add PseudoMiniFile

Makefile

@@ -3,20 +3,23 @@ CFLAGS = -Wall -Wextra -pedantic
 INC = -Ithird_party -Ithird_party/imgui
 ROOT = $(HOME)/root_build/debug
 ROOTFLAGS = -std=c++17 -m64 -I$(ROOT)/include
-ROOTLIBS = -L$(ROOT)/lib -lCore -lRIO -lROOTNTuple -Wl,-rpath,$(ROOT)/lib -pthread
+ROOTLIBS = -L$(ROOT)/lib -lCore -lRIO -lROOTNTuple -lxxhash -Wl,-rpath,$(ROOT)/lib -pthread 
 LIBS = -lglfw
 MOLD = mold -run
 
-all: build/imgui.o d
+all: build/imgui.o build/root_stuff.o noasan
 
 build/imgui.o: src/imgui_inc.cpp third_party/imgui/imgui.h
 	$(CXX) -O3 -fPIC -c -Ithird_party/imgui $< -o $@
+
+build/root_stuff.o: src/PseudoMiniFile.cxx
+	$(CXX) -fPIC -c $(ROOTFLAGS) $< -o $@
 	
 d:
-	$(MOLD) $(CXX) -DDEBUG -g -O0 -DENABLE_ASAN $(CFLAGS) -fsanitize=undefined $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o -lasan $(ROOTLIBS) $(LIBS)
+	$(MOLD) $(CXX) -DDEBUG -g -O0 -DENABLE_ASAN $(CFLAGS) -fsanitize=undefined $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o build/root_stuff.o -lasan $(ROOTLIBS) $(LIBS)
 
 noasan:
-	$(MOLD) $(CXX) -DDEBUG -g -O0 $(CFLAGS) -fsanitize=undefined $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o $(ROOTLIBS) $(LIBS)
+	$(MOLD) $(CXX) -DDEBUG -g -O0 $(CFLAGS) -fsanitize=undefined $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o build/root_stuff.o $(ROOTLIBS) $(LIBS)
 
 r:
-	$(MOLD) $(CXX) -O2 $(CFLAGS) $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o $(ROOTLIBS) $(LIBS)
+	$(MOLD) $(CXX) -O2 $(CFLAGS) $(INC) $(ROOTFLAGS) -o rntviewer src/rntviewer.cpp build/imgui.o build/root_stuff.o $(ROOTLIBS) $(LIBS)

imgui.ini

@@ -8,7 +8,7 @@ Size=1152,1414
 
 [Window][main]
 Pos=0,0
-Size=1183,680
+Size=1777,680
 
 [Window][Hex View]
 Pos=91,62

src/PseudoMiniFile.hxx

@@ -0,0 +1,41 @@
+#pragma once
+
+#include <ROOT/RError.hxx>
+#include <ROOT/RNTuple.hxx>
+#include <ROOT/RRawFile.hxx>
+#include <string_view>
+
+#include <cstdint>
+#include <cstdio>
+#include <memory>
+#include <string>
+
+struct RNTuple_FileInfo {
+  std::uint64_t anchor_seek;
+  std::uint64_t anchor_nbytes;
+  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;
+};
+
+class PseudoMiniFileReader final {
+public:
+  explicit PseudoMiniFileReader(ROOT::Internal::RRawFile *rawFile);
+
+  // ROOT::Experimental::RResult<ROOT::Experimental::RNTuple> 
+  ROOT::Experimental::RResult<RNTuple_FileInfo>
+  GetNTupleProper(std::string_view ntupleName);
+
+  void
+  ReadBuffer(void *buffer, size_t nbytes, std::uint64_t offset);
+
+  // ROOT::Experimental::RNTuple
+  // CreateAnchor(
+  //  std::uint16_t versionEpoch, std::uint16_t versionMajor, std::uint16_t versionMinor, std::uint16_t versionPatch,
+  //  std::uint64_t seekHeader, std::uint64_t nbytesHeader, std::uint64_t lenHeader, std::uint64_t seekFooter,
+  //  std::uint64_t nbytesFooter, std::uint64_t lenFooter, std::uint64_t maxKeySize);
+
+  ROOT::Internal::RRawFile *fRawFile;
+  std::uint64_t fMaxBlobSize;
+};

src/app_state.h

@@ -13,9 +13,10 @@ struct App_State {
 
   Delta_Time_Accum delta_time_accum;
 
