weechat/src/core/hook/hook-signal.c

/*
 * SPDX-FileCopyrightText: 2003-2026 Sébastien Helleu <flashcode@flashtux.org>
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * This file is part of WeeChat, the extensible chat client.
 *
 * WeeChat 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.
 *
 * WeeChat 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 WeeChat.  If not, see <https://www.gnu.org/licenses/>.
 */

/* WeeChat signal hook */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdlib.h>
#include <string.h>

#include "../weechat.h"
#include "../core-hook.h"
#include "../core-hdata.h"
#include "../core-infolist.h"
#include "../core-log.h"
#include "../core-string.h"
#include "../../plugins/plugin.h"


/*
 * Return description of hook.
 *
 * Note: result must be freed after use.
 */

char *
hook_signal_get_description (struct t_hook *hook)
{
    return string_rebuild_split_string (
        (const char **)(HOOK_SIGNAL(hook, signals)), ";", 0, -1);
}

/*
 * Hook a signal.
 *
 * Return pointer to new hook, NULL if error.
 */

struct t_hook *
hook_signal (struct t_weechat_plugin *plugin, const char *signal,
             t_hook_callback_signal *callback,
             const void *callback_pointer,
             void *callback_data)
{
    struct t_hook *new_hook;
    struct t_hook_signal *new_hook_signal;
    int priority;
    const char *ptr_signal;

    if (!signal || !signal[0] || !callback)
        return NULL;

    new_hook = malloc (sizeof (*new_hook));
    if (!new_hook)
        return NULL;
    new_hook_signal = malloc (sizeof (*new_hook_signal));
    if (!new_hook_signal)
    {
        free (new_hook);
        return NULL;
    }

    string_get_priority_and_name (signal, &priority, &ptr_signal,
                                  HOOK_PRIORITY_DEFAULT);
    hook_init_data (new_hook, plugin, HOOK_TYPE_SIGNAL, priority,
                    callback_pointer, callback_data);

    new_hook->hook_data = new_hook_signal;
    new_hook_signal->callback = callback;
    new_hook_signal->signals = string_split (
        (ptr_signal) ? ptr_signal : signal,
        ";",
        NULL,
        WEECHAT_STRING_SPLIT_STRIP_LEFT
        | WEECHAT_STRING_SPLIT_STRIP_RIGHT
        | WEECHAT_STRING_SPLIT_COLLAPSE_SEPS,
        0, &new_hook_signal->num_signals);

    hook_add_to_list (new_hook);

    return new_hook;
}

/*
 * Check if a hooked signal matches a signal sent: it matches if at least
 * one of the signal masks are matching the signal sent.
 *
 * Return:
 *   1: hook matches signal sent
 *   0: hook does not match signal sent
 */

int
hook_signal_match (const char *signal, struct t_hook *hook)
{
    int i;

    for (i = 0; i < HOOK_SIGNAL(hook, num_signals); i++)
    {
        if (string_match (signal, HOOK_SIGNAL(hook, signals)[i], 0))
            return 1;
    }

    return 0;
}

/*
 * Extract flags from signal and return flags and pointer to start of signal.
 */

void
hook_signal_extract_flags (const char *signal, const char **ptr_signal,
                           int *stop_on_error, int *ignore_eat)
{
    char *pos, *str_flags, **flags;
    int i, num_flags;

    if (!signal || !ptr_signal || !stop_on_error || !ignore_eat)
        return;

    *ptr_signal = signal;
    *stop_on_error = 0;
    *ignore_eat = 0;

    if (strncmp (signal, "[flags:", 7) != 0)
        return;

    pos = strchr (signal + 7, ']');
    if (!pos)
        return;

    str_flags = string_strndup (signal + 7, pos - signal - 7);
    if (!str_flags)
        return;

    *ptr_signal = pos + 1;

    flags = string_split (str_flags, ",", NULL,
                          WEECHAT_STRING_SPLIT_STRIP_LEFT
                          | WEECHAT_STRING_SPLIT_STRIP_RIGHT
                          | WEECHAT_STRING_SPLIT_COLLAPSE_SEPS,
                          0, &num_flags);
    if (flags)
    {
        for (i = 0; i < num_flags; i++)
        {
            if (string_strcmp (flags[i], "stop_on_error") == 0)
                *stop_on_error = 1;
            else if (string_strcmp (flags[i], "ignore_eat") == 0)
                *ignore_eat = 1;
        }
    }

