Bitpacking

Collaboration diagram for Bitpacking:

Functions
	DoxyDefine (void switch_bitpack_init(switch_bitpack_t *pack, int32_t bitlen, switch_byte_t *buf, uint32_t buflen, switch_bitpack_mode_t mode)) static inline int8_t switch_bitpack_init(switch_bitpack_t *pack
	Initialize a bitpack object. More...
	memset (buf, 0, buflen)
static void	pack_check_over (switch_bitpack_t *pack)
	DoxyDefine (int8_t switch_bitpack_done(switch_bitpack_t *pack)) static inline int8_t switch_bitpack_done(switch_bitpack_t *pack)
	finalize a bitpack object More...
	DoxyDefine (int8_t switch_bitpack_out(switch_bitpack_t *unpack, switch_byte_t in)) static inline int8_t switch_bitpack_out(switch_bitpack_t *unpack
	pull data out of a bitpack object into it's buffer More...
	if ((uint32_t)(unpack->cur-unpack->buf) > unpack->buflen)
	pack_check_over (unpack)
	while (unpack->bits_cur<=SWITCH_BITS_PER_BYTE)
	DoxyDefine (int8_t switch_bitpack_in(switch_bitpack_t *pack, switch_byte_t in)) static inline int8_t switch_bitpack_in(switch_bitpack_t *pack
	pack data into a bitpack object's buffer More...
	if ((uint32_t)(pack->cur-pack->buf) > pack->buflen)
	if (next > SWITCH_BITS_PER_BYTE)

Variables
static const uint8_t	SWITCH_BITPACKED_MASKS [] = { 0, 1, 3, 7, 15, 31, 63, 127, 255 }
static const uint8_t	SWITCH_REVERSE_BITPACKED_MASKS [] = { 255, 254, 252, 248, 240, 224, 192, 128 }
switch_byte_t	bitlen
switch_byte_t switch_byte_t *	buf = buf
switch_byte_t switch_byte_t uint32_t	buflen = buflen
switch_byte_t switch_byte_t uint32_t switch_bitpack_mode_t	mode
pack	frame_bits = bitlen
pack	cur = pack->buf
	return
switch_byte_t	in
unpack	bits_cur = 0
unpack	this_byte = this_byte = in
pack	bits_tot = pack->frame_bits
	else

Detailed Description

Function Documentation

DoxyDefine

(

void

switch_bitpack_initswitch_bitpack_t *pack, int32_t bitlen, switch_byte_t *buf, uint32_t buflen, switch_bitpack_mode_t mode

)

Initialize a bitpack object.

Parameters

pack	the pack object
bitlen	the number of bits per packet
buf	the buffer to use for storage
buflen	the length of the storage buffer
mode	RFC3551 or AAL2 mode (curse you backwards folks)

DoxyDefine

(

int8_t

switch_bitpack_doneswitch_bitpack_t *pack

)

finalize a bitpack object

Parameters

pack	the pack/unpack object

Definition at line 128 of file switch_bitpack.h.

References switch_bitpack_t::bits_cur, switch_bitpack_t::bytes, switch_bitpack_t::cur, switch_bitpack_t::mode, switch_bitpack_t::over, pack_check_over(), SWITCH_BITPACK_MODE_AAL2, and SWITCH_BITS_PER_BYTE.

{

        if (pack->bits_cur && pack->bits_cur < SWITCH_BITS_PER_BYTE) {
                pack->bytes++;
                if (pack->mode == SWITCH_BITPACK_MODE_AAL2) {
                        *pack->cur <<= SWITCH_BITS_PER_BYTE - pack->bits_cur;
                }
        }

        if (pack->over) {
                pack_check_over(pack);
        }
        return 0;
}

DoxyDefine

(

int8_t

switch_bitpack_outswitch_bitpack_t *unpack, switch_byte_t in

)

pull data out of a bitpack object into it's buffer

Parameters

unpack	the pack/unpack object
in	a 1 byte int packed with bits

Returns

-1 if the buffer is full otherwise 0

DoxyDefine

(

int8_t

switch_bitpack_inswitch_bitpack_t *pack, switch_byte_t in

)

pack data into a bitpack object's buffer

Parameters

pack	the pack/unpack object
in	a 1 byte int with 1 packet worth of bits

Returns

-1 if the buffer is full otherwise 0

if	(	(uint32_t)(unpack->cur-unpack->buf)	,
		unpack->	buflen
	)

Definition at line 157 of file switch_bitpack.h.

