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 shobj : intrusive_list_node<shobj>
  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   /* A pointer to target specific link map information.  Often this
  56      will be a copy of struct link_map from the user process, but
  57      it need not be; it can be any collection of data needed to
  58      traverse the dynamic linker's data structures.  */
  59   lm_info_up lm_info;
  60
  61   /* Shared object file name, exactly as it appears in the
  62      inferior's link map.  This may be a relative path, or something
  63      which needs to be looked up in LD_LIBRARY_PATH, etc.  We use it
  64      to tell which entries in the inferior's dynamic linker's link
  65      map we've already loaded.  */
  66   std::string so_original_name;
  67
  68   /* Shared object file name, expanded to something GDB can open.  */
  69   std::string so_name;
  70
  71   /* The following fields of the structure are built from
  72      information gathered from the shared object file itself, and
  73      are set when we actually add it to our symbol tables.
  74
  75      current_sos must initialize these fields to 0.  */
  76
  77   gdb_bfd_ref_ptr abfd;
  78   char symbols_loaded = 0;      /* flag: symbols read in yet?  */
  79
  80   /* objfile with symbols for a loaded library.  Target memory is read from
  81      ABFD.  OBJFILE may be NULL either before symbols have been loaded, if
  82      the file cannot be found or after the command "nosharedlibrary".  */
  83   struct objfile *objfile = nullptr;
  84
  85   std::vector<target_section> sections;
  86
  87   /* Record the range of addresses belonging to this shared library.
  88      There may not be just one (e.g. if two segments are relocated
  89      differently).  This is used for "info sharedlibrary" and
  90      the MI command "-file-list-shared-libraries".  The latter has a format
  91      that supports outputting multiple segments once the related code
  92      supports them.  */
  93   CORE_ADDR addr_low = 0, addr_high = 0;
  94 };
  95
  96 struct target_so_ops
  97 {
  98   /* Adjust the section binding addresses by the base address at
  99      which the object was actually mapped.  */
 100   void (*relocate_section_addresses) (shobj &so, target_section *);
 101
 102   /* Reset private data structures associated with SO.
 103      This is called when SO is about to be reloaded.
 104      It is also called when SO is about to be freed.  */
 105   void (*clear_so) (const shobj &so);
 106
 107   /* Free private data structures associated to PSPACE.  This method
 108      should not free resources associated to individual so_list entries,
 109      those are cleared by the clear_so method.  */
 110   void (*clear_solib) (program_space *pspace);
 111
 112   /* Target dependent code to run after child process fork.  */
 113   void (*solib_create_inferior_hook) (int from_tty);
 114
 115   /* Construct a list of the currently loaded shared objects.  This
 116      list does not include an entry for the main executable file.
 117
 118      Note that we only gather information directly available from the
 119      inferior --- we don't examine any of the shared library files
 120      themselves.  The declaration of `struct shobj' says which fields
 121      we provide values for.  */
 122   intrusive_list<shobj> (*current_sos) ();
 123
 124   /* Find, open, and read the symbols for the main executable.  If
 125      FROM_TTY is non-zero, allow messages to be printed.  */
 126   int (*open_symbol_file_object) (int from_ttyp);
 127
 128   /* Determine if PC lies in the dynamic symbol resolution code of
 129      the run time loader.  */
 130   int (*in_dynsym_resolve_code) (CORE_ADDR pc);
 131
 132   /* Find and open shared library binary file.  */
 133   gdb_bfd_ref_ptr (*bfd_open) (const char *pathname);
 134
 135   /* Optional extra hook for finding and opening a solib.
 136      If TEMP_PATHNAME is non-NULL: If the file is successfully opened a
 137      pointer to a malloc'd and realpath'd copy of SONAME is stored there,
 138      otherwise NULL is stored there.  */
 139   int (*find_and_open_solib) (const char *soname,
 140                               unsigned o_flags,
 141                               gdb::unique_xmalloc_ptr<char> *temp_pathname);
 142
 143   /* Given two so_list objects, one from the GDB thread list
 144      and another from the list returned by current_sos, return 1
 145      if they represent the same library.
 146      Falls back to using strcmp on so_original_name field when set
 147      to NULL.  */
 148   int (*same) (const shobj &gdb, const shobj &inferior);
 149
 150   /* Return whether a region of memory must be kept in a core file
 151      for shared libraries loaded before "gcore" is used to be
 152      handled correctly when the core file is loaded.  This only
 153      applies when the section would otherwise not be kept in the
 154      core file (in particular, for readonly sections).  */
 155   int (*keep_data_in_core) (CORE_ADDR vaddr,
 156                             unsigned long size);
 157
 158   /* Enable or disable optional solib event breakpoints as
 159      appropriate.  This should be called whenever
 160      stop_on_solib_events is changed.  This pointer can be
 161      NULL, in which case no enabling or disabling is necessary
 162      for this target.  */
 163   void (*update_breakpoints) (void);
 164
 165   /* Target-specific processing of solib events that will be
 166      performed before solib_add is called.  This pointer can be
 167      NULL, in which case no specific preprocessing is necessary
 168      for this target.  */
 169   void (*handle_event) (void);
 170 };
 171
 172 /* A unique pointer to a so_list.  */
 173 using shobj_up = std::unique_ptr<shobj>;
 174
 175 /* Find main executable binary file.  */
 176 extern gdb::unique_xmalloc_ptr<char> exec_file_find (const char *in_pathname,
 177                                                      int *fd);
 178
 179 /* Find shared library binary file.  */
 180 extern gdb::unique_xmalloc_ptr<char> solib_find (const char *in_pathname,
 181                                                  int *fd);
 182
 183 /* Open BFD for shared library file.  */
 184 extern gdb_bfd_ref_ptr solib_bfd_fopen (const char *pathname, int fd);
 185
 186 /* Find solib binary file and open it.  */
 187 extern gdb_bfd_ref_ptr solib_bfd_open (const char *in_pathname);
 188
 189 #endif