gdb/solib.c - gdb

Global variables defined

Functions defined

Macros defined

Source code

  1. /* Handle shared libraries for GDB, the GNU Debugger.

  3.    Copyright (C) 1990-2015 Free Software Foundation, Inc.

  5.    This file is part of GDB.

  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.

  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.

  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/>.  */

  20. #include "defs.h"

  22. #include <sys/types.h>
  23. #include <fcntl.h>
  24. #include "symtab.h"
  25. #include "bfd.h"
  26. #include "symfile.h"
  27. #include "objfiles.h"
  28. #include "gdbcore.h"
  29. #include "command.h"
  30. #include "target.h"
  31. #include "frame.h"
  32. #include "gdb_regex.h"
  33. #include "inferior.h"
  34. #include "environ.h"
  35. #include "language.h"
  36. #include "gdbcmd.h"
  37. #include "completer.h"
  38. #include "filenames.h"                /* for DOSish file names */
  39. #include "exec.h"
  40. #include "solist.h"
  41. #include "observer.h"
  42. #include "readline/readline.h"
  43. #include "remote.h"
  44. #include "solib.h"
  45. #include "interps.h"
  46. #include "filesystem.h"
  47. #include "gdb_bfd.h"
  48. #include "filestuff.h"

  50. /* Architecture-specific operations.  */

  52. /* Per-architecture data key.  */
  53. ‌static struct gdbarch_data *solib_data;

  55. static void *
  56. ‌solib_init (struct obstack *obstack)
  57. {
  58.   struct target_so_ops **ops;

  60.   ops = OBSTACK_ZALLOC (obstack, struct target_so_ops *);
  61.   *ops = current_target_so_ops;
  62.   return ops;
  63. }

  65. static const struct target_so_ops *
  66. ‌solib_ops (struct gdbarch *gdbarch)
  67. {
  68.   const struct target_so_ops **ops = gdbarch_data (gdbarch, solib_data);

  70.   return *ops;
  71. }

  73. /* Set the solib operations for GDBARCH to NEW_OPS.  */

  75. void
  76. ‌set_solib_ops (struct gdbarch *gdbarch, const struct target_so_ops *new_ops)
  77. {
  78.   const struct target_so_ops **ops = gdbarch_data (gdbarch, solib_data);

  80.   *ops = new_ops;
  81. }


  84. /* external data declarations */

  86. /* FIXME: gdbarch needs to control this variable, or else every
  87.    configuration needs to call set_solib_ops.  */
  88. ‌struct target_so_ops *current_target_so_ops;

  90. /* List of known shared objects */
  91. ‌#define so_list_head current_program_space->so_list

  93. /* Local function prototypes */

  95. /* If non-empty, this is a search path for loading non-absolute shared library
  96.    symbol files.  This takes precedence over the environment variables PATH
  97.    and LD_LIBRARY_PATH.  */
  98. ‌static char *solib_search_path = NULL;
  99. static void
  100. ‌show_solib_search_path (struct ui_file *file, int from_tty,
  101.                         struct cmd_list_element *c, const char *value)
  102. {
  103.   fprintf_filtered (file, _("The search path for loading non-absolute "
  104.                             "shared library symbol files is %s.\n"),
  105.                     value);
  106. }

  108. /* Same as HAVE_DOS_BASED_FILE_SYSTEM, but useable as an rvalue.  */
  109. #if (HAVE_DOS_BASED_FILE_SYSTEM)
  110. ‌#  define DOS_BASED_FILE_SYSTEM 1
  111. #else
  112. ‌#  define DOS_BASED_FILE_SYSTEM 0
  113. #endif

  115. /* Returns the full pathname of the shared library file, or NULL if
  116.    not found.  (The pathname is malloc'ed; it needs to be freed by the
  117.    caller.)  *FD is set to either -1 or an open file handle for the
  118.    library.

  120.    Global variable GDB_SYSROOT is used as a prefix directory
  121.    to search for shared libraries if they have an absolute path.

  123.    Global variable SOLIB_SEARCH_PATH is used as a prefix directory
  124.    (or set of directories, as in LD_LIBRARY_PATH) to search for all
  125.    shared libraries if not found in GDB_SYSROOT.

  127.    Search algorithm:
  128.    * If there is a gdb_sysroot and path is absolute:
  129.    *   Search for gdb_sysroot/path.
  130.    * else
  131.    *   Look for it literally (unmodified).
  132.    * Look in SOLIB_SEARCH_PATH.
  133.    * If available, use target defined search function.
  134.    * If gdb_sysroot is NOT set, perform the following two searches:
  135.    *   Look in inferior's $PATH.
  136.    *   Look in inferior's $LD_LIBRARY_PATH.
  137.    *
  138.    * The last check avoids doing this search when targetting remote
  139.    * machines since gdb_sysroot will almost always be set.
  140. */

  142. char *
  143. ‌solib_find (char *in_pathname, int *fd)
  144. {
  145.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());
  146.   int found_file = -1;
  147.   char *temp_pathname = NULL;
  148.   int gdb_sysroot_is_empty;
  149.   const char *solib_symbols_extension
  150.     = gdbarch_solib_symbols_extension (target_gdbarch ());
  151.   const char *fskind = effective_target_file_system_kind ();
  152.   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
  153.   char *sysroot = NULL;

  155.   /* If solib_symbols_extension is set, replace the file's
  156.      extension.  */
  157.   if (solib_symbols_extension)
  158.     {
  159.       char *p = in_pathname + strlen (in_pathname);

  161.       while (p > in_pathname && *p != '.')
  162.         p--;

  164.       if (*p == '.')
  165.         {
  166.           char *new_pathname;

  168.           new_pathname = alloca (p - in_pathname + 1
  169.                                  + strlen (solib_symbols_extension) + 1);
  170.           memcpy (new_pathname, in_pathname, p - in_pathname + 1);
  171.           strcpy (new_pathname + (p - in_pathname) + 1,
  172.                   solib_symbols_extension);

  174.           in_pathname = new_pathname;
  175.         }
  176.     }

  178.   gdb_sysroot_is_empty = (gdb_sysroot == NULL || *gdb_sysroot == 0);

  180.   if (!gdb_sysroot_is_empty)
  181.     {
  182.       int prefix_len = strlen (gdb_sysroot);

  184.       /* Remove trailing slashes from absolute prefix.  */
  185.       while (prefix_len > 0
  186.              && IS_DIR_SEPARATOR (gdb_sysroot[prefix_len - 1]))
  187.         prefix_len--;

  189.       sysroot = savestring (gdb_sysroot, prefix_len);
  190.       make_cleanup (xfree, sysroot);
  191.     }

  193.   /* If we're on a non-DOS-based system, backslashes won't be
  194.      understood as directory separator, so, convert them to forward
  195.      slashes, iff we're supposed to handle DOS-based file system
  196.      semantics for target paths.  */
  197.   if (!DOS_BASED_FILE_SYSTEM && fskind == file_system_kind_dos_based)
  198.     {
  199.       char *p;

  201.       /* Avoid clobbering our input.  */
  202.       p = alloca (strlen (in_pathname) + 1);
  203.       strcpy (p, in_pathname);
  204.       in_pathname = p;

  206.       for (; *p; p++)
  207.         {
  208.           if (*p == '\\')
  209.             *p = '/';
  210.         }
  211.     }

  213.   /* Note, we're interested in IS_TARGET_ABSOLUTE_PATH, not
  214.      IS_ABSOLUTE_PATH.  The latter is for host paths only, while
  215.      IN_PATHNAME is a target path.  For example, if we're supposed to
  216.      be handling DOS-like semantics we want to consider a
  217.      'c:/foo/bar.dll' path as an absolute path, even on a Unix box.
  218.      With such a path, before giving up on the sysroot, we'll try:

