This is the mail archive of the gdb-patches@sourceware.org mailing list for the GDB project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Add set/show display-linkname command


On 03/18/2013 06:21 PM, Michael Eager wrote:
It's sometimes useful to know what the linkage name is for a function,
either for C++ programs or on any target which can decorate symbols in
various ways, such as optionally prepending an underscore.

This patch adds two commands: "show display-linkname" and "set display-linkname".
When set, the linkname is displayed whenever the function is displayed in
in breakpoint command or when the frame is displayed.

The following shows a small C++ program hitting a breakpoint and running
a backtrace, with and without the linkage name.


$ gdb tpp
GNU gdb (GDB) 7.6.50.20130313-cvs
...
(gdb) show display-linkname
Whether to display linkage name for functions is off.
(gdb) b foo
Breakpoint 1 at 0x400a0c: file t.cpp, line 6.
(gdb) run
Starting program: /tmp/tpp

Breakpoint 1, foo (msg=...) at t.cpp:6
6         cout << msg;
(gdb) bt
#0  foo (msg=...) at t.cpp:6
#1  0x0000000000400a55 in main () at t.cpp:11
(gdb) set display-linkname on
(gdb) show display-linkname
Whether to display linkage name for functions is on.
(gdb) run
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Starting program: /tmp/tpp

Breakpoint 1, foo [_Z3fooSs] (msg=...) at t.cpp:6
6         cout << msg;
(gdb) bt
#0  foo [_Z3fooSs] (msg=...) at t.cpp:6
#1  0x0000000000400a55 in main [main] () at t.cpp:11
(gdb) quit


ChangeLog:

   * 2013-03-18  Michael Eager <eager@eagercon.com>

   * ada-lang.c (is_known_support_routine): Add linkname to find_frame_funname() call.
   * defs.h (build_address_symbolic): Add linkname arg.
   * disasm.c (dump_insns): Add linkname to find_frame_funname() call.
   * printcmd.c (top.h): Include.
   (MAX_LINKNAME_LEN): Define as 20.
   (print_address_symbolic): Add linkname to build_address_symbolic() call, print
   linkname if display-linkname set.
   (build_address_symbolic): Add linkname arg, set if different from symbol name.
   * stack.c (top.h): Include.
   (MAX_LINKNAME_LEN): Define as 20.
   (find_frame_funname): Add linkname arg, set if different from symbol name.
   (print_frame): Add linkname to  find_frame_funname() call, print linkname if
   display-linkname set.
   * stack.h (find_frame_funname): Add linkname arg.
   * top.c (disp_linkname): Define.
   (show_disp_linkname): New.
   (init_main): Add 'display-linkname' set/show command.
   * top.h (disp_linkname): Declare.
   * python/py-frame.c(frapy_name): Add linkname to find_frame_funname() call.

Updated patch which fixes garbled output.


--
Michael Eager	 eager@eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077
? .dwarf2read.c.swp
? common/signals.c-annotate
Index: ada-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/ada-lang.c,v
retrieving revision 1.397
diff -u -p -r1.397 ada-lang.c
--- ada-lang.c	13 Mar 2013 18:34:53 -0000	1.397
+++ ada-lang.c	21 Mar 2013 19:00:38 -0000
@@ -11107,6 +11107,7 @@ is_known_support_routine (struct frame_i
 {
   struct symtab_and_line sal;
   const char *func_name;
+  const char *linkname;
   enum language func_lang;
   int i;
   const char *fullname;
@@ -11145,7 +11146,7 @@ is_known_support_routine (struct frame_i
 
   /* Check whether the function is a GNAT-generated entity.  */
 
-  find_frame_funname (frame, &func_name, &func_lang, NULL);
+  find_frame_funname (frame, &func_name, &linkname, &func_lang, NULL);
   if (func_name == NULL)
     return 1;
 
@@ -11212,9 +11213,10 @@ ada_unhandled_exception_name_addr_from_r
   while (fi != NULL)
     {
       const char *func_name;
+      const char *linkname;
       enum language func_lang;
 
