| /*- |
| * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved. |
| * Redistribution and modifications are permitted subject to BSD license. |
| */ |
| #include <asn_internal.h> |
| #include <BIT_STRING.h> |
| #include <asn_internal.h> |
| |
| /* |
| * BIT STRING basic type description. |
| */ |
| static const ber_tlv_tag_t asn_DEF_BIT_STRING_tags[] = { |
| (ASN_TAG_CLASS_UNIVERSAL | (3 << 2)) |
| }; |
| asn_OCTET_STRING_specifics_t asn_SPC_BIT_STRING_specs = { |
| sizeof(BIT_STRING_t), |
| offsetof(BIT_STRING_t, _asn_ctx), |
| ASN_OSUBV_BIT |
| }; |
| asn_TYPE_operation_t asn_OP_BIT_STRING = { |
| OCTET_STRING_free, /* Implemented in terms of OCTET STRING */ |
| BIT_STRING_print, |
| BIT_STRING_compare, |
| OCTET_STRING_decode_ber, /* Implemented in terms of OCTET STRING */ |
| OCTET_STRING_encode_der, /* Implemented in terms of OCTET STRING */ |
| OCTET_STRING_decode_xer_binary, |
| BIT_STRING_encode_xer, |
| #ifdef ASN_DISABLE_OER_SUPPORT |
| 0, |
| 0, |
| #else |
| BIT_STRING_decode_oer, |
| BIT_STRING_encode_oer, |
| #endif /* ASN_DISABLE_OER_SUPPORT */ |
| #ifdef ASN_DISABLE_PER_SUPPORT |
| 0, |
| 0, |
| 0, |
| 0, |
| #else |
| BIT_STRING_decode_uper, /* Unaligned PER decoder */ |
| BIT_STRING_encode_uper, /* Unaligned PER encoder */ |
| OCTET_STRING_decode_aper, /* Aligned PER decoder */ |
| OCTET_STRING_encode_aper, /* Aligned PER encoder */ |
| #endif /* ASN_DISABLE_PER_SUPPORT */ |
| BIT_STRING_random_fill, |
| 0 /* Use generic outmost tag fetcher */ |
| }; |
| asn_TYPE_descriptor_t asn_DEF_BIT_STRING = { |
| "BIT STRING", |
| "BIT_STRING", |
| &asn_OP_BIT_STRING, |
| asn_DEF_BIT_STRING_tags, |
| sizeof(asn_DEF_BIT_STRING_tags) |
| / sizeof(asn_DEF_BIT_STRING_tags[0]), |
| asn_DEF_BIT_STRING_tags, /* Same as above */ |
| sizeof(asn_DEF_BIT_STRING_tags) |
| / sizeof(asn_DEF_BIT_STRING_tags[0]), |
| { 0, 0, BIT_STRING_constraint }, |
| 0, 0, /* No members */ |
| &asn_SPC_BIT_STRING_specs |
| }; |
| |
| /* |
| * BIT STRING generic constraint. |
| */ |
| int |
| BIT_STRING_constraint(const asn_TYPE_descriptor_t *td, const void *sptr, |
| asn_app_constraint_failed_f *ctfailcb, void *app_key) { |
| const BIT_STRING_t *st = (const BIT_STRING_t *)sptr; |
| |
| if(st && st->buf) { |
| if((st->size == 0 && st->bits_unused) |
| || st->bits_unused < 0 || st->bits_unused > 7) { |
| ASN__CTFAIL(app_key, td, sptr, |
| "%s: invalid padding byte (%s:%d)", |
| td->name, __FILE__, __LINE__); |
| return -1; |
| } |
| } else { |
| ASN__CTFAIL(app_key, td, sptr, |
| "%s: value not given (%s:%d)", |
| td->name, __FILE__, __LINE__); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static const char *_bit_pattern[16] = { |
| "0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", |
| "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111" |
| }; |
| |
| asn_enc_rval_t |
| BIT_STRING_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) { |
| asn_enc_rval_t er = {0, 0, 0}; |
| char scratch[128]; |
| char *p = scratch; |
| char *scend = scratch + (sizeof(scratch) - 10); |
| const BIT_STRING_t *st = (const BIT_STRING_t *)sptr; |
