diff options
Diffstat (limited to 'src/fix.cc')
| -rw-r--r-- | src/fix.cc | 196 |
1 files changed, 130 insertions, 66 deletions
diff --git a/src/fix.cc b/src/fix.cc index 0d3ae9bff868..052c1d4c9103 100644 --- a/src/fix.cc +++ b/src/fix.cc @@ -16,6 +16,9 @@ static string nixDescriptorDir; static string nixSourcesDir; +static bool verbose = false; + + /* Mapping of Fix file names to the hashes of the resulting Nix descriptors. */ typedef map<string, string> DescriptorMap; @@ -23,10 +26,6 @@ typedef map<string, string> DescriptorMap; /* Forward declarations. */ -string instantiateDescriptor(string filename, - DescriptorMap & done); - - void registerFile(string filename) { int res = system(("nix regfile " + filename).c_str()); @@ -74,79 +73,136 @@ string fetchURL(string url) } -/* Term evaluation functions. */ - -string evaluateStr(ATerm e) +Error badTerm(const string & msg, ATerm e) { - char * s; - if (ATmatch(e, "<str>", &s)) - return s; - else throw Error("invalid string expression"); + char * s = ATwriteToString(e); + return Error(msg + ", in `" + s + "'"); } -ATerm evaluateBool(ATerm e) +/* Term evaluation. */ + +typedef map<string, ATerm> BindingsMap; + +struct EvalContext { - if (ATmatch(e, "True") || ATmatch(e, "False")) - return e; - else throw Error("invalid boolean expression"); -} + string dir; + DescriptorMap * done; + BindingsMap * vars; +}; + +ATerm evaluate(ATerm e, EvalContext ctx); +string instantiateDescriptor(string filename, EvalContext ctx); -string evaluateFile(ATerm e, string dir) + +string evaluateStr(ATerm e, EvalContext ctx) { + e = evaluate(e, ctx); char * s; - ATerm t; - if (ATmatch(e, "<str>", &s)) { - checkHash(s); + if (ATmatch(e, "Str(<str>)", &s)) return s; - } else if (ATmatch(e, "Url(<term>)", &t)) { - string url = evaluateStr(t); - string filename = fetchURL(url); - registerFile(filename); - return hashFile(filename); - } else if (ATmatch(e, "Local(<term>)", &t)) { - string filename = absPath(evaluateStr(t), dir); /* !!! */ - string cmd = "cp -p " + filename + " " + nixSourcesDir; - int res = system(cmd.c_str()); - if (WEXITSTATUS(res) != 0) - throw Error("cannot copy " + filename); - registerFile(nixSourcesDir + "/" + baseNameOf(filename)); - return hashFile(filename); - } else throw Error("invalid file expression"); + else throw badTerm("string value expected", e); } -string evaluatePkg(ATerm e, string dir, DescriptorMap & done) +bool evaluateBool(ATerm e, EvalContext ctx) { - char * s; - ATerm t; - if (ATmatch(e, "<str>", &s)) { - checkHash(s); - return s; - } else if (ATmatch(e, "Fix(<term>)", &t)) { - string filename = absPath(evaluateStr(t), dir); /* !!! */ - return instantiateDescriptor(filename, done); - } else throw Error("invalid pkg expression"); + e = evaluate(e, ctx); + if (ATmatch(e, "Bool(True)")) + return true; + else if (ATmatch(e, "Bool(False)")) + return false; + else throw badTerm("boolean value expected", e); } -ATerm evaluate(ATerm e, string dir, DescriptorMap & done) +ATerm evaluate(ATerm e, EvalContext ctx) { - ATerm t; - if (ATmatch(e, "Str(<term>)", &t)) - return ATmake("Str(<str>)", evaluateStr(t).c_str()); - else if (ATmatch(e, "Bool(<term>)", &t)) - return ATmake("Bool(<term>)", evaluateBool(t)); - else if (ATmatch(e, "File(<term>)", &t)) - return ATmake("File(<str>)", evaluateFile(t, dir).c_str()); - else if (ATmatch(e, "Pkg(<term>)", &t)) - return ATmake("Pkg(<str>)", evaluatePkg(t, dir, done).c_str()); - else throw Error("invalid expression type"); -} + char * s; + ATerm e2; + ATerm eCond, eTrue, eFalse; + /* Check for normal forms first. */ -typedef map<string, ATerm> BindingsMap; + if (ATmatch(e, "Str(<str>)", &s) || + ATmatch(e, "Bool(True)") || ATmatch(e, "Bool(False)")) + return e; + + else if ( + ATmatch(e, "Pkg(<str>)", &s) || + ATmatch(e, "File(<str>)", &s)) + { + checkHash(s); + return e; + } + + /* Short-hands. */ + + else if (ATmatch(e, "<str>", &s)) + return ATmake("Str(<str>)", s); + + else if (ATmatch(e, "True", &s)) + return ATmake("Bool(True)", s); + + else if (ATmatch(e, "False", &s)) + return ATmake("Bool(False)", s); + + /* Functions. */ + + /* `Var' looks up a