-      find_frame_funname (fi, &func_name, &func_lang, NULL);
+      find_frame_funname (fi, &func_name, &linkname, &func_lang, NULL);
       if (func_name != NULL
           && strcmp (func_name, data->exception_info->catch_exception_sym) == 0)
         break; /* We found the frame we were looking for...  */
Index: defs.h
===================================================================
RCS file: /cvs/src/src/gdb/defs.h,v
retrieving revision 1.329
diff -u -p -r1.329 defs.h
--- defs.h	4 Feb 2013 12:57:44 -0000	1.329
+++ defs.h	21 Mar 2013 19:00:38 -0000
@@ -335,6 +335,7 @@ extern int build_address_symbolic (struc
 				   CORE_ADDR addr,
 				   int do_demangle, 
 				   char **name, 
+				   char **linkname, 
 				   int *offset, 
 				   char **filename, 
 				   int *line, 	
Index: disasm.c
===================================================================
RCS file: /cvs/src/src/gdb/disasm.c,v
retrieving revision 1.51
diff -u -p -r1.51 disasm.c
--- disasm.c	11 Mar 2013 08:53:17 -0000	1.51
+++ disasm.c	21 Mar 2013 19:00:38 -0000
@@ -112,6 +112,7 @@ dump_insns (struct gdbarch *gdbarch, str
     {
       char *filename = NULL;
       char *name = NULL;
+      char *linkname = NULL;
 
       QUIT;
       if (how_many >= 0)
@@ -127,8 +128,8 @@ dump_insns (struct gdbarch *gdbarch, str
 	ui_out_text (uiout, pc_prefix (pc));
       ui_out_field_core_addr (uiout, "address", gdbarch, pc);
 
-      if (!build_address_symbolic (gdbarch, pc, 0, &name, &offset, &filename,
-				   &line, &unmapped))
+      if (!build_address_symbolic (gdbarch, pc, 0, &name, &linkname, &offset, 
+				   &filename, &line, &unmapped))
 	{
 	  /* We don't care now about line, filename and
 	     unmapped. But we might in the future.  */
Index: printcmd.c
===================================================================
RCS file: /cvs/src/src/gdb/printcmd.c,v
retrieving revision 1.225
diff -u -p -r1.225 printcmd.c
--- printcmd.c	13 Mar 2013 18:34:54 -0000	1.225
+++ printcmd.c	21 Mar 2013 19:00:38 -0000
@@ -51,11 +51,15 @@
 #include "cli/cli-utils.h"
 #include "format.h"
 #include "source.h"
+#include "top.h"
 
 #ifdef TUI
 #include "tui/tui.h"		/* For tui_active et al.   */
 #endif
 
+/* Maximum length of linkname to print.  */
+#define MAX_LINKNAME_LEN 20
+
 struct format_data
   {
     int count;
@@ -569,17 +573,18 @@ print_address_symbolic (struct gdbarch *
 			int do_demangle, char *leadin)
 {
   char *name = NULL;
+  char *linkname = NULL;
   char *filename = NULL;
   int unmapped = 0;
   int offset = 0;
   int line = 0;
 
-  /* Throw away both name and filename.  */
+  /* Throw away both name, linkname, and filename.  */
   struct cleanup *cleanup_chain = make_cleanup (free_current_contents, &name);
   make_cleanup (free_current_contents, &filename);
 
-  if (build_address_symbolic (gdbarch, addr, do_demangle, &name, &offset,
-			      &filename, &line, &unmapped))
+  if (build_address_symbolic (gdbarch, addr, do_demangle, &name, &linkname,
+			      &offset, &filename, &line, &unmapped))
     {
       do_cleanups (cleanup_chain);
       return 0;
@@ -591,6 +596,24 @@ print_address_symbolic (struct gdbarch *
   else
     fputs_filtered ("<", stream);
   fputs_filtered (name, stream);
+
+  /* Print linkage name after source name if requested.  */
+  if (disp_linkname && linkname)
+    {
+      char *lname = linkname;
+
+      if (strlen (lname) > MAX_LINKNAME_LEN) 
+        {
+          lname = alloca (MAX_LINKNAME_LEN + 4);
+	  strncpy (lname, linkname, MAX_LINKNAME_LEN);
+	  lname[MAX_LINKNAME_LEN] = '\0';
+	  strcat (lname, "...");
+ 	}
+      fputs_filtered (" [", stream);
+      fputs_filtered (lname, stream);
+      fputs_filtered ("]", stream);
+    }
+
   if (offset != 0)
     fprintf_filtered (stream, "+%u", (unsigned int) offset);
 
