4 files changed, 32 insertions, 1 deletions

diff --git a/disasm/ndisasm.c b/disasm/ndisasm.c
index f3c23b00..01e0c557 100644
--- a/disasm/ndisasm.c
+++ b/disasm/ndisasm.c
@@ -280,8 +280,10 @@ int main(int argc, char **argv)
                     pname, filename, strerror(errno));
             return 1;
         }
-    } else
+    } else {
+        nasm_set_binary_mode(stdin);
         fp = stdin;
+    }
 
     if (initskip > 0)
         skip(initskip, fp);
diff --git a/include/nasmlib.h b/include/nasmlib.h
index 940f1cb7..c4b4ac4c 100644
--- a/include/nasmlib.h
+++ b/include/nasmlib.h
@@ -365,6 +365,8 @@ enum file_flags {
 FILE *nasm_open_read(const char *filename, enum file_flags flags);
 FILE *nasm_open_write(const char *filename, enum file_flags flags);
 
+void nasm_set_binary_mode(FILE *f);
+
 /* Probe for existence of a file */
 bool nasm_file_exists(const char *filename);
 
diff --git a/nasmlib/file.c b/nasmlib/file.c
index a8cd3057..62b854de 100644
--- a/nasmlib/file.c
+++ b/nasmlib/file.c
@@ -148,6 +148,11 @@ os_filename os_mangle_filename(const char *filename)
 
 #endif
 
+void nasm_set_binary_mode(FILE *f)
+{
+	os_set_binary_mode(f);
+}
+
 FILE *nasm_open_read(const char *filename, enum file_flags flags)
 {
     FILE *f = NULL;
diff --git a/nasmlib/file.h b/nasmlib/file.h
index 4f0420ec..fc8f893d 100644
--- a/nasmlib/file.h
+++ b/nasmlib/file.h
@@ -103,6 +103,24 @@ typedef struct _stati64 os_struct_stat;
 # define os_stat  _wstati64
 # define os_fstat _fstati64
 
+/*
+ * On Win32/64, freopen() and _wfreopen() fails when the mode string
+ * is with the letter 'b' that represents to set binary mode. On
+ * POSIX operating systems, the 'b' is ignored, without failure.
+ */
+
+#include <io.h>
+#include <fcntl.h>
+
+static inline void os_set_binary_mode(FILE *f) {
+    int ret = _setmode(_fileno(f), _O_BINARY);
+
+    if (ret == -1) {
+        nasm_fatalf(ERR_NOFILE, "unable to open file: %s",
+                    strerror(errno));
+    }
+}
+
 #else  /* not _WIN32 */
 
 typedef const char *os_filename;
@@ -117,6 +135,10 @@ static inline void os_free_filename(os_filename filename)
     (void)filename;             /* Nothing to do */
 }
 
+static inline void os_set_binary_mode(FILE *f) {
+    (void)f;
+}
+
 # define os_fopen  fopen
 
 #if defined(HAVE_FACCESSAT) && defined(AT_EACCESS)