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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2019, 2020 Oleg Pykhalov <go.wigust@gmail.com>
;;; Copyright © 2020 Peng Mei Yu <i@pengmeiyu.com>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gnu services nix)
  #:use-module (gnu packages admin)
  #:use-module (gnu packages package-management)
  #:use-module (gnu services base)
  #:use-module (gnu services configuration)
  #:use-module (gnu services shepherd)
  #:use-module (gnu services web)
  #:use-module (gnu services)
  #:use-module (gnu system shadow)
  #:use-module (guix gexp)
  #:use-module (guix packages)
  #:use-module (guix records)
  #:use-module (guix store)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 match)
  #:use-module (ice-9 format)
  #:use-module (guix modules)
  #:export (nix-service-type

            nix-configuration
            nix-configuration?))

;;; Commentary:
;;;
;;; This module provides a service definition for the Nix daemon.
;;;
;;; Code:

(define-record-type* <nix-configuration>
  nix-configuration make-nix-configuration
  nix-configuration?
  (package             nix-configuration-package ;package
                       (default nix))
  (sandbox             nix-configuration-sandbox ;boolean
                       (default #t))
  (build-sandbox-items nix-configuration-build-sandbox-items ;list of strings
                       (default '()))
  (extra-config        nix-configuration-extra-config ;list of strings
                       (default '()))
  (extra-options       nix-configuration-extra-options ;list of strings
                       (default '())))

;; Copied from gnu/services/base.scm
(define* (nix-build-accounts count #:key
                             (group "nixbld")
                             (shadow shadow))
  "Return a list of COUNT user accounts for Nix build users with the given
GID."
  (unfold (cut > <> count)
          (lambda (n)
            (user-account
             (name (format #f "nixbld~2,'0d" n))
             (system? #t)
             (group group)
             (supplementary-groups (list group "kvm"))
             (comment (format #f "Nix Build User ~2d" n))
             (home-directory "/var/empty")
             (shell (file-append shadow "/sbin/nologin"))))
          1+
          1))
(define (nix-accounts _)
  "Return the user accounts and user groups."
  (cons (user-group
         (name "nixbld")
         (system? #t)

         ;; Use a fixed GID so that we can create the store with the right
         ;; owner.
         (id 40000))
        (nix-build-accounts 10 #:group "nixbld")))

(define (nix-activation _)
  ;; Return the activation gexp.
  #~(begin
      (use-modules (guix build utils)
                   (srfi srfi-26))
      (for-each (cut mkdir-p <>) '("/nix/store" "/nix/var/log"
                                   "/nix/var/nix/gcroots/per-user"
                                   "/nix/var/nix/profiles/per-user"))
      (chown "/nix/store"
             (passwd:uid (getpw "root")) (group:gid (getpw "nixbld01")))
      (chmod "/nix/store" #o775)
      (for-each (cut chmod <> #o777) '("/nix/var/nix/profiles"
                                       "/nix/var/nix/profiles/per-user"))))

(define nix-service-etc
  (match-lambda
    (($ <nix-configuration> package sandbox build-sandbox-items extra-config)
     (let ((ref-file (references-file package)))
       `(("nix/nix.conf"
          ,(computed-file
            "nix.conf"
            #~(begin
                (use-modules (srfi srfi-26)
                             (ice-9 format))
                (with-output-to-file #$output
                  (lambda _
                    (define internal-sandbox-paths
                      (call-with-input-file #$ref-file read))

                    (format #t "sandbox = ~a~%" (if #$sandbox "true" "false"))
                    ;; config.nix captures store file names.
                    (format #t "build-sandbox-paths = ~{~a ~}~%"
                            (append internal-sandbox-paths
                                    '#$build-sandbox-items))
                    (for-each (cut display <>) '#$extra-config)))))))))))

(define nix-shepherd-service
  ;; Return a <shepherd-service> for Nix.
  (match-lambda
    (($ <nix-configuration> package _ _ _ extra-options)
     (list
      (shepherd-service
       (provision '(nix-daemon))
       (documentation "Run nix-daemon.")
       (requirement '())
       (start #~(make-forkexec-constructor
                 (list (string-append #$package "/bin/nix-daemon")
                       #$@extra-options)))
       (respawn? #f)
       (stop #~(make-kill-destructor)))))))

