/* Copyright (c) 2002-2018 Pigeonhole authors, see the included COPYING file

 */

#include "lib.h"

#include "str.h"

#include "settings-parser.h"

#include "module-dir.h"

#include "master-service.h"

#include "sieve-extensions.h"

#include "sieve-common.h"

#include "sieve-plugins.h"

/*

 * Types

 */

typedef int

(*sieve_plugin_load_func_t)(struct sieve_instance *svinst, void **context);

typedef void

(*sieve_plugin_unload_func_t)(struct sieve_instance *svinst, void *context);

struct sieve_plugin {

  struct module *module;

  void *context;

  struct sieve_plugin *next;

};

/*

 * Plugin support

 */

static struct module *sieve_modules = NULL;

static int sieve_modules_refcount = 0;

static struct module *sieve_plugin_module_find(const char *name)

{

  struct module *module;

  module = sieve_modules;

  while (module != NULL) {

    const char *mod_name;

    /* Strip module names */

    mod_name = module_get_plugin_name(module);

    if (strcmp(mod_name, name) == 0)

      return module;

    module = module->next;

  }

  return NULL;

}

int sieve_plugins_load(struct sieve_instance *svinst, const char *path,

           const char *plugins)

{

  struct module *module;

  struct module_dir_load_settings mod_set;

  const char *const *module_names;

  unsigned int i;

  /* Determine what to load */

  if (path == NULL && plugins == NULL) {

    /* From settings */

    module_names = settings_boollist_get(&svinst->set->plugins);

    path = svinst->set->plugin_dir;

  } else {

    /* From function parameters */

    const char **module_names_mod;

    if (plugins == NULL || *plugins == '\0')

      return 0;

    module_names_mod = t_strsplit_spaces(plugins, ", ");

    if (path == NULL || *path == '\0')

      path = sieve_default_settings.plugin_dir;

    for (i = 0; module_names_mod[i] != NULL; i++) {

      /* Allow giving the module names also in non-base form.

       */

      module_names_mod[i] =

        module_file_get_name(module_names_mod[i]);

    }

    module_names = module_names_mod;

  }

  if (module_names == NULL || *module_names == NULL)

    return 0;

  i_zero(&mod_set);

  mod_set.abi_version = PIGEONHOLE_ABI_VERSION;

  mod_set.binary_name = master_service_get_name(master_service);

  mod_set.setting_name = "sieve_plugins";

  mod_set.require_init_funcs = TRUE;

  mod_set.debug = svinst->debug;

  /* Load missing plugin modules */

  sieve_modules = module_dir_load_missing(sieve_modules, path,

            module_names, &mod_set);

  /* Call plugin load functions for this Sieve instance */

  if (svinst->plugins == NULL)

    sieve_modules_refcount++;

  for (i = 0; module_names[i] != NULL; i++) {

    struct sieve_plugin *plugin;

    const char *name = module_names[i];

    sieve_plugin_load_func_t load_func;

    /* Find the module */

    module = sieve_plugin_module_find(name);

    i_assert(module != NULL);

    /* Check whether the plugin is already loaded in this instance */

    plugin = svinst->plugins;

    while (plugin != NULL) {

      if (plugin->module == module)

        break;

      plugin = plugin->next;

    }

    /* Skip it if it is loaded already */

    if (plugin != NULL)

      continue;

    /* Create plugin list item */

    plugin = p_new(svinst->pool, struct sieve_plugin, 1);

    plugin->module = module;

    /* Call load function */

    load_func = (sieve_plugin_load_func_t)

      module_get_symbol(module,

        t_strdup_printf("%s_load", module->name));

    if (load_func != NULL &&

        load_func(svinst, &plugin->context) < 0)

      return -1;

    /* Add plugin to the instance */

    if (svinst->plugins == NULL)

      svinst->plugins = plugin;

    else {

      struct sieve_plugin *plugin_last;

      plugin_last = svinst->plugins;

      while ( plugin_last->next != NULL )

        plugin_last = plugin_last->next;

      plugin_last->next = plugin;

    }

  }

  return 0;

}

void sieve_plugins_unload(struct sieve_instance *svinst)

{

  struct sieve_plugin *plugin;

  if (svinst->plugins == NULL)

    return;

  /* Call plugin unload functions for this instance */

  plugin = svinst->plugins;

  while (plugin != NULL) {

    struct module *module = plugin->module;

    sieve_plugin_unload_func_t unload_func;

    unload_func = (sieve_plugin_unload_func_t)

      module_get_symbol(

        module,

        t_strdup_printf("%s_unload", module->name));

    if (unload_func != NULL)

      unload_func(svinst, plugin->context);

    plugin = plugin->next;

  }

  /* Physically unload modules */

  i_assert(sieve_modules_refcount > 0);

  if (--sieve_modules_refcount != 0)

    return;

  module_dir_unload(&sieve_modules);

}