Referenced by check_ice(), cJSON_Duplicate(), early_thread_run(), parse_presence_data_cols(), process_rtcp_report(), read_rtcp_packet(), record_callback(), rtp_common_read(), switch_channel_get_cap_string(), switch_channel_get_flag_string(), switch_console_sort_matches(), switch_core_media_absorb_sdp(), switch_core_media_negotiate_sdp(), switch_core_media_process_udptl(), switch_core_media_receive_message(), switch_core_session_read_frame(), switch_core_session_write_frame(), switch_ivr_process_fh(), switch_ivr_record_file(), SWITCH_STANDARD_SCHED_FUNC(), switch_stun_packet_attribute_get_xor_mapped_address(), switch_stun_packet_parse(), switch_xml_attr(), switch_xml_config_parse_event(), switch_xml_pi(), timer_init(), tzparse(), and vxprintf().

                                                                     {
                return -1;
        }

if	(	(uint32_t)(pack->cur-pack->buf)	,
		pack->	buflen
	)

Definition at line 228 of file switch_bitpack.h.

                                                               {
                return -1;
        }

if	(	next	,
		SWITCH_BITS_PER_BYTE
	)

Definition at line 234 of file switch_bitpack.h.

References switch_bitpack_t::bits_cur, switch_bitpack_t::bytes, switch_bitpack_t::cur, switch_bitpack_t::frame_bits, switch_bitpack_t::mode, switch_bitpack_t::shiftby, SWITCH_BITPACK_MODE_RFC3551, and SWITCH_BITS_PER_BYTE.

                                         {
                switch_byte_t a = 0, b = 0, rem, nxt;
                rem = SWITCH_BITS_PER_BYTE - pack->bits_cur;
                nxt = pack->frame_bits - rem;
                if (pack->mode == SWITCH_BITPACK_MODE_RFC3551) {
                        a = in & SWITCH_BITPACKED_MASKS[rem];
                        b = in >> rem;
                        a <<= pack->shiftby;
                        *pack->cur |= a;
                        pack->cur++;
                        *pack->cur |= b;
                        pack->bits_cur = pack->shiftby = nxt;
                } else {
                        a = in >> nxt;
                        b = in & SWITCH_BITPACKED_MASKS[nxt];
                        *pack->cur <<= rem;
                        *pack->cur |= a;
                        pack->cur++;
                        *pack->cur |= b;
                        pack->bits_cur = nxt;

                }
                pack->bytes++;

        } else {

memset	(	buf	,
		0	,
		buflen
	)