@@ -623,6 +646,7 @@ build_address_symbolic (struct gdbarch *
 			CORE_ADDR addr,  /* IN */
 			int do_demangle, /* IN */
 			char **name,     /* OUT */
+			char **linkname, /* OUT */
 			int *offset,     /* OUT */
 			char **filename, /* OUT */
 			int *line,       /* OUT */
@@ -637,6 +661,9 @@ build_address_symbolic (struct gdbarch *
   /* Let's say it is mapped (not unmapped).  */
   *unmapped = 0;
 
+  /* Let's say the link name is the same as the symbol name.  */
+  *linkname = 0;
+
   /* Determine if the address is in an overlay, and whether it is
      mapped.  */
   if (overlay_debugging)
@@ -729,6 +756,12 @@ build_address_symbolic (struct gdbarch *
 	  *line = sal.line;
 	}
     }
+
+  /* If we have both symbol names and they are different, let caller know.  */
+  if (msymbol && symbol 
+      && strcmp (SYMBOL_LINKAGE_NAME (msymbol), SYMBOL_LINKAGE_NAME (symbol)))
+    *linkname = xstrdup (SYMBOL_LINKAGE_NAME (msymbol));
+
   return 0;
 }
 
Index: stack.c
===================================================================
RCS file: /cvs/src/src/gdb/stack.c,v
retrieving revision 1.267
diff -u -p -r1.267 stack.c
--- stack.c	7 Mar 2013 21:57:30 -0000	1.267
+++ stack.c	21 Mar 2013 19:00:38 -0000
@@ -54,6 +54,10 @@
 
 #include "psymtab.h"
 #include "symfile.h"
+#include "top.h"
+
+/* Maximum length of linkname to print.  */
+#define MAX_LINKNAME_LEN 20
 
 void (*deprecated_selected_frame_level_changed_hook) (int);
 
@@ -1006,11 +1010,13 @@ get_last_displayed_sal (struct symtab_an
 
 void
 find_frame_funname (struct frame_info *frame, const char **funname,
-		    enum language *funlang, struct symbol **funcp)
+		    const char **linkname, enum language *funlang, 
+		    struct symbol **funcp)
 {
   struct symbol *func;
 
   *funname = NULL;
+  *linkname = NULL;
   *funlang = language_unknown;
   if (funcp)
     *funcp = NULL;
@@ -1044,6 +1050,10 @@ find_frame_funname (struct frame_info *f
 	msymbol
 	  = lookup_minimal_symbol_by_pc (get_frame_address_in_block (frame));
 
+      if (msymbol 
+	  && strcmp (SYMBOL_LINKAGE_NAME (msymbol), SYMBOL_LINKAGE_NAME (func)))
+	*linkname = SYMBOL_LINKAGE_NAME (msymbol);
+
       if (msymbol != NULL
 	  && (SYMBOL_VALUE_ADDRESS (msymbol)
 	      > BLOCK_START (SYMBOL_BLOCK_VALUE (func))))
@@ -1102,6 +1112,7 @@ print_frame (struct frame_info *frame, i
   struct gdbarch *gdbarch = get_frame_arch (frame);
   struct ui_out *uiout = current_uiout;
   const char *funname = NULL;
+  const char *linkname = NULL;
   enum language funlang = language_unknown;
   struct ui_file *stb;
   struct cleanup *old_chain, *list_chain;
@@ -1115,7 +1126,7 @@ print_frame (struct frame_info *frame, i
   stb = mem_fileopen ();
   old_chain = make_cleanup_ui_file_delete (stb);
 
-  find_frame_funname (frame, &funname, &funlang, &func);
+  find_frame_funname (frame, &funname, &linkname, &funlang, &func);
 
   annotate_frame_begin (print_level ? frame_relative_level (frame) : 0,
 			gdbarch, pc);
@@ -1149,6 +1160,22 @@ print_frame (struct frame_info *frame, i
   ui_out_wrap_hint (uiout, "   ");
   annotate_frame_args ();
       
