improve title

src/render.cpp

@@ -143,11 +143,14 @@ void init_viewer(Arena *arena, App_State &app, u16 n_cols)
   viewer.mem_edit = make_memory_editor(app, (i32)n_cols);
   
   // Init title
-  if (app.tfile_data.sections[Sec_RNTuple_Anchor].head) {
+  u32 n_ntuples = app.tfile_data.sections[Sec_RNTuple_Anchor].count;
+  if (n_ntuples) {
     Temp scratch = scratch_begin(&arena, 1);
     defer { scratch_end(scratch); };
 
-    const RNTuple_Anchor_Info *anchor = (const RNTuple_Anchor_Info *)app.tfile_data.sections[Sec_RNTuple_Anchor].head->info;
+    if (n_ntuples == 1) {
+      Section *sec = app.tfile_data.sections[Sec_RNTuple_Anchor].head;
+      const RNTuple_Anchor_Info *anchor = (const RNTuple_Anchor_Info *)sec->info;
       String8 ntpl_desc = rntuple_description(scratch.arena, anchor->anchor);
       if (rntuple_is_old_version(anchor->anchor)) {
         viewer.col_title[0] = 1.f;
@@ -157,6 +160,17 @@ void init_viewer(Arena *arena, App_State &app, u16 n_cols)
         viewer.col_title[0] = viewer.col_title[1] = viewer.col_title[2] = 1.f;
         viewer.title = push_str8f(arena, "\"%s\" (%s) from file \"%s\"", anchor->name.c(), ntpl_desc.c(), app.inspected_file.name.c());
       }
+    } else {
+      String8 title = str8("RNTuples");
+      for (Section *sec = app.tfile_data.sections[Sec_RNTuple_Anchor].head; sec; sec = sec->next) {
+        const RNTuple_Anchor_Info *anchor = (const RNTuple_Anchor_Info *)sec->info;
+        title = str8_concat(scratch.arena, title, push_str8f(scratch.arena, " \"%s\",", anchor->name));
+      }
+      title.size -= 1; // strip trailing comma
+      title = str8_concat(scratch.arena, title, push_str8f(scratch.arena, " from file \"%s\"", app.inspected_file.name.c()));
+      viewer.col_title[0] = viewer.col_title[1] = viewer.col_title[2] = 1.f;
+      viewer.title = str8_from_buf(arena, title.str, title.size);
+    }
   } else {
     viewer.col_title[0] = viewer.col_title[1] = viewer.col_title[2] = 1.f;
     viewer.title = push_str8f(arena, "(no RNTuple) from file \"%s\"", app.inspected_file.name.c());

src/str.cpp

@@ -40,6 +40,17 @@ String8 str8_from_buf(Arena *arena, const u8 *buf, u64 size)
   return s;
 }
 
+String8 str8_concat(Arena *arena, String8 a, String8 b)
+{
+  String8 res;
+  res.size = a.size + b.size;
+  res.str = arena_push_array_nozero<u8>(arena, res.size + 1);
+  memcpy(res.str, a.str, a.size);
+  memcpy(res.str + a.size, b.str, b.size);
+  res.str[res.size] = 0;
+  return res;
+}
+
 internal
 String8 to_pretty_size(Arena *arena, u64 bytes)
 {

src/tfile.cpp

@@ -79,8 +79,9 @@ enum {
 // Examines the innards of a TFile to get byte range info about the TKeys.
 // Additionally, it returns the names of all the RNTuples stored in it.
 // `data` should point to the beginning of a ROOT file.
+// If `ntpl_name` is non-empty, skip all RNTuples that are not the one specified.
 internal
-b8 walk_tkeys(Arena *arena, const u8 *data, u64 data_len, u32 flags, TFile_Data &tfile_data)
+b8 walk_tkeys(Arena *arena, const u8 *data, u64 data_len, u32 flags, TFile_Data &tfile_data, String8 ntpl_name)
 { 
   u64 cur = 4; // offset of header version
   if (data_len < cur) {
@@ -270,6 +271,8 @@ b8 walk_tkeys(Arena *arena, const u8 *data, u64 data_len, u32 flags, TFile_Data
       if (key_has_class_name("ROOT::RNTuple") || key_has_class_name("ROOT::Experimental::RNTuple")) {
         u64 name_off = cname_off + cname_len + 1;
         u8 name_len = data[name_off];
+        const char *rntuple_name = (const char *)data + name_off + 1;
+        if (!ntpl_name.size || strncmp((const char *)ntpl_name.str, rntuple_name, name_len) == 0) {
           RNTuple_Anchor_Info *rntuple_info = arena_push<RNTuple_Anchor_Info>(arena);
           rntuple_info->offset_in_file = cur;
           if (name_len) {
@@ -293,7 +296,9 @@ b8 walk_tkeys(Arena *arena, const u8 *data, u64 data_len, u32 flags, TFile_Data
           sec_anchor->range.len = n_bytes - keylen;
           sec_anchor->pre_size = keylen;
           sec_anchor->post_size = 8;
-        
+        } else {
+          fprintf(stderr, "Note: skipped RNTuple '%s' because it doesn't match the name '%s' we're looking for.\n", rntuple_name, ntpl_name.c());
+        }
       } else if (key_has_class_name("RBlob")) {
         if (!sections[Sec_Page].head) {
           push_section(arena, tfile_data, Sec_Page)->pre_size = keylen;
@@ -365,6 +370,7 @@ b8 walk_tkeys(Arena *arena, const u8 *data, u64 data_len, u32 flags, TFile_Data
   return true;
 }
 
+// Creates the RNTuple_Header and Footer sections by associating them to their proper RBlobs and Anchor.
 internal
 void map_rntuple_rblobs(Arena *arena, TFile_Data &tfile_data)
 {
@@ -425,9 +431,9 @@ void map_rntuple_rblobs(Arena *arena, TFile_Data &tfile_data)
 }
 
 internal
-b8 get_tfile_data(Arena *arena, const Inspected_File &file, u32 walk_tkeys_flags, String8 &ntpl_name, TFile_Data &tfile_data)
+b8 get_tfile_data(Arena *arena, const Inspected_File &file, u32 walk_tkeys_flags, String8 ntpl_name, TFile_Data &tfile_data)
 {  
-  b8 success = walk_tkeys(arena, file.mem, file.size, walk_tkeys_flags, tfile_data);
+  b8 success = walk_tkeys(arena, file.mem, file.size, walk_tkeys_flags, tfile_data, ntpl_name);
   if (success) {
     // TODO: if ntpl_name is non-empty, only pick the given RNTuple
     map_rntuple_rblobs(arena, tfile_data);