* Rename all those main.cc files.

src/nix-store/nix-store.cc

@@ -0,0 +1,731 @@
+#include <iostream>
+#include <algorithm>
+
+#include "globals.hh"
+#include "misc.hh"
+#include "archive.hh"
+#include "shared.hh"
+#include "dotgraph.hh"
+#include "local-store.hh"
+#include "db.hh"
+#include "util.hh"
+#include "help.txt.hh"
+
+
+using namespace nix;
+using std::cin;
+using std::cout;
+
+
+typedef void (* Operation) (Strings opFlags, Strings opArgs);
+
+
+void printHelp()
+{
+    cout << string((char *) helpText, sizeof helpText);
+}
+
+
+static Path gcRoot;
+static int rootNr = 0;
+static bool indirectRoot = false;
+
+
+static Path fixPath(Path path)
+{
+    path = absPath(path);
+    while (!isInStore(path)) {
+        if (!isLink(path)) break;
+        string target = readLink(path);
+        path = absPath(target, dirOf(path));
+    }
+    return toStorePath(path);
+}
+
+
+static Path useDeriver(Path path)
+{       
+    if (!isDerivation(path)) {
+        path = queryDeriver(noTxn, path);
+        if (path == "")
+            throw Error(format("deriver of path `%1%' is not known") % path);
+    }
+    return path;
+}
+
+
+/* Realisation the given path.  For a derivation that means build it;
+   for other paths it means ensure their validity. */
+static Path realisePath(const Path & path)
+{
+    if (isDerivation(path)) {
+        PathSet paths;
+        paths.insert(path);
+        store->buildDerivations(paths);
+        Path outPath = findOutput(derivationFromPath(path), "out");
+        
+        if (gcRoot == "")
+            printGCWarning();
+        else
+            outPath = addPermRoot(outPath,
+                makeRootName(gcRoot, rootNr),
+                indirectRoot);
+        
+        return outPath;
+    } else {
+        store->ensurePath(path);
+        return path;
+    }
+}
+
+
+/* Realise the given paths. */
+static void opRealise(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+
+    for (Strings::iterator i = opArgs.begin();
+         i != opArgs.end(); ++i)
+        *i = fixPath(*i);
+            
+    if (opArgs.size() > 1) {
+        PathSet drvPaths;
+        for (Strings::iterator i = opArgs.begin();
+             i != opArgs.end(); ++i)
+            if (isDerivation(*i))
+                drvPaths.insert(*i);
+        store->buildDerivations(drvPaths);
+    }
+
+    for (Strings::iterator i = opArgs.begin();
+         i != opArgs.end(); ++i)
+        cout << format("%1%\n") % realisePath(*i);
+}
+
+
+/* Add files to the Nix store and print the resulting paths. */
+static void opAdd(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+
+    for (Strings::iterator i = opArgs.begin(); i != opArgs.end(); ++i)
+        cout << format("%1%\n") % store->addToStore(*i);
+}
+
+
+/* Preload the output of a fixed-output derivation into the Nix
+   store. */
+static void opAddFixed(Strings opFlags, Strings opArgs)
+{
+    bool recursive = false;
+    
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--recursive") recursive = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    if (opArgs.empty())
+        throw UsageError("first argument must be hash algorithm");
+    
+    string hashAlgo = opArgs.front();
+    opArgs.pop_front();
+
+    for (Strings::iterator i = opArgs.begin(); i != opArgs.end(); ++i)
+        cout << format("%1%\n") % store->addToStore(*i, true, recursive, hashAlgo);
+}
+
+
+static Hash parseHash16or32(HashType ht, const string & s)
+{
+    return s.size() == Hash(ht).hashSize * 2
+        ? parseHash(ht, s)
+        : parseHash32(ht, s);
+}
+
+
+/* Hack to support caching in `nix-prefetch-url'. */
+static void opPrintFixedPath(Strings opFlags, Strings opArgs)
+{
+    bool recursive = false;
+    
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--recursive") recursive = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    Strings::iterator i = opArgs.begin();
+    string hashAlgo = *i++;
+    string hash = *i++;
+    string name = *i++;
+
+    cout << format("%1%\n") %
+        makeFixedOutputPath(recursive, hashAlgo,
+            parseHash16or32(parseHashType(hashAlgo), hash), name);
+}
+
+
+/* Place in `paths' the set of paths that are required to `realise'
+   the given store path, i.e., all paths necessary for valid
+   deployment of the path.  For a derivation, this is the union of
+   requisites of the inputs, plus the derivation; for other store
+   paths, it is the set of paths in the FS closure of the path.  If
+   `includeOutputs' is true, include the requisites of the output
+   paths of derivations as well.
