source: mainline/uspace/srv/taskmon/taskmon.c

/*
 * Copyright (c) 2025 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup taskmon
 * @brief
 * @{
 */
/**
 * @file
 */

#include <async.h>
#include <errno.h>
#include <macros.h>
#include <ipc/services.h>
#include <ipc/corecfg.h>
#include <loc.h>
#include <sif.h>
#include <stdio.h>
#include <str.h>
#include <str_error.h>
#include <task.h>

#define NAME  "taskmon"

static const char *taskmon_cfg_path = "/w/cfg/taskmon.sif";

static bool write_core_files;

static errno_t taskmon_load_cfg(const char *);
static errno_t taskmon_save_cfg(const char *);
static void corecfg_client_conn(ipc_call_t *, void *);

static void fault_event(ipc_call_t *call, void *arg)
{
        const char *fname;
        char *s_taskid;
        char *dump_fname;
        errno_t rc;

        task_id_t taskid;
        uintptr_t thread;

        taskid = MERGE_LOUP32(ipc_get_arg1(call), ipc_get_arg2(call));
        thread = ipc_get_arg3(call);

        if (asprintf(&s_taskid, "%" PRIu64, taskid) < 0) {
                printf("Memory allocation failed.\n");
                return;
        }

        printf(NAME ": Task %" PRIu64 " fault in thread %p.\n", taskid,
            (void *) thread);

        fname = "/app/taskdump";

        if (write_core_files) {
                if (asprintf(&dump_fname, "/data/core%" PRIu64, taskid) < 0) {
                        printf("Memory allocation failed.\n");
                        return;
                }

                printf(NAME ": Executing %s -c %s -t %s\n", fname, dump_fname, s_taskid);
                rc = task_spawnl(NULL, NULL, fname, fname, "-c", dump_fname, "-t", s_taskid,
                    NULL);
        } else {
                printf(NAME ": Executing %s -t %s\n", fname, s_taskid);
                rc = task_spawnl(NULL, NULL, fname, fname, "-t", s_taskid, NULL);
        }

        if (rc != EOK) {
                printf("%s: Error spawning %s (%s).\n", NAME, fname,
                    str_error(rc));
        }
}

static void corecfg_get_enable_srv(ipc_call_t *icall)
{
        async_answer_1(icall, EOK, write_core_files);
}

static void corecfg_set_enable_srv(ipc_call_t *icall)
{
        write_core_files = ipc_get_arg1(icall);
        async_answer_0(icall, EOK);
        (void) taskmon_save_cfg(taskmon_cfg_path);
}

static void corecfg_client_conn(ipc_call_t *icall, void *arg)
{
        /* Accept the connection */
        async_accept_0(icall);

        while (true) {
                ipc_call_t call;
                async_get_call(&call);
                sysarg_t method = ipc_get_imethod(&call);

                if (!method) {
                        /* The other side has hung up */
                        async_answer_0(&call, EOK);
                        return;
                }

                switch (method) {
                case CORECFG_GET_ENABLE:
                        corecfg_get_enable_srv(&call);
                        break;
                case CORECFG_SET_ENABLE:
                        corecfg_set_enable_srv(&call);
                        break;
                default:
                        async_answer_0(&call, ENOTSUP);
                }
        }
}

/** Load task monitor configuration from SIF file.
 *
 * @param cfgpath Configuration file path
 *
 * @return EOK on success or an error code
 */
static errno_t taskmon_load_cfg(const char *cfgpath)
{
        sif_doc_t *doc = NULL;
        sif_node_t *rnode;
        sif_node_t *ncorefiles;
        const char *ntype;
        const char *swrite;
        errno_t rc;

        rc = sif_load(cfgpath, &doc);
        if (rc != EOK)
                goto error;

        rnode = sif_get_root(doc);
        ncorefiles = sif_node_first_child(rnode);
        ntype = sif_node_get_type(ncorefiles);
        if (str_cmp(ntype, "corefiles") != 0) {
                rc = EIO;
                goto error;
        }

        swrite = sif_node_get_attr(ncorefiles, "write");
        if (swrite == NULL) {
                rc = EIO;
                goto error;
        }

        if (str_cmp(swrite, "y") == 0) {
                write_core_files = true;
        } else if (str_cmp(swrite, "n") == 0) {
                write_core_files = false;
        } else {
                rc = EIO;
                goto error;
        }

        sif_delete(doc);
        return EOK;
error:
        if (doc != NULL)
                sif_delete(doc);
        return rc;
}

/** Save task monitor configuration to SIF file.
 *
 * @param cfgpath Configuration file path
 *
 * @return EOK on success or an error code
 */
static errno_t taskmon_save_cfg(const char *cfgpath)
{
        sif_doc_t *doc = NULL;
        sif_node_t *rnode;
        sif_node_t *ncorefiles;
        errno_t rc;

        rc = sif_new(&doc);
        if (rc != EOK)
                goto error;

        rnode = sif_get_root(doc);
        rc = sif_node_append_child(rnode, "corefiles", &ncorefiles);
        if (rc != EOK)
                goto error;

        rc = sif_node_set_attr(ncorefiles, "write",
            write_core_files ? "y" : "n");
        if (rc != EOK)
                goto error;

        rc = sif_save(doc, cfgpath);
        if (rc != EOK)
                goto error;

        sif_delete(doc);
        return EOK;
error:
        if (doc != NULL)
                sif_delete(doc);
        return rc;
}

int main(int argc, char *argv[])
{
        loc_srv_t *srv;

        printf("%s: Task Monitoring Service\n", NAME);

#ifdef CONFIG_WRITE_CORE_FILES
        write_core_files = true;
#else
        write_core_files = false;
#endif
        (void) taskmon_load_cfg(taskmon_cfg_path);

        if (async_event_subscribe(EVENT_FAULT, fault_event, NULL) != EOK) {
                printf("%s: Error registering fault notifications.\n", NAME);
                return -1;
        }

        async_set_fallback_port_handler(corecfg_client_conn, NULL);

        errno_t rc = loc_server_register(NAME, &srv);
        if (rc != EOK) {
                printf("%s: Failed registering server: %s.\n",
                    NAME, str_error(rc));
                return -1;
        }

        service_id_t sid;
        rc = loc_service_register(srv, SERVICE_NAME_CORECFG,
            fallback_port_id, &sid);
        if (rc != EOK) {
                loc_server_unregister(srv);
                printf("%s: Failed registering service: %s.\n",
                    NAME, str_error(rc));
                return -1;
        }

        task_retval(0);
        async_manager();

        return 0;
}

/** @}
 */