dali/bacnet_stack
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
dfbc130dad27f9f779a7470d579410b2ee4d6cdd
bacnet_stack/bacnet-stack/bacdcode.c
T
skarg dfbc130dad fixed comment.
2005-04-17 01:35:16 +00:00

1615 lines
45 KiB
C
Raw Blame History

/*####COPYRIGHTBEGIN####
-------------------------------------------
Copyright (C) 2004 Steve Karg
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.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA.
As a special exception, if other files instantiate templates or
use macros or inline functions from this file, or you compile
this file and link it with other works to produce a work based
on this file, this file does not by itself cause the resulting
work to be covered by the GNU General Public License. However
the source code for this file must still be made available in
accordance with section (3) of the GNU General Public License.
This exception does not invalidate any other reasons why a work
based on this file might be covered by the GNU General Public
License.
-------------------------------------------
####COPYRIGHTEND####*/
#include <string.h>
#include "bacdef.h"
#include "bacdcode.h"
#include "bacenum.h"
#include "bits.h"
#include "bigend.h"
// NOTE: byte order plays a role in decoding multibyte values
// http://www.unixpapa.com/incnote/byteorder.html
/* max-segments-accepted
B'000' Unspecified number of segments accepted.
B'001' 2 segments accepted.
B'010' 4 segments accepted.
B'011' 8 segments accepted.
B'100' 16 segments accepted.
B'101' 32 segments accepted.
B'110' 64 segments accepted.
B'111' Greater than 64 segments accepted.
*/
/* max-APDU-length-accepted
B'0000' Up to MinimumMessageSize (50 octets)
B'0001' Up to 128 octets
B'0010' Up to 206 octets (fits in a LonTalk frame)
B'0011' Up to 480 octets (fits in an ARCNET frame)
B'0100' Up to 1024 octets
B'0101' Up to 1476 octets (fits in an ISO 8802-3 frame)
B'0110' reserved by ASHRAE
B'0111' reserved by ASHRAE
B'1000' reserved by ASHRAE
B'1001' reserved by ASHRAE
B'1010' reserved by ASHRAE
B'1011' reserved by ASHRAE
B'1100' reserved by ASHRAE
B'1101' reserved by ASHRAE
B'1110' reserved by ASHRAE
B'1111' reserved by ASHRAE
*/
// from clause 20.1.2.4 max-segments-accepted
// and clause 20.1.2.5 max-APDU-length-accepted
// returns the encoded octet
uint8_t encode_max_segs_max_apdu(int max_segs, int max_apdu)
{
uint8_t octet = 0;
if (max_segs < 2)
octet = 0;
else if (max_segs < 4)
octet = 0x10;
else if (max_segs < 8)
octet = 0x20;
else if (max_segs < 16)
octet = 0x30;
else if (max_segs < 32)
octet = 0x40;
else if (max_segs < 64)
octet = 0x50;
else if (max_segs == 64)
octet = 0x60;
else
octet = 0x70;
// max_apdu must be 50 octets minimum
if (max_apdu <= 50)
octet |= 0x00;
else if (max_apdu <= 128)
octet |= 0x01;
//fits in a LonTalk frame
else if (max_apdu <= 206)
octet |= 0x02;
//fits in an ARCNET or MS/TP frame
else if (max_apdu <= 480)
octet |= 0x03;
else if (max_apdu <= 1024)
octet |= 0x04;
// fits in an ISO 8802-3 frame
else if (max_apdu <= 1476)
octet |= 0x05;
return octet;
}
// from clause 20.1.2.4 max-segments-accepted
// and clause 20.1.2.5 max-APDU-length-accepted
// returns the encoded octet
int decode_max_segs(uint8_t octet)
{
int max_segs = 0;
switch (octet & 0xF0)
{
case 0:
max_segs = 0;
break;
case 0x10:
max_segs = 2;
break;
case 0x20:
max_segs = 4;
break;
case 0x30:
max_segs = 8;
break;
case 0x40:
max_segs = 16;
break;
case 0x50:
max_segs = 32;
break;
case 0x60:
max_segs = 64;
break;
case 0x70:
max_segs = 65;
break;
default:
break;
}
return max_segs;
}
int decode_max_apdu(uint8_t octet)
{
int max_apdu = 0;
switch (octet & 0x0F)
{
case 0:
max_apdu = 50;
break;
case 1:
max_apdu = 128;
break;
case 2:
max_apdu = 206;
break;
case 3:
max_apdu = 480;
break;
case 4:
max_apdu = 1024;
break;
case 5:
max_apdu = 1476;
break;
default:
break;
}
return max_apdu;
}
int encode_unsigned16(uint8_t * apdu, uint16_t value)
{
union {
uint8_t byte[2];
uint16_t value;
} short_data = {{0}};
short_data.value = value;
if (big_endian()) {
apdu[0] = short_data.byte[0];
apdu[1] = short_data.byte[1];
} else {
apdu[0] = short_data.byte[1];
apdu[1] = short_data.byte[0];
}
return 2;
}
int decode_unsigned16(uint8_t * apdu, uint16_t *value)
{
union {
uint8_t byte[2];
uint16_t value;
} short_data = {{0}};
if (big_endian()) {
short_data.byte[0] = apdu[0];
short_data.byte[1] = apdu[1];
} else {
short_data.byte[1] = apdu[0];
short_data.byte[0] = apdu[1];
}
if (value)
*value = short_data.value;
return 2;
}
int encode_unsigned32(uint8_t * apdu, uint32_t value)
