hppa: fix runtime issues

Sync clone()/vfork() with GNU C Library.
Allow CFI and fix strsignal() / tcsetattr().

1 files changed, 82 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/hppa/vfork.S b/libc/sysdeps/linux/hppa/vfork.S
new file mode 100644
index 000000000..9d0706361
--- /dev/null
+++ b/libc/sysdeps/linux/hppa/vfork.S
@@ -0,0 +1,82 @@
+/* Copyright (C) 2005-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#define _ERRNO_H        1
+#include <bits/errno.h>
+
+/* Clone the calling process, but without copying the whole address space.
+   The calling process is suspended until the new process exits or is
+   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
+   and the process ID of the new process to the old process.  */
+
+.Lthread_start:						ASM_LINE_SEP
+
+	/* r26, r25, r24, r23 are free since vfork has no arguments */
+ENTRY(__vfork)
+	/* We must not create a frame. When the child unwinds to call
+	   exec it will clobber the same frame that the parent
+	   needs to unwind.  */
+
+	/* Save the PIC register. */
+#ifdef __PIC__
+	copy	%r19, %r25	/* parent */
+#endif
+
+	/* Syscall saves and restores all register states */
+	ble	0x100(%sr2,%r0)
+	ldi	__NR_vfork,%r20
+
+	/* Check for error */
+	ldi	-4096,%r1
+	comclr,>>= %r1,%ret0,%r0        /* Note: unsigned compare. */
+	b,n	.Lerror
+
+	/* Return, and DO NOT restore rp. The child may have called
+	   functions that updated the frame's rp. This works because
+	   the kernel ensures rp is preserved across the vfork
+	   syscall.  */
+	bv,n	%r0(%rp)
+
+.Lerror:
+	/* Now we need a stack to call a function. We are assured
+	   that there is no child now, so it's safe to create
+	   a frame.  */
+	stw	%rp, -20(%sp)
+	.cfi_offset 2, -20
+	stwm	%r3, 64(%sp)
+	.cfi_def_cfa_offset -64
+	.cfi_offset 3, 0
+	stw	%sp, -4(%sp)
+
+	sub	%r0,%ret0,%r3
+	SYSCALL_ERROR_HANDLER
+	/* Restore the PIC register (in delay slot) on error */
+#ifdef __PIC__
+	copy	%r25, %r19    /* parent */
+#else
+	nop
+#endif
+	/* Write syscall return into errno location */
+	stw	%r3, 0(%ret0)
+	ldw	-84(%sp), %rp
+	bv	%r0(%rp)
+	ldwm	-64(%sp), %r3
+
+PSEUDO_END (__vfork)
+libc_hidden_def(vfork)
+
+weak_alias (__vfork, vfork)