variable. */ + else if (ATmatch(e, "Var(<str>)", &s)) { + string name(s); + ATerm e2 = (*ctx.vars)[name]; + if (!e2) throw Error("undefined variable " + name); + return evaluate(e2, ctx); /* !!! update binding */ + } + + /* `Fix' recursively instantiates a Fix descriptor, returning the + hash of the generated Nix descriptor. */ + else if (ATmatch(e, "Fix(<term>)", &e2)) { + string filename = absPath(evaluateStr(e2, ctx), ctx.dir); /* !!! */ + return ATmake("Pkg(<str>)", + instantiateDescriptor(filename, ctx).c_str()); + } + + /* `Source' copies the specified file to nixSourcesDir, registers + it with Nix, and returns the hash of the file. */ + else if (ATmatch(e, "Source(<term>)", &e2)) { + string source = absPath(evaluateStr(e2, ctx), ctx.dir); /* !!! */ + string target = nixSourcesDir + "/" + baseNameOf(source); + + // Don't copy if filename is already in nixSourcesDir. + if (source != target) { + if (verbose) + cerr << "copying source " << source << endl; + string cmd = "cp -p " + source + " " + target; + int res = system(cmd.c_str()); + if (WEXITSTATUS(res) != 0) + throw Error("cannot copy " + source + " to " + target); + } + + registerFile(target); + return ATmake("File(<str>)", hashFile(target).c_str()); + } + + /* `Url' fetches a file from the network, caching it in + nixSourcesDir and returning the file name. */ + else if (ATmatch(e, "Url(<term>)", &e2)) { + string url = evaluateStr(e2, ctx); + if (verbose) + cerr << "fetching " << url << endl; + string filename = fetchURL(url); + return ATmake("Str(<str>)", filename.c_str()); + } + + /* `If' provides conditional evaluation. */ + else if (ATmatch(e, "If(<term>, <term>, <term>)", + &eCond, &eTrue, &eFalse)) + return evaluate(evaluateBool(eCond, ctx) ? eTrue : eFalse, ctx); + + else throw badTerm("invalid expression", e); +} string getStringFromMap(BindingsMap & bindingsMap, @@ -164,15 +220,14 @@ string getStringFromMap(BindingsMap & bindingsMap, /* Instantiate a Fix descriptors into a Nix descriptor, recursively instantiating referenced descriptors as well. */ -string instantiateDescriptor(string filename, - DescriptorMap & done) +string instantiateDescriptor(string filename, EvalContext ctx) { /* Already done? */ - DescriptorMap::iterator isInMap = done.find(filename); - if (isInMap != done.end()) return isInMap->second; + DescriptorMap::iterator isInMap = ctx.done->find(filename); + if (isInMap != ctx.done->end()) return isInMap->second; /* No. */ - string dir = dirOf(filename); + ctx.dir = dirOf(filename); /* Read the Fix descriptor as an ATerm. */ ATerm inTerm = ATreadFromNamedFile(filename.c_str()); @@ -184,6 +239,7 @@ string instantiateDescriptor(string filename, /* Iterate over the bindings and evaluate them to normal form. */ BindingsMap bindingsMap; /* the normal forms */ + ctx.vars = &bindingsMap; char * cname; ATerm value; @@ -191,7 +247,7 @@ string instantiateDescriptor(string filename, &cname, &value, &bindings)) { string name(cname); - ATerm e = evaluate(value, dir, done); + ATerm e = evaluate(value, ctx); bindingsMap[name] = e; } @@ -229,7 +285,10 @@ string instantiateDescriptor(string filename, /* Register it with Nix. */ registerFile(outFilename); - done[filename] = outHash; + if (verbose) + cerr << "instantiated " << outHash << " from " << filename << endl; + + (*ctx.done)[filename] = outHash; return outHash; } @@ -239,11 +298,14 @@ void instantiateDescriptors(Strings filenames) { DescriptorMap done; + EvalContext ctx; + ctx.done = &done; + for (Strings::iterator it = filenames.begin(); it != filenames.end(); it++) { string filename = absPath(*it); - cout << instantiateDescriptor(filename, done) << endl; + cout << instantiateDescriptor(filename, ctx) << endl; } } @@ -274,7 +336,9 @@ void run(Strings::iterator argCur, Strings::iterator argEnd) if (arg == "-h" || arg == "--help") { printUsage(); return; - } if (arg == "--instantiate" || arg == "-i") { + } else if (arg == "-v" || arg == "--verbose") { + verbose = true; + } else if (arg == "--instantiate" || arg == "-i") { command = cmdInstantiate; } else if (arg[0] == '-') throw UsageError("invalid option `" + arg + "'"); |