From 73c53935d00660301e9408beabf1c80d6ef48610 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Mon, 24 Mar 2003 17:49:56 +0000 Subject: * For efficiency: md5 integrated into nix. * Command `nix ensure' which is like `nix getpkg' except that if the has refers to a run action it will just ensure that the imports are there. * Command `nix closure' to print out the closure of the set of descriptors under the import relation, starting at a set of roots. This can be used for garbage collection (e.g., given a list of `activated' packages, we can delete all packages not reachable from those). * Command `nix graph' to print out a Dot graph of the dependency graph. * `nix-addroot' adds a root for the (unimplemented) garbage collector. --- src/nix.cc | 258 ++++++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 195 insertions(+), 63 deletions(-) (limited to 'src/nix.cc') diff --git a/src/nix.cc b/src/nix.cc index d53a809b72..4ff49eabd0 100644 --- a/src/nix.cc +++ b/src/nix.cc @@ -4,6 +4,8 @@ #include #include #include +#include +#include #include #include @@ -14,6 +16,10 @@ #include +extern "C" { +#include "md5.h" +} + using namespace std; @@ -146,8 +152,20 @@ void enumDB(const string & dbname, DBPairs & contents) } +string printHash(unsigned char * buf) +{ + ostringstream str; + for (int i = 0; i < 16; i++) { + str.fill('0'); + str.width(2); + str << hex << (int) buf[i]; + } + return str.str(); +} + + /* Verify that a reference is valid (that is, is a MD5 hash code). */ -void checkRef(const string & s) +void checkHash(const string & s) { string err = "invalid reference: " + s; if (s.length() != 32) @@ -162,31 +180,36 @@ void checkRef(const string & s) /* Compute the MD5 hash of a file. */ -string makeRef(string filename) +string hashFile(string filename) { - char hash[33]; + unsigned char hash[16]; + FILE * file = fopen(filename.c_str(), "rb"); + if (!file) + throw BadRefError("file `" + filename + "' does not exist"); + int err = md5_stream(file, hash); + fclose(file); + if (err) throw BadRefError("cannot hash file"); + return printHash(hash); +} - FILE * pipe = popen(("md5sum " + filename + " 2> /dev/null").c_str(), "r"); - if (!pipe) throw BadRefError("cannot execute md5sum"); - if (fread(hash, 32, 1, pipe) != 1) - throw BadRefError("cannot read hash from md5sum of " + filename); - hash[32] = 0; +typedef map Params; - pclose(pipe); - checkRef(hash); - return hash; -} +void readPkgDescr(const string & hash, + Params & pkgImports, Params & fileImports, Params & arguments) +{ + string pkgfile; + if (!queryDB(dbRefs, hash, pkgfile)) + throw Error("unknown package " + hash); -typedef pair Param; -typedef list Params; + // cerr << "reading information about " + hash + " from " + pkgfile + "\n"; + /* Verify that the file hasn't changed. !!! race */ + if (hashFile(pkgfile) != hash) + throw Error("file " + pkgfile + " is stale"); -void readPkgDescr(const string & pkgfile, - Params & pkgImports, Params & fileImports, Params & arguments) -{ ifstream file; file.exceptions(ios::badbit); file.open(pkgfile.c_str()); @@ -206,13 +229,13 @@ void readPkgDescr(const string & pkgfile, str >> name >> op >> ref; if (op == "<-") { - checkRef(ref); - pkgImports.push_back(Param(name, ref)); + checkHash(ref); + pkgImports[name] = ref; } else if (op == "=") { - checkRef(ref); - fileImports.push_back(Param(name, ref)); + checkHash(ref); + fileImports[name] = ref; } else if (op == ":") - arguments.push_back(Param(name, ref)); + arguments[name] = ref; else throw Error("invalid operator " + op); } } @@ -226,20 +249,9 @@ typedef map Environment; void fetchDeps(string hash, Environment & env) { - string pkgfile; - - if (!queryDB(dbRefs, hash, pkgfile)) - throw Error("unknown package " + hash); - - cerr << "reading information about " + hash + " from " + pkgfile + "\n"; - - /* Verify that the file hasn't changed. !!! race */ - if (makeRef(pkgfile) != hash) - throw Error("file " + pkgfile + " is stale"); - /* Read the package description file. */ Params pkgImports, fileImports, arguments; - readPkgDescr(pkgfile, pkgImports, fileImports, arguments); + readPkgDescr(hash, pkgImports, fileImports, arguments); /* Recursively fetch all the dependencies, filling in the environment as we go along. */ @@ -264,7 +276,7 @@ void fetchDeps(string hash, Environment & env) if (!queryDB(dbRefs, it->second, file)) throw Error("unknown file " + it->second); - if (makeRef(file) != it->second) + if (hashFile(file) != it->second) throw Error("file " + file + " is stale"); env[it->first] = file; @@ -374,7 +386,7 @@ void installPkg(string hash) string getPkg(string hash) { string path; - checkRef(hash); + checkHash(hash); while (!queryDB(dbInstPkgs, hash, path)) installPkg(hash); return path; @@ -434,6 +446,20 @@ void runPkg(string hash) } +void ensurePkg(string hash) +{ + Params pkgImports, fileImports, arguments; + readPkgDescr(hash, pkgImports, fileImports, arguments); + + if (fileImports.find("build") != fileImports.end()) + getPkg(hash); + else if (fileImports.find("run") != fileImports.end()) { + Environment env; + fetchDeps(hash, env); + } else throw Error("invalid descriptor"); +} + + string absPath(string filename) { if (filename[0] != '/') { @@ -450,14 +476,14 @@ string absPath(string