libbacktrace/internal.h

   1 /* internal.h -- Internal header file for stack backtrace library.
   2    Copyright (C) 2012-2017 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, size_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 /* Read initial debug data from a descriptor, and set the
 261    fileline_data, syminfo_fn, and syminfo_data fields of STATE.
 262    Return the fileln_fn field in *FILELN_FN--this is done this way so
 263    that the synchronization code is only implemented once.  This is
 264    called after the descriptor has first been opened.  It will close
 265    the descriptor if it is no longer needed.  Returns 1 on success, 0
 266    on error.  There will be multiple implementations of this function,
 267    for different file formats.  Each system will compile the
 268    appropriate one.  */
 269
 270 extern int backtrace_initialize (struct backtrace_state *state,
 271                                  const char *filename,
 272                                  int descriptor,
 273                                  backtrace_error_callback error_callback,
 274                                  void *data,
 275                                  fileline *fileline_fn);
 276
 277 /* Add file/line information for a DWARF module.  */
 278
 279 extern int backtrace_dwarf_add (struct backtrace_state *state,
 280                                 uintptr_t base_address,
 281                                 const unsigned char* dwarf_info,
 282                                 size_t dwarf_info_size,
 283                                 const unsigned char *dwarf_line,
 284                                 size_t dwarf_line_size,
 285                                 const unsigned char *dwarf_abbrev,
 286                                 size_t dwarf_abbrev_size,
 287                                 const unsigned char *dwarf_ranges,
 288                                 size_t dwarf_range_size,
 289                                 const unsigned char *dwarf_str,
 290                                 size_t dwarf_str_size,
 291                                 int is_bigendian,
 292                                 backtrace_error_callback error_callback,
 293                                 void *data, fileline *fileline_fn);
 294
 295 /* A test-only hook for elf_uncompress_zdebug.  */
 296
 297 extern int backtrace_uncompress_zdebug (struct backtrace_state *,
 298                                         const unsigned char *compressed,
 299                                         size_t compressed_size,
 300                                         backtrace_error_callback, void *data,
 301                                         unsigned char **uncompressed,
 302                                         size_t *uncompressed_size);
 303
 304 #endif