will know about our
|
||
*temporary* locks, which should include whatever it is we
|
||
want to register as a permanent lock.
|
||
|
||
- The collector isn't running, or it's just started but hasn't
|
||
acquired the GC lock yet. In that case we get and release
|
||
the lock right away, then exit. The collector scans the
|
||
permanent root and sees our's.
|
||
|
||
In either case the permanent root is seen by the collector. */
|
||
virtual void syncWithGC() = 0;
|
||
|
||
/* Find the roots of the garbage collector. Each root is a pair
|
||
(link, storepath) where `link' is the path of the symlink
|
||
outside of the Nix store that point to `storePath'. */
|
||
virtual Roots findRoots() = 0;
|
||
|
||
/* Perform a garbage collection. */
|
||
virtual void collectGarbage(const GCOptions & options, GCResults & results) = 0;
|
||
|
||
/* Return the set of paths that have failed to build.*/
|
||
virtual PathSet queryFailedPaths() = 0;
|
||
|
||
/* Clear the "failed" status of the given paths. The special
|
||
value `*' causes all failed paths to be cleared. */
|
||
virtual void clearFailedPaths(const PathSet & paths) = 0;
|
||
|
||
/* Return a string representing information about the path that
|
||
can be loaded into the database using `nix-store --load-db' or
|
||
`nix-store --register-validity'. */
|
||
string makeValidityRegistration(const PathSet & paths,
|
||
bool showDerivers, bool showHash);
|
||
|
||
/* Optimise the disk space usage of the Nix store by hard-linking files
|
||
with the same contents. */
|
||
virtual void optimiseStore() = 0;
|
||
|
||
/* Check the integrity of the Nix store. Returns true if errors
|
||
remain. */
|
||
virtual bool verifyStore(bool checkContents, bool repair) = 0;
|
||
};
|
||
|
||
|
||
/* !!! These should be part of the store API, I guess. */
|
||
|
||
/* 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);
|
||
|
||
/* Extract the name part of the given store path. */
|
||
string storePathToName(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);
|
||
|
||
|
||
/* Follow symlinks until we end up with a path in the Nix store. */
|
||
Path followLinksToStore(const Path & path);
|
||
|
||
|
||
/* Same as followLinksToStore(), but apply toStorePath() to the
|
||
result. */
|
||
Path followLinksToStorePath(const Path & path);
|
||
|
||
|
||
/* Constructs a unique store path name. */
|
||
Path makeStorePath(const string & type,
|
||
const Hash & hash, const string & name);
|
||
|
||
Path makeOutputPath(const string & id,
|
||
const Hash & hash, const string & name);
|
||
|
||
Path makeFixedOutputPath(bool recursive,
|
||
HashType hashAlgo, Hash hash, string name);
|
||
|
||
|
||
/* This is the preparatory part of addToStore() and addToStoreFixed();
|
||
it computes the store path to which srcPath is to be copied.
|
||
Returns the store path and the cryptographic hash of the
|
||
contents of srcPath. */
|
||
std::pair<Path, Hash> computeStorePathForPath(const Path & srcPath,
|
||
bool recursive = true, HashType hashAlgo = htSHA256,
|
||
PathFilter & filter = defaultPathFilter);
|
||
|
||
/* Preparatory part of addTextToStore().
|
||
|
||
!!! Computation of the path should take the references given to
|
||
addTextToStore() into account, otherwise we have a (relatively
|
||
minor) security hole: a caller can register a source file with
|
||
bogus references. If there are too many references, the path may
|
||
not be garbage collected when it has to be (not really a problem,
|
||
the caller could create a root anyway), or it may be garbage
|
||
collected when it shouldn't be (more serious).
|
||
|
||
Hashing the references would solve this (bogus references would
|
||
simply yield a different store path, so other users wouldn't be
|
||
affected), but it has some backwards compatibility issues (the
|
||
hashing scheme changes), so I'm not doing that for now. */
|
||
Path computeStorePathForText(const string & name, const string & s,
|
||
const PathSet & references);
|
||
|
||
|
||
/* Remove the temporary roots file for this process. Any temporary
|
||
root becomes garbage after this point unless it has been registered
|
||
as a (permanent) root. */
|
||
void removeTempRoots();
|
||
|
||
|
||
/* Register a permanent GC root. */
|
||
Path addPermRoot(StoreAPI & store, const Path & storePath,
|
||
const Path & gcRoot, bool indirect, bool allowOutsideRootsDir = false);
|
||
|
||
|
||
/* Sort a set of paths topologically under the references relation.
|
||
If p refers to q, then p preceeds q in this list. */
|
||
Paths topoSortPaths(StoreAPI & store, const PathSet & paths);
|
||
|
||
|
||
/* For now, there is a single global store API object, but we'll
|
||
purify that in the future. */
|
||
extern std::shared_ptr<StoreAPI> store;
|
||
|
||
|
||
/* Factory method: open the Nix database, either through the local or
|
||
remote implementation. */
|
||
std::shared_ptr<StoreAPI> openStore(bool reserveSpace = true);
|
||
|
||
|
||
/* Display a set of paths in human-readable form (i.e., between quotes
|
||
and separated by commas). */
|
||
string showPaths(const PathSet & paths);
|
||
|
||
|
||
ValidPathInfo decodeValidPathInfo(std::istream & str,
|
||
bool hashGiven = false);
|
||
|
||
|
||
/* Export multiple paths in the format expected by ‘nix-store
|
||
--import’. */
|
||
void exportPaths(StoreAPI & store, const Paths & paths,
|
||
bool sign, Sink & sink);
|
||
|
||
|
||
MakeError(SubstError, Error)
|
||
MakeError(BuildError, Error) /* denotes a permanent build failure */
|
||
|
||
|
||
}
|