Referenced by add_xml_header(), cJSON_New_Item(), clear_ice(), collect_thread_run(), db_pick_path(), do_2833(), early_thread_run(), fetch_device_stats(), SimpleGlobBase< SOCHAR >::FindDone(), generate_m(), CoreSession::getDigits(), handle_ice(), hashtable_expand(), inband_dtmf_generate_callback(), init_upnp(), main(), meta_on_dtmf(), new_header(), play_and_collect(), CoreSession::playAndGetDigits(), preprocess(), print_array(), print_object(), process_rtcp_report(), read_displace_callback(), read_rtp_packet(), CoreSession::recordFile(), reincarnate_protect(), rtp_common_read(), session_audio_callback(), setup_ringback(), SimpleGlobBase< SOCHAR >::SimpleGlobBase(), CoreSession::streamFile(), switch_ast2regex(), switch_buffer_create_dynamic(), switch_cache_db_execute_sql2str(), switch_cache_db_status(), switch_caller_profile_new(), switch_change_sln_volume_granular(), switch_channel_dequeue_dtmf_string(), switch_channel_expand_variables_check(), switch_channel_global_init(), switch_channel_set_timestamps(), switch_config_close_file(), switch_config_open_file(), switch_console_loop(), switch_core_codec_add_video_implementation(), switch_core_codec_decode(), switch_core_codec_destroy(), switch_core_codec_init_with_bitrate(), switch_core_codec_parse_fmtp(), switch_core_db_column_text(), switch_core_gen_encoded_silence(), switch_core_get_stacksizes(), switch_core_init(), switch_core_measure_time(), switch_core_media_activate_rtp(), switch_core_media_bug_read(), switch_core_media_gen_local_sdp(), switch_core_media_negotiate_sdp(), switch_core_media_read_frame(), switch_core_memory_init(), switch_core_perform_alloc(), switch_core_perform_permanent_alloc(), switch_core_perform_session_alloc(), switch_core_session_clear_crypto(), switch_core_session_get_read_impl(), switch_core_session_get_video_read_impl(), switch_core_session_get_video_write_impl(), switch_core_session_get_write_impl(), switch_core_session_init(), switch_core_session_queue_indication(), switch_core_session_raw_read(), switch_core_session_read_frame(), switch_core_session_set_codec_slin(), switch_core_session_set_read_codec(), switch_core_session_set_real_read_codec(), switch_core_session_set_video_read_codec(), switch_core_session_write_frame(), switch_core_setrlimits(), switch_core_timer_destroy(), switch_core_timer_init(), switch_create_hashtable(), switch_dir_open(), switch_event_add_array(), switch_event_create_subclass_detailed(), switch_event_del_header_val(), switch_event_expand_headers_check(), switch_fd_read_dline(), switch_find_local_ip(), switch_fp_read_dline(), switch_fulldate_cmp(), switch_g711a_decode(), switch_g711u_decode(), switch_generate_sln_silence(), switch_get_addr(), switch_img_fill(), switch_img_write_text_img(), switch_ivr_digit_stream_new(), switch_ivr_digit_stream_parser_new(), switch_ivr_dmachine_clear(), switch_ivr_gentones(), switch_ivr_menu_execute(), switch_ivr_originate(), switch_ivr_park(), switch_ivr_phrase_macro_event(), switch_ivr_play_file(), switch_ivr_read(), switch_ivr_record_file(), switch_ivr_set_json_chan_vars(), switch_ivr_set_xml_chan_var(), switch_ivr_speak_text(), switch_ivr_speak_text_handle(), switch_ivr_tone_detect_session(), switch_ivr_unbind_dtmf_meta_session(), switch_ivr_wait_for_answer(), switch_load_core_config(), switch_load_network_lists(), switch_load_timezones(), switch_loadable_module_init(), switch_log_vprintf(), SWITCH_MODULE_LOAD_FUNCTION(), switch_nat_init(), switch_nat_multicast_runtime(), switch_odbc_handle_callback_exec_detailed(), switch_odbc_handle_new(), switch_pgsql_cancel_real(), switch_pgsql_handle_new(), switch_pgsql_next_result_timed(), switch_play_and_get_digits(), switch_rtp_add_crypto_key(), switch_rtp_change_interval(), switch_rtp_create(), switch_rtp_enable_vad(), switch_rtp_reset(), switch_rtp_udptl_mode(), switch_say_file_handle_create(), switch_separate_string(), switch_sockaddr_create(), switch_socket_create_pollfd(), switch_speex_init(), switch_system_fork(), switch_xml_add_child(), switch_xml_new(), switch_xml_toxml_buf(), system_thread(), teletone_init_session(), teletone_mux_tones(), teletone_run(), tm2switchtime(), tztime(), and write_displace_callback().

static void pack_check_over ( switch_bitpack_t *  pack )

inlinestatic

Definition at line 94 of file switch_bitpack.h.

References switch_bitpack_t::bits_cur, switch_bitpack_t::bytes, switch_bitpack_t::cur, switch_bitpack_t::mode, switch_bitpack_t::over, switch_assert, SWITCH_BITPACK_MODE_RFC3551, SWITCH_BITS_PER_BYTE, this_byte, switch_bitpack_t::this_byte, and switch_bitpack_t::under.

Referenced by DoxyDefine().

