]> git.stg.codes - stg.git/blobdiff - libs/smux/constr_CHOICE.c
Update README.
[stg.git] / libs / smux / constr_CHOICE.c
index 6116e6a6b0b47d989300d409c63a4241c0d10ff4..628979ec22b417f9c5570b4afc720eae944ac076 100644 (file)
@@ -1,6 +1,5 @@
 /*
- * Copyright (c) 2003, 2004, 2005, 2006, 2007 Lev Walkin <vlm@lionet.info>.
- * All rights reserved.
+ * Copyright (c) 2003-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
  * Redistribution and modifications are permitted subject to BSD license.
  */
 #include <asn_internal.h>
 /*
  * See the definitions.
  */
-static int _fetch_present_idx(const void *struct_ptr, int off, int size);
-static void _set_present_idx(void *sptr, int offset, int size, int pres);
+static unsigned _fetch_present_idx(const void *struct_ptr, unsigned off,
+                                   unsigned size);
+static void _set_present_idx(void *sptr, unsigned offset, unsigned size,
+                             unsigned pres);
+static const void *_get_member_ptr(const asn_TYPE_descriptor_t *,
+                                   const void *sptr, asn_TYPE_member_t **elm,
+                                   unsigned *present);
 
 /*
  * Tags are canonically sorted in the tag to member table.
@@ -98,12 +102,14 @@ _search4tag(const void *ap, const void *bp) {
  * The decoder of the CHOICE type.
  */
 asn_dec_rval_t
-CHOICE_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) {
-       /*
+CHOICE_decode_ber(const asn_codec_ctx_t *opt_codec_ctx,
+                  const asn_TYPE_descriptor_t *td, void **struct_ptr,
+                  const void *ptr, size_t size, int tag_mode) {
+    /*
         * Bring closer parts of structure description.
         */
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
+       const asn_CHOICE_specifics_t *specs =
+               (const asn_CHOICE_specifics_t *)td->specifics;
        asn_TYPE_member_t *elements = td->elements;
 
        /*
@@ -259,7 +265,7 @@ CHOICE_decode_ber(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                /*
                 * Invoke the member fetch routine according to member's type
                 */
-               rval = elm->type->ber_decoder(opt_codec_ctx, elm->type,
+               rval = elm->type->op->ber_decoder(opt_codec_ctx, elm->type,
                                memb_ptr2, ptr, LEFT, elm->tag_mode);
                switch(rval.code) {
                case RC_OK:
@@ -354,15 +360,15 @@ CHOICE_decode_ber(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
 }
 
 asn_enc_rval_t
-CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
-               int tag_mode, ber_tlv_tag_t tag,
-               asn_app_consume_bytes_f *cb, void *app_key) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
+CHOICE_encode_der(const asn_TYPE_descriptor_t *td, const void *sptr,
+                  int tag_mode, ber_tlv_tag_t tag, asn_app_consume_bytes_f *cb,
+                  void *app_key) {
+    const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
        asn_TYPE_member_t *elm; /* CHOICE element */
        asn_enc_rval_t erval;
-       void *memb_ptr;
+       const void *memb_ptr;
        size_t computed_size = 0;
-       int present;
+       unsigned present;
 
        if(!sptr) ASN__ENCODE_FAILED;
 
@@ -376,7 +382,7 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
         * If the structure was not initialized, it cannot be encoded:
         * can't deduce what to encode in the choice type.
         */
-       if(present <= 0 || present > td->elements_count) {
+       if(present == 0 || present > td->elements_count) {
                if(present == 0 && td->elements_count == 0) {
                        /* The CHOICE is empty?! */
                        erval.encoded = 0;
@@ -390,8 +396,9 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
         */
        elm = &td->elements[present-1];
        if(elm->flags & ATF_POINTER) {
-               memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
-               if(memb_ptr == 0) {
+        memb_ptr =
+            *(const void *const *)((const char *)sptr + elm->memb_offset);
+        if(memb_ptr == 0) {
                        if(elm->optional) {
                                erval.encoded = 0;
                                ASN__ENCODED_OK(erval);
@@ -400,8 +407,8 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
                        ASN__ENCODE_FAILED;
                }
        } else {
-               memb_ptr = (void *)((char *)sptr + elm->memb_offset);
-       }
+        memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
+    }
 
        /*
         * If the CHOICE itself is tagged EXPLICIT:
@@ -415,7 +422,7 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
                ssize_t ret;
 
