X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSpawn.pm;h=1c74a5964aa59235d51eaa6af7bbb9b37fecb4eb;hb=55b707d788ce13696e4411389583e720ea6dab01;hp=b946a66373b84faedaef1a71d02329a2cf8587fe;hpb=2df8cfd320dc9efdf3c2764b2c60ec457c1b024f;p=public-inbox.git

diff --git a/lib/PublicInbox/Spawn.pm b/lib/PublicInbox/Spawn.pm
index b946a663..1c74a596 100644
--- a/lib/PublicInbox/Spawn.pm
+++ b/lib/PublicInbox/Spawn.pm
@@ -15,7 +15,6 @@ use strict;
 use warnings;
 use base qw(Exporter);
 use Symbol qw(gensym);
-use IO::Handle;
 use PublicInbox::ProcessPipe;
 our @EXPORT_OK = qw/which spawn popen_rd/;
 sub RLIMITS () { qw(RLIMIT_CPU RLIMIT_CORE RLIMIT_DATA) }
@@ -56,43 +55,22 @@ my $vfork_spawn = <<'VFORK_SPAWN';
 	dst[real_len] = 0; \
 } while (0)
 
-static void *deconst(const char *s)
-{
-	union { const char *in; void *out; } u;
-	u.in = s;
-	return u.out;
-}
-
 /* needs to be safe inside a vfork'ed process */
-static void xerr(const char *msg)
+static void exit_err(int *cerrnum)
 {
-	struct iovec iov[3];
-	const char *err = strerror(errno); /* should be safe in practice */
-
-	iov[0].iov_base = deconst(msg);
-	iov[0].iov_len = strlen(msg);
-	iov[1].iov_base = deconst(err);
-	iov[1].iov_len = strlen(err);
-	iov[2].iov_base = deconst("\n");
-	iov[2].iov_len = 1;
-	writev(2, iov, 3);
+	*cerrnum = errno;
 	_exit(1);
 }
 
-#define REDIR(var,fd) do { \
-	if (var != fd && dup2(var, fd) < 0) \
-		xerr("error redirecting std"#var ": "); \
-} while (0)
-
 /*
- * unstable internal API.  This was easy to implement but does not
- * support arbitrary redirects.  It'll be updated depending on
+ * unstable internal API.  It'll be updated depending on
  * whatever we'll need in the future.
  * Be sure to update PublicInbox::SpawnPP if this changes
  */
-int pi_fork_exec(int in, int out, int err,
-			SV *file, SV *cmdref, SV *envref, SV *rlimref)
+int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
+		 const char *cd)
 {
+	AV *redir = (AV *)SvRV(redirref);
 	AV *cmd = (AV *)SvRV(cmdref);
 	AV *env = (AV *)SvRV(envref);
 	AV *rlim = (AV *)SvRV(rlimref);
@@ -100,7 +78,7 @@ int pi_fork_exec(int in, int out, int err,
 	pid_t pid;
 	char **argv, **envp;
 	sigset_t set, old;
-	int ret, errnum;
+	int ret, perrnum, cerrnum = 0;
 
 	AV2C_COPY(argv, cmd);
 	AV2C_COPY(envp, env);
@@ -112,13 +90,20 @@ int pi_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);
+		I32 i, child_fd, max = av_len(redir);
+
+		for (child_fd = 0; child_fd <= max; 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);
+		}
 		for (sig = 1; sig < NSIG; sig++)
 			signal(sig, SIG_DFL); /* ignore errors on signals */
+		if (*cd && chdir(cd) < 0)
+			exit_err(&cerrnum);
 
 		max = av_len(rlim);
 		for (i = 0; i < max; i += 3) {
@@ -130,7 +115,7 @@ int pi_fork_exec(int in, int out, int err,
 			rl.rlim_cur = SvIV(*soft);
 			rl.rlim_max = SvIV(*hard);
 			if (setrlimit(SvIV(*res), &rl) < 0)
-				xerr("sertlimit");
+				exit_err(&cerrnum);
 		}
 
 		/*
@@ -138,13 +123,19 @@ int pi_fork_exec(int in, int out, int err,
 		 * to the group taking out a subprocess
 		 */
 		execve(filename, argv, envp);
-		xerr("execve failed");
+		exit_err(&cerrnum);
 	}
-	errnum = errno;
+	perrnum = errno;
 	ret = sigprocmask(SIG_SETMASK, &old, NULL);
 	assert(ret == 0 && "BUG calling sigprocmask to restore");
-	errno = errnum;
-
+	if (cerrnum) {
+		if (pid > 0)
+			waitpid(pid, NULL, 0);
+		pid = -1;
+		errno = cerrnum;
+	} else if (perrnum) {
+		errno = perrnum;
+	}
 	return (int)pid;
 }
 VFORK_SPAWN
@@ -172,8 +163,7 @@ if (defined $vfork_spawn) {
 
 unless (defined $vfork_spawn) {
 	require PublicInbox::SpawnPP;
-	no warnings 'once';
-	*pi_fork_exec = *PublicInbox::SpawnPP::pi_fork_exec
+	*pi_fork_exec = \&PublicInbox::SpawnPP::pi_fork_exec
 }
 
 sub which ($) {
@@ -193,23 +183,20 @@ sub spawn ($;$$) {
 	my @env;
 	$opts ||= {};
 
-	my %env = $opts->{-env} ? () : %ENV;
-	if ($env) {
-		foreach my $k (keys %$env) {
-			my $v = $env->{$k};
-			if (defined $v) {
-				$env{$k} = $v;
-			} else {
-				delete $env{$k};
-			}
-		}
-	}
+	my %env = $env ? (%ENV, %$env) : %ENV;
 	while (my ($k, $v) = each %env) {
 		push @env, "$k=$v";
 	}
-	my $in = $opts->{0} || 0;
-	my $out = $opts->{1} || 1;
-	my $err = $opts->{2} || 2;
+	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
+					die "$parent_fd not an IO GLOB? $!";
+			$parent_fd = $fd;
+		}
+		$redir->[$child_fd] = $parent_fd // $child_fd;
+	}
 	my $rlim = [];
 
 	foreach my $l (RLIMITS()) {
@@ -221,7 +208,8 @@ sub spawn ($;$$) {
 		}
 		push @$rlim, $r, @$v;
 	}
-	my $pid = pi_fork_exec($in, $out, $err, $f, $cmd, \@env, $rlim);
+	my $cd = $opts->{'-C'} // ''; # undef => NULL mapping doesn't work?
+	my $pid = pi_fork_exec($redir, $f, $cmd, \@env, $rlim, $cd);
 	$pid < 0 ? undef : $pid;
 }