constr_SET_OF.c

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/*-
 * Copyright (c) 2003, 2004, 2005 Lev Walkin <vlm@lionet.info>.
 * All rights reserved.
 * Redistribution and modifications are permitted subject to BSD license.
 */
#include <asn_internal.h>
#include <constr_SET_OF.h>
#include <asn_SET_OF.h>

/*
 * Number of bytes left for this structure.
 * (ctx->left) indicates the number of bytes _transferred_ for the structure.
 * (size) contains the number of bytes in the buffer passed.
 */
#define LEFT    ((size<(size_t)ctx->left)?size:(size_t)ctx->left)

/*
 * If the subprocessor function returns with an indication that it wants
 * more data, it may well be a fatal decoding problem, because the
 * size is constrained by the <TLV>'s L, even if the buffer size allows
 * reading more data.
 * For example, consider the buffer containing the following TLVs:
 * <T:5><L:1><V> <T:6>...
 * The TLV length clearly indicates that one byte is expected in V, but
 * if the V processor returns with "want more data" even if the buffer
 * contains way more data than the V processor have seen.
 */
#define SIZE_VIOLATION  (ctx->left >= 0 && (size_t)ctx->left <= size)

/*
 * This macro "eats" the part of the buffer which is definitely "consumed",
 * i.e. was correctly converted into local representation or rightfully skipped.
 */
#undef  ADVANCE
#define ADVANCE(num_bytes)  do {        \
        size_t num = num_bytes;     \
        ptr = ((const char *)ptr) + num;\
        size -= num;            \
        if(ctx->left >= 0)      \
            ctx->left -= num;   \
        consumed_myself += num;     \
    } while(0)

/*
 * Switch to the next phase of parsing.
 */
#undef  NEXT_PHASE
#undef  PHASE_OUT
#define NEXT_PHASE(ctx) do {            \
        ctx->phase++;           \
        ctx->step = 0;          \
    } while(0)
#define PHASE_OUT(ctx)  do { ctx->phase = 10; } while(0)

/*
 * Return a standardized complex structure.
 */
#undef  RETURN
#define RETURN(_code)   do {            \
        rval.code = _code;      \
        rval.consumed = consumed_myself;\
        return rval;            \
    } while(0)

/*
 * The decoder of the SET OF type.
 */
asn_dec_rval_t
SET_OF_decode_ber(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
    void **struct_ptr, const void *ptr, size_t size, int tag_mode) {
    /*
     * Bring closer parts of structure description.
     */
    asn_SET_OF_specifics_t *specs = (asn_SET_OF_specifics_t *)td->specifics;
    asn_TYPE_member_t *elm = td->elements;  /* Single one */

    /*
     * Parts of the structure being constructed.
     */
    void *st = *struct_ptr; /* Target structure. */
    asn_struct_ctx_t *ctx;  /* Decoder context */

    ber_tlv_tag_t tlv_tag;  /* T from TLV */
    asn_dec_rval_t rval;    /* Return code from subparsers */

    ssize_t consumed_myself = 0;    /* Consumed bytes from ptr */

    ASN_DEBUG("Decoding %s as SET OF", td->name);
    
    /*
     * Create the target structure if it is not present already.
     */
    if(st == 0) {
        st = *struct_ptr = CALLOC(1, specs->struct_size);
        if(st == 0) {
            RETURN(RC_FAIL);
        }
    }

    /*
     * Restore parsing context.
     */
    ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);
    
    /*
     * Start to parse where left previously
     */
    switch(ctx->phase) {
    case 0:
        /*
         * PHASE 0.
         * Check that the set of tags associated with given structure
         * perfectly fits our expectations.
         */

        rval = ber_check_tags(opt_codec_ctx, td, ctx, ptr, size,
            tag_mode, 1, &ctx->left, 0);
        if(rval.code != RC_OK) {
            ASN_DEBUG("%s tagging check failed: %d",
                td->name, rval.code);
            return rval;
        }

        if(ctx->left >= 0)
            ctx->left += rval.consumed; /* ?Substracted below! */
        ADVANCE(rval.consumed);

        ASN_DEBUG("Structure consumes %ld bytes, "
            "buffer %ld", (long)ctx->left, (long)size);

        NEXT_PHASE(ctx);
        /* Fall through */
    case 1:
        /*
         * PHASE 1.
         * From the place where we've left it previously,
         * try to decode the next item.
         */
      for(;; ctx->step = 0) {
        ssize_t tag_len;    /* Length of TLV's T */

        if(ctx->step & 1)
            goto microphase2;

