/*
 *  ircd-ratbox: A slightly useful ircd.
 *  modules.c: A module loader.
 *
 *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
 *  Copyright (C) 1996-2002 Hybrid Development Team
 *  Copyright (C) 2002-2005 ircd-ratbox development team
 *
 *  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
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 *
 */

#include "stdinc.h"


#include "modules.h"
#include "logger.h"
#include "ircd.h"
#include "client.h"
#include "send.h"
#include "s_conf.h"
#include "s_newconf.h"
#include "numeric.h"
#include "parse.h"
#include "ircd_defs.h"
#include "match.h"
#include "s_serv.h"



/* -TimeMr14C:
 * I have moved the dl* function definitions and
 * the two functions (load_a_module / unload_a_module) to the
 * file dynlink.c
 * And also made the necessary changes to those functions
 * to comply with shl_load and friends.
 * In this file, to keep consistency with the makefile,
 * I added the ability to load *.sl files, too.
 * 27/02/2002
 */

#ifndef STATIC_MODULES

struct module **modlist = NULL;

static const char *core_module_table[] = {
    "m_ban",
    "m_die",
    "m_error",
    "m_join",
    "m_kick",
    "m_kill",
    "m_message",
    "m_metadata",
    "m_mode",
    "m_nick",
    "m_part",
    "m_quit",
    "m_server",
    "m_squit",
    NULL
};

#define MODS_INCREMENT 10
int num_mods = 0;
int max_mods = MODS_INCREMENT;

static rb_dlink_list mod_paths;

static int mo_modload(struct Client *, struct Client *, int, const char **);
static int mo_modlist(struct Client *, struct Client *, int, const char **);
static int mo_modreload(struct Client *, struct Client *, int, const char **);
static int mo_modunload(struct Client *, struct Client *, int, const char **);
static int mo_modrestart(struct Client *, struct Client *, int, const char **);

static int me_modload(struct Client *, struct Client *, int, const char **);
static int me_modlist(struct Client *, struct Client *, int, const char **);
static int me_modreload(struct Client *, struct Client *, int, const char **);
static int me_modunload(struct Client *, struct Client *, int, const char **);
static int me_modrestart(struct Client *, struct Client *, int, const char **);

static int do_modload(struct Client *, const char *);
static int do_modunload(struct Client *, const char *);
static int do_modreload(struct Client *, const char *);
static int do_modlist(struct Client *, const char *);
static int do_modrestart(struct Client *);

struct Message modload_msgtab = {
    "MODLOAD", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, mg_not_oper, mg_ignore, mg_ignore, {me_modload, 2}, {mo_modload, 2}}
};

struct Message modunload_msgtab = {
    "MODUNLOAD", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, mg_not_oper, mg_ignore, mg_ignore, {me_modunload, 2}, {mo_modunload, 2}}
};

struct Message modreload_msgtab = {
    "MODRELOAD", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, mg_not_oper, mg_ignore, mg_ignore, {me_modreload, 2}, {mo_modreload, 2}}
};

struct Message modlist_msgtab = {
    "MODLIST", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, mg_not_oper, mg_ignore, mg_ignore, {me_modlist, 0}, {mo_modlist, 0}}
};

struct Message modrestart_msgtab = {
    "MODRESTART", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, mg_not_oper, mg_ignore, mg_ignore, {me_modrestart, 0}, {mo_modrestart, 0}}
};

void
modules_init(void)
{
    mod_add_cmd(&modload_msgtab);
    mod_add_cmd(&modunload_msgtab);
    mod_add_cmd(&modreload_msgtab);
    mod_add_cmd(&modlist_msgtab);
    mod_add_cmd(&modrestart_msgtab);

    /* Add the default paths we look in to the module system --nenolod */
    mod_add_path(MODPATH);
    mod_add_path(AUTOMODPATH);
}

/* mod_find_path()
 *
 * input	- path
 * output	- none
 * side effects - returns a module path from path
 */
static struct module_path *
mod_find_path(const char *path)
{
    rb_dlink_node *ptr;
    struct module_path *mpath;

