From: Max msuraev@sysmocom.de

Add bit map encoder and decoder functions: decoder is fully functional while encoder is good enough for testing - no backtracking to find the best possible compression is implemented. If somebody is willing to implement MS side of EDGE than this has to be expanded. Add corresponding tests. N. B: the encoding is implemented according to ETSI TS 44.060 which is slightly different from T4 used for fax according to CCITT G31D (RFC 804).

Ticket: OW#2407 Sponsored-by: On-Waves ehf --- .gitignore | 1 + include/Makefile.am | 1 + include/osmocom/core/bitcomp.h | 42 ++++ src/Makefile.am | 2 +- src/bitcomp.c | 477 +++++++++++++++++++++++++++++++++++++++++ tests/Makefile.am | 7 +- tests/bits/bitcomp_test.c | 66 ++++++ tests/bits/bitcomp_test.ok | 29 +++ tests/testsuite.at | 6 + 9 files changed, 628 insertions(+), 3 deletions(-) create mode 100644 include/osmocom/core/bitcomp.h create mode 100644 src/bitcomp.c create mode 100644 tests/bits/bitcomp_test.c create mode 100644 tests/bits/bitcomp_test.ok

diff --git a/.gitignore b/.gitignore index 955634e..8904938 100644 --- a/.gitignore +++ b/.gitignore @@ -82,6 +82,7 @@ tests/vty/vty_test tests/gb/gprs_bssgp_test tests/smscb/gsm0341_test tests/bitvec/bitvec_test +tests/bits/bitcomp_test tests/gprs/gprs_test tests/msgb/msgb_test

diff --git a/include/Makefile.am b/include/Makefile.am index 07d6c00..a965fb9 100644 --- a/include/Makefile.am +++ b/include/Makefile.am @@ -7,6 +7,7 @@ nobase_include_HEADERS = \ osmocom/core/bit64gen.h \ osmocom/core/bits.h \ osmocom/core/bitvec.h \ + osmocom/core/bitcomp.h \ osmocom/core/conv.h \ osmocom/core/crc16.h \ osmocom/core/crc16gen.h \ diff --git a/include/osmocom/core/bitcomp.h b/include/osmocom/core/bitcomp.h new file mode 100644 index 0000000..89eccbc --- /dev/null +++ b/include/osmocom/core/bitcomp.h @@ -0,0 +1,42 @@ +#pragma once + +/* bit compression routines */ + +/* (C) 2016 sysmocom s.f.m.c. GmbH by Max Suraev msuraev@sysmocom.de + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +/*! \defgroup bitcomp Bit compression + * @{ + */ + +/*! \file bitcomp.h + * \brief Osmocom bit compression routines + */ + +#include <stdint.h> +#include <stdbool.h> + +#include <osmocom/core/bitvec.h> + + +int osmo_t4_encode(struct bitvec *bv); +int osmo_t4_decode(const struct bitvec *in, bool cc, struct bitvec *out); + +/*! @} */ diff --git a/src/Makefile.am b/src/Makefile.am index c46cddf..45a77e3 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -9,7 +9,7 @@ lib_LTLIBRARIES = libosmocore.la