{
union {
uint8_t byte[4];
uint32_t value;
} long_data = {{0}};
long_data.value = value;
if (big_endian()) {
apdu[0] = long_data.byte[0];
apdu[1] = long_data.byte[1];
apdu[2] = long_data.byte[2];
apdu[3] = long_data.byte[3];
} else {
apdu[0] = long_data.byte[3];
apdu[1] = long_data.byte[2];
apdu[2] = long_data.byte[1];
apdu[3] = long_data.byte[0];
}
return 4;
}
int decode_unsigned32(uint8_t * apdu, uint32_t *value)
{
union {
uint8_t byte[4];
uint32_t value;
} long_data = {{0}};
if (big_endian()) {
long_data.byte[0] = apdu[0];
long_data.byte[1] = apdu[1];
long_data.byte[2] = apdu[2];
long_data.byte[3] = apdu[3];
} else {
long_data.byte[3] = apdu[0];
long_data.byte[2] = apdu[1];
long_data.byte[1] = apdu[2];
long_data.byte[0] = apdu[3];
}
if (value)
*value = long_data.value;
return 4;
}
void bitstring_init(BACNET_BIT_STRING *bit_string)
{
int i;
bit_string->bits_used = 0;
for (i = 0; i < MAX_BITSTRING_BYTES; i++)
{
bit_string->value[i] = 0;
}
}
void bitstring_set_bit(BACNET_BIT_STRING *bit_string, uint8_t bit, bool value)
{
uint8_t byte_number = bit/8;
uint8_t bit_mask = 1;
if (byte_number < MAX_BITSTRING_BYTES)
{
// set max bits used
if (bit_string->bits_used < (bit + 1))
bit_string->bits_used = bit + 1;
bit_mask = bit_mask << (bit - (byte_number * 8));
if (value)
bit_string->value[byte_number] |= bit_mask;
else
bit_string->value[byte_number] &= (~(bit_mask));
}
}
bool bitstring_bit(BACNET_BIT_STRING *bit_string, uint8_t bit)
{
bool value = false;
uint8_t byte_number = bit/8;
uint8_t bit_mask = 1;
if (bit < (MAX_BITSTRING_BYTES * 8))
{
bit_mask = bit_mask << (bit - (byte_number * 8));
if (bit_string->value[byte_number] & bit_mask)
value = true;
}
return value;
}
uint8_t bitstring_bits_used(BACNET_BIT_STRING *bit_string)
{
return bit_string->bits_used;
}
// from clause 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tag(uint8_t * apdu, uint8_t tag_number, bool context_specific,
uint32_t len_value_type)
{
int len = 1; // return value
apdu[0] = 0;
if (context_specific)
apdu[0] = BIT3;
// additional tag byte after this byte
// for extended tag byte
if (tag_number <= 14)
apdu[0] |= (tag_number << 4);
else {
apdu[0] |= 0xF0;
apdu[1] = tag_number;
len++;
}
// NOTE: additional len byte(s) after extended tag byte
// if larger than 4
if (len_value_type <= 4)
apdu[0] |= len_value_type;
else {
apdu[0] |= 5;
if (len_value_type <= 253) {
apdu[len++] = len_value_type;
} else if (len_value_type <= 65535) {
apdu[len++] = 254;
len += encode_unsigned16(&apdu[len], len_value_type);
} else {
apdu[len++] = 255;
len += encode_unsigned32(&apdu[len], len_value_type);
}
}
return len;
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
int encode_opening_tag(uint8_t * apdu, uint8_t tag_number)
{
int len = 1;
apdu[0] = BIT3;
// additional tag byte after this byte for extended tag byte
if (tag_number <= 14)
apdu[0] |= (tag_number << 4);
else {
apdu[0] |= 0xF0;
apdu[1] = tag_number;
len++;
}
// type indicates opening tag
apdu[0] |= 6;
return len;
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
int encode_closing_tag(uint8_t * apdu, uint8_t tag_number)
{
int len = 1;
apdu[0] = BIT3;
// additional tag byte after this byte for extended tag byte
if (tag_number <= 14)
apdu[0] |= (tag_number << 4);
else {
apdu[0] |= 0xF0;
apdu[1] = tag_number;
len++;
}
// type indicates closing tag
apdu[0] |= 7;
return len;
}
// from clause 20.2.1.3.2 Constructed Data
// returns true if extended tag numbering is used
static bool decode_is_extended_tag_number(uint8_t * apdu)
{
return ((apdu[0] & 0xF0) == 0xF0);
}
// from clause 20.2.1.3.2 Constructed Data
// returns true if the extended value is used
static bool decode_is_extended_value(uint8_t * apdu)
{
return ((apdu[0] & 0x07) == 5);
}
// from clause 20.2.1.3.2 Constructed Data
// returns true if the tag is context specific
bool decode_is_context_specific(uint8_t * apdu)
{
return ((apdu[0] & BIT3) == BIT3);
}
int decode_tag_number(uint8_t * apdu, uint8_t * tag_number)
{
int len = 1; // return value
// decode the tag number first
if (decode_is_extended_tag_number(&apdu[0])) {
// extended tag
if (tag_number)
*tag_number = apdu[1];
len++;
} else {
if (tag_number)
*tag_number = (apdu[0] >> 4);
}
return len;
}
static bool decode_is_opening_tag(uint8_t * apdu)
{
return ((apdu[0] & 0x07) == 6);
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
static bool decode_is_closing_tag(uint8_t * apdu)
{
return ((apdu[0] & 0x07) == 7);
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
int decode_tag_number_and_value(uint8_t * apdu,