    RB_DLINK_FOREACH(ptr, mod_paths.head) {
        mpath = ptr->data;

        if(!strcmp(path, mpath->path))
            return mpath;
    }

    return NULL;
}

/* mod_add_path
 *
 * input	- path
 * ouput	-
 * side effects - adds path to list
 */
void
mod_add_path(const char *path)
{
    struct module_path *pathst;

    if(mod_find_path(path))
        return;

    pathst = rb_malloc(sizeof(struct module_path));

    strcpy(pathst->path, path);
    rb_dlinkAddAlloc(pathst, &mod_paths);
}

/* mod_clear_paths()
 *
 * input	-
 * output	-
 * side effects - clear the lists of paths
 */
void
mod_clear_paths(void)
{
    rb_dlink_node *ptr, *next_ptr;

    RB_DLINK_FOREACH_SAFE(ptr, next_ptr, mod_paths.head) {
        rb_free(ptr->data);
        rb_free_rb_dlink_node(ptr);
    }

    mod_paths.head = mod_paths.tail = NULL;
    mod_paths.length = 0;
}

/* findmodule_byname
 *
 * input        -
 * output       -
 * side effects -
 */

int
findmodule_byname(const char *name)
{
    int i;

    for (i = 0; i < num_mods; i++) {
        if(!irccmp(modlist[i]->name, name))
            return i;
    }
    return -1;
}

/* load_all_modules()
 *
 * input        -
 * output       -
 * side effects -
 */
void
load_all_modules(int warn)
{
    DIR *system_module_dir = NULL;
    struct dirent *ldirent = NULL;
    char module_fq_name[PATH_MAX + 1];
    int len;

    modules_init();

    modlist = (struct module **) rb_malloc(sizeof(struct module) * (MODS_INCREMENT));

    max_mods = MODS_INCREMENT;

    system_module_dir = opendir(AUTOMODPATH);

    if(system_module_dir == NULL) {
        ilog(L_MAIN, "Could not load modules from %s: %s", AUTOMODPATH, strerror(errno));
        return;
    }

    while ((ldirent = readdir(system_module_dir)) != NULL) {
        len = strlen(ldirent->d_name);
        if((len > 3) && !strcmp(ldirent->d_name+len-3, SHARED_SUFFIX)) {
            (void) rb_snprintf(module_fq_name, sizeof(module_fq_name), "%s/%s", AUTOMODPATH, ldirent->d_name);
            (void) load_a_module(module_fq_name, warn, 0);
        }

    }
    (void) closedir(system_module_dir);
}

/* load_core_modules()
 *
 * input        -
 * output       -
 * side effects - core modules are loaded, if any fail, kill ircd
 */
void
load_core_modules(int warn)
{
    char module_name[MAXPATHLEN];
    int i;


    for (i = 0; core_module_table[i]; i++) {
        rb_snprintf(module_name, sizeof(module_name), "%s/%s%s", MODPATH,
                    core_module_table[i], SHARED_SUFFIX);

        if(load_a_module(module_name, warn, 1) == -1) {
            ilog(L_MAIN,
                 "Error loading core module %s%s: terminating ircd",
                 core_module_table[i], SHARED_SUFFIX);
            exit(0);
        }
    }
}

/* load_one_module()
 *
 * input        -
 * output       -
 * side effects -
 */
int
load_one_module(const char *path, int coremodule)
{
    char modpath[MAXPATHLEN];
    rb_dlink_node *pathst;
    struct module_path *mpath;

    struct stat statbuf;

    if (server_state_foreground == 1)
        inotice("loading module %s ...", path);

    RB_DLINK_FOREACH(pathst, mod_paths.head) {
        mpath = pathst->data;

        rb_snprintf(modpath, sizeof(modpath), "%s/%s", mpath->path, path);
        if((strstr(modpath, "../") == NULL) && (strstr(modpath, "/..") == NULL)) {
            if(stat(modpath, &statbuf) == 0) {
                if(S_ISREG(statbuf.st_mode)) {
                    /* Regular files only please */
                    if(coremodule)
                        return load_a_module(modpath, 1, 1);
                    else
                        return load_a_module(modpath, 1, 0);
                }
            }