libosmocore_la_LIBADD = $(BACKTRACE_LIB) $(TALLOC_LIBS) libosmocore_la_SOURCES = timer.c select.c signal.c msgb.c bits.c \ - bitvec.c statistics.c \ + bitvec.c bitcomp.c statistics.c \ write_queue.c utils.c socket.c \ logging.c logging_syslog.c rate_ctr.c \ gsmtap_util.c crc16.c panic.c backtrace.c \ diff --git a/src/bitcomp.c b/src/bitcomp.c new file mode 100644 index 0000000..b0aa6de --- /dev/null +++ b/src/bitcomp.c @@ -0,0 +1,477 @@ +/* bit compression routines */ + +/* (C) 2016 sysmocom s.f.m.c. GmbH by Max Suraev msuraev@sysmocom.de + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +/*! \defgroup bitcomp Bit compression + * @{ + */ + +/*! \file bitcomp.c + * \brief Osmocom bit compression routines + */ + +#include <stdint.h> +#include <stdbool.h> +#include <errno.h> +#include <string.h> + +#include <osmocom/core/bitvec.h> +#include <osmocom/core/bitcomp.h> + +/* + * Terminating codes for uninterrupted sequences of 0 and 1 up to 64 bit length + * according to TS 44.060 9.1.10 + */ +unsigned _term[2][64] = { + { + 0b0000110111, + 0b10, + 0b11, + 0b010, + 0b011, + 0b0011, + 0b0010, + 0b00011, + 0b000101, + 0b000100, + 0b0000100, + 0b0000101, + 0b0000111, + 0b00000100, + 0b00000111, + 0b000011000, + 0b0000010111, + 0b0000011000, + 0b0000001000, + 0b00001100111, + 0b00001101000, + 0b00001101100, + 0b00000110111, + 0b00000101000, + 0b00000010111, + 0b00000011000, + 0b000011001010, + 0b000011001011, + 0b000011001100, + 0b000011001101, + 0b000001101000, + 0b000001101001, + 0b000001101010, + 0b000001101011, + 0b000011010010, + 0b000011010011, + 0b000011010100, + 0b000011010101, + 0b000011010110, + 0b000011010111, + 0b000001101100, + 0b000001101101, + 0b000011011010, + 0b000011011011, + 0b000001010100, + 0b000001010101, + 0b000001010110, + 0b000001010111, + 0b000001100100, + 0b000001100101, + 0b000001010010, + 0b000001010011, + 0b000000100100, + 0b000000110111, + 0b000000111000, + 0b000000100111, + 0b000000101000, + 0b000001011000, + 0b000001011001, + 0b000000101011, + 0b000000101100, + 0b000001011010, + 0b000001100110, + 0b000001100111 + }, + { + 0b00110101, + 0b000111, + 0b0111, + 0b1000, + 0b1011, + 0b1100, + 0b1110, + 0b1111, + 0b10011, + 0b10100, + 0b00111, + 0b01000, + 0b001000, + 0b000011, + 0b110100, + 0b110101, + 0b101010, + 0b101011, + 0b0100111, + 0b0001100, + 0b0001000, + 0b0010111, + 0b0000011, + 0b0000100, + 0b0101000, + 0b0101011, + 0b0010011, + 0b0100100, + 0b0011000, + 0b00000010, + 0b00000011, + 0b00011010, + 0b00011011, + 0b00010010, + 0b00010011, + 0b00010100, + 0b00010101, + 0b00010110, + 0b00010111, + 0b00101000, + 0b00101001, + 0b00101010, + 0b00101011, + 0b00101100, + 0b00101101, + 0b00000100, + 0b00000101, + 0b00001010, + 0b00001011, + 0b01010010, + 0b01010011, + 0b01010100, + 0b01010101, + 0b00100100, + 0b00100101, + 0b01011000, + 0b01011001, + 0b01011010, + 0b01011011, + 0b01001010, + 0b01001011, + 0b00110010, + 0b00110011, + 0b00110100 + } +}; + +unsigned _term_length[2][64] = { + {10, 2, 2, 3, 3, 4, 4, 5, 6, 6, 7, 7, 7, 8, 8, 9, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12}, + {8, 6, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8} +}; + +unsigned _min_term_length[] = {2, 4}; +unsigned _min_make_up_length[] = {10, 5}; + +unsigned _max_term_length[] = {12, 8}; +unsigned _max_make_up_length[] = {13, 9}; + +unsigned _make_up_length[2][15] = { + {10, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13}, + {5, 5, 6, 7, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9} +}; + +unsigned _make_up_ind[15] = {64, 128, 192, 256, 320, 384, 448, 512, 576, 640, 704, 768, 832, 896, 960}; + +unsigned _make_up[2][15] = { + { + 0b0000001111, + 0b000011001000, + 0b000011001001, + 0b000001011011, + 0b000000110011, + 0b000000110100, + 0b000000110101, + 0b0000001101100, + 0b0000001101101, + 0b0000001001010, + 0b0000001001011, + 0b0000001001100, + 0b0000001001101, + 