  220.        1st attempt, c:/foo/bar.dll ==> /sysroot/c:/foo/bar.dll
  221.        2nd attempt, c:/foo/bar.dll ==> /sysroot/c/foo/bar.dll
  222.        3rd attempt, c:/foo/bar.dll ==> /sysroot/foo/bar.dll
  223.   */

  225.   if (!IS_TARGET_ABSOLUTE_PATH (fskind, in_pathname) || gdb_sysroot_is_empty)
  226.     temp_pathname = xstrdup (in_pathname);
  227.   else
  228.     {
  229.       int need_dir_separator;

  231.       /* Concatenate the sysroot and the target reported filename.  We
  232.          may need to glue them with a directory separator.  Cases to
  233.          consider:

  235.         | sysroot         | separator | in_pathname    |
  236.         |-----------------+-----------+----------------|
  237.         | /some/dir       | /         | c:/foo/bar.dll |
  238.         | /some/dir       |           | /foo/bar.dll   |
  239.         | remote:         |           | c:/foo/bar.dll |
  240.         | remote:         |           | /foo/bar.dll   |
  241.         | remote:some/dir | /         | c:/foo/bar.dll |
  242.         | remote:some/dir |           | /foo/bar.dll   |

  244.         IOW, we don't need to add a separator if IN_PATHNAME already
  245.         has one, or when the the sysroot is exactly "remote:".
  246.         There's no need to check for drive spec explicitly, as we only
  247.         get here if IN_PATHNAME is considered an absolute path.  */
  248.       need_dir_separator = !(IS_DIR_SEPARATOR (in_pathname[0])
  249.                              || strcmp (REMOTE_SYSROOT_PREFIX, sysroot) == 0);

  251.       /* Cat the prefixed pathname together.  */
  252.       temp_pathname = concat (sysroot,
  253.                               need_dir_separator ? SLASH_STRING : "",
  254.                               in_pathname, (char *) NULL);
  255.     }

  257.   /* Handle remote files.  */
  258.   if (remote_filename_p (temp_pathname))
  259.     {
  260.       *fd = -1;
  261.       do_cleanups (old_chain);
  262.       return temp_pathname;
  263.     }

  265.   /* Now see if we can open it.  */
  266.   found_file = gdb_open_cloexec (temp_pathname, O_RDONLY | O_BINARY, 0);
  267.   if (found_file < 0)
  268.     xfree (temp_pathname);

  270.   /* If the search in gdb_sysroot failed, and the path name has a
  271.      drive spec (e.g, c:/foo), try stripping ':' from the drive spec,
  272.      and retrying in the sysroot:
  273.        c:/foo/bar.dll ==> /sysroot/c/foo/bar.dll.  */

  275.   if (found_file < 0
  276.       && !gdb_sysroot_is_empty
  277.       && HAS_TARGET_DRIVE_SPEC (fskind, in_pathname))
  278.     {
  279.       int need_dir_separator = !IS_DIR_SEPARATOR (in_pathname[2]);
  280.       char *drive = savestring (in_pathname, 1);

  282.       temp_pathname = concat (sysroot,
  283.                               SLASH_STRING,
  284.                               drive,
  285.                               need_dir_separator ? SLASH_STRING : "",
  286.                               in_pathname + 2, (char *) NULL);
  287.       xfree (drive);

  289.       found_file = gdb_open_cloexec (temp_pathname, O_RDONLY | O_BINARY, 0);
  290.       if (found_file < 0)
  291.         {
  292.           xfree (temp_pathname);

  294.           /* If the search in gdb_sysroot still failed, try fully
  295.              stripping the drive spec, and trying once more in the
  296.              sysroot before giving up.

  298.              c:/foo/bar.dll ==> /sysroot/foo/bar.dll.  */

  300.           temp_pathname = concat (sysroot,
  301.                                   need_dir_separator ? SLASH_STRING : "",
  302.                                   in_pathname + 2, (char *) NULL);

  304.           found_file = gdb_open_cloexec (temp_pathname, O_RDONLY | O_BINARY, 0);
  305.           if (found_file < 0)
  306.             xfree (temp_pathname);
  307.         }
  308.     }

  310.   do_cleanups (old_chain);

  312.   /* We try to find the library in various ways.  After each attempt,
  313.      either found_file >= 0 and temp_pathname is a malloc'd string, or
  314.      found_file < 0 and temp_pathname does not point to storage that
  315.      needs to be freed.  */

  317.   if (found_file < 0)
  318.     temp_pathname = NULL;

  320.   /* If the search in gdb_sysroot failed, and the path name is
  321.      absolute at this point, make it relative.  (openp will try and open the
  322.      file according to its absolute path otherwise, which is not what we want.)
  323.      Affects subsequent searches for this solib.  */
  324.   if (found_file < 0 && IS_TARGET_ABSOLUTE_PATH (fskind, in_pathname))
  325.     {
  326.       /* First, get rid of any drive letters etc.  */
  327.       while (!IS_TARGET_DIR_SEPARATOR (fskind, *in_pathname))
  328.         in_pathname++;

  330.       /* Next, get rid of all leading dir separators.  */
  331.       while (IS_TARGET_DIR_SEPARATOR (fskind, *in_pathname))
  332.         in_pathname++;
  333.     }

  335.   /* If not found, search the solib_search_path (if any).  */
  336.   if (found_file < 0 && solib_search_path != NULL)
  337.     found_file = openp (solib_search_path,
  338.                         OPF_TRY_CWD_FIRST | OPF_RETURN_REALPATH,
  339.                         in_pathname, O_RDONLY | O_BINARY, &temp_pathname);

  341.   /* If not found, next search the solib_search_path (if any) for the basename
  342.      only (ignoring the path).  This is to allow reading solibs from a path
  343.      that differs from the opened path.  */
  344.   if (found_file < 0 && solib_search_path != NULL)
  345.     found_file = openp (solib_search_path,
  346.                         OPF_TRY_CWD_FIRST | OPF_RETURN_REALPATH,
  347.                         target_lbasename (fskind, in_pathname),
  348.                         O_RDONLY | O_BINARY, &temp_pathname);

  350.   /* If not found, try to use target supplied solib search method.  */
  351.   if (found_file < 0 && ops->find_and_open_solib)
  352.     found_file = ops->find_and_open_solib (in_pathname, O_RDONLY | O_BINARY,
  353.                                            &temp_pathname);

  355.   /* If not found, next search the inferior's $PATH environment variable.  */
  356.   if (found_file < 0 && gdb_sysroot_is_empty)
  357.     found_file = openp (get_in_environ (current_inferior ()->environment,
  358.                                         "PATH"),
  359.                         OPF_TRY_CWD_FIRST | OPF_RETURN_REALPATH, in_pathname,
  360.                         O_RDONLY | O_BINARY, &temp_pathname);

  362.   /* If not found, next search the inferior's $LD_LIBRARY_PATH
  363.      environment variable.  */
  364.   if (found_file < 0 && gdb_sysroot_is_empty)
  365.     found_file = openp (get_in_environ (current_inferior ()->environment,
  366.                                         "LD_LIBRARY_PATH"),
  367.                         OPF_TRY_CWD_FIRST | OPF_RETURN_REALPATH, in_pathname,
  368.                         O_RDONLY | O_BINARY, &temp_pathname);

  370.   *fd = found_file;
  371.   return temp_pathname;
  372. }

  374. /* Open and return a BFD for the shared library PATHNAME.  If FD is not -1,
  375.    it is used as file handle to open the file.  Throws an error if the file
  376.    could not be opened.  Handles both local and remote file access.