        }
    }

    sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Cannot locate module %s", path);
    return -1;
}


/* load a module .. */
static int
mo_modload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!IsOperAdmin(source_p)) {
        sendto_one(source_p, form_str(ERR_NOPRIVS),
                   me.name, source_p->name, "admin");
        return 0;
    }

    if(parc > 2) {
        sendto_match_servs(source_p, parv[2], CAP_ENCAP, NOCAPS,
                           "ENCAP %s MODLOAD %s", parv[2], parv[1]);
        if (match(parv[2], me.name) == 0)
            return 0;
    }

    return do_modload(source_p, parv[1]);
}

static int
me_modload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!find_shared_conf(source_p->username, source_p->host, source_p->servptr->name, SHARED_MODULE)) {
        sendto_one_notice(source_p, ":*** You do not have an appropriate shared block "
                          "to load modules on this server.");
        return 0;
    }

    return do_modload(source_p, parv[1]);
}

static int
do_modload(struct Client *source_p, const char *module)
{
    char *m_bn = rb_basename(module);

    if(findmodule_byname(m_bn) != -1) {
        sendto_one_notice(source_p, ":Module %s is already loaded", m_bn);
        rb_free(m_bn);
        return 0;
    }

    load_one_module(module, 0);

    rb_free(m_bn);

    return 0;
}


/* unload a module .. */
static int
mo_modunload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!IsOperAdmin(source_p)) {
        sendto_one(source_p, form_str(ERR_NOPRIVS),
                   me.name, source_p->name, "admin");
        return 0;
    }

    if(parc > 2) {
        sendto_match_servs(source_p, parv[2], CAP_ENCAP, NOCAPS,
                           "ENCAP %s MODUNLOAD %s", parv[2], parv[1]);
        if (match(parv[2], me.name) == 0)
            return 0;
    }

    return do_modunload(source_p, parv[1]);
}

static int
me_modunload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!find_shared_conf(source_p->username, source_p->host, source_p->servptr->name, SHARED_MODULE)) {
        sendto_one_notice(source_p, ":*** You do not have an appropriate shared block "
                          "to load modules on this server.");
        return 0;
    }

    return do_modunload(source_p, parv[1]);
}

static int
do_modunload(struct Client *source_p, const char *module)
{
    int modindex;
    char *m_bn = rb_basename(module);

    if((modindex = findmodule_byname(m_bn)) == -1) {
        sendto_one_notice(source_p, ":Module %s is not loaded", m_bn);
        rb_free(m_bn);
        return 0;
    }

    if(modlist[modindex]->core == 1) {
        sendto_one_notice(source_p, ":Module %s is a core module and may not be unloaded", m_bn);
        rb_free(m_bn);
        return 0;
    }

    if(unload_one_module(m_bn, 1) == -1) {
        sendto_one_notice(source_p, ":Module %s is not loaded", m_bn);
    }

    rb_free(m_bn);
    return 0;
}

/* unload and load in one! */
static int
mo_modreload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!IsOperAdmin(source_p)) {
        sendto_one(source_p, form_str(ERR_NOPRIVS),
                   me.name, source_p->name, "admin");
        return 0;
    }

    if(parc > 2) {
        sendto_match_servs(source_p, parv[2], CAP_ENCAP, NOCAPS,
                           "ENCAP %s MODRELOAD %s", parv[2], parv[1]);
        if (match(parv[2], me.name) == 0)
            return 0;
    }

    return do_modreload(source_p, parv[1]);
}

static int
me_modreload(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!find_shared_conf(source_p->username, source_p->host, source_p->servptr->name, SHARED_MODULE)) {
        sendto_one_notice(source_p, ":*** You do not have an appropriate shared block "
                          "to load modules on this server.");
        return 0;
    }

    return do_modreload(source_p, parv[1]);
}

static int
do_modreload(struct Client *source_p, const char *module)
{
    int modindex;
    int check_core;
    char *m_bn = rb_basename(module);

    if((modindex = findmodule_byname(m_bn)) == -1) {
        sendto_one_notice(source_p, ":Module %s is not loaded", m_bn);
        rb_free(m_bn);
        return 0;
    }

