&CORE::setpgrp()

This commit allows &CORE::setpgrp to be called through references and
via ampersand syntax.  pp_setpgrp is modified to take into account the
nulls pushed on to the stack in pp_coreargs, which happens because
pp_coreargs has no other way to tell setpgrp how many arguments it’s
actually getting.  See commit 0163043a for details.

3 files changed, 16 insertions, 9 deletions

diff --git a/gv.c b/gv.c
index 1c337ef1f6..086e398a3f 100644
--- a/gv.c
+++ b/gv.c
@@ -1358,7 +1358,7 @@ Perl_gv_fetchpvn_flags(pTHX_ const char *nambeg, STRLEN full_len, I32 flags,
 	    case KEY_lstat:
 	    case KEY_pop:
 	    case KEY_push:
-	    case KEY_setpgrp: case KEY_shift:
+	    case KEY_shift:
 	    case KEY_splice:
 	    case KEY_stat:
 	    case KEY_system:
diff --git a/pp_sys.c b/pp_sys.c
index 7ae1644728..5cd9ef6613 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -4342,16 +4342,12 @@ PP(pp_setpgrp)
     dVAR; dSP; dTARGET;
     Pid_t pgrp;
     Pid_t pid;
-    if (MAXARG == 1) pgrp = 0, pid = TOPi;
-    else if (MAXARG < 2) {
-	pgrp = 0;
+    pgrp = MAXARG == 2 && (TOPs||POPs) ? POPi : 0;
+    if (MAXARG > 0) pid = TOPs && TOPi;
+    else {
 	pid = 0;
 	XPUSHi(-1);
     }
-    else {
-	pgrp = POPi;
-	pid = TOPi;
-    }
 
     TAINT_PROPER("setpgrp");
 #ifdef BSD_SETPGRP
diff --git a/t/op/coreamp.t b/t/op/coreamp.t
index 50897a0109..5ef3a2bd39 100644
--- a/t/op/coreamp.t
+++ b/t/op/coreamp.t
@@ -657,7 +657,18 @@ test_proto "sem$_" for qw "ctl get op";
 test_proto 'send';
 
 test_proto "set$_" for qw '
-  grent hostent netent priority protoent pwent servent sockopt
+  grent hostent netent
+';
+
+test_proto 'setpgrp';
+$tests +=2;
+eval { &mysetpgrp( 0) };
+pass "&setpgrp with one argument";
+eval { &mysetpgrp };
+pass "&setpgrp with no arguments";
+
+test_proto "set$_" for qw '
+  priority protoent pwent servent sockopt
 ';
 
 test_proto "shm$_" for qw "ctl get read write";