lix/src/libmain/shared.cc
2014-10-14 11:41:04 +02:00

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#include "config.h"
#include "shared.hh"
#include "globals.hh"
#include "store-api.hh"
#include "util.hh"
#include "misc.hh"
#include <iostream>
#include <cctype>
#include <exception>
#include <algorithm>
#include <sys/time.h>
#include <sys/stat.h>
#include <unistd.h>
#include <signal.h>
namespace nix {
volatile sig_atomic_t blockInt = 0;
static void sigintHandler(int signo)
{
if (!blockInt) {
_isInterrupted = 1;
blockInt = 1;
}
}
static bool gcWarning = true;
void printGCWarning()
{
if (!gcWarning) return;
static bool haveWarned = false;
warnOnce(haveWarned,
"you did not specify --add-root; "
"the result might be removed by the garbage collector");
}
void printMissing(StoreAPI & store, const PathSet & paths)
{
unsigned long long downloadSize, narSize;
PathSet willBuild, willSubstitute, unknown;
queryMissing(store, paths, willBuild, willSubstitute, unknown, downloadSize, narSize);
printMissing(willBuild, willSubstitute, unknown, downloadSize, narSize);
}
void printMissing(const PathSet & willBuild,
const PathSet & willSubstitute, const PathSet & unknown,
unsigned long long downloadSize, unsigned long long narSize)
{
if (!willBuild.empty()) {
printMsg(lvlInfo, format("these derivations will be built:"));
Paths sorted = topoSortPaths(*store, willBuild);
reverse(sorted.begin(), sorted.end());
for (auto & i : sorted)
printMsg(lvlInfo, format(" %1%") % i);
}
if (!willSubstitute.empty()) {
printMsg(lvlInfo, format("these paths will be fetched (%.2f MiB download, %.2f MiB unpacked):")
% (downloadSize / (1024.0 * 1024.0))
% (narSize / (1024.0 * 1024.0)));
for (auto & i : willSubstitute)
printMsg(lvlInfo, format(" %1%") % i);
}
if (!unknown.empty()) {
printMsg(lvlInfo, format("don't know how to build these paths%1%:")
% (settings.readOnlyMode ? " (may be caused by read-only store access)" : ""));
for (auto & i : unknown)
printMsg(lvlInfo, format(" %1%") % i);
}
}
static void setLogType(string lt)
{
if (lt == "pretty") logType = ltPretty;
else if (lt == "escapes") logType = ltEscapes;
else if (lt == "flat") logType = ltFlat;
else throw UsageError("unknown log type");
}
string getArg(const string & opt,
Strings::iterator & i, const Strings::iterator & end)
{
++i;
if (i == end) throw UsageError(format("%1% requires an argument") % opt);
return *i;
}
void detectStackOverflow();
void initNix()
{
/* Turn on buffering for cerr. */
#if HAVE_PUBSETBUF
static char buf[1024];
std::cerr.rdbuf()->pubsetbuf(buf, sizeof(buf));
#endif
std::ios::sync_with_stdio(false);
settings.processEnvironment();
settings.loadConfFile();
/* Catch SIGINT. */
struct sigaction act;
act.sa_handler = sigintHandler;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
if (sigaction(SIGINT, &act, 0))
throw SysError("installing handler for SIGINT");
if (sigaction(SIGTERM, &act, 0))
throw SysError("installing handler for SIGTERM");
if (sigaction(SIGHUP, &act, 0))
throw SysError("installing handler for SIGHUP");
/* Ignore SIGPIPE. */
act.sa_handler = SIG_IGN;
act.sa_flags = 0;
if (sigaction(SIGPIPE, &act, 0))
throw SysError("ignoring SIGPIPE");
/* Reset SIGCHLD to its default. */
act.sa_handler = SIG_DFL;
act.sa_flags = 0;
if (sigaction(SIGCHLD, &act, 0))
throw SysError("resetting SIGCHLD");
/* Register a SIGSEGV handler to detect stack overflows. */
detectStackOverflow();
/* There is no privacy in the Nix system ;-) At least not for
now. In particular, store objects should be readable by
everybody. */
umask(0022);
/* Initialise the PRNG. */
struct timeval tv;
gettimeofday(&tv, 0);
srandom(tv.tv_usec);
if (char *pack = getenv("_NIX_OPTIONS"))
settings.unpack(pack);
}
void parseCmdLine(int argc, char * * argv,
std::function<bool(Strings::iterator & arg, const Strings::iterator & end)> parseArg)
{
/* Put the arguments in a vector. */
Strings args;
argc--; argv++;
while (argc--) args.push_back(*argv++);
/* Process default options. */
for (Strings::iterator i = args.begin(); i != args.end(); ++i) {
string arg = *i;
/* Expand compound dash options (i.e., `-qlf' -> `-q -l -f'). */
