From 36457566f9917dc7c0c348d012816a2ca333ef1b Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Wed, 17 Dec 2014 23:00:42 +0100 Subject: Merge branch 'nix' into 'master'. --- nix/libstore/store-api.cc | 331 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 331 insertions(+) create mode 100644 nix/libstore/store-api.cc (limited to 'nix/libstore/store-api.cc') diff --git a/nix/libstore/store-api.cc b/nix/libstore/store-api.cc new file mode 100644 index 0000000000..0238e5b0b6 --- /dev/null +++ b/nix/libstore/store-api.cc @@ -0,0 +1,331 @@ +#include "store-api.hh" +#include "globals.hh" +#include "util.hh" + +#include + + +namespace nix { + + +GCOptions::GCOptions() +{ + action = gcDeleteDead; + ignoreLiveness = false; + maxFreed = ULLONG_MAX; +} + + +bool isInStore(const Path & path) +{ + return isInDir(path, settings.nixStore); +} + + +bool isStorePath(const Path & path) +{ + return isInStore(path) + && path.find('/', settings.nixStore.size() + 1) == Path::npos; +} + + +void assertStorePath(const Path & path) +{ + if (!isStorePath(path)) + throw Error(format("path `%1%' is not in the Nix store") % path); +} + + +Path toStorePath(const Path & path) +{ + if (!isInStore(path)) + throw Error(format("path `%1%' is not in the Nix store") % path); + Path::size_type slash = path.find('/', settings.nixStore.size() + 1); + if (slash == Path::npos) + return path; + else + return Path(path, 0, slash); +} + + +Path followLinksToStore(const Path & _path) +{ + Path path = absPath(_path); + while (!isInStore(path)) { + if (!isLink(path)) break; + string target = readLink(path); + path = absPath(target, dirOf(path)); + } + if (!isInStore(path)) + throw Error(format("path `%1%' is not in the Nix store") % path); + return path; +} + + +Path followLinksToStorePath(const Path & path) +{ + return toStorePath(followLinksToStore(path)); +} + + +string storePathToName(const Path & path) +{ + assertStorePath(path); + return string(path, settings.nixStore.size() + 34); +} + + +void checkStoreName(const string & name) +{ + string validChars = "+-._?="; + /* Disallow names starting with a dot for possible security + reasons (e.g., "." and ".."). */ + if (string(name, 0, 1) == ".") + throw Error(format("illegal name: `%1%'") % name); + foreach (string::const_iterator, i, name) + if (!((*i >= 'A' && *i <= 'Z') || + (*i >= 'a' && *i <= 'z') || + (*i >= '0' && *i <= '9') || + validChars.find(*i) != string::npos)) + { + throw Error(format("invalid character `%1%' in name `%2%'") + % *i % name); + } +} + + +/* Store paths have the following form: + + /- + + where + + = the location of the Nix store, usually /nix/store + + = a human readable name for the path, typically obtained + from the name attribute of the derivation, or the name of the + source file from which the store path is created. For derivation + outputs other than the default "out" output, the string "-" + is suffixed to . + + = base-32 representation of the first 160 bits of a SHA-256 + hash of ; the hash part of the store name + + = the string ":sha256:

::"; + note that it includes the location of the store as well as the + name to make sure that changes to either of those are reflected + in the hash (e.g. you won't get /nix/store/-name1 and + /nix/store/-name2 with equal hash parts). + + = one of: + "text:::..." + for plain text files written to the store using + addTextToStore(); ... are the references of the + path. + "source" + for paths copied to the store using addToStore() when recursive + = true and hashAlgo = "sha256" + "output:" + for either the outputs created by derivations, OR paths copied + to the store using addToStore() with recursive != true or + hashAlgo != "sha256" (in that case "source" is used; it's + silly, but it's done that way for compatibility). is the + name of the output (usually, "out"). + +