uint8_t * tag_number, uint32_t * value)
{
int len = 1;
uint16_t value16;
uint32_t value32;
len = decode_tag_number(&apdu[0], tag_number);
// decode the value
if (decode_is_extended_value(&apdu[0])) {
// tagged as uint32_t
if (apdu[len] == 255) {
len++;
len += decode_unsigned32(&apdu[len], &value32);
if (value)
*value = value32;
}
// tagged as uint16_t
else if (apdu[len] == 254) {
len++;
len += decode_unsigned16(&apdu[len], &value16);
if (value)
*value = value16;
}
// no tag - must be uint8_t
else {
if (value)
*value = apdu[len];
len++;
}
} else if (decode_is_opening_tag(&apdu[0]) && value)
*value = 0;
// closing tag
else if (decode_is_closing_tag(&apdu[0]) && value)
*value = 0;
// small value
else if (value)
*value = apdu[0] & 0x07;
return len;
}
// from clause 20.2.1.3.2 Constructed Data
// returns true if the tag is context specific and matches
bool decode_is_context_tag(uint8_t * apdu, uint8_t tag_number)
{
uint8_t my_tag_number = 0;
bool context_specific = false;
context_specific = decode_is_context_specific(apdu);
decode_tag_number(apdu, &my_tag_number);
return (context_specific && (my_tag_number == tag_number));
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
bool decode_is_opening_tag_number(uint8_t * apdu, uint8_t tag_number)
{
uint8_t my_tag_number = 0;
bool opening_tag = false;
opening_tag = ((apdu[0] & 0x07) == 6);
decode_tag_number(apdu, &my_tag_number);
return (opening_tag && (my_tag_number == tag_number));
}
// from clause 20.2.1.3.2 Constructed Data
// returns the number of apdu bytes consumed
bool decode_is_closing_tag_number(uint8_t * apdu, uint8_t tag_number)
{
uint8_t my_tag_number = 0;
bool closing_tag = false;
closing_tag = ((apdu[0] & 0x07) == 7);
decode_tag_number(apdu, &my_tag_number);
return (closing_tag && (my_tag_number == tag_number));
}
static uint8_t byte_reverse_bits(uint8_t in_byte)
{
uint8_t out_byte = 0;
if (in_byte & BIT0)
out_byte |= BIT7;
if (in_byte & BIT1)
out_byte |= BIT6;
if (in_byte & BIT2)
out_byte |= BIT5;
if (in_byte & BIT3)
out_byte |= BIT4;
if (in_byte & BIT4)
out_byte |= BIT3;
if (in_byte & BIT5)
out_byte |= BIT2;
if (in_byte & BIT6)
out_byte |= BIT1;
if (in_byte & BIT7)
out_byte |= BIT0;
return out_byte;
}
// from clause 20.2.10 Encoding of a Bit String Value
// returns the number of apdu bytes consumed
int decode_bitstring(uint8_t * apdu, uint32_t len_value,
BACNET_BIT_STRING *bit_string)
{
int len = 0;
uint8_t unused_bits = 0;
uint32_t i = 0;
uint32_t bytes_used = 0;
bitstring_init(bit_string);
if (len_value)
{
// the first octet contains the unused bits
bytes_used = len_value - 1;
if (bytes_used <= MAX_BITSTRING_BYTES)
{
len = 1;
for (i = 0; i < bytes_used; i++)
{
bit_string->value[i] = byte_reverse_bits(apdu[len++]);
}
unused_bits = apdu[0] & 0x07;
bit_string->bits_used = bytes_used * 8;
bit_string->bits_used -= unused_bits;
}
}
return len;
}
// returns the number of bytes that a bit string is using
static int bitstring_bytes_used(BACNET_BIT_STRING *bit_string)
{
int len = 0; // return value
uint8_t used_bytes = 0;
uint8_t last_bit = 0;
if (bit_string->bits_used)
{
last_bit = bit_string->bits_used - 1;
used_bytes = last_bit / 8;
// add one for the first byte
used_bytes++;
len = used_bytes;
}
return len;
}
// from clause 20.2.10 Encoding of a Bit String Value
// returns the number of apdu bytes consumed
int encode_bitstring(uint8_t * apdu, BACNET_BIT_STRING *bit_string)
{
int len = 0;
uint8_t remaining_used_bits = 0;
uint8_t used_bytes = 0;
uint8_t i = 0;
// if the bit string is empty, then the first octet shall be zero
if (bit_string->bits_used == 0)
apdu[len++] = 0;
else
{
used_bytes = bitstring_bytes_used(bit_string);
remaining_used_bits = bit_string->bits_used - ((used_bytes - 1) * 8);
// number of unused bits in the subsequent final octet
apdu[len++] = 8 - remaining_used_bits;
for (i = 0; i < used_bytes; i++)
{
apdu[len++] = byte_reverse_bits(bit_string->value[i]);
}
}
return len;
}
int encode_tagged_bitstring(uint8_t * apdu, BACNET_BIT_STRING *bit_string)
{
int len = 0;
int bit_string_encoded_length = 1;// 1 for the bits remaining octet
// bit string may use more than 1 octet for the tag, so find out how many
bit_string_encoded_length += bitstring_bytes_used(bit_string);
len = encode_tag(&apdu[0], BACNET_APPLICATION_TAG_BIT_STRING, false,
bit_string_encoded_length);
len += encode_bitstring(&apdu[len], bit_string);
return len;
}
// from clause 20.2.6 Encoding of a Real Number Value
// returns the number of apdu bytes consumed
int decode_real(uint8_t * apdu, float *real_value)
{
union {
