1 /* internal.h -- Internal header file for stack backtrace library.
2 Copyright (C) 2012-2020 Free Software Foundation, Inc.
3 Written by Ian Lance Taylor, Google.
4
5 Redistribution and use in source and binary forms, with or without
6 modification, are permitted provided that the following conditions are
7 met:
8
9 (1) Redistributions of source code must retain the above copyright
10 notice, this list of conditions and the following disclaimer.
11
12 (2) Redistributions in binary form must reproduce the above copyright
13 notice, this list of conditions and the following disclaimer in
14 the documentation and/or other materials provided with the
15 distribution.
16
17 (3) The name of the author may not be used to
18 endorse or promote products derived from this software without
19 specific prior written permission.
20
21 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24 DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
25 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
26 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
27 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
29 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
30 IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 POSSIBILITY OF SUCH DAMAGE. */
32
33 #ifndef BACKTRACE_INTERNAL_H
34 #define BACKTRACE_INTERNAL_H
35
36 /* We assume that <sys/types.h> and "backtrace.h" have already been
37 included. */
38
39 #ifndef GCC_VERSION
40 # define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
41 #endif
42
43 #if (GCC_VERSION < 2007)
44 # define __attribute__(x)
45 #endif
46
47 #ifndef ATTRIBUTE_UNUSED
48 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
49 #endif
50
51 #ifndef ATTRIBUTE_MALLOC
52 # if (GCC_VERSION >= 2096)
53 # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
54 # else
55 # define ATTRIBUTE_MALLOC
56 # endif
57 #endif
58
59 #ifndef HAVE_SYNC_FUNCTIONS
60
61 /* Define out the sync functions. These should never be called if
62 they are not available. */
63
64 #define __sync_bool_compare_and_swap(A, B, C) (abort(), 1)
65 #define __sync_lock_test_and_set(A, B) (abort(), 0)
66 #define __sync_lock_release(A) abort()
67
68 #endif /* !defined (HAVE_SYNC_FUNCTIONS) */
69
70 #ifdef HAVE_ATOMIC_FUNCTIONS
71
72 /* We have the atomic builtin functions. */
73
74 #define backtrace_atomic_load_pointer(p) \
75 __atomic_load_n ((p), __ATOMIC_ACQUIRE)
76 #define backtrace_atomic_load_int(p) \
77 __atomic_load_n ((p), __ATOMIC_ACQUIRE)
78 #define backtrace_atomic_store_pointer(p, v) \
79 __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
80 #define backtrace_atomic_store_size_t(p, v) \
81 __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
82 #define backtrace_atomic_store_int(p, v) \
83 __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
84
85 #else /* !defined (HAVE_ATOMIC_FUNCTIONS) */
86 #ifdef HAVE_SYNC_FUNCTIONS
87
88 /* We have the sync functions but not the atomic functions. Define
89 the atomic ones in terms of the sync ones. */
90
91 extern void *backtrace_atomic_load_pointer (void *);
92 extern int backtrace_atomic_load_int (int *);
93 extern void backtrace_atomic_store_pointer (void *, void *);
94 extern void backtrace_atomic_store_size_t (size_t *, size_t);
95 extern void backtrace_atomic_store_int (int *, int);
96
97 #else /* !defined (HAVE_SYNC_FUNCTIONS) */
98
99 /* We have neither the sync nor the atomic functions. These will
100 never be called. */
101
102 #define backtrace_atomic_load_pointer(p) (abort(), (void *) NULL)
103 #define backtrace_atomic_load_int(p) (abort(), 0)
104 #define backtrace_atomic_store_pointer(p, v) abort()
105 #define backtrace_atomic_store_size_t(p, v) abort()
106 #define backtrace_atomic_store_int(p, v) abort()
107
108 #endif /* !defined (HAVE_SYNC_FUNCTIONS) */
109 #endif /* !defined (HAVE_ATOMIC_FUNCTIONS) */
110
111 /* The type of the function that collects file/line information. This
112 is like backtrace_pcinfo. */
113