    check_core = modlist[modindex]->core;

    if(unload_one_module(m_bn, 1) == -1) {
        sendto_one_notice(source_p, ":Module %s is not loaded", m_bn);
        rb_free(m_bn);
        return 0;
    }

    if((load_one_module(m_bn, check_core) == -1) && check_core) {
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Error reloading core module: %s: terminating ircd", m_bn);
        ilog(L_MAIN, "Error loading core module %s: terminating ircd", m_bn);
        exit(0);
    }

    rb_free(m_bn);
    return 0;
}

/* list modules .. */
static int
mo_modlist(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!IsOperAdmin(source_p)) {
        sendto_one(source_p, form_str(ERR_NOPRIVS),
                   me.name, source_p->name, "admin");
        return 0;
    }

    if(parc > 2) {
        sendto_match_servs(source_p, parv[2], CAP_ENCAP, NOCAPS,
                           "ENCAP %s MODLIST %s", parv[2], parv[1]);
        if (match(parv[2], me.name) == 0)
            return 0;
    }

    return do_modlist(source_p, parc > 1 ? parv[1] : 0);
}

static int
me_modlist(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!find_shared_conf(source_p->username, source_p->host, source_p->servptr->name, SHARED_MODULE)) {
        sendto_one_notice(source_p, ":*** You do not have an appropriate shared block "
                          "to load modules on this server.");
        return 0;
    }

    return do_modlist(source_p, parv[1]);
}

static int
do_modlist(struct Client *source_p, const char *pattern)
{
    int i;

    for (i = 0; i < num_mods; i++) {
        if(pattern) {
            if(match(pattern, modlist[i]->name)) {
                sendto_one(source_p, form_str(RPL_MODLIST),
                           me.name, source_p->name,
                           modlist[i]->name,
                           modlist[i]->address,
                           modlist[i]->version, modlist[i]->core ? "(core)" : "");
            }
        } else {
            sendto_one(source_p, form_str(RPL_MODLIST),
                       me.name, source_p->name, modlist[i]->name,
                       modlist[i]->address, modlist[i]->version,
                       modlist[i]->core ? "(core)" : "");
        }
    }

    sendto_one(source_p, form_str(RPL_ENDOFMODLIST), me.name, source_p->name);
    return 0;
}

/* unload and reload all modules */
static int
mo_modrestart(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!IsOperAdmin(source_p)) {
        sendto_one(source_p, form_str(ERR_NOPRIVS),
                   me.name, source_p->name, "admin");
        return 0;
    }

    if(parc > 1) {
        sendto_match_servs(source_p, parv[1], CAP_ENCAP, NOCAPS,
                           "ENCAP %s MODRESTART", parv[1]);
        if (match(parv[1], me.name) == 0)
            return 0;
    }

    return do_modrestart(source_p);
}

static int
me_modrestart(struct Client *client_p, struct Client *source_p, int parc, const char **parv)
{
    if(!find_shared_conf(source_p->username, source_p->host, source_p->servptr->name, SHARED_MODULE)) {
        sendto_one_notice(source_p, ":*** You do not have an appropriate shared block "
                          "to load modules on this server.");
        return 0;
    }

    return do_modrestart(source_p);
}

static int
do_modrestart(struct Client *source_p)
{
    int modnum;

    sendto_one_notice(source_p, ":Reloading all modules");

    modnum = num_mods;
    while (num_mods)
        unload_one_module(modlist[0]->name, 0);

    load_all_modules(0);
    load_core_modules(0);
    rehash(0);

    sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                           "Module Restart: %d modules unloaded, %d modules loaded",
                           modnum, num_mods);
    ilog(L_MAIN, "Module Restart: %d modules unloaded, %d modules loaded", modnum, num_mods);
    return 0;
}



#ifndef RTLD_NOW
#define RTLD_NOW RTLD_LAZY	/* openbsd deficiency */
#endif

#ifndef RTLD_LOCAL
#define RTLD_LOCAL 0
#endif

#ifdef CHARYBDIS_PROFILE
# ifndef RTLD_PROFILE
#  warning libdl may not support profiling, sucks. :(
#  define RTLD_PROFILE 0
# endif
#endif

static void increase_modlist(void);

