/* Interface between gdb and its extension languages.
Copyright (C) 2014-2018 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Note: With few exceptions, external functions and variables in this file
have "ext_lang" in the name, and no other symbol in gdb does. */
#include "defs.h"
#include <signal.h>
#include "target.h"
#include "auto-load.h"
#include "breakpoint.h"
#include "event-top.h"
#include "extension.h"
#include "extension-priv.h"
#include "observable.h"
#include "cli/cli-script.h"
#include "python/python.h"
#include "guile/guile.h"
/* Iterate over all external extension languages, regardless of whether the
support has been compiled in or not.
This does not include GDB's own scripting language. */
#define ALL_EXTENSION_LANGUAGES(i, extlang) \
for (/*int*/ i = 0, extlang = extension_languages[0]; \
extlang != NULL; \
extlang = extension_languages[++i])
/* Iterate over all external extension languages that are supported.
This does not include GDB's own scripting language. */
#define ALL_ENABLED_EXTENSION_LANGUAGES(i, extlang) \
for (/*int*/ i = 0, extlang = extension_languages[0]; \
extlang != NULL; \
extlang = extension_languages[++i]) \
if (extlang->ops != NULL)
static script_sourcer_func source_gdb_script;
static objfile_script_sourcer_func source_gdb_objfile_script;
/* GDB's own scripting language.
This exists, in part, to support auto-loading ${prog}-gdb.gdb scripts. */
static const struct extension_language_script_ops
extension_language_gdb_script_ops =
{
source_gdb_script,
source_gdb_objfile_script,
NULL, /* objfile_script_executor */
auto_load_gdb_scripts_enabled
};
const struct extension_language_defn extension_language_gdb =
{
EXT_LANG_GDB,
"gdb",
"GDB",
/* We fall back to interpreting a script as a GDB script if it doesn't
match the other scripting languages, but for consistency's sake
give it a formal suffix. */
".gdb",
"-gdb.gdb",
/* cli_control_type: This is never used: GDB's own scripting language
has a variety of control types (if, while, etc.). */
commands_control,
&extension_language_gdb_script_ops,
/* The rest of the extension language interface isn't supported by GDB's own
extension/scripting language. */
NULL
};
/* NULL-terminated table of all external (non-native) extension languages.
The order of appearance in the table is important.
When multiple extension languages provide the same feature, for example
a pretty-printer for a particular type, which one gets used?
The algorithm employed here is "the first one wins". For example, in
the case of pretty-printers this means the first one to provide a
pretty-printed value is the one that is used. This algorithm is employed
throughout. */
static const struct extension_language_defn * const extension_languages[] =
{
/* To preserve existing behaviour, python should always appear first. */
&extension_language_python,
&extension_language_guile,
NULL
};
/* Return a pointer to the struct extension_language_defn object of
extension language LANG.
This always returns a non-NULL pointer, even if support for the language
is not compiled into this copy of GDB. */
const struct extension_language_defn *
get_ext_lang_defn (enum extension_language lang)
{
int i;
const struct extension_language_defn *extlang;
gdb_assert (lang != EXT_LANG_NONE);
if (lang == EXT_LANG_GDB)
return &extension_language_gdb;
ALL_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->language == lang)
return extlang;
}
gdb_assert_not_reached ("unable to find extension_language_defn");
}
/* Return TRUE if FILE has extension EXTENSION. */
static int
has_extension (const char *file, const char *extension)
{
int file_len = strlen (file);
int extension_len = strlen (extension);
return (file_len > extension_len
&& strcmp (&file[file_len - extension_len], extension) == 0);
}
/* Return the extension language of FILE, or NULL if
the extension language of FILE is not recognized.
