diff options
Diffstat (limited to 'src/nix-env')
| -rw-r--r-- | src/nix-env/main.cc | 132 |
1 files changed, 112 insertions, 20 deletions
diff --git a/src/nix-env/main.cc b/src/nix-env/main.cc index 4296ce5090c4..26b0ed3f5ee4 100644 --- a/src/nix-env/main.cc +++ b/src/nix-env/main.cc @@ -16,7 +16,7 @@ struct DrvInfo Path outPath; }; -typedef map<string, DrvInfo> DrvInfos; +typedef map<Path, DrvInfo> DrvInfos; bool parseDerivation(EvalState & state, Expr e, DrvInfo & drv) @@ -46,16 +46,30 @@ bool parseDerivation(EvalState & state, Expr e, DrvInfo & drv) bool parseDerivations(EvalState & state, Expr e, DrvInfos & drvs) { + ATMatcher m; + ATermList es; + e = evalExpr(state, e); - ATermMap drvMap; - queryAllAttrs(e, drvMap); - - for (ATermIterator i(drvMap.keys()); i; ++i) { - DrvInfo drv; - debug(format("evaluating attribute `%1%'") % *i); - if (parseDerivation(state, drvMap.get(*i), drv)) - drvs[drv.name] = drv; + if (atMatch(m, e) >> "Attrs") { + ATermMap drvMap; + queryAllAttrs(e, drvMap); + + for (ATermIterator i(drvMap.keys()); i; ++i) { + DrvInfo drv; + debug(format("evaluating attribute `%1%'") % *i); + if (parseDerivation(state, drvMap.get(*i), drv)) + drvs[drv.drvPath] = drv; + } + } + + else if (atMatch(m, e) >> "List" >> es) { + for (ATermIterator i(es); i; ++i) { + DrvInfo drv; + debug(format("evaluating list element") % *i); + if (parseDerivation(state, *i, drv)) + drvs[drv.drvPath] = drv; + } } return true; @@ -76,6 +90,26 @@ static Path getLinksDir() } +static Path getCurrentPath() +{ + return getLinksDir() + "/current"; +} + + +void queryInstalled(EvalState & state, DrvInfos & drvs) +{ + Path path = getCurrentPath() + "/manifest"; + + if (!pathExists(path)) return; /* not an error, assume nothing installed */ + + Expr e = ATreadFromNamedFile(path.c_str()); + if (!e) throw Error(format("cannot read Nix expression from `%1%'") % path); + + if (!parseDerivations(state, e, drvs)) + throw badTerm(format("expected set of derivations in `%1%'") % path, e); +} + + Path createLink(Path outPath, Path drvPath) { Path linksDir = getLinksDir(); @@ -86,18 +120,40 @@ Path createLink(Path outPath, Path drvPath) for (Strings::iterator i = names.begin(); i != names.end(); ++i) { istringstream s(*i); unsigned int n; - if (s >> n && s.eof() && n > num) num = n + 1; + if (s >> n && s.eof() && n >= num) num = n + 1; } - Path linkPath = (format("%1%/%2%") % linksDir % num).str(); + Path linkPath; - if (symlink(outPath.c_str(), linkPath.c_str()) != 0) - throw SysError(format("creating symlink `%1%'") % linkPath); + while (1) { + linkPath = (format("%1%/%2%") % linksDir % num).str(); + if (symlink(outPath.c_str(), linkPath.c_str()) == 0) break; + if (errno != EEXIST) + throw SysError(format("creating symlink `%1%'") % linkPath); + /* Somebody beat us to it, retry with a higher number. */ + num++; + } return linkPath; } +void switchLink(Path link, Path target) +{ + Path tmp = canonPath(dirOf(link) + "/.new_" + baseNameOf(link)); + if (symlink(target.c_str(), tmp.c_str()) != 0) + throw SysError(format("creating symlink `%1%'") % tmp); + /* The rename() system call is supposed to be essentially atomic + on Unix. That is, if we have links `current -> X' and + `new_current -> Y', and we rename new_current to current, a + process accessing current will see X or Y, but never a + file-not-found or other error condition. This is sufficient to + atomically switch user environments. */ + if (rename(tmp.c_str(), link.c_str()) != 0) + throw SysError(format("renaming `%1%' to `%2%'") % tmp % link); +} + + void installDerivations(EvalState & state, Path nePath, Strings drvNames) { @@ -107,18 +163,30 @@ void installDerivations(EvalState & state, DrvInfos availDrvs; loadDerivations(state, nePath, availDrvs); + typedef map<string, Path> NameMap; + NameMap nameMap; + + for (DrvInfos::iterator i = availDrvs.begin(); + i != availDrvs.end(); ++i) + nameMap[i->second.name] = i->first; + /* Filter out the ones we're not interested in. */ DrvInfos selectedDrvs; for (Strings::iterator i = drvNames.begin(); i != drvNames.end(); ++i) { - DrvInfos::iterator j = availDrvs.find(*i); - if (j == availDrvs.end()) + NameMap::iterator j = nameMap.find(*i); + if (j == nameMap.end()) throw Error(format("unknown derivation `%1%'") % *i); else - selectedDrvs[j->first] = j->second; + selectedDrvs[j->second] = availDrvs[j->second]; } + /* Add in the already installed derivations. */ + DrvInfos installedDrvs; + queryInstalled(state, installedDrvs); + selectedDrvs.insert(installedDrvs.begin(), installedDrvs.end()); + /* Get the environment builder expression. */ Expr envBuilder = parseExprFromFile("/home/eelco/nix/corepkgs/buildenv"); /* !!! */ @@ -168,14 +236,14 @@ void installDerivations(EvalState & state, /* Switch the current user environment to the output path. */ debug(format("switching to new user environment")); Path linkPath = createLink(topLevelDrv.outPath, topLevelDrv.drvPath); -// switchLink(current"), link); + switchLink(getLinksDir() + "/current", linkPath); } static void opInstall(EvalState & state, Strings opFlags, Strings opArgs) { - if (opArgs.size() < 1) throw UsageError("Nix expression expected"); + if (opArgs.size() < 1) throw UsageError("Nix file expected"); Path nePath = opArgs.front(); opArgs.pop_front(); @@ -188,12 +256,14 @@ static void opInstall(EvalState & state, static void opQuery(EvalState & state, Strings opFlags, Strings opArgs) { - enum { qName } query = qName; + enum { qName, qDrvPath, qStatus } query = qName; enum { sInstalled, sAvailable } source = sInstalled; for (Strings::iterator i = opFlags.begin(); i != opFlags.end(); ++i) if (*i == "--name") query = qName; + else if (*i == "--expr" || *i == "-e") query = qDrvPath; + else if (*i == "--status" || *i == "-s") query = qStatus; else if (*i == "--installed") source = sInstalled; else if (*i == "--available" || *i == "-f") source = sAvailable; else throw UsageError(format("unknown flag `%1%'") % *i); @@ -204,9 +274,11 @@ static void opQuery(EvalState & state, switch (source) { case sInstalled: + queryInstalled(state, drvs); break; case sAvailable: { + if (opArgs.size() < 1) throw UsageError("Nix file expected"); Path nePath = opArgs.front(); opArgs.pop_front(); loadDerivations(state, nePath, drvs); @@ -216,16 +288,36 @@ static void opQuery(EvalState & state, default: abort(); } + if (opArgs.size() != 0) throw UsageError("no arguments expected"); + /* Perform the specified query on the derivations. */ switch (query) { case qName: { - if (opArgs.size() != 0) throw UsageError("no arguments expected"); for (DrvInfos::iterator i = drvs.begin(); i != drvs.end(); ++i) cout << format("%1%\n") % i->second.name; break; } + case qDrvPath: { + for (DrvInfos::iterator i = drvs.begin(); i != drvs.end(); ++i) + cout << format("%1%\n") % i->second.drvPath; + break; + } + + case qStatus: { + DrvInfos installed; + queryInstalled(state, installed); + + for (DrvInfos::iterator i = drvs.begin(); i != drvs.end(); ++i) { + cout << format("%1%%2% %3%\n") + % (installed.find(i->first) != installed.end() ? 'I' : '-') + % (isValidPath(i->second.outPath) ? 'P' : '-') + % i->second.name; + } + break; + } + default: abort(); } } |