114 typedef int (*fileline) (struct backtrace_state *state, uintptr_t pc,
115 backtrace_full_callback callback,
116 backtrace_error_callback error_callback, void *data);
117
118 /* The type of the function that collects symbol information. This is
119 like backtrace_syminfo. */
120
121 typedef void (*syminfo) (struct backtrace_state *state, uintptr_t pc,
122 backtrace_syminfo_callback callback,
123 backtrace_error_callback error_callback, void *data);
124
125 /* What the backtrace state pointer points to. */
126
127 struct backtrace_state
128 {
129 /* The name of the executable. */
130 const char *filename;
131 /* Non-zero if threaded. */
132 int threaded;
133 /* The master lock for fileline_fn, fileline_data, syminfo_fn,
134 syminfo_data, fileline_initialization_failed and everything the
135 data pointers point to. */
136 void *lock;
137 /* The function that returns file/line information. */
138 fileline fileline_fn;
139 /* The data to pass to FILELINE_FN. */
140 void *fileline_data;
141 /* The function that returns symbol information. */
142 syminfo syminfo_fn;
143 /* The data to pass to SYMINFO_FN. */
144 void *syminfo_data;
145 /* Whether initializing the file/line information failed. */
146 int fileline_initialization_failed;
147 /* The lock for the freelist. */
148 int lock_alloc;
149 /* The freelist when using mmap. */
150 struct backtrace_freelist_struct *freelist;
151 };
152
153 /* Open a file for reading. Returns -1 on error. If DOES_NOT_EXIST
154 is not NULL, *DOES_NOT_EXIST will be set to 0 normally and set to 1
155 if the file does not exist. If the file does not exist and
156 DOES_NOT_EXIST is not NULL, the function will return -1 and will
157 not call ERROR_CALLBACK. On other errors, or if DOES_NOT_EXIST is
158 NULL, the function will call ERROR_CALLBACK before returning. */
159 extern int backtrace_open (const char *filename,
160 backtrace_error_callback error_callback,
161 void *data,
162 int *does_not_exist);
163
164 /* A view of the contents of a file. This supports mmap when
165 available. A view will remain in memory even after backtrace_close
166 is called on the file descriptor from which the view was
167 obtained. */
168
169 struct backtrace_view
170 {
171 /* The data that the caller requested. */
172 const void *data;
173 /* The base of the view. */
174 void *base;
175 /* The total length of the view. */
176 size_t len;
177 };
178
179 /* Create a view of SIZE bytes from DESCRIPTOR at OFFSET. Store the
180 result in *VIEW. Returns 1 on success, 0 on error. */
181 extern int backtrace_get_view (struct backtrace_state *state, int descriptor,
182 off_t offset, uint64_t size,
183 backtrace_error_callback error_callback,
184 void *data, struct backtrace_view *view);
185
186 /* Release a view created by backtrace_get_view. */
187 extern void backtrace_release_view (struct backtrace_state *state,
188 struct backtrace_view *view,
189 backtrace_error_callback error_callback,
190 void *data);
191
192 /* Close a file opened by backtrace_open. Returns 1 on success, 0 on
193 error. */
194
195 extern int backtrace_close (int descriptor,
196 backtrace_error_callback error_callback,
197 void *data);
198
199 /* Sort without using memory. */
200
201 extern void backtrace_qsort (void *base, size_t count, size_t size,
202 int (*compar) (const void *, const void *));
203
204 /* Allocate memory. This is like malloc. If ERROR_CALLBACK is NULL,
205 this does not report an error, it just returns NULL. */
206
207 extern void *backtrace_alloc (struct backtrace_state *state, size_t size,
208 backtrace_error_callback error_callback,
209 void *data) ATTRIBUTE_MALLOC;
210
211 /* Free memory allocated by backtrace_alloc. If ERROR_CALLBACK is
212 NULL, this does not report an error. */
213
214 extern void backtrace_free (struct backtrace_state *state, void *mem,
215 size_t size,
216 backtrace_error_callback error_callback,
217 void *data);
218
219 /* A growable vector of some struct. This is used for more efficient
