Merge branch 'js/mingw-fflush-errno'

* js/mingw-fflush-errno:
  maybe_flush_or_die: move a too-loose Windows specific error

2 files changed, 25 insertions, 0 deletions

diff --git a/compat/mingw.c b/compat/mingw.c
index afc892d6b1..4e6383898c 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -335,6 +335,28 @@ FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 	return freopen(filename, otype, stream);
 }
 
+#undef fflush
+int mingw_fflush(FILE *stream)
+{
+	int ret = fflush(stream);
+
+	/*
+	 * write() is used behind the scenes of stdio output functions.
+	 * Since git code does not check for errors after each stdio write
+	 * operation, it can happen that write() is called by a later
+	 * stdio function even if an earlier write() call failed. In the
+	 * case of a pipe whose readable end was closed, only the first
+	 * call to write() reports EPIPE on Windows. Subsequent write()
+	 * calls report EINVAL. It is impossible to notice whether this
+	 * fflush invocation triggered such a case, therefore, we have to
+	 * catch all EINVAL errors whole-sale.
+	 */
+	if (ret && errno == EINVAL)
+		errno = EPIPE;
+
+	return ret;
+}
+
 /*
  * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
  * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
diff --git a/compat/mingw.h b/compat/mingw.h
index 61a652138a..eeb08d120b 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -185,6 +185,9 @@ FILE *mingw_fopen (const char *filename, const char *otype);
 FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream);
 #define freopen mingw_freopen
 
+int mingw_fflush(FILE *stream);
+#define fflush mingw_fflush
+
 char *mingw_getcwd(char *pointer, int len);
 #define getcwd mingw_getcwd