diff options
Diffstat (limited to 'mach/setup-thread.c')
| -rw-r--r-- | mach/setup-thread.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/mach/setup-thread.c b/mach/setup-thread.c new file mode 100644 index 0000000000..a00edacdfd --- /dev/null +++ b/mach/setup-thread.c @@ -0,0 +1,99 @@ +/* Copyright (C) 1991, 1994, 1995 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <mach.h> +#include "thread_state.h" +#include <string.h> +#include <mach/machine/vm_param.h> +#include "sysdep.h" /* Defines stack direction. */ + +#define STACK_SIZE (16 * 1024 * 1024) /* 16MB, arbitrary. */ + +/* Give THREAD a stack and set it to run at PC when resumed. + If *STACK_SIZE is nonzero, that size of stack is allocated. + If *STACK_BASE is nonzero, that stack location is used. + If STACK_BASE is not null it is filled in with the chosen stack base. + If STACK_SIZE is not null it is filled in with the chosen stack size. + Regardless, an extra page of red zone is allocated off the end; this + is not included in *STACK_SIZE. */ + +kern_return_t +__mach_setup_thread (task_t task, thread_t thread, void *pc, + vm_address_t *stack_base, vm_size_t *stack_size) +{ + kern_return_t error; + struct machine_thread_state ts; + mach_msg_type_number_t tssize = MACHINE_THREAD_STATE_COUNT; + vm_address_t stack; + vm_size_t size; + int anywhere = 0; + + size = stack_size ? *stack_size ? : STACK_SIZE : STACK_SIZE; + + if (stack_base && *stack_base) + stack = *stack_base; + else if (size == STACK_SIZE) + { + /* Cthreads has a bug that makes its stack-probing code fail if + the stack is too low in memory. It's bad to try and fix it there + until cthreads is integrated into libc, so we'll just do it here + by requesting a high address. When the cthreads bug is fixed, + this assignment to STACK should be changed to 0, and the ANYWHERE + argument to vm_allocate should be changed to 0. This comment should + be left, however, in order to confuse people who wonder why its + here. (Though perhaps that last sentence (and this one) should + be deleted to maximize the effect.) */ +#ifdef STACK_GROWTH_DOWN + stack = VM_MAX_ADDRESS - size - __vm_page_size; +#else + stack = VM_MIN_ADDRESS; +#endif + } + else + anywhere = 1; + + if (error = __vm_allocate (task, &stack, size + __vm_page_size, anywhere)) + return error; + + if (stack_size) + *stack_size = size; + + memset (&ts, 0, sizeof (ts)); + MACHINE_THREAD_STATE_SET_PC (&ts, pc); +#ifdef STACK_GROWTH_DOWN + if (stack_base) + *stack_base = stack + __vm_page_size; + ts.SP = stack + __vm_page_size + size; +#elif defined (STACK_GROWTH_UP) + if (stack_base) + *stack_base = stack; + ts.SP = stack; + stack += size; +#else + #error stack direction unknown +#endif + + /* Create the red zone. */ + if (error = __vm_protect (task, stack, __vm_page_size, 0, VM_PROT_NONE)) + return error; + + return __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR, + (int *) &ts, tssize); +} + +weak_alias (__mach_setup_thread, mach_setup_thread) |