ips_layer: Add support for escape sequences and midline comments

More accurately follows IPSwitch specification.
master
Zach Hilman 2018-10-01 08:31:34 +07:00
parent 8886f2e55e
commit 9669cdb710
3 changed files with 41 additions and 8 deletions

@ -17,6 +17,11 @@ enum class IPSFileType {
Error,
};
const std::map<const char*, const char*> ESCAPE_CHARACTER_MAP{
{"\\a", "\a"}, {"\\b", "\b"}, {"\\f", "\f"}, {"\\n", "\n"}, {"\\r", "\r"}, {"\\t", "\t"},
{"\\v", "\v"}, {"\\\\", "\\"}, {"\\\'", "\'"}, {"\\\"", "\""}, {"\\\?", "\?"},
};
static IPSFileType IdentifyMagic(const std::vector<u8>& magic) {
if (magic.size() != 5)
return IPSFileType::Error;
@ -89,7 +94,7 @@ VirtualFile PatchIPS(const VirtualFile& in, const VirtualFile& ips) {
IPSwitchCompiler::IPSwitchCompiler(VirtualFile patch_text_)
: valid(false), patch_text(std::move(patch_text_)), nso_build_id{}, is_little_endian(false),
offset_shift(0), print_values(false) {
offset_shift(0), print_values(false), last_comment("") {
Parse();
}
@ -105,6 +110,18 @@ static bool StartsWith(const std::string& base, const std::string& check) {
return base.size() >= check.size() && base.substr(0, check.size()) == check;
}
static std::string EscapeStringSequences(std::string in) {
for (const auto& seq : ESCAPE_CHARACTER_MAP) {
for (auto index = in.find(seq.first); index != std::string::npos;
index = in.find(seq.first, index)) {
in.replace(index, std::strlen(seq.first), seq.second);
index += std::strlen(seq.second);
}
}
return in;
}
void IPSwitchCompiler::Parse() {
const auto bytes = patch_text->ReadAllBytes();
std::stringstream s;
@ -121,6 +138,13 @@ void IPSwitchCompiler::Parse() {
for (std::size_t i = 0; i < lines.size(); ++i) {
auto line = lines[i];
// Remove midline comments
if (!StartsWith(line, "//") && line.find("//") != std::string::npos) {
last_comment = line.substr(line.find("//") + 2);
line = line.substr(0, line.find("//"));
}
if (StartsWith(line, "@stop")) {
// Force stop
break;
@ -132,11 +156,18 @@ void IPSwitchCompiler::Parse() {
nso_build_id = Common::HexStringToArray<0x20>(raw_build_id);
} else if (StartsWith(line, "@flag offset_shift ")) {
// Offset Shift Flag
offset_shift = std::stoull(line.substr(19), nullptr, 0);
offset_shift = std::stoll(line.substr(19), nullptr, 0);
} else if (StartsWith(line, "#")) {
// Mandatory Comment
LOG_INFO(Loader, "[IPSwitchCompiler ('{}')] Forced output comment: {}",
patch_text->GetName(), line.substr(1));
} else if (StartsWith(line, "//")) {
// Normal Comment
last_comment = line.substr(2);
if (last_comment.find_first_not_of(' ') == std::string::npos)
continue;
if (last_comment.find_first_not_of(' ') != 0)
last_comment = last_comment.substr(last_comment.find_first_not_of(' '));
} else if (StartsWith(line, "@little-endian")) {
// Set values to read as little endian
is_little_endian = true;
@ -151,11 +182,10 @@ void IPSwitchCompiler::Parse() {
const auto enabled = StartsWith(line, "@enabled");
if (i == 0)
return;
const auto name = lines[i - 1].substr(3);
LOG_INFO(Loader, "[IPSwitchCompiler ('{}')] Parsing patch '{}' ({})",
patch_text->GetName(), name, line.substr(1));
patch_text->GetName(), last_comment, line.substr(1));
IPSwitchPatch patch{name, enabled, {}};
IPSwitchPatch patch{last_comment, enabled, {}};
// Read rest of patch
while (true) {
@ -173,10 +203,11 @@ void IPSwitchCompiler::Parse() {
// 9 - first char of replacement val
if (line[9] == '\"') {
// string replacement
const auto end_index = line.find_last_of('\"');
const auto end_index = line.find('\"', 10);
if (end_index == std::string::npos || end_index < 10)
return;
const auto value = line.substr(10, end_index - 10);
auto value = line.substr(10, end_index - 10);
value = EscapeStringSequences(value);
replace.reserve(value.size());
std::copy(value.begin(), value.end(), std::back_inserter(replace));
} else {

@ -34,8 +34,9 @@ private:
std::vector<IPSwitchPatch> patches;
std::array<u8, 0x20> nso_build_id;
bool is_little_endian;
u64 offset_shift;
s64 offset_shift;
bool print_values;
std::string last_comment;
};
} // namespace FileSys

@ -36,6 +36,7 @@ public:
// Currently tracked NSO patches:
// - IPS
// - IPSwitch
std::vector<u8> PatchNSO(const std::vector<u8>& nso) const;
// Checks to see if PatchNSO() will have any effect given the NSO's build ID.