| int xcan = (flags & XER_F_CANONICAL); |
| uint8_t *buf; |
| uint8_t *end; |
| |
| if(!st || !st->buf) |
| ASN__ENCODE_FAILED; |
| |
| er.encoded = 0; |
| |
| buf = st->buf; |
| end = buf + st->size - 1; /* Last byte is special */ |
| |
| /* |
| * Binary dump |
| */ |
| for(; buf < end; buf++) { |
| int v = *buf; |
| int nline = xcan?0:(((buf - st->buf) % 8) == 0); |
| if(p >= scend || nline) { |
| ASN__CALLBACK(scratch, p - scratch); |
| p = scratch; |
| if(nline) ASN__TEXT_INDENT(1, ilevel); |
| } |
| memcpy(p + 0, _bit_pattern[v >> 4], 4); |
| memcpy(p + 4, _bit_pattern[v & 0x0f], 4); |
| p += 8; |
| } |
| |
| if(!xcan && ((buf - st->buf) % 8) == 0) |
| ASN__TEXT_INDENT(1, ilevel); |
| ASN__CALLBACK(scratch, p - scratch); |
| p = scratch; |
| |
| if(buf == end) { |
| int v = *buf; |
| int ubits = st->bits_unused; |
| int i; |
| for(i = 7; i >= ubits; i--) |
| *p++ = (v & (1 << i)) ? 0x31 : 0x30; |
| ASN__CALLBACK(scratch, p - scratch); |
| } |
| |
| if(!xcan) ASN__TEXT_INDENT(1, ilevel - 1); |
| |
| ASN__ENCODED_OK(er); |
| cb_failed: |
| ASN__ENCODE_FAILED; |
| } |
| |
| |
| /* |
| * BIT STRING specific contents printer. |
| */ |
| int |
| BIT_STRING_print(const asn_TYPE_descriptor_t *td, const void *sptr, int ilevel, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| const char * const h2c = "0123456789ABCDEF"; |
| char scratch[64]; |
| const BIT_STRING_t *st = (const BIT_STRING_t *)sptr; |
| uint8_t *buf; |
| uint8_t *end; |
| char *p = scratch; |
| |
| (void)td; /* Unused argument */ |
| |
| if(!st || !st->buf) |
| return (cb("<absent>", 8, app_key) < 0) ? -1 : 0; |
| |
| ilevel++; |
| buf = st->buf; |
| end = buf + st->size; |
| |
| /* |
| * Hexadecimal dump. |
| */ |
| for(; buf < end; buf++) { |
| if((buf - st->buf) % 16 == 0 && (st->size > 16) |
| && buf != st->buf) { |
| _i_INDENT(1); |
| /* Dump the string */ |
| if(cb(scratch, p - scratch, app_key) < 0) return -1; |
| p = scratch; |
| } |
| *p++ = h2c[*buf >> 4]; |
| *p++ = h2c[*buf & 0x0F]; |
| *p++ = 0x20; |
| } |
| |
| if(p > scratch) { |
| p--; /* Eat the tailing space */ |
| |
| if((st->size > 16)) { |
| _i_INDENT(1); |
| } |
| |
| /* Dump the incomplete 16-bytes row */ |
| if(cb(scratch, p - scratch, app_key) < 0) |
| return -1; |
| } |
| |
| if(st->bits_unused) { |
| int ret = snprintf(scratch, sizeof(scratch), " (%d bit%s unused)", |
| st->bits_unused, st->bits_unused == 1 ? "" : "s"); |
| assert(ret > 0 && ret < (ssize_t)sizeof(scratch)); |
| if(ret > 0 && ret < (ssize_t)sizeof(scratch) |
| && cb(scratch, ret, app_key) < 0) |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Non-destructively remove the trailing 0-bits from the given bit string. |
| */ |
| static const BIT_STRING_t * |
| BIT_STRING__compactify(const BIT_STRING_t *st, BIT_STRING_t *tmp) { |
| const uint8_t *b; |
| union { |
| const uint8_t *c_buf; |
| uint8_t *nc_buf; |
| } unconst; |
| |
| if(st->size == 0) { |
| assert(st->bits_unused == 0); |
| return st; |
| } else { |
| for(b = &st->buf[st->size - 1]; b > st->buf && *b == 0; b--) { |
| ; |
| } |
| /* b points to the last byte which may contain data */ |