  378.    PATHNAME must be malloc'ed by the caller.  It will be freed by this
  379.    function.  If unsuccessful, the FD will be closed (unless FD was
  380.    -1).  */

  382. bfd *
  383. ‌solib_bfd_fopen (char *pathname, int fd)
  384. {
  385.   bfd *abfd;

  387.   if (remote_filename_p (pathname))
  388.     {
  389.       gdb_assert (fd == -1);
  390.       abfd = remote_bfd_open (pathname, gnutarget);
  391.     }
  392.   else
  393.     {
  394.       abfd = gdb_bfd_open (pathname, gnutarget, fd);

  396.       if (abfd)
  397.         bfd_set_cacheable (abfd, 1);
  398.     }

  400.   if (!abfd)
  401.     {
  402.       make_cleanup (xfree, pathname);
  403.       error (_("Could not open `%s' as an executable file: %s"),
  404.              pathname, bfd_errmsg (bfd_get_error ()));
  405.     }

  407.   xfree (pathname);

  409.   return abfd;
  410. }

  412. /* Find shared library PATHNAME and open a BFD for it.  */

  414. bfd *
  415. ‌solib_bfd_open (char *pathname)
  416. {
  417.   char *found_pathname;
  418.   int found_file;
  419.   bfd *abfd;
  420.   const struct bfd_arch_info *b;

  422.   /* Search for shared library file.  */
  423.   found_pathname = solib_find (pathname, &found_file);
  424.   if (found_pathname == NULL)
  425.     {
  426.       /* Return failure if the file could not be found, so that we can
  427.          accumulate messages about missing libraries.  */
  428.       if (errno == ENOENT)
  429.         return NULL;

  431.       perror_with_name (pathname);
  432.     }

  434.   /* Open bfd for shared library.  */
  435.   abfd = solib_bfd_fopen (found_pathname, found_file);

  437.   /* Check bfd format.  */
  438.   if (!bfd_check_format (abfd, bfd_object))
  439.     {
  440.       make_cleanup_bfd_unref (abfd);
  441.       error (_("`%s': not in executable format: %s"),
  442.              bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
  443.     }

  445.   /* Check bfd arch.  */
  446.   b = gdbarch_bfd_arch_info (target_gdbarch ());
  447.   if (!b->compatible (b, bfd_get_arch_info (abfd)))
  448.     warning (_("`%s': Shared library architecture %s is not compatible "
  449.                "with target architecture %s."), bfd_get_filename (abfd),
  450.              bfd_get_arch_info (abfd)->printable_name, b->printable_name);

  452.   return abfd;
  453. }

  455. /* Given a pointer to one of the shared objects in our list of mapped
  456.    objects, use the recorded name to open a bfd descriptor for the
  457.    object, build a section table, relocate all the section addresses
  458.    by the base address at which the shared object was mapped, and then
  459.    add the sections to the target's section table.

  461.    FIXME: In most (all?) cases the shared object file name recorded in
  462.    the dynamic linkage tables will be a fully qualified pathname.  For
  463.    cases where it isn't, do we really mimic the systems search
  464.    mechanism correctly in the below code (particularly the tilde
  465.    expansion stuff?).  */

  467. static int
  468. ‌solib_map_sections (struct so_list *so)
  469. {
  470.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());
  471.   char *filename;
  472.   struct target_section *p;
  473.   struct cleanup *old_chain;
  474.   bfd *abfd;

  476.   filename = tilde_expand (so->so_name);
  477.   old_chain = make_cleanup (xfree, filename);
  478.   abfd = ops->bfd_open (filename);
  479.   do_cleanups (old_chain);

  481.   if (abfd == NULL)
  482.     return 0;

  484.   /* Leave bfd open, core_xfer_memory and "info files" need it.  */
  485.   so->abfd = abfd;

  487.   /* Copy the full path name into so_name, allowing symbol_file_add
  488.      to find it later.  This also affects the =library-loaded GDB/MI
  489.      event, and in particular the part of that notification providing
  490.      the library's host-side path.  If we let the target dictate
  491.      that objfile's path, and the target is different from the host,
  492.      GDB/MI will not provide the correct host-side path.  */
  493.   if (strlen (bfd_get_filename (abfd)) >= SO_NAME_MAX_PATH_SIZE)
  494.     error (_("Shared library file name is too long."));
  495.   strcpy (so->so_name, bfd_get_filename (abfd));

  497.   if (build_section_table (abfd, &so->sections, &so->sections_end))
  498.     {
  499.       error (_("Can't find the file sections in `%s': %s"),
  500.              bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
  501.     }

  503.   for (p = so->sections; p < so->sections_end; p++)
  504.     {
  505.       /* Relocate the section binding addresses as recorded in the shared
  506.          object's file by the base address to which the object was actually
  507.          mapped.  */
  508.       ops->relocate_section_addresses (so, p);

  510.       /* If the target didn't provide information about the address
  511.          range of the shared object, assume we want the location of
  512.          the .text section.  */
  513.       if (so->addr_low == 0 && so->addr_high == 0
  514.           && strcmp (p->the_bfd_section->name, ".text") == 0)
  515.         {
  516.           so->addr_low = p->addr;
  517.           so->addr_high = p->endaddr;
  518.         }
  519.     }

  521.   /* Add the shared object's sections to the current set of file
  522.      section tables.  Do this immediately after mapping the object so
  523.      that later nodes in the list can query this object, as is needed
  524.      in solib-osf.c.  */
  525.   add_target_sections (so, so->sections, so->sections_end);

  527.   return 1;
  528. }

  530. /* Free symbol-file related contents of SO and reset for possible reloading
  531.    of SO.  If we have opened a BFD for SO, close it.  If we have placed SO's
  532.    sections in some target's section table, the caller is responsible for
  533.    removing them.

  535.    This function doesn't mess with objfiles at all.  If there is an
  536.    objfile associated with SO that needs to be removed, the caller is
  537.    responsible for taking care of that.  */

  539. static void
  540. ‌clear_so (struct so_list *so)
  541. {
  542.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  544.   if (so->sections)
  545.     {
  546.       xfree (so->sections);
  547.       so->sections = so->sections_end = NULL;
  548.     }

  550.   gdb_bfd_unref (so->abfd);
  551.   so->abfd = NULL;

  553.   /* Our caller closed the objfile, possibly via objfile_purge_solibs.  */
  554.   so->symbols_loaded = 0;
  555.   so->objfile = NULL;

  557.   so->addr_low = so->addr_high = 0;

  559.   /* Restore the target-supplied file name.  SO_NAME may be the path
  560.      of the symbol file.  */
  561.   strcpy (so->so_name, so->so_original_name);

  563.   /* Do the same for target-specific data.  */
  564.   if (ops->clear_so != NULL)
  565.     ops->clear_so (so);
  566. }

  568. /* Free the storage associated with the `struct so_list' object SO.
  569.    If we have opened a BFD for SO, close it.

  571.    The caller is responsible for removing SO from whatever list it is
  572.    a member of.  If we have placed SO's sections in some target's
  573.    section table, the caller is responsible for removing them.

