1/* libunwind - a platform-independent unwind library
2   Copyright (C) 2001-2005 Hewlett-Packard Co
3   Copyright (C) 2007 David Mosberger-Tang
4	Contributed by David Mosberger-Tang <dmosberger@gmail.com>
5
6This file is part of libunwind.
7
8Permission is hereby granted, free of charge, to any person obtaining
9a copy of this software and associated documentation files (the
10"Software"), to deal in the Software without restriction, including
11without limitation the rights to use, copy, modify, merge, publish,
12distribute, sublicense, and/or sell copies of the Software, and to
13permit persons to whom the Software is furnished to do so, subject to
14the following conditions:
15
16The above copyright notice and this permission notice shall be
17included in all copies or substantial portions of the Software.
18
19THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
23LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
24OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
25WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
26
27/* This files contains libunwind-internal definitions which are
28   subject to frequent change and are not to be exposed to
29   libunwind-users.  */
30
31#ifndef libunwind_i_h
32#define libunwind_i_h
33
34#ifdef HAVE_CONFIG_H
35# include "config.h"
36#endif
37
38#include "compiler.h"
39
40#ifdef HAVE___THREAD
41  /* For now, turn off per-thread caching.  It uses up too much TLS
42     memory per thread even when the thread never uses libunwind at
43     all.  */
44# undef HAVE___THREAD
45#endif
46
47/* Platform-independent libunwind-internal declarations.  */
48
49#include <sys/types.h>	/* HP-UX needs this before include of pthread.h */
50
51#include <assert.h>
52#include <libunwind.h>
53#include <pthread.h>
54#include <signal.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58#include <sys/mman.h>
59
60#if defined(HAVE_ELF_H)
61# include <elf.h>
62#elif defined(HAVE_SYS_ELF_H)
63# include <sys/elf.h>
64#else
65# error Could not locate <elf.h>
66#endif
67
68#if defined(HAVE_ENDIAN_H)
69# include <endian.h>
70#elif defined(HAVE_SYS_ENDIAN_H)
71# include <sys/endian.h>
72#else
73# define __LITTLE_ENDIAN	1234
74# define __BIG_ENDIAN		4321
75# if defined(__hpux)
76#   define __BYTE_ORDER __BIG_ENDIAN
77# elif defined(__QNX__)
78#   if defined(__BIGENDIAN__)
79#     define __BYTE_ORDER __BIG_ENDIAN
80#   elif defined(__LITTLEENDIAN__)
81#     define __BYTE_ORDER __LITTLE_ENDIAN
82#   else
83#     error Host has unknown byte-order.
84#   endif
85# else
86#   error Host has unknown byte-order.
87# endif
88#endif
89
90#if defined(HAVE__BUILTIN_UNREACHABLE)
91# define unreachable() __builtin_unreachable()
92#else
93# define unreachable() do { } while (1)
94#endif
95
96#ifdef DEBUG
97# define UNW_DEBUG	1
98#else
99# define UNW_DEBUG	0
100#endif
101
102/* Make it easy to write thread-safe code which may or may not be
103   linked against libpthread.  The macros below can be used
104   unconditionally and if -lpthread is around, they'll call the
105   corresponding routines otherwise, they do nothing.  */
106
107#pragma weak pthread_mutex_init
108#pragma weak pthread_mutex_lock
109#pragma weak pthread_mutex_unlock
110
111#define mutex_init(l)							\
112	(pthread_mutex_init != NULL ? pthread_mutex_init ((l), NULL) : 0)
113#define mutex_lock(l)							\
114	(pthread_mutex_lock != NULL ? pthread_mutex_lock (l) : 0)
115#define mutex_unlock(l)							\
116	(pthread_mutex_unlock != NULL ? pthread_mutex_unlock (l) : 0)
117
118#ifdef HAVE_ATOMIC_OPS_H
119# include <atomic_ops.h>
120static inline int
121cmpxchg_ptr (void *addr, void *old, void *new)
122{
123  union
124    {
125      void *vp;
126      AO_t *aop;
127    }
128  u;
129
130  u.vp = addr;
131  return AO_compare_and_swap(u.aop, (AO_t) old, (AO_t) new);
132}
133# define fetch_and_add1(_ptr)		AO_fetch_and_add1(_ptr)
134# define fetch_and_add(_ptr, value)	AO_fetch_and_add(_ptr, value)
135   /* GCC 3.2.0 on HP-UX crashes on cmpxchg_ptr() */
136#  if !(defined(__hpux) && __GNUC__ == 3 && __GNUC_MINOR__ == 2)
137#   define HAVE_CMPXCHG
138#  endif
139# define HAVE_FETCH_AND_ADD