#define MODS_INCREMENT 10

static char unknown_ver[] = "<unknown>";

/* This file contains the core functions to use dynamic libraries.
 * -TimeMr14C
 */


#ifdef HAVE_MACH_O_DYLD_H
/*
** jmallett's dl*(3) shims for NSModule(3) systems.
*/
#include <mach-o/dyld.h>

#ifndef HAVE_DLOPEN
#ifndef	RTLD_LAZY
#define RTLD_LAZY 2185		/* built-in dl*(3) don't care */
#endif

void undefinedErrorHandler(const char *);
NSModule multipleErrorHandler(NSSymbol, NSModule, NSModule);
void linkEditErrorHandler(NSLinkEditErrors, int, const char *, const char *);
char *dlerror(void);
void *dlopen(char *, int);
int dlclose(void *);
void *dlsym(void *, char *);

static int firstLoad = TRUE;
static int myDlError;
static char *myErrorTable[] = { "Loading file as object failed\n",
                                "Loading file as object succeeded\n",
                                "Not a valid shared object\n",
                                "Architecture of object invalid on this architecture\n",
                                "Invalid or corrupt image\n",
                                "Could not access object\n",
                                "NSCreateObjectFileImageFromFile failed\n",
                                NULL
                              };

void
undefinedErrorHandler(const char *symbolName)
{
    sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Undefined symbol: %s", symbolName);
    ilog(L_MAIN, "Undefined symbol: %s", symbolName);
    return;
}

NSModule
multipleErrorHandler(NSSymbol s, NSModule old, NSModule new)
{
    /* XXX
     ** This results in substantial leaking of memory... Should free one
     ** module, maybe?
     */
    sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                           "Symbol `%s' found in `%s' and `%s'",
                           NSNameOfSymbol(s), NSNameOfModule(old), NSNameOfModule(new));
    ilog(L_MAIN, "Symbol `%s' found in `%s' and `%s'",
         NSNameOfSymbol(s), NSNameOfModule(old), NSNameOfModule(new));
    /* We return which module should be considered valid, I believe */
    return new;
}

void
linkEditErrorHandler(NSLinkEditErrors errorClass, int errnum,
                     const char *fileName, const char *errorString)
{
    sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                           "Link editor error: %s for %s", errorString, fileName);
    ilog(L_MAIN, "Link editor error: %s for %s", errorString, fileName);
    return;
}

char *
dlerror(void)
{
    return myDlError == NSObjectFileImageSuccess ? NULL : myErrorTable[myDlError % 7];
}

void *
dlopen(char *filename, int unused)
{
    NSObjectFileImage myImage;
    NSModule myModule;

    if(firstLoad) {
        /*
         ** If we are loading our first symbol (huzzah!) we should go ahead
         ** and install link editor error handling!
         */
        NSLinkEditErrorHandlers linkEditorErrorHandlers;

        linkEditorErrorHandlers.undefined = undefinedErrorHandler;
        linkEditorErrorHandlers.multiple = multipleErrorHandler;
        linkEditorErrorHandlers.linkEdit = linkEditErrorHandler;
        NSInstallLinkEditErrorHandlers(&linkEditorErrorHandlers);
        firstLoad = FALSE;
    }
    myDlError = NSCreateObjectFileImageFromFile(filename, &myImage);
    if(myDlError != NSObjectFileImageSuccess) {
        return NULL;
    }
    myModule = NSLinkModule(myImage, filename, NSLINKMODULE_OPTION_PRIVATE);
    return (void *) myModule;
}

int
dlclose(void *myModule)
{
    NSUnLinkModule(myModule, FALSE);
    return 0;
}

void *
dlsym(void *myModule, char *mySymbolName)
{
    NSSymbol mySymbol;

    mySymbol = NSLookupSymbolInModule((NSModule) myModule, mySymbolName);
    return NSAddressOfSymbol(mySymbol);
}
#endif
#endif


