Allow multiple browser commands on one line, separated by semicolons.

Estimated hours taken: 3

Allow multiple browser commands on one line, separated by semicolons.

trace/mercury_trace_internal.c:
trace/mercury_trace_internal.h:
	Separate the code for splitting lines and checking for EOF into
	a new function, MR_trace_get_command.

browser/parse.m:
	Call util__trace_get_command to read each command.

browser/util.m:
	Implement util__trace_get_command, which calls the function
	in the trace directory via an indirect pointer.

runtime/mercury_init.h:
runtime/mercury_wrapper.c:
runtime/mercury_wrapper.h:
util/mkinit.c:
	Set up the indirect pointer to the new function.

tests/debugger/browser_test.inp:
tests/debugger/browser_test.exp:
tests/debugger/browser_test.exp2:
	Test the new feature.

browser/parse.m

@@ -136,22 +136,13 @@
 	.
 
 parse__read_command(Prompt, Comm) -->
-	util__trace_getline(Prompt, Result),
-	( { Result = ok(Line) },
-		{ string__to_char_list(Line, Cs) },
-		{ lexer(Cs, Tokens) },
-		( { parse(Tokens, Comm2) } ->
-			{ Comm = Comm2 }
-		;
-			{ Comm = unknown }
-		)
-	; { Result = eof },
-		{ Comm = quit }
-	; { Result = error(Error) },
-		{ io__error_message(Error, Msg) },
-		io__write_string(Msg),
-		io__nl,
-		parse__read_command(Prompt, Comm)
+	util__trace_get_command(Prompt, Line),
+	{ string__to_char_list(Line, Cs) },
+	{ lexer(Cs, Tokens) },
+	( { parse(Tokens, Comm2) } ->
+		{ Comm = Comm2 }
+	;
+		{ Comm = unknown }
 	).
 
 parse__read_command_external(Comm) -->

browser/util.m

@@ -46,6 +46,16 @@
 		io__output_stream, io__state, io__state).
 :- mode util__trace_getline(in, out, in, in, di, uo) is det.
 
+	% trace_get_command is similar to trace_getline except that it
+	% breaks lines into semicolon separated commands, and replaces
+	% EOF with the command 'quit'.
+:- pred util__trace_get_command(string, string, io__state, io__state).
+:- mode util__trace_get_command(in, out, di, uo) is det.
+
+:- pred util__trace_get_command(string, string, io__input_stream,
+		io__output_stream, io__state, io__state).
+:- mode util__trace_get_command(in, out, in, in, di, uo) is det.
+
 :- pred util__zip_with(pred(T1, T2, T3), list(T1), list(T2), list(T3)).
 :- mode util__zip_with(pred(in, in, out) is det, in, in, out) is det.
 
@@ -113,6 +123,37 @@ util__trace_getline(Prompt, Result, MdbIn, MdbOut) -->
 	"
 ).
 
+util__trace_get_command(Prompt, Result) -->
+	io__input_stream(MdbIn),
+	io__output_stream(MdbOut),
+	util__trace_get_command(Prompt, Result, MdbIn, MdbOut).
+
+:- pragma c_code(util__trace_get_command(Prompt::in, Line::out, MdbIn::in,
+			MdbOut::in, State0::di, State::uo),
+	[will_not_call_mercury],
+	"
+		char		*line;
+		char		*mercury_string;
+		MercuryFile	*mdb_in = (MercuryFile *) MdbIn;
+		MercuryFile	*mdb_out = (MercuryFile *) MdbOut;
+
+		if (MR_address_of_trace_getline != NULL) {
+			line = (*MR_address_of_trace_get_command)(
+					(char *) Prompt,
+					MR_file(*mdb_in), MR_file(*mdb_out));
+		} else {
+			MR_tracing_not_enabled();
+			/* not reached */
+		}
+
+		MR_make_aligned_string_copy(mercury_string, line);
+		free(line);
+		Line = (String) mercury_string;
+
+		State = State0;
+	"
+).
+
 util__zip_with(Pred, XXs, YYs, Zipped) :-
 	( (XXs = [], YYs = []) ->
 		Zipped = []

runtime/mercury_init.h

@@ -121,6 +121,7 @@ extern	void	ML_io_print_to_cur_stream(MR_Word, MR_Box);
 