= base-16 representation of a SHA-256 hash of: + if = "text:...": + the string written to the resulting store path + if = "source": + the serialisation of the path from which this store path is + copied, as returned by hashPath() + if = "output:out": + for non-fixed derivation outputs: + the derivation (see hashDerivationModulo() in + primops.cc) + for paths copied by addToStore() or produced by fixed-output + derivations: + the string "fixed:out:::", where + = "r:" for recursive (path) hashes, or "" or flat + (file) hashes + = "md5", "sha1" or "sha256" + = base-16 representation of the path or flat hash of + the contents of the path (or expected contents of the + path for fixed-output derivations) + + It would have been nicer to handle fixed-output derivations under + "source", e.g. have something like "source:", but we're + stuck with this for now... + + The main reason for this way of computing names is to prevent name + collisions (for security). For instance, it shouldn't be feasible + to come up with a derivation whose output path collides with the + path for a copied source. The former would have a starting with + "output:out:", while the latter would have a <2> starting with + "source:". +*/ + + +Path makeStorePath(const string & type, + const Hash & hash, const string & name) +{ + /* e.g., "source:sha256:1abc...:/nix/store:foo.tar.gz" */ + string s = type + ":sha256:" + printHash(hash) + ":" + + settings.nixStore + ":" + name; + + checkStoreName(name); + + return settings.nixStore + "/" + + printHash32(compressHash(hashString(htSHA256, s), 20)) + + "-" + name; +} + + +Path makeOutputPath(const string & id, + const Hash & hash, const string & name) +{ + return makeStorePath("output:" + id, hash, + name + (id == "out" ? "" : "-" + id)); +} + + +Path makeFixedOutputPath(bool recursive, + HashType hashAlgo, Hash hash, string name) +{ + return hashAlgo == htSHA256 && recursive + ? makeStorePath("source", hash, name) + : makeStorePath("output:out", hashString(htSHA256, + "fixed:out:" + (recursive ? (string) "r:" : "") + + printHashType(hashAlgo) + ":" + printHash(hash) + ":"), + name); +} + + +std::pair computeStorePathForPath(const Path & srcPath, + bool recursive, HashType hashAlgo, PathFilter & filter) +{ + HashType ht(hashAlgo); + Hash h = recursive ? hashPath(ht, srcPath, filter).first : hashFile(ht, srcPath); + string name = baseNameOf(srcPath); + Path dstPath = makeFixedOutputPath(recursive, hashAlgo, h, name); + return std::pair(dstPath, h); +} + + +Path computeStorePathForText(const string & name, const string & s, + const PathSet & references) +{ + Hash hash = hashString(htSHA256, s); + /* Stuff the references (if any) into the type. This is a bit + hacky, but we can't put them in `s' since that would be + ambiguous. */ + string type = "text"; + foreach (PathSet::const_iterator, i, references) { + type += ":"; + type += *i; + } + return makeStorePath(type, hash, name); +} + + +/* Return a string accepted by decodeValidPathInfo() that + registers the specified paths as valid. Note: it's the + responsibility of the caller to provide a closure. */ +string StoreAPI::makeValidityRegistration(const PathSet & paths, + bool showDerivers, bool showHash) +{ + string s = ""; + + foreach (PathSet::iterator, i, paths) { + s += *i + "\n"; + + ValidPathInfo info = queryPathInfo(*i); + + if (showHash) { + s += printHash(info.hash) + "\n"; + s += (format("%1%\n") % info.narSize).str(); + } + + Path deriver = showDerivers ? info.deriver : ""; + s += deriver + "\n"; + + s += (format("%1%\n") % info.references.size()).str(); + + foreach (PathSet::iterator, j, info.references) + s += *j + "\n"; + } + + return s; +} + + +ValidPathInfo decodeValidPathInfo(std::istream & str, bool hashGiven) +{ + ValidPathInfo info; + getline(str, info.path); + if (str.eof()) { info.path = ""; return info; } + if (hashGiven) { + string s; + getline(str, s); + info.hash = parseHash(htSHA256, s); + getline(str, s); + if (!string2Int(s, info.narSize)) throw Error("number expected"); + } + getline(str, info.deriver); + string s; int n; + getline(str, s); + if (!string2Int(s, n)) throw Error("number expected"); + while (n--) { + getline(str, s); + info.references.insert(s); + } + if (!str || str.eof()) throw Error("missing input"); + return info; +} + + +string showPaths(const PathSet & paths) +{ + string s; + foreach (PathSet::const_iterator, i, paths) { + if (s.size() != 0) s += ", "; + s += "`" + *i + "'"; + } + return s; +} + + +void exportPaths(StoreAPI & store, const Paths & paths, + bool sign, Sink & sink) +{ + foreach (Paths::const_iterator, i, paths) { + writeInt(1, sink); + store.exportPath(*i, sign, sink); + } + writeInt(0, sink); +} + + +} + + +#include "local-store.hh" +#include "serialise.hh" +#include "remote-store.hh" + + +namespace nix { + + +std::shared_ptr store; + + +std::shared_ptr openStore(bool reserveSpace) +{ + if (getEnv("NIX_REMOTE") == "") + return std::shared_ptr(new LocalStore(reserveSpace)); + else + return std::shared_ptr(new RemoteStore()); +} + + +} -- cgit v1.2.3