diff options
Diffstat (limited to 'src/nix.cc')
| -rw-r--r-- | src/nix.cc | 126 |
1 files changed, 85 insertions, 41 deletions
diff --git a/src/nix.cc b/src/nix.cc index cfe879952c27..38643e3d69d5 100644 --- a/src/nix.cc +++ b/src/nix.cc @@ -26,6 +26,7 @@ using namespace std; static string dbRefs = "refs"; static string dbInstPkgs = "pkginst"; static string dbPrebuilts = "prebuilts"; +static string dbNetSources = "netsources"; static string nixSourcesDir; @@ -116,6 +117,65 @@ void enumDB(const string & dbname, DBPairs & contents) } +/* Download object referenced by the given URL into the sources + directory. Return the file name it was downloaded to. */ +string fetchURL(string url) +{ + string filename = baseNameOf(url); + string fullname = nixSourcesDir + "/" + filename; + struct stat st; + if (stat(fullname.c_str(), &st)) { + cerr << "fetching " << url << endl; + /* !!! quoting */ + string shellCmd = + "cd " + nixSourcesDir + " && wget --quiet -N \"" + url + "\""; + int res = system(shellCmd.c_str()); + if (WEXITSTATUS(res) != 0) + throw Error("cannot fetch " + url); + } + return fullname; +} + + +/* Obtain an object with the given hash. If a file with that hash is + known to exist in the local file system (as indicated by the dbRefs + database), we use that. Otherwise, we attempt to fetch it from the + network (using dbNetSources). We verify that the file has the + right hash. */ +string getFile(string hash) +{ + bool checkedNet = false; + + while (1) { + + string fn, url; + + if (queryDB(dbRefs, hash, fn)) { + + /* Verify that the file hasn't changed. !!! race */ + if (hashFile(fn) != hash) + throw Error("file " + fn + " is stale"); + + return fn; + } + + if (checkedNet) + throw Error("consistency problem: file fetched from " + url + + " should have hash " + hash + ", but it doesn't"); + + if (!queryDB(dbNetSources, hash, url)) + throw Error("a file with hash " + hash + " is requested, " + "but it is not known to exist locally or on the network"); + + checkedNet = true; + + fn = fetchURL(url); + + setDB(dbRefs, hash, fn); + } +} + + typedef map<string, string> Params; @@ -124,14 +184,7 @@ void readPkgDescr(const string & hash, { 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 (hashFile(pkgfile) != hash) - throw Error("file " + pkgfile + " is stale"); + pkgfile = getFile(hash); ATerm term = ATreadFromNamedFile(pkgfile.c_str()); if (!term) throw Error("cannot read aterm " + pkgfile); @@ -199,11 +252,7 @@ void fetchDeps(string hash, Environment & env) string file; - if (!queryDB(dbRefs, it->second, file)) - throw Error("unknown file " + it->second); - - if (hashFile(file) != it->second) - throw Error("file " + file + " is stale"); + file = getFile(it->second); env[it->first] = file; } @@ -283,17 +332,18 @@ void installPkg(string hash) /* Try to use a prebuilt. */ string prebuiltHash, prebuiltFile; - if (queryDB(dbPrebuilts, hash, prebuiltHash) && - queryDB(dbRefs, prebuiltHash, prebuiltFile)) - { - cerr << "substituting prebuilt " << prebuiltFile << endl; + if (queryDB(dbPrebuilts, hash, prebuiltHash)) { - if (hashFile(prebuiltFile) != prebuiltHash) { - cerr << "prebuilt " + prebuiltFile + " is stale\n"; + try { + prebuiltFile = getFile(prebuiltHash); + } catch (Error e) { + cerr << "cannot obtain prebuilt (ignoring): " << e.what() << endl; goto build; } + + cerr << "substituting prebuilt " << prebuiltFile << endl; - int res = system(("tar xvfj " + prebuiltFile).c_str()); // !!! escaping + int res = system(("tar xfj " + prebuiltFile + " 1>&2").c_str()); // !!! escaping if (WEXITSTATUS(res) != 0) /* This is a fatal error, because path may now have clobbered. */ @@ -302,6 +352,8 @@ void installPkg(string hash) _exit(0); } + throw Error("no prebuilt available"); + build: /* Fill in the environment. We don't bother freeing the @@ -453,7 +505,7 @@ void exportPkgs(string outDir, } -void regPrebuilt(string pkgHash, string prebuiltHash) +void registerPrebuilt(string pkgHash, string prebuiltHash) { checkHash(pkgHash); checkHash(prebuiltHash); @@ -470,6 +522,14 @@ string registerFile(string filename) } +void registerURL(string hash, string url) +{ + checkHash(hash); + setDB(dbNetSources, hash, url); + /* !!! currently we allow only one network source per hash */ +} + + /* This is primarily used for bootstrapping. */ void registerInstalledPkg(string hash, string path) { @@ -486,6 +546,7 @@ void initDB() openDB(dbRefs, false); openDB(dbInstPkgs, false); openDB(dbPrebuilts, false); + openDB(dbNetSources, false); } @@ -623,25 +684,6 @@ void printGraph(Strings::iterator first, Strings::iterator last) } -/* Download object referenced by the given URL into the sources - directory. Return the file name it was downloaded to. */ -string fetchURL(string url) -{ - string filename = baseNameOf(url); - string fullname = nixSourcesDir + "/" + filename; - struct stat st; - if (stat(fullname.c_str(), &st)) { - /* !!! quoting */ - string shellCmd = - "cd " + nixSourcesDir + " && wget --quiet -N \"" + url + "\""; - int res = system(shellCmd.c_str()); - if (WEXITSTATUS(res) != 0) - throw Error("cannot fetch " + url); - } - return fullname; -} - - void fetch(string id) { string fn; @@ -777,9 +819,11 @@ void run(Strings::iterator argCur, Strings::iterator argEnd) exportPkgs(*argCur, argCur + 1, argEnd); } else if (cmd == "regprebuilt") { if (argc != 2) throw argcError; - regPrebuilt(*argCur, argCur[1]); + registerPrebuilt(*argCur, argCur[1]); } else if (cmd == "regfile") { for_each(argCur, argEnd, registerFile); + } else if (cmd == "regurl") { + registerURL(argCur[0], argCur[1]); } else if (cmd == "reginst") { if (argc != 2) throw argcError; registerInstalledPkg(*argCur, argCur[1]); |