ASCII art diagram converter: Difference between revisions
Added C++ implementation
(add task to aarch64 assembly raspberry pi or android) |
(Added C++ implementation) |
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Name NSCOUNT value : 0001101111110001
Name ARCOUNT value : 0110100110100100
</pre>
=={{header|C++}}==
<lang cpp>#include <array>
#include <bitset>
#include <iostream>
using namespace std;
struct FieldDetails {string_view Name; int NumBits;};
// parses the ASCII diagram and returns the field name, bit sizes, and the
// total byte size
template <const char *T> consteval auto ParseDiagram()
{
// trim the ASCII diagram text
constexpr string_view rawArt(T);
constexpr auto firstBar = rawArt.find("|");
constexpr auto lastBar = rawArt.find_last_of("|");
constexpr auto art = rawArt.substr(firstBar, lastBar - firstBar);
static_assert(firstBar < lastBar, "ASCII Table has no fields");
// make an array for all of the fields
constexpr auto numFields =
count(rawArt.begin(), rawArt.end(), '|') -
count(rawArt.begin(), rawArt.end(), '\n') / 2;
array<FieldDetails, numFields> fields;
// parse the diagram
bool isValidDiagram = true;
int startDiagramIndex = 0;
int totalBits = 0;
for(int i = 0; i < numFields; )
{
auto beginningBar = art.find("|", startDiagramIndex);
auto endingBar = art.find("|", beginningBar + 1);
auto field = art.substr(beginningBar + 1, endingBar - beginningBar - 1);
if(field.find("-") == field.npos)
{
int numBits = (field.size() + 1) / 3;
auto nameStart = field.find_first_not_of(" ");
auto nameEnd = field.find_last_not_of(" ");
if (nameStart > nameEnd || nameStart == string_view::npos)
{
// the table cannot be parsed
isValidDiagram = false;
field = ""sv;
}
else
{
field = field.substr(nameStart, 1 + nameEnd - nameStart);
}
fields[i++] = FieldDetails {field, numBits};
totalBits += numBits;
}
startDiagramIndex = endingBar;
}
int numRawBytes = isValidDiagram ? (totalBits - 1) / 8 + 1 : 0;
return make_pair(fields, numRawBytes);
}
// encode the values of the fields into a raw data array
template <const char *T> auto Encode(auto inputValues)
{
constexpr auto parsedDiagram = ParseDiagram<T>();
static_assert(parsedDiagram.second > 0, "Invalid ASCII talble");
array<unsigned char, parsedDiagram.second> data;
int startBit = 0;
int i = 0;
for(auto value : inputValues)
{
const auto &field = parsedDiagram.first[i++];
int remainingValueBits = field.NumBits;
while(remainingValueBits > 0)
{
// pack the bits from an input field into the data array
auto [fieldStartByte, fieldStartBit] = div(startBit, 8);
int unusedBits = 8 - fieldStartBit;
int numBitsToEncode = min({unusedBits, 8, field.NumBits});
int divisor = 1 << (remainingValueBits - numBitsToEncode);
unsigned char bitsToEncode = value / divisor;
data[fieldStartByte] <<= numBitsToEncode;
data[fieldStartByte] |= bitsToEncode;
value %= divisor;
startBit += numBitsToEncode;
remainingValueBits -= numBitsToEncode;
}
}
return data;
}
// decode the raw data into the format of the ASCII diagram
template <const char *T> void Decode(auto data)
{
cout << "Name Bit Pattern\n";
cout << "======= ================\n";
constexpr auto parsedDiagram = ParseDiagram<T>();
static_assert(parsedDiagram.second > 0, "Invalid ASCII talble");
int startBit = 0;
for(const auto& field : parsedDiagram.first)
{
// unpack the bits from the data into a single field
auto [fieldStartByte, fieldStartBit] = div(startBit, 8);
unsigned char firstByte = data[fieldStartByte];
firstByte <<= fieldStartBit;
firstByte >>= fieldStartBit;
int64_t value = firstByte;
auto endBit = startBit + field.NumBits;
auto [fieldEndByte, fieldEndBit] = div(endBit, 8);
fieldEndByte = min(fieldEndByte, (int)(ssize(data) - 1));
for(int index = fieldStartByte + 1; index <= fieldEndByte; index++)
{
value <<= 8;
value += data[index];
}
value >>= fieldEndBit;
startBit = endBit;
cout << field.Name <<
string_view(" ", (7 - field.Name.size())) << " " <<
string_view(bitset<64>(value).to_string()).substr(64 - field.NumBits, 64) << "\n";
}
}
int main(void)
{
static constexpr char art[] = R"(
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ID |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|QR| Opcode |AA|TC|RD|RA| Z | RCODE |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| QDCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ANCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| NSCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ARCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+)";
// using the table above, encode the data below
auto rawData = Encode<art> (initializer_list<int64_t> {
30791,
0, 15, 0, 1, 1, 1, 3, 15,
21654,
57646,
7153,
27044
});
cout << "Raw encoded data in hex:\n";
for (auto v : rawData) printf("%.2X", v);
cout << "\n\n";
cout << "Decoded raw data:\n";
Decode<art>(rawData);
}</lang>
{{out}}
<pre>
Raw encoded data in hex:
78477BBF5496E12E1BF169A4
Decoded raw data:
Name Bit Pattern
======= ================
ID 0100011101111011
QR 1
Opcode 0011
AA 0
TC 0
RD 1
RA 1
Z 011
RCODE 0100
QDCOUNT 1001011011100001
ANCOUNT 0010111000011011
NSCOUNT 1111000101101001
ARCOUNT 0110100110100100
</pre>
=={{header|D}}==
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