parse root version

src/app_state.h

@@ -10,7 +10,7 @@ struct Inspected_File {
   u8   *mem;
   u64   size;
 
-  const char *name;
+  String8 name;
 
 	// @Platform: inotify file descriptor
   int inot;
@@ -20,10 +20,11 @@ struct App_State {
   Window_Data win_data;
   User_Input user_input;
   RNTuple_Data rndata;
+  TFile_Data tfile_data;
   Viewer viewer;
   Inspected_File inspected_file;
 
-	const char *ntpl_name;
+	String8 ntpl_name;
 
   Delta_Time_Accum delta_time_accum;
 

src/platform_linux.h

@@ -25,7 +25,7 @@ bool os_open_and_map_file(const char *fname, App_State &app)
   if (!fmem)
     fprintf(stderr, "Failed to open file %s\n", fname);
 
-  app.inspected_file.name = fname;
+  app.inspected_file.name = str8(fname);
   app.inspected_file.stream = file;
   app.inspected_file.size = fsize;
   app.inspected_file.mem = reinterpret_cast<u8*>(fmem);

src/render.cpp

@@ -35,13 +35,15 @@ u32 mem_edit_bg_color_fn(const u8 *, u64 off, void *user_data)
 {
   App_State *app = reinterpret_cast<App_State *>(user_data);
   const RNTuple_Data &rdata = app->rndata;
+  const TFile_Data &tdata = app->tfile_data;
   u64 rblob_sz = rdata.rblob_header_size; // @Incomplete
 
   off += app->viewer.base_display_addr;
 
 #define COL(c) (ImColor((c)[0], (c)[1], (c)[2]))
   // TFile start
-  if (off <= rdata.root_file_header_size) return COL(app->viewer.col_tfile);
+  if (off <= tdata.root_file_header_size) return COL(app->viewer.col_tfile_header);
+  if (tdata.rng_root_file_obj.start <= off && off < tdata.rng_root_file_obj.end()) return COL(app->viewer.col_tfile_obj);
 
   // Handle pages
   // fast case: `off` is in the same page info as previous `off`.
@@ -135,7 +137,8 @@ void make_viewer(App_State &app)
   COL(col_header, 150, 0, 50);
   COL(col_footer, 50, 0, 150);
   COL(col_key,    0, 100, 50);
-  COL(col_tfile,  90, 90, 90);
+  COL(col_tfile_header,  90, 90, 90);
+  COL(col_tfile_obj,  120, 120, 120);
   COL(col_page,   125, 0, 125);
   COL(col_page_start, 200, 0, 200);
   COL(col_checksum, 134, 65, 25);
@@ -184,7 +187,7 @@ void update_and_render(Arena *arena, App_State &app, f32 delta_time_ms)
   if (ImGui::Begin("main", nullptr, main_win_flags)) {
         
     String8 ntpl_desc = rntuple_description(scratch.arena, app.rndata);
-    ImGui::Text("RNTuple '%s' (%s) from file \"%s\"", app.ntpl_name, ntpl_desc.c(), app.inspected_file.name);
+    ImGui::Text("RNTuple '%s' (%s) from file \"%s\"", app.ntpl_name.c(), ntpl_desc.c(), app.inspected_file.name.c());
 
     // Draw stats
     {
@@ -222,9 +225,13 @@ void update_and_render(Arena *arena, App_State &app, f32 delta_time_ms)
       ImGui::TableNextColumn();
       ImGuiColorEditFlags flags =  ImGuiColorEditFlags_NoInputs|ImGuiColorEditFlags_NoLabel;
 
-      ImGui::ColorEdit3("_TFile",          app.viewer.col_tfile,  flags);
+      ImGui::ColorEdit3("_TFile Header",   app.viewer.col_tfile_header,  flags);
       ImGui::SameLine(); 
-      if (ImGui::Button("TFile"))          viewer_jump_to(app.viewer, 0);
+      if (ImGui::Button("TFile Header"))   viewer_jump_to(app.viewer, 0);
+
+      ImGui::ColorEdit3("_TFile Object",   app.viewer.col_tfile_obj,  flags);
+      ImGui::SameLine(); 
+      if (ImGui::Button("TFile Object"))   viewer_jump_to(app.viewer, app.tfile_data.rng_root_file_obj.start);
 
