/* Copyright (c) Pigeonhole authors, see top-level COPYING file */

#include "lib.h"

#include "hash.h"

#include "str.h"

#include "array.h"

#include "settings.h"

#include "sieve-common.h"

#include "sieve-ast.h"

#include "sieve-binary.h"

#include "sieve-code.h"

#include "sieve-objects.h"

#include "sieve-match-types.h"

#include "sieve-commands.h"

#include "sieve-validator.h"

#include "sieve-generator.h"

#include "sieve-dump.h"

#include "sieve-interpreter.h"

#include "ext-variables-common.h"

#include "ext-variables-name.h"

#include "ext-variables-modifiers.h"

/*

 * Limits

 */

unsigned int

sieve_variables_get_max_scope_count(const struct sieve_extension *var_ext)

{

  const struct ext_variables_context *extctx =

    ext_variables_get_context(var_ext);

  return extctx->set->max_scope_count;

}

size_t sieve_variables_get_max_value_size(

  const struct sieve_extension *var_ext)

{

  const struct ext_variables_context *extctx =

    ext_variables_get_context(var_ext);

  return extctx->set->max_value_size;

}

/*

 * Extension configuration

 */

int ext_variables_load(const struct sieve_extension *ext, void **context_r)

{

  struct sieve_instance *svinst = ext->svinst;

  const struct ext_variables_settings *set;

  struct ext_variables_context *extctx;

  const char *error;

  if (settings_get(svinst->event, &ext_variables_setting_parser_info, 0,

       &set, &error) < 0) {

    e_error(svinst->event, "%s", error);

    return -1;

  }

  extctx = i_new(struct ext_variables_context, 1);

  extctx->set = set;

  *context_r = extctx;

  return 0;

}

void ext_variables_unload(const struct sieve_extension *ext)

{

  struct ext_variables_context *extctx = ext->context;

  if (extctx == NULL)

    return;

  settings_free(extctx->set);

  i_free(extctx);

}

const struct ext_variables_context *

ext_variables_get_context(const struct sieve_extension *var_ext)

{

  const struct ext_variables_context *extctx = var_ext->context;

  i_assert(var_ext->def == &variables_extension);

  return extctx;

}

/*

 * Variable scope

 */

struct sieve_variable_scope {

  pool_t pool;

  int refcount;

  struct sieve_instance *svinst;

  const struct sieve_extension *var_ext;

  const struct sieve_extension *ext;

  struct sieve_variable *error_var;

  HASH_TABLE(const char *, struct sieve_variable *) variables;

  ARRAY(struct sieve_variable *) variable_index;

};

struct sieve_variable_scope_binary {

  struct sieve_variable_scope *scope;

  unsigned int count;

  struct sieve_binary_block *sblock;

  sieve_size_t address;

};

struct sieve_variable_scope_iter {

  struct sieve_variable_scope *scope;

  struct hash_iterate_context *hctx;

};

struct sieve_variable_scope *

sieve_variable_scope_create(struct sieve_instance *svinst,

          const struct sieve_extension *var_ext,

          const struct sieve_extension *ext)

{

  struct sieve_variable_scope *scope;

  pool_t pool;

  i_assert(var_ext->def == &variables_extension);

  pool = pool_alloconly_create("sieve_variable_scope", 4096);

  scope = p_new(pool, struct sieve_variable_scope, 1);

  scope->pool = pool;

  scope->refcount = 1;

  scope->svinst = svinst;

  scope->var_ext = var_ext;

  scope->ext = ext;

  hash_table_create(&scope->variables, pool, 0, strcase_hash, strcasecmp);

  p_array_init(&scope->variable_index, pool, 128);

  return scope;

}

void sieve_variable_scope_ref(struct sieve_variable_scope *scope)

{

  scope->refcount++;

}

void sieve_variable_scope_unref(struct sieve_variable_scope **_scope)

{

  struct sieve_variable_scope *scope = *_scope;

  i_assert(scope->refcount > 0);

  if (--scope->refcount != 0)

    return;

  hash_table_destroy(&scope->variables);

  *_scope = NULL;

  pool_unref(&scope->pool);

}

pool_t sieve_variable_scope_pool(struct sieve_variable_scope *scope)

{

  return scope->pool;

}

struct sieve_variable *

sieve_variable_scope_declare(struct sieve_variable_scope *scope,

           const char *identifier)