        /*
         * MICROPHASE 1: Synchronize decoding.
         */

        if(ctx->left == 0) {
            ASN_DEBUG("End of SET OF %s", td->name);
            /*
             * No more things to decode.
             * Exit out of here.
             */
            PHASE_OUT(ctx);
            RETURN(RC_OK);
        }

        /*
         * Fetch the T from TLV.
         */
        tag_len = ber_fetch_tag(ptr, LEFT, &tlv_tag);
        switch(tag_len) {
        case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
            /* Fall through */
        case -1: RETURN(RC_FAIL);
        }

        if(ctx->left < 0 && ((const uint8_t *)ptr)[0] == 0) {
            if(LEFT < 2) {
                if(SIZE_VIOLATION)
                    RETURN(RC_FAIL);
                else
                    RETURN(RC_WMORE);
            } else if(((const uint8_t *)ptr)[1] == 0) {
                /*
                 * Found the terminator of the
                 * indefinite length structure.
                 */
                break;
            }
        }

        /* Outmost tag may be unknown and cannot be fetched/compared */
        if(elm->tag != (ber_tlv_tag_t)-1) {
            if(BER_TAGS_EQUAL(tlv_tag, elm->tag)) {
            /*
             * The new list member of expected type has arrived.
             */
            } else {
            ASN_DEBUG("Unexpected tag %s fixed SET OF %s",
                ber_tlv_tag_string(tlv_tag), td->name);
            ASN_DEBUG("%s SET OF has tag %s",
                td->name, ber_tlv_tag_string(elm->tag));
            RETURN(RC_FAIL);
            }
        }

        /*
         * MICROPHASE 2: Invoke the member-specific decoder.
         */
        ctx->step |= 1;     /* Confirm entering next microphase */
    microphase2:
        
        /*
         * Invoke the member fetch routine according to member's type
         */
        rval = elm->type->ber_decoder(opt_codec_ctx,
                elm->type, &ctx->ptr, ptr, LEFT, 0);
        ASN_DEBUG("In %s SET OF %s code %d consumed %d",
            td->name, elm->type->name,
            rval.code, (int)rval.consumed);
        switch(rval.code) {
        case RC_OK:
            {
                asn_anonymous_set_ *list = _A_SET_FROM_VOID(st);
                if(ASN_SET_ADD(list, ctx->ptr) != 0)
                    RETURN(RC_FAIL);
                else
                    ctx->ptr = 0;
            }
            break;
        case RC_WMORE: /* More data expected */
            if(!SIZE_VIOLATION) {
                ADVANCE(rval.consumed);
                RETURN(RC_WMORE);
            }
            /* Fall through */
        case RC_FAIL: /* Fatal error */
            ASN_STRUCT_FREE(*elm->type, ctx->ptr);
            ctx->ptr = 0;
            RETURN(RC_FAIL);
        } /* switch(rval) */
        
        ADVANCE(rval.consumed);
      } /* for(all list members) */

        NEXT_PHASE(ctx);
    case 2:
        /*
         * Read in all "end of content" TLVs.
         */
        while(ctx->left < 0) {
            if(LEFT < 2) {
                if(LEFT > 0 && ((const char *)ptr)[0] != 0) {
                    /* Unexpected tag */
                    RETURN(RC_FAIL);
                } else {
                    RETURN(RC_WMORE);
                }
            }
            if(((const char *)ptr)[0] == 0
            && ((const char *)ptr)[1] == 0) {
                ADVANCE(2);
                ctx->left++;
            } else {
                RETURN(RC_FAIL);
            }
        }

