SIEVEARGS (sieve_ast)

typedef struct sieve_ast AST;
typedef struct _token_value SIEVETOKEN;

struct sieve_ast {
  int op;
  AST *next;
  AST **args;
  int nargs;  /* number of actual args */
  int margs;  /* number of arg slots */
  SIEVETOKEN value;
  ec_atomic_t refcount;
};
struct _token_value {
  enum { TV_VOID, TV_NUMBER, TV_STRING, TV_AST, TV_ACT, TV_HASH, TV_TAG } type;
  union {
    /* RFC3028: all numbers are unsigned and MUST provide
     * at least 31 bits */
    int32_t number;
    string str;
    AST *ast;
    sieve_extension_action *act;
    ec_hash_table *hash;
  } v;
  sieve_accelerator a;
  int lineno;
};
typedef struct _sieve_accelerator {
  enum { TAC_NONE, TAC_PCRE, TAC_USER, TAC_AHO } type;
  int can_accel;
  union {
    ec_pcre_elt *pcre_work;
    void *userdata;
    struct {
      ac_automaton_t *machine;
      ec_hash_table *by_len;
    } aho_work;
  } work;
} sieve_accelerator;