spawn: support absolute paths

[public-inbox.git] / lib / PublicInbox / Spawn.pm

diff --git a/lib/PublicInbox/Spawn.pm b/lib/PublicInbox/Spawn.pm
index 83730302a00ba126d435f63f359511a08e89b89a..202cfcaebee7cba63ccabc68378dd3464754220e 100644 (file)
--- a/lib/PublicInbox/Spawn.pm
+++ b/lib/PublicInbox/Spawn.pm
@@ -1,4 +1,4 @@
-# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# Copyright (C) 2016-2018 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 #
 # This allows vfork to be used for spawning subprocesses if
@@ -22,6 +22,8 @@ our @EXPORT_OK = qw/which spawn popen_rd/;
 my $vfork_spawn = <<'VFORK_SPAWN';
 #include <sys/types.h>
 #include <sys/uio.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 #include <unistd.h>
 #include <alloca.h>
 #include <signal.h>
@@ -74,17 +76,18 @@ static void xerr(const char *msg)
  * whatever we'll need in the future.
  * Be sure to update PublicInbox::SpawnPP if this changes
  */
-int public_inbox_fork_exec(int in, int out, int err,
-                       SV *file, SV *cmdref, SV *envref)
+int pi_fork_exec(int in, int out, int err,
+                       SV *file, SV *cmdref, SV *envref, SV *rlimref)
 {
        AV *cmd = (AV *)SvRV(cmdref);
        AV *env = (AV *)SvRV(envref);
+       AV *rlim = (AV *)SvRV(rlimref);
        const char *filename = SvPV_nolen(file);
        pid_t pid;
        char **argv, **envp;
        I32 max;
        sigset_t set, old;
-       int ret;
+       int ret, errnum;
 
        argv = AV_ALLOCA(cmd, max);
        av2c_copy(argv, cmd, max);
@@ -99,12 +102,27 @@ int public_inbox_fork_exec(int in, int out, int err,
        pid = vfork();
        if (pid == 0) {
                int sig;
+               I32 i, max;
 
                REDIR(in, 0);
                REDIR(out, 1);
                REDIR(err, 2);
                for (sig = 1; sig < NSIG; sig++)
                        signal(sig, SIG_DFL); /* ignore errors on signals */
+
+               max = av_len(rlim);
+               for (i = 0; i < max; i += 3) {
+                       struct rlimit rl;
+                       SV **res = av_fetch(rlim, i, 0);
+                       SV **soft = av_fetch(rlim, i + 1, 0);
+                       SV **hard = av_fetch(rlim, i + 2, 0);
+
+                       rl.rlim_cur = SvIV(*soft);
+                       rl.rlim_max = SvIV(*hard);
+                       if (setrlimit(SvIV(*res), &rl) < 0)
+                               xerr("sertlimit");
+               }
+
                /*
                 * don't bother unblocking, we don't want signals
                 * to the group taking out a subprocess
@@ -112,8 +130,10 @@ int public_inbox_fork_exec(int in, int out, int err,
                execve(filename, argv, envp);
                xerr("execve failed");
        }
+       errnum = errno;
        ret = sigprocmask(SIG_SETMASK, &old, NULL);
        assert(ret == 0 && "BUG calling sigprocmask to restore");
+       errno = errnum;
 
        return (int)pid;
 }
@@ -143,12 +163,12 @@ if (defined $vfork_spawn) {
 unless (defined $vfork_spawn) {
        require PublicInbox::SpawnPP;
        no warnings 'once';
-       *public_inbox_fork_exec = *PublicInbox::SpawnPP::public_inbox_fork_exec
+       *pi_fork_exec = *PublicInbox::SpawnPP::pi_fork_exec
 }
 
-# n.b. we never use absolute paths with this
 sub which ($) {
        my ($file) = @_;
+       return $file if index($file, '/') == 0;
        foreach my $p (split(':', $ENV{PATH})) {
                $p .= "/$file";
                return $p if -x $p;
@@ -180,7 +200,25 @@ sub spawn ($;$$) {
        my $in = $opts->{0} || 0;
        my $out = $opts->{1} || 1;
        my $err = $opts->{2} || 2;
-       public_inbox_fork_exec($in, $out, $err, $f, $cmd, \@env);
+       my $rlim = [];
+
+       foreach my $l (qw(RLIMIT_CPU RLIMIT_CORE RLIMIT_DATA)) {
+               defined(my $v = $opts->{$l}) or next;
+               my ($soft, $hard);
+               if (ref($v)) {
+                       ($soft, $hard) = @$v;
+               } else {
+                       $soft = $hard = $v;
+               }
+               my $r = eval "require BSD::Resource; BSD::Resource::$l();";
+               unless (defined $r) {
+                       warn "$l undefined by BSD::Resource: $@\n";
+                       next;
+               }
+               push @$rlim, $r, $soft, $hard;
+       }
+       my $pid = pi_fork_exec($in, $out, $err, $f, $cmd, \@env, $rlim);
+       $pid < 0 ? undef : $pid;
 }
 
 sub popen_rd {
@@ -191,6 +229,7 @@ sub popen_rd {
        IO::Handle::blocking($r, $blocking) if defined $blocking;
        $opts->{1} = fileno($w);
        my $pid = spawn($cmd, $env, $opts);
+       return unless defined $pid;
        return ($r, $pid) if wantarray;
        my $ret = gensym;
        tie *$ret, 'PublicInbox::ProcessPipe', $pid, $r;