refactored the encode and decode of unsigned16 and unsigned32.

This commit is contained in:
skarg
2005-03-16 16:17:35 +00:00
parent 1190ff8380
commit ceaae8ca5e
2 changed files with 101 additions and 131 deletions
+97 -130
View File
@@ -35,15 +35,12 @@
#include <string.h> #include <string.h>
#include <assert.h> #include <assert.h>
#include "bacdef.h"
#include "bacdcode.h" #include "bacdcode.h"
#include "bacenum.h" #include "bacenum.h"
#include "bits.h" #include "bits.h"
#include "bigend.h" #include "bigend.h"
#ifndef MAX_APDU
#define MAX_APDU 480
#endif
// NOTE: byte order plays a role in decoding multibyte values // NOTE: byte order plays a role in decoding multibyte values
// http://www.unixpapa.com/incnote/byteorder.html // http://www.unixpapa.com/incnote/byteorder.html
@@ -121,36 +118,91 @@ uint8_t encode_max_segs_max_apdu(int max_segs, int max_apdu)
return octet; return octet;
} }
int encode_bacnet_unsigned16(uint8_t * apdu, uint16_t value) int encode_unsigned16(uint8_t * apdu, uint16_t value)
{ {
int len = 0; // return value union {
uint8_t byte[2];
uint16_t value;
} short_data = {{0}};
if (value < 0x100) { short_data.value = value;
apdu[0] = value; if (big_endian()) {
apdu[1] = 0; apdu[0] = short_data.byte[0];
len = 2; apdu[1] = short_data.byte[1];
} else { } else {
apdu[0] = value / 0x100; apdu[0] = short_data.byte[1];
apdu[1] = value - (apdu[0] * 0x100); apdu[1] = short_data.byte[0];
len = 2;
} }
return len; return 2;
} }
int decode_unsigned16(uint8_t * apdu, uint16_t *value) int decode_unsigned16(uint8_t * apdu, uint16_t *value)
{ {
int len = 0; // return value union {
uint8_t byte[2];
uint16_t value;
} short_data = {{0}};
if (value) if (big_endian()) {
{ short_data.byte[0] = apdu[0];
*value = (apdu[len] * 0x100) + apdu[len + 1]; short_data.byte[1] = apdu[1];
len = 2; } else {
short_data.byte[1] = apdu[0];
short_data.byte[0] = apdu[1];
} }
if (value)
*value = short_data.value;
return len; 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;
}
// from clause 20.2.1 General Rules for Encoding BACnet Tags // from clause 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed // returns the number of apdu bytes consumed
@@ -158,16 +210,6 @@ int encode_tag(uint8_t * apdu, uint8_t tag_number, bool context_specific,
uint32_t len_value_type) uint32_t len_value_type)
{ {
int len = 1; // return value int len = 1; // return value
union {
uint8_t byte[2];
uint16_t value;
} short_data = { {
0}};
union {
uint8_t byte[4];
uint32_t value;
} long_data = { {
0}};
apdu[0] = 0; apdu[0] = 0;
if (context_specific) if (context_specific)
@@ -190,36 +232,13 @@ int encode_tag(uint8_t * apdu, uint8_t tag_number, bool context_specific,
else { else {
apdu[0] |= 5; apdu[0] |= 5;
if (len_value_type <= 253) { if (len_value_type <= 253) {
apdu[len] = len_value_type; apdu[len++] = len_value_type;
len++;
} else if (len_value_type <= 65535) { } else if (len_value_type <= 65535) {
apdu[len] = 254; apdu[len++] = 254;
len++; len += encode_unsigned16(&apdu[len], len_value_type);
short_data.value = len_value_type;
if (big_endian()) {
apdu[len + 0] = short_data.byte[0];
apdu[len + 1] = short_data.byte[1];
} else {
apdu[len + 0] = short_data.byte[1];
apdu[len + 1] = short_data.byte[0];
}
len += 2;
} else { } else {
apdu[len] = 255; apdu[len++] = 255;
len++; len += encode_unsigned32(&apdu[len], len_value_type);
long_data.value = len_value_type;
if (big_endian()) {
apdu[len + 0] = long_data.byte[0];
apdu[len + 1] = long_data.byte[1];
apdu[len + 2] = long_data.byte[2];
apdu[len + 3] = long_data.byte[3];
} else {
apdu[len + 0] = long_data.byte[3];
apdu[len + 1] = long_data.byte[2];
apdu[len + 2] = long_data.byte[1];
apdu[len + 3] = long_data.byte[0];
}
len += 4;
} }
} }
@@ -329,16 +348,8 @@ int decode_tag_number_and_value(uint8_t * apdu,
uint8_t * tag_number, uint32_t * value) uint8_t * tag_number, uint32_t * value)
{ {
int len = 1; int len = 1;
union { uint16_t value16;
uint8_t byte[2]; uint32_t value32;
uint16_t value;
} short_data = { {
0}};
union {
uint8_t byte[4];
uint32_t value;
} long_data = { {
0}};
len = decode_tag_number(&apdu[0], tag_number); len = decode_tag_number(&apdu[0], tag_number);
// decode the value // decode the value
@@ -346,36 +357,16 @@ int decode_tag_number_and_value(uint8_t * apdu,
// tagged as uint32_t // tagged as uint32_t
if (apdu[len] == 255) { if (apdu[len] == 255) {
len++; len++;
if (big_endian()) { len += decode_unsigned32(&apdu[len], &value32);
long_data.byte[0] = apdu[len + 0];