(define nix-service-type
  (service-type
   (name 'nix)
   (extensions
    (list (service-extension shepherd-root-service-type nix-shepherd-service)
          (service-extension account-service-type nix-accounts)
          (service-extension activation-service-type nix-activation)
          (service-extension etc-service-type nix-service-etc)
          (service-extension profile-service-type
                             (compose list nix-configuration-package))))
   (description "Run the Nix daemon.")
   (default-value (nix-configuration))))

;;; nix.scm ends here
generated by cgit
st.st_size); if (result != st.st_size) throw SysError("reading symlink target"); target[st.st_size] = '\0'; int err = symlinkat(target, destinationroot, destination.c_str()); if (err != 0) throw SysError(format("creating symlink `%1%'") % destination); fchownat(destinationroot, destination.c_str(), st.st_uid, st.st_gid, AT_SYMLINK_NOFOLLOW); } else if (S_ISDIR(st.st_mode)) { int err = mkdirat(destinationroot, destination.c_str(), 0755); if (err != 0) throw SysError(format("creating directory `%1%'") % destination); AutoCloseFD destinationFd = openat(destinationroot, destination.c_str(), O_CLOEXEC | O_RDONLY | O_DIRECTORY); if (err != 0) throw SysError(format("opening directory `%1%'") % destination); AutoCloseFD sourceFd = openat(sourceroot, source.c_str(), O_CLOEXEC | O_NOFOLLOW | O_RDONLY); if (sourceFd == -1) throw SysError(format("opening `%1%'") % source); if (deleteSource && !(st.st_mode & S_IWUSR)) { /* Ensure the directory writable so files within it can be deleted. */ if (fchmod(sourceFd, st.st_mode | S_IWUSR) == -1) throw SysError(format("making `%1%' directory writable") % source); } for (auto & i : readDirectory(sourceFd)) copyFileRecursively((int)sourceFd, i.name, (int)destinationFd, i.name, deleteSource); fchown(destinationFd, st.st_uid, st.st_gid); } else throw Error(format("refusing to copy irregular file `%1%'") % source); if (deleteSource) unlinkat(sourceroot, source.c_str(), S_ISDIR(st.st_mode) ? AT_REMOVEDIR : 0); } void copyFileRecursively(const Path &source, const Path &destination, bool deleteSource) { copyFileRecursively(AT_FDCWD, source, AT_FDCWD, destination, deleteSource); } static Path tempName(Path tmpRoot, const Path & prefix, bool includePid, int & counter) { tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR", "/tmp") : tmpRoot, true); if (includePid) return (format("%1%/%2%-%3%-%4%") % tmpRoot % prefix % getpid() % counter++).str(); else return (format("%1%/%2%-%3%") % tmpRoot % prefix % counter++).str(); } Path createTempDir(const Path & tmpRoot, const Path & prefix, bool includePid, bool useGlobalCounter, mode_t mode) { static int globalCounter = 0; int localCounter = 0; int & counter(useGlobalCounter ? globalCounter : localCounter); while (1) { checkInterrupt(); Path tmpDir = tempName(tmpRoot, prefix, includePid, counter); if (mkdir(tmpDir.c_str(), mode) == 0) { /* Explicitly set the group of the directory. This is to work around around problems caused by BSD's group ownership semantics (directories inherit the group of the parent). For instance, the group of /tmp on FreeBSD is "wheel", so all directories created in /tmp will be owned by "wheel"; but if the user is not in "wheel", then "tar" will fail to unpack archives that have the setgid bit set on directories. */ if (chown(tmpDir.c_str(), (uid_t) -1, getegid()) != 0) throw SysError(format("setting group of directory `%1%'") % tmpDir); return tmpDir; } if (errno != EEXIST) throw SysError(format("creating directory `%1%'") % tmpDir); } } Paths createDirs(const Path & path) { Paths created; if (path == "/") return created; struct stat st; if (lstat(path.c_str(), &st) == -1) { created = createDirs(dirOf(path)); if (mkdir(path.c_str(), 0777) == -1 && errno != EEXIST) throw SysError(format("creating directory `%1%'") % path); st = lstat(path); created.push_back(path); } if (S_ISLNK(st.st_mode) && stat(path.c_str(), &st) == -1) throw SysError(format("statting symlink `%1%'") % path); if (!S_ISDIR(st.st_mode)) throw Error(format("`%1%' is not a directory") % path); return created; } void createSymlink(const Path & target, const Path & link) { if (symlink(target.c_str(), link.c_str())) throw SysError(format("creating symlink from `%1%' to `%2%'") % link % target); } LogType logType = ltPretty; Verbosity verbosity = lvlInfo; static int nestingLevel = 0; Nest::Nest() { nest = false; } Nest::~Nest() { close(); } static string escVerbosity(Verbosity level) { return std::to_string((int) level); } void Nest::open(Verbosity level, const FormatOrString & fs) { if (level <= verbosity) { if (logType == ltEscapes) std::cerr << "\033[" << escVerbosity(level) << "p" << fs.s << "\n"; else printMsg_(level, fs); nest = true; nestingLevel++; } } void Nest::close() { if (nest) { nestingLevel--; if (logType == ltEscapes) std::cerr << "\033[q"; nest = false; } } void printMsg_(Verbosity level, const FormatOrString & fs) { checkInterrupt(); if (level > verbosity) return; string prefix; if (logType == ltPretty) for (int i = 0; i < nestingLevel; i++) prefix += "| "; else if (logType == ltEscapes && level != lvlInfo) prefix = "\033[" + escVerbosity(level) + "s"; string s = (format("%1%%2%\n") % prefix % fs.s).str(); writeToStderr(s); } void warnOnce(bool & haveWarned, const FormatOrString & fs) { if (!haveWarned) { printMsg(lvlError, format("warning: %1%") % fs.s); haveWarned = true; } } void writeToStderr(const string & s) { try { if (_writeToStderr) _writeToStderr((const unsigned char *) s.data(), s.size()); else writeFull(STDERR_FILENO, s); } catch (SysError & e) { /* Ignore failing writes to stderr if we're in an exception handler, otherwise throw an exception. We need to ignore write errors in exception handlers to ensure that cleanup code runs to completion if the other side of stderr has been closed unexpectedly. */ if (!std::uncaught_exception()) throw; } } void (*_writeToStderr) (const unsigned char * buf, size_t count) = 0; void readFull(int fd, unsigned char * buf, size_t count) { while (count) { checkInterrupt(); ssize_t res = read(fd, (char *) buf, count); if (res == -1) { if (errno == EINTR) continue; throw SysError("reading from file"); } if (res == 0) throw EndOfFile("unexpected end-of-file"); count -= res; buf += res; } } void writeFull(int fd, const unsigned char * buf, size_t count) { while (count) { checkInterrupt(); ssize_t res = write(fd, (char *) buf, count); if (res == -1) { if (errno == EINTR) continue; throw SysError("writing to file"); } count -= res; buf += res; } } void writeFull(int fd, const string & s) { writeFull(fd, (const unsigned char *) s.data(), s.size()); } string drainFD(int fd) { string result; unsigned char buffer[4096]; while (1) { checkInterrupt(); ssize_t rd = read(fd, buffer, sizeof buffer); if (rd == -1) { if (errno != EINTR) throw SysError("reading from file"); } else if (rd == 0) break; else result.append((char *) buffer, rd); } return result; } ////////////////////////////////////////////////////////////////////// AutoDelete::AutoDelete(const string & p, bool recursive) : path(p) { del = true; this->recursive = recursive; } AutoDelete::~AutoDelete() { try { if (del) { if (recursive) deletePath(path); else { if (remove(path.c_str()) == -1) throw SysError(format("cannot unlink `%1%'") % path); } } } catch (...) { ignoreException(); } } void AutoDelete::cancel() { del = false; } ////////////////////////////////////////////////////////////////////// AutoCloseFD::AutoCloseFD() { fd = -1; } AutoCloseFD::AutoCloseFD(int fd) { this->fd = fd; } AutoCloseFD::AutoCloseFD(const AutoCloseFD & fd) { /* Copying an AutoCloseFD isn't allowed (who should get to close it?). But as an edge case, allow copying of closed AutoCloseFDs. This is necessary due to tiresome reasons involving copy constructor use on default