uint8_t byte[4];
float real_value;
} my_data;
if (big_endian()) {
my_data.byte[0] = apdu[0];
my_data.byte[1] = apdu[1];
my_data.byte[2] = apdu[2];
my_data.byte[3] = apdu[3];
} else {
my_data.byte[0] = apdu[3];
my_data.byte[1] = apdu[2];
my_data.byte[2] = apdu[1];
my_data.byte[3] = apdu[0];
}
*real_value = my_data.real_value;
return 4;
}
// from clause 20.2.6 Encoding of a Real Number Value
// returns the number of apdu bytes consumed
int encode_bacnet_real(float value, uint8_t * apdu)
{
union {
uint8_t byte[4];
float real_value;
} my_data;
my_data.real_value = value;
if (big_endian()) {
apdu[0] = my_data.byte[0];
apdu[1] = my_data.byte[1];
apdu[2] = my_data.byte[2];
apdu[3] = my_data.byte[3];
} else {
apdu[0] = my_data.byte[3];
apdu[1] = my_data.byte[2];
apdu[2] = my_data.byte[1];
apdu[3] = my_data.byte[0];
}
return 4;
}
// from clause 20.2.6 Encoding of a Real Number Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_real(uint8_t * apdu, float value)
{
int len = 0;
// assumes that the tag only consumes 1 octet
len = encode_bacnet_real(value, &apdu[1]);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_REAL, false, len);
return len;
}
// from clause 20.2.14 Encoding of an Object Identifier Value
// returns the number of apdu bytes consumed
int decode_object_id(
uint8_t *apdu,
int *object_type,
uint32_t *instance)
{
uint32_t value = 0;
int len = 0;
len = decode_unsigned32(apdu,&value);
*object_type = ((value >> 22) & 0x3FF);
*instance = (value & 0x3FFFFF);
return len;
}
// from clause 20.2.14 Encoding of an Object Identifier Value
// returns the number of apdu bytes consumed
int encode_bacnet_object_id(
uint8_t * apdu,
int object_type,
uint32_t instance)
{
uint32_t value = 0;
uint32_t type = 0;
int len = 0;
type = object_type;
value = ((type & 0x3FF) << 22) | (instance & 0x3FFFFF);
len = encode_unsigned32(apdu,value);
return len;
}
// from clause 20.2.14 Encoding of an Object Identifier Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_context_object_id(
uint8_t * apdu,
int tag_number,
int object_type,
uint32_t instance)
{
int len = 0;
// assumes that the tag only consumes 1 octet
len = encode_bacnet_object_id(&apdu[1], object_type, instance);
len += encode_tag(&apdu[0], tag_number, true, len);
return len;
}
// from clause 20.2.14 Encoding of an Object Identifier Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_object_id(
uint8_t * apdu,
int object_type,
uint32_t instance)
{
int len = 0;
// assumes that the tag only consumes 1 octet
len = encode_bacnet_object_id(&apdu[1], object_type, instance);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_OBJECT_ID,
false, len);
return len;
}
// from clause 20.2.9 Encoding of a Character String Value
// returns the number of apdu bytes consumed
int encode_bacnet_string(uint8_t * apdu, const char *char_string, int len)
{
int i;
// limit - 6 octets is the most our tag and type could be
if (len > (MAX_APDU - 6))
len = MAX_APDU - 6;
for (i = 0; i < len; i++) {
apdu[1 + i] = char_string[i];
}
apdu[0] = CHARACTER_ANSI;
len++;
return len;
}
// from clause 20.2.9 Encoding of a Character String Value
// returns the number of apdu bytes consumed
int encode_bacnet_character_string(uint8_t * apdu, const char *char_string)
{
int len;
len = strlen(char_string);
len = encode_bacnet_string(&apdu[0], char_string, len);
return len;
}
// from clause 20.2.9 Encoding of a Character String Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_character_string(uint8_t * apdu, const char *char_string)
{
int len = 0;
int string_len = 0;
// find the size of the apdu first - not necessarily effecient
// but reuses existing functions
string_len = encode_bacnet_character_string(&apdu[1], char_string);
len = encode_tag(&apdu[0], BACNET_APPLICATION_TAG_CHARACTER_STRING,
false, string_len);
if ((len + string_len) < MAX_APDU)
len += encode_bacnet_character_string(&apdu[len], char_string);
else
len = 0;
return len;
}
// from clause 20.2.9 Encoding of a Character String Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int decode_character_string(uint8_t * apdu, uint32_t len_value,
char *char_string, size_t string_len)
{
int len = 0, i = 0;
// FIXME: issue warning?
if (len_value > string_len)
len_value = string_len;
if (len_value) {
// decode ANSI X3.4
if (apdu[len] == 0) {
len++;
len_value--;
for (i = 0; i < len_value; i++) {
char_string[i] = apdu[len + i];
}
// terminate the c string
char_string[i] = 0;
len += len_value;
}
}
return len;
}
// from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
// FIXME: What about endian?