  575.    This function doesn't mess with objfiles at all.  If there is an
  576.    objfile associated with SO that needs to be removed, the caller is
  577.    responsible for taking care of that.  */

  579. void
  580. ‌free_so (struct so_list *so)
  581. {
  582.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  584.   clear_so (so);
  585.   ops->free_so (so);

  587.   xfree (so);
  588. }


  591. /* Return address of first so_list entry in master shared object list.  */
  592. struct so_list *
  593. ‌master_so_list (void)
  594. {
  595.   return so_list_head;
  596. }

  598. /* Read in symbols for shared object SO.  If SYMFILE_VERBOSE is set in FLAGS,
  599.    be chatty about it.  Return non-zero if any symbols were actually
  600.    loaded.  */

  602. int
  603. ‌solib_read_symbols (struct so_list *so, int flags)
  604. {
  605.   if (so->symbols_loaded)
  606.     {
  607.       /* If needed, we've already warned in our caller.  */
  608.     }
  609.   else if (so->abfd == NULL)
  610.     {
  611.       /* We've already warned about this library, when trying to open
  612.          it.  */
  613.     }
  614.   else
  615.     {
  616.       volatile struct gdb_exception e;

  618.       flags |= current_inferior ()->symfile_flags;

  620.       TRY_CATCH (e, RETURN_MASK_ERROR)
  621.         {
  622.           struct section_addr_info *sap;

  624.           /* Have we already loaded this shared object?  */
  625.           ALL_OBJFILES (so->objfile)
  626.             {
  627.               if (filename_cmp (objfile_name (so->objfile), so->so_name) == 0
  628.                   && so->objfile->addr_low == so->addr_low)
  629.                 break;
  630.             }
  631.           if (so->objfile != NULL)
  632.             break;

  634.           sap = build_section_addr_info_from_section_table (so->sections,
  635.                                                             so->sections_end);
  636.           so->objfile = symbol_file_add_from_bfd (so->abfd, so->so_name,
  637.                                                   flags, sap, OBJF_SHARED,
  638.                                                   NULL);
  639.           so->objfile->addr_low = so->addr_low;
  640.           free_section_addr_info (sap);
  641.         }

  643.       if (e.reason < 0)
  644.         exception_fprintf (gdb_stderr, e, _("Error while reading shared"
  645.                                             " library symbols for %s:\n"),
  646.                            so->so_name);
  647.       else
  648.         so->symbols_loaded = 1;
  649.       return 1;
  650.     }

  652.   return 0;
  653. }

  655. /* Return 1 if KNOWN->objfile is used by any other so_list object in the
  656.    SO_LIST_HEAD list.  Return 0 otherwise.  */

  658. static int
  659. ‌solib_used (const struct so_list *const known)
  660. {
  661.   const struct so_list *pivot;

  663.   for (pivot = so_list_head; pivot != NULL; pivot = pivot->next)
  664.     if (pivot != known && pivot->objfile == known->objfile)
  665.       return 1;
  666.   return 0;
  667. }

  669. /* Synchronize GDB's shared object list with inferior's.

  671.    Extract the list of currently loaded shared objects from the
  672.    inferior, and compare it with the list of shared objects currently
  673.    in GDB's so_list_head list.  Edit so_list_head to bring it in sync
  674.    with the inferior's new list.

  676.    If we notice that the inferior has unloaded some shared objects,
  677.    free any symbolic info GDB had read about those shared objects.

  679.    Don't load symbolic info for any new shared objects; just add them
  680.    to the list, and leave their symbols_loaded flag clear.

  682.    If FROM_TTY is non-null, feel free to print messages about what
  683.    we're doing.

  685.    If TARGET is non-null, add the sections of all new shared objects
  686.    to TARGET's section table.  Note that this doesn't remove any
  687.    sections for shared objects that have been unloaded, and it
  688.    doesn't check to see if the new shared objects are already present in
  689.    the section table.  But we only use this for core files and
  690.    processes we've just attached to, so that's okay.  */

  692. static void
  693. ‌update_solib_list (int from_tty, struct target_ops *target)
  694. {
  695.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());
  696.   struct so_list *inferior = ops->current_sos();
  697.   struct so_list *gdb, **gdb_link;

  699.   /* We can reach here due to changing solib-search-path or the
  700.      sysroot, before having any inferior.  */
  701.   if (target_has_execution && !ptid_equal (inferior_ptid, null_ptid))
  702.     {
  703.       struct inferior *inf = current_inferior ();

  705.       /* If we are attaching to a running process for which we
  706.          have not opened a symbol file, we may be able to get its
  707.          symbols now!  */
  708.       if (inf->attach_flag && symfile_objfile == NULL)
  709.         catch_errors (ops->open_symbol_file_object, &from_tty,
  710.                       "Error reading attached process's symbol file.\n",
  711.                       RETURN_MASK_ALL);
  712.     }

  714.   /* GDB and the inferior's dynamic linker each maintain their own
  715.      list of currently loaded shared objects; we want to bring the
  716.      former in sync with the latter.  Scan both lists, seeing which
  717.      shared objects appear where.  There are three cases:

  719.      - A shared object appears on both lists.  This means that GDB
  720.      knows about it already, and it's still loaded in the inferior.
  721.      Nothing needs to happen.

  723.      - A shared object appears only on GDB's list.  This means that
  724.      the inferior has unloaded it.  We should remove the shared
  725.      object from GDB's tables.

  727.      - A shared object appears only on the inferior's list.  This
  728.      means that it's just been loaded.  We should add it to GDB's
  729.      tables.

  731.      So we walk GDB's list, checking each entry to see if it appears
  732.      in the inferior's list too.  If it does, no action is needed, and
  733.      we remove it from the inferior's list.  If it doesn't, the
  734.      inferior has unloaded it, and we remove it from GDB's list.  By
  735.      the time we're done walking GDB's list, the inferior's list
  736.      contains only the new shared objects, which we then add.  */

  738.   gdb = so_list_head;
  739.   gdb_link = &so_list_head;
  740.   while (gdb)
  741.     {
  742.       struct so_list *i = inferior;
  743.       struct so_list **i_link = &inferior;

  745.       /* Check to see whether the shared object *gdb also appears in
  746.          the inferior's current list.  */
  747.       while (i)
  748.         {
  749.           if (ops->same)
  750.             {
  751.               if (ops->same (gdb, i))
  752.                 break;
  753.             }
  754.           else
  755.             {
  756.               if (! filename_cmp (gdb->so_original_name, i->so_original_name))
  757.                 break;
  758.             }

  760.           i_link = &i->next;
  761.           i = *i_link;
  762.         }

  764.       /* If the shared object appears on the inferior's list too, then
  765.          it's still loaded, so we don't need to do anything.  Delete
  766.          it from the inferior's list, and leave it on GDB's list.  */
  767.       if (i)
  768.         {
  769.           *i_link = i->next;
  770.           free_so (i);
  771.           gdb_link = &gdb->next;
  772.           gdb = *gdb_link;
  773.         }

  775.       /* If it's not on the inferior's list, remove it from GDB's tables.  */
  776.       else
  777.         {
  778.           /* Notify any observer that the shared object has been
  779.              unloaded before we remove it from GDB's tables.  */
  780.           observer_notify_solib_unloaded (gdb);

  782.           VEC_safe_push (char_ptr, current_program_space->deleted_solibs,
  783.                          xstrdup (gdb->so_name));

  785.           *gdb_link = gdb->next;

  787.           /* Unless the user loaded it explicitly, free SO's objfile.  */
  788.           if (gdb->objfile && ! (gdb->objfile->flags & OBJF_USERLOADED)
  789.               && !solib_used (gdb))
  790.             free_objfile (gdb->objfile);

  792.           /* Some targets' section tables might be referring to
  793.              sections from so->abfd; remove them.  */
  794.           remove_target_sections (gdb);

  796.           free_so (gdb);
  797.           gdb = *gdb_link;
  798.         }
  799.     }

  801.   /* Now the inferior's list contains only shared objects that don't
  802.      appear in GDB's list --- those that are newly loaded.  Add them
  803.      to GDB's shared object list.  */
  804.   if (inferior)
  805.     {
  806.       int not_found = 0;
  807.       const char *not_found_filename = NULL;

  809.       struct so_list *i;

  811.       /* Add the new shared objects to GDB's list.  */
  812.       *gdb_link = inferior;