                /* Encode member with its tag */
-               erval = elm->type->der_encoder(elm->type, memb_ptr,
+               erval = elm->type->op->der_encoder(elm->type, memb_ptr,
                        elm->tag_mode, elm->tag, 0, 0);
                if(erval.encoded == -1)
                        return erval;
@@ -431,7 +438,7 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
        /*
         * Encode the single underlying member.
         */
-       erval = elm->type->der_encoder(elm->type, memb_ptr,
+       erval = elm->type->op->der_encoder(elm->type, memb_ptr,
                elm->tag_mode, elm->tag, cb, app_key);
        if(erval.encoded == -1)
                return erval;
@@ -446,8 +453,8 @@ CHOICE_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
 
 ber_tlv_tag_t
 CHOICE_outmost_tag(const asn_TYPE_descriptor_t *td, const void *ptr, int tag_mode, ber_tlv_tag_t tag) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
-       int present;
+       const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
+       unsigned present;
 
        assert(tag_mode == 0); (void)tag_mode;
        assert(tag == 0); (void)tag;
@@ -457,7 +464,7 @@ CHOICE_outmost_tag(const asn_TYPE_descriptor_t *td, const void *ptr, int tag_mod
         */
        present = _fetch_present_idx(ptr, specs->pres_offset, specs->pres_size);
 
-       if(present > 0 || present <= td->elements_count) {
+       if(present > 0 && present <= td->elements_count) {
                const asn_TYPE_member_t *elm = &td->elements[present-1];
                const void *memb_ptr;
 
@@ -477,10 +484,11 @@ CHOICE_outmost_tag(const asn_TYPE_descriptor_t *td, const void *ptr, int tag_mod
 }
 
 int
-CHOICE_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
-               asn_app_constraint_failed_f *ctfailcb, void *app_key) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
-       int present;
+CHOICE_constraint(const asn_TYPE_descriptor_t *td, const void *sptr,
+                  asn_app_constraint_failed_f *ctfailcb, void *app_key) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    unsigned present;
 
        if(!sptr) {
                ASN__CTFAIL(app_key, td, sptr,
@@ -511,18 +519,12 @@ CHOICE_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
                        memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
                }
 
-               if(elm->memb_constraints) {
-                       return elm->memb_constraints(elm->type, memb_ptr,
+               if(elm->encoding_constraints.general_constraints) {
+                       return elm->encoding_constraints.general_constraints(elm->type, memb_ptr,
                                ctfailcb, app_key);
                } else {
-                       int ret = elm->type->check_constraints(elm->type,
+                       return elm->type->encoding_constraints.general_constraints(elm->type,
                                        memb_ptr, ctfailcb, app_key);
-                       /*
-                        * Cannot inherit it eralier:
-                        * need to make sure we get the updated version.
-                        */
-                       elm->memb_constraints = elm->type->check_constraints;
-                       return ret;
                }
        } else {
                ASN__CTFAIL(app_key, td, sptr,
@@ -544,13 +546,13 @@ CHOICE_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
  * Decode the XER (XML) data.
  */
 asn_dec_rval_t
-CHOICE_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) {
-       /*
+CHOICE_decode_xer(const asn_codec_ctx_t *opt_codec_ctx,
+                  const 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_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
+       const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
        const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;
 
        /*
@@ -561,7 +563,7 @@ CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
 
        asn_dec_rval_t rval;            /* Return value of a decoder */
        ssize_t consumed_myself = 0;    /* Consumed bytes from ptr */
-       int edx;                        /* Element index */
+       size_t edx;                     /* Element index */
 
        /*
         * Create the target structure if it is not present already.
@@ -600,6 +602,7 @@ CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                        asn_dec_rval_t tmprval;
                        void *memb_ptr;         /* Pointer to the member */
                        void **memb_ptr2;       /* Pointer to that pointer */
+                       unsigned old_present;
 
                        elm = &td->elements[edx];
 
@@ -613,19 +616,20 @@ CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                        }
 
                        /* Start/Continue decoding the inner member */
-                       tmprval = elm->type->xer_decoder(opt_codec_ctx,
+                       tmprval = elm->type->op->xer_decoder(opt_codec_ctx,
                                        elm->type, memb_ptr2, elm->name,
                                        buf_ptr, size);
                        XER_ADVANCE(tmprval.consumed);
                        ASN_DEBUG("XER/CHOICE: itdf: [%s] code=%d",
                                elm->type->name, tmprval.code);
-                       if(tmprval.code != RC_OK)
-                               RETURN(tmprval.code);
-                       assert(_fetch_present_idx(st,
-                               specs->pres_offset, specs->pres_size) == 0);
+                       old_present = _fetch_present_idx(st,
+                               specs->pres_offset, specs->pres_size);
+                       assert(old_present == 0 || old_present == edx + 1);
                        /* Record what we've got */
                        _set_present_idx(st,
                                specs->pres_offset, specs->pres_size, edx + 1);
+                       if(tmprval.code != RC_OK)
+                               RETURN(tmprval.code);
                        ctx->phase = 3;
                        /* Fall through */
                }
@@ -671,7 +675,6 @@ CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                        case -1:
                                ctx->phase = 5;
                                RETURN(RC_FAIL);
-                               continue;
                        case 1:
                                ctx->phase = 3;
                                /* Fall through */
@@ -773,12 +776,13 @@ CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
 
 
 asn_enc_rval_t
-CHOICE_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_CHOICE_specifics_t *specs=(asn_CHOICE_specifics_t *)td->specifics;
-       asn_enc_rval_t er;
-       int present;
+CHOICE_encode_xer(const asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
+                  enum xer_encoder_flags_e flags, asn_app_consume_bytes_f *cb,
+                  void *app_key) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    asn_enc_rval_t er;
+       unsigned present;
 
        if(!sptr)
                ASN__ENCODE_FAILED;
@@ -788,34 +792,34 @@ CHOICE_encode_xer(asn_TYPE_descriptor_t *td, void *sptr,
         */
        present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);
 
-       if(present <= 0 || present > td->elements_count) {
+       if(present == 0 || present > td->elements_count) {
                ASN__ENCODE_FAILED;
        }  else {
                asn_enc_rval_t tmper;
                asn_TYPE_member_t *elm = &td->elements[present-1];
-               void *memb_ptr;
+               const void *memb_ptr;
                const char *mname = elm->name;
                unsigned int mlen = strlen(mname);
 
                if(elm->flags & ATF_POINTER) {
-                       memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
-                       if(!memb_ptr) ASN__ENCODE_FAILED;
+            memb_ptr =
+                *(const void *const *)((const char *)sptr + elm->memb_offset);
+            if(!memb_ptr) ASN__ENCODE_FAILED;
                } else {
-                       memb_ptr = (void *)((char *)sptr + elm->memb_offset);
-               }
+            memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
+        }
 
-               er.encoded = 0;
+        er.encoded = 0;
 
-                if(!(flags & XER_F_CANONICAL)) ASN__TEXT_INDENT(1, ilevel);
+               if(!(flags & XER_F_CANONICAL)) ASN__TEXT_INDENT(1, ilevel);
                ASN__CALLBACK3("<", 1, mname, mlen, ">", 1);
 
-               tmper = elm->type->xer_encoder(elm->type, memb_ptr,
+               tmper = elm->type->op->xer_encoder(elm->type, memb_ptr,
                                ilevel + 1, flags, cb, app_key);
                if(tmper.encoded == -1) return tmper;
+               er.encoded += tmper.encoded;
 
                ASN__CALLBACK3("</", 2, mname, mlen, ">", 1);
-
-               er.encoded += 5 + (2 * mlen) + tmper.encoded;
        }
 
        if(!(flags & XER_F_CANONICAL)) ASN__TEXT_INDENT(1, ilevel - 1);
@@ -826,11 +830,14 @@ cb_failed:
 }
 
 asn_dec_rval_t
-CHOICE_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_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
-       asn_dec_rval_t rv;
-       asn_per_constraint_t *ct;
+CHOICE_decode_uper(const asn_codec_ctx_t *opt_codec_ctx,
+                   const asn_TYPE_descriptor_t *td,
+                   const asn_per_constraints_t *constraints, void **sptr,
+                   asn_per_data_t *pd) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    asn_dec_rval_t rv;
+       const asn_per_constraint_t *ct;
        asn_TYPE_member_t *elm; /* CHOICE's element */
        void *memb_ptr;
        void **memb_ptr2;
@@ -849,7 +856,7 @@ CHOICE_decode_uper(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
        }
 
        if(constraints) ct = &constraints->value;
-       else if(td->per_constraints) ct = &td->per_constraints->value;
+       else if(td->encoding_constraints.per_constraints) ct = &td->encoding_constraints.per_constraints->value;
        else ct = 0;
 
        if(ct && ct->flags & APC_EXTENSIBLE) {
@@ -871,13 +878,16 @@ CHOICE_decode_uper(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                value = uper_get_nsnnwn(pd);
                if(value < 0) ASN__DECODE_STARVED;
                value += specs->ext_start;
-               if(value >= td->elements_count)
+               if((unsigned)value >= td->elements_count)
                        ASN__DECODE_FAILED;
        }
 
        /* Adjust if canonical order is different from natural order */
-       if(specs->canonical_order)
-               value = specs->canonical_order[value];
+       if(specs->from_canonical_order) {
+        ASN_DEBUG("CHOICE presence from wire %d", value);
+               value = specs->from_canonical_order[value];
+        ASN_DEBUG("CHOICE presence index effective %d", value);
+    }
 
        /* Set presence to be able to free it later */
        _set_present_idx(st, specs->pres_offset, specs->pres_size, value + 1);
@@ -893,11 +903,11 @@ CHOICE_decode_uper(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
        ASN_DEBUG("Discovered CHOICE %s encodes %s", td->name, elm->name);
 
        if(ct && ct->range_bits >= 0) {
-               rv = elm->type->uper_decoder(opt_codec_ctx, elm->type,
-                       elm->per_constraints, memb_ptr2, pd);
+               rv = elm->type->op->uper_decoder(opt_codec_ctx, elm->type,
+                       elm->encoding_constraints.per_constraints, memb_ptr2, pd);
        } else {
                rv = uper_open_type_get(opt_codec_ctx, elm->type,
-                       elm->per_constraints, memb_ptr2, pd);
+                       elm->encoding_constraints.per_constraints, memb_ptr2, pd);
        }
 
        if(rv.code != RC_OK)
@@ -905,15 +915,16 @@ CHOICE_decode_uper(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
                        elm->name, td->name, rv.code);
        return rv;
 }
-   
+
 asn_enc_rval_t
-CHOICE_encode_uper(asn_TYPE_descriptor_t *td,
-       asn_per_constraints_t *constraints, void *sptr, asn_per_outp_t *po) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
+CHOICE_encode_uper(const asn_TYPE_descriptor_t *td,
+                   const asn_per_constraints_t *constraints, const void *sptr,
+                   asn_per_outp_t *po) {
+    const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
        asn_TYPE_member_t *elm; /* CHOICE's element */
-       asn_per_constraint_t *ct;
-       void *memb_ptr;
-       int present;
+       const asn_per_constraint_t *ct;
+       const void *memb_ptr;
+       unsigned present;
        int present_enc;
 
        if(!sptr) ASN__ENCODE_FAILED;
@@ -921,34 +932,37 @@ CHOICE_encode_uper(asn_TYPE_descriptor_t *td,
        ASN_DEBUG("Encoding %s as CHOICE", td->name);
 
        if(constraints) ct = &constraints->value;
-       else if(td->per_constraints) ct = &td->per_constraints->value;
+       else if(td->encoding_constraints.per_constraints)
+               ct = &td->encoding_constraints.per_constraints->value;
        else ct = 0;
 
-       present = _fetch_present_idx(sptr,
-               specs->pres_offset, specs->pres_size);
+       present = _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
 
        /*
         * If the structure was not initialized properly, it cannot be encoded:
         * can't deduce what to encode in the choice type.
         */
-       if(present <= 0 || present > td->elements_count)
+       if(present == 0 || present > td->elements_count)
                ASN__ENCODE_FAILED;
        else
                present--;
 
        ASN_DEBUG("Encoding %s CHOICE element %d", td->name, present);
 
-       /* Adjust if canonical order is different from natural order */
-       if(specs->canonical_order)
-               present_enc = specs->canonical_order[present];
-       else
-               present_enc = present;
+    /* Adjust if canonical order is different from natural order */
+    if(specs->to_canonical_order)
+        present_enc = specs->to_canonical_order[present];
+    else
+        present_enc = present;
 
-       if(ct && ct->range_bits >= 0) {
+    if(ct && ct->range_bits >= 0) {
                if(present_enc < ct->lower_bound
                || present_enc > ct->upper_bound) {
                        if(ct->flags & APC_EXTENSIBLE) {
-                               if(per_put_few_bits(po, 1, 1))
+                ASN_DEBUG(
+                    "CHOICE member %d (enc %d) is an extension (%ld..%ld)",
+                    present, present_enc, ct->lower_bound, ct->upper_bound);
+                if(per_put_few_bits(po, 1, 1))
                                        ASN__ENCODE_FAILED;
                        } else {
                                ASN__ENCODE_FAILED;
@@ -956,45 +970,52 @@ CHOICE_encode_uper(asn_TYPE_descriptor_t *td,
                        ct = 0;
                }
        }
-       if(ct && ct->flags & APC_EXTENSIBLE)
-               if(per_put_few_bits(po, 0, 1))
+       if(ct && ct->flags & APC_EXTENSIBLE) {
+        ASN_DEBUG("CHOICE member %d (enc %d) is not an extension (%ld..%ld)",
+                  present, present_enc, ct->lower_bound, ct->upper_bound);
+        if(per_put_few_bits(po, 0, 1))
                        ASN__ENCODE_FAILED;
+    }
+
 
        elm = &td->elements[present];
-       if(elm->flags & ATF_POINTER) {
+    ASN_DEBUG("CHOICE member \"%s\" %d (as %d)", elm->name, present,
+              present_enc);
+    if(elm->flags & ATF_POINTER) {
                /* Member is a pointer to another structure */
-               memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
-               if(!memb_ptr) ASN__ENCODE_FAILED;
-       } else {
-               memb_ptr = (char *)sptr + elm->memb_offset;
-       }
-
-       if(ct && ct->range_bits >= 0) {
-               if(per_put_few_bits(po, present_enc, ct->range_bits))
-                       ASN__ENCODE_FAILED;
-
-               return elm->type->uper_encoder(elm->type, elm->per_constraints,
-                       memb_ptr, po);
+        memb_ptr =
+            *(const void *const *)((const char *)sptr + elm->memb_offset);
+        if(!memb_ptr) ASN__ENCODE_FAILED;
        } else {
-               asn_enc_rval_t rval;
-               if(specs->ext_start == -1)
-                       ASN__ENCODE_FAILED;
-               if(uper_put_nsnnwn(po, present_enc - specs->ext_start))
-                       ASN__ENCODE_FAILED;
-               if(uper_open_type_put(elm->type, elm->per_constraints,
-                       memb_ptr, po))
-                       ASN__ENCODE_FAILED;
-               rval.encoded = 0;
-               ASN__ENCODED_OK(rval);
-       }
+        memb_ptr = (const char *)sptr + elm->memb_offset;
+    }
+
+    if(ct && ct->range_bits >= 0) {
+        if(per_put_few_bits(po, present_enc, ct->range_bits))
+            ASN__ENCODE_FAILED;
+
+        return elm->type->op->uper_encoder(
+            elm->type, elm->encoding_constraints.per_constraints, memb_ptr, po);
+    } else {
+        asn_enc_rval_t rval;
+        if(specs->ext_start == -1) ASN__ENCODE_FAILED;
+        if(uper_put_nsnnwn(po, present_enc - specs->ext_start))
+            ASN__ENCODE_FAILED;
+        if(uper_open_type_put(elm->type,
+                              elm->encoding_constraints.per_constraints,
+                              memb_ptr, po))
+            ASN__ENCODE_FAILED;
+        rval.encoded = 0;
+        ASN__ENCODED_OK(rval);
+    }
 }
-   
+
 
 int
-CHOICE_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
-               asn_app_consume_bytes_f *cb, void *app_key) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
-       int present;
+CHOICE_print(const asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
+             asn_app_consume_bytes_f *cb, void *app_key) {
+    const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
+       unsigned present;
 
        if(!sptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
 
@@ -1024,7 +1045,7 @@ CHOICE_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
                                return -1;
                }
 
-               return elm->type->print_struct(elm->type, memb_ptr, ilevel,
+               return elm->type->op->print_struct(elm->type, memb_ptr, ilevel,
                        cb, app_key);
        } else {
                return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
@@ -1032,9 +1053,11 @@ CHOICE_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
 }
 
 void
-CHOICE_free(asn_TYPE_descriptor_t *td, void *ptr, int contents_only) {
-       asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
-       int present;
+CHOICE_free(const asn_TYPE_descriptor_t *td, void *ptr,
+            enum asn_struct_free_method method) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    unsigned present;
 
        if(!td || !ptr)
                return;
@@ -1063,9 +1086,16 @@ CHOICE_free(asn_TYPE_descriptor_t *td, void *ptr, int contents_only) {
                }
        }
 
-       if(!contents_only) {
-               FREEMEM(ptr);
-       }
+    switch(method) {
+    case ASFM_FREE_EVERYTHING:
+        FREEMEM(ptr);
+        break;
+    case ASFM_FREE_UNDERLYING:
+        break;
+    case ASFM_FREE_UNDERLYING_AND_RESET:
+        memset(ptr, 0, specs->struct_size);
+        break;
+    }
 }
 
 
@@ -1078,17 +1108,18 @@ CHOICE_free(asn_TYPE_descriptor_t *td, void *ptr, int contents_only) {
  * is guaranteed to be aligned properly. ASN.1 compiler itself does not
  * produce packed code.
  */
-static int
-_fetch_present_idx(const void *struct_ptr, int pres_offset, int pres_size) {
-       const void *present_ptr;
-       int present;
+static unsigned
+_fetch_present_idx(const void *struct_ptr, unsigned pres_offset,
+                   unsigned pres_size) {
+    const void *present_ptr;
+       unsigned present;
 
        present_ptr = ((const char *)struct_ptr) + pres_offset;
 
        switch(pres_size) {
-       case sizeof(int):       present =   *(const int *)present_ptr; break;
-       case sizeof(short):     present = *(const short *)present_ptr; break;
-       case sizeof(char):      present =  *(const char *)present_ptr; break;
+       case sizeof(int):       present = *(const unsigned int *)present_ptr; break;
+       case sizeof(short):     present = *(const unsigned short *)present_ptr; break;
+       case sizeof(char):      present = *(const unsigned char *)present_ptr; break;
        default:
                /* ANSI C mandates enum to be equivalent to integer */
                assert(pres_size != sizeof(int));
@@ -1099,16 +1130,211 @@ _fetch_present_idx(const void *struct_ptr, int pres_offset, int pres_size) {
 }
 
 static void
-_set_present_idx(void *struct_ptr, int pres_offset, int pres_size, int present) {
-       void *present_ptr;
+_set_present_idx(void *struct_ptr, unsigned pres_offset, unsigned pres_size,
+                 unsigned present) {
+    void *present_ptr;
        present_ptr = ((char *)struct_ptr) + pres_offset;
 