{

  unsigned int max_scope_count;

  struct sieve_variable *var;

  var = hash_table_lookup(scope->variables, identifier);

  if (var != NULL)

    return var;

  max_scope_count = sieve_variables_get_max_scope_count(scope->var_ext);

  if (array_count(&scope->variable_index) >= max_scope_count) {

    if (scope->error_var == NULL) {

      var = p_new(scope->pool, struct sieve_variable, 1);

      var->identifier = "@ERROR@";

      var->index = 0;

      scope->error_var = var;

      return NULL;

    }

    return scope->error_var;

  }

  var = p_new(scope->pool, struct sieve_variable, 1);

  var->ext = scope->ext;

  var->identifier = p_strdup(scope->pool, identifier);

  var->index = array_count(&scope->variable_index);

  hash_table_insert(scope->variables, var->identifier, var);

  array_append(&scope->variable_index, &var, 1);

  return var;

}

struct sieve_variable *

sieve_variable_scope_get_variable(struct sieve_variable_scope *scope,

          const char *identifier)

{

  return hash_table_lookup(scope->variables, identifier);

}

struct sieve_variable *

sieve_variable_scope_import(struct sieve_variable_scope *scope,

          struct sieve_variable *var)

{

  struct sieve_variable *old_var, *new_var;

  old_var = sieve_variable_scope_get_variable(scope, var->identifier);

  if (old_var != NULL) {

    i_assert(memcmp(old_var, var, sizeof(*var)) == 0);

    return old_var;

  }

  new_var = p_new(scope->pool, struct sieve_variable, 1);

  memcpy(new_var, var, sizeof(*new_var));

  hash_table_insert(scope->variables, new_var->identifier, new_var);

  /* Not entered into the index because it is an external variable

     (This can be done unlimited; only limited by the size of the external

     scope)

   */

  return new_var;

}

struct sieve_variable_scope_iter *

sieve_variable_scope_iterate_init(struct sieve_variable_scope *scope)

{

  struct sieve_variable_scope_iter *iter;

  iter = t_new(struct sieve_variable_scope_iter, 1);

  iter->scope = scope;

  iter->hctx = hash_table_iterate_init(scope->variables);

  return iter;

}

bool sieve_variable_scope_iterate(struct sieve_variable_scope_iter *iter,

          struct sieve_variable **var_r)

{

  const char *key;

  return hash_table_iterate(iter->hctx, iter->scope->variables,

          &key, var_r);

}

void sieve_variable_scope_iterate_deinit(

  struct sieve_variable_scope_iter **iter)

{

  hash_table_iterate_deinit(&(*iter)->hctx);

  *iter = NULL;

}

unsigned int

sieve_variable_scope_declarations(struct sieve_variable_scope *scope)

{

  return hash_table_count(scope->variables);

}

unsigned int sieve_variable_scope_size(struct sieve_variable_scope *scope)

{

  return array_count(&scope->variable_index);

}

struct sieve_variable *const *

sieve_variable_scope_get_variables(struct sieve_variable_scope *scope,

           unsigned int *size_r)

{

  return array_get(&scope->variable_index, size_r);

}

struct sieve_variable *

sieve_variable_scope_get_indexed(struct sieve_variable_scope *scope,

         unsigned int index)

{

  struct sieve_variable *const *var;

  if (index >= array_count(&scope->variable_index))

    return NULL;

  var = array_idx(&scope->variable_index, index);

  return *var;

}

/* Scope binary */

struct sieve_variable_scope *

sieve_variable_scope_binary_dump(struct sieve_instance *svinst,

         const struct sieve_extension *var_ext,

         const struct sieve_extension *ext,

         const struct sieve_dumptime_env *denv,

         sieve_size_t *address)

{

  struct sieve_variable_scope *local_scope;

  unsigned int i, scope_size;

  sieve_size_t pc;

  sieve_offset_t end_offset;

  /* Read scope size */

  sieve_code_mark(denv);

  if (!sieve_binary_read_unsigned(denv->sblock, address, &scope_size))

    return NULL;

  /* Read offset */

  pc = *address;

  if (!sieve_binary_read_offset(denv->sblock, address, &end_offset))

    return NULL;

  /* Create scope */

  local_scope = sieve_variable_scope_create(svinst, var_ext, ext);

