source: mainline/uspace/srv/sysman/units/unit_cfg.c@ 241f1985

/*
 * Copyright (c) 2015 Michal Koutny
 * 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.
 */

#include <adt/list.h>
#include <assert.h>
#include <conf/configuration.h>
#include <conf/ini.h>
#include <conf/text_parse.h>
#include <dirent.h>
#include <errno.h>
#include <stdlib.h>
#include <str.h>
#include <sysman/unit.h>

#include "repo.h"
#include "log.h"
#include "unit.h"
#include "util.h"

static const char *section_name = "Configuration";

static config_item_t unit_configuration[] = {
        {"Path", &config_parse_string, offsetof(unit_cfg_t, path), NULL},
        CONFIGURATION_ITEM_SENTINEL
};

/**
 * TODO refactor path handling and rename to 'load from file'
 *
 * @param[out]  unit_ptr   Unit loaded from the file. Undefined when function fails.
 */
static errno_t cfg_parse_file(const char *dirname, const char *filename,
    unit_t **unit_ptr)
{
        errno_t rc = EOK;
        unit_t *new_unit = NULL;
        char *fn = NULL;
        ini_configuration_t ini_conf;
        text_parse_t text_parse;

        ini_configuration_init(&ini_conf);
        text_parse_init(&text_parse);

        const char *last_sep = str_rchr(filename, UNIT_NAME_SEPARATOR);
        if (last_sep == NULL) {
                rc = EINVAL;
                goto finish;
        }

        const char *unit_name = filename;
        const char *unit_type_name = last_sep + 1;

        unit_type_t unit_type = unit_type_name_to_type(unit_type_name);
        if (unit_type == UNIT_TYPE_INVALID) {
                rc = EINVAL;
                goto finish;
        }
        
        /* We parse files as part of ongoing repo transaction (locked). */
        unit_t *u = repo_find_unit_by_name_unsafe(unit_name);
        if (u != NULL) {
                // TODO allow updating configuration of existing unit
                rc = EEXIST;
                goto finish;
        } else {
                new_unit = u = unit_create(unit_type);
                new_unit->name = str_dup(unit_name);
                if (new_unit->name == NULL) {
                        rc = ENOMEM;
                        goto finish;
                }
        }
        if (u == NULL) {
                rc = ENOMEM;
                goto finish;
        }
        assert(u->type == unit_type);

        fn = util_compose_path(dirname, filename);
        if (fn == NULL) {
                rc = ENOMEM;
                goto finish;
        }

        /* Parse INI file to ini_conf structure */
        rc = ini_parse_file(fn, &ini_conf, &text_parse);
        switch (rc) {
        case EOK:
                /* This is fine */
                break;
        case EINVAL:
                goto dump_parse;
                break;
        default:
                sysman_log(LVL_WARN,
                    "Cannot parse '%s' (%i).", fn, rc);
                goto finish;
        }

        /* Parse ini structure */
        rc = unit_load(u, &ini_conf, &text_parse);
        *unit_ptr = u;

        /*
         * Here we just continue undisturbed by errors, they'll be returned in
         * 'finish' block and potential parse errors (or none) will be logged
         * in 'dump_parse' block.
         */

dump_parse:
        list_foreach(text_parse.errors, link, text_parse_error_t, err) {
                sysman_log(LVL_WARN,
                    "Error (%i) when parsing '%s' on line %lu.",
                    err->parse_errno, fn, err->lineno);
        }

finish:
        free(fn);
        ini_configuration_deinit(&ini_conf);
        text_parse_deinit(&text_parse);
        if (rc != EOK) {
                unit_destroy(&new_unit);
        }

        return rc;
}

static errno_t cfg_load_configuration(const char *path)
{
        DIR *dir;
        struct dirent *de;

        dir = opendir(path);
        if (dir == NULL) {
                sysman_log(LVL_ERROR,
                    "Cannot open configuration directory '%s'", path);
                return EIO;
        }

        repo_begin_update();

        while ((de = readdir(dir))) {
                unit_t *unit = NULL;
                errno_t rc = cfg_parse_file(path, de->d_name, &unit);
                if (rc != EOK) {
                        sysman_log(LVL_WARN, "Cannot load unit from file %s/%s",
                            path, de->d_name);
                        /*
                         * Ignore error for now, we'll fail only when we're
                         * unable to resolve dependency names.
                         */
                        continue;
                }

                assert(unit->repo_state == REPO_EMBRYO);
                repo_add_unit(unit);
        }
        closedir(dir);

        errno_t rc = repo_resolve_references();
        if (rc != EOK) {
                repo_rollback();
                return rc;
        }

        repo_commit();
        return EOK;
}

static void unit_cfg_init(unit_t *unit)
{
        unit_cfg_t *u_cfg = CAST_CFG(unit);
        assert(u_cfg);
}

static void unit_cfg_destroy(unit_t *unit)
{
        unit_cfg_t *u_cfg = CAST_CFG(unit);
        assert(u_cfg);

        free(u_cfg->path);
}

static errno_t unit_cfg_load(unit_t *unit, ini_configuration_t *ini_conf,
    text_parse_t *text_parse)
{
        unit_cfg_t *u_cfg = CAST_CFG(unit);
        assert(u_cfg);

        ini_section_t *section = ini_get_section(ini_conf, section_name);
        if (section == NULL) {
                sysman_log(LVL_ERROR,
                    "Expected section '%s' in configuration of unit '%s'",
                    section_name, unit_name(unit));
                return ENOENT;
        }

        return config_load_ini_section(unit_configuration, section, u_cfg,
            text_parse);
}

static errno_t unit_cfg_start(unit_t *unit)
{
        unit_cfg_t *u_cfg = CAST_CFG(unit);
        assert(u_cfg);

        errno_t rc = cfg_load_configuration(u_cfg->path);
        
        if (rc == EOK) {
                unit->state = STATE_STARTED;
        } else {
                unit->state = STATE_FAILED;
        }

        return rc;
}

static errno_t unit_cfg_stop(unit_t *unit)
{
        unit_cfg_t *u_cfg = CAST_CFG(unit);
        assert(u_cfg);

        /*
         * It makes no sense to stop configuration (i.e. unload it), however,
         * lets virtually stop it not to make obstructions for potential
         * restart = reload of configuration.
         */
        unit->state = STATE_STOPPED;
        return EOK;
}

static void unit_cfg_exposee_created(unit_t *unit)
{
        /* Configuration has no exposees. */
        assert(false);
}

static void unit_cfg_fail(unit_t *unit)
{
        /* Configuration cannot async fail. */
        assert(false);
}

DEFINE_UNIT_VMT(unit_cfg)