Re: [RFC] Let "gcore" command accept a suffix argument

[Hui Zhu <teawater@gmail.com>]

On Sun, Jan 10, 2010 at 22:00, Joel Brobecker <brobecker@adacore.com> wrote:
>> But I think we have know the type of the val that we want output, the
>> string we want it as string, the number we want it to be number.
>> Are you sure we need point out the type of val to be output?
>>
>> And this idea is out of my ability.  Sorry about it.
>
> If you could have a look at how the "printf" command is implemented,
> you might be surprised as to how easy this task might be.  For someone
> who tackled the really complex project of grafting process record onto
> GDB, I sincerely think that this should nearly be a no-brainer for you:
>
>  1. Extract out the entire contents of the printf_command implementation
>     into a separate function. Let's call it ui_printf:
>
>       void
>       ui_printf (char *args, ui_file *stream)
>
>  2. Adjust the body so that all the printf/puts, etc, basically anything
>     printing on stdout, are replace by equivalent calls that print in
>     the given ui_file *stream;
>
>  3. Implement the body of printf_command by simply calling this new
>     function with gdb_stdout as the ui_file;
>
>       printf_command (char *args, int from_tty)
>       {
>         ui_printf (args, gdb_stout);
>       }
>
>  4. Implement the eval function roughly like so:
>
>        eval_command (char *args, int from_tty)
>        {
>          struct ui_file *ui_out = mem_fileopen ();
>          char *expanded;
>          struct cleanup *old_chain;
>
>          ui_printf (args, ui_out);  // That's the new function extracted
>                                     // from printf_command, which prints
>                                     // in a ui_file instead of stdout.
>          expanded = ui_file_xstrdup (ui_out, NULL);
>          old_chain = make_cleanup (xfree, expanded);
>          execute_command (expanded, from_tty);
>          do_cleanups (old_chain);
>        }
>
> --
> Joel
>

Hi Joel,

I make a new patch according to your mail.
Please help me review it.

Thanks,
Hui

2010-06-21  Hui Zhu  <teawater@gmail.com>

       * printcmd.c (ui_printf_maybe_filtered): New function.
       (printf_command): Call ui_printf_maybe_filtered.
       (_initialize_printcmd): New command "eval".


---
 printcmd.c |   96 ++++++++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 82 insertions(+), 14 deletions(-)

--- a/printcmd.c
+++ b/printcmd.c
@@ -1957,7 +1957,7 @@ print_variable_and_value (const char *na
 }

 static void
-printf_command (char *arg, int from_tty)
+ui_printf_maybe_filtered (char *arg, struct ui_file *stream, int filter)
 {
   char *f = NULL;
   char *s = arg;
@@ -2340,7 +2340,10 @@ printf_command (char *arg, int from_tty)
 		read_memory (tem, str, j);
 	      str[j] = 0;

-	      printf_filtered (current_substring, (char *) str);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, (char *) str);
+              else
+                fprintf_unfiltered (stream, current_substring, (char *) str);
 	    }
 	    break;
 	  case wide_string_arg:
@@ -2384,7 +2387,12 @@ printf_command (char *arg, int from_tty)
 					 &output, translit_char);
 	      obstack_grow_str0 (&output, "");

-	      printf_filtered (current_substring, obstack_base (&output));
+              if (filter)
+	        fprintf_filtered (stream, current_substring,
+                                  obstack_base (&output));
+              else
+                fprintf_unfiltered (stream, current_substring,
+                                    obstack_base (&output));
 	      do_cleanups (inner_cleanup);
 	    }
 	    break;
@@ -2416,7 +2424,12 @@ printf_command (char *arg, int from_tty)
 					 &output, translit_char);
 	      obstack_grow_str0 (&output, "");

-	      printf_filtered (current_substring, obstack_base (&output));
+              if (filter)
+	        fprintf_filtered (stream, current_substring,
+                                  obstack_base (&output));
+              else
+	        fprintf_unfiltered (stream, current_substring,
+                                    obstack_base (&output));
 	      do_cleanups (inner_cleanup);
 	    }
 	    break;
@@ -2433,7 +2446,10 @@ printf_command (char *arg, int from_tty)
 	      if (inv)
 		error (_("Invalid floating value found in program."));

-	      printf_filtered (current_substring, (double) val);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, (double) val);
+              else
+                fprintf_unfiltered (stream, current_substring, (double) val);
 	      break;
 	    }
 	  case long_double_arg:
@@ -2450,7 +2466,12 @@ printf_command (char *arg, int from_tty)
 	      if (inv)
 		error (_("Invalid floating value found in program."));

