gdb

* value.c (release_value): Clear 'next' pointer. * breakpoint.c (watch_command_1): Add 'just_location' argument. (watch_command_wrapper): Update. (watch_maybe_just_location): New function. (watch_command): Update. (rwatch_command_wrapper): Update. (rwatch_command): Update. (awatch_command_wrapper): Update. (awatch_command): Update. (check_for_argument): New function. (_initialize_breakpoint): Update help text. gdb/testsuite * gdb.base/help.exp: Update. * gdb.base/watchpoint.exp (test_watchpoint_and_breakpoint): Delete watchpoint. (test_watch_location): New proc. (test_watchpoint_in_big_blob): Delete watchpoint. * gdb.base/watchpoint.c (func5): New function. (main): Call it. gdb/doc * gdb.texinfo (Set Watchpoints): Document -location option.
2010-08-16 19:19:22 +00:00
parent 70ebf4ed1a
commit 06a64a0b78
9 changed files with 159 additions and 25 deletions
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -98,8 +98,6 @@ static void clear_command (char *, int);

 static void catch_command (char *, int);

-static void watch_command (char *, int);
-
 static int can_use_hardware_watchpoint (struct value *);

 static void break_command_1 (char *, int, int);
@@ -173,12 +171,6 @@ static void hbreak_command (char *, int);

 static void thbreak_command (char *, int);

-static void watch_command_1 (char *, int, int);
-
-static void rwatch_command (char *, int);
-
-static void awatch_command (char *, int);
-
 static void do_enable_breakpoint (struct breakpoint *, enum bpdisp);

 static void stop_command (char *arg, int from_tty);
@@ -7995,7 +7987,7 @@ watchpoint_exp_is_const (const struct expression *exp)
                hw_read:   watch read, 
 		hw_access: watch access (read or write) */
 static void
-watch_command_1 (char *arg, int accessflag, int from_tty)
+watch_command_1 (char *arg, int accessflag, int from_tty, int just_location)
 {
  struct breakpoint *b, *scope_breakpoint = NULL;
  struct expression *exp;
@@ -8100,7 +8092,15 @@ watch_command_1 (char *arg, int accessflag, int from_tty)
  exp_valid_block = innermost_block;
  mark = value_mark ();
  fetch_subexp_value (exp, &pc, &val, NULL, NULL);
-  if (val != NULL)
+
+  if (just_location)
+    {
+      exp_valid_block = NULL;
+      val = value_addr (val);
+      release_value (val);
+      value_free_to_mark (mark);
+    }
+  else if (val != NULL)
    release_value (val);

  tok = arg;
@@ -8202,7 +8202,24 @@ watch_command_1 (char *arg, int accessflag, int from_tty)
  b->exp = exp;
  b->exp_valid_block = exp_valid_block;
  b->cond_exp_valid_block = cond_exp_valid_block;
-  b->exp_string = savestring (exp_start, exp_end - exp_start);
+  if (just_location)
+    {
+      struct type *t = value_type (val);
+      CORE_ADDR addr = value_as_address (val);
+      char *name;
+
+      t = check_typedef (TYPE_TARGET_TYPE (check_typedef (t)));
+      name = type_to_string (t);
+
+      b->exp_string = xstrprintf ("* (%s *) %s", name,
+				  core_addr_to_string (addr));
+      xfree (name);
+
+      /* The above expression is in C.  */
+      b->language = language_c;
+    }
+  else
+    b->exp_string = savestring (exp_start, exp_end - exp_start);
  b->val = val;
  b->val_valid = 1;
  if (cond_start)
@@ -8229,7 +8246,8 @@ watch_command_1 (char *arg, int accessflag, int from_tty)
      scope_breakpoint->related_breakpoint = b;
    }

-  value_free_to_mark (mark);
+  if (!just_location)
+    value_free_to_mark (mark);