       ImGui::ColorEdit3("_RNTuple Anchor", app.viewer.col_anchor, flags);
       ImGui::SameLine(); 
@@ -278,6 +285,11 @@ void update_and_render(Arena *arena, App_State &app, f32 delta_time_ms)
       ImGui::Text("%s", to_pretty_size(scratch.arena, app.rndata.tot_page_list_size).c());
 
       ImGui::Separator();
+      String8 root_version_str = push_str8f(scratch.arena, "%u.%u.%u", 
+                                            app.tfile_data.root_version_major,
+                                            app.tfile_data.root_version_minor,
+                                            app.tfile_data.root_version_patch);
+      ImGui::Text("ROOT version: %s", root_version_str.c());
       ImGui::Text("Num pages: %lu", app.rndata.n_pages);
       ImGui::Text("Num elements: %lu", app.rndata.n_elems);
 

src/render.h

@@ -5,7 +5,8 @@ struct Viewer {
   f32 col_header[3];
   f32 col_footer[3];
   f32 col_key[3];
-  f32 col_tfile[3];
+  f32 col_tfile_header[3];
+  f32 col_tfile_obj[3];
   f32 col_page[3];
   f32 col_page_start[3];
   f32 col_checksum[3];

src/rntuple.cpp

@@ -63,7 +63,7 @@ ROOT::Experimental::RNTupleDescriptor create_descriptor(Arena *arena, RMicroFile
 }
 
 internal
-void gather_metadata(Arena *arena, RMicroFileReader &reader, const RNTuple_File_Info &info, RNTuple_Data &rndata)
+void gather_ntuple_metadata(Arena *arena, RMicroFileReader &reader, const RNTuple_File_Info &info, RNTuple_Data &rndata)
 {
   using namespace ROOT::Experimental;
   using namespace ROOT::Experimental::Internal;
@@ -230,13 +230,39 @@ void gather_metadata(Arena *arena, RMicroFileReader &reader, const RNTuple_File_
 }
 
 internal
-RNTuple_Data get_rntuple_data(Arena *arena, const char *fname, const char *ntpl_name)
+TFile_Data get_tfile_data(const Inspected_File &file)
+{ 
+  TFile_Data tfile_data{};
+  
+  Root_File_Info root_file_info = get_root_file_info(file.name.c());
+  tfile_data.root_file_header_size = root_file_info.tfile_header_nbytes;
+  tfile_data.rng_root_file_obj.start = root_file_info.tfile_obj_seek;
+  tfile_data.rng_root_file_obj.len = root_file_info.tfile_obj_nbytes;
+
+  // parse root version
+  const u64 len_root_magic = 4;
+  assert(file.size > len_root_magic + sizeof(u32));
+  u32 version_be;  
+  memcpy(&version_be, file.mem + len_root_magic, sizeof(version_be));
+  u32 version = bswap_32(version_be);
+  u32 version_major = version / 10000;
+  u32 version_minor = (version - version_major * 10000) / 100;
+  u32 version_patch = (version - version_major * 10000 - version_minor * 100);
+  tfile_data.root_version_major = (u16)version_major;
+  tfile_data.root_version_minor = (u16)version_minor;
+  tfile_data.root_version_patch = (u16)version_patch;
+  
+  return tfile_data;
+}
+
+internal
+RNTuple_Data get_rntuple_data(Arena *arena, const Inspected_File &file, String8 ntpl_name)
 {
-  RNTuple_Data rndata = {};
+  RNTuple_Data rndata {};
   
   // TODO: proper error handling
-  RMicroFileReader file_reader { fname };
+  RMicroFileReader file_reader { file.name.c() };
-  RNTuple_File_Info file_info = file_reader.GetNTupleProper(ntpl_name);
+  RNTuple_File_Info file_info = file_reader.GetNTupleProper(ntpl_name.c());
   if (!file_info.failed) {
     rndata.version.epoch = file_info.anchor.fVersionEpoch;
     rndata.version.major = file_info.anchor.fVersionMajor;
@@ -251,9 +277,8 @@ RNTuple_Data get_rntuple_data(Arena *arena, const char *fname, const char *ntpl_
     rndata.rng_anchor_key.start = file_info.anchor_key_seek;
     rndata.rng_anchor_key.len = file_info.anchor_key_nbytes;
     rndata.rblob_header_size = file_info.rblob_key_header_nbytes;
-    rndata.root_file_header_size = file_info.tfile_header_nbytes;
 
