1 /* Generic definitions for dealing with Mach thread states.
2    Copyright (C) 1994-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 
20 /* Everything else is called `thread_state', but CMU's header file is
21    called `thread_status'.  Oh boy.  */
22 #include <mach/thread_status.h>
23 
24 /* The machine-dependent thread_state.h file can either define these
25    macros, or just define PC and SP to the register names.  */
26 
27 #ifndef MACHINE_THREAD_STATE_SET_PC
28 #define MACHINE_THREAD_STATE_SET_PC(ts, pc) \
29   ((ts)->PC = (unsigned long int) (pc))
30 #endif
31 #ifndef MACHINE_THREAD_STATE_SET_SP
32 #ifdef STACK_GROWTH_UP
33 #define MACHINE_THREAD_STATE_SET_SP(ts, stack, size) \
34   ((ts)->SP = (unsigned long int) (stack))
35 #else
36 #define MACHINE_THREAD_STATE_SET_SP(ts, stack, size) \
37   ((ts)->SP = (unsigned long int) (stack) + (size))
38 #endif
39 #endif
40 
41 /* This copies architecture-specific bits from the current thread to the new
42    thread state.  */
43 #ifndef MACHINE_THREAD_STATE_FIX_NEW
44 # define MACHINE_THREAD_STATE_FIX_NEW(ts)
45 #endif
46 
47 /* These functions are of use in machine-dependent signal trampoline
48    implementations.  */
49 
50 #include <string.h>		/* size_t, memcpy */
51 #include <mach/mach_interface.h> /* __thread_get_state */
52 
53 static inline int
machine_get_state(thread_t thread,struct machine_thread_all_state * state,int flavor,void * stateptr,void * scpptr,size_t size)54 machine_get_state (thread_t thread, struct machine_thread_all_state *state,
55 		   int flavor, void *stateptr, void *scpptr, size_t size)
56 {
57   if (state->set & (1 << flavor))
58     {
59       /* Copy the saved state.  */
60       memcpy (scpptr, stateptr, size);
61       return 1;
62     }
63   else
64     {
65       /* No one asked about this flavor of state before; fetch the state
66 	 directly from the kernel into the sigcontext.  */
67       mach_msg_type_number_t got = (size / sizeof (int));
68       return (! __thread_get_state (thread, flavor, scpptr, &got)
69 	      && got == (size / sizeof (int)));
70     }
71 }
72 
73 static inline int
machine_get_basic_state(thread_t thread,struct machine_thread_all_state * state)74 machine_get_basic_state (thread_t thread,
75 			 struct machine_thread_all_state *state)
76 {
77   mach_msg_type_number_t count;
78 
79   if (state->set & (1 << MACHINE_THREAD_STATE_FLAVOR))
80     return 1;
81 
82   count = MACHINE_THREAD_STATE_COUNT;
83   if (__thread_get_state (thread, MACHINE_THREAD_STATE_FLAVOR,
84 			  (natural_t *) &state->basic,
85 			  &count) != KERN_SUCCESS
86       || count != MACHINE_THREAD_STATE_COUNT)
87     /* What kind of thread?? */
88     return 0;			/* XXX */
89 
90   state->set |= 1 << MACHINE_THREAD_STATE_FLAVOR;
91   return 1;
92 }
93