220 allocation when we don't know the final size of some group of data
221 that we want to represent as an array. */
222
223 struct backtrace_vector
224 {
225 /* The base of the vector. */
226 void *base;
227 /* The number of bytes in the vector. */
228 size_t size;
229 /* The number of bytes available at the current allocation. */
230 size_t alc;
231 };
232
233 /* Grow VEC by SIZE bytes. Return a pointer to the newly allocated
234 bytes. Note that this may move the entire vector to a new memory
235 location. Returns NULL on failure. */
236
237 extern void *backtrace_vector_grow (struct backtrace_state *state, size_t size,
238 backtrace_error_callback error_callback,
239 void *data,
240 struct backtrace_vector *vec);
241
242 /* Finish the current allocation on VEC. Prepare to start a new
243 allocation. The finished allocation will never be freed. Returns
244 a pointer to the base of the finished entries, or NULL on
245 failure. */
246
247 extern void* backtrace_vector_finish (struct backtrace_state *state,
248 struct backtrace_vector *vec,
249 backtrace_error_callback error_callback,
250 void *data);
251
252 /* Release any extra space allocated for VEC. This may change
253 VEC->base. Returns 1 on success, 0 on failure. */
254
255 extern int backtrace_vector_release (struct backtrace_state *state,
256 struct backtrace_vector *vec,
257 backtrace_error_callback error_callback,
258 void *data);
259
260 /* Free the space managed by VEC. This will reset VEC. */
261
262 static inline void
backtrace_vector_free(struct backtrace_state * state,struct backtrace_vector * vec,backtrace_error_callback error_callback,void * data)263 backtrace_vector_free (struct backtrace_state *state,
264 struct backtrace_vector *vec,
265 backtrace_error_callback error_callback, void *data)
266 {
267 vec->alc += vec->size;
268 vec->size = 0;
269 backtrace_vector_release (state, vec, error_callback, data);
270 }
271
272 /* Read initial debug data from a descriptor, and set the
273 fileline_data, syminfo_fn, and syminfo_data fields of STATE.
274 Return the fileln_fn field in *FILELN_FN--this is done this way so
275 that the synchronization code is only implemented once. This is
276 called after the descriptor has first been opened. It will close
277 the descriptor if it is no longer needed. Returns 1 on success, 0
278 on error. There will be multiple implementations of this function,
279 for different file formats. Each system will compile the
280 appropriate one. */
281
282 extern int backtrace_initialize (struct backtrace_state *state,
283 const char *filename,
284 int descriptor,
285 backtrace_error_callback error_callback,
286 void *data,
287 fileline *fileline_fn);
288
289 /* An enum for the DWARF sections we care about. */
290
291 enum dwarf_section
292 {
293 DEBUG_INFO,
294 DEBUG_LINE,
295 DEBUG_ABBREV,
296 DEBUG_RANGES,
297 DEBUG_STR,
298 DEBUG_ADDR,
299 DEBUG_STR_OFFSETS,
300 DEBUG_LINE_STR,
301 DEBUG_RNGLISTS,
302
303 DEBUG_MAX
304 };
305
306 /* Data for the DWARF sections we care about. */
307
308 struct dwarf_sections
309 {
310 const unsigned char *data[DEBUG_MAX];
311 size_t size[DEBUG_MAX];
312 };
313
314 /* DWARF data read from a file, used for .gnu_debugaltlink. */
315
316 struct dwarf_data;
317
318 /* Add file/line information for a DWARF module. */
319
320 extern int backtrace_dwarf_add (struct backtrace_state *state,
321 uintptr_t base_address,
322 const struct dwarf_sections *dwarf_sections,
323 int is_bigendian,
324 struct dwarf_data *fileline_altlink,
325 backtrace_error_callback error_callback,
326 void *data, fileline *fileline_fn,
327 struct dwarf_data **fileline_entry);
328
329 /* A test-only hook for elf_uncompress_zdebug. */
330
331 extern int backtrace_uncompress_zdebug (struct backtrace_state *,
332 const unsigned char *compressed,
333 size_t compressed_size,
334 backtrace_error_callback, void *data,
335 unsigned char **uncompressed,
336 size_t *uncompressed_size);
337
338 #endif
339