diff options
Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/hppa/makecontext.c')
| -rw-r--r-- | ports/sysdeps/unix/sysv/linux/hppa/makecontext.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/hppa/makecontext.c b/ports/sysdeps/unix/sysv/linux/hppa/makecontext.c new file mode 100644 index 0000000000..11039d69b3 --- /dev/null +++ b/ports/sysdeps/unix/sysv/linux/hppa/makecontext.c @@ -0,0 +1,100 @@ +/* Create new context. + Copyright (C) 2008, 2010 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Helge Deller <deller@gmx.de>, 2008. + + 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 <libintl.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <sysdep.h> +#include <ucontext.h> + +/* POSIX only supports integer arguments. */ + +/* Stack must be 64-byte aligned at all times. */ +#define STACK_ALIGN 64 +/* Size of frame marker in unsigned long words. */ +#define FRAME_SIZE_UL 8 +/* Size of frame marker in bytes. */ +#define FRAME_SIZE_BYTES (8 * sizeof(unsigned long)) +/* Size of X arguments in bytes. */ +#define ARGS(x) (x * sizeof(unsigned long)) + +void +__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...) +{ + unsigned long *sp, *osp; + va_list ap; + int i; + + /* Create a 64-byte aligned frame to store args. Use ss_sp if + it is available, otherwise be robust and use the currently + saved stack pointer. */ + if (ucp->uc_stack.ss_sp && ucp->uc_stack.ss_size) + osp = (unsigned long *)ucp->uc_stack.ss_sp; + else + osp = (unsigned long *)ucp->uc_mcontext.sc_gr[30]; + + sp = (unsigned long *)((((unsigned long) osp) + + FRAME_SIZE_BYTES + ARGS(argc) + STACK_ALIGN) + & ~(STACK_ALIGN - 1)); + + /* Use new frame. */ + ucp->uc_mcontext.sc_gr[30] = ((unsigned long) sp); + + /* Finish frame setup. */ + if (ucp->uc_link) + { + /* Returning to the next context and next frame. */ + sp[-4/sizeof(unsigned long)] = ucp->uc_link->uc_mcontext.sc_gr[30]; + sp[-20/sizeof(unsigned long)] = ucp->uc_link->uc_mcontext.sc_gr[2]; + } + else + { + /* This is the main context. No frame marker, and no return address. */ + sp[-4/sizeof(unsigned long)] = 0x0; + sp[-20/sizeof(unsigned long)] = 0x0; + } + + /* Store address to jump to. */ + ucp->uc_mcontext.sc_gr[2] = (unsigned long) func; + + /* Process arguments. */ + va_start (ap, argc); + for (i = 0; i < argc; ++i) + { + if (i < 4) + { + ucp->uc_mcontext.sc_gr[26-i] = va_arg (ap, int); + continue; + } + + if ((i < 8) && (sizeof(unsigned long) == 8)) + { + /* 64bit: r19-r22 are arg7-arg4. */ + ucp->uc_mcontext.sc_gr[22+4-i] = va_arg (ap, int); + continue; + } + + /* All other arguments go on the stack. */ + sp[-1 * (FRAME_SIZE_UL + 1 + i)] = va_arg (ap, int); + } + va_end (ap); +} +weak_alias(__makecontext, makecontext) + |