+++ /dev/null
-
-/*
- * Copyright (c) 2005-2017 Lev Walkin <vlm@lionet.info>.
- * All rights reserved.
- * Redistribution and modifications are permitted subject to BSD license.
- */
-#include <asn_system.h>
-#include <asn_internal.h>
-#include <asn_bit_data.h>
-
-/*
- * Create a contiguous non-refillable bit data structure.
- * Can be freed by FREEMEM().
- */
-asn_bit_data_t *
-asn_bit_data_new_contiguous(const void *data, size_t size_bits) {
- size_t size_bytes = (size_bits + 7) / 8;
- asn_bit_data_t *pd;
- uint8_t *bytes;
-
- /* Get the extensions map */
- pd = CALLOC(1, sizeof(*pd) + size_bytes + 1);
- if(!pd) {
- return NULL;
- }
- bytes = (void *)(((char *)pd) + sizeof(*pd));
- memcpy(bytes, data, size_bytes);
- bytes[size_bytes] = 0;
- pd->buffer = bytes;
- pd->nboff = 0;
- pd->nbits = size_bits;
-
- return pd;
-}
-
-
-char *
-asn_bit_data_string(asn_bit_data_t *pd) {
- static char buf[2][32];
- static int n;
- n = (n+1) % 2;
- snprintf(buf[n], sizeof(buf[n]),
- "{m=%" ASN_PRI_SIZE " span %" ASN_PRI_SIZE "[%" ASN_PRI_SIZE
- "..%" ASN_PRI_SIZE "] (%" ASN_PRI_SIZE ")}",
- pd->moved, ((uintptr_t)(pd->buffer) & 0xf), pd->nboff, pd->nbits,
- pd->nbits - pd->nboff);
- return buf[n];
-}
-
-void
-asn_get_undo(asn_bit_data_t *pd, int nbits) {
- if((ssize_t)pd->nboff < nbits) {
- assert((ssize_t)pd->nboff < nbits);
- } else {
- pd->nboff -= nbits;
- pd->moved -= nbits;
- }
-}
-
-/*
- * Extract a small number of bits (<= 31) from the specified PER data pointer.
- */
-int32_t
-asn_get_few_bits(asn_bit_data_t *pd, int nbits) {
- size_t off; /* Next after last bit offset */
- ssize_t nleft; /* Number of bits left in this stream */
- uint32_t accum;
- const uint8_t *buf;
-
- if(nbits < 0)
- return -1;
-
- nleft = pd->nbits - pd->nboff;
- if(nbits > nleft) {
- int32_t tailv, vhead;
- if(!pd->refill || nbits > 31) return -1;
- /* Accumulate unused bytes before refill */
- ASN_DEBUG("Obtain the rest %d bits (want %d)",
- (int)nleft, (int)nbits);
- tailv = asn_get_few_bits(pd, nleft);
- if(tailv < 0) return -1;
- /* Refill (replace pd contents with new data) */
- if(pd->refill(pd))
- return -1;
- nbits -= nleft;
- vhead = asn_get_few_bits(pd, nbits);
- /* Combine the rest of previous pd with the head of new one */
- tailv = (tailv << nbits) | vhead; /* Could == -1 */
- return tailv;
- }
-
- /*
- * Normalize position indicator.
- */
- if(pd->nboff >= 8) {
- pd->buffer += (pd->nboff >> 3);
- pd->nbits -= (pd->nboff & ~0x07);
- pd->nboff &= 0x07;
- }
- pd->moved += nbits;
- pd->nboff += nbits;
- off = pd->nboff;
- buf = pd->buffer;
-
- /*
- * Extract specified number of bits.
- */
- if(off <= 8)
- accum = nbits ? (buf[0]) >> (8 - off) : 0;
- else if(off <= 16)
- accum = ((buf[0] << 8) + buf[1]) >> (16 - off);
- else if(off <= 24)
- accum = ((buf[0] << 16) + (buf[1] << 8) + buf[2]) >> (24 - off);
- else if(off <= 31)
- accum = (((uint32_t)buf[0] << 24) + (buf[1] << 16)
- + (buf[2] << 8) + (buf[3])) >> (32 - off);
- else if(nbits <= 31) {
- asn_bit_data_t tpd = *pd;
- /* Here are we with our 31-bits limit plus 1..7 bits offset. */
- asn_get_undo(&tpd, nbits);
- /* The number of available bits in the stream allow
- * for the following operations to take place without
- * invoking the ->refill() function */
- accum = asn_get_few_bits(&tpd, nbits - 24) << 24;
- accum |= asn_get_few_bits(&tpd, 24);
- } else {
- asn_get_undo(pd, nbits);
- return -1;
- }
-
- accum &= (((uint32_t)1 << nbits) - 1);
-
- ASN_DEBUG(" [PER got %2d<=%2d bits => span %d %+ld[%d..%d]:%02x (%d) => 0x%x]",
- (int)nbits, (int)nleft,
- (int)pd->moved,
- (((long)pd->buffer) & 0xf),
- (int)pd->nboff, (int)pd->nbits,
- ((pd->buffer != NULL)?pd->buffer[0]:0),
- (int)(pd->nbits - pd->nboff),
- (int)accum);
-
- return accum;
-}
-
-/*
- * Extract a large number of bits from the specified PER data pointer.
