209 lines
4 KiB
C++
209 lines
4 KiB
C++
#include <iostream>
|
||
#include <cstdlib>
|
||
|
||
#include <setjmp.h>
|
||
|
||
#include <readline/readline.h>
|
||
#include <readline/history.h>
|
||
|
||
#include "shared.hh"
|
||
#include "eval.hh"
|
||
#include "eval-inline.hh"
|
||
#include "store-api.hh"
|
||
#include "common-opts.hh"
|
||
|
||
using namespace std;
|
||
using namespace nix;
|
||
|
||
|
||
string programId = "nix-repl";
|
||
|
||
|
||
struct NixRepl
|
||
{
|
||
string curDir;
|
||
EvalState state;
|
||
|
||
StaticEnv staticEnv;
|
||
Env * env;
|
||
int displ;
|
||
|
||
NixRepl();
|
||
void mainLoop();
|
||
void processLine(string line);
|
||
void addAttrsToScope(Value & attrs);
|
||
void addVarToScope(const Symbol & name, Value * v);
|
||
Expr * parseString(string s);
|
||
void evalString(string s, Value & v);
|
||
};
|
||
|
||
|
||
void printHelp()
|
||
{
|
||
std::cout << "Usage: nix-repl\n";
|
||
}
|
||
|
||
|
||
/* Apparently, the only way to get readline() to return on Ctrl-C
|
||
(SIGINT) is to use siglongjmp(). That's fucked up... */
|
||
static sigjmp_buf sigintJmpBuf;
|
||
|
||
|
||
static void sigintHandler(int signo)
|
||
{
|
||
siglongjmp(sigintJmpBuf, 1);
|
||
}
|
||
|
||
|
||
bool getLine(string & line)
|
||
{
|
||
struct sigaction act, old;
|
||
act.sa_handler = sigintHandler;
|
||
sigfillset(&act.sa_mask);
|
||
act.sa_flags = 0;
|
||
if (sigaction(SIGINT, &act, &old))
|
||
throw SysError("installing handler for SIGINT");
|
||
|
||
if (sigsetjmp(sigintJmpBuf, 1))
|
||
line = "";
|
||
else {
|
||
char * s = readline("nix-repl> ");
|
||
if (!s) return false;
|
||
line = chomp(string(s));
|
||
free(s);
|
||
if (line != "") {
|
||
add_history(line.c_str());
|
||
append_history(1, 0);
|
||
}
|
||
}
|
||
|
||
_isInterrupted = 0;
|
||
|
||
if (sigaction(SIGINT, &old, 0))
|
||
throw SysError("restoring handler for SIGINT");
|
||
|
||
return true;
|
||
}
|
||
|
||
|
||
string removeWhitespace(string s)
|
||
{
|
||
s = chomp(s);
|
||
size_t n = s.find_first_not_of(" \n\r\t");
|
||
if (n != string::npos) s = string(s, n);
|
||
return s;
|
||
}
|
||
|
||
|
||
NixRepl::NixRepl()
|
||
: staticEnv(false, &state.staticBaseEnv)
|
||
{
|
||
curDir = absPath(".");
|
||
|
||
env = &state.allocEnv(32768);
|
||
env->up = &state.baseEnv;
|
||
displ = 0;
|
||
|
||
store = openStore();
|
||
}
|
||
|
||
|
||
void NixRepl::mainLoop()
|
||
{
|
||
std::cerr << "Welcome to Nix version " << NIX_VERSION << ". Type :? for help." << std::endl << std::endl;
|
||
|
||
using_history();
|
||
read_history(0);
|
||
|
||
while (true) {
|
||
string line;
|
||
if (!getLine(line)) break;
|
||
|
||
try {
|
||
processLine(removeWhitespace(line));
|
||
} catch (Error & e) {
|
||
printMsg(lvlError, e.msg());
|
||
}
|
||
|
||
std::cout << std::endl;
|
||
}
|
||
|
||
std::cout << std::endl;
|
||
}
|
||
|
||
|
||
void NixRepl::processLine(string line)
|
||
{
|
||
if (line == "") return;
|
||
|
||
if (string(line, 0, 2) == ":a") {
|
||
Value v;
|
||
evalString(string(line, 2), v);
|
||
addAttrsToScope(v);
|
||
}
|
||
|
||
else if (string(line, 0, 2) == ":l") {
|
||
state.resetFileCache();
|
||
Path path = lookupFileArg(state, removeWhitespace(string(line, 2)));
|
||
Value v, v2;
|
||
state.evalFile(path, v);
|
||
Bindings bindings;
|
||
state.autoCallFunction(bindings, v, v2);
|
||
addAttrsToScope(v2);
|
||
}
|
||
|
||
else if (string(line, 0, 2) == ":t") {
|
||
Value v;
|
||
evalString(string(line, 2), v);
|
||
std::cout << showType(v) << std::endl;
|
||
}
|
||
|
||
else if (string(line, 0, 1) == ":") {
|
||
throw Error(format("unknown command ‘%1%’") % string(line, 0, 2));
|
||
}
|
||
|
||
else {
|
||
Value v;
|
||
evalString(line, v);
|
||
state.strictForceValue(v);
|
||
std::cout << v << std::endl;
|
||
}
|
||
}
|
||
|
||
|
||
void NixRepl::addAttrsToScope(Value & attrs)
|
||
{
|
||
state.forceAttrs(attrs);
|
||
foreach (Bindings::iterator, i, *attrs.attrs)
|
||
addVarToScope(i->name, i->value);
|
||
}
|
||
|
||
|
||
void NixRepl::addVarToScope(const Symbol & name, Value * v)
|
||
{
|
||
staticEnv.vars[name] = displ;
|
||
env->values[displ++] = v;
|
||
}
|
||
|
||
|
||
Expr * NixRepl::parseString(string s)
|
||
{
|
||
Expr * e = state.parseExprFromString(s, curDir, staticEnv);
|
||
return e;
|
||
}
|
||
|
||
|
||
void NixRepl::evalString(string s, Value & v)
|
||
{
|
||
Expr * e = parseString(s);
|
||
e->eval(state, *env, v);
|
||
state.forceValue(v);
|
||
}
|
||
|
||
|
||
void run(nix::Strings args)
|
||
{
|
||
NixRepl repl;
|
||
repl.mainLoop();
|
||
}
|