This is done by looking at the file's suffix. */
const struct extension_language_defn *
get_ext_lang_of_file (const char *file)
{
int i;
const struct extension_language_defn *extlang;
ALL_EXTENSION_LANGUAGES (i, extlang)
{
if (has_extension (file, extlang->suffix))
return extlang;
}
return NULL;
}
/* Return non-zero if support for the specified extension language
is compiled in. */
int
ext_lang_present_p (const struct extension_language_defn *extlang)
{
return extlang->script_ops != NULL;
}
/* Return non-zero if the specified extension language has successfully
initialized. */
int
ext_lang_initialized_p (const struct extension_language_defn *extlang)
{
if (extlang->ops != NULL)
{
/* This method is required. */
gdb_assert (extlang->ops->initialized != NULL);
return extlang->ops->initialized (extlang);
}
return 0;
}
/* Throw an error indicating EXTLANG is not supported in this copy of GDB. */
void
throw_ext_lang_unsupported (const struct extension_language_defn *extlang)
{
error (_("Scripting in the \"%s\" language is not supported"
" in this copy of GDB."),
ext_lang_capitalized_name (extlang));
}
/* Methods for GDB's own extension/scripting language. */
/* The extension_language_script_ops.script_sourcer "method". */
static void
source_gdb_script (const struct extension_language_defn *extlang,
FILE *stream, const char *file)
{
script_from_file (stream, file);
}
/* The extension_language_script_ops.objfile_script_sourcer "method". */
static void
source_gdb_objfile_script (const struct extension_language_defn *extlang,
struct objfile *objfile,
FILE *stream, const char *file)
{
script_from_file (stream, file);
}
/* Accessors for "public" attributes of struct extension_language. */
/* Return the "name" field of EXTLANG. */
const char *
ext_lang_name (const struct extension_language_defn *extlang)
{
return extlang->name;
}
/* Return the "capitalized_name" field of EXTLANG. */
const char *
ext_lang_capitalized_name (const struct extension_language_defn *extlang)
{
return extlang->capitalized_name;
}
/* Return the "suffix" field of EXTLANG. */
const char *
ext_lang_suffix (const struct extension_language_defn *extlang)
{
return extlang->suffix;
}
/* Return the "auto_load_suffix" field of EXTLANG. */
const char *
ext_lang_auto_load_suffix (const struct extension_language_defn *extlang)
{
return extlang->auto_load_suffix;
}
/* extension_language_script_ops wrappers. */
/* Return the script "sourcer" function for EXTLANG.
This is the function that loads and processes a script.
If support for this language isn't compiled in, NULL is returned. */
script_sourcer_func *
ext_lang_script_sourcer (const struct extension_language_defn *extlang)
{
if (extlang->script_ops == NULL)
return NULL;
/* The extension language is required to implement this function. */
gdb_assert (extlang->script_ops->script_sourcer != NULL);
return extlang->script_ops->script_sourcer;
}
/* Return the objfile script "sourcer" function for EXTLANG.
This is the function that loads and processes a script for a particular
objfile.
If support for this language isn't compiled in, NULL is returned. */
objfile_script_sourcer_func *
ext_lang_objfile_script_sourcer (const struct extension_language_defn *extlang)
{
if (extlang->script_ops == NULL)
return NULL;
/* The extension language is required to implement this function. */
gdb_assert (extlang->script_ops->objfile_script_sourcer != NULL);
return extlang->script_ops->objfile_script_sourcer;
}
/* Return the objfile script "executor" function for EXTLANG.
This is the function that executes a script for a particular objfile.
If support for this language isn't compiled in, NULL is returned.
The extension language is not required to implement this function. */
objfile_script_executor_func *
ext_lang_objfile_script_executor
(const struct extension_language_defn *extlang)
{
if (extlang->script_ops == NULL)
return NULL;
return extlang->script_ops->objfile_script_executor;
}
/* Return non-zero if auto-loading of EXTLANG scripts is enabled.
Zero is returned if support for this language isn't compiled in. */
int
ext_lang_auto_load_enabled (const struct extension_language_defn *extlang)
{
if (extlang->script_ops == NULL)
return 0;
/* The extension language is required to implement this function. */
gdb_assert (extlang->script_ops->auto_load_enabled != NULL);
return extlang->script_ops->auto_load_enabled (extlang);
}
/* Functions that iterate over all extension languages.
