[PATCH] gdb: multi-line support for "document" command

Rae Kim via Gdb-patches
2020-11-28T14:36:09Z

"document" command executed in python, gdb.execute("document
<comname>\n...\nend\n"), will wait for user input. Python extension stops
working from that point.

"define" command works well with gdb.execute(). Looks like, when multi-line
support was first introdued in commit 56bcdbea2b, "document" was left out.

I checked the way "define" handles multi-line mode. And applied it to
"document" command.

gdb/ChangeLog:
2020-11-28 Rae Kim <rae.kim@gmail.com>

* gdb/cli/cli-script.c (do_document_command): Renamed from
* document_command() and handles multi-line input
(multi_line_command_p): Handles document_control.
(build_command_line): Likewise.
(execute_control_command_1): Likewise.
(process_next_line): Likewise.
(document_command): Calls do_document_command with.
* gdb/cli/cli-script.h (enum command_control_type): Added
document_control.
---
gdb/cli/cli-script.c | 42 ++++++++++++++++++++++++++++++++++++++----
gdb/cli/cli-script.h | 1 +
2 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c
index afa44af95a..25807080e5 100644
--- a/gdb/cli/cli-script.c
+++ b/gdb/cli/cli-script.c
@@ -51,6 +51,9 @@ recurse_read_control_structure
static void do_define_command (const char *comname, int from_tty,
const counted_command_line *commands);

+static void do_document_command (const char *comname, int from_tty,
+ const counted_command_line *commands);
+
static const char *read_next_line ();

/* Level of control structure when reading. */
@@ -71,6 +74,9 @@ static cmd_list_element *if_cmd_element = nullptr;
/* Command element for the 'define' command. */
static cmd_list_element *define_cmd_element = nullptr;

+/* Command element for the 'document' command. */
+static cmd_list_element *document_cmd_element = nullptr;
+
/* Structure for arguments to user defined functions. */

class user_args
@@ -139,6 +145,7 @@ multi_line_command_p (enum command_control_type type)
case python_control:
case guile_control:
case define_control:
+ case document_control:
return 1;
default:
return 0;
@@ -159,6 +166,8 @@ build_command_line (enum command_control_type type, const char *args)
error (_("while command requires an argument."));
else if (type == define_control)
error (_("define command requires an argument."));
+ else if (type == document_control)
+ error (_("document command requires an argument."));
}
gdb_assert (args != NULL);

@@ -679,6 +688,12 @@ execute_control_command_1 (struct command_line *cmd, int from_tty)
ret = simple_control;
break;

+ case document_control:
+ print_command_trace ("document %s", cmd->line);
+ do_document_command (cmd->line, 0, &cmd->body_list_0);
+ ret = simple_control;
+ break;
+
case python_control:
case guile_control:
{
@@ -1019,6 +1034,8 @@ process_next_line (const char *p, struct command_line **command,
*command = build_command_line (commands_control, line_first_arg (p));
else if (cmd == define_cmd_element)
*command = build_command_line (define_control, line_first_arg (p));
+ else if (cmd == document_cmd_element)
+ *command = build_command_line (document_control, line_first_arg (p));
else if (cmd == python_cmd_element && !inline_cmd)
{
/* Note that we ignore the inline "python command" form
@@ -1508,8 +1525,13 @@ define_command (const char *comname, int from_tty)
do_define_command (comname, from_tty, nullptr);
}

+/* Document a user-defined command. If COMMANDS is NULL, then this is a
+ top-level call and the document will be read using read_command_lines.
+ Otherwise, it is a "document" command in an existing command and the
+ commands are provided. */
static void
-document_command (const char *comname, int from_tty)
+do_document_command (const char *comname, int from_tty,
+ const counted_command_line *commands)
{
struct cmd_list_element *c, **list;
const char *tem;
@@ -1526,8 +1548,14 @@ document_command (const char *comname, int from_tty)

std::string prompt = string_printf ("Type documentation for \"%s\".",
comfull);
- counted_command_line doclines = read_command_lines (prompt.c_str (),
+
+ counted_command_line doclines;
+
+ if (commands == nullptr)
+ doclines = read_command_lines (prompt.c_str (),
from_tty, 0, 0);
+ else
+ doclines = *commands;

xfree ((char *) c->doc);

@@ -1553,6 +1581,12 @@ document_command (const char *comname, int from_tty)
}
}

+static void
+document_command (const char *comname, int from_tty)
+{
+ do_document_command (comname, from_tty, nullptr);
+}
+
/* Implementation of the "define-prefix" command. */

static void
@@ -1676,11 +1710,11 @@ _initialize_cli_script ()
/* "document", "define" and "define-prefix" use command_completer,
as this helps the user to either type the command name and/or
its prefixes. */
- c = add_com ("document", class_support, document_command, _("\
+ document_cmd_element = add_com ("document", class_support, document_command, _("\
Document a user-defined command.\n\
Give command name as argument. Give documentation on following lines.\n\
End with a line of just \"end\"."));
- set_cmd_completer (c, command_completer);
+ set_cmd_completer (document_cmd_element, command_completer);
define_cmd_element = add_com ("define", class_support, define_command, _("\
Define a new command name. Command name is argument.\n\
Definition appears on following lines, one command per line.\n\
diff --git a/gdb/cli/cli-script.h b/gdb/cli/cli-script.h
index fcae9abaa9..6ad6e61fb4 100644
--- a/gdb/cli/cli-script.h
+++ b/gdb/cli/cli-script.h
@@ -45,6 +45,7 @@ enum command_control_type
guile_control,
while_stepping_control,
define_control,
+ document_control,
invalid_control
};

--
2.28.0