-  FILE *inspected_file;
+  FILE       *inspected_file;
-  u8   *inspected_fmem;
+  u8         *inspected_fmem;
-  u64   inspected_file_size;
+  u64         inspected_file_size;
+  const char *inspected_fname;
 	// @Platform: inotify file descriptor
 	int inot;
 

src/mainloop.cpp

@@ -71,7 +71,6 @@ void run_main_loop(GLFWwindow *window, Arena *arena, App_State &app)
 		u64 time_since_prev_frame_us = chr::duration_cast<chr::microseconds>(frame_start - last_saved_time).count();
 		delta_time_ms = time_since_prev_frame_us * 0.001f;
 		last_saved_time = frame_start;
-		accum_dt_ms(app.delta_time_accum, delta_time_ms);
 
 		glfwPollEvents();
 

src/platform_linux.h

@@ -14,6 +14,7 @@ void os_open_and_map_file(const char *fname, App_State &app)
   if (!fmem)
     fprintf(stderr, "Failed to open file %s\n", fname);
 
+  app.inspected_fname = fname;
   app.inspected_file = file;
   app.inspected_file_size = fsize;
   app.inspected_fmem = reinterpret_cast<u8*>(fmem);

src/render.cpp

@@ -35,10 +35,16 @@ u32 mem_edit_bg_color_fn(const u8 *data, u64 off, const void *user_data)
 {
   const App_State *app = reinterpret_cast<const App_State *>(user_data);
   const RNTuple_Info &rinfo = app->rntinfo;
+  u64 rblob_sz = rinfo.rblob_header_size;
 
 #define COL(c) (ImColor((c)[0], (c)[1], (c)[2]))
-  if (rinfo.header.start <= off && off <= rinfo.header.end()) return COL(app->vsettings.col_header);
+  if (off <= rinfo.root_file_header_size) return COL(app->vsettings.col_tfile);
-  if (rinfo.footer.start <= off && off <= rinfo.footer.end()) return COL(app->vsettings.col_footer);
+  if (rinfo.rng_anchor_key.start <= off && off <= rinfo.rng_anchor_key.end()) return COL(app->vsettings.col_key);
+  if (rinfo.rng_header.start - rblob_sz <= off && off <= rinfo.rng_header.start) return COL(app->vsettings.col_key);
+  if (rinfo.rng_footer.start - rblob_sz <= off && off <= rinfo.rng_footer.start) return COL(app->vsettings.col_key);
+  if (rinfo.rng_anchor.start <= off && off <= rinfo.rng_anchor.end()) return COL(app->vsettings.col_anchor);
+  if (rinfo.rng_header.start <= off && off <= rinfo.rng_header.end()) return COL(app->vsettings.col_header);
+  if (rinfo.rng_footer.start <= off && off <= rinfo.rng_footer.end()) return COL(app->vsettings.col_footer);
 #undef COL
 
   return IM_COL32(0, 0, 0, 0);
@@ -61,8 +67,11 @@ Viewer_Settings make_viewer_settings()
 {
   Viewer_Settings settings {};
 #define COL(c, r, g, b) settings.c[0] = r/255.0, settings.c[1] = g/255.0, settings.c[2] = b/255.0
+  COL(col_anchor, 150, 150, 0);
   COL(col_header, 150, 0, 50);
   COL(col_footer, 50, 0, 150);
+  COL(col_key,    0, 100, 50);
+  COL(col_tfile,  90, 90, 90);
 #undef COL
   return settings;
 }
@@ -70,7 +79,7 @@ Viewer_Settings make_viewer_settings()
 internal
 void update_and_render(Arena *arena, App_State &app, f32 delta_time_ms)
 {
-  (void)delta_time_ms;
+  accum_dt_ms(app.delta_time_accum, delta_time_ms);
   
   ImGui::SetNextWindowPos({ 0, 0 });
   ImGui::SetNextWindowSize({ (f32)app.win_data.width, (f32)app.win_data.height });
@@ -91,7 +100,7 @@ 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.rntinfo.anchor);
-    ImGui::Text("Inspecting RNTuple '%s' (%s)", app.ntpl_name, ntpl_desc.c());
+    ImGui::Text("RNTuple '%s' (%s) from file \"%s\"", app.ntpl_name, ntpl_desc.c(), app.inspected_fname);
 
