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/*
signals.c : irssi
Copyright (C) 1999-2002 Timo Sirainen
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 2 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, write to the Free Software
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "module.h"
#include "signals.h"
#include "modules.h"
typedef struct _SignalHook {
struct _SignalHook *next;
int priority;
const char *module;
SIGNAL_FUNC func;
void *user_data;
} SignalHook;
typedef struct {
int id; /* signal id */
int refcount;
int emitting; /* signal is being emitted */
int stop_emit; /* this signal was stopped */
int continue_emit; /* this signal emit was continued elsewhere */
int remove_count; /* hooks were removed from signal */
SignalHook *hooks;
} Signal;
void *signal_user_data;
static GHashTable *signals;
static Signal *current_emitted_signal;
static SignalHook *current_emitted_hook;
#define signal_ref(signal) ++(signal)->refcount
#define signal_unref(signal) (signal_unref_full(signal, TRUE))
static int signal_unref_full(Signal *rec, int remove)
{
g_assert(rec->refcount > 0);
if (--rec->refcount != 0)
return TRUE;
/* remove whole signal from memory */
if (rec->hooks != NULL) {
g_error("signal_unref(%s) : BUG - hook list wasn't empty",
signal_get_id_str(rec->id));
}
if (remove)
g_hash_table_remove(signals, GINT_TO_POINTER(rec->id));
g_free(rec);
return FALSE;
}
static void signal_hash_ref(void *key, Signal *rec)
{
signal_ref(rec);
}
static int signal_hash_unref(void *key, Signal *rec)
{
return !signal_unref_full(rec, FALSE);
}
void signal_add_full(const char *module, int priority,
const char *signal, SIGNAL_FUNC func, void *user_data)
{
signal_add_full_id(module, priority, signal_get_uniq_id(signal),
func, user_data);
}
/* bind a signal */
void signal_add_full_id(const char *module, int priority,
int signal_id, SIGNAL_FUNC func, void *user_data)
{
Signal *signal;
SignalHook *hook, **tmp;
g_return_if_fail(signal_id >= 0);
g_return_if_fail(func != NULL);
signal = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
if (signal == NULL) {
/* new signal */
signal = g_new0(Signal, 1);
signal->id = signal_id;
g_hash_table_insert(signals, GINT_TO_POINTER(signal_id), signal);
}
hook = g_new0(SignalHook, 1);
hook->priority = priority;
hook->module = module;
hook->func = func;
hook->user_data = user_data;
/* insert signal to proper position in list */
for (tmp = &signal->hooks; ; tmp = &(*tmp)->next) {
if (*tmp == NULL) {
/* last in list */
*tmp = hook;
break;
} else if (priority <= (*tmp)->priority) {
/* insert before others with same priority */
hook->next = *tmp;
*tmp = hook;
break;
}
}
signal_ref(signal);
}
static void signal_remove_hook(Signal *rec, SignalHook **hook_pos)
{
SignalHook *hook;
hook = *hook_pos;
*hook_pos = hook->next;
g_free(hook);
signal_unref(rec);
}
/* Remove function from signal's emit list */
static int signal_remove_func(Signal *rec, SIGNAL_FUNC func, void *user_data)
{
SignalHook **hook;
for (hook = &rec->hooks; *hook != NULL; hook = &(*hook)->next) {
if ((*hook)->func == func && (*hook)->user_data == user_data) {
if (rec->emitting) {
/* mark it removed after emitting is done */
(*hook)->func = NULL;
rec->remove_count++;
} else {
/* remove the function from emit list */
signal_remove_hook(rec, hook);
}
return TRUE;
}
}
return FALSE;
}
void signal_remove_id(int signal_id, SIGNAL_FUNC func, void *user_data)
{
Signal *rec;
g_return_if_fail(signal_id >= 0);
g_return_if_fail(func != NULL);
rec = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
if (rec != NULL)
signal_remove_func(rec, func, user_data);
}
/* unbind signal */
void signal_remove_full(const char *signal, SIGNAL_FUNC func, void *user_data)
{
g_return_if_fail(signal != NULL);
signal_remove_id(signal_get_uniq_id(signal), func, user_data);
}
static void signal_hooks_clean(Signal *rec)
{
SignalHook **hook, **next;
int count;
count = rec->remove_count;
rec->remove_count = 0;
for (hook = &rec->hooks; *hook != NULL; hook = next) {
next = &(*hook)->next;
if ((*hook)->func == NULL) {
next = hook;
signal_remove_hook(rec, hook);
if (--count == 0)
break;
}
}
}
static int signal_emit_real(Signal *rec, int params, va_list va,
SignalHook *first_hook)
{
const void *arglist[SIGNAL_MAX_ARGUMENTS];
Signal *prev_emitted_signal;
SignalHook *hook, *prev_emitted_hook;
int i, stopped, stop_emit_count, continue_emit_count;
for (i = 0; i < SIGNAL_MAX_ARGUMENTS; i++)
arglist[i] = i >= params ? NULL : va_arg(va, const void *);
/* signal_stop_by_name("signal"); signal_emit("signal", ...);
fails if we compare rec->stop_emit against 0. */
stop_emit_count = rec->stop_emit;
continue_emit_count = rec->continue_emit;
signal_ref(rec);
stopped = FALSE;
rec->emitting++;
prev_emitted_signal = current_emitted_signal;
prev_emitted_hook = current_emitted_hook;
current_emitted_signal = rec;
for (hook = first_hook; hook != NULL; hook = hook->next) {
if (hook->func == NULL)
continue; /* removed */
current_emitted_hook = hook;
#if SIGNAL_MAX_ARGUMENTS != 6
# error SIGNAL_MAX_ARGUMENTS changed - update code
#endif
signal_user_data = hook->user_data;
hook->func(arglist[0], arglist[1], arglist[2], arglist[3],
arglist[4], arglist[5]);
if (rec->continue_emit != continue_emit_count)
rec->continue_emit--;
if (rec->stop_emit != stop_emit_count) {
stopped = TRUE;
rec->stop_emit--;
break;
}
}
current_emitted_signal = prev_emitted_signal;
current_emitted_hook = prev_emitted_hook;
rec->emitting--;
signal_user_data = NULL;
if (!rec->emitting) {
g_assert(rec->stop_emit == 0);
g_assert(rec->continue_emit == 0);
if (rec->remove_count > 0)
signal_hooks_clean(rec);
}
signal_unref(rec);
return stopped;
}
int signal_emit(const char *signal, int params, ...)
