[PATCH v3 2/8] mingw: work around irregular failures of unlink on windows

From

Heiko Voigt <hvoigt@hvoigt.net>

Date

Dec 14, 2010, 22:11 UTC

Message-ID

<20101214221134.GC4084@sandbox>

In-Reply-To

<20101214220604.GA4084@sandbox>

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 compat/mingw.c |   31 +++++++++++++++++++++++++++++--
 1 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index a7e1c6b..52183a7 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3,6 +3,8 @@
 #include <conio.h>
 #include "../strbuf.h"
 
+static const int delay[] = { 0, 1, 10, 20, 40 };
+
 int err_win_to_posix(DWORD winerr)
 {
 	int error = ENOSYS;
@@ -116,12 +118,38 @@ int err_win_to_posix(DWORD winerr)
 	return error;
 }
 
+static inline int is_file_in_use_error(DWORD errcode)
+{
+	switch(GetLastError()) {
+	case ERROR_SHARING_VIOLATION:
+	case ERROR_ACCESS_DENIED:
+		return 1;
+	}
+
+	return 0;
+}
+
 #undef unlink
 int mingw_unlink(const char *pathname)
 {
+	int ret, tries = 0;
+
 	/* read-only files cannot be removed */
 	chmod(pathname, 0666);
-	return unlink(pathname);
+	while ((ret = unlink(pathname)) == -1 && tries < ARRAY_SIZE(delay)) {
+		if (!is_file_in_use_error(GetLastError()))
+			break;
+		/*
+		 * We assume that some other process had the source or
+		 * destination file open at the wrong moment and retry.
+		 * In order to give the other process a higher chance to
+		 * complete its operation, we give up our time slice now.
+		 * If we have to retry again, we do sleep a bit.
+		 */
+		Sleep(delay[tries]);
+		tries++;
+	}
+	return ret;
 }
 
 #undef open
@@ -1257,7 +1285,6 @@ int mingw_rename(const char *pold, const char *pnew)
 {
 	DWORD attrs, gle;
 	int tries = 0;
-	static const int delay[] = { 0, 1, 10, 20, 40 };
 
 	/*
 	 * Try native rename() first to get errno right.

-- 
1.7.3.3.566.gf422f