     // Draw stats
     {
@@ -122,8 +131,11 @@ void update_and_render(Arena *arena, App_State &app, f32 delta_time_ms)
       mem_edit.DrawContents(app.inspected_fmem, app.inspected_file_size);
 
       ImGui::TableNextColumn();
-      ImGui::ColorEdit3("Header", app.vsettings.col_header, ImGuiColorEditFlags_NoInputs);
+      ImGui::ColorEdit3("TFile",          app.vsettings.col_tfile,  ImGuiColorEditFlags_NoInputs);
-      ImGui::ColorEdit3("Footer", app.vsettings.col_footer, ImGuiColorEditFlags_NoInputs);
+      ImGui::ColorEdit3("RNTuple Anchor", app.vsettings.col_anchor, ImGuiColorEditFlags_NoInputs);
+      ImGui::ColorEdit3("RNTuple Header", app.vsettings.col_header, ImGuiColorEditFlags_NoInputs);
+      ImGui::ColorEdit3("RNTuple Footer", app.vsettings.col_footer, ImGuiColorEditFlags_NoInputs);
+      ImGui::ColorEdit3("TKey Header",    app.vsettings.col_key,    ImGuiColorEditFlags_NoInputs);
 
       ImGui::EndTable();
     }

src/render.h

@@ -1,6 +1,9 @@
 struct Viewer_Settings {
+  float col_anchor[3];
   float col_header[3];
   float col_footer[3];
+  float col_key[3];
+  float col_tfile[3];
 };
 
 struct Edit_Bg_Color_Data {

src/rntuple.cpp

@@ -26,13 +26,26 @@ RNTuple_Info get_rntuple_info(Arena *arena, const char *fname, const char *ntpl_
   const RNTuple *anchor = tfile->Get<RNTuple>(ntpl_name);
   if (anchor) {
     info.anchor = *anchor;
-    info.header.start = anchor->GetSeekHeader();
+    info.rng_header.start = anchor->GetSeekHeader();
-    info.header.len = anchor->GetNBytesHeader();
+    info.rng_header.len = anchor->GetNBytesHeader();
-    info.footer.start = anchor->GetSeekFooter();
+    info.rng_footer.start = anchor->GetSeekFooter();
-    info.footer.len = anchor->GetNBytesFooter();
+    info.rng_footer.len = anchor->GetNBytesFooter();
   } else {
     fprintf(stderr, "RNTuple '%s' not found in %s.\n", ntpl_name, fname);
   }
 
+  // TODO: proper error handling
+  auto raw_file = ROOT::Internal::RRawFile::Create(fname);
+  if (raw_file) {
+    PseudoMiniFileReader file_reader { raw_file.get() };
+    auto file_info = file_reader.GetNTupleProper(ntpl_name).Unwrap();
+    info.rng_anchor.start = file_info.anchor_seek;
+    info.rng_anchor.len = file_info.anchor_nbytes;
+    info.rng_anchor_key.start = file_info.anchor_key_seek;
+    info.rng_anchor_key.len = file_info.anchor_key_nbytes;
+    info.rblob_header_size = file_info.rblob_key_header_nbytes;
+    info.root_file_header_size = file_info.tfile_header_nbytes;
+  }
+
   return info;
 }

src/rntuple.h

@@ -8,6 +8,10 @@ struct Byte_Range {
 struct RNTuple_Info {
   RNTuple anchor;  
 
-  Byte_Range header;
+  u64 root_file_header_size;
-  Byte_Range footer;
+  u64 rblob_header_size;
+  Byte_Range rng_anchor;
+  Byte_Range rng_anchor_key;
+  Byte_Range rng_header;
+  Byte_Range rng_footer;
 };

src/rntviewer.cpp

@@ -18,6 +18,8 @@
 #define GLFW_INCLUDE_NONE
 #include <GLFW/glfw3.h>
 
+#include "PseudoMiniFile.hxx"
+
 #include "types.h"
 #include "defer.hpp"
 #include "mem.h"