our @EXPORT_OK = qw(which spawn popen_rd run_die nodatacow_dir);
our @RLIMITS = qw(RLIMIT_CPU RLIMIT_CORE RLIMIT_DATA);
-my $vfork_spawn = <<'VFORK_SPAWN';
+my $all_libc = <<'ALL_LIBC'; # all *nix systems we support
+#include <sys/resource.h>
+#include <sys/socket.h>
#include <sys/types.h>
#include <sys/time.h>
-#include <sys/resource.h>
+#include <sys/uio.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
} while (0)
/* needs to be safe inside a vfork'ed process */
-static void exit_err(int *cerrnum)
+static void exit_err(const char *fn, volatile int *cerrnum)
{
*cerrnum = errno;
+ write(2, fn, strlen(fn));
_exit(1);
}
* Be sure to update PublicInbox::SpawnPP if this changes
*/
int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
- const char *cd)
+ const char *cd, int pgid)
{
AV *redir = (AV *)SvRV(redirref);
AV *cmd = (AV *)SvRV(cmdref);
const char *filename = SvPV_nolen(file);
pid_t pid;
char **argv, **envp;
- sigset_t set, old, cset;
- int ret, perrnum, cerrnum = 0;
+ sigset_t set, old;
+ int ret, perrnum;
+ volatile int cerrnum = 0; /* shared due to vfork */
+ int chld_is_member;
+ I32 max_fd = av_len(redir);
AV2C_COPY(argv, cmd);
AV2C_COPY(envp, env);
- ret = sigfillset(&set);
- assert(ret == 0 && "BUG calling sigfillset");
- ret = sigprocmask(SIG_SETMASK, &set, &old);
- assert(ret == 0 && "BUG calling sigprocmask to block");
- ret = sigemptyset(&cset);
- assert(ret == 0 && "BUG calling sigemptyset");
- ret = sigaddset(&cset, SIGCHLD);
- assert(ret == 0 && "BUG calling sigaddset for SIGCHLD");
+ if (sigfillset(&set)) return -1;
+ if (sigprocmask(SIG_SETMASK, &set, &old)) return -1;
+ chld_is_member = sigismember(&old, SIGCHLD);
+ if (chld_is_member < 0) return -1;
+ if (chld_is_member > 0)
+ sigdelset(&old, SIGCHLD);
+
pid = vfork();
if (pid == 0) {
int sig;
- I32 i, child_fd, max = av_len(redir);
+ I32 i, child_fd, max_rlim;
- for (child_fd = 0; child_fd <= max; child_fd++) {
+ for (child_fd = 0; child_fd <= max_fd; child_fd++) {
SV **parent = av_fetch(redir, child_fd, 0);
int parent_fd = SvIV(*parent);
if (parent_fd == child_fd)
continue;
if (dup2(parent_fd, child_fd) < 0)
- exit_err(&cerrnum);
+ exit_err("dup2", &cerrnum);
}
+ if (pgid >= 0 && setpgid(0, pgid) < 0)
+ exit_err("setpgid", &cerrnum);
for (sig = 1; sig < NSIG; sig++)
signal(sig, SIG_DFL); /* ignore errors on signals */
if (*cd && chdir(cd) < 0)
- exit_err(&cerrnum);
+ exit_err("chdir", &cerrnum);
- max = av_len(rlim);
- for (i = 0; i < max; i += 3) {
+ max_rlim = av_len(rlim);
+ for (i = 0; i < max_rlim; i += 3) {
struct rlimit rl;
SV **res = av_fetch(rlim, i, 0);
SV **soft = av_fetch(rlim, i + 1, 0);
rl.rlim_cur = SvIV(*soft);
rl.rlim_max = SvIV(*hard);
if (setrlimit(SvIV(*res), &rl) < 0)
- exit_err(&cerrnum);
+ exit_err("setrlimit", &cerrnum);
}
- /*
- * don't bother unblocking other signals for now, just SIGCHLD.