        PHASE_OUT(ctx);
    }
    
    RETURN(RC_OK);
}

/*
 * Internally visible buffer holding a single encoded element.
 */
struct _el_buffer {
    uint8_t *buf;
    size_t length;
    size_t size;
};
/* Append bytes to the above structure */
static int _el_addbytes(const void *buffer, size_t size, void *el_buf_ptr) {
    struct _el_buffer *el_buf = (struct _el_buffer *)el_buf_ptr;

    if(el_buf->length + size > el_buf->size)
        return -1;

    memcpy(el_buf->buf + el_buf->length, buffer, size);

    el_buf->length += size;
    return 0;
}
static int _el_buf_cmp(const void *ap, const void *bp) {
    const struct _el_buffer *a = (const struct _el_buffer *)ap;
    const struct _el_buffer *b = (const struct _el_buffer *)bp;
    int ret;
    size_t common_len;

    if(a->length < b->length)
        common_len = a->length;
    else
        common_len = b->length;

    ret = memcmp(a->buf, b->buf, common_len);
    if(ret == 0) {
        if(a->length < b->length)
            ret = -1;
        else if(a->length > b->length)
            ret = 1;
    }

    return ret;
}

/*
 * The DER encoder of the SET OF type.
 */
asn_enc_rval_t
SET_OF_encode_der(asn_TYPE_descriptor_t *td, void *ptr,
    int tag_mode, ber_tlv_tag_t tag,
    asn_app_consume_bytes_f *cb, void *app_key) {
    asn_TYPE_member_t *elm = td->elements;
    asn_TYPE_descriptor_t *elm_type = elm->type;
    der_type_encoder_f *der_encoder = elm_type->der_encoder;
    asn_anonymous_set_ *list = _A_SET_FROM_VOID(ptr);
    size_t computed_size = 0;
    ssize_t encoding_size = 0;
    struct _el_buffer *encoded_els;
    ssize_t eels_count = 0;
    size_t max_encoded_len = 1;
    asn_enc_rval_t erval;
    int ret;
    int edx;

    ASN_DEBUG("Estimating size for SET OF %s", td->name);

    /*
     * Gather the length of the underlying members sequence.
     */
    for(edx = 0; edx < list->count; edx++) {
        void *memb_ptr = list->array[edx];
        if(!memb_ptr) continue;
        erval = der_encoder(elm_type, memb_ptr, 0, elm->tag, 0, 0);
        if(erval.encoded == -1)
            return erval;
        computed_size += erval.encoded;

        /* Compute maximum encoding's size */
        if(max_encoded_len < (size_t)erval.encoded)
            max_encoded_len = erval.encoded;
    }

    /*
     * Encode the TLV for the sequence itself.
     */
    encoding_size = der_write_tags(td, computed_size, tag_mode, 1, tag,
        cb, app_key);
    if(encoding_size == -1) {
        erval.encoded = -1;
        erval.failed_type = td;
        erval.structure_ptr = ptr;
        return erval;
    }
    computed_size += encoding_size;

    if(!cb || list->count == 0) {
        erval.encoded = computed_size;
        _ASN_ENCODED_OK(erval);
    }

    /*
     * DER mandates dynamic sorting of the SET OF elements
     * according to their encodings. Build an array of the
     * encoded elements.
     */
    encoded_els = (struct _el_buffer *)MALLOC(
                list->count * sizeof(encoded_els[0]));
    if(encoded_els == NULL) {
        erval.encoded = -1;
        erval.failed_type = td;
        erval.structure_ptr = ptr;
        return erval;
    }

    ASN_DEBUG("Encoding members of %s SET OF", td->name);

    /*
     * Encode all members.
     */
    for(edx = 0; edx < list->count; edx++) {
        void *memb_ptr = list->array[edx];
        struct _el_buffer *encoded_el = &encoded_els[eels_count];

        if(!memb_ptr) continue;

        /*
         * Prepare space for encoding.
         */
        encoded_el->buf = (uint8_t *)MALLOC(max_encoded_len);
        if(encoded_el->buf) {
            encoded_el->length = 0;
            encoded_el->size = max_encoded_len;
        } else {
            for(edx--; edx >= 0; edx--)
                FREEMEM(encoded_els[edx].buf);
            FREEMEM(encoded_els);
            erval.encoded = -1;
            erval.failed_type = td;
            erval.structure_ptr = ptr;
            return erval;
        }

        /*
         * Encode the member into the prepared space.
         */
        erval = der_encoder(elm_type, memb_ptr, 0, elm->tag,
            _el_addbytes, encoded_el);
        if(erval.encoded == -1) {
            for(; edx >= 0; edx--)
                FREEMEM(encoded_els[edx].buf);
            FREEMEM(encoded_els);
            return erval;
        }
        encoding_size += erval.encoded;
        eels_count++;
    }

    /*
     * Sort the encoded elements according to their encoding.
     */
    qsort(encoded_els, eels_count, sizeof(encoded_els[0]), _el_buf_cmp);