| if(*b) { |
| int unused = 7; |
| uint8_t v = *b; |
| v &= -(int8_t)v; |
| if(v & 0x0F) unused -= 4; |
| if(v & 0x33) unused -= 2; |
| if(v & 0x55) unused -= 1; |
| tmp->size = b-st->buf + 1; |
| tmp->bits_unused = unused; |
| } else { |
| tmp->size = b-st->buf; |
| tmp->bits_unused = 0; |
| } |
| |
| assert(b >= st->buf); |
| } |
| |
| unconst.c_buf = st->buf; |
| tmp->buf = unconst.nc_buf; |
| return tmp; |
| } |
| |
| /* |
| * Lexicographically compare the common prefix of both strings, |
| * and if it is the same return -1 for the smallest string. |
| */ |
| int |
| BIT_STRING_compare(const asn_TYPE_descriptor_t *td, const void *aptr, |
| const void *bptr) { |
| /* |
| * Remove information about trailing bits, since |
| * X.680 (08/2015) #22.7 "ensure that different semantics are not" |
| * "associated with [values that differ only in] the trailing 0 bits." |
| */ |
| BIT_STRING_t compact_a, compact_b; |
| const BIT_STRING_t *a = BIT_STRING__compactify(aptr, &compact_a); |
| const BIT_STRING_t *b = BIT_STRING__compactify(bptr, &compact_b); |
| const asn_OCTET_STRING_specifics_t *specs = td->specifics; |
| |
| assert(specs && specs->subvariant == ASN_OSUBV_BIT); |
| |
| if(a && b) { |
| size_t common_prefix_size = a->size <= b->size ? a->size : b->size; |
| int ret = memcmp(a->buf, b->buf, common_prefix_size); |
| if(ret == 0) { |
| /* Figure out which string with equal prefixes is longer. */ |
| if(a->size < b->size) { |
| return -1; |
| } else if(a->size > b->size) { |
| return 1; |
| } else { |
| /* Figure out how many unused bits */ |
| if(a->bits_unused > b->bits_unused) { |
| return -1; |
| } else if(a->bits_unused < b->bits_unused) { |
| return 1; |
| } else { |
| return 0; |
| } |
| } |
| } else { |
| return ret; |
| } |
| } else if(!a && !b) { |
| return 0; |
| } else if(!a) { |
| return -1; |
| } else { |
| return 1; |
| } |
| } |
| |
| #ifndef ASN_DISABLE_PER_SUPPORT |
| |
| #undef RETURN |
| #define RETURN(_code) \ |
| do { \ |
| asn_dec_rval_t tmprval; \ |
| tmprval.code = _code; \ |
| tmprval.consumed = consumed_myself; \ |
| return tmprval; \ |
| } while(0) |
| |
| static asn_per_constraint_t asn_DEF_BIT_STRING_constraint_size = { |
| APC_SEMI_CONSTRAINED, -1, -1, 0, 0}; |
| |
| asn_dec_rval_t |
| BIT_STRING_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_OCTET_STRING_specifics_t *specs = td->specifics |
| ? (const asn_OCTET_STRING_specifics_t *)td->specifics |
| : &asn_SPC_BIT_STRING_specs; |
| const asn_per_constraints_t *pc = |
| constraints ? constraints : td->encoding_constraints.per_constraints; |
| const asn_per_constraint_t *csiz; |
| asn_dec_rval_t rval = { RC_OK, 0 }; |
| BIT_STRING_t *st = (BIT_STRING_t *)*sptr; |
| ssize_t consumed_myself = 0; |
| int repeat; |
| |
| (void)opt_codec_ctx; |
| |
| if(pc) { |
| csiz = &pc->size; |
| } else { |
| csiz = &asn_DEF_BIT_STRING_constraint_size; |
| } |
| |
| if(specs->subvariant != ASN_OSUBV_BIT) { |
| ASN_DEBUG("Subvariant %d is not BIT OSUBV_BIT", specs->subvariant); |
| RETURN(RC_FAIL); |
| } |
| |
| /* |
| * Allocate the string. |