/*
 * HPUX dl compat functions
 */
#if defined(HAVE_SHL_LOAD) && !defined(HAVE_DLOPEN)
#define RTLD_LAZY BIND_DEFERRED
#define RTLD_GLOBAL DYNAMIC_PATH
#define dlopen(file,mode) (void *)shl_load((file), (mode), (long) 0)
#define dlclose(handle) shl_unload((shl_t)(handle))
#define dlsym(handle,name) hpux_dlsym(handle,name)
#define dlerror() strerror(errno)

static void *
hpux_dlsym(void *handle, char *name)
{
    void *sym_addr;
    if(!shl_findsym((shl_t *) & handle, name, TYPE_UNDEFINED, &sym_addr))
        return sym_addr;
    return NULL;
}

#endif

/* unload_one_module()
 *
 * inputs	- name of module to unload
 *		- 1 to say modules unloaded, 0 to not
 * output	- 0 if successful, -1 if error
 * side effects	- module is unloaded
 */
int
unload_one_module(const char *name, int warn)
{
    int modindex;

    if((modindex = findmodule_byname(name)) == -1)
        return -1;

    /*
     ** XXX - The type system in C does not allow direct conversion between
     ** data and function pointers, but as it happens, most C compilers will
     ** safely do this, however it is a theoretical overlow to cast as we
     ** must do here.  I have library functions to take care of this, but
     ** despite being more "correct" for the C language, this is more
     ** practical.  Removing the abuse of the ability to cast ANY pointer
     ** to and from an integer value here will break some compilers.
     **          -jmallett
     */
    /* Left the comment in but the code isn't here any more         -larne */
    switch (modlist[modindex]->mapi_version) {
    case 1: {
        struct mapi_mheader_av1 *mheader = modlist[modindex]->mapi_header;
        if(mheader->mapi_command_list) {
            struct Message **m;
            for (m = mheader->mapi_command_list; *m; ++m)
                mod_del_cmd(*m);
        }

        /* hook events are never removed, we simply lose the
         * ability to call them --fl
         */
        if(mheader->mapi_hfn_list) {
            mapi_hfn_list_av1 *m;
            for (m = mheader->mapi_hfn_list; m->hapi_name; ++m)
                remove_hook(m->hapi_name, m->fn);
        }

        if(mheader->mapi_unregister)
            mheader->mapi_unregister();
        break;
    }
    default:
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Unknown/unsupported MAPI version %d when unloading %s!",
                               modlist[modindex]->mapi_version, modlist[modindex]->name);
        ilog(L_MAIN, "Unknown/unsupported MAPI version %d when unloading %s!",
             modlist[modindex]->mapi_version, modlist[modindex]->name);
        break;
    }

    dlclose(modlist[modindex]->address);

    rb_free(modlist[modindex]->name);
    memmove(&modlist[modindex], &modlist[modindex + 1],
            sizeof(struct module) * ((num_mods - 1) - modindex));

    if(num_mods != 0)
        num_mods--;

    if(warn == 1) {
        ilog(L_MAIN, "Module %s unloaded", name);
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Module %s unloaded", name);
    }

    return 0;
}


/*
 * load_a_module()
 *
 * inputs	- path name of module, int to notice, int of core
 * output	- -1 if error 0 if success
 * side effects - loads a module if successful
 */
int
load_a_module(const char *path, int warn, int core)
{
    void *tmpptr = NULL;

    char *mod_basename;
    const char *ver;

    int *mapi_version;

    mod_basename = rb_basename(path);

#ifdef CHARYBDIS_PROFILE
    tmpptr = dlopen(path, RTLD_NOW | RTLD_LOCAL | RTLD_PROFILE);
#else
    tmpptr = dlopen(path, RTLD_NOW | RTLD_LOCAL);
#endif

    if(tmpptr == NULL) {
        const char *err = dlerror();

        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Error loading module %s: %s", mod_basename, err);
        ilog(L_MAIN, "Error loading module %s: %s", mod_basename, err);
        rb_free(mod_basename);
        return -1;
    }


