lix/src/nix.cc
Eelco Dolstra 34fcf5fa0c * Started integrating the new evaluation model into Nix.
* Cleaned up command-line syntax.
2003-06-17 21:12:58 +00:00

177 lines
4.2 KiB
C++

#include <iostream>
#include "config.h"
#include "globals.hh"
#include "values.hh"
#include "eval.hh"
typedef void (* Operation) (Strings opFlags, Strings opArgs);
/* Parse a supposed value argument. This can be a hash (the simple
case), a symbolic name (in which case we do a lookup to obtain the
hash), or a file name (which we import to obtain the hash). Note
that in order to disambiguate between symbolic names and file
names, a file name should contain at least one `/'. */
Hash parseValueArg(string s)
{
try {
return parseHash(s);
} catch (BadRefError e) { };
if (s.find('/') != string::npos) {
return addValue(s);
} else {
throw Error("not implemented");
}
}
/* Evaluate values. */
static void opEvaluate(Strings opFlags, Strings opArgs)
{
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
it != opArgs.end(); it++)
{
Hash hash = parseValueArg(*it);
Expr e = ATmake("Deref(Hash(<str>))", ((string) hash).c_str());
cerr << printExpr(evalValue(e)) << endl;
}
}
static void opDelete(Strings opFlags, Strings opArgs)
{
cerr << "delete!\n";
}
/* Add values to the Nix values directory and print the hashes of
those values. */
static void opAdd(Strings opFlags, Strings opArgs)
{
if (!opFlags.empty()) throw UsageError("unknown flag");
for (Strings::iterator it = opArgs.begin();
it != opArgs.end(); it++)
cout << (string) addValue(*it) << endl;
}
/* Initialise the Nix databases. */
static void opInit(Strings opFlags, Strings opArgs)
{
if (!opFlags.empty()) throw UsageError("unknown flag");
if (!opArgs.empty())
throw UsageError("--init does not have arguments");
initDB();
}
/* Nix syntax:
nix [OPTIONS...] [ARGUMENTS...]
Operations:
--evaluate / -e: evaluate values
--delete / -d: delete values
--query / -q: query stored values
--add: add values
--verify: verify Nix structures
--dump: dump a value
--init: initialise the Nix database
--version: output version information
--help: display help
Operations that work on values accept the hash code of a value, the
symbolic name of a value, or a file name of a external value that
will be added prior to the operation.
Query suboptions:
Selection:
--all / -a: query all stored values, otherwise given values
Information:
--info / -i: general value information
Options:
--verbose / -v: verbose operation
*/
/* Initialize, process arguments, and dispatch to the right
operation. */
void run(Strings::iterator argCur, Strings::iterator argEnd)
{
Strings opFlags, opArgs;
Operation op = 0;
/* Setup Nix paths. */
nixValues = NIX_VALUES_DIR;
nixLogDir = NIX_LOG_DIR;
nixDB = (string) NIX_STATE_DIR + "/nixstate.db";
/* Scan the arguments; find the operation, set global flags, put
all other flags in a list, and put all other arguments in
another list. */
while (argCur != argEnd) {
string arg = *argCur++;
Operation oldOp = op;
if (arg == "--evaluate" || arg == "-e")
op = opEvaluate;
else if (arg == "--delete" || arg == "-d")
op = opDelete;
else if (arg == "--add")
op = opAdd;
else if (arg == "--init")
op = opInit;
else if (arg[0] == '-')
opFlags.push_back(arg);
else
opArgs.push_back(arg);
if (oldOp && oldOp != op)
throw UsageError("only one operation may be specified");
}
if (!op) throw UsageError("no operation specified");
op(opFlags, opArgs);
}
int main(int argc, char * * argv)
{
/* ATerm setup. */
ATerm bottomOfStack;
ATinit(argc, argv, &bottomOfStack);
try {
Strings args;
while (argc--) args.push_back(*argv++);
run(args.begin() + 1, args.end());
} catch (UsageError & e) {
cerr << "error: " << e.what() << endl
<< "Try `nix --help' for more information.\n";
return 1;
} catch (exception & e) {
cerr << "error: " << e.what() << endl;
return 1;
}
return 0;
}