VFS perf fixes, icon/stylesheet compat, download filename fix

VFS:
- Open backing fd at mo2_open time for read-only handles so mo2_read can
  splice without re-opening the file on every read call.
- Bump RLIMIT_NOFILE at mount time to fit the resulting fd pressure when
  the game keeps hundreds of BSAs open.
- Dedicated node_cache_mutex so resolveByInode / mo2_lookup stop racing
  unordered_map writes while multiple tree_mutex readers are active.
- max_read=1MB + matching conn->max_read and raised max_readahead/max_write
  so the kernel merges Wine's small sequential reads into bigger FUSE
  requests.
- Per-op wall-clock counters in mo2_init() logs so we can distinguish VFS
  latency from game-side work.

Proton launch:
- Write dxvk.conf to the prefix and set DXVK_CONFIG_FILE to force
  dxvk.enableGraphicsPipelineLibrary=False, avoiding long GPL compile
  stalls on first run.

UI / plugin compat:
- Clamp IconDelegate's per-icon width to [8, 16] so narrow content
  columns don't trigger QIcon::pixmap(0,0) returning null and logging
  "failed to load icon" every repaint.
- Pre-create lowercase symlinks in the stylesheet directory so QSS files
  authored on Windows resolve url(foo.svg) when on-disk files are Foo.svg.
- Flip content icons empty-chessboard.png and facegen.png to 8-bit RGBA
  so Qt's built-in PNG reader loads them uniformly.
- Add mobase.Version.canonicalString shim for legacy Python plugins that
  still call the old VersionInfo method on appVersion()'s return.
- BSPluginList: compare normalized plugin name lists instead of byte
  hashes so the post-run case-fix refresh stops spuriously firing the
  "load order changed" dialog.
- BSPluginList disabled by default.

Download manager:
- Parse CDN URL with QUrl + QUrlQuery and read the filename from the
  response-content-disposition query param (RFC 6266 quoted / unquoted /
  ext-value forms), not QFileInfo on the raw URL.
- When the API or URL gives us a CDN object key (no archive extension),
  prefer the actual Content-Disposition header from the live response in
  metaDataChanged and downloadFinished.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 238 insertions, 0 deletions

