gdb/minsyms.h

   1 /* Minimal symbol table definitions for GDB.
   2
   3    Copyright (C) 2011-2012 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef MINSYMS_H
  21 #define MINSYMS_H
  22
  23 /* This header declares most of the API for dealing with minimal
  24    symbols and minimal symbol tables.  A few things are declared
  25    elsewhere; see below.
  26
  27    A minimal symbol is a symbol for which there is no direct debug
  28    information.  For example, for an ELF binary, minimal symbols are
  29    created from the ELF symbol table.
  30
  31    For the definition of the minimal symbol structure, see struct
  32    minimal_symbol in symtab.h.
  33
  34    Minimal symbols are stored in tables attached to an objfile; see
  35    objfiles.h for details.  Code should generally treat these tables
  36    as opaque and use functions provided by minsyms.c to inspect them.
  37 */
  38
  39 /* Prepare to start collecting minimal symbols.  This should be called
  40    by a symbol reader to initialize the minimal symbol module.
  41    Currently, minimal symbol table creation is not reentrant; it
  42    relies on global (static) variables in minsyms.c.  */
  43
  44 void init_minimal_symbol_collection (void);
  45
  46 /* Return a cleanup which is used to clean up the global state left
  47    over by minimal symbol creation.  After calling
  48    init_minimal_symbol_collection, a symbol reader should call this
  49    function.  Then, after all minimal symbols have been read,
  50    regardless of whether they are installed or not, the cleanup
  51    returned by this function should be run.  */
  52
  53 struct cleanup *make_cleanup_discard_minimal_symbols (void);
  54
  55 /* Record a new minimal symbol.  This is the "full" entry point;
  56    simpler convenience entry points are also provided below.
  57
  58    This returns a new minimal symbol.  It is ok to modify the returned
  59    minimal symbol (though generally not necessary).  It is not ok,
  60    though, to stash the pointer anywhere; as minimal symbols may be
  61    moved after creation.  The memory for the returned minimal symbol
  62    is still owned by the minsyms.c code, and should not be freed.
  63
  64    Arguments are:
  65
  66    NAME - the symbol's name
  67    NAME_LEN - the length of the name
  68    COPY_NAME - if true, the minsym code must make a copy of NAME.  If
  69    false, then NAME must be NUL-terminated, and must have a lifetime
  70    that is at least as long as OBJFILE's lifetime.
  71    ADDRESS - the address of the symbol
  72    MS_TYPE - the type of the symbol
  73    SECTION - the symbol's section
  74    BFD_SECTION - the symbol's BFD section; used to find the
  75    appropriate obj_section for the minimal symbol.  This can be NULL.
  76    OBJFILE - the objfile associated with the minimal symbol.  */
  77
  78 struct minimal_symbol *prim_record_minimal_symbol_full
  79     (const char *name,
  80      int name_len,
  81      int copy_name,
  82      CORE_ADDR address,
  83      enum minimal_symbol_type ms_type,
  84      int section,
  85      asection *bfd_section,
  86      struct objfile *objfile);
  87
  88 /* Like prim_record_minimal_symbol_full, but:
  89    - uses strlen to compute NAME_LEN,
  90    - passes COPY_NAME = 0,
  91    - passes SECTION = 0,
  92    - and passes BFD_SECTION = NULL.
  93
  94    This variant does not return the new symbol.  */
  95
  96 void prim_record_minimal_symbol (const char *, CORE_ADDR,
  97                                  enum minimal_symbol_type,
  98                                  struct objfile *);
  99
 100 /* Like prim_record_minimal_symbol_full, but:
 101    - uses strlen to compute NAME_LEN,
 102    - passes COPY_NAME = 0.  */
 103
 104 struct minimal_symbol *prim_record_minimal_symbol_and_info
 105     (const char *,
 106      CORE_ADDR,
 107      enum minimal_symbol_type,
 108      int section,
 109      asection *bfd_section,
 110      struct objfile *);
 111
 112 /* Install the minimal symbols that have been collected into the given
 113    objfile.  After this is called, the cleanup returned by
 114    make_cleanup_discard_minimal_symbols should be run in order to
 115    clean up global state.  */
 116
 117 void install_minimal_symbols (struct objfile *);
 118
 119 /* Create the terminating entry of OBJFILE's minimal symbol table.
