move magic check to PE layer

src/pe/pe.c

@@ -408,6 +408,20 @@ pe_subsystem_from_string(String8 string)
 ////////////////////////////////
 //~ rjf: Parser Functions
 
+internal B32
+pe_check_magic(String8 data)
+{
+  B32 is_pe = 0;
+  PE_DosHeader dos_header = {0};
+  str8_deserial_read_struct(data, 0, &dos_header);
+  if (dos_header.magic == PE_DOS_MAGIC) {
+    U32 pe_magic = 0;
+    str8_deserial_read_struct(data, dos_header.coff_file_offset, &pe_magic);
+    is_pe= pe_magic == PE_MAGIC;
+  }
+  return is_pe;
+}
+
 internal PE_BinInfo
 pe_bin_info_from_data(Arena *arena, String8 data)
 {

src/pe/pe.h

@@ -1072,6 +1072,7 @@ internal String8 pe_string_from_dll_characteristics(Arena *arena, PE_DllCharacte
 ////////////////////////////////
 //~ rjf: Parser Functions
 
+internal B32        pe_check_magic(String8 data);
 internal PE_BinInfo pe_bin_info_from_data(Arena *arena, String8 data);
 
 internal PE_DebugInfoList           pe_parse_debug_directory(Arena *arena, String8 raw_image, String8 raw_debug_dir);

src/raddump/raddump.c

@@ -214,14 +214,6 @@ rd_format_line_from_voff(Arena *arena, RDI_Parsed *rdi, U64 voff, PathStyle path
   return result;
 }
 
-internal B32
-rd_is_pe(String8 raw_data)
-{
-  PE_DosHeader header = {0};
-  str8_deserial_read_struct(raw_data, 0, &header);
-  return header.magic == PE_DOS_MAGIC;
-}
-
 internal B32
 rd_is_rdi(String8 raw_data)
 {
@@ -316,7 +308,7 @@ rd_format_preamble(Arena *arena, String8List *out, String8 indent, String8 input
     input_type_string = "Big Obj";
   } else if (coff_is_obj(raw_data)) {
     input_type_string = "Obj";
-  } else if (rd_is_pe(raw_data)) {
+  } else if (pe_check_magic(raw_data)) {
     input_type_string = "COFF/PE";
   } else if (rd_is_rdi(raw_data)) {
     input_type_string = "RDI";

src/raddump/raddump.h

@@ -140,7 +140,6 @@ typedef struct RD_Line
 
 // raddump
 
-internal B32 rd_is_pe (String8 raw_data);
 internal B32 rd_is_rdi(String8 raw_data);
 
 internal String8 rd_string_from_flags(Arena *arena, String8List list, U64 remaining_flags);

src/raddump/raddump_main.c

@@ -269,7 +269,7 @@ entry_point(CmdLine *cmdline)
     coff_print_big_obj(arena, out, indent, raw_data, opts);
   } else if (coff_is_obj(raw_data)) {
     coff_print_obj(arena, out, indent, raw_data, opts);
-  } else if (rd_is_pe(raw_data)) {
+  } else if (pe_check_magic(raw_data)) {
     RDI_Parsed *rdi = 0;
     if (!(opts & RD_Option_NoRdi)) {
       rdi = rd_rdi_from_pe(arena, file_path, raw_data);