  /* Read and dump scope itself */

  sieve_code_dumpf(denv, "VARIABLES SCOPE [%u] (end: %08x)",

       scope_size, (unsigned int)(pc + end_offset));

  for (i = 0; i < scope_size; i++) {

    string_t *identifier;

    sieve_code_mark(denv);

    if (!sieve_binary_read_string(denv->sblock, address,

                &identifier))

      return NULL;

    sieve_code_dumpf(denv, "%3d: '%s'", i, str_c(identifier));

    (void)sieve_variable_scope_declare(local_scope,

               str_c(identifier));

  }

  return local_scope;

}

struct sieve_variable_scope_binary *

sieve_variable_scope_binary_create(struct sieve_variable_scope *scope)

{

  struct sieve_variable_scope_binary *scpbin;

  scpbin = p_new(scope->pool, struct sieve_variable_scope_binary, 1);

  scpbin->scope = scope;

  return scpbin;

}

void sieve_variable_scope_binary_ref(struct sieve_variable_scope_binary *scpbin)

{

  sieve_variable_scope_ref(scpbin->scope);

}

void sieve_variable_scope_binary_unref(

  struct sieve_variable_scope_binary **scpbin)

{

  sieve_variable_scope_unref(&(*scpbin)->scope);

  *scpbin = NULL;

}

struct sieve_variable_scope_binary *

sieve_variable_scope_binary_read(struct sieve_instance *svinst,

         const struct sieve_extension *var_ext,

         const struct sieve_extension *ext,

         struct sieve_binary_block *sblock,

         sieve_size_t *address)

{

  struct sieve_variable_scope *scope;

  struct sieve_variable_scope_binary *scpbin;

  unsigned int scope_count, max_scope_count;

  const char *ext_name = (ext == NULL ? "variables" :

        sieve_extension_name(ext));

  sieve_size_t pc;

  sieve_offset_t end_offset;

  /* Read scope size */

  if (!sieve_binary_read_unsigned(sblock, address, &scope_count)) {

    e_error(svinst->event, "%s: "

      "variable scope: failed to read count", ext_name);

    return NULL;

  }

  /* Check size limit */

  max_scope_count = sieve_variables_get_max_scope_count(var_ext);

  if (scope_count > max_scope_count) {

    e_error(svinst->event, "%s: "

      "variable scope: count exceeds the limit (%u > %u)",

      ext_name, scope_count, max_scope_count);

    return NULL;

  }

  /* Read offset */

  pc = *address;

  if (!sieve_binary_read_offset(sblock, address, &end_offset)) {

    e_error(svinst->event, "%s: "

      "variable scope: failed to read end offset", ext_name);

    return NULL;

  }

  /* Create scope */

  scope = sieve_variable_scope_create(svinst, var_ext, ext);

  scpbin = sieve_variable_scope_binary_create(scope);

  scpbin->count = scope_count;

  scpbin->sblock = sblock;

  scpbin->address = *address;

  *address = pc + end_offset;

  return scpbin;

}

struct sieve_variable_scope *

sieve_variable_scope_binary_get(struct sieve_variable_scope_binary *scpbin)

{

  const struct sieve_extension *ext = scpbin->scope->ext;

  struct sieve_instance *svinst = scpbin->scope->svinst;

  const char *ext_name = (ext == NULL ? "variables" :

        sieve_extension_name(ext));

  unsigned int i;

  if (scpbin->sblock != NULL) {

    sieve_size_t *address = &scpbin->address;

    /* Read scope itself */

    for (i = 0; i < scpbin->count; i++) {

      struct sieve_variable *var;

      string_t *identifier;

      if (!sieve_binary_read_string(scpbin->sblock, address,

                  &identifier)) {

        e_error(svinst->event, "%s: variable scope: "

          "failed to read variable name",

          ext_name);

        return NULL;

      }

      var = sieve_variable_scope_declare(scpbin->scope,

                 str_c(identifier));

      i_assert(var != NULL);

      i_assert(var->index == i);

    }

    scpbin->sblock = NULL;

  }

  return scpbin->scope;

}

unsigned int

sieve_variable_scope_binary_get_count(

  struct sieve_variable_scope_binary *scpbin)

{

  if (scpbin->sblock != NULL)

    return scpbin->count;

  return array_count(&scpbin->scope->variable_index);

}

/*

 * Variable storage

 */

struct sieve_variable_storage {

  pool_t pool;

  const struct sieve_extension *var_ext;

  struct sieve_variable_scope *scope;

  struct sieve_variable_scope_binary *scope_bin;

  unsigned int max_count;