{
        switch_byte_t this_byte = pack->this_byte;

        if (pack->over) {
                pack->bits_cur = pack->over;

                if (pack->mode == SWITCH_BITPACK_MODE_RFC3551) {
                        switch_assert(pack->over <= 8);
                        this_byte &= SWITCH_BITPACKED_MASKS[pack->over];
                        this_byte <<= pack->under;
                        *pack->cur |= this_byte;
                        pack->cur++;
                } else {
                        switch_byte_t mask = SWITCH_BITS_PER_BYTE - pack->over;
                        switch_assert(mask < 8);        /* if pack->over this will allways be true */
                        this_byte &= SWITCH_REVERSE_BITPACKED_MASKS[mask];
                        this_byte >>= mask;

                        *pack->cur <<= pack->over;
                        *pack->cur |= this_byte;
                        pack->cur++;
                }


                pack->bytes++;
                pack->over = pack->under = 0;
        }
}

pack_check_over

(

unpack

)

while

(

unpack->bits_cur<=

SWITCH_BITS_PER_BYTE

)

Definition at line 167 of file switch_bitpack.h.

References switch_bitpack_t::bits_cur, switch_bitpack_t::bytes, switch_bitpack_t::cur, switch_bitpack_t::frame_bits, switch_bitpack_t::mode, switch_bitpack_t::over, SWITCH_BITPACK_MODE_RFC3551, SWITCH_BITS_PER_BYTE, this_byte, switch_bitpack_t::this_byte, and switch_bitpack_t::under.

Referenced by switch_xml_child(), and timesub().

                                                         {
                switch_byte_t next = unpack->bits_cur + unpack->frame_bits;
                switch_byte_t under_in;
                switch_byte_t mask;
                this_byte = unpack->this_byte;

                if (next > SWITCH_BITS_PER_BYTE) {
                        unpack->over = next - SWITCH_BITS_PER_BYTE;
                        unpack->under = unpack->frame_bits - unpack->over;

                        if (unpack->mode == SWITCH_BITPACK_MODE_RFC3551) {
                                mask = SWITCH_BITS_PER_BYTE - unpack->under;

                                under_in = this_byte & SWITCH_REVERSE_BITPACKED_MASKS[mask];
                                under_in >>= mask;
                                *unpack->cur |= under_in;
                        } else {
                                mask = unpack->under;
                                under_in = this_byte & SWITCH_BITPACKED_MASKS[mask];
                                *unpack->cur <<= mask;
                                *unpack->cur |= under_in;
                        }

                        break;
                }

                if (unpack->mode == SWITCH_BITPACK_MODE_RFC3551) {
                        this_byte >>= unpack->bits_cur;
                        this_byte &= SWITCH_BITPACKED_MASKS[unpack->frame_bits];
                        *unpack->cur |= this_byte;
                        unpack->cur++;
                } else {
                        this_byte >>= (SWITCH_BITS_PER_BYTE - next);
                        this_byte &= SWITCH_BITPACKED_MASKS[unpack->frame_bits];

                        *unpack->cur |= this_byte;
                        unpack->cur++;
                }

                unpack->bits_cur = next;
                unpack->bytes++;


        }

Variable Documentation

switch_byte_t bitlen

Definition at line 76 of file switch_bitpack.h.

unpack bits_cur = 0

Definition at line 161 of file switch_bitpack.h.

pack bits_tot = pack->frame_bits

Definition at line 232 of file switch_bitpack.h.

pack buf = buf

Definition at line 76 of file switch_bitpack.h.

