Refactor code generation: use shared/context_struct.h

This allows #include'ing `context_struct.h` in the stack walker
implementation as well

shared/context_struct.h

@@ -0,0 +1,5 @@
+#include <stdint.h>
+
+typedef struct {
+    uintptr_t rip, rsp, rbp;
+} unwind_context_t;

src/.gitignore

@@ -1 +1,2 @@
 dwarf-assembly
+gen_*.hpp

src/CodeGenerator.cpp

@@ -1,4 +1,5 @@
 #include "CodeGenerator.hpp"
+#include "gen_context_struct.hpp"
 
 using namespace std;
 
@@ -6,10 +7,6 @@ static const char* PRELUDE =
 "#include <stdint.h>\n"
 "#include <assert.h>\n"
 "\n"
-"typedef struct {\n"
-"    uintptr_t rip, rsp, rbp;\n"
-"} unwind_context_t;\n"
-"\n"
 "typedef unwind_context_t (*_fde_func_t)(unwind_context_t, uintptr_t);\n"
 ;
 
@@ -25,7 +22,8 @@ void CodeGenerator::generate() {
 }
 
 void CodeGenerator::gen_of_dwarf() {
-    os << PRELUDE << '\n' << endl;
+    os << CONTEXT_STRUCT_STR << '\n'
+       << PRELUDE << '\n' << endl;
 
     vector<LookupEntry> lookup_entries;
 

src/Makefile

@@ -10,13 +10,18 @@ OBJS=DwarfReader.o SimpleDwarf.o CodeGenerator.o main.o
 
 all: $(TARGET)
 
-$(TARGET): $(OBJS)
+$(TARGET): gen_context_struct.hpp $(OBJS)
 	$(CXX) -o $@ $(CXXFLAGS) $^ $(CXXLIBS)
 
+gen_context_struct.hpp: ../shared/context_struct.h
+	echo "static const char* CONTEXT_STRUCT_STR =" > $@
+	sed 's/"/\\"/g' $< | sed 's/^\(.*\)$$/"\1\\n"/g' >> $@
+	echo ";" >> $@
+
 %.o: %.cpp
 	$(CXX) -o $@ $(CXXFLAGS) -c $<
 
 
 .PHONY: clean
 clean:
-	rm -f $(TARGET) *.o
+	rm -f $(TARGET) *.o gen_*.hpp