* perthread.h (vfork_save): Add ctty, sid, pgid, exitval fields.

(vfork_save::restore_pid): New method.
(vfork_save::restore_exit): New method.
* fork.cc (vfork): Save ctty, sid, pgid and restore them when returning to
"parent".  Use exitval field if exiting but never created a new process.
* syscalls.cc (setsid): Detect when in "vfork" and force an actual fork so that
pid will be allocated (UGLY!).
(getsid): New function.
* dcrt0.cc (do_exit): Use vfork_save::restore_exit method for returning from a
vfork.
* spawn.cc (spawnve): Use vfork_save::{restore_pid,restore_exit} methods for
returning from vfork.
* cygwin.din: Export getsid.
* include/cygwin/version.h: Bump api minor number.
* malloc.cc: #ifdef sYSTRIm for when MORECORE_CANNOT_TRIM is true.

1 files changed, 41 insertions, 4 deletions

diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 31eed42b2..f047cbd1c 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -36,6 +36,9 @@ details. */
 #include <unistd.h>
 #include "shared_info.h"
 #include "cygheap.h"
+#define NEED_VFORK
+#include <setjmp.h>
+#include "perthread.h"
 
 SYSTEM_INFO system_info;
 
@@ -265,11 +268,24 @@ getppid ()
 extern "C" pid_t
 setsid (void)
 {
-  if (myself->pgid != _getpid ())
+  vfork_save *vf = vfork_storage.val ();
+  /* This is a horrible, horrible kludge */
+  if (vf && vf->pid < 0)
     {
-      if (myself->ctty == TTY_CONSOLE &&
-	  !cygheap->fdtab.has_console_fds () &&
-	  !check_pty_fds ())
+      pid_t pid = fork ();
+      if (pid > 0)
+	{
+	  syscall_printf ("longjmping due to vfork");
+	  vf->restore_pid (pid);
+	}
+      /* assuming that fork was successful */
+    }
+
+  if (myself->pgid != myself->pid)
+    {
+      if (myself->ctty == TTY_CONSOLE
+	  && !cygheap->fdtab.has_console_fds ()
+	  && !check_pty_fds ())
 	FreeConsole ();
       myself->ctty = -1;
       myself->sid = _getpid ();
@@ -277,10 +293,31 @@ setsid (void)
       syscall_printf ("sid %d, pgid %d, ctty %d", myself->sid, myself->pgid, myself->ctty);
       return myself->sid;
     }
+
   set_errno (EPERM);
   return -1;
 }
 
+extern "C" pid_t
+getsid (pid_t pid)
+{
+  pid_t res;
+  if (!pid)
+    res = myself->sid;
+  else
+    {
+      pinfo p (pid);
+      if (p)
+	res = p->sid;
+      else
+	{
+	  set_errno (ESRCH);
+	  res = -1;
+	}
+    }
+  return res;
+}
+
 extern "C" ssize_t
 _read (int fd, void *ptr, size_t len)
 {