-	      printf_filtered (current_substring, (long double) val);
+              if (filter)
+	        fprintf_filtered (stream, current_substring,
+                                  (long double) val);
+              else
+	        fprintf_unfiltered (stream, current_substring,
+                                    (long double) val);
 	      break;
 	    }
 #else
@@ -2461,7 +2482,10 @@ printf_command (char *arg, int from_tty)
 	    {
 	      long long val = value_as_long (val_args[i]);

-	      printf_filtered (current_substring, val);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, val);
+              else
+                fprintf_unfiltered (stream, current_substring, val);
 	      break;
 	    }
 #else
@@ -2471,14 +2495,20 @@ printf_command (char *arg, int from_tty)
 	    {
 	      int val = value_as_long (val_args[i]);

-	      printf_filtered (current_substring, val);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, val);
+              else
+                fprintf_unfiltered (stream, current_substring, val);
 	      break;
 	    }
 	  case long_arg:
 	    {
 	      long val = value_as_long (val_args[i]);

-	      printf_filtered (current_substring, val);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, val);
+              else
+                fprintf_unfiltered (stream, current_substring, val);
 	      break;
 	    }

@@ -2490,7 +2520,10 @@ printf_command (char *arg, int from_tty)
 #if defined (PRINTF_HAS_DECFLOAT)
 	      /* If we have native support for Decimal floating
 		 printing, handle it here.  */
-	      printf_filtered (current_substring, param_ptr);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, param_ptr);
+              else
+                fprintf_unfiltered (stream, current_substring, param_ptr);
 #else

 	      /* As a workaround until vasprintf has native support for DFP
@@ -2579,7 +2612,10 @@ printf_command (char *arg, int from_tty)
 	      decimal_to_string (dfp_ptr, dfp_len, byte_order, decstr);

 	      /* Print the DFP value.  */
-	      printf_filtered (current_substring, decstr);
+              if (filter)
+	        fprintf_filtered (stream, current_substring, decstr);
+              else
+                fprintf_unfiltered (stream, current_substring, decstr);

 	      break;
 #endif
@@ -2634,13 +2670,19 @@ printf_command (char *arg, int from_tty)
 		  *fmt_p++ = 'l';
 		  *fmt_p++ = 'x';
 		  *fmt_p++ = '\0';
-		  printf_filtered (fmt, val);
+                  if (filter)
+		    fprintf_filtered (stream, fmt, val);
+                  else
+                    fprintf_unfiltered (stream, fmt, val);
 		}
 	      else
 		{
 		  *fmt_p++ = 's';
 		  *fmt_p++ = '\0';
-		  printf_filtered (fmt, "(nil)");
+                  if (filter)
+		    fprintf_filtered (stream, fmt, "(nil)");
+                  else
+                    fprintf_unfiltered (stream, fmt, "(nil)");
 		}

 	      break;
@@ -2658,11 +2700,34 @@ printf_command (char *arg, int from_tty)
        puts_filtered here.  Also, we pass a dummy argument because
        some platforms have modified GCC to include -Wformat-security
        by default, which will warn here if there is no argument.  */
-    printf_filtered (last_arg, 0);
+    if (filter)
+      fprintf_filtered (stream, last_arg, 0);
+    else
+      fprintf_unfiltered (stream, last_arg, 0);
   }
   do_cleanups (old_cleanups);
 }

+static void
+printf_command (char *arg, int from_tty)
+{
+  ui_printf_maybe_filtered (arg, gdb_stdout, 1);
+}
+
+static void
+eval_command (char *arg, int from_tty)
+{
+  struct ui_file *ui_out = mem_fileopen ();
+  char *expanded;
+  struct cleanup *old_chain;
+
+  ui_printf_maybe_filtered (arg, ui_out, 0);
+  expanded = ui_file_xstrdup (ui_out, NULL);
+  old_chain = make_cleanup (xfree, expanded);
+  execute_command (expanded, from_tty);
+  do_cleanups (old_chain);
+}
+
 void
 _initialize_printcmd (void)
 {
@@ -2826,4 +2891,7 @@ Show printing of source filename and lin
 			   NULL,
 			   show_print_symbol_filename,
 			   &setprintlist, &showprintlist);
+
+  add_com ("eval", no_class, eval_command, _("\
+Call command with variable."));
 }