lix/src/nix-instantiate/main.cc
Eelco Dolstra 4661282fde * `nix-instantiate ... --arg NAME VALUE': allow arguments to be passed
to functions from the command line.
* nix-build: started removing backticks.
2006-07-28 16:03:28 +00:00

159 lines
4.4 KiB
C++

#include <map>
#include <iostream>
#include "globals.hh"
#include "build.hh"
#include "gc.hh"
#include "shared.hh"
#include "eval.hh"
#include "parser.hh"
#include "nixexpr-ast.hh"
#include "get-drvs.hh"
#include "attr-path.hh"
#include "help.txt.hh"
void printHelp()
{
cout << string((char *) helpText, sizeof helpText);
}
static Expr parseStdin(EvalState & state)
{
startNest(nest, lvlTalkative, format("parsing standard input"));
string s, s2;
while (getline(cin, s2)) s += s2 + "\n";
return parseExprFromString(state, s, absPath("."));
}
static Path gcRoot;
static int rootNr = 0;
static bool indirectRoot = false;
static void printResult(EvalState & state, Expr e,
bool evalOnly, bool printArgs, const ATermMap & autoArgs)
{
if (evalOnly)
cout << format("%1%\n") % e;
else if (printArgs) {
ATermList formals;
ATerm body, pos;
if (matchFunction(e, formals, body, pos)) {
for (ATermIterator i(formals); i; ++i) {
Expr name; ValidValues valids; ATerm dummy;
if (!matchFormal(*i, name, valids, dummy)) abort();
cout << format("%1%: ") % aterm2String(name);
ATermList valids2;
if (matchValidValues(valids, valids2)) {
for (ATermIterator j(valids2); j; ++j) {
Expr e = evalExpr(state, *j);
cout << format("%1% ") % showValue(e);
}
}
cout << format("\n");
}
} else
printMsg(lvlError, "warning: expression does not evaluate to a function");
}
else {
DrvInfos drvs;
getDerivations(state, e, "", autoArgs, drvs);
for (DrvInfos::iterator i = drvs.begin(); i != drvs.end(); ++i) {
Path drvPath = i->queryDrvPath(state);
if (gcRoot == "")
printGCWarning();
else
drvPath = addPermRoot(drvPath,
makeRootName(gcRoot, rootNr),
indirectRoot);
cout << format("%1%\n") % drvPath;
}
}
}
void run(Strings args)
{
EvalState state;
Strings files;
bool readStdin = false;
bool evalOnly = false;
bool parseOnly = false;
bool printArgs = false;
string attrPath;
ATermMap autoArgs(128);
for (Strings::iterator i = args.begin();
i != args.end(); )
{
string arg = *i++;
if (arg == "-")
readStdin = true;
else if (arg == "--eval-only") {
readOnlyMode = true;
evalOnly = true;
}
else if (arg == "--parse-only") {
readOnlyMode = true;
parseOnly = evalOnly = true;
}
else if (arg == "--print-args") {
readOnlyMode = true;
printArgs = true;
}
else if (arg == "--attr" || arg == "-A") {
if (i == args.end())
throw UsageError("`--attr' requires an argument");
attrPath = *i++;
}
else if (arg == "--arg") {
if (i == args.end())
throw UsageError("`--arg' requires two arguments");
string name = *i++;
if (i == args.end())
throw UsageError("`--arg' requires two arguments");
Expr value = parseExprFromString(state, *i++, absPath("."));
autoArgs.set(toATerm(name), value);
}
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] == '-')
throw UsageError(format("unknown flag `%1%'") % arg);
else
files.push_back(arg);
}
openDB();
if (readStdin) {
Expr e = findAlongAttrPath(state, attrPath, parseStdin(state));
if (!parseOnly) e = evalExpr(state, e);
printResult(state, e, evalOnly, printArgs, autoArgs);
}
for (Strings::iterator i = files.begin();
i != files.end(); i++)
{
Path path = absPath(*i);
Expr e = findAlongAttrPath(state, attrPath,
parseExprFromFile(state, path));
if (!parseOnly) e = evalExpr(state, e);
printResult(state, e, evalOnly, printArgs, autoArgs);
}
printEvalStats(state);
}
string programId = "nix-instantiate";