+
+   Note that this function can be used to implement three different
+   deployment policies:
+
+   - Source deployment (when called on a derivation).
+   - Binary deployment (when called on an output path).
+   - Source/binary deployment (when called on a derivation with
+     `includeOutputs' set to true).
+*/
+static void storePathRequisites(const Path & storePath,
+    bool includeOutputs, PathSet & paths)
+{
+    computeFSClosure(storePath, paths);
+
+    if (includeOutputs) {
+        for (PathSet::iterator i = paths.begin();
+             i != paths.end(); ++i)
+            if (isDerivation(*i)) {
+                Derivation drv = derivationFromPath(*i);
+                for (DerivationOutputs::iterator j = drv.outputs.begin();
+                     j != drv.outputs.end(); ++j)
+                    if (store->isValidPath(j->second.path))
+                        computeFSClosure(j->second.path, paths);
+            }
+    }
+}
+
+
+static Path maybeUseOutput(const Path & storePath, bool useOutput, bool forceRealise)
+{
+    if (forceRealise) realisePath(storePath);
+    if (useOutput && isDerivation(storePath)) {
+        Derivation drv = derivationFromPath(storePath);
+        return findOutput(drv, "out");
+    }
+    else return storePath;
+}
+
+
+static void printPathSet(const PathSet & paths)
+{
+    for (PathSet::iterator i = paths.begin(); 
+         i != paths.end(); ++i)
+        cout << format("%s\n") % *i;
+}
+
+
+/* Some code to print a tree representation of a derivation dependency
+   graph.  Topological sorting is used to keep the tree relatively
+   flat. */
+
+const string treeConn = "+---";
+const string treeLine = "|   ";
+const string treeNull = "    ";
+
+
+static void dfsVisit(const PathSet & paths, const Path & path,
+    PathSet & visited, Paths & sorted)
+{
+    if (visited.find(path) != visited.end()) return;
+    visited.insert(path);
+    
+    PathSet closure;
+    computeFSClosure(path, closure);
+    
+    for (PathSet::iterator i = closure.begin();
+         i != closure.end(); ++i)
+        if (*i != path && paths.find(*i) != paths.end())
+            dfsVisit(paths, *i, visited, sorted);
+
+    sorted.push_front(path);
+}
+
+
+static Paths topoSort(const PathSet & paths)
+{
+    Paths sorted;
+    PathSet visited;
+    for (PathSet::const_iterator i = paths.begin(); i != paths.end(); ++i)
+        dfsVisit(paths, *i, visited, sorted);
+    return sorted;
+}
+
+
+static void printTree(const Path & path,
+    const string & firstPad, const string & tailPad, PathSet & done)
+{
+    if (done.find(path) != done.end()) {
+        cout << format("%1%%2% [...]\n") % firstPad % path;
+        return;
+    }
+    done.insert(path);
+
+    cout << format("%1%%2%\n") % firstPad % path;
+
+    PathSet references;
+    store->queryReferences(path, references);
+    
+#if 0     
+    for (PathSet::iterator i = drv.inputSrcs.begin();
+         i != drv.inputSrcs.end(); ++i)
+        cout << format("%1%%2%\n") % (tailPad + treeConn) % *i;
+#endif    
+
+    /* Topologically sort under the relation A < B iff A \in
+       closure(B).  That is, if derivation A is an (possibly indirect)
+       input of B, then A is printed first.  This has the effect of
+       flattening the tree, preventing deeply nested structures.  */
+    Paths sorted = topoSort(references);
+    reverse(sorted.begin(), sorted.end());
+
+    for (Paths::iterator i = sorted.begin(); i != sorted.end(); ++i) {
+        Paths::iterator j = i; ++j;
+        printTree(*i, tailPad + treeConn,
+            j == sorted.end() ? tailPad + treeNull : tailPad + treeLine,
+            done);
+    }
+}
+
+
+/* Perform various sorts of queries. */
+static void opQuery(Strings opFlags, Strings opArgs)
+{
+    enum { qOutputs, qRequisites, qReferences, qReferrers
+         , qReferrersClosure, qDeriver, qBinding, qHash
+         , qTree, qGraph } query = qOutputs;
+    bool useOutput = false;
+    bool includeOutputs = false;
+    bool forceRealise = false;
+    string bindingName;
+
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--outputs") query = qOutputs;
+        else if (*i == "--requisites" || *i == "-R") query = qRequisites;
+        else if (*i == "--references") query = qReferences;
