constr_TYPE.h

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/*-
 * Copyright (c) 2003, 2004, 2005, 2006 Lev Walkin <vlm@lionet.info>.
 * All rights reserved.
 * Redistribution and modifications are permitted subject to BSD license.
 */
/*
 * This file contains the declaration structure called "ASN.1 Type Definition",
 * which holds all information necessary for encoding and decoding routines.
 * This structure even contains pointer to these encoding and decoding routines
 * for each defined ASN.1 type.
 */
#ifndef _CONSTR_TYPE_H_
#define _CONSTR_TYPE_H_

#include <ber_tlv_length.h>
#include <ber_tlv_tag.h>

#ifdef __cplusplus
extern "C" {
#endif

struct asn_TYPE_descriptor_s;   /* Forward declaration */
struct asn_TYPE_member_s;   /* Forward declaration */

/*
 * This type provides the context information for various ASN.1 routines,
 * primarily ones doing decoding. A member _asn_ctx of this type must be
 * included into certain target language's structures, such as compound types.
 */
typedef struct asn_struct_ctx_s {
    short phase;        /* Decoding phase */
    short step;     /* Elementary step of a phase */
    int context;        /* Other context information */
    void *ptr;      /* Decoder-specific stuff (stack elements) */
    ber_tlv_len_t left; /* Number of bytes left, -1 for indefinite */
} asn_struct_ctx_t;

#include <ber_decoder.h>    /* Basic Encoding Rules decoder */
#include <der_encoder.h>    /* Distinguished Encoding Rules encoder */
#include <xer_decoder.h>    /* Decoder of XER (XML, text) */
#include <xer_encoder.h>    /* Encoder into XER (XML, text) */
#include <per_decoder.h>    /* Packet Encoding Rules decoder */
#include <per_encoder.h>    /* Packet Encoding Rules encoder */
#include <constraints.h>    /* Subtype constraints support */

/*
 * Free the structure according to its specification.
 * If (free_contents_only) is set, the wrapper structure itself (struct_ptr)
 * will not be freed. (It may be useful in case the structure is allocated
 * statically or arranged on the stack, yet its elements are allocated
 * dynamically.)
 */
typedef void (asn_struct_free_f)(
        struct asn_TYPE_descriptor_s *type_descriptor,
        void *struct_ptr, int free_contents_only);
#define ASN_STRUCT_FREE(asn_DEF, ptr)   (asn_DEF).free_struct(&(asn_DEF),ptr,0)
#define ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF, ptr) \
                    (asn_DEF).free_struct(&(asn_DEF),ptr,1)

/*
 * Print the structure according to its specification.
 */
typedef int (asn_struct_print_f)(
        struct asn_TYPE_descriptor_s *type_descriptor,
        const void *struct_ptr,
        int level,  /* Indentation level */
        asn_app_consume_bytes_f *callback, void *app_key);

/*
 * Return the outmost tag of the type.
 * If the type is untagged CHOICE, the dynamic operation is performed.
 * NOTE: This function pointer type is only useful internally.
 * Do not use it in your application.
 */
typedef ber_tlv_tag_t (asn_outmost_tag_f)(
        struct asn_TYPE_descriptor_s *type_descriptor,
        const void *struct_ptr, int tag_mode, ber_tlv_tag_t tag);
/* The instance of the above function type; used internally. */
asn_outmost_tag_f asn_TYPE_outmost_tag;


/*
 * The definitive description of the destination language's structure.
 */
typedef struct asn_TYPE_descriptor_s {
    char *name; /* A name of the ASN.1 type. "" in some cases. */
    char *xml_tag;  /* Name used in XML tag */

    /*
     * Generalized functions for dealing with the specific type.
     * May be directly invoked by applications.
     */
    asn_struct_free_f  *free_struct;    /* Free the structure */
    asn_struct_print_f *print_struct;   /* Human readable output */
    asn_constr_check_f *check_constraints;  /* Constraints validator */
    ber_type_decoder_f *ber_decoder;    /* Generic BER decoder */
    der_type_encoder_f *der_encoder;    /* Canonical DER encoder */
    xer_type_decoder_f *xer_decoder;    /* Generic XER decoder */
    xer_type_encoder_f *xer_encoder;    /* [Canonical] XER encoder */
    per_type_decoder_f *uper_decoder;   /* Unaligned PER decoder */
    per_type_encoder_f *uper_encoder;   /* Unaligned PER encoder */

    /***********************************************************************
     * Internally useful members. Not to be used by applications directly. *
     **********************************************************************/

    /*
     * Tags that are expected to occur.
     */
    asn_outmost_tag_f  *outmost_tag;    /* <optional, internal> */
    ber_tlv_tag_t *tags;    /* Effective tags sequence for this type */
    int tags_count;     /* Number of tags which are expected */
    ber_tlv_tag_t *all_tags;/* Every tag for BER/containment */
    int all_tags_count; /* Number of tags */

    asn_per_constraints_t *per_constraints; /* PER compiled constraints */

    /*
     * An ASN.1 production type members (members of SEQUENCE, SET, CHOICE).
     */
    struct asn_TYPE_member_s *elements;
    int elements_count;

    /*
     * Additional information describing the type, used by appropriate
     * functions above.
     */
    void *specifics;
} asn_TYPE_descriptor_t;

/*
 * This type describes an element of the constructed type,
 * i.e. SEQUENCE, SET, CHOICE, etc.
 */
  enum asn_TYPE_flags_e {
    ATF_NOFLAGS,
    ATF_POINTER = 0x01, /* Represented by the pointer */
    ATF_OPEN_TYPE   = 0x02  /* ANY type, without meaningful tag */
  };
typedef struct asn_TYPE_member_s {
    enum asn_TYPE_flags_e flags;    /* Element's presentation flags */
    int optional;   /* Following optional members, including current */
    int memb_offset;        /* Offset of the element */
    ber_tlv_tag_t tag;      /* Outmost (most immediate) tag */
    int tag_mode;       /* IMPLICIT/no/EXPLICIT tag at current level */
    asn_TYPE_descriptor_t *type;    /* Member type descriptor */
    asn_constr_check_f *memb_constraints;   /* Constraints validator */
    asn_per_constraints_t *per_constraints; /* PER compiled constraints */
    int (*default_value)(int setval, void **sptr);  /* DEFAULT <value> */
    char *name;         /* ASN.1 identifier of the element */
} asn_TYPE_member_t;

/*
 * BER tag to element number mapping.
 */
typedef struct asn_TYPE_tag2member_s {
    ber_tlv_tag_t el_tag;   /* Outmost tag of the member */
    int el_no;      /* Index of the associated member, base 0 */
    int toff_first;     /* First occurence of the el_tag, relative */
    int toff_last;      /* Last occurence of the el_tag, relatvie */
} asn_TYPE_tag2member_t;

/*
 * This function is a wrapper around (td)->print_struct, which prints out
 * the contents of the target language's structure (struct_ptr) into the
 * file pointer (stream) in human readable form.
 * RETURN VALUES:
 *   0: The structure is printed.
 *  -1: Problem dumping the structure.
 * (See also xer_fprint() in xer_encoder.h)
 */
int asn_fprint(FILE *stream,        /* Destination stream descriptor */
    asn_TYPE_descriptor_t *td,  /* ASN.1 type descriptor */
    const void *struct_ptr);    /* Structure to be printed */

#ifdef __cplusplus
}
#endif

#endif  /* _CONSTR_TYPE_H_ */