140#elif defined(HAVE_SYNC_ATOMICS) || defined(HAVE_IA64INTRIN_H)
141# ifdef HAVE_IA64INTRIN_H
142#  include <ia64intrin.h>
143# endif
144static inline int
145cmpxchg_ptr (void *addr, void *old, void *new)
146{
147  union
148    {
149      void *vp;
150      long *vlp;
151    }
152  u;
153
154  u.vp = addr;
155  return __sync_bool_compare_and_swap(u.vlp, (long) old, (long) new);
156}
157# define fetch_and_add1(_ptr)		__sync_fetch_and_add(_ptr, 1)
158# define fetch_and_add(_ptr, value)	__sync_fetch_and_add(_ptr, value)
159# define HAVE_CMPXCHG
160# define HAVE_FETCH_AND_ADD
161#endif
162#define atomic_read(ptr)	(*(ptr))
163
164#define UNWI_OBJ(fn)	  UNW_PASTE(UNW_PREFIX,UNW_PASTE(I,fn))
165#define UNWI_ARCH_OBJ(fn) UNW_PASTE(UNW_PASTE(UNW_PASTE(_UI,UNW_TARGET),_), fn)
166
167#define unwi_full_mask    UNWI_ARCH_OBJ(full_mask)
168
169/* Type of a mask that can be used to inhibit preemption.  At the
170   userlevel, preemption is caused by signals and hence sigset_t is
171   appropriate.  In constrast, the Linux kernel uses "unsigned long"
172   to hold the processor "flags" instead.  */
173typedef sigset_t intrmask_t;
174
175extern intrmask_t unwi_full_mask;
176
177/* Silence compiler warnings about variables which are used only if libunwind
178   is configured in a certain way */
179static inline void mark_as_used(void *v UNUSED) {
180}
181
182#if defined(CONFIG_BLOCK_SIGNALS)
183# define SIGPROCMASK(how, new_mask, old_mask) \
184  sigprocmask((how), (new_mask), (old_mask))
185#else
186# define SIGPROCMASK(how, new_mask, old_mask) mark_as_used(old_mask)
187#endif
188
189/* ANDROID support update. */
190#define __lock_acquire_internal(l, m, acquire_func)	\
191do {							\
192  SIGPROCMASK (SIG_SETMASK, &unwi_full_mask, &(m));	\
193  acquire_func (l);					\
194} while (0)
195#define __lock_release_internal(l, m, release_func)	\
196do {							\
197  release_func (l);					\
198  SIGPROCMASK (SIG_SETMASK, &(m), NULL);		\
199} while (0)
200
201#define lock_rdwr_var(name)				\
202  pthread_rwlock_t name
203#define lock_rdwr_init(l)	pthread_rwlock_init (l, NULL)
204#define lock_rdwr_wr_acquire(l, m)			\
205  __lock_acquire_internal(l, m, pthread_rwlock_wrlock)
206#define lock_rdwr_rd_acquire(l, m)			\
207  __lock_acquire_internal(l, m, pthread_rwlock_rdlock)
208#define lock_rdwr_release(l, m)				\
209  __lock_release_internal(l, m, pthread_rwlock_unlock)
210
211#define lock_var(name) \
212  pthread_mutex_t name
213#define define_lock(name) \
214  lock_var (name) = PTHREAD_MUTEX_INITIALIZER
215#define lock_init(l)		mutex_init (l)
216#define lock_acquire(l,m)				\
217  __lock_acquire_internal(l, m, mutex_lock)
218#define lock_release(l,m)			\
219  __lock_release_internal(l, m, mutex_unlock)
220/* End of ANDROID update. */
221
222#define SOS_MEMORY_SIZE 16384	/* see src/mi/mempool.c */
223
224#ifndef MAP_ANONYMOUS
225# define MAP_ANONYMOUS MAP_ANON
226#endif
227#define GET_MEMORY(mem, size)				    		    \
228do {									    \
229  /* Hopefully, mmap() goes straight through to a system call stub...  */   \
230  mem = mmap (NULL, size, PROT_READ | PROT_WRITE,			    \
231	      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);			    \
232  if (mem == MAP_FAILED)						    \
233    mem = NULL;								    \
234} while (0)
235
236#define unwi_find_dynamic_proc_info	UNWI_OBJ(find_dynamic_proc_info)
237#define unwi_extract_dynamic_proc_info	UNWI_OBJ(extract_dynamic_proc_info)
238#define unwi_put_dynamic_unwind_info	UNWI_OBJ(put_dynamic_unwind_info)
239#define unwi_dyn_remote_find_proc_info	UNWI_OBJ(dyn_remote_find_proc_info)
240#define unwi_dyn_remote_put_unwind_info	UNWI_OBJ(dyn_remote_put_unwind_info)
241#define unwi_dyn_validate_cache		UNWI_OBJ(dyn_validate_cache)
242
243extern int unwi_find_dynamic_proc_info (unw_addr_space_t as,
244					unw_word_t ip,
245					unw_proc_info_t *pi,
246					int need_unwind_info, void *arg);
247extern int unwi_extract_dynamic_proc_info (unw_addr_space_t as,
248					   unw_word_t ip,
249					   unw_proc_info_t *pi,
250					   unw_dyn_info_t *di,
251					   int need_unwind_info,
252					   void *arg);
253extern void unwi_put_dynamic_unwind_info (unw_addr_space_t as,
