mmdebstrap/tests/dev-ptmx

#!/bin/sh
set -eu
export LC_ALL=C.UTF-8

if [ {{ MODE }} != unshare ] && [ {{ MODE }} != root ]; then
  echo "test requires root or unshare mode" >&2
  exit 1
fi

prefix=
if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
  if ! id "${SUDO_USER:-user}" >/dev/null 2>&1; then
    if [ ! -e /mmdebstrap-testenv ]; then
      echo "this test modifies the system and should only be run inside a container" >&2
      exit 1
    fi
    useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
  fi
  prefix="runuser -u ${SUDO_USER:-user} --"
fi

# this mimics what apt does in apt-pkg/deb/dpkgpm.cc/pkgDPkgPM::StartPtyMagic()
cat >/tmp/test.c <<'END'
#define _GNU_SOURCE

#include <stdlib.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <signal.h>

int main() {
	int ret;
	int fd = posix_openpt(O_RDWR | O_NOCTTY);
	if (fd < 0) {
		perror("posix_openpt");
		return 1;
	}
	char buf[64]; // 64 is used by apt
	ret = ptsname_r(fd, buf, sizeof(buf));
	if (ret != 0) {
		perror("ptsname_r");
		return 1;
	}
	ret = grantpt(fd);
	if (ret == -1) {
		perror("grantpt");
		return 1;
	}
	struct termios origtt;
	ret = tcgetattr(STDIN_FILENO, &origtt);
	if (ret != 0) {
		perror("tcgetattr1");
		return 1;
	}
	struct termios tt;
	ret = tcgetattr(STDOUT_FILENO, &tt);
	if (ret != 0) {
		perror("tcgetattr2");
		return 1;
	}
	struct winsize win;
	ret = ioctl(STDOUT_FILENO, TIOCGWINSZ, &win);
	if (ret < 0) {
		perror("ioctl stdout TIOCGWINSZ");
		return 1;
	}
	ret = ioctl(fd, TIOCSWINSZ, &win);
	if (ret < 0) {
		perror("ioctl fd TIOCGWINSZ");
		return 1;
	}
	ret = tcsetattr(fd, TCSANOW, &tt);
	if (ret != 0) {
		perror("tcsetattr1");
		return 1;
	}
	cfmakeraw(&tt);
	tt.c_lflag &= ~ECHO;
	tt.c_lflag |= ISIG;
	sigset_t sigmask;
	sigset_t sigmask_old;
	ret = sigemptyset(&sigmask);
	if (ret != 0) {
		perror("sigemptyset");
		return 1;
	}
	ret = sigaddset(&sigmask, SIGTTOU);
	if (ret != 0) {
		perror("sigaddset");
		return 1;
	}
	ret = sigprocmask(SIG_BLOCK,&sigmask, &sigmask_old);
	if (ret != 0) {
		perror("sigprocmask1");
		return 1;
	}
	ret = tcsetattr(STDIN_FILENO, TCSAFLUSH, &tt);
	if (ret != 0) {
		perror("tcsetattr2");
		return 1;
	}
	ret = sigprocmask(SIG_BLOCK,&sigmask_old, NULL);
	if (ret != 0) {
		perror("sigprocmask2");
		return 1;
	}
	ret = tcsetattr(STDIN_FILENO, TCSAFLUSH, &origtt);
	if (ret != 0) {
		perror("tcsetattr3");
		return 1;
	}
	return 0;
}
END

# use script to create a fake tty
# run all tests as root and as a normal user (the latter requires ptmxmode=666)
script -qfec "$prefix {{ CMD }} --mode={{ MODE }} --variant=apt \
	--include=gcc,libc6-dev,python3,passwd \
	--customize-hook='chroot \"\$1\" useradd --home-dir /home/user --create-home user' \
	--customize-hook='chroot \"\$1\" python3 -c \"import pty; print(pty.openpty())\"' \
	--customize-hook='chroot \"\$1\" runuser -u user -- python3 -c \"import pty; print(pty.openpty())\"' \
	--customize-hook='chroot \"\$1\" script -c \"echo foobar\"' \
	--customize-hook='chroot \"\$1\" runuser -u user -- env --chdir=/home/user script -c \"echo foobar\"' \
	--customize-hook='chroot \"\$1\" apt-get install --yes doc-debian 2>&1 | tee \"\$1\"/tmp/log' \
	--customize-hook=\"copy-in /tmp/test.c /tmp\" \
	--customize-hook='chroot \"\$1\" gcc /tmp/test.c -o /tmp/test' \
	--customize-hook='chroot \"\$1\" /tmp/test' \
	--customize-hook='chroot \"\$1\" runuser -u user -- /tmp/test' \
	--customize-hook='rm \"\$1\"/tmp/test \"\$1\"/tmp/test.c' \
	--customize-hook=\"copy-out /tmp/log /tmp\" \
	{{ DIST }} /dev/null {{ MIRROR }}" /dev/null

fail=0
[ -r /tmp/log ] || fail=1
grep '^E:' /tmp/log && fail=1
grep 'Can not write log' /tmp/log && fail=1
grep 'posix_openpt' /tmp/log && fail=1
grep 'No such file or directory' /tmp/log && fail=1
if [ $fail -eq 1 ]; then
  echo "apt failed to write log:" >&2
  cat /tmp/log >&2
  exit 1
fi

rm /tmp/test.c /tmp/log