Per-inferior program arguments and io terminal

[Vladimir Prus <vladimir at codesourcery dot com>]

At present, 'set args' sets global program arguments -- for every inferior. So,
if you wish to debug multiple programs, and they have different arguments, things
are unpleasant -- arguments should be changed before running each program. The
same problem exists with tty setting. The latter is probably most important for
frontends.

This patch makes 'set args' and 'set inferior-tty' be per-inferior. No regressions
on i686 linux. OK?

- Volodya

commit 62c539aad84bf40129de8c8e1232af7c332885b1
Author: Vladimir Prus <vladimir@codesourcery.com>
Date:   Mon Dec 21 15:28:03 2009 +0300

    Per-inferior args and tty.
    
    	* infcmd.c (inferior_args): Rename to ...
    	(inferior_args_sctach): ... this.
    	(inferior_io_terminal): Rename to ...
    	(inferior_io_terminal_scratch): ... this.
    	(inferior_argc, inferior_argv): Remove.
    	(set_inferior_io_terminal, get_inferior_io_terminal): Store
    	inside current_inferior().
    	(notice_inferior_io_terminal_set, show_inferior_io_terminal): New.
    	(get_inferior_args, set_inferior_args): Store inside
    	current_inferior().
    	(set_inferior_args_vector, notice_args_set): Likewise.
    	(tty_command): Remove.
    	(run_command_1): Don't free old args, as they are feed by
    	set_inferior_arg now.
    	(run_no_args_command): Likewise.
    	(_initialize_infcmd): Adjust variables.
    	* inferior.h (set_inferior_arg): Adjust prototype.
    	(struct inferior): New fields args, argc, argv, terminal.
    	* main.c (captured_main): Set arguments only after the initial
    	inferior has been created.  Set set_inferior_io_terminal,
    	not tty_command.

diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 21a2233..f0804b8 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -126,20 +126,17 @@ void _initialize_infcmd (void);
 #define ERROR_NO_INFERIOR \
    if (!target_has_execution) error (_("The program is not being run."));
 
-/* String containing arguments to give to the program, separated by spaces.
-   Empty string (pointer to '\0') means no args.  */
+/* Scratch area where string containing arguments to give to the program will be 
+   stored by 'set args'.  As soon as anything is stored, notice_args_set will
+   move it into per-inferior storage.  Arguments are separated by spaces. Empty
+   string (pointer to '\0') means no args.  */
 
-static char *inferior_args;
+static char *inferior_args_scratch;
 
-/* The inferior arguments as a vector.  If INFERIOR_ARGC is nonzero,
-   then we must compute INFERIOR_ARGS from this (via the target).  */
+/* Scratch area where 'set inferior-tty' will store user-provided value.
+   We'll immediate copy it into per-inferior storage.  */
 
-static int inferior_argc;
-static char **inferior_argv;
-
-/* File name for default use for standard in/out in the inferior.  */
-
-static char *inferior_io_terminal;
+static char *inferior_io_terminal_scratch;
 
 /* Pid of our debugged inferior, or 0 if no inferior now.
    Since various parts of infrun.c test this to see whether there is a program
@@ -176,64 +173,74 @@ struct gdb_environ *inferior_environ;
 void 
 set_inferior_io_terminal (const char *terminal_name)
 {
-  if (inferior_io_terminal)
-    xfree (inferior_io_terminal);
-
-  if (!terminal_name)
-    inferior_io_terminal = NULL;
-  else
-    inferior_io_terminal = xstrdup (terminal_name);
+  xfree (current_inferior ()->terminal);
+  current_inferior ()->terminal = terminal_name ? xstrdup (terminal_name) : 0;
 }
 
 const char *
 get_inferior_io_terminal (void)
 {
-  return inferior_io_terminal;
+  return current_inferior ()->terminal;
+}
+
+static void
+notice_inferior_io_terminal_set (char *args, int from_tty, struct cmd_list_element *c)
+{
+  /* CLI has assigned the user-provided value to inferior_io_terminal_scratch.
+     Now route it to current inferior.  */
+  set_inferior_io_terminal (inferior_io_terminal_scratch);
+}
+
+static void
+show_inferior_io_terminal (struct ui_file *file, int from_tty,
+			   struct cmd_list_element *c, const char *value)
+{
+  /* Note that we ignore the passed-in value in favor of computing it
+     directly.  */
+  deprecated_show_value_hack (file, from_tty, c, get_inferior_io_terminal ());
 }
 
 char *
 get_inferior_args (void)
 {
-  if (inferior_argc != 0)
+  if (current_inferior ()->argc != 0)
     {
       char *n, *old;
 