filename) void registerFile(string filename) { filename = absPath(filename); - setDB(dbRefs, makeRef(filename), filename); + setDB(dbRefs, hashFile(filename), filename); } /* This is primarily used for bootstrapping. */ void registerInstalledPkg(string hash, string path) { - checkRef(hash); + checkHash(hash); if (path == "") delDB(dbInstPkgs, hash); else @@ -483,8 +509,10 @@ void verifyDB() it != fileRefs.end(); it++) { try { - if (makeRef(it->second) != it->first) + if (hashFile(it->second) != it->first) { + cerr << "file " << it->second << " has changed\n"; delDB(dbRefs, it->first); + } } catch (BadRefError e) { /* !!! better error check */ cerr << "file " << it->second << " has disappeared\n"; delDB(dbRefs, it->first); @@ -519,48 +547,136 @@ void listInstalledPkgs() for (DBPairs::iterator it = instPkgs.begin(); it != instPkgs.end(); it++) + cout << it->first << endl; +} + + +void printInfo(vector hashes) +{ + for (vector::iterator it = hashes.begin(); + it != hashes.end(); it++) { - string descr; - if (!queryDB(dbRefs, it->first, descr)) - descr = "descriptor missing"; - cout << it->first << " " << descr << endl; + try { + Params pkgImports, fileImports, arguments; + readPkgDescr(*it, pkgImports, fileImports, arguments); + cout << *it << " " << getFromEnv(arguments, "id") << endl; + } catch (Error & e) { + cout << *it << " (descriptor missing)\n"; + } } } -void run(int argc, char * * argv) +void computeClosure(const vector & rootHashes, + set & result) +{ + list workList(rootHashes.begin(), rootHashes.end()); + set doneSet; + + while (!workList.empty()) { + string hash = workList.front(); + workList.pop_front(); + + if (doneSet.find(hash) == doneSet.end()) { + doneSet.insert(hash); + + Params pkgImports, fileImports, arguments; + readPkgDescr(hash, pkgImports, fileImports, arguments); + + for (Params::iterator it = pkgImports.begin(); + it != pkgImports.end(); it++) + workList.push_back(it->second); + } + } + + result = doneSet; +} + + +void printClosure(const vector & rootHashes) +{ + set allHashes; + computeClosure(rootHashes, allHashes); + for (set::iterator it = allHashes.begin(); + it != allHashes.end(); it++) + cout << *it << endl; +} + + +string dotQuote(const string & s) +{ + return "\"" + s + "\""; +} + + +void printGraph(vector rootHashes) +{ + set allHashes; + computeClosure(rootHashes, allHashes); + + cout << "digraph G {\n"; + + for (set::iterator it = allHashes.begin(); + it != allHashes.end(); it++) + { + Params pkgImports, fileImports, arguments; + readPkgDescr(*it, pkgImports, fileImports, arguments); + + cout << dotQuote(*it) << "[label = \"" + << getFromEnv(arguments, "id") + << "\"];\n"; + + for (Params::iterator it2 = pkgImports.begin(); + it2 != pkgImports.end(); it2++) + cout << dotQuote(it2->second) << " -> " + << dotQuote(*it) << ";\n"; + } + + cout << "}\n"; +} + + +void run(vector args) { UsageError argcError("wrong number of arguments"); string cmd; - if (argc < 1) - throw UsageError("no command specified"); - - cmd = argv[0]; - argc--, argv++; + if (args.size() < 1) throw UsageError("no command specified"); + + cmd = args[0]; + args.erase(args.begin()); // O(n) if (cmd == "init") { - if (argc != 0) throw argcError; + if (args.size() != 0) throw argcError; initDB(); } else if (cmd == "verify") { - if (argc != 0) throw argcError; + if (args.size() != 0) throw argcError; verifyDB(); } else if (cmd == "getpkg") { - if (argc != 1) throw argcError; - string path = getPkg(argv[0]); + if (args.size() != 1) throw argcError; + string path = getPkg(args[0]); cout << path << endl; } else if (cmd == "run") { - if (argc != 1) throw argcError; - runPkg(argv[0]); + if (args.size() != 1) throw argcError; + runPkg(args[0]); + } else if (cmd == "ensure") { + if (args.size() != 1) throw argcError; + ensurePkg(args[0]); } else if (cmd == "regfile") { - if (argc != 1) throw argcError; - registerFile(argv[0]); + if (args.size() != 1) throw argcError; + registerFile(args[0]); } else if (cmd == "reginst") { - if (argc != 2) throw argcError; - registerInstalledPkg(argv[0], argv[1]); + if (args.size() != 2) throw argcError; + registerInstalledPkg(args[0], args[1]); } else if (cmd == "listinst") { - if (argc != 0) throw argcError; + if (args.size() != 0) throw argcError; listInstalledPkgs(); + } else if (cmd == "info") { + printInfo(args); + } else if (cmd == "closure") { + printClosure(args); + } else if (cmd == "graph") { + printGraph(args); } else throw UsageError("unknown command: " + string(cmd)); } @@ -594,6 +710,20 @@ Subcommands: run HASH Run the descriptor referenced by HASH. + + ensure HASH + Like getpkg, but if HASH refers to a run descriptor, fetch only + the dependencies. + + info HASH... + Print information about the specified descriptors. + + closure HASH... + Determine the closure of the set of descriptors under the import + relation, starting at the given roots. + + graph HASH... + Like closure, but print a dot graph specification. "; } @@ -630,11 +760,13 @@ void main2(int argc, char * * argv) } } - argc -= optind, argv += optind; - run(argc, argv); + vector args; + argc--, argv++; + while (argc--) args.push_back(*argv++); + run(args); } - + int main(int argc, char * * argv) { prog = argv[0]; -- cgit 1.4.1