long_data.byte[1] = apdu[len + 1];
long_data.byte[2] = apdu[len + 2];
long_data.byte[3] = apdu[len + 3];
} else {
long_data.byte[3] = apdu[len + 0];
long_data.byte[2] = apdu[len + 1];
long_data.byte[1] = apdu[len + 2];
long_data.byte[0] = apdu[len + 3];
}
if (value) if (value)
*value = long_data.value; *value = value32;
len += 4;
} }
// tagged as uint16_t // tagged as uint16_t
else if (apdu[len] == 254) { else if (apdu[len] == 254) {
len++; len++;
if (big_endian()) { len += decode_unsigned16(&apdu[len], &value16);
short_data.byte[0] = apdu[len + 0];
short_data.byte[1] = apdu[len + 1];
} else {
short_data.byte[1] = apdu[len + 0];
short_data.byte[0] = apdu[len + 1];
}
if (value) if (value)
*value = short_data.value; *value = value16;
len += 2;
} }
// no tag - must be uint8_t // no tag - must be uint8_t
else { else {
@@ -502,55 +493,29 @@ int encode_tagged_real(uint8_t * apdu, float value)
// from clause 20.2.14 Encoding of an Object Identifier Value // from clause 20.2.14 Encoding of an Object Identifier Value
// returns the number of apdu bytes consumed // returns the number of apdu bytes consumed
int decode_object_id(uint8_t * apdu, int *object_type, uint32_t *instance) int decode_object_id(uint8_t *apdu, int *object_type, uint32_t *instance)
{ {
union { uint32_t value = 0;
uint8_t byte[4]; int len = 0;
uint32_t value;
} my_data;
if (big_endian()) { len = decode_unsigned32(apdu,&value);
my_data.byte[0] = apdu[0]; *object_type = ((value >> 22) & 0x3FF);
my_data.byte[1] = apdu[1]; *instance = (value & 0x3FFFFF);
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];
}
*object_type = ((my_data.value >> 22) & 0x3FF); return len;
*instance = (my_data.value & 0x3FFFFF);
return 4;
} }
// from clause 20.2.14 Encoding of an Object Identifier Value // from clause 20.2.14 Encoding of an Object Identifier Value
// returns the number of apdu bytes consumed // returns the number of apdu bytes consumed
int encode_bacnet_object_id(uint8_t * apdu, int object_type, uint32_t instance) int encode_bacnet_object_id(uint8_t * apdu, int object_type, uint32_t instance)
{ {
union { uint32_t value = 0;
uint8_t byte[4]; int len = 0;
uint32_t value;
} my_data;
my_data.value = ((object_type & 0x3FF) << 22) | (instance & 0x3FFFFF); value = ((object_type & 0x3FF) << 22) | (instance & 0x3FFFFF);
len = encode_unsigned32(apdu,value);
if (big_endian()) { return len;
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 20.2.14 Encoding of an Object Identifier Value // from clause 20.2.14 Encoding of an Object Identifier Value
@@ -664,6 +629,7 @@ int decode_character_string(uint8_t * apdu, uint32_t len_value,
// from clause 20.2.4 Encoding of an Unsigned Integer Value // from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags // and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed // returns the number of apdu bytes consumed
// FIXME: What about endian?
int encode_bacnet_unsigned(uint8_t * apdu, unsigned int value) int encode_bacnet_unsigned(uint8_t * apdu, unsigned int value)
{ {
int len = 0; // return value int len = 0; // return value
@@ -724,6 +690,7 @@ int encode_tagged_unsigned(uint8_t * apdu, unsigned int value)
// from clause 20.2.4 Encoding of an Unsigned Integer Value // from clause 20.2.4 Encoding of an Unsigned Integer Value
// and 20.2.1 General Rules for Encoding BACnet Tags // and 20.2.1 General Rules for Encoding BACnet Tags
// returns the number of apdu bytes consumed // returns the number of apdu bytes consumed
// FIXME: What about endian?
int decode_unsigned(uint8_t * apdu, uint32_t len_value, unsigned *value) int decode_unsigned(uint8_t * apdu, uint32_t len_value, unsigned *value)
{ {
int len = 0; // return value int len = 0; // return value
+4 -1
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@@ -136,8 +136,11 @@ int decode_date(uint8_t * apdu, int *year, int *month, int *day,
int *wday); int *wday);
// two octet unsigned16 // two octet unsigned16
int encode_bacnet_unsigned16(uint8_t * apdu, uint16_t value); int encode_unsigned16(uint8_t * apdu, uint16_t value);
int decode_unsigned16(uint8_t * apdu, uint16_t *value); int decode_unsigned16(uint8_t * apdu, uint16_t *value);
// four octet unsigned32
int encode_unsigned32(uint8_t * apdu, uint32_t value);
int decode_unsigned32(uint8_t * apdu, uint32_t *value);
// from clause 20.1.2.4 max-segments-accepted // from clause 20.1.2.4 max-segments-accepted
// and clause 20.1.2.5 max-APDU-length-accepted // and clause 20.1.2.5 max-APDU-length-accepted