These only iterate over external extension languages, not including
GDB's own extension/scripting language, unless otherwise indicated. */
/* Wrapper to call the extension_language_ops.finish_initialization "method"
for each compiled-in extension language. */
void
finish_ext_lang_initialization (void)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->ops->finish_initialization != NULL)
extlang->ops->finish_initialization (extlang);
}
}
/* Invoke the appropriate extension_language_ops.eval_from_control_command
method to perform CMD, which is a list of commands in an extension language.
This function is what implements, for example:
python
print 42
end
in a GDB script. */
void
eval_ext_lang_from_control_command (struct command_line *cmd)
{
int i;
const struct extension_language_defn *extlang;
ALL_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->cli_control_type == cmd->control_type)
{
if (extlang->ops != NULL
&& extlang->ops->eval_from_control_command != NULL)
{
extlang->ops->eval_from_control_command (extlang, cmd);
return;
}
/* The requested extension language is not supported in this GDB. */
throw_ext_lang_unsupported (extlang);
}
}
gdb_assert_not_reached ("unknown extension language in command_line");
}
/* Search for and load scripts for OBJFILE written in extension languages.
This includes GDB's own scripting language.
This function is what implements the loading of OBJFILE-gdb.py and
OBJFILE-gdb.gdb. */
void
auto_load_ext_lang_scripts_for_objfile (struct objfile *objfile)
{
int i;
const struct extension_language_defn *extlang;
extlang = &extension_language_gdb;
if (ext_lang_auto_load_enabled (extlang))
auto_load_objfile_script (objfile, extlang);
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (ext_lang_auto_load_enabled (extlang))
auto_load_objfile_script (objfile, extlang);
}
}
/* Interface to type pretty-printers implemented in an extension language. */
/* Call this at the start when preparing to pretty-print a type.
The result is a pointer to an opaque object (to the caller) to be passed
to apply_ext_lang_type_printers and free_ext_lang_type_printers.
We don't know in advance which extension language will provide a
pretty-printer for the type, so all are initialized. */
ext_lang_type_printers::ext_lang_type_printers ()
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->ops->start_type_printers != NULL)
extlang->ops->start_type_printers (extlang, this);
}
}
/* Iteratively try the type pretty-printers specified by PRINTERS
according to the standard search order (specified by extension_languages),
returning the result of the first one that succeeds.
If there was an error, or if no printer succeeds, then NULL is returned. */
char *
apply_ext_lang_type_printers (struct ext_lang_type_printers *printers,
struct type *type)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
char *result = NULL;
enum ext_lang_rc rc;
if (extlang->ops->apply_type_printers == NULL)
continue;
rc = extlang->ops->apply_type_printers (extlang, printers, type,
&result);
switch (rc)
{
case EXT_LANG_RC_OK:
gdb_assert (result != NULL);
return result;
case EXT_LANG_RC_ERROR:
return NULL;
case EXT_LANG_RC_NOP:
break;
default:
gdb_assert_not_reached ("bad return from apply_type_printers");
}
}
return NULL;
}
ext_lang_type_printers::~ext_lang_type_printers ()
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->ops->free_type_printers != NULL)
extlang->ops->free_type_printers (extlang, this);
}
}
/* Try to pretty-print a value of type TYPE located at VAL's contents
buffer + EMBEDDED_OFFSET, which came from the inferior at address
ADDRESS + EMBEDDED_OFFSET, onto stdio stream STREAM according to
OPTIONS.
VAL is the whole object that came from ADDRESS.
Returns non-zero if the value was successfully pretty-printed.
Extension languages are tried in the order specified by
extension_languages. The first one to provide a pretty-printed
value "wins".
If an error is encountered in a pretty-printer, no further extension
languages are tried.
Note: This is different than encountering a memory error trying to read a
value for pretty-printing. Here we're referring to, e.g., programming
errors that trigger an exception in the extension language. */
int
apply_ext_lang_val_pretty_printer (struct type *type,
LONGEST embedded_offset, CORE_ADDR address,
struct ui_file *stream, int recurse,
struct value *val,
const struct value_print_options *options,
const struct language_defn *language)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
enum ext_lang_rc rc;
if (extlang->ops->apply_val_pretty_printer == NULL)
continue;
rc = extlang->ops->apply_val_pretty_printer (extlang, type,
embedded_offset, address,
stream, recurse, val,
options, language);
switch (rc)
{
case EXT_LANG_RC_OK:
return 1;
case EXT_LANG_RC_ERROR:
return 0;
case EXT_LANG_RC_NOP:
break;
default:
gdb_assert_not_reached ("bad return from apply_val_pretty_printer");
}
}
return 0;
}
/* GDB access to the "frame filter" feature.
