OXYGENHUB
◆ main openmsx / src / memory / Ram.cc
2.9 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
e8555c89 Andy McCall 1 
#include "Ram.hh"
2
3 
#include "DeviceConfig.hh"
4 
#include "MSXException.hh"
5 
#include "XMLElement.hh"
6
7 
#include "Base64.hh"
8 
#include "HexDump.hh"
9 
#include "narrow.hh"
10 
#include "one_of.hh"
11 
#include "serialize.hh"
12
13 
#include <zlib.h>
14
15 
#include <algorithm>
16 
#include <bit>
17
18 
namespace openmsx {
19
20 
Ram::Ram(const DeviceConfig& config, const std::string& name,
21 
         static_string_view description, size_t size, bool* debugWrite)
22 
	: xml(*config.getXML())
23 
	, ram(size)
24 
	, debuggable(std::in_place,
25 
		config.getMotherBoard(), name, description, *this, debugWrite ? debugWrite : &dummyDebugWrite)
26 
{
27 
	clear();
28 
}
29
30 
Ram::Ram(const XMLElement& xml_, size_t size)
31 
	: xml(xml_)
32 
	, ram(size)
33 
{
34 
	clear();
35 
}
36
37 
void Ram::clear(uint8_t c)
38 
{
39 
	if (const auto* init = xml.findChild("initialContent")) {
40 
		// get pattern (and decode)
41 
		auto encoding = init->getAttributeValue("encoding");
42 
		size_t done = 0;
43 
		if (encoding == "gz-base64") {
44 
			auto buf = Base64::decode(init->getData());
45 
			auto dstLen = narrow<uLongf>(size());
46 
			if (uncompress(std::bit_cast<Bytef*>(ram.data()), &dstLen,
47 
			               std::bit_cast<const Bytef*>(buf.data()), uLong(buf.size()))
48 
			     != Z_OK) {
49 
				throw MSXException("Error while decompressing initialContent.");
50 
			}
51 
			done = dstLen;
52 
		} else if (encoding == one_of("hex", "base64")) {
53 
			auto buf = (encoding == "hex")
54 
			       ? HexDump::decode(init->getData())
55 
			       : Base64 ::decode(init->getData());
56 
			if (buf.empty()) {
57 
				throw MSXException("Zero-length initial pattern");
58 
			}
59 
			done = std::min(size(), buf.size());
60 
			copy_to_range(buf.first(done), ram);
61 
		} else {
62 
			throw MSXException("Unsupported encoding \"", encoding,
63 
			                   "\" for initialContent");
64 
		}
65
66 
		// repeat pattern over whole ram
67 
		auto left = size() - done;
68 
		while (left) {
69 
			auto tmp = std::min(done, left);
70 
			copy_to_range(std::span{ram.data(), tmp}, subspan(ram, done));
71 
			done += tmp;
72 
			left -= tmp;
73 
		}
74 
	} else {
75 
		// no init pattern specified
76 
		std::ranges::fill(*this, c);
77 
	}
78 
}
79
80 
const std::string& Ram::getName() const
81 
{
82 
	assert(debuggable);
83 
	return debuggable->getName();
84 
}
85
86 
RamDebuggable::RamDebuggable(MSXMotherBoard& motherBoard_,
87 
                             const std::string& name_,
88 
                             static_string_view description_, Ram& ram_, bool* debugWrite_)
89 
	: SimpleDebuggable(motherBoard_, name_, description_, narrow<unsigned>(ram_.size()))
90 
	, ram(ram_)
91 
	, debugWrite(debugWrite_)
92 
{
93 
}
94
95 
uint8_t RamDebuggable::read(unsigned address)
96 
{
97 
	return ram[address];
98 
}
99
100 
void RamDebuggable::readBlock(unsigned start, std::span<uint8_t> output)
101 
{
102 
	copy_to_range(std::span{ram}.subspan(start, output.size()), output);
103 
}
104
105 
void RamDebuggable::write(unsigned address, uint8_t value)
106 
{
107 
	ram[address] = value;
108 
	*debugWrite = true; // for TrackedRam
109 
}
110
111
112 
template<typename Archive>
113 
void Ram::serialize(Archive& ar, unsigned /*version*/)
114 
{
115 
	ar.serialize_blob("ram", std::span{*this});
116 
}
117 
INSTANTIATE_SERIALIZE_METHODS(Ram);
118
119 
} // namespace openmsx