+  /* Print linkage name after source name if requested.  */
+  if (disp_linkname && linkname) 
+    {
+      char *lname = (char *)linkname;
+
+      if (strlen (lname) > MAX_LINKNAME_LEN) 
+        {
+          lname = alloca (MAX_LINKNAME_LEN + 4);
+	  strncpy (lname, linkname, MAX_LINKNAME_LEN);
+	  strcat (lname, "...");
+ 	}
+      ui_out_text (uiout, " [");
+      ui_out_text (uiout, lname);
+      ui_out_text (uiout, "]");
+    }
+
   ui_out_text (uiout, " (");
   if (print_args)
     {
Index: stack.h
===================================================================
RCS file: /cvs/src/src/gdb/stack.h,v
retrieving revision 1.16
diff -u -p -r1.16 stack.h
--- stack.h	1 Jan 2013 06:32:51 -0000	1.16
+++ stack.h	21 Mar 2013 19:00:38 -0000
@@ -23,7 +23,8 @@
 void select_frame_command (char *level_exp, int from_tty);
 
 void find_frame_funname (struct frame_info *frame, const char **funname,
-			 enum language *funlang, struct symbol **funcp);
+			 const char **linkname, enum language *funlang, 
+			 struct symbol **funcp);
 
 typedef void (*iterate_over_block_arg_local_vars_cb) (const char *print_name,
 						      struct symbol *sym,
Index: top.c
===================================================================
RCS file: /cvs/src/src/gdb/top.c,v
retrieving revision 1.227
diff -u -p -r1.227 top.c
--- top.c	13 Mar 2013 18:34:54 -0000	1.227
+++ top.c	21 Mar 2013 19:00:38 -0000
@@ -296,6 +296,18 @@ quit_cover (void)
   quit_command ((char *) 0, 0);
 }
 #endif /* defined SIGHUP */
+
+/* Flag for whether we want to print linkage name for functions.  */
+
+int disp_linkname = 0;		/* Default is no. */
+static void
+show_disp_linkname (struct ui_file *file, int from_tty,
+	      struct cmd_list_element *c, const char *value)
+{
+  fprintf_filtered (file, _("\
+Whether to display linkage name for functions is %s.\n"),
+		    value);
+}
 
 /* Line number we are currently in, in a file which is being sourced.  */
 /* NOTE 1999-04-29: This variable will be static again, once we modify
@@ -1683,6 +1695,13 @@ When set, GDB uses the specified path to
                            set_gdb_datadir, NULL,
                            &setlist,
                            &showlist);
+
+  add_setshow_boolean_cmd ("display-linkname", class_support, &disp_linkname, _("\
+Set whether to display linkage name for functions."), _("\
+Show whether to display linkage name for functions."), NULL,
+			   NULL,
+ 			   show_disp_linkname,
+			   &setlist, &showlist);
 }
 
 void
Index: top.h
===================================================================
RCS file: /cvs/src/src/gdb/top.h,v
retrieving revision 1.36
diff -u -p -r1.36 top.h
--- top.h	7 Jan 2013 16:40:36 -0000	1.36
+++ top.h	21 Mar 2013 19:00:38 -0000
@@ -26,6 +26,7 @@ extern int saved_command_line_size;
 extern FILE *instream;
 extern int in_user_command;
 extern int confirm;
+extern int disp_linkname;
 extern char gdb_dirbuf[1024];
 extern int inhibit_gdbinit;
 extern char gdbinit[];
Index: python/py-frame.c
===================================================================
RCS file: /cvs/src/src/gdb/python/py-frame.c,v
retrieving revision 1.29
diff -u -p -r1.29 py-frame.c
--- python/py-frame.c	23 Jan 2013 19:59:11 -0000	1.29
+++ python/py-frame.c	21 Mar 2013 19:00:38 -0000
@@ -123,6 +123,7 @@ frapy_name (PyObject *self, PyObject *ar
 {
   struct frame_info *frame;
   const char *name;
+  const char *linkname;
   enum language lang;
   PyObject *result;
   volatile struct gdb_exception except;
@@ -131,7 +132,7 @@ frapy_name (PyObject *self, PyObject *ar
     {
       FRAPY_REQUIRE_VALID (self, frame);
 
-      find_frame_funname (frame, &name, &lang, NULL);
+      find_frame_funname (frame, &name, &linkname, &lang, NULL);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]