+        else if (*i == "--referrers" || *i == "--referers") query = qReferrers;
+        else if (*i == "--referrers-closure" || *i == "--referers-closure") query = qReferrersClosure;
+        else if (*i == "--deriver" || *i == "-d") query = qDeriver;
+        else if (*i == "--binding" || *i == "-b") {
+            if (opArgs.size() == 0)
+                throw UsageError("expected binding name");
+            bindingName = opArgs.front();
+            opArgs.pop_front();
+            query = qBinding;
+        }
+        else if (*i == "--hash") query = qHash;
+        else if (*i == "--tree") query = qTree;
+        else if (*i == "--graph") query = qGraph;
+        else if (*i == "--use-output" || *i == "-u") useOutput = true;
+        else if (*i == "--force-realise" || *i == "-f") forceRealise = true;
+        else if (*i == "--include-outputs") includeOutputs = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    switch (query) {
+        
+        case qOutputs: {
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+            {
+                *i = fixPath(*i);
+                if (forceRealise) realisePath(*i);
+                Derivation drv = derivationFromPath(*i);
+                cout << format("%1%\n") % findOutput(drv, "out");
+            }
+            break;
+        }
+
+        case qRequisites:
+        case qReferences:
+        case qReferrers:
+        case qReferrersClosure: {
+            PathSet paths;
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+            {
+                Path path = maybeUseOutput(fixPath(*i), useOutput, forceRealise);
+                if (query == qRequisites)
+                    storePathRequisites(path, includeOutputs, paths);
+                else if (query == qReferences) store->queryReferences(path, paths);
+                else if (query == qReferrers) store->queryReferrers(path,  paths);
+                else if (query == qReferrersClosure) computeFSClosure(path, paths, true);
+            }
+            printPathSet(paths);
+            break;
+        }
+
+        case qDeriver:
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+            {
+                Path deriver = queryDeriver(noTxn, fixPath(*i));
+                cout << format("%1%\n") %
+                    (deriver == "" ? "unknown-deriver" : deriver);
+            }
+            break;
+
+        case qBinding:
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+            {
+                Path path = useDeriver(fixPath(*i));
+                Derivation drv = derivationFromPath(path);
+                StringPairs::iterator j = drv.env.find(bindingName);
+                if (j == drv.env.end())
+                    throw Error(format("derivation `%1%' has no environment binding named `%2%'")
+                        % path % bindingName);
+                cout << format("%1%\n") % j->second;
+            }
+            break;
+
+        case qHash:
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+            {
+                Path path = maybeUseOutput(fixPath(*i), useOutput, forceRealise);
+                Hash hash = store->queryPathHash(path);
+                assert(hash.type == htSHA256);
+                cout << format("sha256:%1%\n") % printHash32(hash);
+            }
+            break;
+
+        case qTree: {
+            PathSet done;
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+                printTree(fixPath(*i), "", "", done);
+            break;
+        }
+            
+        case qGraph: {
+            PathSet roots;
+            for (Strings::iterator i = opArgs.begin();
+                 i != opArgs.end(); ++i)
+                roots.insert(maybeUseOutput(fixPath(*i), useOutput, forceRealise));
+	    printDotGraph(roots);
+            break;
+        }
+
+        default:
+            abort();
+    }
+}
+
+
+static void opReadLog(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+
+    for (Strings::iterator i = opArgs.begin();
+         i != opArgs.end(); ++i)
+    {
+        Path path = useDeriver(fixPath(*i));
+        
+        Path logPath = (format("%1%/%2%/%3%") %
+            nixLogDir % drvsLogDir % baseNameOf(path)).str();
+
+        if (!pathExists(logPath))
+            throw Error(format("build log of derivation `%1%' is not available") % path);
