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authorWaldemar Brodkorb <wbx@uclibc-ng.org>2018-03-19 19:23:33 +0100
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2018-03-22 19:14:01 +0100
commit91e21d25187d24bdd48875fb2544ec195ca2104a (patch)
tree826d8e12eb944a1e274f48b30e3ede3b983f8109 /libc/sysdeps/linux/hppa/vfork.S
parent8be3a69f1881cb87189164821c631fb398ea2b11 (diff)
hppa: fix runtime issues
Sync clone()/vfork() with GNU C Library. Allow CFI and fix strsignal() / tcsetattr().
Diffstat (limited to 'libc/sysdeps/linux/hppa/vfork.S')
-rw-r--r--libc/sysdeps/linux/hppa/vfork.S82
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)