{
Signal *rec;
va_list va;
int signal_id;
g_return_val_if_fail(params >= 0 && params <= SIGNAL_MAX_ARGUMENTS, FALSE);
signal_id = signal_get_uniq_id(signal);
rec = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
if (rec != NULL) {
va_start(va, params);
signal_emit_real(rec, params, va, rec->hooks);
va_end(va);
}
return rec != NULL;
}
int signal_emit_id(int signal_id, int params, ...)
{
Signal *rec;
va_list va;
g_return_val_if_fail(signal_id >= 0, FALSE);
g_return_val_if_fail(params >= 0 && params <= SIGNAL_MAX_ARGUMENTS, FALSE);
rec = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
if (rec != NULL) {
va_start(va, params);
signal_emit_real(rec, params, va, rec->hooks);
va_end(va);
}
return rec != NULL;
}
void signal_continue(int params, ...)
{
Signal *rec;
va_list va;
rec = current_emitted_signal;
if (rec == NULL || rec->emitting <= rec->continue_emit)
g_warning("signal_continue() : no signals are being emitted currently");
else {
va_start(va, params);
/* stop the signal */
if (rec->emitting > rec->stop_emit)
rec->stop_emit++;
/* re-emit */
rec->continue_emit++;
signal_emit_real(rec, params, va, current_emitted_hook->next);
va_end(va);
}
}
/* stop the current ongoing signal emission */
void signal_stop(void)
{
Signal *rec;
rec = current_emitted_signal;
if (rec == NULL)
g_warning("signal_stop() : no signals are being emitted currently");
else if (rec->emitting > rec->stop_emit)
rec->stop_emit++;
}
/* stop ongoing signal emission by signal name */
void signal_stop_by_name(const char *signal)
{
Signal *rec;
int signal_id;
signal_id = signal_get_uniq_id(signal);
rec = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
if (rec == NULL)
g_warning("signal_stop_by_name() : unknown signal \"%s\"", signal);
else if (rec->emitting > rec->stop_emit)
rec->stop_emit++;
}
/* return the name of the signal that is currently being emitted */
const char *signal_get_emitted(void)
{
return signal_get_id_str(signal_get_emitted_id());
}
/* return the ID of the signal that is currently being emitted */
int signal_get_emitted_id(void)
{
Signal *rec;
rec = current_emitted_signal;
g_return_val_if_fail(rec != NULL, -1);
return rec->id;
}
/* return TRUE if specified signal was stopped */
int signal_is_stopped(int signal_id)
{
Signal *rec;
rec = g_hash_table_lookup(signals, GINT_TO_POINTER(signal_id));
g_return_val_if_fail(rec != NULL, FALSE);
return rec->emitting <= rec->stop_emit;
}
static void signal_remove_module(void *signal, Signal *rec,
const char *module)
{
SignalHook **hook, **next;
for (hook = &rec->hooks; *hook != NULL; hook = next) {
next = &(*hook)->next;
if (strcasecmp((*hook)->module, module) == 0) {
next = hook;
signal_remove_hook(rec, hook);
}
}
}
/* remove all signals that belong to `module' */
void signals_remove_module(const char *module)
{
g_return_if_fail(module != NULL);
g_hash_table_foreach(signals, (GHFunc) signal_hash_ref, NULL);
g_hash_table_foreach(signals, (GHFunc) signal_remove_module,
(void *) module);
g_hash_table_foreach_remove(signals, (GHRFunc) signal_hash_unref, NULL);
}
void signals_init(void)
{
signals = g_hash_table_new(NULL, NULL);
}
static void signal_free(void *key, Signal *rec)
{
/* refcount-1 because we just referenced it ourself */
g_warning("signal_free(%s) : signal still has %d references:",
signal_get_id_str(rec->id), rec->refcount-1);
while (rec->hooks != NULL) {
g_warning(" - module '%s' function %p",
rec->hooks->module, rec->hooks->func);
signal_remove_hook(rec, &rec->hooks);
}
}
void signals_deinit(void)
{
g_hash_table_foreach(signals, (GHFunc) signal_hash_ref, NULL);
g_hash_table_foreach(signals, (GHFunc) signal_free, NULL);
g_hash_table_foreach_remove(signals, (GHRFunc) signal_hash_unref, NULL);
g_hash_table_destroy(signals);
module_uniq_destroy("signals");
}
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