| */ |
| if(!st) { |
| st = (BIT_STRING_t *)(*sptr = CALLOC(1, specs->struct_size)); |
| if(!st) RETURN(RC_FAIL); |
| } |
| |
| ASN_DEBUG("PER Decoding %s size %ld .. %ld bits %d", |
| csiz->flags & APC_EXTENSIBLE ? "extensible" : "non-extensible", |
| csiz->lower_bound, csiz->upper_bound, csiz->effective_bits); |
| |
| if(csiz->flags & APC_EXTENSIBLE) { |
| int inext = per_get_few_bits(pd, 1); |
| if(inext < 0) RETURN(RC_WMORE); |
| if(inext) { |
| csiz = &asn_DEF_BIT_STRING_constraint_size; |
| } |
| } |
| |
| if(csiz->effective_bits >= 0) { |
| FREEMEM(st->buf); |
| st->size = (csiz->upper_bound + 7) >> 3; |
| st->buf = (uint8_t *)MALLOC(st->size + 1); |
| if(!st->buf) { st->size = 0; RETURN(RC_FAIL); } |
| } |
| |
| /* X.691, #16.5: zero-length encoding */ |
| /* X.691, #16.6: short fixed length encoding (up to 2 octets) */ |
| /* X.691, #16.7: long fixed length encoding (up to 64K octets) */ |
| if(csiz->effective_bits == 0) { |
| int ret; |
| ASN_DEBUG("Encoding BIT STRING size %ld", csiz->upper_bound); |
| ret = per_get_many_bits(pd, st->buf, 0, csiz->upper_bound); |
| if(ret < 0) RETURN(RC_WMORE); |
| consumed_myself += csiz->upper_bound; |
| st->buf[st->size] = 0; |
| st->bits_unused = (8 - (csiz->upper_bound & 0x7)) & 0x7; |
| RETURN(RC_OK); |
| } |
| |
| st->size = 0; |
| do { |
| ssize_t raw_len; |
| ssize_t len_bytes; |
| ssize_t len_bits; |
| void *p; |
| int ret; |
| |
| /* Get the PER length */ |
| raw_len = uper_get_length(pd, csiz->effective_bits, csiz->lower_bound, |
| &repeat); |
| if(raw_len < 0) RETURN(RC_WMORE); |
| if(raw_len == 0 && st->buf) break; |
| |
| ASN_DEBUG("Got PER length eb %ld, len %ld, %s (%s)", |
| (long)csiz->effective_bits, (long)raw_len, |
| repeat ? "repeat" : "once", td->name); |
| len_bits = raw_len; |
| len_bytes = (len_bits + 7) >> 3; |
| if(len_bits & 0x7) st->bits_unused = 8 - (len_bits & 0x7); |
| /* len_bits be multiple of 16K if repeat is set */ |
| p = REALLOC(st->buf, st->size + len_bytes + 1); |
| if(!p) RETURN(RC_FAIL); |
| st->buf = (uint8_t *)p; |
| |
| ret = per_get_many_bits(pd, &st->buf[st->size], 0, len_bits); |
| if(ret < 0) RETURN(RC_WMORE); |
| st->size += len_bytes; |
| } while(repeat); |
| st->buf[st->size] = 0; /* nul-terminate */ |
| |
| return rval; |
| } |
| |
| asn_enc_rval_t |
| BIT_STRING_encode_uper(const asn_TYPE_descriptor_t *td, |
| const asn_per_constraints_t *constraints, |
| const void *sptr, asn_per_outp_t *po) { |
| const asn_OCTET_STRING_specifics_t *specs = |
| td->specifics ? (const asn_OCTET_STRING_specifics_t *)td->specifics |
| : &asn_SPC_BIT_STRING_specs; |
| const asn_per_constraints_t *pc = |
| constraints ? constraints : td->encoding_constraints.per_constraints; |
| const asn_per_constraint_t *csiz; |
| const BIT_STRING_t *st = (const BIT_STRING_t *)sptr; |
| BIT_STRING_t compact_bstr; /* Do not modify this directly! */ |
| asn_enc_rval_t er = { 0, 0, 0 }; |
| int inext = 0; /* Lies not within extension root */ |
| size_t size_in_bits; |
| const uint8_t *buf; |
| int ret; |
| int ct_extensible; |
| |
| if(!st || (!st->buf && st->size)) |