- */
-int
-asn_get_many_bits(asn_bit_data_t *pd, uint8_t *dst, int alright, int nbits) {
- int32_t value;
-
- if(alright && (nbits & 7)) {
- /* Perform right alignment of a first few bits */
- value = asn_get_few_bits(pd, nbits & 0x07);
- if(value < 0) return -1;
- *dst++ = value; /* value is already right-aligned */
- nbits &= ~7;
- }
-
- while(nbits) {
- if(nbits >= 24) {
- value = asn_get_few_bits(pd, 24);
- if(value < 0) return -1;
- *(dst++) = value >> 16;
- *(dst++) = value >> 8;
- *(dst++) = value;
- nbits -= 24;
- } else {
- value = asn_get_few_bits(pd, nbits);
- if(value < 0) return -1;
- if(nbits & 7) { /* implies left alignment */
- value <<= 8 - (nbits & 7),
- nbits += 8 - (nbits & 7);
- if(nbits > 24)
- *dst++ = value >> 24;
- }
- if(nbits > 16)
- *dst++ = value >> 16;
- if(nbits > 8)
- *dst++ = value >> 8;
- *dst++ = value;
- break;
- }
- }
-
- return 0;
-}
-
-/*
- * Put a small number of bits (<= 31).
- */
-int
-asn_put_few_bits(asn_bit_outp_t *po, uint32_t bits, int obits) {
- size_t off; /* Next after last bit offset */
- size_t omsk; /* Existing last byte meaningful bits mask */
- uint8_t *buf;
-
- if(obits <= 0 || obits >= 32) return obits ? -1 : 0;
-
- ASN_DEBUG("[PER put %d bits %x to %p+%d bits]",
- obits, (int)bits, (void *)po->buffer, (int)po->nboff);
-
- /*
- * Normalize position indicator.
- */
- if(po->nboff >= 8) {
- po->buffer += (po->nboff >> 3);
- po->nbits -= (po->nboff & ~0x07);
- po->nboff &= 0x07;
- }
-
- /*
- * Flush whole-bytes output, if necessary.
- */
- if(po->nboff + obits > po->nbits) {
- size_t complete_bytes;
- if(!po->buffer) po->buffer = po->tmpspace;
- complete_bytes = (po->buffer - po->tmpspace);
- ASN_DEBUG("[PER output %ld complete + %ld]",
- (long)complete_bytes, (long)po->flushed_bytes);
- if(po->output(po->tmpspace, complete_bytes, po->op_key) < 0)
- return -1;
- if(po->nboff)
- po->tmpspace[0] = po->buffer[0];
- po->buffer = po->tmpspace;
- po->nbits = 8 * sizeof(po->tmpspace);
- po->flushed_bytes += complete_bytes;
- }
-
- /*
- * Now, due to sizeof(tmpspace), we are guaranteed large enough space.
- */
- buf = po->buffer;
- omsk = ~((1 << (8 - po->nboff)) - 1);
- off = (po->nboff + obits);
-
- /* Clear data of debris before meaningful bits */
- bits &= (((uint32_t)1 << obits) - 1);
-
- ASN_DEBUG("[PER out %d %u/%x (t=%d,o=%d) %x&%x=%x]", obits,
- (int)bits, (int)bits,
- (int)po->nboff, (int)off,
- buf[0], (int)(omsk&0xff),
- (int)(buf[0] & omsk));
-
- if(off <= 8) /* Completely within 1 byte */
- po->nboff = off,
- bits <<= (8 - off),
- buf[0] = (buf[0] & omsk) | bits;
- else if(off <= 16)
- po->nboff = off,
- bits <<= (16 - off),
- buf[0] = (buf[0] & omsk) | (bits >> 8),
- buf[1] = bits;
- else if(off <= 24)
- po->nboff = off,
- bits <<= (24 - off),
- buf[0] = (buf[0] & omsk) | (bits >> 16),
- buf[1] = bits >> 8,
- buf[2] = bits;
- else if(off <= 31)
- po->nboff = off,
- bits <<= (32 - off),
- buf[0] = (buf[0] & omsk) | (bits >> 24),
- buf[1] = bits >> 16,
- buf[2] = bits >> 8,
- buf[3] = bits;
- else {
- if(asn_put_few_bits(po, bits >> (obits - 24), 24)) return -1;
- if(asn_put_few_bits(po, bits, obits - 24)) return -1;
- }
-
- ASN_DEBUG("[PER out %u/%x => %02x buf+%ld]",
- (int)bits, (int)bits, buf[0],
- (long)(po->buffer - po->tmpspace));
-
- return 0;
-}
-
-
-/*
- * Output a large number of bits.
- */
-int
-asn_put_many_bits(asn_bit_outp_t *po, const uint8_t *src, int nbits) {
-
- while(nbits) {
- uint32_t value;
-
- if(nbits >= 24) {
- value = (src[0] << 16) | (src[1] << 8) | src[2];
- src += 3;
- nbits -= 24;
- if(asn_put_few_bits(po, value, 24))
- return -1;
- } else {
- value = src[0];
- if(nbits > 8)
- value = (value << 8) | src[1];
- if(nbits > 16)
- value = (value << 8) | src[2];
- if(nbits & 0x07)
- value >>= (8 - (nbits & 0x07));
- if(asn_put_few_bits(po, value, nbits))
- return -1;
- break;
- }
- }
-
- return 0;
-}
-
-
-int
-asn_put_aligned_flush(asn_bit_outp_t *po) {
- uint32_t unused_bits = (0x7 & (8 - (po->nboff & 0x07)));
- size_t complete_bytes =
- (po->buffer ? po->buffer - po->tmpspace : 0) + ((po->nboff + 7) >> 3);
-
- if(unused_bits) {
- po->buffer[po->nboff >> 3] &= ~0u << unused_bits;
- }
-
- if(po->output(po->tmpspace, complete_bytes, po->op_key) < 0) {
- return -1;
- } else {
- po->buffer = po->tmpspace;
- po->nboff = 0;
- po->nbits = 8 * sizeof(po->tmpspace);
- po->flushed_bytes += complete_bytes;
- return 0;
- }
-}
-