 /* in trace/mercury_trace_internal.h */
 extern	char	*MR_trace_getline(const char *, FILE *mdb_in, FILE *mdb_out);
+extern	char	*MR_trace_get_command(const char *, FILE *, FILE *);
 
 /* in trace/mercury_trace_external.h */
 extern	void	MR_trace_init_external(void);

runtime/mercury_wrapper.c

@@ -175,6 +175,7 @@ void	(*address_of_init_modules)(void);
 int	(*MR_address_of_do_load_aditi_rl_code)(void);
 
 char *	(*MR_address_of_trace_getline)(const char *, FILE *, FILE *);
+char *	(*MR_address_of_trace_get_command)(const char *, FILE *, FILE *);
 
 #ifdef	MR_USE_EXTERNAL_DEBUGGER
 void	(*MR_address_of_trace_init_external)(void);

runtime/mercury_wrapper.h

@@ -89,14 +89,17 @@ extern	void		(*address_of_init_gc)(void);
 extern	int		(*MR_address_of_do_load_aditi_rl_code)(void);
 
 /*
-** MR_trace_getline(const char *, FILE *, FILE *) is defined in
-** trace/mercury_trace_internal.c but is called in browser/util.m.  As
-** we cannot do direct calls from browser/ to trace/, we do an indirect 
-** call via the following pointer.
+** MR_trace_getline(const char *, FILE *, FILE *) and
+** MR_trace_get_command(const char *, FILE *, FILE *) are defined in
+** trace/mercury_trace_internal.c but are called in browser/util.m.  As
+** we cannot do direct calls from browser/ to trace/, we do indirect 
+** calls via the following pointers.
 */
 
 extern	char *		(*MR_address_of_trace_getline)(const char *,
 				FILE *, FILE *);
+extern	char *		(*MR_address_of_trace_get_command)(const char *,
+				FILE *, FILE *);
 
 /*
 ** MR_trace_init_external() and MR_trace_final_external() are defined 

tests/debugger/browser_test.exp

@@ -5,10 +5,8 @@ mdb> goto 3
        3:      2  2 EXIT pred browser_test:big_data/1-0 (det) browser_test.m:18 (browser_test.m:12)
 mdb> print *
        HeadVar__1             	big(big(big(small, 1, small), 2, small), 3, big(big(small, 4, big/3), 6, small))
-mdb> browse 1
-browser> print
+mdb> browse 1; print; quit
 big(big(big(small, 1, small), 2, small), 3, big(big(small, 4, big/3), 6, small))
-browser> quit
 mdb> browse HeadVar__1
 browser> ls
 big

tests/debugger/browser_test.exp2

@@ -5,10 +5,8 @@ mdb> goto 3
        3:      2  2 EXIT pred browser_test:big_data/1-0 (det) browser_test.m:18 (browser_test.m:12)
 mdb> print *
        HeadVar__1             	big(big(big(small, 1, small), 2, small), 3, big(big(small, 4, big/3), 6, small))
-mdb> browse 1
-browser> print
+mdb> browse 1; print; quit
 big(big(big(small, 1, small), 2, small), 3, big(big(small, 4, big/3), 6, small))
-browser> quit
 mdb> browse HeadVar__1
 browser> ls
 big

tests/debugger/browser_test.inp

@@ -1,9 +1,7 @@
 echo on
 goto 3
 print *
-browse 1
-print
-quit
+browse 1; print; quit
 browse HeadVar__1
 ls
 cd /1

trace/mercury_trace_internal.c

@@ -250,7 +250,7 @@ MR_trace_event_internal(MR_Trace_Cmd_Info *cmd, bool interactive,
 	jumpaddr = NULL;
 
 	do {
-		line = MR_trace_getline("mdb> ", MR_mdb_in, MR_mdb_out);
+		line = MR_trace_get_command("mdb> ", MR_mdb_in, MR_mdb_out);
 		res = MR_trace_debug_cmd(line, cmd, event_info, &event_details,
 				&jumpaddr);
 	} while (res == KEEP_INTERACTING);
@@ -484,28 +484,8 @@ MR_trace_debug_cmd(char *line, MR_Trace_Cmd_Info *cmd,
 	int		word_max;
 	int		word_count;
 	const char	*problem;
-	char		*semicolon;
 	MR_Next		next;
 
