ELF exporting takes a target file

2 files changed, 7 insertions, 12 deletions

diff --git a/chapter21/src/main/java/com/seaofnodes/simple/codegen/CodeGen.java b/chapter21/src/main/java/com/seaofnodes/simple/codegen/CodeGen.java
index 88144a1d..8788d109 100644
--- a/chapter21/src/main/java/com/seaofnodes/simple/codegen/CodeGen.java
+++ b/chapter21/src/main/java/com/seaofnodes/simple/codegen/CodeGen.java
@@ -2,11 +2,10 @@ package com.seaofnodes.simple.codegen;
 
 import com.seaofnodes.simple.*;
 import com.seaofnodes.simple.node.*;
-
 import com.seaofnodes.simple.print.*;
 import com.seaofnodes.simple.type.*;
-
 import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.util.BitSet;
 import java.util.HashMap;
 import java.util.IdentityHashMap;
@@ -323,11 +322,11 @@ public class CodeGen {
 
     // ---------------------------
     // Exporting to external formats
-    public CodeGen exportELF() {
+    public CodeGen exportELF(String fname) throws IOException {
         assert _phase == Phase.Encoding;
         _phase = Phase.Export;
         ElfFile obj = new ElfFile(this);
-        obj.export();
+        obj.export(fname);
         return this;
     }
 
diff --git a/chapter21/src/main/java/com/seaofnodes/simple/codegen/ElfFile.java b/chapter21/src/main/java/com/seaofnodes/simple/codegen/ElfFile.java
index c39c5dc2..019cdf90 100644
--- a/chapter21/src/main/java/com/seaofnodes/simple/codegen/ElfFile.java
+++ b/chapter21/src/main/java/com/seaofnodes/simple/codegen/ElfFile.java
@@ -258,7 +258,7 @@ public class ElfFile {
         }
     }
 
-    public void export() {
+    public void export(String fname) throws IOException {
         DataSection strtab = new DataSection(".strtab", 3 /* SHT_SYMTAB */);
         // first byte is reserved for an empty string
         strtab._contents.write(0);
@@ -375,13 +375,9 @@ public class ElfFile {
         }
         assert out.position() == size;
 
-        try {
-            BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("a.o"));
-            bos.write(out.array());
-            bos.close();
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
+        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(fname));
+        bos.write(out.array());
+        bos.close();
     }
 
 }