int encode_bacnet_unsigned(uint8_t * apdu, unsigned int value)
{
int len = 0; // return value
if (value < 0x100) {
apdu[0] = value;
len = 1;
} else if (value < 0x10000) {
apdu[0] = value / 0x100;
apdu[1] = value - (apdu[0] * 0x100);
len = 2;
} else if (value < 0x1000000) {
apdu[0] = value / 0x10000;
apdu[1] = (value - apdu[0] * 0x10000) / 0x100;
apdu[2] = value - (apdu[0] * 0x10000) - (apdu[1] * 0x100);
len = 3;
} else {
apdu[0] = value / 0x1000000;
apdu[1] = (value - (apdu[0] * 0x1000000)) / 0x10000;
apdu[2] =
(value - (apdu[0] * 0x1000000) - (apdu[1] * 0x10000)) / 0x100;
apdu[3] =
value - (apdu[0] * 0x1000000) - (apdu[1] * 0x10000) -
(apdu[2] * 0x100);
len = 4;
}
return len;
}
// from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_context_unsigned(uint8_t * apdu, int tag_number, int value)
{
int len = 0;
len = encode_bacnet_unsigned(&apdu[1], value);
len += encode_tag(&apdu[0], tag_number, true, len);
return len;
}
// from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_unsigned(uint8_t * apdu, unsigned int value)
{
int len = 0;
len = encode_bacnet_unsigned(&apdu[1], value);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_UNSIGNED_INT,
false, len);
return len;
}
// from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
// FIXME: What about endian?
int decode_unsigned(uint8_t * apdu, uint32_t len_value, unsigned *value)
{
int len = 0; // return value
if (value) {
switch (len_value) {
case 1:
*value = apdu[len];
break;
case 2:
*value = (apdu[len] * 0x100) + apdu[len + 1];
break;
case 3:
*value = (apdu[len] * 0x10000) +
(apdu[len + 1] * 0x100) + apdu[len + 2];
break;
case 4:
*value = (apdu[len] * 0x1000000) +
(apdu[len + 1] * 0x10000) + (apdu[len + 2] * 0x100) +
apdu[len + 3];
break;
default:
*value = 0;
break;
}
}
len += len_value;
return len;
}
// from clause 20.2.11 Encoding of an Enumerated Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int decode_enumerated(uint8_t * apdu, uint32_t len_value, int *value)
{
unsigned unsigned_value = 0;
int len;
len = decode_unsigned(apdu, len_value, &unsigned_value);
if (value)
*value = unsigned_value;
return len;
}
// from clause 20.2.11 Encoding of an Enumerated Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_bacnet_enumerated(uint8_t * apdu, int value)
{
return encode_bacnet_unsigned(apdu, value);
}
// from clause 20.2.11 Encoding of an Enumerated Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_enumerated(uint8_t * apdu, int value)
{
int len = 0; // return value
// assumes that the tag only consumes 1 octet
len = encode_bacnet_enumerated(&apdu[1], value);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_ENUMERATED,
false, len);
return len;
}
// from clause 20.2.11 Encoding of an Enumerated Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_context_enumerated(uint8_t * apdu, int tag_number, int value)
{
int len = 0; // return value
// assumes that the tag only consumes 1 octet
len = encode_bacnet_enumerated(&apdu[1], value);
len += encode_tag(&apdu[0], tag_number, true, len);
return len;
}
// from clause 20.2.5 Encoding of a Signed Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int decode_signed(uint8_t * apdu, uint32_t len_value, int *value)
{
int len = 0; // return value
if (value) {
switch (len_value) {
case 1:
*value = apdu[len];
break;
case 2:
*value = (apdu[len] * 0x100) + apdu[len + 1];
break;
case 3:
*value = (apdu[len] * 0x10000) +
(apdu[len + 1] * 0x100) + apdu[len + 2];
break;
case 4:
*value = (apdu[len] * 0x1000000) +
(apdu[len + 1] * 0x10000) + (apdu[len + 2] * 0x100) +
apdu[len + 3];
break;
default:
*value = 0;
break;
}
}
len += len_value;
return len;
}
// from clause 20.2.5 Encoding of a Signed Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_bacnet_signed(uint8_t * apdu, int value)
{
return encode_bacnet_unsigned(apdu, value);
}
// from clause 20.2.5 Encoding of a Signed Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_signed(uint8_t * apdu, int value)
{
int len = 0; // return value
// assumes that the tag only consumes 1 octet
len = encode_bacnet_signed(&apdu[1], value);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_SIGNED_INT,
false, len);
return len;
}
// from clause 20.2.5 Encoding of a Signed Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_context_signed(uint8_t * apdu, int tag_number, int value)
{
int len = 0; // return value
// assumes that the tag only consumes 1 octet
len = encode_bacnet_signed(&apdu[1], value);
len += encode_tag(&apdu[0], tag_number, true, len);
return len;
}
// from clause 20.2.13 Encoding of a Time Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_bacnet_time(uint8_t * apdu, int hour, int min, int sec,
int hundredths)
{
apdu[0] = hour;
apdu[1] = min;
apdu[2] = sec;
apdu[3] = hundredths;
return 4;
}
// from clause 20.2.13 Encoding of a Time Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_time(uint8_t * apdu, int hour, int min, int sec,
int hundredths)
{
int len = 0;
// assumes that the tag only consumes 1 octet
len = encode_bacnet_time(&apdu[1], hour, min, sec, hundredths);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_TIME, false, len);
return len;
}
// from clause 20.2.13 Encoding of a Time Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int decode_bacnet_time(uint8_t * apdu, int *hour, int *min, int *sec,
int *hundredths)
{
*hour = apdu[0];
*min = apdu[1];
*sec = apdu[2];
*hundredths = apdu[3];
return 4;
}
// BACnet Date
// year = years since 1900
// month 1=Jan
// day = day of month
// wday 1=Monday...7=Sunday
// from clause 20.2.12 Encoding of a Date Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_bacnet_date(uint8_t * apdu, int year, int month, int day,
int wday)
{
apdu[0] = year;
apdu[1] = month;
apdu[2] = day;
apdu[3] = wday;
return 4;
}
// from clause 20.2.12 Encoding of a Date Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int encode_tagged_date(uint8_t * apdu, int year, int month, int day,
int wday)
{
int len = 0;
// assumes that the tag only consumes 1 octet
len = encode_bacnet_date(&apdu[1], year, month, day, wday);
len += encode_tag(&apdu[0], BACNET_APPLICATION_TAG_DATE, false, len);
return len;
}
// from clause 20.2.12 Encoding of a Date Value
// and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed
int decode_date(uint8_t * apdu, int *year, int *month, int *day, int *wday)
{
*year = apdu[0];
*month = apdu[1];
*day = apdu[2];
*wday = apdu[3];
return 4;
}
/* end of decoding_encoding.c */
#ifdef TEST
#include <assert.h>
#include <string.h>
#include "ctest.h"
static int get_apdu_len(bool extended_tag, uint32_t value)
{
int test_len = 1;
if (extended_tag)
test_len++;
if (value <= 4)
test_len += 0; // do nothing...
