text: /*
   * Copyright (c) 2017 Lev Walkin <vlm@lionet.info>.
   * All rights reserved.
   * Redistribution and modifications are permitted subject to BSD license.
   */
  #include <asn_internal.h>
  #include <INTEGER.h>
  
  asn_dec_rval_t
  INTEGER_decode_aper(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_INTEGER_specifics_t *specs = (const asn_INTEGER_specifics_t *)td->specifics;
      asn_dec_rval_t rval = { RC_OK, 0 };
      INTEGER_t *st = (INTEGER_t *)*sptr;
      const asn_per_constraint_t *ct;
      int repeat;
  
      (void)opt_codec_ctx;
  
      if(!st) {
          st = (INTEGER_t *)(*sptr = CALLOC(1, sizeof(*st)));
          if(!st) ASN__DECODE_FAILED;
      }
  
      if(!constraints) constraints = td->encoding_constraints.per_constraints;
      ct = constraints ? &constraints->value : 0;
  
      if(ct && ct->flags & APC_EXTENSIBLE) {
          int inext = per_get_few_bits(pd, 1);
          if(inext < 0) ASN__DECODE_STARVED;
          if(inext) ct = 0;
      }
  
      FREEMEM(st->buf);
      st->buf = 0;
      st->size = 0;
      if(ct) {
          if(ct->flags & APC_SEMI_CONSTRAINED) {
              st->buf = (uint8_t *)CALLOC(1, 2);
              if(!st->buf) ASN__DECODE_FAILED;
              st->size = 1;
          } else if(ct->flags & APC_CONSTRAINED && ct->range_bits >= 0) {
              size_t size = (ct->range_bits + 7) >> 3;
              st->buf = (uint8_t *)MALLOC(1 + size + 1);
              if(!st->buf) ASN__DECODE_FAILED;
              st->size = size;
          }
      }
  
      /* X.691, #12.2.2 */
      if(ct && ct->flags != APC_UNCONSTRAINED) {
          /* #10.5.6 */
          ASN_DEBUG("Integer with range %d bits", ct->range_bits);
          if(ct->range_bits >= 0) {
              if (ct->range_bits > 16) {
                  int max_range_bytes = (ct->range_bits >> 3) +
                                        (((ct->range_bits % 8) > 0) ? 1 : 0);
                  int length = 0, i;
                  long value = 0;
  
                  for (i = 1; ; i++) {
                      int upper = 1 << i;
                      if (upper >= max_range_bytes)
                          break;
                  }
                  ASN_DEBUG("Can encode %d (%d bytes) in %d bits", ct->range_bits,
                            max_range_bytes, i);
  
                  if ((length = per_get_few_bits(pd, i)) < 0)
                      ASN__DECODE_FAILED;
  
                  /* X.691 #12.2.6 length determinant + lb (1) */
                  length += 1;
                  ASN_DEBUG("Got length %d", length);
                  if (aper_get_align(pd) != 0)
                      ASN__DECODE_FAILED;
                  while (length--) {
                      int buf = per_get_few_bits(pd, 8);
                      if (buf < 0)
                          ASN__DECODE_FAILED;
                      value += (((long)buf) << (8 * length));
                  }
  