  ARRAY(string_t *) var_values;

};

struct sieve_variable_storage *

sieve_variable_storage_create(const struct sieve_extension *var_ext,

            pool_t pool,

            struct sieve_variable_scope_binary *scpbin)

{

  struct sieve_variable_storage *storage;

  storage = p_new(pool, struct sieve_variable_storage, 1);

  storage->pool = pool;

  storage->var_ext = var_ext;

  storage->scope_bin = scpbin;

  storage->scope = NULL;

  storage->max_count = sieve_variable_scope_binary_get_count(scpbin);

  p_array_init(&storage->var_values, pool, 4);

  return storage;

}

static inline bool

sieve_variable_valid(struct sieve_variable_storage *storage,

         unsigned int index)

{

  if (storage->scope_bin == NULL)

    return TRUE;

  return (index < storage->max_count);

}

bool sieve_variable_get_identifier(struct sieve_variable_storage *storage,

           unsigned int index, const char **identifier)

{

  struct sieve_variable *const *var;

  *identifier = NULL;

  if (storage->scope_bin == NULL)

    return TRUE;

  if (storage->scope == NULL) {

    storage->scope =

      sieve_variable_scope_binary_get(storage->scope_bin);

    if (storage->scope == NULL)

      return FALSE;

  }

  /* FIXME: direct invasion of the scope object is a bit ugly */

  if (index >= array_count(&storage->scope->variable_index))

    return FALSE;

  var = array_idx(&storage->scope->variable_index, index);

  if (*var != NULL)

    *identifier = (*var)->identifier;

  return TRUE;

}

const char *

sieve_variable_get_varid(struct sieve_variable_storage *storage,

       unsigned int index)

{

  if (storage->scope_bin == NULL)

    return t_strdup_printf("%ld", (long)index);

  if (storage->scope == NULL) {

    storage->scope =

      sieve_variable_scope_binary_get(storage->scope_bin);

    if (storage->scope == NULL)

      return NULL;

  }

  return sieve_ext_variables_get_varid(storage->scope->ext, index);

}

bool sieve_variable_get(struct sieve_variable_storage *storage,

      unsigned int index, string_t **value)

{

  *value = NULL;

  if (index < array_count(&storage->var_values)) {

    string_t *const *varent;

    varent = array_idx(&storage->var_values, index);

    *value = *varent;

  } else if (!sieve_variable_valid(storage, index)) {

    return FALSE;

  }

  return TRUE;

}

bool sieve_variable_get_modifiable(struct sieve_variable_storage *storage,

           unsigned int index, string_t **value)

{

  string_t *dummy;

  if (value == NULL)

    value = &dummy;

  if (!sieve_variable_get(storage, index, value))

    return FALSE;

  if (*value == NULL) {

    *value = str_new(storage->pool, 256);

    array_idx_set(&storage->var_values, index, value);

  }

  return TRUE;

}

bool sieve_variable_assign(struct sieve_variable_storage *storage,

         unsigned int index, const string_t *value)

{

  const struct ext_variables_context *extctx =

    ext_variables_get_context(storage->var_ext);

  string_t *varval;

  if (!sieve_variable_get_modifiable(storage, index, &varval))

    return FALSE;

  str_truncate(varval, 0);

  str_append_str(varval, value);

  /* Just a precaution, caller should prevent this in the first place */

  if (str_len(varval) > extctx->set->max_value_size)

    str_truncate_utf8(varval, extctx->set->max_value_size);

  return TRUE;

}

bool sieve_variable_assign_cstr(struct sieve_variable_storage *storage,

        unsigned int index, const char *value)

{

  const struct ext_variables_context *extctx =

    ext_variables_get_context(storage->var_ext);

  string_t *varval;

  if (!sieve_variable_get_modifiable(storage, index, &varval))

    return FALSE;

  str_truncate(varval, 0);

  str_append(varval, value);

  /* Just a precaution, caller should prevent this in the first place */

  if (str_len(varval) > extctx->set->max_value_size)

    str_truncate_utf8(varval, extctx->set->max_value_size);

  return TRUE;

}

/*

 * AST Context

 */

static void

ext_variables_ast_free(const struct sieve_extension *ext ATTR_UNUSED,

           struct sieve_ast *ast ATTR_UNUSED, void *context)

{

  struct sieve_variable_scope *local_scope =

    (struct sieve_variable_scope *)context;

  /* Unreference main variable scope */

  sieve_variable_scope_unref(&local_scope);