diff --git a/libs/installer_bsplugins/src/TESFile/Reader.inl b/libs/installer_bsplugins/src/TESFile/Reader.inl
new file mode 100644
index 0000000..3324a15
--- /dev/null
+++ b/libs/installer_bsplugins/src/TESFile/Reader.inl
@@ -0,0 +1,238 @@
+#include "Reader.h"
+
+#include <zlib.h>
+
+#include <cstring>
+#include <format>
+#include <fstream>
+#include <stdexcept>
+
+namespace TESFile
+{
+
+template <ReaderHandler Handler>
+inline void Reader<Handler>::parse(const std::filesystem::path& path, Handler& handler)
+{
+  std::ifstream stream;
+  stream.open(path, std::ios_base::binary | std::ios_base::in);
+  if (!stream.good()) {
+    throw std::runtime_error(std::strerror(errno));
+  }
+  parse(stream, handler);
+}
+
+template <ReaderHandler Handler>
+inline void Reader<Handler>::parse(std::istream& stream, Handler& handler)
+{
+  parsePluginInfo(stream, handler);
+  while (stream.good() && stream.peek() != std::char_traits<char>::eof()) {
+    parseRecord(stream, handler);
+  }
+}
+
+template <ReaderHandler Handler>
+inline std::uint32_t Reader<Handler>::parsePluginInfo(std::istream& stream,
+                                                      Handler& handler)
+{
+  const RecordHeader header = readType<RecordHeader>(stream);
+  if (stream.fail()) {
+    throw std::runtime_error("record incomplete");
+  }
+
+  if (header.type == "TES4"_ts) {
+    if (header.old.firstChunk == "HEDR"_ts) {
+      chunkFormat_ = TESFormat::Oblivion;
+      headerSize_  = HeaderSize_Oblivion;
+      stream.seekg(HeaderSize_Oblivion - sizeof(RecordHeader), std::istream::cur);
+    } else {
+      chunkFormat_ = TESFormat::Standard;
+      headerSize_  = sizeof(RecordHeader);
+    }
+  } else if (header.type == "TES3"_ts) {
+    chunkFormat_ = TESFormat::Morrowind;
+    headerSize_  = HeaderSize_Morrowind;
+    stream.seekg(HeaderSize_Morrowind - sizeof(RecordHeader), std::istream::cur);
+  } else {
+    throw std::runtime_error(
+        std::format("Unrecognized plugin info type: '{}'", header.type.value));
+  }
+
+  return handleForm(stream, header, handler);
+}
+
+template <ReaderHandler Handler>
+inline std::uint32_t Reader<Handler>::parseRecord(std::istream& stream,
+                                                  Handler& handler)
+{
+  RecordHeader header;
+  stream.read(reinterpret_cast<char*>(&header), headerSize_);
+  if (stream.fail()) {
+    throw std::runtime_error("record incomplete");
+  }
+
+  if (header.type == "GRUP"_ts) {
+    return handleGroup(stream, header, handler);
+  } else {
+    return handleForm(stream, header, handler);
+  }
+}
+
+template <ReaderHandler Handler>
+inline std::uint32_t Reader<Handler>::handleForm(std::istream& stream,
+                                                 const RecordHeader& header,
+                                                 Handler& handler)
+{
+  std::uint32_t dataSize = header.dataSize;
+  const bool compressed  = header.formData.flags & RecordFlags::Compressed;
+  // Check for Oblivion plugin data
+  uint16_t version       = 0;
+  if (header.old.firstChunk.string() != "HEDR") {
+    version = header.version;
+  }
+  if (handler.Form(
+          FormData(header.type, header.formData.flags, header.formData.formId, version))) {
+
+    std::string data;
+    data.resize(dataSize);
+    stream.read(data.data(), dataSize);
+    if (stream.fail()) {
+      throw std::runtime_error("chunk incomplete");
+    }
+
+    std::istringstream chunkstream;
+    if (!compressed) {
+      chunkstream.str(std::move(data));
+    } else {
+      if (data.size() < 4) {
+        throw std::runtime_error("chunk incomplete");
+      }
+
+      std::memcpy(&dataSize, data.data(), sizeof(dataSize));
+
+      std::string inflated;
+      inflated.resize(dataSize);
+
+      int zret;
+      ::z_stream zstreambuf{
+          .next_in = reinterpret_cast<z_const ::Bytef*>(data.data() + sizeof(dataSize)),
+          .avail_in  = static_cast<::uInt>(data.size() - sizeof(dataSize)),
+          .next_out  = reinterpret_cast<::Bytef*>(inflated.data()),
+          .avail_out = static_cast<::uInt>(inflated.size()),
+          .zalloc    = Z_NULL,
+          .zfree     = Z_NULL,
+          .opaque    = Z_NULL,
+      };
+      zret = ::inflateInit(&zstreambuf);
+      if (zret != Z_OK) {
+        throw std::runtime_error("zlib failed to init");
+      }
+
+      zret = ::inflate(&zstreambuf, Z_FINISH);
+      if (zret != Z_STREAM_END) {
+        throw std::runtime_error("zlib failed to read data");
+      }
+      zret = ::inflateEnd(&zstreambuf);
+
+      chunkstream.str(std::move(inflated));
+    }
+
+    while (dataSize != 0) {
+      const std::uint32_t fieldSize = parseChunk(chunkstream, handler);
+
+      if (fieldSize > dataSize) {
+        throw std::runtime_error(
+            std::format("Subrecord exceeded record size ({}-{})", dataSize, fieldSize));
+      }
+
+      dataSize -= fieldSize;
+    }
+
+    if constexpr (requires { handler.EndForm(); }) {
+      handler.EndForm();
+    }
+  } else {
+    stream.seekg(dataSize, std::istream::cur);
+    if (stream.fail()) {
+      throw std::runtime_error("record incomplete");
+    }
+  }
+
+  return headerSize_ + header.dataSize;
+}
+
+template <ReaderHandler Handler>
+inline std::uint32_t Reader<Handler>::handleGroup(std::istream& stream,
+                                                  const RecordHeader& header,
+                                                  Handler& handler)
+{
+  std::uint32_t dataSize = header.dataSize - headerSize_;
+
+  if (handler.Group(GroupData(header.groupData.label, header.groupData.groupType))) {
+
+    while (dataSize != 0) {
+      const std::uint32_t recordSize = parseRecord(stream, handler);
+
+      if (recordSize > dataSize) {
+        throw std::runtime_error(
+            std::format("Record exceeded group size ({}-{})", dataSize, recordSize));
+      }
+
+      dataSize -= recordSize;
+    }
+
+    if constexpr (requires { handler.EndGroup(); }) {
+      handler.EndGroup();
+    }
+  } else {
+    stream.seekg(dataSize, std::istream::cur);
+    if (stream.fail()) {
+      throw std::runtime_error("group incomplete");
+    }
+  }
+
+  return header.dataSize;
+}
+
+template <ReaderHandler Handler>
+inline std::uint32_t Reader<Handler>::parseChunk(std::istream& stream, Handler& handler)
+{
+  ChunkHeader header = readType<ChunkHeader>(stream);
+  if (stream.fail()) {
+    throw std::runtime_error("chunk header incomplete");
+  }
+  std::uint32_t readSize = sizeof(ChunkHeader) + header.dataSize;
+
+  std::uint32_t dataSize = header.dataSize;
+  if (header.type == "XXXX"_ts) {
+    if (dataSize != 4) {
+      throw std::runtime_error("XXXX field has invalid size");
+    }
+    dataSize = readType<std::uint32_t>(stream);
+    header   = readType<ChunkHeader>(stream);
+    if (stream.fail()) {
+      throw std::runtime_error("chunk size incomplete");
+    }
+    readSize += sizeof(ChunkHeader) + dataSize;
+  }
+
+  if (handler.Chunk(header.type)) {
+    std::string field;
+    field.resize(dataSize);
+    stream.read(field.data(), dataSize);
+    if (stream.fail()) {
+      throw std::runtime_error("chunk data incomplete");
+    }
+    std::istringstream data(std::move(field));
+    data.exceptions(std::ios_base::failbit);
+    handler.Data(data);
+  } else {
+    stream.seekg(dataSize, std::istream::cur);
+    if (stream.fail()) {
+      throw std::runtime_error("chunk incomplete");
+    }
+  }
+
+  return readSize;
+}
+
+}  // namespace TESFile