                  value += ct->lower_bound;
                  if((specs && specs->field_unsigned)
                          ? asn_uint642INTEGER(st, (unsigned long)value)
                          : asn_int642INTEGER(st, value))
                      ASN__DECODE_FAILED;
                  ASN_DEBUG("Got value %ld + low %ld",
                            value, ct->lower_bound);
              } else {
                  long value = 0;
                  if (ct->range_bits < 8) {
                      value = per_get_few_bits(pd, ct->range_bits);
                      if(value < 0) ASN__DECODE_STARVED;
                  } else if (ct->range_bits == 8) {
                      if (aper_get_align(pd) < 0)
                          ASN__DECODE_FAILED;
                      value = per_get_few_bits(pd, ct->range_bits);
                      if(value < 0) ASN__DECODE_STARVED;
                  } else {
                      /* Align */
                      if (aper_get_align(pd) < 0)
                          ASN__DECODE_FAILED;
                      value = per_get_few_bits(pd, 16);
                      if(value < 0) ASN__DECODE_STARVED;
                  }
                  value += ct->lower_bound;
                  if((specs && specs->field_unsigned)
                          ? asn_ulong2INTEGER(st, value)
                          : asn_long2INTEGER(st, value))
                      ASN__DECODE_FAILED;
                  ASN_DEBUG("Got value %ld + low %ld",
                            value, ct->lower_bound);
              }
              return rval;
          } else {
              ASN__DECODE_FAILED;
          }
      } else {
          ASN_DEBUG("Decoding unconstrained integer %s", td->name);
      }
  
      /* X.691, #12.2.3, #12.2.4 */
      do {
          ssize_t len;
          void *p;
          int ret;
  
          /* Get the PER length */
          len = aper_get_length(pd, -1, -1, &repeat);
          if(len < 0) ASN__DECODE_STARVED;
  
          p = REALLOC(st->buf, st->size + len + 1);
          if(!p) ASN__DECODE_FAILED;
          st->buf = (uint8_t *)p;
  
          ret = per_get_many_bits(pd, &st->buf[st->size], 0, 8 * len);
          if(ret < 0) ASN__DECODE_STARVED;
          st->size += len;
      } while(repeat);
      st->buf[st->size] = 0;  /* JIC */
  
      /* #12.2.3 */
      if(ct && ct->lower_bound) {
          /*
           * TODO: replace by in-place arithmetics.
           */
          long value;
          if(asn_INTEGER2long(st, &value))
              ASN__DECODE_FAILED;
          if(asn_long2INTEGER(st, value + ct->lower_bound))
              ASN__DECODE_FAILED;
      }
  
      return rval;
  }
  
  asn_enc_rval_t
  INTEGER_encode_aper(const asn_TYPE_descriptor_t *td,
                      const asn_per_constraints_t *constraints,
                      const void *sptr, asn_per_outp_t *po) {
      const asn_INTEGER_specifics_t *specs = (const asn_INTEGER_specifics_t *)td->specifics;
      asn_enc_rval_t er = {0,0,0};
      const INTEGER_t *st = (const INTEGER_t *)sptr;
      const uint8_t *buf;
      const uint8_t *end;
      const asn_per_constraint_t *ct;
      long value = 0;
  
      if(!st || st->size == 0) ASN__ENCODE_FAILED;
  
      if(!constraints) constraints = td->encoding_constraints.per_constraints;
      ct = constraints ? &constraints->value : 0;
  
      er.encoded = 0;
  
      if(ct) {
          int inext = 0;
          if(specs && specs->field_unsigned) {
              unsigned long uval;
              if(asn_INTEGER2ulong(st, &uval))
                  ASN__ENCODE_FAILED;
              /* Check proper range */
              if(ct->flags & APC_SEMI_CONSTRAINED) {
                  if(uval < (unsigned long)ct->lower_bound)
                      inext = 1;
              } else if(ct->range_bits >= 0) {
                  if(uval < (unsigned long)ct->lower_bound
                          || uval > (unsigned long)ct->upper_bound)
                      inext = 1;
              }
              ASN_DEBUG("Value %lu (%02x/%lu) lb %ld ub %ld %s",
                        uval, st->buf[0], st->size,
                        ct->lower_bound, ct->upper_bound,
                        inext ? "ext" : "fix");
              value = uval;
          } else {
              if(asn_INTEGER2long(st, &value)) ASN__ENCODE_FAILED;
              /* Check proper range */
              if(ct->flags & APC_SEMI_CONSTRAINED) {
                  if(value < ct->lower_bound)
                      inext = 1;
              } else if(ct->range_bits >= 0) {
                  if(value < ct->lower_bound
                          || value > ct->upper_bound)
                      inext = 1;
              }
              ASN_DEBUG("Value %lu (%02x/%lu) lb %ld ub %ld %s",
                        value, st->buf[0], st->size,
                        ct->lower_bound, ct->upper_bound,
                        inext ? "ext" : "fix");
          }
          if(ct->flags & APC_EXTENSIBLE) {
              if(per_put_few_bits(po, inext, 1))
                  ASN__ENCODE_FAILED;
              if(inext) ct = 0;
          } else if(inext) {
              ASN__ENCODE_FAILED;
          }
      }
  