    /*
     * Report encoded elements to the application.
     * Dispose of temporary sorted members table.
     */
    ret = 0;
    for(edx = 0; edx < eels_count; edx++) {
        struct _el_buffer *encoded_el = &encoded_els[edx];
        /* Report encoded chunks to the application */
        if(ret == 0
        && cb(encoded_el->buf, encoded_el->length, app_key) < 0)
            ret = -1;
        FREEMEM(encoded_el->buf);
    }
    FREEMEM(encoded_els);

    if(ret || computed_size != (size_t)encoding_size) {
        /*
         * Standard callback failed, or
         * encoded size is not equal to the computed size.
         */
        erval.encoded = -1;
        erval.failed_type = td;
        erval.structure_ptr = ptr;
    } else {
        erval.encoded = computed_size;
    }

    _ASN_ENCODED_OK(erval);
}

#undef  XER_ADVANCE
#define XER_ADVANCE(num_bytes)  do {            \
        size_t num = num_bytes;         \
        buf_ptr = ((const char *)buf_ptr) + num;\
        size -= num;                \
        consumed_myself += num;         \
    } while(0)

/*
 * Decode the XER (XML) data.
 */
asn_dec_rval_t
SET_OF_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
    void **struct_ptr, const char *opt_mname,
        const void *buf_ptr, size_t size) {
    /*
     * Bring closer parts of structure description.
     */
    asn_SET_OF_specifics_t *specs = (asn_SET_OF_specifics_t *)td->specifics;
    asn_TYPE_member_t *element = td->elements;
    const char *elm_tag;
    const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;

    /*
     * ... and parts of the structure being constructed.
     */
    void *st = *struct_ptr; /* Target structure. */
    asn_struct_ctx_t *ctx;  /* Decoder context */

    asn_dec_rval_t rval;        /* Return value from a decoder */
    ssize_t consumed_myself = 0;    /* Consumed bytes from ptr */

    /*
     * Create the target structure if it is not present already.
     */
    if(st == 0) {
        st = *struct_ptr = CALLOC(1, specs->struct_size);
        if(st == 0) RETURN(RC_FAIL);
    }

    /* Which tag is expected for the downstream */
    if(specs->as_XMLValueList) {
        elm_tag = (specs->as_XMLValueList == 1) ? 0 : "";
    } else {
        elm_tag = (*element->name)
                ? element->name : element->type->xml_tag;
    }

    /*
     * Restore parsing context.
     */
    ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);

    /*
     * Phases of XER/XML processing:
     * Phase 0: Check that the opening tag matches our expectations.
     * Phase 1: Processing body and reacting on closing tag.
     * Phase 2: Processing inner type.
     */
    for(; ctx->phase <= 2;) {
        pxer_chunk_type_e ch_type;  /* XER chunk type */
        ssize_t ch_size;        /* Chunk size */
        xer_check_tag_e tcv;        /* Tag check value */

        /*
         * Go inside the inner member of a set.
         */
        if(ctx->phase == 2) {
            asn_dec_rval_t tmprval;

            /* Invoke the inner type decoder, m.b. multiple times */
            ASN_DEBUG("XER/SET OF element [%s]", elm_tag);
            tmprval = element->type->xer_decoder(opt_codec_ctx,
                    element->type, &ctx->ptr, elm_tag,
                    buf_ptr, size);
            if(tmprval.code == RC_OK) {
                asn_anonymous_set_ *list = _A_SET_FROM_VOID(st);
                if(ASN_SET_ADD(list, ctx->ptr) != 0)
                    RETURN(RC_FAIL);
                ctx->ptr = 0;
                XER_ADVANCE(tmprval.consumed);
            } else {
                XER_ADVANCE(tmprval.consumed);
                RETURN(tmprval.code);
            }
            ctx->phase = 1; /* Back to body processing */
            ASN_DEBUG("XER/SET OF phase => %d", ctx->phase);
            /* Fall through */
        }