else if (value <= 253)
test_len += 1;
else if (value <= 65535)
test_len += 3;
else
test_len += 5;
return test_len;
}
void testBACDCodeTags(Test * pTest)
{
uint8_t apdu[MAX_APDU] = { 0 };
uint8_t tag_number = 0, test_tag_number = 0;
int len = 0, test_len = 0;
uint32_t value = 0, test_value = 0;
for (tag_number = 0;; tag_number++) {
len = encode_opening_tag(&apdu[0], tag_number);
test_len =
get_apdu_len(decode_is_extended_tag_number(&apdu[0]), 0);
ct_test(pTest, len == test_len);
len =
decode_tag_number_and_value(&apdu[0], &test_tag_number,
&value);
ct_test(pTest, value == 0);
ct_test(pTest, len == test_len);
ct_test(pTest, tag_number == test_tag_number);
ct_test(pTest, decode_is_opening_tag(&apdu[0]) == true);
ct_test(pTest, decode_is_closing_tag(&apdu[0]) == false);
len = encode_closing_tag(&apdu[0], tag_number);
ct_test(pTest, len == test_len);
len =
decode_tag_number_and_value(&apdu[0], &test_tag_number,
&value);
ct_test(pTest, len == test_len);
ct_test(pTest, value == 0);
ct_test(pTest, tag_number == test_tag_number);
ct_test(pTest, decode_is_opening_tag(&apdu[0]) == false);
ct_test(pTest, decode_is_closing_tag(&apdu[0]) == true);
// test the len-value-type portion
for (value = 1;; value = value << 1) {
len = encode_tag(&apdu[0], tag_number, false, value);
len = decode_tag_number_and_value(&apdu[0], &test_tag_number,
&test_value);
ct_test(pTest, tag_number == test_tag_number);
ct_test(pTest, value == test_value);
test_len =
get_apdu_len(decode_is_extended_tag_number(&apdu[0]),
value);
ct_test(pTest, len == test_len);
// stop at the the last value
if (value & BIT31)
break;
}
// stop after the last tag number
if (tag_number == 255)
break;
}
return;
}
void testBACDCodeReal(Test * pTest)
{
uint8_t real_array[4] = { 0 };
uint8_t encoded_array[4] = { 0 };
float value = 42.123;
float decoded_value = 0;
uint8_t apdu[MAX_APDU] = { 0 };
int len = 0, apdu_len = 0;
uint8_t tag_number = 0;
uint32_t long_value = 0;
encode_bacnet_real(value, &real_array[0]);
decode_real(&real_array[0], &decoded_value);
ct_test(pTest, decoded_value == value);
encode_bacnet_real(value, &encoded_array[0]);
ct_test(pTest, memcmp(&real_array, &encoded_array,
sizeof(real_array)) == 0);
// a real will take up 4 octects plus a one octet tag
apdu_len = encode_tagged_real(&apdu[0], value);
ct_test(pTest, apdu_len == 5);
// len tells us how many octets were used for encoding the value
len = decode_tag_number_and_value(&apdu[0], &tag_number, &long_value);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_REAL);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == false);
ct_test(pTest, len == 1);
ct_test(pTest, long_value == 4);
decode_real(&apdu[len], &decoded_value);
ct_test(pTest, decoded_value == value);
return;
}
void testBACDCodeEnumerated(Test * pTest)
{
uint8_t array[5] = { 0 };
uint8_t encoded_array[5] = { 0 };
int value = 1;
int decoded_value = 0;
int i = 0, apdu_len = 0;
int len = 0;
uint8_t apdu[MAX_APDU] = { 0 };
uint8_t tag_number = 0;
uint32_t len_value = 0;
for (i = 0; i < 8; i++) {
apdu_len = encode_tagged_enumerated(&array[0], value);
len = decode_tag_number_and_value(&array[0], &tag_number, &len_value);
len += decode_enumerated(&array[len],len_value, &decoded_value);
ct_test(pTest, decoded_value == value);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_ENUMERATED);
ct_test(pTest, len == apdu_len);
// encode back the value
encode_tagged_enumerated(&encoded_array[0], decoded_value);
ct_test(pTest, memcmp(&array[0], &encoded_array[0],
sizeof(array)) == 0);
// an enumerated will take up to 4 octects
// plus a one octet for the tag
apdu_len = encode_tagged_enumerated(&apdu[0], value);
len = decode_tag_number_and_value(&apdu[0], &tag_number, NULL);
ct_test(pTest, len == 1);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_ENUMERATED);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == false);
// context specific encoding
apdu_len = encode_context_enumerated(&apdu[0], 3, value);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == true);
len = decode_tag_number_and_value(&apdu[0], &tag_number, NULL);
ct_test(pTest, len == 1);
ct_test(pTest, tag_number == 3);
// test the interesting values
value = value << 1;
}
return;