| ASN__ENCODE_FAILED; |
| |
| if(specs->subvariant == ASN_OSUBV_BIT) { |
| if((st->size == 0 && st->bits_unused) || (st->bits_unused & ~7)) |
| ASN__ENCODE_FAILED; |
| } else { |
| ASN__ENCODE_FAILED; |
| } |
| |
| if(pc) { |
| csiz = &pc->size; |
| } else { |
| csiz = &asn_DEF_BIT_STRING_constraint_size; |
| } |
| ct_extensible = csiz->flags & APC_EXTENSIBLE; |
| |
| /* Figure out the size without the trailing bits */ |
| st = BIT_STRING__compactify(st, &compact_bstr); |
| size_in_bits = 8 * st->size - st->bits_unused; |
| |
| ASN_DEBUG( |
| "Encoding %s into %" ASN_PRI_SIZE " bits" |
| " (%ld..%ld, effective %d)%s", |
| td->name, size_in_bits, csiz->lower_bound, csiz->upper_bound, |
| csiz->effective_bits, ct_extensible ? " EXT" : ""); |
| |
| /* Figure out whether size lies within PER visible constraint */ |
| |
| if(csiz->effective_bits >= 0) { |
| if((ssize_t)size_in_bits > csiz->upper_bound) { |
| if(ct_extensible) { |
| csiz = &asn_DEF_BIT_STRING_constraint_size; |
| inext = 1; |
| } else { |
| ASN__ENCODE_FAILED; |
| } |
| } |
| } else { |
| inext = 0; |
| } |
| |
| if(ct_extensible) { |
| /* Declare whether length is [not] within extension root */ |
| if(per_put_few_bits(po, inext, 1)) |
| ASN__ENCODE_FAILED; |
| } |
| |
| if(csiz->effective_bits >= 0 && !inext) { |
| int add_trailer = (ssize_t)size_in_bits < csiz->lower_bound; |
| ASN_DEBUG( |
| "Encoding %" ASN_PRI_SIZE " bytes (%ld), length (in %d bits) trailer %d; actual " |
| "value %" ASN_PRI_SSIZE "", |
| st->size, size_in_bits - csiz->lower_bound, csiz->effective_bits, |
| add_trailer, |
| add_trailer ? 0 : (ssize_t)size_in_bits - csiz->lower_bound); |
| ret = per_put_few_bits( |
| po, add_trailer ? 0 : (ssize_t)size_in_bits - csiz->lower_bound, |
| csiz->effective_bits); |
| if(ret) ASN__ENCODE_FAILED; |
| ret = per_put_many_bits(po, st->buf, size_in_bits); |
| if(ret) ASN__ENCODE_FAILED; |
| if(add_trailer) { |
| static const uint8_t zeros[16]; |
| size_t trailing_zero_bits = csiz->lower_bound - size_in_bits; |
| while(trailing_zero_bits > 0) { |
| if(trailing_zero_bits > 8 * sizeof(zeros)) { |
| ret = per_put_many_bits(po, zeros, 8 * sizeof(zeros)); |
| trailing_zero_bits -= 8 * sizeof(zeros); |
| } else { |
| ret = per_put_many_bits(po, zeros, trailing_zero_bits); |
| trailing_zero_bits = 0; |
| } |
| if(ret) ASN__ENCODE_FAILED; |
| } |
| } |
| ASN__ENCODED_OK(er); |
| } |
| |
| ASN_DEBUG("Encoding %" ASN_PRI_SIZE " bytes", st->size); |
| |
| buf = st->buf; |
| do { |
| int need_eom = 0; |
| ssize_t maySave = uper_put_length(po, size_in_bits, &need_eom); |
| if(maySave < 0) ASN__ENCODE_FAILED; |
| |
| ASN_DEBUG("Encoding %" ASN_PRI_SSIZE " of %" ASN_PRI_SIZE "", maySave, size_in_bits); |
| |
| ret = per_put_many_bits(po, buf, maySave); |
| if(ret) ASN__ENCODE_FAILED; |
| |
| buf += maySave >> 3; |
| size_in_bits -= maySave; |
| assert(!(maySave & 0x07) || !size_in_bits); |
| if(need_eom && uper_put_length(po, 0, 0)) |
| ASN__ENCODE_FAILED; /* End of Message length */ |
| } while(size_in_bits); |
| |
| ASN__ENCODED_OK(er); |
| } |
| |