if (arg.length() > 2 && arg[0] == '-' && arg[1] != '-' && isalpha(arg[1])) {
*i = (string) "-" + arg[1];
auto next = i; ++next;
for (unsigned int j = 2; j < arg.length(); j++)
if (isalpha(arg[j]))
args.insert(next, (string) "-" + arg[j]);
else {
args.insert(next, string(arg, j));
break;
}
arg = *i;
}
if (arg == "--verbose" || arg == "-v") verbosity = (Verbosity) (verbosity + 1);
else if (arg == "--quiet") verbosity = verbosity > lvlError ? (Verbosity) (verbosity - 1) : lvlError;
else if (arg == "--log-type") {
string s = getArg(arg, i, args.end());
setLogType(s);
}
else if (arg == "--no-build-output" || arg == "-Q")
settings.buildVerbosity = lvlVomit;
else if (arg == "--print-build-trace")
settings.printBuildTrace = true;
else if (arg == "--keep-failed" || arg == "-K")
settings.keepFailed = true;
else if (arg == "--keep-going" || arg == "-k")
settings.keepGoing = true;
else if (arg == "--fallback")
settings.set("build-fallback", "true");
else if (arg == "--max-jobs" || arg == "-j")
settings.set("build-max-jobs", getArg(arg, i, args.end()));
else if (arg == "--cores")
settings.set("build-cores", getArg(arg, i, args.end()));
else if (arg == "--readonly-mode")
settings.readOnlyMode = true;
else if (arg == "--max-silent-time")
settings.set("build-max-silent-time", getArg(arg, i, args.end()));
else if (arg == "--timeout")
settings.set("build-timeout", getArg(arg, i, args.end()));
else if (arg == "--no-build-hook")
settings.useBuildHook = false;
else if (arg == "--show-trace")
settings.showTrace = true;
else if (arg == "--no-gc-warning")
gcWarning = false;
else if (arg == "--option") {
++i; if (i == args.end()) throw UsageError("--option requires two arguments");
string name = *i;
++i; if (i == args.end()) throw UsageError("--option requires two arguments");
string value = *i;
settings.set(name, value);
}
else {
if (!parseArg(i, args.end()))
throw UsageError(format("unrecognised option %1%") % *i);
}
}
settings.update();
}
void printVersion(const string & programName)
{
std::cout << format("%1% (Nix) %2%") % programName % nixVersion << std::endl;
throw Exit();
}
void showManPage(const string & name)
{
restoreSIGPIPE();
execlp("man", "man", name.c_str(), NULL);
throw SysError(format("command man %1% failed") % name.c_str());
}
int handleExceptions(const string & programName, std::function<void()> fun)
{
string error = ANSI_RED "error:" ANSI_NORMAL " ";
try {
try {
fun();
} catch (...) {
/* Subtle: we have to make sure that any `interrupted'
condition is discharged before we reach printMsg()
below, since otherwise it will throw an (uncaught)
exception. */
blockInt = 1; /* ignore further SIGINTs */
_isInterrupted = 0;
throw;
}
} catch (Exit & e) {
return e.status;
} catch (UsageError & e) {
printMsg(lvlError,
format(error + "%1%\nTry %2% --help for more information.")
% e.what() % programName);
return 1;
} catch (BaseError & e) {
printMsg(lvlError, format(error + "%1%%2%") % (settings.showTrace ? e.prefix() : "") % e.msg());
if (e.prefix() != "" && !settings.showTrace)
printMsg(lvlError, "(use --show-trace to show detailed location information)");
return e.status;
} catch (std::bad_alloc & e) {
printMsg(lvlError, error + "out of memory");
return 1;
} catch (std::exception & e) {
printMsg(lvlError, error + e.what());
return 1;
}
return 0;
}
RunPager::RunPager()
{
string pager = getEnv("PAGER");
if (!isatty(STDOUT_FILENO) || pager.empty()) return;
/* Ignore SIGINT. The pager will handle it (and we'll get
SIGPIPE). */
struct sigaction act;
act.sa_handler = SIG_IGN;
act.sa_flags = 0;
sigemptyset(&act.sa_mask);
if (sigaction(SIGINT, &act, 0)) throw SysError("ignoring SIGINT");
restoreSIGPIPE();
Pipe toPager;
toPager.create();
pid = startProcess([&]() {
if (dup2(toPager.readSide, STDIN_FILENO) == -1)
throw SysError("dupping stdin");
if (!getenv("LESS"))
setenv("LESS", "FRSXMK", 1);
execl("/bin/sh", "sh", "-c", pager.c_str(), NULL);
throw SysError(format("executing %1%") % pager);
});
if (dup2(toPager.writeSide, STDOUT_FILENO) == -1)
throw SysError("dupping stdout");
}
RunPager::~RunPager()
{
if (pid != -1) {
std::cout.flush();
close(STDOUT_FILENO);
pid.wait(true);
}
}
}