  814.       /* Fill in the rest of each of the `struct so_list' nodes.  */
  815.       for (i = inferior; i; i = i->next)
  816.         {
  817.           volatile struct gdb_exception e;

  819.           i->pspace = current_program_space;
  820.           VEC_safe_push (so_list_ptr, current_program_space->added_solibs, i);

  822.           TRY_CATCH (e, RETURN_MASK_ERROR)
  823.             {
  824.               /* Fill in the rest of the `struct so_list' node.  */
  825.               if (!solib_map_sections (i))
  826.                 {
  827.                   not_found++;
  828.                   if (not_found_filename == NULL)
  829.                     not_found_filename = i->so_original_name;
  830.                 }
  831.             }

  833.           if (e.reason < 0)
  834.             exception_fprintf (gdb_stderr, e,
  835.                                _("Error while mapping shared "
  836.                                  "library sections:\n"));

  838.           /* Notify any observer that the shared object has been
  839.              loaded now that we've added it to GDB's tables.  */
  840.           observer_notify_solib_loaded (i);
  841.         }

  843.       /* If a library was not found, issue an appropriate warning
  844.          message.  We have to use a single call to warning in case the
  845.          front end does something special with warnings, e.g., pop up
  846.          a dialog box.  It Would Be Nice if we could get a "warning: "
  847.          prefix on each line in the CLI front end, though - it doesn't
  848.          stand out well.  */

  850.       if (not_found == 1)
  851.         warning (_("Could not load shared library symbols for %s.\n"
  852.                    "Do you need \"set solib-search-path\" "
  853.                    "or \"set sysroot\"?"),
  854.                  not_found_filename);
  855.       else if (not_found > 1)
  856.         warning (_("\
  857. Could not load shared library symbols for %d libraries, e.g. %s.\n\
  858. Use the \"info sharedlibrary\" command to see the complete listing.\n\
  859. Do you need \"set solib-search-path\" or \"set sysroot\"?"),
  860.                  not_found, not_found_filename);
  861.     }
  862. }


  865. /* Return non-zero if NAME is the libpthread shared library.

  867.    Uses a fairly simplistic heuristic approach where we check
  868.    the file name against "/libpthread".  This can lead to false
  869.    positives, but this should be good enough in practice.  */

  871. int
  872. ‌libpthread_name_p (const char *name)
  873. {
  874.   return (strstr (name, "/libpthread") != NULL);
  875. }

  877. /* Return non-zero if SO is the libpthread shared library.  */

  879. static int
  880. ‌libpthread_solib_p (struct so_list *so)
  881. {
  882.   return libpthread_name_p (so->so_name);
  883. }

  885. /* Read in symbolic information for any shared objects whose names
  886.    match PATTERN.  (If we've already read a shared object's symbol
  887.    info, leave it alone.)  If PATTERN is zero, read them all.

  889.    If READSYMS is 0, defer reading symbolic information until later
  890.    but still do any needed low level processing.

  892.    FROM_TTY and TARGET are as described for update_solib_list, above.  */

  894. void
  895. ‌solib_add (const char *pattern, int from_tty,
  896.            struct target_ops *target, int readsyms)
  897. {
  898.   struct so_list *gdb;

  900.   if (print_symbol_loading_p (from_tty, 0, 0))
  901.     {
  902.       if (pattern != NULL)
  903.         {
  904.           printf_unfiltered (_("Loading symbols for shared libraries: %s\n"),
  905.                              pattern);
  906.         }
  907.       else
  908.         printf_unfiltered (_("Loading symbols for shared libraries.\n"));
  909.     }

  911.   current_program_space->solib_add_generation++;

  913.   if (pattern)
  914.     {
  915.       char *re_err = re_comp (pattern);

  917.       if (re_err)
  918.         error (_("Invalid regexp: %s"), re_err);
  919.     }

  921.   update_solib_list (from_tty, target);

  923.   /* Walk the list of currently loaded shared libraries, and read
  924.      symbols for any that match the pattern --- or any whose symbols
  925.      aren't already loaded, if no pattern was given.  */
  926.   {
  927.     int any_matches = 0;
  928.     int loaded_any_symbols = 0;
  929.     const int flags =
  930.         SYMFILE_DEFER_BP_RESET | (from_tty ? SYMFILE_VERBOSE : 0);

  932.     for (gdb = so_list_head; gdb; gdb = gdb->next)
  933.       if (! pattern || re_exec (gdb->so_name))
  934.         {
  935.           /* Normally, we would read the symbols from that library
  936.              only if READSYMS is set.  However, we're making a small
  937.              exception for the pthread library, because we sometimes
  938.              need the library symbols to be loaded in order to provide
  939.              thread support (x86-linux for instance).  */
  940.           const int add_this_solib =
  941.             (readsyms || libpthread_solib_p (gdb));

  943.           any_matches = 1;
  944.           if (add_this_solib)
  945.             {
  946.               if (gdb->symbols_loaded)
  947.                 {
  948.                   /* If no pattern was given, be quiet for shared
  949.                      libraries we have already loaded.  */
  950.                   if (pattern && (from_tty || info_verbose))
  951.                     printf_unfiltered (_("Symbols already loaded for %s\n"),
  952.                                        gdb->so_name);
  953.                 }
  954.               else if (solib_read_symbols (gdb, flags))
  955.                 loaded_any_symbols = 1;
  956.             }
  957.         }

  959.     if (loaded_any_symbols)
  960.       breakpoint_re_set ();

  962.     if (from_tty && pattern && ! any_matches)
  963.       printf_unfiltered
  964.         ("No loaded shared libraries match the pattern `%s'.\n", pattern);

  966.     if (loaded_any_symbols)
  967.       {
  968.         const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  970.         /* Getting new symbols may change our opinion about what is
  971.            frameless.  */
  972.         reinit_frame_cache ();

  974.         ops->special_symbol_handling ();
  975.       }
  976.   }
  977. }

  979. /* Implement the "info sharedlibrary" command.  Walk through the
  980.    shared library list and print information about each attached
  981.    library matching PATTERN.  If PATTERN is elided, print them
  982.    all.  */

  984. static void
  985. ‌info_sharedlibrary_command (char *pattern, int from_tty)
  986. {
  987.   struct so_list *so = NULL;        /* link map state variable */
  988.   int so_missing_debug_info = 0;
  989.   int addr_width;
  990.   int nr_libs;
  991.   struct cleanup *table_cleanup;
  992.   struct gdbarch *gdbarch = target_gdbarch ();
  993.   struct ui_out *uiout = current_uiout;

  995.   if (pattern)
  996.     {
  997.       char *re_err = re_comp (pattern);

  999.       if (re_err)
  1000.         error (_("Invalid regexp: %s"), re_err);
  1001.     }

  1003.   /* "0x", a little whitespace, and two hex digits per byte of pointers.  */
  1004.   addr_width = 4 + (gdbarch_ptr_bit (gdbarch) / 4);

  1006.   update_solib_list (from_tty, 0);

  1008.   /* make_cleanup_ui_out_table_begin_end needs to know the number of
  1009.      rows, so we need to make two passes over the libs.  */

  1011.   for (nr_libs = 0, so = so_list_head; so; so = so->next)
  1012.     {
  1013.       if (so->so_name[0])
  1014.         {
  1015.           if (pattern && ! re_exec (so->so_name))
  1016.             continue;
  1017.           ++nr_libs;
  1018.         }
  1019.     }

  1021.   table_cleanup =
  1022.     make_cleanup_ui_out_table_begin_end (uiout, 4, nr_libs,
  1023.                                          "SharedLibraryTable");