}
void testBACDCodeUnsigned(Test * pTest)
{
uint8_t array[5] = { 0 };
uint8_t encoded_array[5] = { 0 };
unsigned int value = 1;
unsigned int decoded_value = 0;
int i, len, apdu_len;
uint8_t apdu[MAX_APDU] = { 0 };
uint8_t tag_number = 0;
uint32_t len_value = 0;
for (i = 0; i < 8; i++) {
len_value = encode_tagged_unsigned(&array[0], value);
len = decode_tag_number_and_value(&array[0], &tag_number, &len_value);
len = decode_unsigned(&array[len], len_value, &decoded_value);
ct_test(pTest, decoded_value == value);
encode_tagged_unsigned(&encoded_array[0], decoded_value);
ct_test(pTest, memcmp(&array[0], &encoded_array[0],
sizeof(array)) == 0);
// an unsigned will take up to 4 octects
// plus a one octet for the tag
apdu_len = encode_tagged_unsigned(&apdu[0], value);
// apdu_len varies...
//ct_test(pTest, apdu_len == 5);
len = decode_tag_number_and_value(&apdu[0], &tag_number, NULL);
ct_test(pTest, len == 1);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_UNSIGNED_INT);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == false);
value = value << 1;
}
return;
}
void testBACDCodeSigned(Test * pTest)
{
uint8_t array[5] = { 0 };
uint8_t encoded_array[5] = { 0 };
int value = 1;
int decoded_value = 0;
int i = 0, len = 0, apdu_len = 0;
uint8_t apdu[MAX_APDU] = { 0 };
uint8_t tag_number = 0;
uint32_t len_value = 0;
for (i = 0; i < 8; i++) {
len = encode_tagged_signed(&array[0], value);
len = decode_tag_number_and_value(&array[0], &tag_number, &len_value);
len = decode_signed(&array[len], len_value, &decoded_value);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_SIGNED_INT);
ct_test(pTest, decoded_value == value);
encode_tagged_signed(&encoded_array[0], decoded_value);
ct_test(pTest, memcmp(&array[0], &encoded_array[0],
sizeof(array)) == 0);
// a signed int will take up to 4 octects
// plus a one octet for the tag
apdu_len = encode_tagged_signed(&apdu[0], value);
len = decode_tag_number_and_value(&apdu[0], &tag_number, NULL);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_SIGNED_INT);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == false);
value = value << 1;
}
value = -1;
apdu_len = encode_tagged_signed(&array[0], value);
len = decode_tag_number_and_value(&array[0], &tag_number, &len_value);
len += decode_signed(&array[len], len_value, &decoded_value);
ct_test(pTest, len == apdu_len);
ct_test(pTest, decoded_value == value);
encode_tagged_signed(&encoded_array[0], decoded_value);
ct_test(pTest, memcmp(&array[0], &encoded_array[0],
sizeof(array)) == 0);
// a signed int will take up to 4 octects
// plus a one octet for the tag
apdu_len = encode_tagged_signed(&apdu[0], value);
len = decode_tag_number_and_value(&apdu[0], &tag_number, NULL);
ct_test(pTest, len == 1);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_SIGNED_INT);
ct_test(pTest, decode_is_context_specific(&apdu[0]) == false);
return;
}
void testBACDCodeString(Test * pTest)
{
uint8_t array[MAX_APDU] = { 0 };
uint8_t encoded_array[MAX_APDU] = { 0 };
char test_string[MAX_APDU] = { "" };
char decoded_string[MAX_APDU] = { "" };
int i; // for loop counter
int apdu_len;
int len;
char *test_string0 = "";
uint8_t tag_number = 0;
uint32_t len_value = 0;
apdu_len = encode_tagged_character_string(&array[0], &test_string0[0]);
len = decode_tag_number_and_value(&array[0], &tag_number, &len_value);
len += decode_character_string(&array[len], len_value,
&decoded_string[0], sizeof(decoded_string));
ct_test(pTest, apdu_len == len);
ct_test(pTest, strcmp(&test_string0[0], &decoded_string[0]) == 0);
for (i = 0; i < (MAX_APDU - 6); i++) {
test_string[i] = 'S';
test_string[i + 1] = '\0';
apdu_len =
encode_tagged_character_string(&encoded_array[0],
&test_string[0]);
len = decode_tag_number_and_value(&encoded_array[0],
&tag_number, &len_value);
len += decode_character_string(&encoded_array[len], len_value,
&decoded_string[0], sizeof(decoded_string));
if (apdu_len != len) {
printf("test string=#%d\n", i);
}
ct_test(pTest, apdu_len == len);
if (strcmp(&test_string[0], &decoded_string[0]) != 0) {
printf("test string=#%d\n", i);
}
ct_test(pTest, strcmp(&test_string[0], &decoded_string[0]) == 0);
}
return;
}
void testBACDCodeObject(Test * pTest)
{