Referenced by collect_thread_run(), do_dtls(), expand_vars(), get_addr(), get_addr6(), handle_ice(), ice_out(), inband_dtmf_generate_callback(), main(), play_and_collect(), preprocess(), preprocess_exec(), read_displace_callback(), reincarnate_protect(), separate_string_blank_delim(), separate_string_char_delim(), switch_amp_encode(), switch_channel_event_set_extended_data(), switch_console_complete(), switch_console_stream_write(), switch_core_asr_open(), switch_core_media_gen_local_sdp(), switch_core_media_sdp_map(), switch_core_media_set_r_sdp_codec_string(), switch_core_media_set_udptl_image_sdp(), switch_core_speech_open(), switch_dir_next_file(), switch_escape_string_pool(), switch_event_serialize(), switch_fd_read_dline(), switch_fd_read_line(), switch_fp_read_dline(), switch_get_addr(), switch_ivr_eavesdrop_session(), switch_ivr_originate(), switch_loadable_module_get_codecs_sorted(), switch_nat_multicast_runtime(), switch_parse_codec_buf(), switch_print_host(), switch_say_file(), switch_separate_string_string(), switch_simple_email(), switch_speex_decode(), switch_speex_encode(), switch_strerror_r(), switch_stun_host_lookup(), switch_stun_lookup(), switch_stun_packet_attribute_add_controlled(), switch_stun_packet_attribute_add_controlling(), switch_stun_packet_build_header(), switch_url_encode_opt(), switch_uuid_format(), switch_uuid_str(), switch_vasprintf(), switch_xml_parse_section_string(), switch_xml_toxml_buf(), teletone_handler(), video_bug_thread(), video_helper_thread(), video_write_thread(), vxprintf(), and write_displace_callback().

pack buflen = buflen

Definition at line 76 of file switch_bitpack.h.

Referenced by switch_ivr_originate(), switch_ivr_play_file(), switch_vasprintf(), switch_xml_toxml_buf(), teletone_handler(), teletone_init_session(), video_bug_thread(), video_helper_thread(), and video_write_thread().

pack cur = pack->buf

Definition at line 88 of file switch_bitpack.h.

Referenced by comp_callback(), preprocess(), switch_console_free_matches(), switch_core_file_seek(), switch_core_media_bug_remove_callback(), switch_core_media_bug_transfer_callback(), switch_core_remove_state_handler(), switch_dow_cmp(), switch_fd_read_dline(), switch_fd_read_line(), switch_fulldate_cmp(), switch_ivr_play_file(), switch_ivr_schedule_broadcast(), switch_ivr_schedule_transfer(), switch_live_array_clear(), switch_live_array_del(), switch_parse_codec_buf(), switch_tod_cmp(), switch_xml_cut(), switch_xml_insert(), and teletone_run().

else

Initial value:

{

                if (pack->mode == SWITCH_BITPACK_MODE_RFC3551) {
                        in <<= pack->shiftby;
                        *pack->cur |= in;
                        pack->shiftby = (switch_byte_t) (pack->shiftby + pack->frame_bits);
                } else {
                        *pack->cur <<= pack->frame_bits;
                        *pack->cur |= in;
                }

                if (next == SWITCH_BITS_PER_BYTE) {
                        pack->cur++;
                        pack->bytes++;
                        pack->bits_cur = pack->shiftby = 0;
                } else {
                        pack->bits_cur = (switch_byte_t) next;
                }
        }

        return 0

Definition at line 258 of file switch_bitpack.h.

pack frame_bits = bitlen

Definition at line 85 of file switch_bitpack.h.

switch_byte_t in

Initial value:

{
        switch_byte_t this_byte

Definition at line 154 of file switch_bitpack.h.

Referenced by skip(), switch_channel_expand_variables_check(), switch_cut_path(), switch_escape_char(), switch_event_expand_headers_check(), switch_simple_email(), switch_split_user_domain(), switch_strchr_strict(), switch_strip_commas(), and switch_strip_nonnumerics().

pack mode

Initial value:

{
        if (!pack || (bitlen > SWITCH_BITS_PER_BYTE) || !buf || !buflen) {
                return -1;
        }

        memset(pack, 0, sizeof(*pack))

Definition at line 78 of file switch_bitpack.h.

Referenced by switch_speex_fmtp_parse(), and switch_speex_init().

return

Definition at line 91 of file switch_bitpack.h.

const uint8_t SWITCH_BITPACKED_MASKS[] = { 0, 1, 3, 7, 15, 31, 63, 127, 255 }

static

Definition at line 64 of file switch_bitpack.h.

const uint8_t SWITCH_REVERSE_BITPACKED_MASKS[] = { 255, 254, 252, 248, 240, 224, 192, 128 }

static

Definition at line 65 of file switch_bitpack.h.

unpack this_byte = this_byte = in

Definition at line 162 of file switch_bitpack.h.

Referenced by pack_check_over(), and while().