-	if (line == NULL) {
-		/*
-		** We got an EOF.
-		** We arrange things so we don't have to treat this case
-		** specially in the command interpreter below.
-		*/
-		line = MR_copy_string("quit");
-	}
-
-	if ((semicolon = strchr(line, ';')) != NULL) {
-		/*
-		** The line contains at least two commands.
-		** Execute only the first command now; put the others
-		** back in the input to be processed later.
-		*/
-		*semicolon = '\0';
-		MR_insert_line_at_head(MR_copy_string(semicolon + 1));
-	}
-
 	problem = MR_trace_parse_line(line, &words, &word_max, &word_count);
 	if (problem != NULL) {
 		fflush(MR_mdb_out);
@@ -2309,6 +2289,36 @@ MR_trace_source_from_open_file(FILE *fp)
 	MR_trace_internal_interacting = FALSE;
 }
 
+char *
+MR_trace_get_command(const char *prompt, FILE *mdb_in, FILE *mdb_out)
+{
+	char		*line;
+	char		*semicolon;
+
+	line = MR_trace_getline(prompt, mdb_in, mdb_out);
+
+	if (line == NULL) {
+		/*
+		** We got an EOF.
+		** We arrange things so we don't have to treat this case
+		** specially in the command interpreter below.
+		*/
+		line = MR_copy_string("quit");
+	}
+
+	if ((semicolon = strchr(line, ';')) != NULL) {
+		/*
+		** The line contains at least two commands.
+		** Execute only the first command now; put the others
+		** back in the input to be processed later.
+		*/
+		*semicolon = '\0';
+		MR_insert_line_at_head(MR_copy_string(semicolon + 1));
+	}
+
+	return line;
+}
+
 /*
 ** If there any lines waiting in the queue, return the first of these.
 ** If not, print the prompt to mdb_out, read a line from mdb_in,

trace/mercury_trace_internal.h

@@ -64,5 +64,7 @@ extern	void	MR_trace_interrupt_message(void);
 
 extern	char	*MR_trace_getline(const char *prompt, FILE *mdb_in,
 				FILE *mdb_out);
+extern	char	*MR_trace_get_command(const char *prompt, FILE *mdb_in,
+				FILE *mdb_out);
 
 #endif	/* MERCURY_TRACE_INTERNAL_H */

util/mkinit.c

@@ -186,6 +186,7 @@ static const char mercury_funcs[] =
 	"	MR_trace_func_ptr = MR_trace_real;\n"
 	"	MR_register_module_layout = MR_register_module_layout_real;\n"
 	"	MR_address_of_trace_getline = MR_trace_getline;\n"
+	"	MR_address_of_trace_get_command = MR_trace_get_command;\n"
 	"	MR_address_of_trace_interrupt_handler =\n"
 	"		MR_trace_interrupt_handler;\n"
 	"  #ifdef MR_USE_EXTERNAL_DEBUGGER\n"
@@ -196,6 +197,7 @@ static const char mercury_funcs[] =
 	"	MR_trace_func_ptr = MR_trace_fake;\n"
 	"	MR_register_module_layout = NULL;\n"
 	"	MR_address_of_trace_getline = NULL;\n"
+	"	MR_address_of_trace_get_command = NULL;\n"
 	"	MR_address_of_trace_interrupt_handler = NULL;\n"
 	"  #ifdef MR_USE_EXTERNAL_DEBUGGER\n"
 	"	MR_address_of_trace_init_external = NULL;\n"