        /*
         * Get the next part of the XML stream.
         */
        ch_size = xer_next_token(&ctx->context,
            buf_ptr, size, &ch_type);
        switch(ch_size) {
        case -1: RETURN(RC_FAIL);
        case 0:  RETURN(RC_WMORE);
        default:
            switch(ch_type) {
            case PXER_COMMENT:  /* Got XML comment */
            case PXER_TEXT:     /* Ignore free-standing text */
                XER_ADVANCE(ch_size);   /* Skip silently */
                continue;
            case PXER_TAG:
                break;  /* Check the rest down there */
            }
        }

        tcv = xer_check_tag(buf_ptr, ch_size, xml_tag);
        ASN_DEBUG("XER/SET OF: tcv = %d, ph=%d t=%s",
            tcv, ctx->phase, xml_tag);
        switch(tcv) {
        case XCT_CLOSING:
            if(ctx->phase == 0) break;
            ctx->phase = 0;
            /* Fall through */
        case XCT_BOTH:
            if(ctx->phase == 0) {
                /* No more things to decode */
                XER_ADVANCE(ch_size);
                ctx->phase = 3; /* Phase out */
                RETURN(RC_OK);
            }
            /* Fall through */
        case XCT_OPENING:
            if(ctx->phase == 0) {
                XER_ADVANCE(ch_size);
                ctx->phase = 1; /* Processing body phase */
                continue;
            }
            /* Fall through */
        case XCT_UNKNOWN_OP:
        case XCT_UNKNOWN_BO:

            ASN_DEBUG("XER/SET OF: tcv=%d, ph=%d", tcv, ctx->phase);
            if(ctx->phase == 1) {
                /*
                 * Process a single possible member.
                 */
                ctx->phase = 2;
                continue;
            }
            /* Fall through */
        default:
            break;
        }

        ASN_DEBUG("Unexpected XML tag in SET OF");
        break;
    }

    ctx->phase = 3; /* "Phase out" on hard failure */
    RETURN(RC_FAIL);
}



typedef struct xer_tmp_enc_s {
    void *buffer;
    size_t offset;
    size_t size;
} xer_tmp_enc_t;
static int
SET_OF_encode_xer_callback(const void *buffer, size_t size, void *key) {
    xer_tmp_enc_t *t = (xer_tmp_enc_t *)key;
    if(t->offset + size >= t->size) {
        size_t newsize = (t->size << 2) + size;
        void *p = REALLOC(t->buffer, newsize);
        if(!p) return -1;
        t->buffer = p;
        t->size = newsize;
    }
    memcpy((char *)t->buffer + t->offset, buffer, size);
    t->offset += size;
    return 0;
}
static int
SET_OF_xer_order(const void *aptr, const void *bptr) {
    const xer_tmp_enc_t *a = (const xer_tmp_enc_t *)aptr;
    const xer_tmp_enc_t *b = (const xer_tmp_enc_t *)bptr;
    size_t minlen = a->offset;
    int ret;
    if(b->offset < minlen) minlen = b->offset;
    /* Well-formed UTF-8 has this nice lexicographical property... */
    ret = memcmp(a->buffer, b->buffer, minlen);
    if(ret != 0) return ret;
    if(a->offset == b->offset)
        return 0;
    if(a->offset == minlen)
        return -1;
    return 1;
}


asn_enc_rval_t
SET_OF_encode_xer(asn_TYPE_descriptor_t *td, void *sptr,
    int ilevel, enum xer_encoder_flags_e flags,
        asn_app_consume_bytes_f *cb, void *app_key) {
    asn_enc_rval_t er;
    asn_SET_OF_specifics_t *specs = (asn_SET_OF_specifics_t *)td->specifics;
    asn_TYPE_member_t *elm = td->elements;
    asn_anonymous_set_ *list = _A_SET_FROM_VOID(sptr);
    const char *mname = specs->as_XMLValueList
        ? 0 : ((*elm->name) ? elm->name : elm->type->xml_tag);
    size_t mlen = mname ? strlen(mname) : 0;
    int xcan = (flags & XER_F_CANONICAL);
    xer_tmp_enc_t *encs = 0;
    size_t encs_count = 0;
    void *original_app_key = app_key;
    asn_app_consume_bytes_f *original_cb = cb;
    int i;

    if(!sptr) _ASN_ENCODE_FAILED;

    if(xcan) {
        encs = (xer_tmp_enc_t *)MALLOC(list->count * sizeof(encs[0]));
        if(!encs) _ASN_ENCODE_FAILED;
        cb = SET_OF_encode_xer_callback;
    }

    er.encoded = 0;

    for(i = 0; i < list->count; i++) {
        asn_enc_rval_t tmper;

        void *memb_ptr = list->array[i];
        if(!memb_ptr) continue;