+
+        /* !!! Make this run in O(1) memory. */
+        string log = readFile(logPath);
+        writeFull(STDOUT_FILENO, (const unsigned char *) log.c_str(), log.size());
+    }
+}
+
+
+static void opRegisterSubstitutes(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (!opArgs.empty()) throw UsageError("no arguments expected");
+
+    Transaction txn;
+    createStoreTransaction(txn);
+
+    while (1) {
+        Path srcPath;
+        Substitute sub;
+        PathSet references;
+        getline(cin, srcPath);
+        if (cin.eof()) break;
+        getline(cin, sub.deriver);
+        getline(cin, sub.program);
+        string s; int n;
+        getline(cin, s);
+        if (!string2Int(s, n)) throw Error("number expected");
+        while (n--) {
+            getline(cin, s);
+            sub.args.push_back(s);
+        }
+        getline(cin, s);
+        if (!string2Int(s, n)) throw Error("number expected");
+        while (n--) {
+            getline(cin, s);
+            references.insert(s);
+        }
+        if (!cin || cin.eof()) throw Error("missing input");
+        registerSubstitute(txn, srcPath, sub);
+        setReferences(txn, srcPath, references);
+    }
+
+    txn.commit();
+}
+
+
+static void opClearSubstitutes(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (!opArgs.empty())
+        throw UsageError("no arguments expected");
+
+    clearSubstitutes();
+}
+
+
+static void opRegisterValidity(Strings opFlags, Strings opArgs)
+{
+    bool reregister = false; // !!! maybe this should be the default
+        
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--reregister") reregister = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    if (!opArgs.empty()) throw UsageError("no arguments expected");
+
+    ValidPathInfos infos;
+    
+    while (1) {
+        ValidPathInfo info;
+        getline(cin, info.path);
+        if (cin.eof()) break;
+        getline(cin, info.deriver);
+        string s; int n;
+        getline(cin, s);
+        if (!string2Int(s, n)) throw Error("number expected");
+        while (n--) {
+            getline(cin, s);
+            info.references.insert(s);
+        }
+        if (!cin || cin.eof()) throw Error("missing input");
+        if (!store->isValidPath(info.path) || reregister) {
+            /* !!! races */
+            canonicalisePathMetaData(info.path);
+            info.hash = hashPath(htSHA256, info.path);
+            infos.push_back(info);
+        }
+    }
+
+    Transaction txn;
+    createStoreTransaction(txn);
+    registerValidPaths(txn, infos);
+    txn.commit();
+}
+
+
+static void opCheckValidity(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+
+    for (Strings::iterator i = opArgs.begin();
+         i != opArgs.end(); ++i)
+        if (!store->isValidPath(*i))
+            throw Error(format("path `%1%' is not valid") % *i);
+}
+
+
+struct PrintFreed 
+{
+    bool show, dryRun;
+    unsigned long long bytesFreed;
+    PrintFreed(bool show, bool dryRun)
+        : show(show), dryRun(dryRun), bytesFreed(0) { }
+    ~PrintFreed() 
+    {
+        if (show)
+            cout << format(
+                (dryRun
+                    ? "%d bytes would be freed (%.2f MiB)\n"
+                    : "%d bytes freed (%.2f MiB)\n"))
+                % bytesFreed % (bytesFreed / (1024.0 * 1024.0));
+    }
+};
+
+
+static void opGC(Strings opFlags, Strings opArgs)
+{
+    GCAction action = gcDeleteDead;
+    
+    /* Do what? */
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--print-roots") action = gcReturnRoots;
+        else if (*i == "--print-live") action = gcReturnLive;
+        else if (*i == "--print-dead") action = gcReturnDead;
+        else if (*i == "--delete") action = gcDeleteDead;
+        else throw UsageError(format("bad sub-operation `%1%' in GC") % *i);
+
+    PathSet result;
+    PrintFreed freed(action == gcDeleteDead || action == gcReturnDead,
+        action == gcReturnDead);
+    store->collectGarbage(action, PathSet(), false, result, freed.bytesFreed);
+
+    if (action != gcDeleteDead) {
+        for (PathSet::iterator i = result.begin(); i != result.end(); ++i)
+            cout << *i << std::endl;
+    }
+}
+
+
+/* Remove paths from the Nix store if possible (i.e., if they do not