-      n = construct_inferior_arguments (inferior_argc, inferior_argv);
-      old = set_inferior_args (n);
-      xfree (old);
+      n = construct_inferior_arguments (current_inferior ()->argc, 
+					current_inferior ()->argv);
+      set_inferior_args (n);
     }
 
-  if (inferior_args == NULL)
-    inferior_args = xstrdup ("");
+  if (current_inferior ()->args == NULL)
+    current_inferior ()->args = xstrdup ("");
 
-  return inferior_args;
+  return current_inferior ()->args;
 }
 
-char *
+void
 set_inferior_args (char *newargs)
 {
-  char *saved_args = inferior_args;
-
-  inferior_args = newargs;
-  inferior_argc = 0;
-  inferior_argv = 0;
-
-  return saved_args;
+  xfree (current_inferior ()->args);
+  current_inferior ()->args = xstrdup (newargs ? newargs : "");
+  current_inferior ()->argc = 0;
+  current_inferior ()->argv = 0;
 }
 
 void
 set_inferior_args_vector (int argc, char **argv)
 {
-  inferior_argc = argc;
-  inferior_argv = argv;
+  current_inferior ()->argc = argc;
+  current_inferior ()->argv = argv;
 }
 
 /* Notice when `set args' is run.  */
 static void
 notice_args_set (char *args, int from_tty, struct cmd_list_element *c)
 {
-  inferior_argc = 0;
-  inferior_argv = 0;
+  /* CLI has assigned the user-provided value to inferior_args_scratch.
+     Now route it to current inferior.  */
+  set_inferior_args (inferior_args_scratch);
 }
 
 /* Notice when `show args' is run.  */
@@ -369,15 +376,6 @@ strip_bg_char (char **args)
   return 0;
 }
 
-void
-tty_command (char *file, int from_tty)
-{
-  if (file == 0)
-    error_no_arg (_("terminal name for running target process"));
-
-  set_inferior_io_terminal (file);
-}
-
 /* Common actions to take after creating any sort of inferior, by any
    means (running, attaching, connecting, et cetera).  The target
    should be stopped.  */
@@ -536,10 +534,7 @@ run_command_1 (char *args, int from_tty, int tbreak_at_main)
 
       /* If there were other args, beside '&', process them. */
       if (args)
-	{
-          char *old_args = set_inferior_args (xstrdup (args));
-          xfree (old_args);
-	}
+	set_inferior_args (xstrdup (args));
     }
 
   if (from_tty)
@@ -594,8 +589,7 @@ run_command (char *args, int from_tty)
 static void
 run_no_args_command (char *args, int from_tty)
 {
-  char *old_args = set_inferior_args (xstrdup (""));
-  xfree (old_args);
+  set_inferior_args (xstrdup (""));
 }
 
 
@@ -2646,14 +2640,17 @@ _initialize_infcmd (void)
 
   /* add the filename of the terminal connected to inferior I/O */
   add_setshow_filename_cmd ("inferior-tty", class_run,
-			    &inferior_io_terminal, _("\
+			    &inferior_io_terminal_scratch, _("\
 Set terminal for future runs of program being debugged."), _("\
 Show terminal for future runs of program being debugged."), _("\
-Usage: set inferior-tty /dev/pts/1"), NULL, NULL, &setlist, &showlist);
+Usage: set inferior-tty /dev/pts/1"), 
+			    notice_inferior_io_terminal_set, 
+			    show_inferior_io_terminal, 
+			    &setlist, &showlist);
   add_com_alias ("tty", "set inferior-tty", class_alias, 0);
 
   add_setshow_optional_filename_cmd ("args", class_run,
-				     &inferior_args, _("\
+				     &inferior_args_scratch, _("\
 Set argument list to give program being debugged when it is started."), _("\
 Show argument list to give program being debugged when it is started."), _("\
 Follow this command with any number of args, to be passed to the program."),
diff --git a/gdb/inferior.h b/gdb/inferior.h
index 9798ef1..048fc11 100644
--- a/gdb/inferior.h
+++ b/gdb/inferior.h
@@ -261,7 +261,7 @@ extern void attach_command (char *, int);
 
 extern char *get_inferior_args (void);
 
-extern char *set_inferior_args (char *);
+extern void set_inferior_args (char *);
 
 extern void set_inferior_args_vector (int, char **);
 
@@ -427,6 +427,18 @@ struct inferior
   /* The program space bound to this inferior.  */
   struct program_space *pspace;
 