        if(encs) {
            memset(&encs[encs_count], 0, sizeof(encs[0]));
            app_key = &encs[encs_count];
            encs_count++;
        }

        if(mname) {
            if(!xcan) _i_ASN_TEXT_INDENT(1, ilevel);
            _ASN_CALLBACK3("<", 1, mname, mlen, ">", 1);
        }

        if(!xcan && specs->as_XMLValueList == 1)
            _i_ASN_TEXT_INDENT(1, ilevel + 1);
        tmper = elm->type->xer_encoder(elm->type, memb_ptr,
                ilevel + (specs->as_XMLValueList != 2),
                flags, cb, app_key);
        if(tmper.encoded == -1) {
            td = tmper.failed_type;
            sptr = tmper.structure_ptr;
            goto cb_failed;
        }
        if(tmper.encoded == 0 && specs->as_XMLValueList) {
            const char *name = elm->type->xml_tag;
            size_t len = strlen(name);
            _ASN_CALLBACK3("<", 1, name, len, "/>", 2);
        }

        if(mname) {
            _ASN_CALLBACK3("</", 2, mname, mlen, ">", 1);
            er.encoded += 5;
        }

        er.encoded += (2 * mlen) + tmper.encoded;
    }

    if(!xcan) _i_ASN_TEXT_INDENT(1, ilevel - 1);

    if(encs) {
        xer_tmp_enc_t *enc = encs;
        xer_tmp_enc_t *end = encs + encs_count;
        ssize_t control_size = 0;

        cb = original_cb;
        app_key = original_app_key;
        qsort(encs, encs_count, sizeof(encs[0]), SET_OF_xer_order);

        for(; enc < end; enc++) {
            _ASN_CALLBACK(enc->buffer, enc->offset);
            FREEMEM(enc->buffer);
            enc->buffer = 0;
            control_size += enc->offset;
        }
        assert(control_size == er.encoded);
    }

    goto cleanup;
cb_failed:
    er.encoded = -1;
    er.failed_type = td;
    er.structure_ptr = sptr;
cleanup:
    if(encs) {
        while(encs_count-- > 0) {
            if(encs[encs_count].buffer)
                FREEMEM(encs[encs_count].buffer);
        }
        FREEMEM(encs);
    }
    _ASN_ENCODED_OK(er);
}

int
SET_OF_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
        asn_app_consume_bytes_f *cb, void *app_key) {
    asn_TYPE_member_t *elm = td->elements;
    const asn_anonymous_set_ *list = _A_CSET_FROM_VOID(sptr);
    int ret;
    int i;

    if(!sptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;

    /* Dump preamble */
    if(cb(td->name, strlen(td->name), app_key) < 0
    || cb(" ::= {", 6, app_key) < 0)
        return -1;

    for(i = 0; i < list->count; i++) {
        const void *memb_ptr = list->array[i];
        if(!memb_ptr) continue;

        _i_INDENT(1);

        ret = elm->type->print_struct(elm->type, memb_ptr,
            ilevel + 1, cb, app_key);
        if(ret) return ret;
    }

    ilevel--;
    _i_INDENT(1);

    return (cb("}", 1, app_key) < 0) ? -1 : 0;
}

void
SET_OF_free(asn_TYPE_descriptor_t *td, void *ptr, int contents_only) {
    if(td && ptr) {
        asn_SET_OF_specifics_t *specs;
        asn_TYPE_member_t *elm = td->elements;
        asn_anonymous_set_ *list = _A_SET_FROM_VOID(ptr);
        asn_struct_ctx_t *ctx;  /* Decoder context */
        int i;

        /*
         * Could not use set_of_empty() because of (*free)
         * incompatibility.
         */
        for(i = 0; i < list->count; i++) {
            void *memb_ptr = list->array[i];
            if(memb_ptr)
            ASN_STRUCT_FREE(*elm->type, memb_ptr);
        }
        list->count = 0;    /* No meaningful elements left */

        asn_set_empty(list);    /* Remove (list->array) */

        specs = (asn_SET_OF_specifics_t *)td->specifics;
        ctx = (asn_struct_ctx_t *)((char *)ptr + specs->ctx_offset);
        if(ctx->ptr) {
            ASN_STRUCT_FREE(*elm->type, ctx->ptr);
            ctx->ptr = 0;
        }

        if(!contents_only) {
            FREEMEM(ptr);
        }
    }
}

int
SET_OF_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
        asn_app_constraint_failed_f *ctfailcb, void *app_key) {
    asn_TYPE_member_t *elm = td->elements;
    asn_constr_check_f *constr;
    const asn_anonymous_set_ *list = _A_CSET_FROM_VOID(sptr);
    int i;

    if(!sptr) {
        _ASN_CTFAIL(app_key, td, sptr,
            "%s: value not given (%s:%d)",
            td->name, __FILE__, __LINE__);
        return -1;
    }

    constr = elm->memb_constraints;
    if(!constr) constr = elm->type->check_constraints;