0b0000001110010, + 0b0000001110011 + }, + { + 0b11011, + 0b10010, + 0b010111, + 0b0110111, + 0b00110110, + 0b00110111, + 0b01100100, + 0b01100101, + 0b01101000, + 0b01100111, + 0b011001100, + 0b011001101, + 0b011010010, + 0b011010011, + 0b011010100 + } +}; + +/*! \brief Attempt to decode compressed bit vector + * + * Return length of RLE according to modified ITU-T T.4 from TS 44.060 Table 9.1.10.2 + * or -1 if no applicable RLE found + * N. B: we need explicit bit length to make decoding unambiguous +*/ +static inline int _rle_term(unsigned w, bool b, unsigned bits) +{ + unsigned i; + for (i = 0; i < 64; i++) + if (w == _term[b][i] && bits == _term_length[b][i]) + return i; + return -1; +} + +static inline int _rle_makeup(unsigned w, bool b, unsigned bits) +{ + unsigned i; + for (i = 0; i < 15; i++) + if (w == _make_up[b][i] && bits == _make_up_length[b][i]) + return _make_up_ind[i]; + return -1; +} + +/*! \brief Make-up codes for a given length + * + * Return proper make-up code word for an uninterrupted sequence of b bits + * of length len according to modified ITU-T T.4 from TS 44.060 Table 9.1.10.2 */ +static inline int _rle(struct bitvec *bv, unsigned len, bool b) +{ + if (len >= 960) { + bitvec_set_uint(bv, _make_up[b][14], _make_up_length[b][14]); + return bitvec_set_uint(bv, _term[b][len - 960], _term_length[b][len - 960]); + } + + if (len >= 896) { + bitvec_set_uint(bv, _make_up[b][13], _make_up_length[b][13]); + return bitvec_set_uint(bv, _term[b][len - 896], _term_length[b][len - 896]); + } + + if (len >= 832) { + bitvec_set_uint(bv, _make_up[b][12], _make_up_length[b][12]); + return bitvec_set_uint(bv, _term[b][len - 832], _term_length[b][len - 832]); + } + + if (len >= 768) { + bitvec_set_uint(bv, _make_up[b][11], _make_up_length[b][11]); + return bitvec_set_uint(bv, _term[b][len - 768], _term_length[b][len - 768]); + } + + if (len >= 704) { + bitvec_set_uint(bv, _make_up[b][10], _make_up_length[b][10]); + return bitvec_set_uint(bv, _term[b][len - 704], _term_length[b][len - 704]); + } + + if (len >= 640) { + bitvec_set_uint(bv, _make_up[b][9], _make_up_length[b][9]); + return bitvec_set_uint(bv, _term[b][len - 640], _term_length[b][len - 640]); + } + + if (len >= 576) { + bitvec_set_uint(bv, _make_up[b][8], _make_up_length[b][8]); + return bitvec_set_uint(bv, _term[b][len - 576], _term_length[b][len - 576]); + } + + if (len >= 512) { + bitvec_set_uint(bv, _make_up[b][7], _make_up_length[b][7]); + return bitvec_set_uint(bv, _term[b][len - 512], _term_length[b][len - 512]); + } + + if (len >= 448) { + bitvec_set_uint(bv, _make_up[b][6], _make_up_length[b][6]); + return bitvec_set_uint(bv, _term[b][len - 448], _term_length[b][len - 448]); + } + + if (len >= 384) { + bitvec_set_uint(bv, _make_up[b][5], _make_up_length[b][5]); + return bitvec_set_uint(bv, _term[b][len - 384], _term_length[b][len - 384]); + } + + if (len >= 320) { + bitvec_set_uint(bv, _make_up[b][4], _make_up_length[b][4]); + return bitvec_set_uint(bv, _term[b][len - 320], _term_length[b][len - 320]); + } + + if (len >= 256) { + bitvec_set_uint(bv, _make_up[b][3], _make_up_length[b][3]); + return bitvec_set_uint(bv, _term[b][len - 256], _term_length[b][len - 256]); + } + + if (len >= 192) { + bitvec_set_uint(bv, _make_up[b][2], _make_up_length[b][2]); + return bitvec_set_uint(bv, _term[b][len - 192], _term_length[b][len - 192]); + } + + if (len >= 128) { + bitvec_set_uint(bv, _make_up[b][1], _make_up_length[b][1]); + return bitvec_set_uint(bv, _term[b][len - 128], _term_length[b][len - 128]); + } + + if (len >= 64) { + bitvec_set_uint(bv, _make_up[b][0], _make_up_length[b][0]); + return bitvec_set_uint(bv, _term[b][len - 64], _term_length[b][len - 64]); + } + + return bitvec_set_uint(bv, _term[b][len], _term_length[b][len]); +} + +enum dec_state { + EXPECT_TERM, // only TERM is expected, keep parsing with the same color code + TOO_LONG, // that's what she said + NEED_MORE_BITS, // parsing failed, retry with bigger code word + CORRUPT, // kaboom! how the hell did you made that happen?! + OK // move along, nothing to see here +}; + +static inline enum dec_state _t4_step(struct bitvec *v, uint16_t w, bool b, unsigned bits, bool term_only) +{ + if (bits > _max_make_up_length[b]) + return TOO_LONG; + if (bits < _min_term_length[b]) + return NEED_MORE_BITS; + + if (term_only) { + if (bits > _max_term_length[b]) + return CORRUPT; + int t = _rle_term(w, b, bits); + if (-1 != t) { + bitvec_fill(v, t, b ? ONE : ZERO); + return OK; + } + return NEED_MORE_BITS; + } + + int m = _rle_makeup(w, b, bits); + if (-1 != m) { + bitvec_fill(v, m, b ? ONE : ZERO); + return EXPECT_TERM; + } + + m = _rle_term(w, b, bits); + if (-1 != m) { + bitvec_fill(v, m, b ? ONE : ZERO); + return OK; + } + + return NEED_MORE_BITS; +} + +/*! \brief decode T4-encoded bit vector + * Assumes MSB first encoding. + * \param[in] in bit vector with encoded data + * \param[in] cc color code (whether decoding should start with 1 or 0) + * \param[out] out the bit vector to store result into + * returns 0 on success, negative value otherwise + */ +int osmo_t4_decode(const struct bitvec *in, bool cc, struct bitvec *out) +{ + uint8_t orig[in->data_len]; + struct bitvec vec; + vec.data = orig; + vec.data_len = in->data_len; + bitvec_zero(&vec); + memcpy(vec.data, in->data, in->data_len); + vec.cur_bit = in->cur_bit; + + // init decoder: + unsigned bits = _min_term_length[cc]; + enum dec_state d; + int16_t w = bitvec_get_int16_msb(&vec, bits); + bool b = cc; + bool term_only = false; + + while (vec.cur_bit > 0) { + d = _t4_step(out, w, b, bits, term_only); + + switch (d) { + case EXPECT_TERM: + bitvec_shiftl(&vec, bits); + bits = _min_term_length[b]; + w = bitvec_get_int16_msb(&vec, bits); + term_only = true; + break; + case OK: + bitvec_shiftl(&vec, bits); + bits = _min_term_length[!b]; + w = bitvec_get_int16_msb(&vec, bits); + b = !b; + term_only = false; + break; + case NEED_MORE_BITS: + bits++; + w = bitvec_get_int16_msb(&vec, bits); + break; + case TOO_LONG: + return -EINVAL; + case CORRUPT: + return -EINVAL; + } + } + + return 0; +} + +/*! \brief encode bit vector in-place using T4 encoding + * Assumes MSB first encoding. + * \param[in] bv bit vector to be encoded + * returns color code (if the encoding started with 0 or 1) or -1 on failure (encoded is bigger than original) + */ +int osmo_t4_encode(struct bitvec *bv) +{ + unsigned rl0 = bitvec_rl(bv, false), rl1 = bitvec_rl(bv, true); + int r = (rl0 > rl1) ? 0 : 1; + uint8_t orig[bv->data_len], tmp[bv->data_len * 2]; // FIXME: better estimate max possible encoding overhead + struct bitvec comp, vec; + comp.data = tmp; + comp.data_len = bv->data_len * 2; + bitvec_zero(&comp); + vec.data = orig; + vec.data_len = bv->data_len; + bitvec_zero(&vec); + memcpy(vec.data, bv->data, bv->data_len); + vec.cur_bit = bv->cur_bit; + + while (vec.cur_bit > 0) { + if (rl0 > rl1) { + bitvec_shiftl(&vec, rl0); + _rle(&comp, rl0, false); + } else { + bitvec_shiftl(&vec, rl1); + _rle(&comp, rl1, true); + } +// printf(" -> [%d/%d]", comp.cur_bit + vec.cur_bit, bv->cur_bit); // TODO: implement backtracking + rl0 = bitvec_rl(&vec, false); + rl1 = bitvec_rl(&vec, true); + } + if (comp.cur_bit < bv->cur_bit) { + memcpy(bv->data, tmp, bv->data_len); + bv->cur_bit = comp.cur_bit; + return r; + } + return -1; +} + + diff --git a/tests/Makefile.am b/tests/Makefile.am index a4a6b2e..571e87b 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -12,7 +12,7 @@ check_PROGRAMS = timer/timer_test sms/sms_test ussd/ussd_test \ loggingrb/loggingrb_test strrb/strrb_test \ vty/vty_test comp128/comp128_test utils/utils_test \ smscb/gsm0341_test stats/stats_test \ - bitvec/bitvec_test msgb/msgb_test + bitvec/bitvec_test msgb/msgb_test bits/bitcomp_test