  1025.   /* The "- 1" is because ui_out adds one space between columns.  */
  1026.   ui_out_table_header (uiout, addr_width - 1, ui_left, "from", "From");
  1027.   ui_out_table_header (uiout, addr_width - 1, ui_left, "to", "To");
  1028.   ui_out_table_header (uiout, 12 - 1, ui_left, "syms-read", "Syms Read");
  1029.   ui_out_table_header (uiout, 0, ui_noalign,
  1030.                        "name", "Shared Object Library");

  1032.   ui_out_table_body (uiout);

  1034.   for (so = so_list_head; so; so = so->next)
  1035.     {
  1036.       struct cleanup *lib_cleanup;

  1038.       if (! so->so_name[0])
  1039.         continue;
  1040.       if (pattern && ! re_exec (so->so_name))
  1041.         continue;

  1043.       lib_cleanup = make_cleanup_ui_out_tuple_begin_end (uiout, "lib");

  1045.       if (so->addr_high != 0)
  1046.         {
  1047.           ui_out_field_core_addr (uiout, "from", gdbarch, so->addr_low);
  1048.           ui_out_field_core_addr (uiout, "to", gdbarch, so->addr_high);
  1049.         }
  1050.       else
  1051.         {
  1052.           ui_out_field_skip (uiout, "from");
  1053.           ui_out_field_skip (uiout, "to");
  1054.         }

  1056.       if (! ui_out_is_mi_like_p (interp_ui_out (top_level_interpreter ()))
  1057.           && so->symbols_loaded
  1058.           && !objfile_has_symbols (so->objfile))
  1059.         {
  1060.           so_missing_debug_info = 1;
  1061.           ui_out_field_string (uiout, "syms-read", "Yes (*)");
  1062.         }
  1063.       else
  1064.         ui_out_field_string (uiout, "syms-read",
  1065.                              so->symbols_loaded ? "Yes" : "No");

  1067.       ui_out_field_string (uiout, "name", so->so_name);

  1069.       ui_out_text (uiout, "\n");

  1071.       do_cleanups (lib_cleanup);
  1072.     }

  1074.   do_cleanups (table_cleanup);

  1076.   if (nr_libs == 0)
  1077.     {
  1078.       if (pattern)
  1079.         ui_out_message (uiout, 0,
  1080.                         _("No shared libraries matched.\n"));
  1081.       else
  1082.         ui_out_message (uiout, 0,
  1083.                         _("No shared libraries loaded at this time.\n"));
  1084.     }
  1085.   else
  1086.     {
  1087.       if (so_missing_debug_info)
  1088.         ui_out_message (uiout, 0,
  1089.                         _("(*): Shared library is missing "
  1090.                           "debugging information.\n"));
  1091.     }
  1092. }

  1094. /* Return 1 if ADDRESS lies within SOLIB.  */

  1096. int
  1097. ‌solib_contains_address_p (const struct so_list *const solib,
  1098.                           CORE_ADDR address)
  1099. {
  1100.   struct target_section *p;

  1102.   for (p = solib->sections; p < solib->sections_end; p++)
  1103.     if (p->addr <= address && address < p->endaddr)
  1104.       return 1;

  1106.   return 0;
  1107. }

  1109. /* If ADDRESS is in a shared lib in program space PSPACE, return its
  1110.    name.

  1112.    Provides a hook for other gdb routines to discover whether or not a
  1113.    particular address is within the mapped address space of a shared
  1114.    library.

  1116.    For example, this routine is called at one point to disable
  1117.    breakpoints which are in shared libraries that are not currently
  1118.    mapped in.  */

  1120. char *
  1121. ‌solib_name_from_address (struct program_space *pspace, CORE_ADDR address)
  1122. {
  1123.   struct so_list *so = NULL;

  1125.   for (so = pspace->so_list; so; so = so->next)
  1126.     if (solib_contains_address_p (so, address))
  1127.       return (so->so_name);

  1129.   return (0);
  1130. }

  1132. /* Return whether the data starting at VADDR, size SIZE, must be kept
  1133.    in a core file for shared libraries loaded before "gcore" is used
  1134.    to be handled correctly when the core file is loaded.  This only
  1135.    applies when the section would otherwise not be kept in the core
  1136.    file (in particular, for readonly sections).  */

  1138. int
  1139. ‌solib_keep_data_in_core (CORE_ADDR vaddr, unsigned long size)
  1140. {
  1141.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1143.   if (ops->keep_data_in_core)
  1144.     return ops->keep_data_in_core (vaddr, size);
  1145.   else
  1146.     return 0;
  1147. }

  1149. /* Called by free_all_symtabs */

  1151. void
  1152. ‌clear_solib (void)
  1153. {
  1154.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1156.   /* This function is expected to handle ELF shared libraries.  It is
  1157.      also used on Solaris, which can run either ELF or a.out binaries
  1158.      (for compatibility with SunOS 4), both of which can use shared
  1159.      libraries.  So we don't know whether we have an ELF executable or
  1160.      an a.out executable until the user chooses an executable file.

  1162.      ELF shared libraries don't get mapped into the address space
  1163.      until after the program starts, so we'd better not try to insert
  1164.      breakpoints in them immediately.  We have to wait until the
  1165.      dynamic linker has loaded them; we'll hit a bp_shlib_event
  1166.      breakpoint (look for calls to create_solib_event_breakpoint) when
  1167.      it's ready.

  1169.      SunOS shared libraries seem to be different --- they're present
  1170.      as soon as the process begins execution, so there's no need to
  1171.      put off inserting breakpoints.  There's also nowhere to put a
  1172.      bp_shlib_event breakpoint, so if we put it off, we'll never get
  1173.      around to it.

  1175.      So: disable breakpoints only if we're using ELF shared libs.  */
  1176.   if (exec_bfd != NULL
  1177.       && bfd_get_flavour (exec_bfd) != bfd_target_aout_flavour)
  1178.     disable_breakpoints_in_shlibs ();

  1180.   while (so_list_head)
  1181.     {
  1182.       struct so_list *so = so_list_head;

  1184.       so_list_head = so->next;
  1185.       observer_notify_solib_unloaded (so);
  1186.       remove_target_sections (so);
  1187.       free_so (so);
  1188.     }

  1190.   ops->clear_solib ();
  1191. }

  1193. /* Shared library startup support.  When GDB starts up the inferior,
  1194.    it nurses it along (through the shell) until it is ready to execute
  1195.    its first instruction.  At this point, this function gets
  1196.    called.  */

  1198. void
  1199. ‌solib_create_inferior_hook (int from_tty)
  1200. {
  1201.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1203.   ops->solib_create_inferior_hook (from_tty);
  1204. }

  1206. /* Check to see if an address is in the dynamic loader's dynamic
  1207.    symbol resolution code.  Return 1 if so, 0 otherwise.  */

  1209. int
  1210. ‌in_solib_dynsym_resolve_code (CORE_ADDR pc)
  1211. {
  1212.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1214.   return ops->in_dynsym_resolve_code (pc);
  1215. }

  1217. /* Implements the "sharedlibrary" command.  */

  1219. static void
  1220. ‌sharedlibrary_command (char *args, int from_tty)
  1221. {
  1222.   dont_repeat ();
  1223.   solib_add (args, from_tty, (struct target_ops *) 0, 1);
  1224. }

  1226. /* Implements the command "nosharedlibrary", which discards symbols
  1227.    that have been auto-loaded from shared libraries.  Symbols from
  1228.    shared libraries that were added by explicit request of the user
  1229.    are not discarded.  Also called from remote.c.  */

  1231. void
  1232. ‌no_shared_libraries (char *ignored, int from_tty)
  1233. {
  1234.   /* The order of the two routines below is important: clear_solib notifies
  1235.      the solib_unloaded observers, and some of these observers might need
  1236.      access to their associated objfiles.  Therefore, we can not purge the
  1237.      solibs' objfiles before clear_solib has been called.  */