- * we don't want signals to the group taking out a subprocess
- */
- (void)sigprocmask(SIG_UNBLOCK, &cset, NULL);
+ (void)sigprocmask(SIG_SETMASK, &old, NULL);
execve(filename, argv, envp);
- exit_err(&cerrnum);
+ exit_err("execve", &cerrnum);
}
perrnum = errno;
+ if (chld_is_member > 0)
+ sigaddset(&old, SIGCHLD);
ret = sigprocmask(SIG_SETMASK, &old, NULL);
assert(ret == 0 && "BUG calling sigprocmask to restore");
if (cerrnum) {
+ int err_fd = STDERR_FILENO;
+ if (err_fd <= max_fd) {
+ SV **parent = av_fetch(redir, err_fd, 0);
+ err_fd = SvIV(*parent);
+ }
if (pid > 0)
waitpid(pid, NULL, 0);
pid = -1;
+ /* continue message started by exit_err in child */
+ dprintf(err_fd, ": %s\n", strerror(cerrnum));
errno = cerrnum;
} else if (perrnum) {
errno = perrnum;
}
return (int)pid;
}
-VFORK_SPAWN
-
-# btrfs on Linux is copy-on-write (COW) by default. As of Linux 5.7,
-# this still leads to fragmentation for SQLite and Xapian files where
-# random I/O happens, so we disable COW just for SQLite files and Xapian
-# directories. Disabling COW disables checksumming, so we only do this
-# for regeneratable files, and not canonical git storage (git doesn't
-# checksum refs, only data under $GIT_DIR/objects).
-my $set_nodatacow = $^O eq 'linux' ? <<'SET_NODATACOW' : '';
-#include <sys/ioctl.h>
-#include <sys/vfs.h>
-#include <linux/magic.h>
-#include <linux/fs.h>
-#include <dirent.h>
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-
-void nodatacow_fd(int fd)
-{
- struct statfs buf;
- int val = 0;
-
- if (fstatfs(fd, &buf) < 0) {
- fprintf(stderr, "fstatfs: %s\\n", strerror(errno));
- return;
- }
-
- /* only btrfs is known to have this problem, so skip for non-btrfs */
- if (buf.f_type != BTRFS_SUPER_MAGIC)
- return;
-
- if (ioctl(fd, FS_IOC_GETFLAGS, &val) < 0) {
- fprintf(stderr, "FS_IOC_GET_FLAGS: %s\\n", strerror(errno));
- return;
- }
- val |= FS_NOCOW_FL;
- if (ioctl(fd, FS_IOC_SETFLAGS, &val) < 0)
- fprintf(stderr, "FS_IOC_SET_FLAGS: %s\\n", strerror(errno));
-}
-
-void nodatacow_dir(const char *dir)
-{
- DIR *dh = opendir(dir);
- int fd;
-
- if (!dh) croak("opendir(%s): %s", dir, strerror(errno));
- fd = dirfd(dh);
- if (fd >= 0)
- nodatacow_fd(fd);
- /* ENOTSUP probably won't happen under Linux... */
- closedir(dh);
-}
-SET_NODATACOW
-
-# last choice for script/lei, 1st choice for lei internals
-# compatible with PublicInbox::CmdIPC4
-my $fdpass = <<'FDPASS';
-#include <sys/types.h>
-#include <sys/uio.h>
-#include <sys/socket.h>
#if defined(CMSG_SPACE) && defined(CMSG_LEN)
-#define SEND_FD_CAPA 5
+#define SEND_FD_CAPA 10
#define SEND_FD_SPACE (SEND_FD_CAPA * sizeof(int))
union my_cmsg {
struct cmsghdr hdr;
Inline_Stack_Done;
}
#endif /* defined(CMSG_SPACE) && defined(CMSG_LEN) */
-FDPASS
+ALL_LIBC
+
+# btrfs on Linux is copy-on-write (COW) by default. As of Linux 5.7,
+# this still leads to fragmentation for SQLite and Xapian files where
+# random I/O happens, so we disable COW just for SQLite files and Xapian
+# directories. Disabling COW disables checksumming, so we only do this
+# for regeneratable files, and not canonical git storage (git doesn't
+# checksum refs, only data under $GIT_DIR/objects).