if ENABLE_MSGFILE check_PROGRAMS += msgfile/msgfile_test @@ -42,6 +42,9 @@ bits_bitrev_test_LDADD = $(top_builddir)/src/libosmocore.la bitvec_bitvec_test_SOURCES = bitvec/bitvec_test.c bitvec_bitvec_test_LDADD = $(top_builddir)/src/libosmocore.la

+bits_bitcomp_test_SOURCES = bits/bitcomp_test.c +bits_bitcomp_test_LDADD = $(top_builddir)/src/libosmocore.la + conv_conv_test_SOURCES = conv/conv_test.c conv_conv_test_LDADD = $(top_builddir)/src/libosmocore.la

@@ -136,7 +139,7 @@ EXTRA_DIST = testsuite.at $(srcdir)/package.m4 $(TESTSUITE) \ loggingrb/logging_test.err strrb/strrb_test.ok \ vty/vty_test.ok comp128/comp128_test.ok \ utils/utils_test.ok stats/stats_test.ok \ - bitvec/bitvec_test.ok msgb/msgb_test.ok + bitvec/bitvec_test.ok msgb/msgb_test.ok bits/bitcomp_test.ok

DISTCLEANFILES = atconfig

diff --git a/tests/bits/bitcomp_test.c b/tests/bits/bitcomp_test.c new file mode 100644 index 0000000..f6895cf --- /dev/null +++ b/tests/bits/bitcomp_test.c @@ -0,0 +1,66 @@ +#include <inttypes.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> +#include <time.h> +#include <stdbool.h> +#include <errno.h> + +#include <osmocom/core/utils.h> +#include <osmocom/core/bits.h> +#include <osmocom/core/bitcomp.h> + +static char lol[1024]; // for pretty-printing + +int main(int argc, char **argv) +{ + srand(time(NULL)); + + struct bitvec bv, out; + uint8_t i = 20, test[i], data[i]; + + bv.data_len = i; + bv.data = test; + out.data_len = i; + out.data = data; + bitvec_zero(&bv); + bitvec_zero(&out); + + printf("\nrunning static tests...\n"); + + printf("\nTEST1:\n 00110111 01000111 10000001 1111\n"); + bitvec_zero(&bv); + bitvec_set_uint(&bv, 0x374781F, 28); bitvec_to_string_r(&bv, lol); printf("%s", lol); + + printf("\nEncoded:\n%d", osmo_t4_encode(&bv)); bitvec_to_string_r(&bv, lol); printf("%s", lol); + printf(" [%d]\nExpected:\n0 11011110 10001000 01110101 01100101 100 [35]\n", bv.cur_bit); + + bitvec_zero(&bv); + bitvec_set_uint(&bv, 0xDE887565, 32); + bitvec_set_uint(&bv, 4, 3); + bitvec_to_string_r(&bv, lol); + printf(" %s [%d]\n", lol, bv.cur_bit); + int d = osmo_t4_decode(&bv, 0, &out); + printf("\nDecoded:\n%d", d); + bitvec_to_string_r(&out, lol); + printf("%s [%d]\n", lol, out.cur_bit); + printf("Expected:\n 00110111 01000111 10000001 1111 \n"); + + printf("\nTEST2:\n 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00\n"); + bitvec_zero(&bv); + bitvec_set_uint(&bv, 0xFFFFFFFF, 32); + bitvec_set_uint(&bv, 0xFFFFFFFF, 32); + bitvec_set_uint(&bv, 0xFFFFFC00, 26); bitvec_to_string_r(&bv, lol); printf("%s", lol); + printf("\nEncoded:\n%d", osmo_t4_encode(&bv)); bitvec_to_string_r(&bv, lol); printf("%s", lol); + printf(" [%d]\nExpected:\n1 11011101 01000001 00 [18]\n", bv.cur_bit); + + bitvec_zero(&out); + d = osmo_t4_decode(&bv, 1, &out); + printf("\nDecoded:\n%d", d); + bitvec_to_string_r(&out, lol); + printf("%s [%d]\n", lol, out.cur_bit); + printf("Expected:\n 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00\n"); + + return 0; +} diff --git a/tests/bits/bitcomp_test.ok b/tests/bits/bitcomp_test.ok new file mode 100644 index 0000000..238f3c4 --- /dev/null +++ b/tests/bits/bitcomp_test.ok @@ -0,0 +1,29 @@ + +running static tests... + +TEST1: + 00110111 01000111 10000001 1111 + 00110111 01000111 10000001 1111 +Encoded: +-1 00110111 01000111 10000001 1111 [28] +Expected: +0 11011110 10001000 01110101 01100101 100 [35] + 11011110 10001000 01110101 01100101 100 [35] + +Decoded: +0 00110111 01000111 10000001 1111 [28] +Expected: + 00110111 01000111 10000001 1111 + +TEST2: + 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00 + 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00 +Encoded: +1 11011101 01000001 00 [18] +Expected: +1 11011101 01000001 00 [18] + +Decoded: +0 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00 [90] +Expected: + 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000 00 diff --git a/tests/testsuite.at b/tests/testsuite.at index 9cda1de..3d4d526 100644 --- a/tests/testsuite.at +++ b/tests/testsuite.at @@ -27,6 +27,12 @@ cat $abs_srcdir/bitvec/bitvec_test.ok > expout AT_CHECK([$abs_top_builddir/tests/bitvec/bitvec_test], [0], [expout], [ignore]) AT_CLEANUP

