gdb: Add new commands to list module variables and functions

This patch adds two new commands "info module functions" and "info
module variables".  These commands list all of the functions and
variables grouped by module and then by file.

For example:

  (gdb) info module functions
  All functions in all modules:

  Module "mod1":

  File /some/path/gdb/testsuite/gdb.fortran/info-types.f90:
  35:	void mod1::__copy_mod1_M1t1(Type m1t1, Type m1t1);
  25:	void mod1::sub_m1_a(integer(kind=4));
  31:	integer(kind=4) mod1::sub_m1_b(void);

  Module "mod2":

  File /some/path/gdb/testsuite/gdb.fortran/info-types.f90:
  41:	void mod2::sub_m2_a(integer(kind=4), logical(kind=4));
  49:	logical(kind=4) mod2::sub_m2_b(real(kind=4));

The new commands take set of flags that allow the output to be
filtered, the user can filter by variable/function name, type, or
containing module.

As GDB doesn't currently track the relationship between a module and
the variables or functions within it in the symbol table, so I filter
based on the module prefix in order to find the functions or variables
in each module.  What this makes clear is that a user could get this
same information using "info variables" and simply provide the prefix
themselves, for example:

  (gdb) info module functions -m mod1 _a
  All functions matching regular expression "_a",
  	in all modules matching regular expression "mod1":

  Module "mod1":

  File /some/path/gdb/testsuite/gdb.fortran/info-types.f90:
  25:	void mod1::sub_m1_a(integer(kind=4));

Is similar to:

  (gdb) info functions mod1::.*_a.*
  All functions matching regular expression "mod1::.*_a":

  File /some/path/gdb/testsuite/gdb.fortran/info-types.f90:
  25:	void mod1::sub_m1_a(integer(kind=4));

The benefits I see for a separate command are that the user doesn't
have to think (or know) about the module prefix format, nor worry
about building a proper regexp.  The user can also easily scan across
modules without having to build complex regexps.

The new function search_module_symbols is extern in this patch despite
only being used within symtab.c, this is because a later patch in this
series will also be using this function from outside symtab.c.

This patch is a new implementation of an idea originally worked on by
Mark O'Connor, Chris January, David Lecomber, and Xavier Oro from ARM.

gdb/ChangeLog:

	* symtab.c (info_module_cmdlist): New variable.
	(info_module_command): New function.
	(search_module_symbols): New function.
	(info_module_subcommand): New function.
	(struct info_modules_var_func_options): New struct.
	(info_modules_var_func_options_defs): New variable.
	(make_info_modules_var_func_options_def_group): New function.
	(info_module_functions_command): New function.
	(info_module_variables_command): New function.
	(info_module_var_func_command_completer): New function.
	(_initialize_symtab): Register new 'info module functions' and
	'info module variables' commands.
	* symtab.h (typedef symbol_search_in_module): New typedef.
	(search_module_symbols): Declare new function.
	* NEWS: Mention new commands.

gdb/doc/ChangeLog:

	* gdb.texinfo (Symbols): Document new 'info module variables' and
	'info module functions' commands.

gdb/testsuite/ChangeLog:

	* gdb.fortran/info-modules.exp: Update expected results, and add
	additional tests for 'info module functinos', and 'info module
	variables'.
	* gdb.fortran/info-types.exp: Update expected results.
	* gdb.fortran/info-types.f90: Extend testcase with additional
	module variables and functions.