| #endif /* ASN_DISABLE_PER_SUPPORT */ |
| |
| asn_random_fill_result_t |
| BIT_STRING_random_fill(const asn_TYPE_descriptor_t *td, void **sptr, |
| const asn_encoding_constraints_t *constraints, |
| size_t max_length) { |
| const asn_OCTET_STRING_specifics_t *specs = |
| td->specifics ? (const asn_OCTET_STRING_specifics_t *)td->specifics |
| : &asn_SPC_BIT_STRING_specs; |
| asn_random_fill_result_t result_ok = {ARFILL_OK, 1}; |
| asn_random_fill_result_t result_failed = {ARFILL_FAILED, 0}; |
| asn_random_fill_result_t result_skipped = {ARFILL_SKIPPED, 0}; |
| static unsigned lengths[] = {0, 1, 2, 3, 4, 8, |
| 126, 127, 128, 16383, 16384, 16385, |
| 65534, 65535, 65536, 65537}; |
| uint8_t *buf; |
| uint8_t *bend; |
| uint8_t *b; |
| size_t rnd_bits, rnd_len; |
| BIT_STRING_t *st; |
| |
| if(max_length == 0) return result_skipped; |
| |
| switch(specs->subvariant) { |
| case ASN_OSUBV_ANY: |
| return result_failed; |
| case ASN_OSUBV_BIT: |
| break; |
| default: |
| break; |
| } |
| |
| /* Figure out how far we should go */ |
| rnd_bits = lengths[asn_random_between( |
| 0, sizeof(lengths) / sizeof(lengths[0]) - 1)]; |
| if(!constraints || !constraints->per_constraints) |
| constraints = &td->encoding_constraints; |
| if(constraints->per_constraints) { |
| const asn_per_constraint_t *pc = &constraints->per_constraints->size; |
| if(pc->flags & APC_CONSTRAINED) { |
| long suggested_upper_bound = pc->upper_bound < (ssize_t)max_length |
| ? pc->upper_bound |
| : (ssize_t)max_length; |
| if(max_length < (size_t)pc->lower_bound) { |
| return result_skipped; |
| } |
| if(pc->flags & APC_EXTENSIBLE) { |
| switch(asn_random_between(0, 5)) { |
| case 0: |
| if(pc->lower_bound > 0) { |
| rnd_bits = pc->lower_bound - 1; |
| break; |
| } |
| /* Fall through */ |
| case 1: |
| rnd_bits = pc->upper_bound + 1; |
| break; |
| case 2: |
| /* Keep rnd_bits from the table */ |
| if(rnd_bits < max_length) { |
| break; |
| } |
| /* Fall through */ |
| default: |
| rnd_bits = asn_random_between(pc->lower_bound, |
| suggested_upper_bound); |
| } |
| } else { |
| rnd_bits = |
| asn_random_between(pc->lower_bound, suggested_upper_bound); |
| } |
| } else { |
| rnd_bits = asn_random_between(0, max_length - 1); |
| } |
| } else if(rnd_bits >= max_length) { |
| rnd_bits = asn_random_between(0, max_length - 1); |
| } |
| |
| rnd_len = (rnd_bits + 7) / 8; |
| buf = CALLOC(1, rnd_len + 1); |
| if(!buf) return result_failed; |
| |
| bend = &buf[rnd_len]; |
| |
| for(b = buf; b < bend; b++) { |
| *(uint8_t *)b = asn_random_between(0, 255); |
| } |
| *b = 0; /* Zero-terminate just in case. */ |
| |
| if(*sptr) { |
| st = *sptr; |
| FREEMEM(st->buf); |
| } else { |
| st = (BIT_STRING_t *)(*sptr = CALLOC(1, specs->struct_size)); |
| if(!st) { |
| FREEMEM(buf); |
| return result_failed; |
| } |
| } |
| |
| st->buf = buf; |
| st->size = rnd_len; |
| st->bits_unused = (8 - (rnd_bits & 0x7)) & 0x7; |
| if(st->bits_unused) { |
| assert(st->size > 0); |
| st->buf[st->size-1] &= 0xff << st->bits_unused; |
| } |
| |
| result_ok.length = st->size; |
| return result_ok; |
| } |