    /*
     * _mheader is actually a struct mapi_mheader_*, but mapi_version
     * is always the first member of this structure, so we treate it
     * as a single int in order to determine the API version.
     *      -larne.
     */
    mapi_version = (int *) (uintptr_t) dlsym(tmpptr, "_mheader");
    if((mapi_version == NULL
        && (mapi_version = (int *) (uintptr_t) dlsym(tmpptr, "__mheader")) == NULL)
       || MAPI_MAGIC(*mapi_version) != MAPI_MAGIC_HDR) {
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Data format error: module %s has no MAPI header.",
                               mod_basename);
        ilog(L_MAIN, "Data format error: module %s has no MAPI header.", mod_basename);
        (void) dlclose(tmpptr);
        rb_free(mod_basename);
        return -1;
    }

    switch (MAPI_VERSION(*mapi_version)) {
    case 1: {
        struct mapi_mheader_av1 *mheader = (struct mapi_mheader_av1 *) mapi_version;	/* see above */
        if(mheader->mapi_register && (mheader->mapi_register() == -1)) {
            ilog(L_MAIN, "Module %s indicated failure during load.",
                 mod_basename);
            sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                                   "Module %s indicated failure during load.",
                                   mod_basename);
            dlclose(tmpptr);
            rb_free(mod_basename);
            return -1;
        }
        if(mheader->mapi_command_list) {
            struct Message **m;
            for (m = mheader->mapi_command_list; *m; ++m)
                mod_add_cmd(*m);
        }

        if(mheader->mapi_hook_list) {
            mapi_hlist_av1 *m;
            for (m = mheader->mapi_hook_list; m->hapi_name; ++m)
                *m->hapi_id = register_hook(m->hapi_name);
        }

        if(mheader->mapi_hfn_list) {
            mapi_hfn_list_av1 *m;
            for (m = mheader->mapi_hfn_list; m->hapi_name; ++m)
                add_hook(m->hapi_name, m->fn);
        }

        ver = mheader->mapi_module_version;
        break;
    }

    default:
        ilog(L_MAIN, "Module %s has unknown/unsupported MAPI version %d.",
             mod_basename, MAPI_VERSION(*mapi_version));
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Module %s has unknown/unsupported MAPI version %d.",
                               mod_basename, *mapi_version);
        dlclose(tmpptr);
        rb_free(mod_basename);
        return -1;
    }

    if(ver == NULL)
        ver = unknown_ver;

    increase_modlist();

    modlist[num_mods] = rb_malloc(sizeof(struct module));
    modlist[num_mods]->address = tmpptr;
    modlist[num_mods]->version = ver;
    modlist[num_mods]->core = core;
    modlist[num_mods]->name = rb_strdup(mod_basename);
    modlist[num_mods]->mapi_header = mapi_version;
    modlist[num_mods]->mapi_version = MAPI_VERSION(*mapi_version);
    num_mods++;

    if(warn == 1) {
        sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
                               "Module %s [version: %s; MAPI version: %d] loaded at 0x%lx",
                               mod_basename, ver, MAPI_VERSION(*mapi_version),
                               (unsigned long) tmpptr);
        ilog(L_MAIN, "Module %s [version: %s; MAPI version: %d] loaded at 0x%lx",
             mod_basename, ver, MAPI_VERSION(*mapi_version), (unsigned long) tmpptr);
    }
    rb_free(mod_basename);
    return 0;
}

/*
 * increase_modlist
 *
 * inputs	- NONE
 * output	- NONE
 * side effects	- expand the size of modlist if necessary
 */
static void
increase_modlist(void)
{
    struct module **new_modlist = NULL;

    if((num_mods + 1) < max_mods)
        return;

    new_modlist = (struct module **) rb_malloc(sizeof(struct module) *
                  (max_mods + MODS_INCREMENT));
    memcpy((void *) new_modlist, (void *) modlist, sizeof(struct module) * num_mods);

    rb_free(modlist);
    modlist = new_modlist;
    max_mods += MODS_INCREMENT;
}

#else /* STATIC_MODULES */

/* load_all_modules()
 *
 * input        -
 * output       -
 * side effects - all the msgtabs are added for static modules
 */
void
load_all_modules(int warn)
{
    load_static_modules();
}

#endif /* STATIC_MODULES */