Change-Id: I8c2960640e2e101b77eff54027d687e21ec22e2b

1 files changed, 348 insertions, 0 deletions

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 4c14eda..72a54ec 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -6340,6 +6340,315 @@ get_msymbol_address (struct objfile *objf, const struct minimal_symbol *minsym)
 
 
 
+/* Hold the sub-commands of 'info module'.  */
+
+static struct cmd_list_element *info_module_cmdlist = NULL;
+
+/* Implement the 'info module' command, just displays some help text for
+   the available sub-commands.  */
+
+static void
+info_module_command (const char *args, int from_tty)
+{
+  help_list (info_module_cmdlist, "info module ", class_info, gdb_stdout);
+}
+
+/* See symtab.h.  */
+
+std::vector<module_symbol_search>
+search_module_symbols (const char *module_regexp, const char *regexp,
+		       const char *type_regexp, search_domain kind)
+{
+  std::vector<module_symbol_search> results;
+
+  /* Search for all modules matching MODULE_REGEXP.  */
+  std::vector<symbol_search> modules = search_symbols (module_regexp,
+						       MODULES_DOMAIN,
+						       NULL, 0, NULL,
+						       true);
+
+  /* Now search for all symbols of the required KIND matching the required
+     regular expressions.  We figure out which ones are in which modules
+     below.  */
+  std::vector<symbol_search> symbols = search_symbols (regexp, kind,
+						       type_regexp, 0,
+						       NULL, true);
+
+  /* Now iterate over all MODULES, checking to see which items from
+     SYMBOLS are in each module.  */
+  for (const symbol_search &p : modules)
+    {
+      QUIT;
+
+      /* This is a module.  */
+      gdb_assert (p.symbol != nullptr);
+
+      std::string prefix = SYMBOL_PRINT_NAME (p.symbol);
+      prefix += "::";
+
+      for (const symbol_search &q : symbols)
+	{
+	  if (q.symbol == nullptr)
+	    continue;
+
+	  if (strncmp (SYMBOL_PRINT_NAME (q.symbol), prefix.c_str (),
+		       prefix.size ()) != 0)
+	    continue;
+
+	  results.push_back ({p, q});
+	}
+    }
+
+  return results;
+}
+
+/* Implement the core of both 'info module functions' and 'info module
+   variables'.  */
+
+static void
+info_module_subcommand (bool quiet, const char *module_regexp,
+			const char *regexp, const char *type_regexp,
+			search_domain kind)
+{
+  /* Print a header line.  Don't build the header line bit by bit as this
+     prevents internationalisation.  */
+  if (!quiet)
+    {
+      if (module_regexp == nullptr)
+	{
+	  if (type_regexp == nullptr)
+	    {
+	      if (regexp == nullptr)
+		printf_filtered ((kind == VARIABLES_DOMAIN
+				  ? _("All variables in all modules:")
+				  : _("All functions in all modules:")));
+	      else
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables matching regular expression"
+			" \"%s\" in all modules:")
+		    : _("All functions matching regular expression"
+			" \"%s\" in all modules:")),
+		   regexp);
+	    }
+	  else
+	    {
+	      if (regexp == nullptr)
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables with type matching regular "
+			"expression \"%s\" in all modules:")
+		    : _("All functions with type matching regular "
+			"expression \"%s\" in all modules:")),
+		   type_regexp);
+	      else
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables matching regular expression "
+			"\"%s\",\n\twith type matching regular "
+			"expression \"%s\" in all modules:")
+		    : _("All functions matching regular expression "
+			"\"%s\",\n\twith type matching regular "
+			"expression \"%s\" in all modules:")),
+		   regexp, type_regexp);
+	    }
+	}
+      else
+	{
+	  if (type_regexp == nullptr)
+	    {
+	      if (regexp == nullptr)
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables in all modules matching regular "
+			"expression \"%s\":")
+		    : _("All functions in all modules matching regular "
+			"expression \"%s\":")),
+		   module_regexp);
+	      else
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables matching regular expression "
+			"\"%s\",\n\tin all modules matching regular "
+			"expression \"%s\":")
+		    : _("All functions matching regular expression "
+			"\"%s\",\n\tin all modules matching regular "
+			"expression \"%s\":")),
+		   regexp, module_regexp);
+	    }
+	  else
+	    {
+	      if (regexp == nullptr)
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables with type matching regular "
+			"expression \"%s\"\n\tin all modules matching "
+			"regular expression \"%s\":")
+		    : _("All functions with type matching regular "
+			"expression \"%s\"\n\tin all modules matching "
+			"regular expression \"%s\":")),
+		   type_regexp, module_regexp);
+	      else
+		printf_filtered
+		  ((kind == VARIABLES_DOMAIN
+		    ? _("All variables matching regular expression "
+			"\"%s\",\n\twith type matching regular expression "
+			"\"%s\",\n\tin all modules matching regular "