FRAME is the source frame to start frame-filter invocation. FLAGS is an
integer holding the flags for printing. The following elements of
the FRAME_FILTER_FLAGS enum denotes the make-up of FLAGS:
PRINT_LEVEL is a flag indicating whether to print the frame's
relative level in the output. PRINT_FRAME_INFO is a flag that
indicates whether this function should print the frame
information, PRINT_ARGS is a flag that indicates whether to print
frame arguments, and PRINT_LOCALS, likewise, with frame local
variables. ARGS_TYPE is an enumerator describing the argument
format, OUT is the output stream to print. FRAME_LOW is the
beginning of the slice of frames to print, and FRAME_HIGH is the
upper limit of the frames to count. Returns EXT_LANG_BT_ERROR on error,
or EXT_LANG_BT_COMPLETED on success.
Extension languages are tried in the order specified by
extension_languages. The first one to provide a filter "wins".
If there is an error (EXT_LANG_BT_ERROR) it is reported immediately
rather than trying filters in other extension languages. */
enum ext_lang_bt_status
apply_ext_lang_frame_filter (struct frame_info *frame,
frame_filter_flags flags,
enum ext_lang_frame_args args_type,
struct ui_out *out,
int frame_low, int frame_high)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
enum ext_lang_bt_status status;
if (extlang->ops->apply_frame_filter == NULL)
continue;
status = extlang->ops->apply_frame_filter (extlang, frame, flags,
args_type, out,
frame_low, frame_high);
/* We use the filters from the first extension language that has
applicable filters. Also, an error is reported immediately
rather than continue trying. */
if (status != EXT_LANG_BT_NO_FILTERS)
return status;
}
return EXT_LANG_BT_NO_FILTERS;
}
/* Update values held by the extension language when OBJFILE is discarded.
New global types must be created for every such value, which must then be
updated to use the new types.
The function typically just iterates over all appropriate values and
calls preserve_one_value for each one.
COPIED_TYPES is used to prevent cycles / duplicates and is passed to
preserve_one_value. */
void
preserve_ext_lang_values (struct objfile *objfile, htab_t copied_types)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->ops->preserve_values != NULL)
extlang->ops->preserve_values (extlang, objfile, copied_types);
}
}
/* If there is a stop condition implemented in an extension language for
breakpoint B, return a pointer to the extension language's definition.
Otherwise return NULL.
If SKIP_LANG is not EXT_LANG_NONE, skip checking this language.
This is for the case where we're setting a new condition: Only one
condition is allowed, so when setting a condition for any particular
extension language, we need to check if any other extension language
already has a condition set. */
const struct extension_language_defn *
get_breakpoint_cond_ext_lang (struct breakpoint *b,
enum extension_language skip_lang)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->language != skip_lang
&& extlang->ops->breakpoint_has_cond != NULL
&& extlang->ops->breakpoint_has_cond (extlang, b))
return extlang;
}
return NULL;
}
/* Return whether a stop condition for breakpoint B says to stop.
True is also returned if there is no stop condition for B. */
int
breakpoint_ext_lang_cond_says_stop (struct breakpoint *b)
{
int i;
const struct extension_language_defn *extlang;
enum ext_lang_bp_stop stop = EXT_LANG_BP_STOP_UNSET;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
/* There is a rule that a breakpoint can have at most one of any of a
CLI or extension language condition. However, Python hacks in "finish
breakpoints" on top of the "stop" check, so we have to call this for
every language, even if we could first determine whether a "stop"
method exists. */
if (extlang->ops->breakpoint_cond_says_stop != NULL)
{
enum ext_lang_bp_stop this_stop
= extlang->ops->breakpoint_cond_says_stop (extlang, b);
if (this_stop != EXT_LANG_BP_STOP_UNSET)
{
/* Even though we have to check every extension language, only
one of them can return yes/no (because only one of them
can have a "stop" condition). */
gdb_assert (stop == EXT_LANG_BP_STOP_UNSET);
stop = this_stop;
}
}
}
return stop == EXT_LANG_BP_STOP_NO ? 0 : 1;
}
/* ^C/SIGINT support.