    string_free_split (flags);
    free (str_flags);
}

/*
 * Send a signal.
 */

int
hook_signal_send (const char *signal, const char *type_data, void *signal_data)
{
    struct t_hook *ptr_hook, *next_hook;
    struct t_hook_exec_cb hook_exec_cb;
    const char *ptr_signal;
    int rc, stop_on_error, ignore_eat;

    rc = WEECHAT_RC_OK;

    ptr_signal = signal;
    stop_on_error = 0;
    ignore_eat = 0;
    hook_signal_extract_flags (signal, &ptr_signal,
                               &stop_on_error, &ignore_eat);
    if (!ptr_signal)
        return rc;

    hook_exec_start ();

    ptr_hook = weechat_hooks[HOOK_TYPE_SIGNAL];
    while (ptr_hook)
    {
        next_hook = ptr_hook->next_hook;

        if (!ptr_hook->deleted
            && !ptr_hook->running
            && hook_signal_match (ptr_signal, ptr_hook))
        {
            hook_callback_start (ptr_hook, &hook_exec_cb);
            rc = (HOOK_SIGNAL(ptr_hook, callback))
                (ptr_hook->callback_pointer,
                 ptr_hook->callback_data,
                 ptr_signal,
                 type_data,
                 signal_data);
            hook_callback_end (ptr_hook, &hook_exec_cb);

            if (ignore_eat && (rc == WEECHAT_RC_OK_EAT))
                rc = WEECHAT_RC_OK;

            if ((rc == WEECHAT_RC_OK_EAT)
                || (stop_on_error && (rc == WEECHAT_RC_ERROR)))
            {
                break;
            }
        }

        ptr_hook = next_hook;
    }

    hook_exec_end ();

    return rc;
}

/*
 * Free data in a signal hook.
 */

void
hook_signal_free_data (struct t_hook *hook)
{
    if (!hook || !hook->hook_data)
        return;

    if (HOOK_SIGNAL(hook, signals))
    {
        string_free_split (HOOK_SIGNAL(hook, signals));
        HOOK_SIGNAL(hook, signals) = NULL;
    }
    HOOK_SIGNAL(hook, num_signals) = 0;

    free (hook->hook_data);
    hook->hook_data = NULL;
}

/*
 * Return hdata for signal hook.
 */

struct t_hdata *
hook_signal_hdata_hook_signal_cb (const void *pointer, void *data,
                                  const char *hdata_name)
{
    struct t_hdata *hdata;

    /* make C compiler happy */
    (void) pointer;
    (void) data;

    hdata = hdata_new (NULL, hdata_name, NULL, NULL, 0, 0, NULL, NULL);
    if (hdata)
    {
        HDATA_VAR(struct t_hook_signal, callback, POINTER, 0, NULL, NULL);
        HDATA_VAR(struct t_hook_signal, signals, STRING, 0, "*,num_signals", NULL);
        HDATA_VAR(struct t_hook_signal, num_signals, INTEGER, 0, NULL, NULL);
    }
    return hdata;
}

/*
 * Add signal hook data in the infolist item.
 *
 * Return:
 *   1: OK
 *   0: error
 */

int
hook_signal_add_to_infolist (struct t_infolist_item *item,
                              struct t_hook *hook)
{
    int i;
    char option_name[64];

    if (!item || !hook || !hook->hook_data)
        return 0;

    if (!infolist_new_var_pointer (item, "callback", HOOK_SIGNAL(hook, callback)))
        return 0;
    for (i = 0; i < HOOK_SIGNAL(hook, num_signals); i++)
    {
        snprintf (option_name, sizeof (option_name), "signal_%05d", i);
        if (!infolist_new_var_string (item, option_name,
                                      HOOK_SIGNAL(hook, signals)[i]))
            return 0;
    }
    if (!infolist_new_var_integer (item, "num_signals",
                                   HOOK_SIGNAL(hook, num_signals)))
        return 0;

    return 1;
}

/*
 * Print signal hook data in WeeChat log file (usually for crash dump).
 */

void
hook_signal_print_log (struct t_hook *hook)
{
    int i;

    if (!hook || !hook->hook_data)
        return;

    log_printf ("  signal data:");
    log_printf ("    callback. . . . . . . : %p", HOOK_SIGNAL(hook, callback));
    log_printf ("    signals:");
    for (i = 0; i < HOOK_SIGNAL(hook, num_signals); i++)
    {
        log_printf ("      '%s'", HOOK_SIGNAL(hook, signals)[i]);
    }
}