    /*
     * Iterate over the members of an array.
     * Validate each in turn, until one fails.
     */
    for(i = 0; i < list->count; i++) {
        const void *memb_ptr = list->array[i];
        int ret;

        if(!memb_ptr) continue;

        ret = constr(elm->type, memb_ptr, ctfailcb, app_key);
        if(ret) return ret;
    }

    /*
     * Cannot inherit it eralier:
     * need to make sure we get the updated version.
     */
    if(!elm->memb_constraints)
        elm->memb_constraints = elm->type->check_constraints;

    return 0;
}

asn_dec_rval_t
SET_OF_decode_uper(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
        asn_per_constraints_t *constraints, void **sptr, asn_per_data_t *pd) {
    asn_dec_rval_t rv;
        asn_SET_OF_specifics_t *specs = (asn_SET_OF_specifics_t *)td->specifics;
    asn_TYPE_member_t *elm = td->elements;  /* Single one */
    void *st = *sptr;
    asn_anonymous_set_ *list;
    asn_per_constraint_t *ct;
    int repeat = 0;
    ssize_t nelems;

    if(_ASN_STACK_OVERFLOW_CHECK(opt_codec_ctx))
        _ASN_DECODE_FAILED;

    /*
     * Create the target structure if it is not present already.
     */
    if(!st) {
        st = *sptr = CALLOC(1, specs->struct_size);
        if(!st) _ASN_DECODE_FAILED;
    }                                                                       
    list = _A_SET_FROM_VOID(st);

    /* Figure out which constraints to use */
    if(constraints) ct = &constraints->size;
    else if(td->per_constraints) ct = &td->per_constraints->size;
    else ct = 0;

    if(ct && ct->flags & APC_EXTENSIBLE) {
        int value = per_get_few_bits(pd, 1);
        if(value < 0) _ASN_DECODE_STARVED;
        if(value) ct = 0;   /* Not restricted! */
    }

    if(ct && ct->effective_bits >= 0) {
        /* X.691, #19.5: No length determinant */
        nelems = per_get_few_bits(pd, ct->effective_bits);
        ASN_DEBUG("Preparing to fetch %ld+%ld elements from %s",
            (long)nelems, ct->lower_bound, td->name);
        if(nelems < 0)  _ASN_DECODE_STARVED;
        nelems += ct->lower_bound;
    } else {
        nelems = -1;
    }

    do {
        int i;
        if(nelems < 0) {
            nelems = uper_get_length(pd,
                ct ? ct->effective_bits : -1, &repeat);
            ASN_DEBUG("Got to decode %d elements (eff %d)",
                (int)nelems, (int)(ct ? ct->effective_bits : -1));
            if(nelems < 0) _ASN_DECODE_STARVED;
        }

        for(i = 0; i < nelems; i++) {
            void *ptr = 0;
            ASN_DEBUG("SET OF %s decoding", elm->type->name);
            rv = elm->type->uper_decoder(opt_codec_ctx, elm->type,
                elm->per_constraints, &ptr, pd);
            ASN_DEBUG("%s SET OF %s decoded %d, %p",
                td->name, elm->type->name, rv.code, ptr);
            if(rv.code == RC_OK) {
                if(ASN_SET_ADD(list, ptr) == 0)
                    continue;
                ASN_DEBUG("Failed to add element into %s",
                    td->name);
                /* Fall through */
                rv.code = RC_FAIL;
            } else {
                ASN_DEBUG("Failed decoding %s of %s (SET OF)",
                    elm->type->name, td->name);
            }
            if(ptr) ASN_STRUCT_FREE(*elm->type, ptr);
            return rv;
        }

        nelems = -1;    /* Allow uper_get_length() */
    } while(repeat);

    ASN_DEBUG("Decoded %s as SET OF", td->name);

    rv.code = RC_OK;
    rv.consumed = 0;
    return rv;
}