+AT_SETUP([bitcomp]) +AT_KEYWORDS([bitcomp]) +cat $abs_srcdir/bits/bitcomp_test.ok > expout +AT_CHECK([$abs_top_builddir/tests/bits/bitcomp_test], [0], [expout]) +AT_CLEANUP + AT_SETUP([conv]) AT_KEYWORDS([conv]) cat $abs_srcdir/conv/conv_test.ok > expout

On 02 Feb 2016, at 12:19, suraev@alumni.ntnu.no wrote:

Dear Max,

• memcpy(tmp, bv->data, 2);
• return osmo_load16be(tmp) >> (16 - num_bits);

load16be is working byte by byte as well so what do we win by this load?

+/*! \brief fill num_bits with \fill starting from the current position

• • returns 0 on success, negative otherwise (out of vector boundary)
• */

+int bitvec_fill(struct bitvec *bv, unsigned int num_bits, enum bit_value fill) +{

• unsigned i, stop = bv->cur_bit + num_bits;
• for (i = bv->cur_bit; i < stop; i++)

• if (bitvec_set_bit(bv, fill) < 0)
  

• 	return -EINVAL;
  

• return 0;

+}

/*! \brief pad all remaining bits up to num_bits */ int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit) {

• unsigned int i;
• for (i = bv->cur_bit; i <= up_to_bit; i++)

• bitvec_set_bit(bv, L);
  

• int n = up_to_bit - bv->cur_bit + 1;
• if (n < 1)

• return 0;
  

so we are going from unsigned to int and then 'n' is "converted" to unsigned int as well. Is this what we want?

+/*! \brief convert enum to corresponding character */ +char bit_value_to_char(enum bit_value v) +{

• switch (v) {
• case ZERO: return '0';
• case ONE: return '1';
• case L: return 'L';
• case H: return 'H';
• }
• /* make compiler happy - "avoid control reaches end of non-void function" warning: */

seeing is believing? Which gcc? I had proposed to use __builtin_unreachable here. If we know we don't end up there, put this into the "branch" and the warning is gone. Or abort() or __builtin_trap.

• return '?';

+}

+/*! \brief prints bit vector to provided string

• • It's caller's responcibility to ensure that we won't shoot him in the foot.

typo, how long is "str"? So either pass a size or write it in the comment of how long it needs to be depending on cur_bit? And what does the _r stand for? Is it similiar to the libc _r functions where an external buffer/pointer is provided?

+/* we assume that x have at least 1 non-b bit */ +static inline unsigned _leading_bits(uint8_t x, bool b)

_ and __ are reserved for the system, let us not use it. By having this method as static we already don't pollute the global namespace.

+/*! \brief Return number (bits) of uninterrupted run of \b in \bv starting from the MSB */

Are you sure that \b and \bv refer to the params? not like \param b, \param bv? Did you look at the documentation generated by doxygen?

• fprintf(stderr, "out: %s\n", osmo_hexdump(out, sizeof(out)));
  

• printf("out: %s\n", osmo_hexdump(out, sizeof(out)));
  

why? more output to be tracked? we could not ignore stderr if we want to?

OSMO_ASSERT(out[0] == 0xff);
OSMO_ASSERT(out[in_size+1] == 0xff);

@@ -72,11 +145,77 @@ static void test_unhex(const char *hex)

int main(int argc, char **argv) {

• srand(time(NULL));

why?