Files
psopeeps-newserv/src/GSLArchive.cc
T
2025-04-03 10:38:55 -07:00

112 lines
3.3 KiB
C++

#include "GSLArchive.hh"
#include <phosg/Encoding.hh>
#include <phosg/Filesystem.hh>
#include <stdexcept>
#include "Text.hh"
#include "Types.hh"
using namespace std;
template <bool BE>
struct GSLHeaderEntryT {
pstring<TextEncoding::ASCII, 0x20> filename;
U32T<BE> offset; // In pages, so actual offset is this * 0x800
U32T<BE> size;
uint64_t unused;
} __attribute__((packed));
using GSLHeaderEntry = GSLHeaderEntryT<false>;
using GSLHeaderEntryBE = GSLHeaderEntryT<true>;
check_struct_size(GSLHeaderEntry, 0x30);
check_struct_size(GSLHeaderEntryBE, 0x30);
template <bool BE>
void GSLArchive::load_t() {
phosg::StringReader r(*this->data);
uint64_t min_data_offset = 0xFFFFFFFFFFFFFFFF;
while (r.where() < min_data_offset) {
const auto& entry = r.get<GSLHeaderEntryT<BE>>();
if (entry.filename.empty()) {
break;
}
uint64_t offset = static_cast<uint64_t>(entry.offset) * 0x800;
if (offset + entry.size > this->data->size()) {
throw runtime_error("GSL entry extends beyond end of data");
}
this->entries.emplace(entry.filename.decode(), Entry{offset, entry.size});
}
}
GSLArchive::GSLArchive(shared_ptr<const string> data, bool big_endian)
: data(data) {
if (big_endian) {
this->load_t<true>();
} else {
this->load_t<false>();
}
}
const unordered_map<string, GSLArchive::Entry> GSLArchive::all_entries() const {
return this->entries;
}
pair<const void*, size_t> GSLArchive::get(const std::string& name) const {
try {
const auto& entry = this->entries.at(name);
return make_pair(this->data->data() + entry.offset, entry.size);
} catch (const out_of_range&) {
throw out_of_range("GSL does not contain file: " + name);
}
}
string GSLArchive::get_copy(const string& name) const {
try {
const auto& entry = this->entries.at(name);
return this->data->substr(entry.offset, entry.size);
} catch (const out_of_range&) {
throw out_of_range("GSL does not contain file: " + name);
}
}
phosg::StringReader GSLArchive::get_reader(const string& name) const {
try {
const auto& entry = this->entries.at(name);
return phosg::StringReader(this->data->data() + entry.offset, entry.size);
} catch (const out_of_range&) {
throw out_of_range("GSL does not contain file: " + name);
}
}
string GSLArchive::generate(const unordered_map<string, string>& files, bool big_endian) {
return big_endian ? GSLArchive::generate_t<true>(files) : GSLArchive::generate_t<false>(files);
}
template <bool BE>
string GSLArchive::generate_t(const unordered_map<string, string>& files) {
phosg::StringWriter w;
// Make sure there's enough space for a blank header entry before any file's
// data pages begin
uint32_t data_start_offset = ((sizeof(GSLHeaderEntryT<BE>) * (files.size() + 1)) + 0x7FF) & (~0x7FF);
uint32_t data_offset = data_start_offset;
for (const auto& file : files) {
GSLHeaderEntryT<BE> entry;
entry.filename.encode(file.first);
entry.offset = data_offset >> 11;
entry.size = file.second.size();
entry.unused = 0;
w.put(entry);
data_offset = (data_offset + file.second.size() + 0x7FF) & (~0x7FF);
}
w.extend_to(data_start_offset);
for (const auto& file : files) {
w.write(file.second);
w.extend_to((w.size() + 0x7FF) & (~0x7FF));
}
return std::move(w.str());
}