clixon_util_dispatcher.c

/*
 *
  ***** BEGIN LICENSE BLOCK *****
 
  Copyright (C) 2021-2022 Olof Hagsand and Rubicon Communications, LLC(Netgate)

  This file is part of CLIXON.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

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  See the License for the specific language governing permissions and
  limitations under the License.

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* Utility for testing path dispatcher
* Everything is run by options and order is significant which makes it a little special.
* For example:
* clixon_util_dispatcher -r -c / : 
*      Register cb1 with default path "/" and arg NULL, call with path /
* clixon_util_dispatcher -i 2 -p /foo -a bar -r -c /bar -c /fie
*      Register cb2 with path "/foo" and arg bar, call with path /bar then /fie
*/

#ifdef HAVE_CONFIG_H
#include "clixon_config.h" /* generated by config & autoconf */
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <limits.h>
#include <stdint.h>
#include <syslog.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/stat.h>

/* cligen */
#include <cligen/cligen.h>

/* clixon */
#include "clixon/clixon.h"
#include "clixon/clixon_backend.h"

/* Command line options to be passed to getopt(3) */
#define DISPATCHER_OPTS "hD:a:i:p:rc:"

static int
usage(char *argv0)
{
    fprintf(stderr, "usage:%s [options]\n"
            "where options are\n"
            "\t-h \t\tHelp\n"
            "\t-D <level> \t Debug - print dispatch tree\n"
            "\t-a <string>\t Argument to callback (default: NULL)\n"
            "\t-i <int>   \t Function index: 1..3 (default: 1)\n"
            "\t-p <path>  \t Registered path (default: /)\n"
            "\t-r         \t Register callback (based on -a/-i/-p setting)\n"
            "\t-c <path>  \t Call dispatcher with path\n",
            argv0
            );
    exit(0);
}

/*! Function to handle a path
 *
 * @param[in]  h        Generic handler
 * @param[in]  xpath    Registered XPath using canonical prefixes
 * @param[in]  userargs Per-call user arguments
 * @param[in]  arg      Per-path user argument
 *(
/ * Make a CB() macro to generate simple callbacks that just prints the path and arg
 */
#define CB(i) static int cb##i(void *h0, char *xpath, void *userargs, void *arg)    {  fprintf(stdout, "%s %s\n", __FUNCTION__, (char*)arg); return 0; }

CB(1)
CB(2)

int
main(int    argc,
     char **argv)
{
    int                 retval = -1;
    char               *argv0 = argv[0];
    int                 logdst = CLIXON_LOG_STDERR;
    int                 dbg = 0;
    int                 c;
    char               *arg = NULL;
    handler_function    fn = cb1;
    dispatcher_entry_t *htable = NULL;
    int                 ret;
    char               *regpath = "/"; /* Register path */
    clixon_handle       h;
    
    /* In the startup, logs to stderr & debug flag set later */
    if ((h = clixon_handle_init()) == NULL)
        goto done;
    clixon_log_init(h, "dispatcher", LOG_DEBUG, logdst); 
    
    optind = 1;
    opterr = 0;
    while ((c = getopt(argc, argv, DISPATCHER_OPTS)) != -1)
        switch (c) {
        case 'h':
            usage(argv0);
            break;
        case 'D':
            if (sscanf(optarg, "%d", &dbg) != 1)
                usage(argv0);
            break;

        case 'a' :
        case 'i' :
        case 'p' :
        case 'r' :
        case 'c' :
            break;
        default:
            usage(argv[0]);
            break;
        }
    /* 
     * Logs, error and debug to stderr or syslog, set debug level
     */
    clixon_log_init(h, "xpath", dbg?LOG_DEBUG:LOG_INFO, logdst);
    clixon_debug_init(h, dbg);
    /* Now rest of options */
    opterr = 0;
    optind = 1;
    while ((c = getopt(argc, argv, DISPATCHER_OPTS)) != -1){
        switch (c) {
        case 'D' : /* debug */
            break; /* see above */
        case 'a' : /* arg string */
            arg = optarg;
            break;
        case 'i' : /* dispatcher function: 1..3 */
            switch (atoi(optarg)){
            case 1: fn = cb1; break;
            case 2: fn = cb2; break;
                //          case 3: fn = cb3; break;
            }
            break;
        case 'p' : /* register path */
            regpath = optarg;
            break;
        case 'r' :{ /* register callback based on -a/-i/-p*/
            dispatcher_definition     x = {regpath, fn, arg};
            if (dispatcher_register_handler(&htable, &x) < 0)
                goto done;
            break;
        }
        case 'c':{ /* Execute a call using path */
            char *path = optarg;
            if ((ret = dispatcher_call_handlers(htable, NULL, path, NULL)) < 0)
                goto done;
            fprintf(stderr, "path:%s ret:%d\n", path, ret);
            break;
        }
        default:
            usage(argv[0]);
            break;
        }
    }
    if (dbg)
        dispatcher_print(stderr, 0, htable);
    dispatcher_free(htable);
    retval = 0;
 done:
    return retval;
}