+   have any remaining referrers and are not reachable from any GC
+   roots). */
+static void opDelete(Strings opFlags, Strings opArgs)
+{
+    bool ignoreLiveness = false;
+    
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--ignore-liveness") ignoreLiveness = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    PathSet pathsToDelete;
+    for (Strings::iterator i = opArgs.begin();
+         i != opArgs.end(); ++i)
+        pathsToDelete.insert(fixPath(*i));
+    
+    PathSet dummy;
+    PrintFreed freed(true, false);
+    store->collectGarbage(gcDeleteSpecific, pathsToDelete, ignoreLiveness,
+        dummy, freed.bytesFreed);
+}
+
+
+/* Dump a path as a Nix archive.  The archive is written to standard
+   output. */
+static void opDump(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (opArgs.size() != 1) throw UsageError("only one argument allowed");
+
+    FdSink sink(STDOUT_FILENO);
+    string path = *opArgs.begin();
+    dumpPath(path, sink);
+}
+
+
+/* Restore a value from a Nix archive.  The archive is read from
+   standard input. */
+static void opRestore(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (opArgs.size() != 1) throw UsageError("only one argument allowed");
+
+    FdSource source(STDIN_FILENO);
+    restorePath(*opArgs.begin(), source);
+}
+
+
+/* Initialise the Nix databases. */
+static void opInit(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (!opArgs.empty())
+        throw UsageError("no arguments expected");
+    /* Doesn't do anything right now; database tables are initialised
+       automatically. */
+}
+
+
+/* Verify the consistency of the Nix environment. */
+static void opVerify(Strings opFlags, Strings opArgs)
+{
+    if (!opArgs.empty())
+        throw UsageError("no arguments expected");
+
+    bool checkContents = false;
+    
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--check-contents") checkContents = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+    
+    verifyStore(checkContents);
+}
+
+
+/* Scan the arguments; find the operation, set global flags, put all
+   other flags in a list, and put all other arguments in another
+   list. */
+void run(Strings args)
+{
+    Strings opFlags, opArgs;
+    Operation op = 0;
+
+    for (Strings::iterator i = args.begin(); i != args.end(); ) {
+        string arg = *i++;
+
+        Operation oldOp = op;
+
+        if (arg == "--realise" || arg == "-r")
+            op = opRealise;
+        else if (arg == "--add" || arg == "-A")
+            op = opAdd;
+        else if (arg == "--add-fixed")
+            op = opAddFixed;
+        else if (arg == "--print-fixed-path")
+            op = opPrintFixedPath;
+        else if (arg == "--delete")
+            op = opDelete;
+        else if (arg == "--query" || arg == "-q")
+            op = opQuery;
+        else if (arg == "--read-log" || arg == "-l")
+            op = opReadLog;
+        else if (arg == "--register-substitutes")
+            op = opRegisterSubstitutes;
+        else if (arg == "--clear-substitutes")
+            op = opClearSubstitutes;
+        else if (arg == "--register-validity")
+            op = opRegisterValidity;
+        else if (arg == "--check-validity")
+            op = opCheckValidity;
+        else if (arg == "--gc")
+            op = opGC;
+        else if (arg == "--dump")
+            op = opDump;
+        else if (arg == "--restore")
+            op = opRestore;
+        else if (arg == "--init")
+            op = opInit;
+        else if (arg == "--verify")
+            op = opVerify;
+        else if (arg == "--add-root") {
+            if (i == args.end())
+                throw UsageError("`--add-root requires an argument");
+            gcRoot = absPath(*i++);
+        }
+        else if (arg == "--indirect")
+            indirectRoot = true;
+        else if (arg[0] == '-')
+            opFlags.push_back(arg);
+        else
+            opArgs.push_back(arg);
+
+        if (oldOp && oldOp != op)
+            throw UsageError("only one operation may be specified");
+    }
+
+    if (!op) throw UsageError("no operation specified");
+
+    if (op != opDump && op != opRestore) /* !!! hack */
+        store = openStore(op != opGC);
+
+    op(opFlags, opArgs);
+}
+
+
+string programId = "nix-store";