}

static const struct sieve_ast_extension variables_ast_extension = {

  &variables_extension,

  ext_variables_ast_free,

};

static struct sieve_variable_scope *

ext_variables_create_local_scope(const struct sieve_extension *this_ext,

         struct sieve_ast *ast)

{

  struct sieve_variable_scope *scope;

  scope = sieve_variable_scope_create(this_ext->svinst, this_ext, NULL);

  sieve_ast_extension_register(ast, this_ext, &variables_ast_extension,

             scope);

  return scope;

}

static struct sieve_variable_scope *

ext_variables_ast_get_local_scope(const struct sieve_extension *this_ext,

          struct sieve_ast *ast)

{

  struct sieve_variable_scope *local_scope =

    (struct sieve_variable_scope *)

      sieve_ast_extension_get_context(ast, this_ext);

  return local_scope;

}

/*

 * Validator context

 */

static struct ext_variables_validator_context *

ext_variables_validator_context_create(const struct sieve_extension *this_ext,

               struct sieve_validator *valdtr)

{

  pool_t pool = sieve_validator_pool(valdtr);

  struct ext_variables_validator_context *ctx;

  struct sieve_ast *ast = sieve_validator_ast(valdtr);

  ctx = p_new(pool, struct ext_variables_validator_context, 1);

  ctx->modifiers = sieve_validator_object_registry_create(valdtr);

  ctx->namespaces = sieve_validator_object_registry_create(valdtr);

  ctx->local_scope = ext_variables_create_local_scope(this_ext, ast);

  sieve_validator_extension_set_context(valdtr, this_ext, ctx);

  return ctx;

}

struct ext_variables_validator_context *

ext_variables_validator_context_get(const struct sieve_extension *this_ext,

            struct sieve_validator *valdtr)

{

  struct ext_variables_validator_context *ctx;

  i_assert(sieve_extension_is(this_ext, variables_extension));

  ctx = (struct ext_variables_validator_context *)

    sieve_validator_extension_get_context(valdtr, this_ext);

  if (ctx == NULL)

    ctx = ext_variables_validator_context_create(this_ext, valdtr);

  return ctx;

}

void ext_variables_validator_initialize(const struct sieve_extension *this_ext,

          struct sieve_validator *valdtr)

{

  struct ext_variables_validator_context *ctx;

  /* Create our context */

  ctx = ext_variables_validator_context_get(this_ext, valdtr);

  ext_variables_register_core_modifiers(this_ext, ctx);

  ctx->active = TRUE;

}

struct sieve_variable *ext_variables_validator_get_variable(

  const struct sieve_extension *this_ext,

  struct sieve_validator *validator, const char *variable)

{

  struct ext_variables_validator_context *ctx =

    ext_variables_validator_context_get(this_ext, validator);

  return sieve_variable_scope_get_variable(ctx->local_scope, variable);

}

struct sieve_variable *

ext_variables_validator_declare_variable(const struct sieve_extension *this_ext,

           struct sieve_validator *validator,

           const char *variable)

{

  struct ext_variables_validator_context *ctx =

    ext_variables_validator_context_get(this_ext, validator);

  return sieve_variable_scope_declare(ctx->local_scope, variable);

}

struct sieve_variable_scope *

sieve_ext_variables_get_local_scope(const struct sieve_extension *var_ext,

            struct sieve_validator *validator)

{

  struct ext_variables_validator_context *ctx =

    ext_variables_validator_context_get(var_ext, validator);

  return ctx->local_scope;

}

bool sieve_ext_variables_is_active(const struct sieve_extension *var_ext,

           struct sieve_validator *valdtr)

{

  struct ext_variables_validator_context *ctx =

    ext_variables_validator_context_get(var_ext, valdtr);

  return (ctx != NULL && ctx->active);

}

/*

 * Code generation

 */

bool ext_variables_generator_load(const struct sieve_extension *ext,

          const struct sieve_codegen_env *cgenv)

{

  struct sieve_variable_scope *local_scope =

    ext_variables_ast_get_local_scope(ext, cgenv->ast);

  unsigned int count = sieve_variable_scope_size(local_scope);

  sieve_size_t jump;

  sieve_binary_emit_unsigned(cgenv->sblock, count);

  jump = sieve_binary_emit_offset(cgenv->sblock, 0);

  if (count > 0) {

    unsigned int size, i;

    struct sieve_variable *const *vars =

      sieve_variable_scope_get_variables(local_scope, &size);

    for (i = 0; i < size; i++) {

      sieve_binary_emit_cstring(cgenv->sblock,

              vars[i]->identifier);

