-# Copyright (C) 2016-2018 all contributors <meta@public-inbox.org>
+# Copyright (C) 2016-2019 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
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
-#include <alloca.h>
-#include <signal.h>
-#include <assert.h>
+#include <stdlib.h>
-#define AV_ALLOCA(av, max) alloca((max = (av_len((av)) + 1)) * sizeof(char *))
+/* some platforms need alloca.h, but some don't */
+#if defined(__GNUC__) && !defined(alloca)
+# define alloca(sz) __builtin_alloca(sz)
+#endif
-static void av2c_copy(char **dst, AV *src, I32 max)
-{
- I32 i;
+#include <signal.h>
+#include <assert.h>
- for (i = 0; i < max; i++) {
- SV **sv = av_fetch(src, i, 0);
- dst[i] = sv ? SvPV_nolen(*sv) : 0;
- }
- dst[max] = 0;
-}
+/*
+ * From the av_len apidoc:
+ * Note that, unlike what the name implies, it returns
+ * the highest index in the array, so to get the size of
+ * the array you need to use "av_len(av) + 1".
+ * This is unlike "sv_len", which returns what you would expect.
+ */
+#define AV2C_COPY(dst, src) do { \
+ I32 i; \
+ I32 top_index = av_len(src); \
+ I32 real_len = top_index + 1; \
+ I32 capa = real_len + 1; \
+ dst = alloca(capa * sizeof(char *)); \
+ for (i = 0; i < real_len; i++) { \
+ SV **sv = av_fetch(src, i, 0); \
+ dst[i] = SvPV_nolen(*sv); \
+ } \
+ dst[real_len] = 0; \
+} while (0)
static void *deconst(const char *s)
{
const char *filename = SvPV_nolen(file);
pid_t pid;
char **argv, **envp;
- I32 max;
sigset_t set, old;
int ret, errnum;
- argv = AV_ALLOCA(cmd, max);
- av2c_copy(argv, cmd, max);
-
- envp = AV_ALLOCA(env, max);
- av2c_copy(envp, env, max);
+ AV2C_COPY(argv, cmd);
+ AV2C_COPY(envp, env);
ret = sigfillset(&set);
assert(ret == 0 && "BUG calling sigfillset");
sub which ($) {
my ($file) = @_;
- return $file if index($file, '/') == 0;
+ return $file if index($file, '/') >= 0;
foreach my $p (split(':', $ENV{PATH})) {
$p .= "/$file";
return $p if -x $p;
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=$v";
}
my ($cmd, $env, $opts) = @_;
pipe(my ($r, $w)) or die "pipe: $!\n";
$opts ||= {};
- my $blocking = $opts->{Blocking};
- IO::Handle::blocking($r, $blocking) if defined $blocking;
$opts->{1} = fileno($w);
my $pid = spawn($cmd, $env, $opts);
return unless defined $pid;