254					  unw_proc_info_t *pi, void *arg);
255
256/* These handle the remote (cross-address-space) case of accessing
257   dynamic unwind info. */
258
259extern int unwi_dyn_remote_find_proc_info (unw_addr_space_t as,
260					   unw_word_t ip,
261					   unw_proc_info_t *pi,
262					   int need_unwind_info,
263					   void *arg);
264extern void unwi_dyn_remote_put_unwind_info (unw_addr_space_t as,
265					     unw_proc_info_t *pi,
266					     void *arg);
267extern int unwi_dyn_validate_cache (unw_addr_space_t as, void *arg);
268
269extern unw_dyn_info_list_t _U_dyn_info_list;
270extern pthread_mutex_t _U_dyn_info_list_lock;
271
272#if UNW_DEBUG
273# define unwi_debug_level		UNWI_ARCH_OBJ(debug_level)
274extern long unwi_debug_level;
275
276# ifdef ANDROID
277# define LOG_TAG "libunwind"
278# include <log/log.h>
279
280# define Debug(level, format, ...)					\
281do {									\
282  if (unwi_debug_level >= (level))					\
283    { 									\
284      ALOGI("%*c>%s: " format, ((level) <= 16) ? (level) : 16, ' ',	\
285            __FUNCTION__, ##__VA_ARGS__);				\
286    } 									\
287} while (0)
288# define Dprintf(format, ...) ALOGI(format, ##__VA_ARGS__);
289#else
290# include <stdio.h>
291# define Debug(level,format...)						\
292do {									\
293  if (unwi_debug_level >= level)					\
294    {									\
295      int _n = level;							\
296      if (_n > 16)							\
297	_n = 16;							\
298      fprintf (stderr, "%*c>%s: ", _n, ' ', __FUNCTION__);		\
299      fprintf (stderr, format);						\
300    }									\
301} while (0)
302# define Dprintf(format...) 	    fprintf (stderr, format)
303# ifdef __GNUC__
304#  undef inline
305#  define inline	UNUSED
306# endif
307# endif
308#else
309# define Debug(level,format...)
310# define Dprintf(format...)
311#endif
312
313static ALWAYS_INLINE int
314print_error (const char *string)
315{
316  return write (2, string, strlen (string));
317}
318
319#define mi_init		UNWI_ARCH_OBJ(mi_init)
320
321extern void mi_init (void);	/* machine-independent initializations */
322extern unw_word_t _U_dyn_info_list_addr (void);
323
324/* This is needed/used by ELF targets only.  */
325
326struct elf_image
327  {
328    void *image;		/* pointer to mmap'd image */
329    size_t size;		/* (file-) size of the image */
330  };
331
332struct elf_dyn_info
333  {
334    /* ANDROID support update.*/
335    /* Removed: struct elf_image ei; */
336    /* End of ANDROID update. */
337    unw_dyn_info_t di_cache;
338    unw_dyn_info_t di_debug;    /* additional table info for .debug_frame */
339#if UNW_TARGET_IA64
340    unw_dyn_info_t ktab;
341#endif
342#if UNW_TARGET_ARM
343    unw_dyn_info_t di_arm;      /* additional table info for .ARM.exidx */
344#endif
345  };
346
347static inline void invalidate_edi (struct elf_dyn_info *edi)
348{
349  /* ANDROID support update.*/
350  /* Removed: if (edi->ei.image) */
351  /*            munmap (edi->ei.image, edi->ei.size); */
352  /* End of ANDROID update. */
353  memset (edi, 0, sizeof (*edi));
354  edi->di_cache.format = -1;
355  edi->di_debug.format = -1;
356#if UNW_TARGET_ARM
357  edi->di_arm.format = -1;
358#endif
359}
360
361
362/* Provide a place holder for architecture to override for fast access
363   to memory when known not to need to validate and know the access
364   will be local to the process. A suitable override will improve
365   unw_tdep_trace() performance in particular. */
366#define ACCESS_MEM_FAST(ret,validate,cur,addr,to) \
367  do { (ret) = dwarf_get ((cur), DWARF_MEM_LOC ((cur), (addr)), &(to)); } \
368  while (0)
369
370/* Define GNU and processor specific values for the Phdr p_type field in case
371   they aren't defined by <elf.h>.  */
372#ifndef PT_GNU_EH_FRAME
373# define PT_GNU_EH_FRAME	0x6474e550
374#endif /* !PT_GNU_EH_FRAME */
375#ifndef PT_ARM_EXIDX
376# define PT_ARM_EXIDX		0x70000001	/* ARM unwind segment */
377#endif /* !PT_ARM_EXIDX */
378
379#include "tdep/libunwind_i.h"
380
381#ifndef tdep_get_func_addr
382# define tdep_get_func_addr(as,addr,v)		(*(v) = addr, 0)
383#endif
384
385#define UNW_ALIGN(x,a) (((x)+(a)-1UL)&~((a)-1UL))
386
387#endif /* libunwind_i_h */
388