    }

  }

  sieve_binary_resolve_offset(cgenv->sblock, jump);

  return TRUE;

}

/*

 * Interpreter context

 */

struct ext_variables_interpreter_context {

  pool_t pool;

  struct sieve_variable_scope *local_scope;

  struct sieve_variable_scope_binary *local_scope_bin;

  struct sieve_variable_storage *local_storage;

  ARRAY(struct sieve_variable_storage *) ext_storages;

};

static void

ext_variables_interpreter_free(const struct sieve_extension *ext ATTR_UNUSED,

             struct sieve_interpreter *interp ATTR_UNUSED,

             void *context)

{

  struct ext_variables_interpreter_context *ctx =

    (struct ext_variables_interpreter_context *)context;

  sieve_variable_scope_binary_unref(&ctx->local_scope_bin);

}

static struct sieve_interpreter_extension

variables_interpreter_extension = {

  .ext_def = &variables_extension,

  .free = ext_variables_interpreter_free,

};

static struct ext_variables_interpreter_context *

ext_variables_interpreter_context_create(

  const struct sieve_extension *this_ext,

  struct sieve_interpreter *interp,

  struct sieve_variable_scope_binary *scpbin)

{

  pool_t pool = sieve_interpreter_pool(interp);

  struct ext_variables_interpreter_context *ctx;

  ctx = p_new(pool, struct ext_variables_interpreter_context, 1);

  ctx->pool = pool;

  ctx->local_scope = NULL;

  ctx->local_scope_bin = scpbin;

  ctx->local_storage =

    sieve_variable_storage_create(this_ext, pool, scpbin);

  p_array_init(&ctx->ext_storages, pool,

         sieve_extensions_get_count(this_ext->svinst));

  sieve_interpreter_extension_register(interp, this_ext,

               &variables_interpreter_extension,

               ctx);

  return ctx;

}

bool ext_variables_interpreter_load(const struct sieve_extension *ext,

            const struct sieve_runtime_env *renv,

            sieve_size_t *address)

{

  const struct sieve_execute_env *eenv = renv->exec_env;

  struct sieve_variable_scope_binary *scpbin;

  scpbin = sieve_variable_scope_binary_read(eenv->svinst, ext, NULL,

              renv->sblock, address);

  if (scpbin == NULL)

    return FALSE;

  /* Create our context */

  (void)ext_variables_interpreter_context_create(ext, renv->interp,

                   scpbin);

  /* Enable support for match values */

  (void)sieve_match_values_set_enabled(renv, TRUE);

  return TRUE;

}

static inline struct ext_variables_interpreter_context *

ext_variables_interpreter_context_get(const struct sieve_extension *this_ext,

              struct sieve_interpreter *interp)

{

  struct ext_variables_interpreter_context *ctx;

  i_assert(sieve_extension_is(this_ext, variables_extension));

  ctx = (struct ext_variables_interpreter_context *)

    sieve_interpreter_extension_get_context(interp, this_ext);

  return ctx;

}

struct sieve_variable_storage *

sieve_ext_variables_runtime_get_storage(const struct sieve_extension *var_ext,

          const struct sieve_runtime_env *renv,

          const struct sieve_extension *ext)

{

  struct ext_variables_interpreter_context *ctx =

    ext_variables_interpreter_context_get(var_ext, renv->interp);

  struct sieve_variable_storage *const *storage;

  if (ext == NULL)

    return ctx->local_storage;

  if (ext->id >= (int)array_count(&ctx->ext_storages))

    storage = NULL;

  else

    storage = array_idx(&ctx->ext_storages, ext->id);

  if (storage == NULL)

    return NULL;

  return *storage;

}

void sieve_ext_variables_runtime_set_storage(

  const struct sieve_extension *var_ext,

  const struct sieve_runtime_env *renv, const struct sieve_extension *ext,

  struct sieve_variable_storage *storage)

{

  struct ext_variables_interpreter_context *ctx =

    ext_variables_interpreter_context_get(var_ext, renv->interp);

  if (ctx == NULL || ext == NULL || storage == NULL)

    return;

  if (ext->id < 0)

    return;

  array_idx_set(&ctx->ext_storages, (unsigned int) ext->id, &storage);

}