uint8_t object_array[4] = {
0
};
uint8_t encoded_array[4] = {
0
};
BACNET_OBJECT_TYPE type = OBJECT_BINARY_INPUT;
BACNET_OBJECT_TYPE decoded_type = OBJECT_ANALOG_OUTPUT;
int instance = 123;
uint32_t decoded_instance = 0;
encode_bacnet_object_id(&encoded_array[0], type, instance);
decode_object_id(&encoded_array[0],
(int *) &decoded_type, &decoded_instance);
ct_test(pTest, decoded_type == type);
ct_test(pTest, decoded_instance == instance);
encode_bacnet_object_id(&object_array[0], type, instance);
ct_test(pTest, memcmp(&object_array[0], &encoded_array[0],
sizeof(object_array)) == 0);
for (type = 0; type < 1024; type++) {
for (instance = 0; instance <= 0x3FFFFF; instance += 1024) {
encode_bacnet_object_id(&encoded_array[0], type, instance);
decode_object_id(&encoded_array[0],
(int *) &decoded_type, &decoded_instance);
ct_test(pTest, decoded_type == type);
ct_test(pTest, decoded_instance == instance);
encode_bacnet_object_id(&object_array[0], type, instance);
ct_test(pTest, memcmp(&object_array[0],
&encoded_array[0], sizeof(object_array)) == 0);
}
}
return;
}
void testBACDCodeMaxSegsApdu(Test * pTest)
{
int max_segs[8] = {0,2,4,8,16,32,64,65};
int max_apdu[6] = {50,128,206,480,1024,1476};
int i = 0;
int j = 0;
uint8_t octet = 0;
// test
for (i = 0; i < 8; i++)
{
for (j = 0; j < 6; j++)
{
octet = encode_max_segs_max_apdu(max_segs[i], max_apdu[j]);
ct_test(pTest, max_segs[i] == decode_max_segs(octet));
ct_test(pTest, max_apdu[j] == decode_max_apdu(octet));
}
}
}
void testBACDCodeBitString(Test * pTest)
{
uint8_t bit = 0;
BACNET_BIT_STRING bit_string;
BACNET_BIT_STRING decoded_bit_string;
uint8_t apdu[MAX_APDU] = { 0 };
uint32_t len_value = 0;
uint8_t tag_number = 0;
int len = 0;
bitstring_init(&bit_string);
// verify initialization
ct_test(pTest, bitstring_bits_used(&bit_string) == 0);
for (bit = 0; bit < (MAX_BITSTRING_BYTES*8); bit++)
{
ct_test(pTest, bitstring_bit(&bit_string, bit) == false);
}
// test encode/decode -- true
for (bit = 0; bit < (MAX_BITSTRING_BYTES*8); bit++)
{
bitstring_set_bit(&bit_string, bit, true);
ct_test(pTest, bitstring_bits_used(&bit_string) == (bit + 1));
ct_test(pTest, bitstring_bit(&bit_string, bit) == true);
// encode
len = encode_tagged_bitstring(&apdu[0], &bit_string);
// decode
len = decode_tag_number_and_value(&apdu[0], &tag_number, &len_value);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_BIT_STRING);
len += decode_bitstring(&apdu[len], len_value,&decoded_bit_string);
ct_test(pTest, bitstring_bits_used(&decoded_bit_string) == (bit + 1));
ct_test(pTest, bitstring_bit(&decoded_bit_string, bit) == true);
}
// test encode/decode -- false
bitstring_init(&bit_string);
for (bit = 0; bit < (MAX_BITSTRING_BYTES*8); bit++)
{
bitstring_set_bit(&bit_string, bit, false);
ct_test(pTest, bitstring_bits_used(&bit_string) == (bit + 1));
ct_test(pTest, bitstring_bit(&bit_string, bit) == false);
// encode
len = encode_tagged_bitstring(&apdu[0], &bit_string);
// decode
len = decode_tag_number_and_value(&apdu[0], &tag_number, &len_value);
ct_test(pTest, tag_number == BACNET_APPLICATION_TAG_BIT_STRING);
len += decode_bitstring(&apdu[len], len_value,&decoded_bit_string);
ct_test(pTest, bitstring_bits_used(&decoded_bit_string) == (bit + 1));
ct_test(pTest, bitstring_bit(&decoded_bit_string, bit) == false);
}
}
#ifdef TEST_DECODE
int main(void)
{
Test *pTest;
bool rc;
pTest = ct_create("BACDCode", NULL);
/* individual tests */
rc = ct_addTestFunction(pTest, testBACDCodeTags);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeReal);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeUnsigned);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeSigned);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeEnumerated);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeString);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeObject);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeMaxSegsApdu);
assert(rc);
rc = ct_addTestFunction(pTest, testBACDCodeBitString);
assert(rc);
// configure output
ct_setStream(pTest, stdout);
ct_run(pTest);
(void) ct_report(pTest);
ct_destroy(pTest);
return 0;
}
#endif /* TEST_DECODE */
#endif /* TEST */
Reference in New Issue View Git Blame Copy Permalink