wat2wasm: Always write output to a file (#682)

This involves deriving the output filename from the input
filename when none is otherwise specified.

Also split out filename handling utilities and add unittests
for them.

1 files changed, 4 insertions, 14 deletions

diff --git a/src/binary-reader-objdump.cc b/src/binary-reader-objdump.cc
index 9bacba58..cef44c18 100644
--- a/src/binary-reader-objdump.cc
+++ b/src/binary-reader-objdump.cc
@@ -24,6 +24,7 @@
 #include <vector>
 
 #include "src/binary-reader-nop.h"
+#include "src/filenames.h"
 #include "src/literal.h"
 
 namespace wabt {
@@ -102,20 +103,9 @@ Result BinaryReaderObjdumpBase::BeginModule(uint32_t version) {
       printf("Code Disassembly:\n\n");
       break;
     case ObjdumpMode::Prepass: {
-      const char* last_slash = strrchr(options_->filename, '/');
-      const char* last_backslash = strrchr(options_->filename, '\\');
-      const char* basename;
-      if (last_slash && last_backslash) {
-        basename = std::max(last_slash, last_backslash) + 1;
-      } else if (last_slash) {
-        basename = last_slash + 1;
-      } else if (last_backslash) {
-        basename = last_backslash + 1;
-      } else {
-        basename = options_->filename;
-      }
-
-      printf("%s:\tfile format wasm %#x\n", basename, version);
+      string_view basename = GetBasename(options_->filename);
+      printf("%s:\tfile format wasm %#x\n", basename.to_string().c_str(),
+             version);
       break;
     }
     case ObjdumpMode::RawData: