Previous commit was wrong - va_end(args) is called once, and right where it belongs.

This is #401 from vlm/asn1c by @Inksz.

From his PR:
I do not know the project's code-style, in some C projects this kind of error-handling would incorporate a goto.
But because of the general avoidance of goto I added va_end before each return.

I suppose has more insight into what this function does, one could "dry" the error handling.

jer: Minified JSON option

jer: UTF-8 escape control chars and handle escaped unicodes

APER: fix non negative normally small whole numbers

jer: REAL special values fix

aper_put_nsnnwn() and aper_get_nsnnwn() were wrong. All the places
where they were used are modified, if needed.

The functions aper_get_constrained_whole_number() and
aper_put_constrained_whole_number() are introduced.
They don't cover all cases, very big numbers are not supported.

The sample ASN.1 file and C program at the end show some issues.

For sequence-of, APER decoding fails and the XER output after
APER encode/decode is:

-----------
xer after encode/decode:
<ListOfInt>
    <INTEGER>1</INTEGER>
    <INTEGER>259</INTEGER>
</ListOfInt>
-----------

instead of:

-----------
xer after encode/decode:
<ListOfInt>
    <INTEGER>1</INTEGER>
    <INTEGER>2</INTEGER>
    <INTEGER>3</INTEGER>
</ListOfInt>
-----------

For the enum test, we have:

-----------
aper ue lost[1]: d4
-----------

instead of:

-----------
aper ue lost[1]: 95
-----------

And APER decoding fails.

For the choice test, we see:

-----------
aper snssai[3]: 80 01 00
-----------

instead of:

-----------
aper snssai[3]: 84 01 00
-----------

And XER after encode/decode is wrong.

To generate C code from the ASN.1 file, asn1c is run as:
asn1c -pdu=all -fno-include-deps -fcompound-names -gen-UPER -no-gen-BER -no-gen-JER -no-gen-OER -gen-APER -no-gen-example

ASN.1 file:

-----------
Test DEFINITIONS AUTOMATIC TAGS ::=

BEGIN

TestCond-Type ::= CHOICE{
        gBR                                     ENUMERATED {true, ...},
        aMBR                            ENUMERATED {true, ...},
        isStat                          ENUMERATED {true, ...},
        isCatM                          ENUMERATED {true, ...},
        rSRP                            ENUMERATED {true, ...},
        rSRQ                            ENUMERATED {true, ...},
        ...,
        ul-rSRP                         ENUMERATED {true, ...},
        cQI                                     ENUMERATED {true, ...},
        fiveQI                          ENUMERATED {true, ...},
        qCI                                     ENUMERATED {true, ...},
        sNSSAI                          ENUMERATED {true, ...}
}

CauseRadioNetwork ::= ENUMERATED {
        handover-desirable-for-radio-reasons,
        time-critical-handover,
        resource-optimisation-handover,
        reduce-load-in-serving-cell,
        partial-handover,
        unknown-new-eNB-UE-X2AP-ID,
        unknown-old-eNB-UE-X2AP-ID,
        unknown-pair-of-UE-X2AP-ID,
        ho-target-not-allowed,
        tx2relocoverall-expiry,
        trelocprep-expiry,
        cell-not-available,
        no-radio-resources-available-in-target-cell,
        invalid-MME-GroupID,
        unknown-MME-Code,
        encryption-and-or-integrity-protection-algorithms-not-supported,
        reportCharacteristicsEmpty,
        noReportPeriodicity,
        existingMeasurementID,
        unknown-eNB-Measurement-ID,
        measurement-temporarily-not-available,
        unspecified,
        ...,
        load-balancing,
        handover-optimisation,
        value-out-of-allowed-range,
        multiple-E-RAB-ID-instances,
        switch-off-ongoing,
        not-supported-QCI-value,
        measurement-not-supported-for-the-object,
        tDCoverall-expiry,
        tDCprep-expiry,
        action-desirable-for-radio-reasons,
        reduce-load,
        resource-optimisation,
        time-critical-action,
        target-not-allowed,
        no-radio-resources-available,
        invalid-QoS-combination,
        encryption-algorithms-not-supported,
        procedure-cancelled,
        rRM-purpose,
        improve-user-bit-rate,
        user-inactivity,
        radio-connection-with-UE-lost,
        failure-in-the-radio-interface-procedure,
        bearer-option-not-supported,
        mCG-Mobility,
        sCG-Mobility,
        count-reaches-max-value,
        unknown-old-en-gNB-UE-X2AP-ID,
        pDCP-Overload
}

ListOfInt ::= SEQUENCE (SIZE (3)) OF INTEGER

END
-----------

C program:

-----------

void test(void *v, int is_aper, char *name, void *t)
{
  unsigned char b[128];
  asn_enc_rval_t r = asn_encode_to_buffer(NULL,
                       is_aper ? ATS_ALIGNED_BASIC_PER
                               : ATS_UNALIGNED_BASIC_PER,
                       t, v, b, sizeof(b));
  if (r.encoded <= 0) printf("error\n"); else printf("ok\n");
  printf("%s %s[%ld]:", is_aper ? "aper" : "uper", name, r.encoded);
  for (int i = 0; i < r.encoded; i++) printf(" %2.2x", b[i]);
  printf("\n");

  void *ret = NULL;
  asn_dec_rval_t d = asn_decode(NULL,
                       is_aper ? ATS_ALIGNED_BASIC_PER
                               : ATS_UNALIGNED_BASIC_PER,
                       t, &ret, b, r.encoded);
  if (d.consumed != r.encoded) printf("error\n"); else printf("ok\n");
  printf("xer of input:\n");
  xer_fprint(stdout, t, v);
  printf("xer after encode/decode:\n");
  xer_fprint(stdout, t, ret);
}

int main(void)
{
  /* test sequence of */
  ListOfInt_t l = { 0 };
  long val[3] = { 1, 2, 3 };
  asn_sequence_add(&l.list, &val[0]);
  asn_sequence_add(&l.list, &val[1]);
  asn_sequence_add(&l.list, &val[2]);
  test(&l, 1, "sequence-of (size 3)", &asn_DEF_ListOfInt);
  test(&l, 0, "sequence-of (size 3)", &asn_DEF_ListOfInt);

  /* test enum */
  CauseRadioNetwork_t v;
  v = CauseRadioNetwork_radio_connection_with_UE_lost;

  test(&v, 1, "ue lost", &asn_DEF_CauseRadioNetwork);
  test(&v, 0, "ue lost", &asn_DEF_CauseRadioNetwork);

  v = CauseRadioNetwork_cell_not_available;

  test(&v, 1, "no cell", &asn_DEF_CauseRadioNetwork);
  test(&v, 0, "no cell", &asn_DEF_CauseRadioNetwork);

  /* test choice */
  TestCond_Type_t w;
  w.present = TestCond_Type_PR_sNSSAI;
  w.choice.sNSSAI = TestCond_Type__sNSSAI_true;

  test(&w, 1, "snssai", &asn_DEF_TestCond_Type);
  test(&w, 0, "snssai", &asn_DEF_TestCond_Type);

  w.present = TestCond_Type_PR_gBR;
  w.choice.sNSSAI = TestCond_Type__gBR_true;

  test(&w, 1, "gbr", &asn_DEF_TestCond_Type);
  test(&w, 0, "gbr", &asn_DEF_TestCond_Type);

  return 0;
}
-----------

jer: SET fix

SEQUENCE_free, CHOICE_free null pointer check fix

PER: fix encoding and decoding of OPENTYPE with size constraints

Constraints have to be used. If not the encoding or decoding may be
wrong.

For example RRC-Version of 3GPP 38.473 contains an extension with a
fixed size constraint (so the size is not encoded).

Here is a small ASN.1 file extracted from 38.473 to illustrate the
problem.

----
F1AP-PDU-Descriptions  {
itu-t (0) identified-organization (4) etsi (0) mobileDomain (0)
ngran-access (22) modules (3) f1ap (3) version1 (1) f1ap-PDU-Descriptions (0)}

DEFINITIONS AUTOMATIC TAGS ::=

BEGIN

ProtocolExtensionID     ::= INTEGER (0..65535)
Criticality             ::= ENUMERATED { reject, ignore, notify }
Presence                ::= ENUMERATED { optional, conditional, mandatory }
maxProtocolExtensions                                   INTEGER ::= 65535
id-latest-RRC-Version-Enhanced                                          ProtocolIE-ID ::= 199

ProtocolIE-ID           ::= INTEGER (0..65535)

F1AP-PROTOCOL-EXTENSION ::= CLASS {
        &id                             ProtocolExtensionID                     UNIQUE,
        &criticality    Criticality,
        &Extension,
        &presence               Presence
}
WITH SYNTAX {
        ID                              &id
        CRITICALITY             &criticality
        EXTENSION               &Extension
        PRESENCE                &presence
}

ProtocolExtensionContainer {F1AP-PROTOCOL-EXTENSION : ExtensionSetParam} ::=
        SEQUENCE (SIZE (1..maxProtocolExtensions)) OF
        ProtocolExtensionField {{ExtensionSetParam}}

ProtocolExtensionField {F1AP-PROTOCOL-EXTENSION : ExtensionSetParam} ::= SEQUENCE {
        id                                      F1AP-PROTOCOL-EXTENSION.&id                             ({ExtensionSetParam}),
        criticality                     F1AP-PROTOCOL-EXTENSION.&criticality    ({ExtensionSetParam}{@id}),
        extensionValue          F1AP-PROTOCOL-EXTENSION.&Extension              ({ExtensionSetParam}{@id})
}

RRC-Version ::= SEQUENCE        {
        latest-RRC-Version                      BIT STRING (SIZE(3)),
        iE-Extensions                           ProtocolExtensionContainer { { RRC-Version-ExtIEs } }   OPTIONAL}

RRC-Version-ExtIEs      F1AP-PROTOCOL-EXTENSION ::= {
        {ID id-latest-RRC-Version-Enhanced              CRITICALITY ignore EXTENSION OCTET STRING (SIZE(3))             PRESENCE optional },
        ...
}

END
----

And a small program to test:

----

int main(void)
{
  RRC_Version_t version;
  unsigned char x;
  char out[1024];

  unsigned char ver3[3] = { 0x11, 0x05, 0x01 };

  version.latest_RRC_Version.buf = &x;
  version.latest_RRC_Version.buf[0] = 0xe0;
  version.latest_RRC_Version.size = 1;
  version.latest_RRC_Version.bits_unused = 5;

  ProtocolExtensionContainer_32P0_t ext = { 0 };

  RRC_Version_ExtIEs_t ie;
  ie.id = ProtocolIE_ID_id_latest_RRC_Version_Enhanced;
  ie.criticality = Criticality_ignore;
  ie.extensionValue.present = RRC_Version_ExtIEs__extensionValue_PR_OCTET_STRING_SIZE_3_;
  ie.extensionValue.choice.OCTET_STRING_SIZE_3_.buf = ver3;
  ie.extensionValue.choice.OCTET_STRING_SIZE_3_.size = 3;
  ASN_SEQUENCE_ADD(&ext.list, &ie);

  version.iE_Extensions = (void*)&ext;

  fflush(stdout);
  fflush(stderr);
  xer_fprint(stdout, &asn_DEF_RRC_Version, &version);
  fflush(stdout);
  fflush(stderr);

  void *dec;

  asn_enc_rval_t enc_ret = aper_encode_to_buffer(&asn_DEF_RRC_Version, NULL, &version, out, sizeof(out));
  if (enc_ret.encoded <= 0) printf("encode failed\n"); else printf("encode ok\n");
  printf("encoded aper[%ld]:", (enc_ret.encoded+7)/8);
  for (int i = 0; i < (enc_ret.encoded+7) / 8; i++) printf(" %2.2x", (unsigned char)out[i]);
  printf("\n");

  dec = NULL;
  asn_dec_rval_t dec_ret = asn_decode(NULL, ATS_ALIGNED_BASIC_PER, &asn_DEF_RRC_Version, &dec, out, (enc_ret.encoded+7) / 8);
  if (dec_ret.code) printf("decode failed\n"); else printf("decode ok\n");
  fflush(stdout);
  fflush(stderr);
  xer_fprint(stdout, &asn_DEF_RRC_Version, dec);
  fflush(stdout);
  fflush(stderr);

  enc_ret = uper_encode_to_buffer(&asn_DEF_RRC_Version, NULL, &version, out, sizeof(out));
  if (enc_ret.encoded <= 0) printf("encode failed\n"); else printf("encode ok\n");
  printf("encoded uper[%ld]:", (enc_ret.encoded+7)/8);
  for (int i = 0; i < (enc_ret.encoded+7) / 8; i++) printf(" %2.2x", (unsigned char)out[i]);
  printf("\n");

  dec = NULL;
  dec_ret = asn_decode(NULL, ATS_UNALIGNED_BASIC_PER, &asn_DEF_RRC_Version, &dec, out, (enc_ret.encoded+7) / 8);
  if (dec_ret.code) printf("decode failed\n"); else printf("decode ok\n");
  fflush(stdout);
  fflush(stderr);
  xer_fprint(stdout, &asn_DEF_RRC_Version, dec);
  fflush(stdout);
  fflush(stderr);

  return 0;
}
----

It encodes as following:

APER: f0 00 00 00 c7 40 04 03 11 05 01
UPER: f0 00 00 0c 74 10 0c 44 14 04

Instead of:

APER: f0 00 00 00 c7 40 03 11 05 01
UPER: f0 00 00 0c 74 0c 44 14 04

(Basically since the size is fixed, it shall not be encoded.)

Note: this commit does not solve all cases. For example the constraint:

    SIZE(3..1000000)

is not managed properly. (Solved in another commit.)

jer: Formatting enhancements

jer: Unwrapped root

jer: OCTET STRING UTF-8 add quotes

jer: INTEGER and ENUMERATED compliant decoding

jer: GraphicString missing operation definition

jer: OCTET STRING allow empty

jer: RELATIVE-OID add quotes