gdb/solist.h

   1 /* Shared library declarations for GDB, the GNU Debugger.
   2    Copyright (C) 1990-2023 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef SOLIST_H
  20 #define SOLIST_H
  21
  22 #define SO_NAME_MAX_PATH_SIZE 512       /* FIXME: Should be dynamic */
  23 /* For domain_enum domain.  */
  24 #include "symtab.h"
  25 #include "gdb_bfd.h"
  26 #include "target-section.h"
  27
  28 /* Base class for target-specific link map information.  */
  29
  30 struct lm_info
  31 {
  32   lm_info () = default;
  33   lm_info (const lm_info &) = default;
  34   virtual ~lm_info () = 0;
  35 };
  36
  37 using lm_info_up = std::unique_ptr<lm_info>;
  38
  39 struct so_list
  40 {
  41   /* Free symbol-file related contents of SO and reset for possible reloading
  42      of SO.  If we have opened a BFD for SO, close it.  If we have placed SO's
  43      sections in some target's section table, the caller is responsible for
  44      removing them.
  45
  46      This function doesn't mess with objfiles at all.  If there is an
  47      objfile associated with SO that needs to be removed, the caller is
  48      responsible for taking care of that.  */
  49   void clear () ;
  50
  51   /* The following fields of the structure come directly from the
  52      dynamic linker's tables in the inferior, and are initialized by
  53      current_sos.  */
  54
  55   struct so_list *next = nullptr;       /* next structure in linked list */
  56
  57   /* A pointer to target specific link map information.  Often this
  58      will be a copy of struct link_map from the user process, but
  59      it need not be; it can be any collection of data needed to
  60      traverse the dynamic linker's data structures.  */
  61   lm_info_up lm_info;
  62
  63   /* Shared object file name, exactly as it appears in the
  64      inferior's link map.  This may be a relative path, or something
  65      which needs to be looked up in LD_LIBRARY_PATH, etc.  We use it
  66      to tell which entries in the inferior's dynamic linker's link
  67      map we've already loaded.  */
  68   char so_original_name[SO_NAME_MAX_PATH_SIZE] {};
  69
  70   /* Shared object file name, expanded to something GDB can open.  */
  71   char so_name[SO_NAME_MAX_PATH_SIZE] {};
  72
  73   /* The following fields of the structure are built from
  74      information gathered from the shared object file itself, and
  75      are set when we actually add it to our symbol tables.
  76
  77      current_sos must initialize these fields to 0.  */
  78
  79   bfd *abfd = nullptr;
  80   char symbols_loaded = 0;      /* flag: symbols read in yet?  */
  81
  82   /* objfile with symbols for a loaded library.  Target memory is read from
  83      ABFD.  OBJFILE may be NULL either before symbols have been loaded, if
  84      the file cannot be found or after the command "nosharedlibrary".  */
  85   struct objfile *objfile = nullptr;
  86
  87   target_section_table *sections = nullptr;
  88
  89   /* Record the range of addresses belonging to this shared library.
  90      There may not be just one (e.g. if two segments are relocated
  91      differently).  This is used for "info sharedlibrary" and
  92      the MI command "-file-list-shared-libraries".  The latter has a format
  93      that supports outputting multiple segments once the related code
  94      supports them.  */
  95   CORE_ADDR addr_low = 0, addr_high = 0;
  96 };
  97
  98 struct target_so_ops
  99 {
 100   /* Adjust the section binding addresses by the base address at
 101      which the object was actually mapped.  */
 102   void (*relocate_section_addresses) (so_list &so, target_section *);
 103
 104   /* Reset private data structures associated with SO.
 105      This is called when SO is about to be reloaded.
 106      It is also called when SO is about to be freed.  */
 107   void (*clear_so) (const so_list &so);
 108
 109   /* Free private data structures associated to PSPACE.  This method
 110      should not free resources associated to individual so_list entries,
 111      those are cleared by the clear_so method.  */
 112   void (*clear_solib) (program_space *pspace);
 113
 114   /* Target dependent code to run after child process fork.  */
 115   void (*solib_create_inferior_hook) (int from_tty);
 116
 117   /* Construct a list of the currently loaded shared objects.  This
 118      list does not include an entry for the main executable file.