+my $set_nodatacow = $^O eq 'linux' ? <<'SET_NODATACOW' : '';
+#include <sys/ioctl.h>
+#include <sys/vfs.h>
+#include <linux/magic.h>
+#include <linux/fs.h>
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+void nodatacow_fd(int fd)
+{
+ struct statfs buf;
+ int val = 0;
+
+ if (fstatfs(fd, &buf) < 0) {
+ fprintf(stderr, "fstatfs: %s\\n", strerror(errno));
+ return;
+ }
+
+ /* only btrfs is known to have this problem, so skip for non-btrfs */
+ if (buf.f_type != BTRFS_SUPER_MAGIC)
+ return;
+
+ if (ioctl(fd, FS_IOC_GETFLAGS, &val) < 0) {
+ fprintf(stderr, "FS_IOC_GET_FLAGS: %s\\n", strerror(errno));
+ return;
+ }
+ val |= FS_NOCOW_FL;
+ if (ioctl(fd, FS_IOC_SETFLAGS, &val) < 0)
+ fprintf(stderr, "FS_IOC_SET_FLAGS: %s\\n", strerror(errno));
+}
+
+void nodatacow_dir(const char *dir)
+{
+ DIR *dh = opendir(dir);
+ int fd;
+
+ if (!dh) croak("opendir(%s): %s", dir, strerror(errno));
+ fd = dirfd(dh);
+ if (fd >= 0)
+ nodatacow_fd(fd);
+ /* ENOTSUP probably won't happen under Linux... */
+ closedir(dh);
+}
+SET_NODATACOW
my $inline_dir = $ENV{PERL_INLINE_DIRECTORY} //= (
$ENV{XDG_CACHE_HOME} //
( ($ENV{HOME} // '/nonexistent').'/.cache' )
).'/public-inbox/inline-c';
-$set_nodatacow = $vfork_spawn = $fdpass = undef unless -d $inline_dir && -w _;
-if (defined $vfork_spawn) {
+$set_nodatacow = $all_libc = undef unless -d $inline_dir && -w _;
+if (defined $all_libc) {
# Inline 0.64 or later has locking in multi-process env,
# but we support 0.5 on Debian wheezy
use Fcntl qw(:flock);
my $f = "$inline_dir/.public-inbox.lock";
open my $fh, '>', $f or die "failed to open $f: $!\n";
flock($fh, LOCK_EX) or die "LOCK_EX failed on $f: $!\n";
- eval 'use Inline C => $vfork_spawn.$fdpass.$set_nodatacow';
+ eval 'use Inline C => $all_libc.$set_nodatacow';
# . ', BUILD_NOISY => 1';
my $err = $@;
my $ndc_err;
if ($err && $set_nodatacow) { # missing Linux kernel headers
$ndc_err = $err;
undef $set_nodatacow;
- eval 'use Inline C => $vfork_spawn . $fdpass';
+ eval 'use Inline C => $all_libc';
}
flock($fh, LOCK_UN) or die "LOCK_UN failed on $f: $!\n";
die $err if $err;
};
if ($@) {
warn "Inline::C failed for vfork: $@\n";
- $set_nodatacow = $vfork_spawn = $fdpass = undef;
+ $set_nodatacow = $all_libc = undef;
}
}
-unless (defined $vfork_spawn) {
+unless ($all_libc) {
require PublicInbox::SpawnPP;
*pi_fork_exec = \&PublicInbox::SpawnPP::pi_fork_exec
}
}
undef $set_nodatacow;
-undef $vfork_spawn;
-undef $fdpass;
+undef $all_libc;
sub which ($) {
my ($file) = @_;
return $file if index($file, '/') >= 0;
- foreach my $p (split(':', $ENV{PATH})) {
+ for my $p (split(/:/, $ENV{PATH})) {
$p .= "/$file";
return $p if -x $p;
}
sub spawn ($;$$) {
my ($cmd, $env, $opts) = @_;
- my $f = which($cmd->[0]);
- defined $f or die "$cmd->[0]: command not found\n";
+ my $f = which($cmd->[0]) // die "$cmd->[0]: command not found\n";
my @env;
$opts ||= {};
-
- my %env = $env ? (%ENV, %$env) : %ENV;
+ my %env = (%ENV, $env ? %$env : ());
while (my ($k, $v) = each %env) {
- push @env, "$k=$v";
+ push @env, "$k=$v" if defined($v);
}
my $redir = [];
for my $child_fd (0..2) {
my $parent_fd = $opts->{$child_fd};
if (defined($parent_fd) && $parent_fd !~ /\A[0-9]+\z/) {
- defined(my $fd = fileno($parent_fd)) or
+ my $fd = fileno($parent_fd) //
die "$parent_fd not an IO GLOB? $!";
$parent_fd = $fd;
}
my $rlim = [];
foreach my $l (@RLIMITS) {
- defined(my $v = $opts->{$l}) or next;
+ my $v = $opts->{$l} // next;
my $r = eval "require BSD::Resource; BSD::Resource::$l();";
unless (defined $r) {
warn "$l undefined by BSD::Resource: $@\n";
push @$rlim, $r, @$v;
}
my $cd = $opts->{'-C'} // ''; # undef => NULL mapping doesn't work?
- my $pid = pi_fork_exec($redir, $f, $cmd, \@env, $rlim, $cd);
+ my $pgid = $opts->{pgid} // -1;
+ my $pid = pi_fork_exec($redir, $f, $cmd, \@env, $rlim, $cd, $pgid);
die "fork_exec @$cmd failed: $!\n" unless $pid > 0;
$pid;
}