        switch(pres_size) {
-       case sizeof(int):       *(int *)present_ptr   = present; break;
-       case sizeof(short):     *(short *)present_ptr = present; break;
-       case sizeof(char):      *(char *)present_ptr  = present; break;
+       case sizeof(int):       *(unsigned int *)present_ptr   = present; break;
+       case sizeof(short):     *(unsigned short *)present_ptr = present; break;
+       case sizeof(char):      *(unsigned char *)present_ptr  = present; break;
        default:
                /* ANSI C mandates enum to be equivalent to integer */
                assert(pres_size != sizeof(int));
        }
 }
+
+static const void *
+_get_member_ptr(const asn_TYPE_descriptor_t *td, const void *sptr,
+                asn_TYPE_member_t **elm_ptr, unsigned *present_out) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    unsigned present;
+
+    if(!sptr) {
+        *elm_ptr = NULL;
+        *present_out = 0;
+        return NULL;
+    }
+
+    /*
+        * Figure out which CHOICE element is encoded.
+        */
+       present = _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
+    *present_out = present;
+
+    /*
+     * The presence index is intentionally 1-based to avoid
+     * treating zeroed structure as a valid one.
+     */
+       if(present > 0 && present <= td->elements_count) {
+        asn_TYPE_member_t *const elm = &td->elements[present - 1];
+        const void *memb_ptr;
+
+               if(elm->flags & ATF_POINTER) {
+            memb_ptr =
+                *(const void *const *)((const char *)sptr + elm->memb_offset);
+        } else {
+            memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
+        }
+        *elm_ptr = elm;
+        return memb_ptr;
+    } else {
+        *elm_ptr = NULL;
+        return NULL;
+    }
+
+}
+
+int
+CHOICE_compare(const asn_TYPE_descriptor_t *td, const void *aptr, const void *bptr) {
+    asn_TYPE_member_t *aelm;
+    asn_TYPE_member_t *belm;
+    unsigned apresent = 0;
+    unsigned bpresent = 0;
+    const void *amember = _get_member_ptr(td, aptr, &aelm, &apresent);
+    const void *bmember = _get_member_ptr(td, bptr, &belm, &bpresent);
+
+    if(amember && bmember) {
+        if(apresent == bpresent) {
+            assert(aelm == belm);
+            return aelm->type->op->compare_struct(aelm->type, amember, bmember);
+        } else if(apresent < bpresent) {
+            return -1;
+        } else {
+            return 1;
+        }
+    } else if(!amember) {
+        return -1;
+    } else {
+        return 1;
+    }
+}
+
+/*
+ * Return the 1-based choice variant presence index.
+ * Returns 0 in case of error.
+ */
+unsigned
+CHOICE_variant_get_presence(const asn_TYPE_descriptor_t *td, const void *sptr) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    return _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
+}
+
+/*
+ * Sets or resets the 1-based choice variant presence index.
+ * In case a previous index is not zero, the currently selected structure
+ * member is freed and zeroed-out first.
+ * Returns 0 on success and -1 on error.
+ */
+int
+CHOICE_variant_set_presence(const asn_TYPE_descriptor_t *td, void *sptr,
+                            unsigned present) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    unsigned old_present;
+
+    if(!sptr) {
+        return -1;
+    }
+
+    if(present > td->elements_count)
+        return -1;
+
+    old_present =
+        _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
+    if(present == old_present)
+        return 0;
+
+    if(old_present != 0) {
+        assert(old_present <= td->elements_count);
+        ASN_STRUCT_RESET(*td, sptr);
+    }
+
+    _set_present_idx(sptr, specs->pres_offset, specs->pres_size, present);
+
+    return 0;
+}
+
+
+asn_random_fill_result_t
+CHOICE_random_fill(const asn_TYPE_descriptor_t *td, void **sptr,
+                   const asn_encoding_constraints_t *constr,
+                   size_t max_length) {
+    const asn_CHOICE_specifics_t *specs =
+        (const asn_CHOICE_specifics_t *)td->specifics;
+    asn_random_fill_result_t res;
+    asn_random_fill_result_t result_failed = {ARFILL_FAILED, 0};
+    asn_random_fill_result_t result_skipped = {ARFILL_SKIPPED, 0};
+    const asn_TYPE_member_t *elm;
+    unsigned present;
+    void *memb_ptr;   /* Pointer to the member */
+    void **memb_ptr2; /* Pointer to that pointer */
+    void *st = *sptr;
+
+    if(max_length == 0) return result_skipped;
+
+    (void)constr;
+
+    if(st == NULL) {
+        st = CALLOC(1, specs->struct_size);
+        if(st == NULL) {
+            return result_failed;
+        }
+    }
+
+    present = asn_random_between(1, td->elements_count);
+    elm = &td->elements[present - 1];
+
+       if(elm->flags & ATF_POINTER) {
+               /* Member is a pointer to another structure */
+               memb_ptr2 = (void **)((char *)st + elm->memb_offset);
+       } else {
+               memb_ptr = (char *)st + elm->memb_offset;
+               memb_ptr2 = &memb_ptr;
+       }
+
+    res = elm->type->op->random_fill(elm->type, memb_ptr2,
+                                    &elm->encoding_constraints, max_length);
+    _set_present_idx(st, specs->pres_offset, specs->pres_size, present);
+    if(res.code == ARFILL_OK) {
+        *sptr = st;
+    } else {
+        if(st == *sptr) {
+            ASN_STRUCT_RESET(*td, st);
+        } else {
+            ASN_STRUCT_FREE(*td, st);
+        }
+    }
+
+    return res;
+}
+
+
+asn_TYPE_operation_t asn_OP_CHOICE = {
+       CHOICE_free,
+       CHOICE_print,
+       CHOICE_compare,
+       CHOICE_decode_ber,
+       CHOICE_encode_der,
+       CHOICE_decode_xer,
+       CHOICE_encode_xer,
+#ifdef ASN_DISABLE_OER_SUPPORT
+       0,
+       0,
+#else
+       CHOICE_decode_oer,
+       CHOICE_encode_oer,
+#endif  /* ASN_DISABLE_OER_SUPPORT */
+#ifdef ASN_DISABLE_PER_SUPPORT
+       0,
+       0,
+#else
+       CHOICE_decode_uper,
+       CHOICE_encode_uper,
+#endif /* ASN_DISABLE_PER_SUPPORT */
+       CHOICE_random_fill,
+       CHOICE_outmost_tag
+};