+			"expression \"%s\":")
+		    : _("All functions matching regular expression "
+			"\"%s\",\n\twith type matching regular expression "
+			"\"%s\",\n\tin all modules matching regular "
+			"expression \"%s\":")),
+		   regexp, type_regexp, module_regexp);
+	    }
+	}
+      printf_filtered ("\n");
+    }
+
+  /* Find all symbols of type KIND matching the given regular expressions
+     along with the symbols for the modules in which those symbols
+     reside.  */
+  std::vector<module_symbol_search> module_symbols
+    = search_module_symbols (module_regexp, regexp, type_regexp, kind);
+
+  std::sort (module_symbols.begin (), module_symbols.end (),
+	     [] (const module_symbol_search &a, const module_symbol_search &b)
+	     {
+	       if (a.first < b.first)
+		 return true;
+	       else if (a.first == b.first)
+		 return a.second < b.second;
+	       else
+		 return false;
+	     });
+
+  const char *last_filename = "";
+  const symbol *last_module_symbol = nullptr;
+  for (const module_symbol_search &ms : module_symbols)
+    {
+      const symbol_search &p = ms.first;
+      const symbol_search &q = ms.second;
+
+      gdb_assert (q.symbol != nullptr);
+
+      if (last_module_symbol != p.symbol)
+	{
+	  printf_filtered ("\n");
+	  printf_filtered (_("Module \"%s\":\n"),
+			   SYMBOL_PRINT_NAME (p.symbol));
+	  last_module_symbol = p.symbol;
+	  last_filename = "";
+	}
+
+      print_symbol_info (FUNCTIONS_DOMAIN, q.symbol, q.block,
+			 last_filename);
+      last_filename
+	= symtab_to_filename_for_display (symbol_symtab (q.symbol));
+    }
+}
+
+/* Hold the option values for the 'info module .....' sub-commands.  */
+
+struct info_modules_var_func_options
+{
+  bool quiet = false;
+  char *type_regexp = nullptr;
+  char *module_regexp = nullptr;
+
+  ~info_modules_var_func_options ()
+  {
+    xfree (type_regexp);
+    xfree (module_regexp);
+  }
+};
+
+/* The options used by 'info module variables' and 'info module functions'
+   commands.  */
+
+static const gdb::option::option_def info_modules_var_func_options_defs [] = {
+  gdb::option::boolean_option_def<info_modules_var_func_options> {
+    "q",
+    [] (info_modules_var_func_options *opt) { return &opt->quiet; },
+    nullptr, /* show_cmd_cb */
+    nullptr /* set_doc */
+  },
+
+  gdb::option::string_option_def<info_modules_var_func_options> {
+    "t",
+    [] (info_modules_var_func_options *opt) { return &opt->type_regexp; },
+    nullptr, /* show_cmd_cb */
+    nullptr /* set_doc */
+  },
+
+  gdb::option::string_option_def<info_modules_var_func_options> {
+    "m",
+    [] (info_modules_var_func_options *opt) { return &opt->module_regexp; },
+    nullptr, /* show_cmd_cb */
+    nullptr /* set_doc */
+  }
+};
+
+/* Return the option group used by the 'info module ...' sub-commands.  */
+
+static inline gdb::option::option_def_group
+make_info_modules_var_func_options_def_group
+	(info_modules_var_func_options *opts)
+{
+  return {{info_modules_var_func_options_defs}, opts};
+}
+
+/* Implements the 'info module functions' command.  */
+
+static void
+info_module_functions_command (const char *args, int from_tty)
+{
+  info_modules_var_func_options opts;
+  auto grp = make_info_modules_var_func_options_def_group (&opts);
+  gdb::option::process_options
+    (&args, gdb::option::PROCESS_OPTIONS_UNKNOWN_IS_OPERAND, grp);
+  if (args != nullptr && *args == '\0')
+    args = nullptr;
+
+  info_module_subcommand (opts.quiet, opts.module_regexp, args,
+			  opts.type_regexp, FUNCTIONS_DOMAIN);
+}
+
+/* Implements the 'info module variables' command.  */
+
+static void
+info_module_variables_command (const char *args, int from_tty)
+{
+  info_modules_var_func_options opts;
+  auto grp = make_info_modules_var_func_options_def_group (&opts);
+  gdb::option::process_options
+    (&args, gdb::option::PROCESS_OPTIONS_UNKNOWN_IS_OPERAND, grp);
+  if (args != nullptr && *args == '\0')
+    args = nullptr;
+
+  info_module_subcommand (opts.quiet, opts.module_regexp, args,
+			  opts.type_regexp, VARIABLES_DOMAIN);
+}
+
+/* Command completer for 'info module ...' sub-commands.  */
+
+static void
+info_module_var_func_command_completer (struct cmd_list_element *ignore,
+					completion_tracker &tracker,
+					const char *text,
+					const char * /* word */)
+{
+
+  const auto group = make_info_modules_var_func_options_def_group (nullptr);
+  if (gdb::option::complete_options
+      (tracker, &text, gdb::option::PROCESS_OPTIONS_UNKNOWN_IS_OPERAND, group))
+    return;
+
+  const char *word = advance_to_expression_complete_word_point (tracker, text);
+  symbol_completer (ignore, tracker, text, word);
+}
+
+
+
 void
 _initialize_symtab (void)
 {
@@ -6402,6 +6711,45 @@ Options:\n\
 		_("All module names, or those matching REGEXP."));
   set_cmd_completer_handle_brkchars (c, info_types_command_completer);
 