+  /* The arguments string to use when running.  */
+  char *args;
+
+  /* The size of elements in argv.  */
+  int argc;
+
+  /* The vector version of arguments.  */
+  char **argv;
+
+  /* The name of terminal device to use for I/O.  */
+  char *terminal;
+
   /* See the definition of stop_kind above.  */
   enum stop_kind stop_soon;
 
diff --git a/gdb/main.c b/gdb/main.c
index 0cc0f75..e9f3857 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -631,54 +631,6 @@ extern int gdbtk_test (char *);
 	use_windows = 0;
       }
 
-    if (set_args)
-      {
-	/* The remaining options are the command-line options for the
-	   inferior.  The first one is the sym/exec file, and the rest
-	   are arguments.  */
-	if (optind >= argc)
-	  {
-	    fprintf_unfiltered (gdb_stderr,
-				_("%s: `--args' specified but no program specified\n"),
-				argv[0]);
-	    exit (1);
-	  }
-	symarg = argv[optind];
-	execarg = argv[optind];
-	++optind;
-	set_inferior_args_vector (argc - optind, &argv[optind]);
-      }
-    else
-      {
-	/* OK, that's all the options.  */
-
-	/* The first argument, if specified, is the name of the
-	   executable.  */
-	if (optind < argc)
-	  {
-	    symarg = argv[optind];
-	    execarg = argv[optind];
-	    optind++;
-	  }
-
-	/* If the user hasn't already specified a PID or the name of a
-	   core file, then a second optional argument is allowed.  If
-	   present, this argument should be interpreted as either a
-	   PID or a core file, whichever works.  */
-	if (pidarg == NULL && corearg == NULL && optind < argc)
-	  {
-	    pid_or_core_arg = argv[optind];
-	    optind++;
-	  }
-
-	/* Any argument left on the command line is unexpected and
-	   will be ignored.  Inform the user.  */
-	if (optind < argc)
-	  fprintf_unfiltered (gdb_stderr, _("\
-Excess command line arguments ignored. (%s%s)\n"),
-			      argv[optind],
-			      (optind == argc - 1) ? "" : " ...");
-      }
     if (batch)
       quiet = 1;
   }
@@ -687,6 +639,57 @@ Excess command line arguments ignored. (%s%s)\n"),
      control of the console via the deprecated_init_ui_hook ().  */
   gdb_init (argv[0]);
 
+  /* Now that gdb_init has created the initial inferior, we're in position
+     to set args for that inferior.  */
+  if (set_args)
+    {
+      /* The remaining options are the command-line options for the
+	 inferior.  The first one is the sym/exec file, and the rest
+	 are arguments.  */
+      if (optind >= argc)
+	{
+	  fprintf_unfiltered (gdb_stderr,
+			      _("%s: `--args' specified but no program specified\n"),
+			      argv[0]);
+	  exit (1);
+	}
+      symarg = argv[optind];
+      execarg = argv[optind];
+      ++optind;
+      set_inferior_args_vector (argc - optind, &argv[optind]);
+    }
+  else
+    {
+      /* OK, that's all the options.  */
+      
+      /* The first argument, if specified, is the name of the
+	 executable.  */
+      if (optind < argc)
+	{
+	  symarg = argv[optind];
+	  execarg = argv[optind];
+	  optind++;
+	}
+      
+      /* If the user hasn't already specified a PID or the name of a
+	 core file, then a second optional argument is allowed.  If
+	 present, this argument should be interpreted as either a
+	 PID or a core file, whichever works.  */
+      if (pidarg == NULL && corearg == NULL && optind < argc)
+	{
+	  pid_or_core_arg = argv[optind];
+	  optind++;
+	}
+      
+      /* Any argument left on the command line is unexpected and
+	 will be ignored.  Inform the user.  */
+      if (optind < argc)
+	fprintf_unfiltered (gdb_stderr, _("\
+Excess command line arguments ignored. (%s%s)\n"),
+			    argv[optind],
+			    (optind == argc - 1) ? "" : " ...");
+    }
+
   /* Lookup gdbinit files. Note that the gdbinit file name may be overriden
      during file initialization, so get_init_files should be called after
      gdb_init.  */
@@ -840,7 +843,7 @@ Can't attach to process and specify a core file at the same time."));
     }
 
   if (ttyarg != NULL)
-    catch_command_errors (tty_command, ttyarg, !batch, RETURN_MASK_ALL);
+    set_inferior_io_terminal (ttyarg);
 
   /* Error messages should no longer be distinguished with extra output. */
   error_pre_print = NULL;