This requires cooperation with the extension languages so the support
is defined here. */
/* This flag tracks quit requests when we haven't called out to an
extension language. it also holds quit requests when we transition to
an extension language that doesn't have cooperative SIGINT handling. */
static int quit_flag;
/* The current extension language we've called out to, or
extension_language_gdb if there isn't one.
This must be set everytime we call out to an extension language, and reset
to the previous value when it returns. Note that the previous value may
be a different (or the same) extension language. */
static const struct extension_language_defn *active_ext_lang
= &extension_language_gdb;
/* Return the currently active extension language. */
const struct extension_language_defn *
get_active_ext_lang (void)
{
return active_ext_lang;
}
/* Install a SIGINT handler. */
static void
install_sigint_handler (const struct signal_handler *handler_state)
{
gdb_assert (handler_state->handler_saved);
signal (SIGINT, handler_state->handler);
}
/* Install GDB's SIGINT handler, storing the previous version in *PREVIOUS.
As a simple optimization, if the previous version was GDB's SIGINT handler
then mark the previous handler as not having been saved, and thus it won't
be restored. */
static void
install_gdb_sigint_handler (struct signal_handler *previous)
{
/* Save here to simplify comparison. */
sighandler_t handle_sigint_for_compare = handle_sigint;
previous->handler = signal (SIGINT, handle_sigint);
if (previous->handler != handle_sigint_for_compare)
previous->handler_saved = 1;
else
previous->handler_saved = 0;
}
/* Set the currently active extension language to NOW_ACTIVE.
The result is a pointer to a malloc'd block of memory to pass to
restore_active_ext_lang.
N.B. This function must be called every time we call out to an extension
language, and the result must be passed to restore_active_ext_lang
afterwards.
If there is a pending SIGINT it is "moved" to the now active extension
language, if it supports cooperative SIGINT handling (i.e., it provides
{clear,set,check}_quit_flag methods). If the extension language does not
support cooperative SIGINT handling, then the SIGINT is left queued and
we require the non-cooperative extension language to call check_quit_flag
at appropriate times.
It is important for the extension language to call check_quit_flag if it
installs its own SIGINT handler to prevent the situation where a SIGINT
is queued on entry, extension language code runs for a "long" time possibly
serving one or more SIGINTs, and then returns. Upon return, if
check_quit_flag is not called, the original SIGINT will be thrown.
Non-cooperative extension languages are free to install their own SIGINT
handler but the original must be restored upon return, either itself
or via restore_active_ext_lang. */
struct active_ext_lang_state *
set_active_ext_lang (const struct extension_language_defn *now_active)
{
struct active_ext_lang_state *previous
= XCNEW (struct active_ext_lang_state);
previous->ext_lang = active_ext_lang;
previous->sigint_handler.handler_saved = 0;
active_ext_lang = now_active;
if (target_terminal::is_ours ())
{
/* If the newly active extension language uses cooperative SIGINT
handling then ensure GDB's SIGINT handler is installed. */
if (now_active->language == EXT_LANG_GDB
|| now_active->ops->check_quit_flag != NULL)
install_gdb_sigint_handler (&previous->sigint_handler);
/* If there's a SIGINT recorded in the cooperative extension languages,
move it to the new language, or save it in GDB's global flag if the
newly active extension language doesn't use cooperative SIGINT
handling. */
if (check_quit_flag ())
set_quit_flag ();
}
return previous;
}
/* Restore active extension language from PREVIOUS. */
void
restore_active_ext_lang (struct active_ext_lang_state *previous)
{
active_ext_lang = previous->ext_lang;
if (target_terminal::is_ours ())
{
/* Restore the previous SIGINT handler if one was saved. */
if (previous->sigint_handler.handler_saved)
install_sigint_handler (&previous->sigint_handler);
/* If there's a SIGINT recorded in the cooperative extension languages,
move it to the new language, or save it in GDB's global flag if the
newly active extension language doesn't use cooperative SIGINT
handling. */
if (check_quit_flag ())
set_quit_flag ();
}
xfree (previous);
}
/* Set the quit flag.