+  add_prefix_cmd ("module", class_info, info_module_command, _("\
+Print information about modules."),
+		  &info_module_cmdlist, "info module ",
+		  0, &infolist);
+
+  c = add_cmd ("functions", class_info, info_module_functions_command, _("\
+Display functions arranged by modules.\n\
+Usage: info module functions [-q] [-m MODREGEXP] [-t TYPEREGEXP] [REGEXP]\n\
+Print a summary of all functions within each Fortran module, grouped by\n\
+module and file.  For each function the line on which the function is\n\
+defined is given along with the type signature and name of the function.\n\
+\n\
+If REGEXP is provided then only functions whose name matches REGEXP are\n\
+listed.  If MODREGEXP is provided then only functions in modules matching\n\
+MODREGEXP are listed.  If TYPEREGEXP is given then only functions whose\n\
+type signature matches TYPEREGEXP are listed.\n\
+\n\
+The -q flag suppresses printing some header information."),
+	       &info_module_cmdlist);
+  set_cmd_completer_handle_brkchars
+    (c, info_module_var_func_command_completer);
+
+  c = add_cmd ("variables", class_info, info_module_variables_command, _("\
+Display variables arranged by modules.\n\
+Usage: info module variables [-q] [-m MODREGEXP] [-t TYPEREGEXP] [REGEXP]\n\
+Print a summary of all variables within each Fortran module, grouped by\n\
+module and file.  For each variable the line on which the variable is\n\
+defined is given along with the type and name of the variable.\n\
+\n\
+If REGEXP is provided then only variables whose name matches REGEXP are\n\
+listed.  If MODREGEXP is provided then only variables in modules matching\n\
+MODREGEXP are listed.  If TYPEREGEXP is given then only variables whose\n\
+type matches TYPEREGEXP are listed.\n\
+\n\
+The -q flag suppresses printing some header information."),
+	       &info_module_cmdlist);
+  set_cmd_completer_handle_brkchars
+    (c, info_module_var_func_command_completer);
+
   add_com ("rbreak", class_breakpoint, rbreak_command,
 	   _("Set a breakpoint for all functions matching REGEXP."));