      /* X.691, #12.2.2 */
      if(ct && ct->range_bits >= 0) {
          unsigned long v;
  
          /* #10.5.6 */
          ASN_DEBUG("Encoding integer %ld (%lu) with range %d bits",
                    value, value - ct->lower_bound, ct->range_bits);
  
          v = value - ct->lower_bound;
  
          /* #12 <= 8 -> alignment ? */
          int range = ct->upper_bound - ct->lower_bound + 1;
          if (ct->range_bits < 8 || (ct->range_bits == 8 && range < 256)) {
              if(per_put_few_bits(po, 0x00 | v, ct->range_bits))
                  ASN__ENCODE_FAILED;
          } else if (ct->range_bits == 8) {
              if(aper_put_align(po) < 0)
                  ASN__ENCODE_FAILED;
              if(per_put_few_bits(po, 0x00 | v, ct->range_bits))
                  ASN__ENCODE_FAILED;
          } else if (ct->range_bits <= 16) {
              /* Consume the bytes to align on octet */
              if(aper_put_align(po) < 0)
                  ASN__ENCODE_FAILED;
              if(per_put_few_bits(po, 0x0000 | v, 16))
                  ASN__ENCODE_FAILED;
          } else {
              /* TODO: extend to >64 bits */
              int64_t v64 = v;
              int i, j;
              int max_range_bytes = (ct->range_bits >> 3) +
                                    (((ct->range_bits % 8) > 0) ? 1 : 0);
  
              for (i = 1; ; i++) {
                  int upper = 1 << i;
                  if (upper >= max_range_bytes)
                      break;
              }
  
              for (j = sizeof(int64_t) -1; j != 0; j--) {
                  int64_t val;
                  val = v64 >> (j * 8);
                  if (val != 0)
                      break;
              }
  
              /* Putting length in the minimum number of bits ex: 5 = 3bits */
              if (per_put_few_bits(po, j, i))
                  ASN__ENCODE_FAILED;
  
              /* Consume the bits to align on octet */
              if (aper_put_align(po) < 0)
                  ASN__ENCODE_FAILED;
              /* Put the value */
              for (i = 0; i <= j; i++) {
                  if(per_put_few_bits(po, (v64 >> (8 * (j - i))) & 0xff, 8))
                      ASN__ENCODE_FAILED;
              }
          }
          ASN__ENCODED_OK(er);
      }
  
      if(ct && ct->lower_bound) {
          ASN_DEBUG("Adjust lower bound to %ld", ct->lower_bound);
          /* TODO: adjust lower bound */
          ASN__ENCODE_FAILED;
      }
  
      for(buf = st->buf, end = st->buf + st->size; buf < end;) {
          int need_eom = 0;
          ssize_t mayEncode = aper_put_length(po, -1, end - buf, &need_eom);
          if(mayEncode < 0)
              ASN__ENCODE_FAILED;
          if(per_put_many_bits(po, buf, 8 * mayEncode))
              ASN__ENCODE_FAILED;
          buf += mayEncode;
          if(need_eom && aper_put_length(po, -1, 0, 0)) ASN__ENCODE_FAILED;
      }
  
      ASN__ENCODED_OK(er);
  }
  