This only sets the flag in the currently active extension language.
If the currently active extension language does not have cooperative
SIGINT handling, then GDB's global flag is set, and it is up to the
extension language to call check_quit_flag. The extension language
is free to install its own SIGINT handler, but we still need to handle
the transition. */
void
set_quit_flag (void)
{
if (active_ext_lang->ops != NULL
&& active_ext_lang->ops->set_quit_flag != NULL)
active_ext_lang->ops->set_quit_flag (active_ext_lang);
else
{
quit_flag = 1;
/* Now wake up the event loop, or any interruptible_select. Do
this after setting the flag, because signals on Windows
actually run on a separate thread, and thus otherwise the
main code could be woken up and find quit_flag still
clear. */
quit_serial_event_set ();
}
}
/* Return true if the quit flag has been set, false otherwise.
Note: The flag is cleared as a side-effect.
The flag is checked in all extension languages that support cooperative
SIGINT handling, not just the current one. This simplifies transitions. */
int
check_quit_flag (void)
{
int i, result = 0;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
if (extlang->ops->check_quit_flag != NULL)
if (extlang->ops->check_quit_flag (extlang) != 0)
result = 1;
}
/* This is written in a particular way to avoid races. */
if (quit_flag)
{
/* No longer need to wake up the event loop or any
interruptible_select. The caller handles the quit
request. */
quit_serial_event_clear ();
quit_flag = 0;
result = 1;
}
return result;
}
/* See extension.h. */
void
get_matching_xmethod_workers (struct type *type, const char *method_name,
std::vector<xmethod_worker_up> *workers)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
enum ext_lang_rc rc;
/* If an extension language does not support xmethods, ignore
it. */
if (extlang->ops->get_matching_xmethod_workers == NULL)
continue;
rc = extlang->ops->get_matching_xmethod_workers (extlang,
type, method_name,
workers);
if (rc == EXT_LANG_RC_ERROR)
error (_("Error while looking for matching xmethod workers "
"defined in %s."), extlang->capitalized_name);
}
}
/* See extension.h. */
type **
xmethod_worker::get_arg_types (int *nargs)
{
type **type_array = NULL;
ext_lang_rc rc = do_get_arg_types (nargs, &type_array);
if (rc == EXT_LANG_RC_ERROR)
error (_("Error while looking for arg types of a xmethod worker "
"defined in %s."), m_extlang->capitalized_name);
return type_array;
}
/* See extension.h. */
struct type *
xmethod_worker::get_result_type (value *object, value **args, int nargs)
{
type *result_type;
ext_lang_rc rc = do_get_result_type (object, args, nargs, &result_type);
if (rc == EXT_LANG_RC_ERROR)
{
error (_("Error while fetching result type of an xmethod worker "
"defined in %s."), m_extlang->capitalized_name);
}
return result_type;
}
/* Called via an observer before gdb prints its prompt.
Iterate over the extension languages giving them a chance to
change the prompt. The first one to change the prompt wins,
and no further languages are tried. */
static void
ext_lang_before_prompt (const char *current_gdb_prompt)
{
int i;
const struct extension_language_defn *extlang;
ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang)
{
enum ext_lang_rc rc;
if (extlang->ops->before_prompt == NULL)
continue;
rc = extlang->ops->before_prompt (extlang, current_gdb_prompt);
switch (rc)
{
case EXT_LANG_RC_OK:
case EXT_LANG_RC_ERROR:
return;
case EXT_LANG_RC_NOP:
break;
default:
gdb_assert_not_reached ("bad return from before_prompt");
}
}
}
void
_initialize_extension (void)
{
gdb::observers::before_prompt.attach (ext_lang_before_prompt);
}