lix/src/libstore/build/hook-instance.cc
2020-10-12 17:08:52 +00:00

73 lines
1.9 KiB
C++

#include "globals.hh"
#include "hook-instance.hh"
namespace nix {
HookInstance::HookInstance()
{
debug("starting build hook '%s'", settings.buildHook);
/* Create a pipe to get the output of the child. */
fromHook.create();
/* Create the communication pipes. */
toHook.create();
/* Create a pipe to get the output of the builder. */
builderOut.create();
/* Fork the hook. */
pid = startProcess([&]() {
commonChildInit(fromHook);
if (chdir("/") == -1) throw SysError("changing into /");
/* Dup the communication pipes. */
if (dup2(toHook.readSide.get(), STDIN_FILENO) == -1)
throw SysError("dupping to-hook read side");
/* Use fd 4 for the builder's stdout/stderr. */
if (dup2(builderOut.writeSide.get(), 4) == -1)
throw SysError("dupping builder's stdout/stderr");
/* Hack: pass the read side of that fd to allow build-remote
to read SSH error messages. */
if (dup2(builderOut.readSide.get(), 5) == -1)
throw SysError("dupping builder's stdout/stderr");
Strings args = {
std::string(baseNameOf(settings.buildHook.get())),
std::to_string(verbosity),
};
execv(settings.buildHook.get().c_str(), stringsToCharPtrs(args).data());
throw SysError("executing '%s'", settings.buildHook);
});
pid.setSeparatePG(true);
fromHook.writeSide = -1;
toHook.readSide = -1;
sink = FdSink(toHook.writeSide.get());
std::map<std::string, Config::SettingInfo> settings;
globalConfig.getSettings(settings);
for (auto & setting : settings)
sink << 1 << setting.first << setting.second.value;
sink << 0;
}
HookInstance::~HookInstance()
{
try {
toHook.writeSide = -1;
if (pid != -1) pid.kill();
} catch (...) {
ignoreException();
}
}
}