start varaible size row length

Makefile

@@ -1,8 +1,9 @@
 SRC:=src/*.cpp
 INCLUDE:=include/
 BUILD:=build
-CFLAGS:=-Wall -pedantic -O3 -march=native --std=gnu++20 -fgraphite -flto
-LFLAGS:=-O2 -flto -ltickit -lfmt
+FEATURES?=-DFIXED_ROW_SIZE=24
+CFLAGS:= $(FEATURES) -Wall -pedantic -O3 -march=native --std=gnu++20 -fgraphite -flto
+LFLAGS:=-O3 -flto -lfmt
 
 hexview:
 	g++ $(SRC) $(CFLAGS) -I$(INCLUDE) -o $(BUILD)/$@ $(LFLAGS)

include/graphics.hpp

@@ -1,15 +0,0 @@
-#pragma once
-
-#include <memory>
-
-namespace gr
-{
-  struct Context
-  {
-    Context();
-    ~Context();
-  private:
-    struct _impl;
-    std::unique_ptr<_impl> impl;
-  };
-}

src/graphics.cpp

@@ -1,33 +0,0 @@
-#include <tickit.h>
-
-#include <graphics.hpp>
-
-static int on_geomchange(TickitWindow* win, TickitEventFlags flags, void* info, void* data)
-{
-  tickit_window_expose(win, NULL);
-  gr::Context* ctx = (gr::Context*)data;
-  
-}
-
-namespace gr
-{
-  struct Context::_impl
-  {
-    Tickit* context;
-    TickitWindow* root;
-  };
-
-  Context::Context()
-    : impl(std::make_unique<_impl>())
-  {
-    impl->context = tickit_new_stdtty();
-    impl->root = tickit_get_rootwin(impl->context);
-
-    if(!impl->root) throw "couldn't create window.";
-  }
-
-  Context::~Context()
-  {
-    tickit_unref(impl->context);
-  }
-}

src/hex.cpp

@@ -20,18 +20,30 @@ const static constexpr char ascii_map[255] = {
 					      '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', '.', 	      
 };
 
-const constexpr int ROW_SZ = 24;
+#ifndef FIXED_ROW_SIZE
+#include <alloca.h>
+#endif
+
+#ifdef FIXED_ROW_SIZE
+constexpr int ROW_SZ = FIXED_ROW_SIZE;
+#endif
 
 namespace hv {
   void print_screen(const span<unsigned char> memory, unsigned long offset)
   {
+#ifndef FIXED_ROW_SIZE
+#define S (const char*)
+    int ROW_SZ = 24;
+#else
+#define S
+#endif
     fmt::print("0x{:016x}  ", offset);
     char ascii[1 + ROW_SZ];
     ascii[ROW_SZ] = 0;
     std::size_t i=0;
     for(;i<memory.size();i++) {
       if (i && i % ROW_SZ == 0) {
-	fmt::print("  {}", ascii);
+	fmt::print("  {}", S ascii);
 	fmt::print("\n0x{:016x}  ", i+offset);
       }
       fmt::print("{:02x} ", memory[i]);
@@ -45,6 +57,6 @@ namespace hv {
 	  fmt::print("   ");
 	  
       }
-    fmt::print("  {}", ascii);    
+    fmt::print("  {}", S ascii);    
   }
 }

src/main.cpp

@@ -2,7 +2,6 @@
 #include <fstream>
 #include <memory-map.hpp>
 #include <hex.hpp>
-#include <graphics.hpp>
 
 std::ifstream::pos_type filesize(const char* filename)
 {