object values in STL containers (like when you do `map[value]' where value isn't in the map yet). */ this->fd = fd.fd; if (this->fd != -1) abort(); } AutoCloseFD::~AutoCloseFD() { try { close(); } catch (...) { ignoreException(); } } void AutoCloseFD::operator =(int fd) { if (this->fd != fd) close(); this->fd = fd; } AutoCloseFD::operator int() const { return fd; } void AutoCloseFD::close() { if (fd != -1) { if (::close(fd) == -1) /* This should never happen. */ throw SysError(format("closing file descriptor %1%") % fd); fd = -1; } } bool AutoCloseFD::isOpen() { return fd != -1; } /* Pass responsibility for closing this fd to the caller. */ int AutoCloseFD::borrow() { int oldFD = fd; fd = -1; return oldFD; } void Pipe::create() { int fds[2]; if (pipe(fds) != 0) throw SysError("creating pipe"); readSide = fds[0]; writeSide = fds[1]; closeOnExec(readSide); closeOnExec(writeSide); } ////////////////////////////////////////////////////////////////////// AutoCloseDir::AutoCloseDir() { dir = 0; } AutoCloseDir::AutoCloseDir(DIR * dir) { this->dir = dir; } AutoCloseDir::~AutoCloseDir() { close(); } void AutoCloseDir::operator =(DIR * dir) { this->dir = dir; } AutoCloseDir::operator DIR *() { return dir; } void AutoCloseDir::close() { if (dir) { closedir(dir); dir = 0; } } ////////////////////////////////////////////////////////////////////// Pid::Pid() : pid(-1), separatePG(false), killSignal(SIGKILL) { } Pid::Pid(pid_t pid) : pid(pid), separatePG(false), killSignal(SIGKILL) { } Pid::~Pid() { kill(); } void Pid::operator =(pid_t pid) { if (this->pid != pid) kill(); this->pid = pid; killSignal = SIGKILL; // reset signal to default } Pid::operator pid_t() { return pid; } void Pid::kill(bool quiet) { if (pid == -1 || pid == 0) return; if (!quiet) printMsg(lvlError, format("killing process %1%") % pid); /* Send the requested signal to the child. If it has its own process group, send the signal to every process in the child process group (which hopefully includes *all* its children). */ if (::kill(separatePG ? -pid : pid, killSignal) != 0) printMsg(lvlError, (SysError(format("killing process %1%") % pid).msg())); /* Wait until the child dies, disregarding the exit status. */ int status; while (waitpid(pid, &status, 0) == -1) { checkInterrupt(); if (errno != EINTR) { printMsg(lvlError, (SysError(format("waiting for process %1%") % pid).msg())); break; } } pid = -1; } int Pid::wait(bool block) { assert(pid != -1); while (1) { int status; int res = waitpid(pid, &status, block ? 0 : WNOHANG); if (res == pid) { pid = -1; return status; } if (res == 0 && !block) return -1; if (errno != EINTR) throw SysError("cannot get child exit status"); checkInterrupt(); } } void Pid::setSeparatePG(bool separatePG) { this->separatePG = separatePG; } void Pid::setKillSignal(int signal) { this->killSignal = signal; } void killUser(uid_t uid) { debug(format("killing all processes running under uid `%1%'") % uid); assert(uid != 0); /* just to be safe... */ /* The system call kill(-1, sig) sends the signal `sig' to all users to which the current process can send signals. So we fork a process, switch to uid, and send a mass kill. */ Pid pid = startProcess([&]() { if (setuid(uid) == -1) throw SysError("setting uid"); while (true) { #ifdef __APPLE__ /* OSX's kill syscall takes a third parameter that, among other things, determines if kill(-1, signo) affects the calling process. In the OSX libc, it's set to true, which means "follow POSIX", which we don't want here */ if (syscall(SYS_kill, -1, SIGKILL, false) == 0) break; #elif __GNU__ /* Killing all a user's processes using PID=-1 does currently not work on the Hurd. */ if (kill(getpid(), SIGKILL) == 0) break; #else if (kill(-1, SIGKILL) == 0) break; #endif if (errno == ESRCH) break; /* no more processes */ if (errno != EINTR) throw SysError(format("cannot kill processes for uid `%1%'") % uid); } _exit(0); }); int status = pid.wait(true); #if __GNU__ /* When the child killed itself, status = SIGKILL. */ if (status == SIGKILL) return; #endif if (status != 0) throw Error(format("cannot kill processes for uid `%1%': %2%") % uid % statusToString(status)); /* !!! We should really do some check to make sure that there are no processes left running under `uid', but there is no portable way to do so (I think). The most reliable way may be `ps -eo uid | grep -q $uid'. */ } ////////////////////////////////////////////////////////////////////// pid_t startProcess(std::function<void()> fun, bool dieWithParent, const string & errorPrefix, bool runExitHandlers) { pid_t pid = fork(); if (pid == -1) throw SysError("unable to fork"); if (pid == 0) { _writeToStderr = 0; try { #if __linux__ if (dieWithParent && prctl(PR_SET_PDEATHSIG, SIGKILL) == -1) throw SysError("setting death signal"); #endif restoreAffinity(); fun(); } catch (std::exception & e) { try { std::cerr << errorPrefix << e.what() << "\n"; } catch (...) { } } catch (...) { } if (runExitHandlers) exit(1); else _exit(1); } return pid; } std::vector<char *> stringsToCharPtrs(const Strings & ss) { std::vector<char *> res; for (auto & s : ss) res.push_back((char *) s.c_str()); res.push_back(0); return res; } string runProgram(Path program, bool searchPath, const Strings & args) { checkInterrupt(); /* Create a pipe. */ Pipe pipe; pipe.create(); /* Fork. */ Pid pid = startProcess([&]() { if (dup2(pipe.writeSide, STDOUT_FILENO) == -1) throw SysError("dupping stdout"); Strings args_(args); args_.push_front(program); if (searchPath) execvp(program.c_str(), stringsToCharPtrs(args_).data()); else execv(program.c_str(), stringsToCharPtrs(args_).data()); throw SysError(format("executing `%1%'") % program); }); pipe.writeSide.close(); string result = drainFD(pipe.readSide); /* Wait for the child to finish. */ int status = pid.wait(true); if (!statusOk(status)) throw ExecError(format("program `%1%' %2%") % program % statusToString(status)); return result; } void closeMostFDs(const set<int> & exceptions) { int maxFD = 0; maxFD = sysconf(_SC_OPEN_MAX); for (int fd = 0; fd < maxFD; ++fd) if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO && exceptions.find(fd) == exceptions.end()) close(fd); /* ignore result */ } void closeOnExec(int fd) { int prev; if ((prev = fcntl(fd, F_GETFD, 0)) == -1 || fcntl(fd, F_SETFD, prev | FD_CLOEXEC) == -1) throw SysError("setting close-on-exec flag"); } ////////////////////////////////////////////////////////////////////// volatile sig_atomic_t _isInterrupted = 0; void _interrupted() { /* Block user interrupts while an exception is being handled. Throwing an exception while another exception is being handled kills the program! */ if (!std::uncaught_exception()) { _isInterrupted = 0; throw Interrupted("interrupted by the user"); } } ////////////////////////////////////////////////////////////////////// template<class C> C tokenizeString(const string & s, const string & separators) { C result; string::size_type pos = s.find_first_not_of(separators, 0); while (pos != string::npos) { string::size_type end = s.find_first_of(separators, pos + 1); if (end == string::npos) end = s.size(); string token(s, pos, end - pos); result.insert(result.end(), token); pos = s.find_first_not_of(separators, end); } return result; } template Strings tokenizeString(const string & s, const string & separators); template StringSet tokenizeString(const string & s, const string & separators); template vector<string> tokenizeString(const string & s, const string & separators); string concatStringsSep(const string & sep, const Strings & ss) { string s; foreach (Strings::const_iterator, i, ss) { if (s.size() != 0) s += sep; s += *i; } return s; } string concatStringsSep(const string & sep, const StringSet & ss) { string s; foreach (StringSet::const_iterator, i, ss) { if (s.size() != 0) s += sep; s += *i; } return s; } string chomp(const string & s) { size_t i = s.find_last_not_of(" \n\r\t"); return i == string::npos ? "" : string(s, 0, i + 1); } string statusToString(int status) { if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { if (WIFEXITED(status)) return (format("failed with exit code %1%") % WEXITSTATUS(status)).str(); else if (WIFSIGNALED(status)) { int sig = WTERMSIG(status); #if HAVE_STRSIGNAL const char * description = strsignal(sig); return (format("failed due to signal %1% (%2%)") % sig % description).str(); #else return (format("failed due to signal %1%") % sig).str(); #endif } else return "died abnormally"; } else return "succeeded"; } bool statusOk(int status) { return WIFEXITED(status) && WEXITSTATUS(status) == 0; } bool hasSuffix(const string & s, const string & suffix) { return s.size() >= suffix.size() && string(s, s.size() - suffix.size()) == suffix; } void expect(std::istream & str, const string & s) { char s2[s.size()]; str.read(s2, s.size()); if (string(s2, s.size()) != s) throw FormatError(format("expected string `%1%'") % s); } string parseString(std::istream & str) { string res; expect(str, "\""); int c; while ((c = str.get()) != '"') if (c == '\\') { c = str.get(); if (c == 'n') res += '\n'; else if (c == 'r') res += '\r'; else if (c == 't') res += '\t'; else res += c; } else res += c; return res; } bool endOfList(std::istream & str) { if (str.peek() == ',') { str.get(); return false; } if (str.peek() == ']') { str.get(); return true; } return false; } void ignoreException() { try { throw; } catch (std::exception & e) { printMsg(lvlError, format("error (ignored): %1%") % e.what()); } } static const string pathNullDevice = "/dev/null"; /* Common initialisation performed in child processes. */ void commonChildInit(Pipe & logPipe) { /* Put the child in a separate session (and thus a separate process group) so that it has no controlling terminal (meaning that e.g. ssh cannot open /dev/tty) and it doesn't receive terminal signals. */ if (setsid() == -1) throw SysError(format("creating a new session")); /* Dup the write side of the logger pipe into stderr. */ if (dup2(logPipe.writeSide, STDERR_FILENO) == -1) throw SysError("cannot pipe standard error into log file"); /* Dup stderr to stdout. */ if (dup2(STDERR_FILENO, STDOUT_FILENO) == -1) throw SysError("cannot dup stderr into stdout"); /* Reroute stdin to /dev/null. */ int fdDevNull = open(pathNullDevice.c_str(), O_RDWR); if (fdDevNull == -1) throw SysError(format("cannot open `%1%'") % pathNullDevice); if (dup2(fdDevNull, STDIN_FILENO) == -1) throw SysError("cannot dup null device into stdin"); close(fdDevNull); } ////////////////////////////////////////////////////////////////////// Agent::Agent(const string &command, const Strings &args, const std::map<string, string> &env) { debug(format("starting agent '%1%'") % command); /* Create a pipe to get the output of the child. */ fromAgent.create(); /* Create the communication pipes. */ toAgent.create(); /* Create a pipe to get the output of the builder. */ builderOut.create(); /* Fork the hook. */ pid = startProcess([&]() { commonChildInit(fromAgent); for (auto pair: env) { setenv(pair.first.c_str(), pair.second.c_str(), 1); } if (chdir("/") == -1) throw SysError("changing into `/"); /* Dup the communication pipes. */ if (dup2(toAgent.readSide, STDIN_FILENO) == -1) throw SysError("dupping to-hook read side"); /* Use fd 4 for the builder's stdout/stderr. */ if (dup2(builderOut.writeSide, 4) == -1) throw SysError("dupping builder's stdout/stderr"); Strings allArgs; allArgs.push_back(command); allArgs.insert(allArgs.end(), args.begin(), args.end()); // append execv(command.c_str(), stringsToCharPtrs(allArgs).data()); throw SysError(format("executing `%1%'") % command); }); pid.setSeparatePG(true); fromAgent.writeSide.close(); toAgent.readSide.close(); } Agent::~Agent() { try { toAgent.writeSide.close(); pid.kill(true); } catch (...) { ignoreException(); } } }