-    gather_metadata(arena, file_reader, file_info, rndata);
+    gather_ntuple_metadata(arena, file_reader, file_info, rndata);
   }
 
   return rndata;

src/rntuple.h

@@ -37,12 +37,19 @@ struct Cluster_Group_Info {
   Byte_Range rng_page_list;
 };
 
+struct TFile_Data {
+  u64 root_file_header_size;
+  Byte_Range rng_root_file_obj;
+  u16 root_version_major;
+  u16 root_version_minor;
+  u16 root_version_patch;
+};
+
 struct RNTuple_Data {
   struct {
     u16 epoch, major, minor, patch;
   } version;
   
-  u64 root_file_header_size;
   u64 rblob_header_size;
   Byte_Range rng_anchor;
   Byte_Range rng_anchor_key;

src/rntviewer.cpp

@@ -13,6 +13,7 @@
 
 #include <cstdio>
 #include <cstdint>
+#include <byteswap.h>
 #include <utility>    // for std::forward
 #include <chrono>
 
@@ -124,8 +125,9 @@ int main(int argc, char **argv)
     os_start_file_watch(fname, app);
   }
 
-  app.ntpl_name = ntpl_name;
+  app.ntpl_name = str8(ntpl_name);
-  app.rndata = get_rntuple_data(arena, fname, ntpl_name);
+  app.tfile_data = get_tfile_data(app.inspected_file);
+  app.rndata = get_rntuple_data(arena, app.inspected_file, app.ntpl_name);
   make_viewer(app);
   
   // Start main loop

src/root/RMicroFileReader.cxx

@@ -1068,17 +1068,29 @@ static size_t ComputeNumChunks(size_t nbytes, size_t maxChunkSize)
 //                         PUBLIC INTERFACE
 // =========================================================================================
 
+Root_File_Info get_root_file_info(const char *fname)
+{
+   RTFString fileName { fname };
+   Root_File_Info fileInfo {};
+   fileInfo.tfile_header_nbytes = RTFHeader{}.GetSize();
+   fileInfo.tfile_obj_seek = 100; // kBEGIN
+   fileInfo.tfile_obj_nbytes = sizeof(RTFFile) + fileName.GetSize() + RTFString{}.GetSize() + RTFUUID{}.GetSize();
+   return fileInfo;
+}
+
 struct RMicroFileReader::Impl {
   std::unique_ptr<ROOT::Internal::RRawFile> fRawFile;
   std::uint64_t fMaxBlobSize = 0;
 };
 
-RMicroFileReader::RMicroFileReader(const char *fname) {
+RMicroFileReader::RMicroFileReader(const char *fname)
+{
    impl = new Impl;
    impl->fRawFile = ROOT::Internal::RRawFile::Create(fname);
 }
 
-RMicroFileReader::~RMicroFileReader() {
+RMicroFileReader::~RMicroFileReader()
+{
    delete impl;
 }
 
@@ -1183,7 +1195,6 @@ RMicroFileReader::GetNTupleProper(const char *ntupleName)
       dummy.MakeBigKey();
       fileInfo.rblob_key_header_nbytes = dummy.GetHeaderSize();
    }
-   fileInfo.tfile_header_nbytes = RTFHeader{}.GetSize();
    // @----
    ReadBuffer(ntuple, objNbytes, offset);
    if (objNbytes != key.fObjLen) {

src/root/RMicroFileReader.hxx

@@ -38,9 +38,16 @@ struct RNTuple_File_Info {
   std::uint64_t anchor_key_seek;
   std::uint64_t anchor_key_nbytes;
   std::uint64_t rblob_key_header_nbytes;
-  std::uint64_t tfile_header_nbytes;
 };
 
+struct Root_File_Info {
+  std::uint64_t tfile_header_nbytes;
+  std::uint64_t tfile_obj_seek;
+  std::uint64_t tfile_obj_nbytes;
+};
+
+Root_File_Info get_root_file_info(const char *fname);
+
 class RMicroFileReader final {
 public:
   explicit RMicroFileReader(const char *fname);

src/str.h

@@ -5,6 +5,6 @@ struct String8 {
   const char *c() const { return reinterpret_cast<const char *>(str); }
 };
 
-#define str8(s) String8((u8*)(s), sizeof(s) - 1)
+#define str8(s) String8 { (u8*)(s), sizeof(s) - 1 }
 
 String8 push_str8f(Arena *arena, char *fmt, ...);