diff --git a/src/build_log.cc b/src/build_log.cc
old mode 100644
new mode 100755
index 3073f7fbf9..8c45c77747
--- a/src/build_log.cc
+++ b/src/build_log.cc
@@ -54,7 +54,7 @@ bool BuildLog::OpenForWrite(const string& path, string* err) {
     *err = strerror(errno);
     return false;
   }
-  setvbuf(log_file_, NULL, _IOLBF, 0);
+  setvbuf(log_file_, NULL, _IOLBF, BUFSIZ);
 
   if (ftell(log_file_) == 0) {
     if (fwrite(kFileSignature, sizeof(kFileSignature) - 1, 1, log_file_) < 1) {
diff --git a/src/build_log_test.cc b/src/build_log_test.cc
old mode 100644
new mode 100755
index 8bb2bfaaff..1df28db7fe
--- a/src/build_log_test.cc
+++ b/src/build_log_test.cc
@@ -16,6 +16,10 @@
 
 #include "test.h"
 
+#ifdef WIN32
+#include <fcntl.h>
+#endif
+
 static const char kTestFilename[] = "BuildLogTest-tempfile";
 
 struct BuildLogTest : public StateTestWithBuiltinRules {
@@ -90,7 +94,14 @@ TEST_F(BuildLogTest, Truncate) {
   // For all possible truncations of the input file, assert that we don't
   // crash or report an error when parsing.
   for (off_t size = statbuf.st_size; size > 0; --size) {
+#ifndef WIN32
     ASSERT_EQ(0, truncate(kTestFilename, size));
+#else
+    int fh;
+    ASSERT_EQ(0, _sopen_s(&fh, kTestFilename, _O_RDWR | _O_CREAT, _SH_DENYNO, _S_IREAD | _S_IWRITE));
+    ASSERT_EQ(0, _chsize(fh, size));
+    _close(fh);
+#endif
 
     BuildLog log2;
     EXPECT_TRUE(log2.Load(kTestFilename, &err));
diff --git a/src/ninja_test.cc b/src/ninja_test.cc
old mode 100644
new mode 100755
index 6e3f549f35..a5ef3ab751
--- a/src/ninja_test.cc
+++ b/src/ninja_test.cc
@@ -217,7 +217,7 @@ TEST_F(StatTest, Middle) {
 #ifndef _mktemp_s
 /// mingw has no mktemp.  Implement one with the same type as the one
 /// found in the Windows API.
-int _mktemp_s(const char* templ) {
+int _mktemp_s(char* templ) {
   char* ofs = strchr(templ, 'X');
   sprintf(ofs, "%d", rand() % 1000000);
   return 0;
diff --git a/src/util.cc b/src/util.cc
old mode 100644
new mode 100755
index 14b3379b5f..d5a8f1f331
--- a/src/util.cc
+++ b/src/util.cc
@@ -25,7 +25,10 @@
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+
+#ifndef _WIN32
 #include <sys/time.h>
+#endif
 
 #include <vector>
 
diff --git a/src/util.h b/src/util.h
old mode 100644
new mode 100755
index 794177dffd..c9e06f4d72
--- a/src/util.h
+++ b/src/util.h
@@ -46,4 +46,8 @@ int ReadFile(const string& path, string* contents, string* err);
 /// time.
 int64_t GetTimeMillis();
 
+#ifdef _WIN32
+#define snprintf _snprintf
+#endif
+
 #endif  // NINJA_UTIL_H_