  1239.   clear_solib ();
  1240.   objfile_purge_solibs ();
  1241. }

  1243. /* See solib.h.  */

  1245. void
  1246. ‌update_solib_breakpoints (void)
  1247. {
  1248.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1250.   if (ops->update_breakpoints != NULL)
  1251.     ops->update_breakpoints ();
  1252. }

  1254. /* See solib.h.  */

  1256. void
  1257. ‌handle_solib_event (void)
  1258. {
  1259.   const struct target_so_ops *ops = solib_ops (target_gdbarch ());

  1261.   if (ops->handle_event != NULL)
  1262.     ops->handle_event ();

  1264.   clear_program_space_solib_cache (current_inferior ()->pspace);

  1266.   /* Check for any newly added shared libraries if we're supposed to
  1267.      be adding them automatically.  Switch terminal for any messages
  1268.      produced by breakpoint_re_set.  */
  1269.   target_terminal_ours_for_output ();
  1270.   solib_add (NULL, 0, &current_target, auto_solib_add);
  1271.   target_terminal_inferior ();
  1272. }

  1274. /* Reload shared libraries, but avoid reloading the same symbol file
  1275.    we already have loaded.  */

  1277. static void
  1278. ‌reload_shared_libraries_1 (int from_tty)
  1279. {
  1280.   struct so_list *so;
  1281.   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);

  1283.   if (print_symbol_loading_p (from_tty, 0, 0))
  1284.     printf_unfiltered (_("Loading symbols for shared libraries.\n"));

  1286.   for (so = so_list_head; so != NULL; so = so->next)
  1287.     {
  1288.       char *filename, *found_pathname = NULL;
  1289.       bfd *abfd;
  1290.       int was_loaded = so->symbols_loaded;
  1291.       const int flags =
  1292.         SYMFILE_DEFER_BP_RESET | (from_tty ? SYMFILE_VERBOSE : 0);

  1294.       filename = tilde_expand (so->so_original_name);
  1295.       make_cleanup (xfree, filename);
  1296.       abfd = solib_bfd_open (filename);
  1297.       if (abfd != NULL)
  1298.         {
  1299.           found_pathname = xstrdup (bfd_get_filename (abfd));
  1300.           make_cleanup (xfree, found_pathname);
  1301.           gdb_bfd_unref (abfd);
  1302.         }

  1304.       /* If this shared library is no longer associated with its previous
  1305.          symbol file, close that.  */
  1306.       if ((found_pathname == NULL && was_loaded)
  1307.           || (found_pathname != NULL
  1308.               && filename_cmp (found_pathname, so->so_name) != 0))
  1309.         {
  1310.           if (so->objfile && ! (so->objfile->flags & OBJF_USERLOADED)
  1311.               && !solib_used (so))
  1312.             free_objfile (so->objfile);
  1313.           remove_target_sections (so);
  1314.           clear_so (so);
  1315.         }

  1317.       /* If this shared library is now associated with a new symbol
  1318.          file, open it.  */
  1319.       if (found_pathname != NULL
  1320.           && (!was_loaded
  1321.               || filename_cmp (found_pathname, so->so_name) != 0))
  1322.         {
  1323.           volatile struct gdb_exception e;

  1325.           TRY_CATCH (e, RETURN_MASK_ERROR)
  1326.             solib_map_sections (so);

  1328.           if (e.reason < 0)
  1329.             exception_fprintf (gdb_stderr, e,
  1330.                                _("Error while mapping "
  1331.                                  "shared library sections:\n"));
  1332.           else if (auto_solib_add || was_loaded || libpthread_solib_p (so))
  1333.             solib_read_symbols (so, flags);
  1334.         }
  1335.     }

  1337.   do_cleanups (old_chain);
  1338. }

  1340. static void
  1341. ‌reload_shared_libraries (char *ignored, int from_tty,
  1342.                          struct cmd_list_element *e)
  1343. {
  1344.   const struct target_so_ops *ops;

  1346.   reload_shared_libraries_1 (from_tty);

  1348.   ops = solib_ops (target_gdbarch ());

  1350.   /* Creating inferior hooks here has two purposes.  First, if we reload
  1351.      shared libraries then the address of solib breakpoint we've computed
  1352.      previously might be no longer valid.  For example, if we forgot to set
  1353.      solib-absolute-prefix and are setting it right now, then the previous
  1354.      breakpoint address is plain wrong.  Second, installing solib hooks
  1355.      also implicitly figures were ld.so is and loads symbols for it.
  1356.      Absent this call, if we've just connected to a target and set
  1357.      solib-absolute-prefix or solib-search-path, we'll lose all information
  1358.      about ld.so.  */
  1359.   if (target_has_execution)
  1360.     {
  1361.       /* Reset or free private data structures not associated with
  1362.          so_list entries.  */
  1363.       ops->clear_solib ();

  1365.       /* Remove any previous solib event breakpoint.  This is usually
  1366.          done in common code, at breakpoint_init_inferior time, but
  1367.          we're not really starting up the inferior here.  */
  1368.       remove_solib_event_breakpoints ();

  1370.       solib_create_inferior_hook (from_tty);
  1371.     }

  1373.   /* Sometimes the platform-specific hook loads initial shared
  1374.      libraries, and sometimes it doesn't.  If it doesn't FROM_TTY will be
  1375.      incorrectly 0 but such solib targets should be fixed anyway.  If we
  1376.      made all the inferior hook methods consistent, this call could be
  1377.      removed.  Call it only after the solib target has been initialized by
  1378.      solib_create_inferior_hook.  */

  1380.   solib_add (NULL, 0, NULL, auto_solib_add);

  1382.   breakpoint_re_set ();

  1384.   /* We may have loaded or unloaded debug info for some (or all)
  1385.      shared libraries.  However, frames may still reference them.  For
  1386.      example, a frame's unwinder might still point at DWARF FDE
  1387.      structures that are now freed.  Also, getting new symbols may
  1388.      change our opinion about what is frameless.  */
  1389.   reinit_frame_cache ();

  1391.   ops->special_symbol_handling ();
  1392. }

  1394. static void
  1395. ‌show_auto_solib_add (struct ui_file *file, int from_tty,
  1396.                      struct cmd_list_element *c, const char *value)
  1397. {
  1398.   fprintf_filtered (file, _("Autoloading of shared library symbols is %s.\n"),
  1399.                     value);
  1400. }


  1403. /* Handler for library-specific lookup of global symbol NAME in OBJFILE.  Call
  1404.    the library-specific handler if it is installed for the current target.  */

  1406. struct symbol *
  1407. ‌solib_global_lookup (struct objfile *objfile,
  1408.                      const char *name,
  1409.                      const domain_enum domain)
  1410. {
  1411.   const struct target_so_ops *ops = solib_ops (get_objfile_arch (objfile));

  1413.   if (ops->lookup_lib_global_symbol != NULL)
  1414.     return ops->lookup_lib_global_symbol (objfile, name, domain);
  1415.   return NULL;
  1416. }

  1418. /* Lookup the value for a specific symbol from dynamic symbol table.  Look
  1419.    up symbol from ABFD.  MATCH_SYM is a callback function to determine
  1420.    whether to pick up a symbol.  DATA is the input of this callback
  1421.    function.  Return NULL if symbol is not found.  */

  1423. CORE_ADDR
  1424. ‌gdb_bfd_lookup_symbol_from_symtab (bfd *abfd,
  1425.                                    int (*match_sym) (asymbol *, void *),
  1426.                                    void *data)
  1427. {
  1428.   long storage_needed = bfd_get_symtab_upper_bound (abfd);
  1429.   CORE_ADDR symaddr = 0;