 119
 120      Note that we only gather information directly available from the
 121      inferior --- we don't examine any of the shared library files
 122      themselves.  The declaration of `struct so_list' says which fields
 123      we provide values for.  */
 124   struct so_list *(*current_sos) (void);
 125
 126   /* Find, open, and read the symbols for the main executable.  If
 127      FROM_TTY is non-zero, allow messages to be printed.  */
 128   int (*open_symbol_file_object) (int from_ttyp);
 129
 130   /* Determine if PC lies in the dynamic symbol resolution code of
 131      the run time loader.  */
 132   int (*in_dynsym_resolve_code) (CORE_ADDR pc);
 133
 134   /* Find and open shared library binary file.  */
 135   gdb_bfd_ref_ptr (*bfd_open) (const char *pathname);
 136
 137   /* Optional extra hook for finding and opening a solib.
 138      If TEMP_PATHNAME is non-NULL: If the file is successfully opened a
 139      pointer to a malloc'd and realpath'd copy of SONAME is stored there,
 140      otherwise NULL is stored there.  */
 141   int (*find_and_open_solib) (const char *soname,
 142                               unsigned o_flags,
 143                               gdb::unique_xmalloc_ptr<char> *temp_pathname);
 144
 145   /* Given two so_list objects, one from the GDB thread list
 146      and another from the list returned by current_sos, return 1
 147      if they represent the same library.
 148      Falls back to using strcmp on so_original_name field when set
 149      to NULL.  */
 150   int (*same) (const so_list &gdb, const so_list &inferior);
 151
 152   /* Return whether a region of memory must be kept in a core file
 153      for shared libraries loaded before "gcore" is used to be
 154      handled correctly when the core file is loaded.  This only
 155      applies when the section would otherwise not be kept in the
 156      core file (in particular, for readonly sections).  */
 157   int (*keep_data_in_core) (CORE_ADDR vaddr,
 158                             unsigned long size);
 159
 160   /* Enable or disable optional solib event breakpoints as
 161      appropriate.  This should be called whenever
 162      stop_on_solib_events is changed.  This pointer can be
 163      NULL, in which case no enabling or disabling is necessary
 164      for this target.  */
 165   void (*update_breakpoints) (void);
 166
 167   /* Target-specific processing of solib events that will be
 168      performed before solib_add is called.  This pointer can be
 169      NULL, in which case no specific preprocessing is necessary
 170      for this target.  */
 171   void (*handle_event) (void);
 172 };
 173
 174 using so_list_range = next_range<so_list>;
 175
 176 /* Free the memory associated with a (so_list *).  */
 177 void free_so (so_list &so);
 178
 179 /* A deleter that calls free_so.  */
 180 struct so_deleter
 181 {
 182   void operator() (struct so_list *so) const
 183   {
 184     free_so (*so);
 185   }
 186 };
 187
 188 /* A unique pointer to a so_list.  */
 189 typedef std::unique_ptr<so_list, so_deleter> so_list_up;
 190
 191 /* Find main executable binary file.  */
 192 extern gdb::unique_xmalloc_ptr<char> exec_file_find (const char *in_pathname,
 193                                                      int *fd);
 194
 195 /* Find shared library binary file.  */
 196 extern gdb::unique_xmalloc_ptr<char> solib_find (const char *in_pathname,
 197                                                  int *fd);
 198
 199 /* Open BFD for shared library file.  */
 200 extern gdb_bfd_ref_ptr solib_bfd_fopen (const char *pathname, int fd);
 201
 202 /* Find solib binary file and open it.  */
 203 extern gdb_bfd_ref_ptr solib_bfd_open (const char *in_pathname);
 204
 205 #endif