 120    If OBJFILE->msymbols is zero, allocate a single entry from
 121    OBJFILE->objfile_obstack; otherwise, just initialize
 122    OBJFILE->msymbols[OBJFILE->minimal_symbol_count].  */
 123
 124 void terminate_minimal_symbol_table (struct objfile *objfile);
 125
 126 /* Sort all the minimal symbols in OBJFILE.  This should be only be
 127    called after relocating symbols; it ensures that the minimal
 128    symbols are properly sorted by address.  */
 129
 130 void msymbols_sort (struct objfile *objfile);
 131
 132 \f
 133
 134 /* Compute a hash code for the string argument.  */
 135
 136 unsigned int msymbol_hash (const char *);
 137
 138 /* Like msymbol_hash, but compute a hash code that is compatible with
 139    strcmp_iw.  */
 140
 141 unsigned int msymbol_hash_iw (const char *);
 142
 143 /* Compute the next hash value from previous HASH and the character C.  This
 144    is only a GDB in-memory computed value with no external files compatibility
 145    requirements.  */
 146
 147 #define SYMBOL_HASH_NEXT(hash, c)                       \
 148   ((hash) * 67 + tolower ((unsigned char) (c)) - 113)
 149
 150 \f
 151
 152 /* Return the objfile that holds the minimal symbol SYM.  Every
 153    minimal symbols is held by some objfile; this will never return
 154    NULL.  */
 155
 156 struct objfile *msymbol_objfile (struct minimal_symbol *sym);
 157
 158 \f
 159
 160 /* Look through all the current minimal symbol tables and find the
 161    first minimal symbol that matches NAME.  If OBJF is non-NULL, limit
 162    the search to that objfile.  If SFILE is non-NULL, the only file-scope
 163    symbols considered will be from that source file (global symbols are
 164    still preferred).  Returns a pointer to the minimal symbol that
 165    matches, or NULL if no match is found.  */
 166
 167 struct minimal_symbol *lookup_minimal_symbol (const char *,
 168                                               const char *,
 169                                               struct objfile *);
 170
 171 /* Find the minimal symbol named NAME, and return both the minsym
 172    struct and its objfile.  This only checks the linkage name.  Sets
 173    *OBJFILE_P and returns the minimal symbol, if it is found.  If it
 174    is not found, returns NULL.  */
 175
 176 struct minimal_symbol *lookup_minimal_symbol_and_objfile (const char *,
 177                                                           struct objfile **);
 178
 179 /* Look through all the current minimal symbol tables and find the
 180    first minimal symbol that matches NAME and has text type.  If OBJF
 181    is non-NULL, limit the search to that objfile.  Returns a pointer
 182    to the minimal symbol that matches, or NULL if no match is found.
 183
 184    This function only searches the mangled (linkage) names.  */
 185
 186 struct minimal_symbol *lookup_minimal_symbol_text (const char *,
 187                                                    struct objfile *);
 188
 189 /* Look through all the current minimal symbol tables and find the
 190    first minimal symbol that matches NAME and is a solib trampoline.
 191    If OBJF is non-NULL, limit the search to that objfile.  Returns a
 192    pointer to the minimal symbol that matches, or NULL if no match is
 193    found.
 194
 195    This function only searches the mangled (linkage) names.  */
 196
 197 struct minimal_symbol *lookup_minimal_symbol_solib_trampoline
 198     (const char *,
 199      struct objfile *);
 200
 201 /* Look through all the current minimal symbol tables and find the
 202    first minimal symbol that matches NAME and PC.  If OBJF is non-NULL,
 203    limit the search to that objfile.  Returns a pointer to the minimal
 204    symbol that matches, or NULL if no match is found.  */
 205
 206 struct minimal_symbol *lookup_minimal_symbol_by_pc_name
 207     (CORE_ADDR, const char *, struct objfile *);
 208
 209 /* Search through the minimal symbol table for each objfile and find
 210    the symbol whose address is the largest address that is still less
 211    than or equal to PC, and which matches SECTION.
 212
 213    If SECTION is NULL, this uses the result of find_pc_section
 214    instead.
 215
 216    Returns a pointer to the minimal symbol if such a symbol is found,
 217    or NULL if PC is not in a suitable range.  */
 218
 219 struct minimal_symbol *lookup_minimal_symbol_by_pc_section
 220     (CORE_ADDR,
 221      struct obj_section *);
 222
 223 /* Backward compatibility: search through the minimal symbol table
 224    for a matching PC (no section given).
 225
 226    This is a wrapper that calls lookup_minimal_symbol_by_pc_section
 227    with a NULL section argument.  */
 228
 229 struct minimal_symbol *lookup_minimal_symbol_by_pc (CORE_ADDR);
 230
 231 /* Check if PC is in a shared library trampoline code stub.
 232    Return minimal symbol for the trampoline entry or NULL if PC is not
 233    in a trampoline code stub.  */
 234
 235 struct minimal_symbol *lookup_solib_trampoline_symbol_by_pc (CORE_ADDR);
 236
 237 /* Iterate over all the minimal symbols in the objfile OBJF which
 238    match NAME.  Both the ordinary and demangled names of each symbol
 239    are considered.  The caller is responsible for canonicalizing NAME,
 240    should that need to be done.
 241
 242    For each matching symbol, CALLBACK is called with the symbol and
 243    USER_DATA as arguments.  */
 244
 245 void iterate_over_minimal_symbols (struct objfile *objf,
 246                                    const char *name,
 247                                    void (*callback) (struct minimal_symbol *,
 248                                                      void *),
 249                                    void *user_data);
 250
 251 #endif /* MINSYMS_H */