  /* Finally update the new watchpoint.  This creates the locations
     that should be inserted.  */
@@ -8319,37 +8337,73 @@ can_use_hardware_watchpoint (struct value *v)
 void
 watch_command_wrapper (char *arg, int from_tty)
 {
-  watch_command (arg, from_tty);
+  watch_command_1 (arg, hw_write, from_tty, 0);
+}
+
+/* A helper function that looks for an argument at the start of a
+   string.  The argument must also either be at the end of the string,
+   or be followed by whitespace.  Returns 1 if it finds the argument,
+   0 otherwise.  If the argument is found, it updates *STR.  */
+
+static int
+check_for_argument (char **str, char *arg, int arg_len)
+{
+  if (strncmp (*str, arg, arg_len) == 0
+      && ((*str)[arg_len] == '\0' || isspace ((*str)[arg_len])))
+    {
+      *str += arg_len;
+      return 1;
+    }
+  return 0;
+}
+
+/* A helper function that looks for the "-location" argument and then
+   calls watch_command_1.  */
+
+static void
+watch_maybe_just_location (char *arg, int accessflag, int from_tty)
+{
+  int just_location = 0;
+
+  if (arg
+      && (check_for_argument (&arg, "-location", sizeof ("-location") - 1)
+	  || check_for_argument (&arg, "-l", sizeof ("-l") - 1)))
+    {
+      ep_skip_leading_whitespace (&arg);
+      just_location = 1;
+    }
+
+  watch_command_1 (arg, accessflag, from_tty, just_location);
 }

 static void
 watch_command (char *arg, int from_tty)
 {
-  watch_command_1 (arg, hw_write, from_tty);
+  watch_maybe_just_location (arg, hw_write, from_tty);
 }

 void
 rwatch_command_wrapper (char *arg, int from_tty)
 {
-  rwatch_command (arg, from_tty);
+  watch_command_1 (arg, hw_read, from_tty, 0);
 }

 static void
 rwatch_command (char *arg, int from_tty)
 {
-  watch_command_1 (arg, hw_read, from_tty);
+  watch_maybe_just_location (arg, hw_read, from_tty);
 }

 void
 awatch_command_wrapper (char *arg, int from_tty)
 {
-  awatch_command (arg, from_tty);
+  watch_command_1 (arg, hw_access, from_tty, 0);
 }

 static void
 awatch_command (char *arg, int from_tty)
 {
-  watch_command_1 (arg, hw_access, from_tty);
+  watch_maybe_just_location (arg, hw_access, from_tty);
 }


@@ -11847,20 +11901,29 @@ With an argument, catch only exceptions with the given name."),

  c = add_com ("watch", class_breakpoint, watch_command, _("\
 Set a watchpoint for an expression.\n\
+Usage: watch [-l|-location] EXPRESSION\n\
 A watchpoint stops execution of your program whenever the value of\n\
-an expression changes."));
+an expression changes.\n\
+If -l or -location is given, this evaluates EXPRESSION and watches\n\
+the memory to which it refers."));
  set_cmd_completer (c, expression_completer);

  c = add_com ("rwatch", class_breakpoint, rwatch_command, _("\
 Set a read watchpoint for an expression.\n\
+Usage: rwatch [-l|-location] EXPRESSION\n\
 A watchpoint stops execution of your program whenever the value of\n\
-an expression is read."));
+an expression is read.\n\
+If -l or -location is given, this evaluates EXPRESSION and watches\n\
+the memory to which it refers."));
  set_cmd_completer (c, expression_completer);

  c = add_com ("awatch", class_breakpoint, awatch_command, _("\
 Set a watchpoint for an expression.\n\
+Usage: awatch [-l|-location] EXPRESSION\n\
 A watchpoint stops execution of your program whenever the value of\n\
-an expression is either read or written."));
+an expression is either read or written.\n\
+If -l or -location is given, this evaluates EXPRESSION and watches\n\
+the memory to which it refers."));
  set_cmd_completer (c, expression_completer);

  add_info ("watchpoints", watchpoints_info, _("\