  1431.   if (storage_needed > 0)
  1432.     {
  1433.       unsigned int i;

  1435.       asymbol **symbol_table = (asymbol **) xmalloc (storage_needed);
  1436.       struct cleanup *back_to = make_cleanup (xfree, symbol_table);
  1437.       unsigned int number_of_symbols =
  1438.         bfd_canonicalize_symtab (abfd, symbol_table);

  1440.       for (i = 0; i < number_of_symbols; i++)
  1441.         {
  1442.           asymbol *sym  = *symbol_table++;

  1444.           if (match_sym (sym, data))
  1445.             {
  1446.               struct gdbarch *gdbarch = target_gdbarch ();
  1447.               symaddr = sym->value;

  1449.               /* Some ELF targets fiddle with addresses of symbols they
  1450.                  consider special.  They use minimal symbols to do that
  1451.                  and this is needed for correct breakpoint placement,
  1452.                  but we do not have full data here to build a complete
  1453.                  minimal symbol, so just set the address and let the
  1454.                  targets cope with that.  */
  1455.               if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
  1456.                   && gdbarch_elf_make_msymbol_special_p (gdbarch))
  1457.                 {
  1458.                   struct minimal_symbol msym;

  1460.                   memset (&msym, 0, sizeof (msym));
  1461.                   SET_MSYMBOL_VALUE_ADDRESS (&msym, symaddr);
  1462.                   gdbarch_elf_make_msymbol_special (gdbarch, sym, &msym);
  1463.                   symaddr = MSYMBOL_VALUE_RAW_ADDRESS (&msym);
  1464.                 }

  1466.               /* BFD symbols are section relative.  */
  1467.               symaddr += sym->section->vma;
  1468.               break;
  1469.             }
  1470.         }
  1471.       do_cleanups (back_to);
  1472.     }

  1474.   return symaddr;
  1475. }

  1477. /* Lookup the value for a specific symbol from symbol table.  Look up symbol
  1478.    from ABFD.  MATCH_SYM is a callback function to determine whether to pick
  1479.    up a symbol.  DATA is the input of this callback function.  Return NULL
  1480.    if symbol is not found.  */

  1482. static CORE_ADDR
  1483. ‌bfd_lookup_symbol_from_dyn_symtab (bfd *abfd,
  1484.                                    int (*match_sym) (asymbol *, void *),
  1485.                                    void *data)
  1486. {
  1487.   long storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd);
  1488.   CORE_ADDR symaddr = 0;

  1490.   if (storage_needed > 0)
  1491.     {
  1492.       unsigned int i;
  1493.       asymbol **symbol_table = (asymbol **) xmalloc (storage_needed);
  1494.       struct cleanup *back_to = make_cleanup (xfree, symbol_table);
  1495.       unsigned int number_of_symbols =
  1496.         bfd_canonicalize_dynamic_symtab (abfd, symbol_table);

  1498.       for (i = 0; i < number_of_symbols; i++)
  1499.         {
  1500.           asymbol *sym = *symbol_table++;

  1502.           if (match_sym (sym, data))
  1503.             {
  1504.               /* BFD symbols are section relative.  */
  1505.               symaddr = sym->value + sym->section->vma;
  1506.               break;
  1507.             }
  1508.         }
  1509.       do_cleanups (back_to);
  1510.     }
  1511.   return symaddr;
  1512. }

  1514. /* Lookup the value for a specific symbol from symbol table and dynamic
  1515.    symbol table.  Look up symbol from ABFD.  MATCH_SYM is a callback
  1516.    function to determine whether to pick up a symbol.  DATA is the
  1517.    input of this callback function.  Return NULL if symbol is not
  1518.    found.  */

  1520. CORE_ADDR
  1521. ‌gdb_bfd_lookup_symbol (bfd *abfd,
  1522.                        int (*match_sym) (asymbol *, void *),
  1523.                        void *data)
  1524. {
  1525.   CORE_ADDR symaddr = gdb_bfd_lookup_symbol_from_symtab (abfd, match_sym, data);

  1527.   /* On FreeBSD, the dynamic linker is stripped by default.  So we'll
  1528.      have to check the dynamic string table too.  */
  1529.   if (symaddr == 0)
  1530.     symaddr = bfd_lookup_symbol_from_dyn_symtab (abfd, match_sym, data);

  1532.   return symaddr;
  1533. }

  1535. /* SO_LIST_HEAD may contain user-loaded object files that can be removed
  1536.    out-of-band by the user.  So upon notification of free_objfile remove
  1537.    all references to any user-loaded file that is about to be freed.  */

  1539. static void
  1540. ‌remove_user_added_objfile (struct objfile *objfile)
  1541. {
  1542.   struct so_list *so;

  1544.   if (objfile != 0 && objfile->flags & OBJF_USERLOADED)
  1545.     {
  1546.       for (so = so_list_head; so != NULL; so = so->next)
  1547.         if (so->objfile == objfile)
  1548.           so->objfile = NULL;
  1549.     }
  1550. }

  1552. extern initialize_file_ftype _initialize_solib; /* -Wmissing-prototypes */

  1554. void
  1555. ‌_initialize_solib (void)
  1556. {
  1557.   solib_data = gdbarch_data_register_pre_init (solib_init);

  1559.   observer_attach_free_objfile (remove_user_added_objfile);

  1561.   add_com ("sharedlibrary", class_files, sharedlibrary_command,
  1562.            _("Load shared object library symbols for files matching REGEXP."));
  1563.   add_info ("sharedlibrary", info_sharedlibrary_command,
  1564.             _("Status of loaded shared object libraries."));
  1565.   add_com ("nosharedlibrary", class_files, no_shared_libraries,
  1566.            _("Unload all shared object library symbols."));

  1568.   add_setshow_boolean_cmd ("auto-solib-add", class_support,
  1569.                            &auto_solib_add, _("\
  1570. Set autoloading of shared library symbols."), _("\
  1571. Show autoloading of shared library symbols."), _("\
  1572. If \"on\", symbols from all shared object libraries will be loaded\n\
  1573. automatically when the inferior begins execution, when the dynamic linker\n\
  1574. informs gdb that a new library has been loaded, or when attaching to the\n\
  1575. inferior.  Otherwise, symbols must be loaded manually, using \
  1576. `sharedlibrary'."),
  1577.                            NULL,
  1578.                            show_auto_solib_add,
  1579.                            &setlist, &showlist);

  1581.   add_setshow_filename_cmd ("sysroot", class_support,
  1582.                             &gdb_sysroot, _("\
  1583. Set an alternate system root."), _("\
  1584. Show the current system root."), _("\
  1585. The system root is used to load absolute shared library symbol files.\n\
  1586. For other (relative) files, you can add directories using\n\
  1587. `set solib-search-path'."),
  1588.                             reload_shared_libraries,
  1589.                             NULL,
  1590.                             &setlist, &showlist);

  1592.   add_alias_cmd ("solib-absolute-prefix", "sysroot", class_support, 0,
  1593.                  &setlist);
  1594.   add_alias_cmd ("solib-absolute-prefix", "sysroot", class_support, 0,
  1595.                  &showlist);

  1597.   add_setshow_optional_filename_cmd ("solib-search-path", class_support,
  1598.                                      &solib_search_path, _("\
  1599. Set the search path for loading non-absolute shared library symbol files."),
  1600.                                      _("\
  1601. Show the search path for loading non-absolute shared library symbol files."),
  1602.                                      _("\
  1603. This takes precedence over the environment variables \
  1604. PATH and LD_LIBRARY_PATH."),
  1605.                                      reload_shared_libraries,
  1606.                                      show_solib_search_path,
  1607.                                      &setlist, &showlist);
  1608. }