[Qemu-devel] [PATCH] w32: Add implementation of gmtime_r, localtime_r

[Stefan Weil <sw@weilnetz.de>]

Those functions are missing in MinGW.

Some versions of MinGW-w64 include defines for gmtime_r and localtime_r.
Older versions of these macros are buggy (they return a pointer to a
static variable), therefore we don't want them. Newer versions are
similar to the code used here, but without the memset.

The implementation which is used here is not strictly reentrant,
but sufficiently good for QEMU on w32 or w64.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
---
 oslib-win32.c   |   22 ++++++++++++++++++++++
 qemu-os-win32.h |    6 ++++++
 2 files changed, 28 insertions(+)

diff --git a/oslib-win32.c b/oslib-win32.c
index ffbc6d0..2acbf9b 100644
--- a/oslib-win32.c
+++ b/oslib-win32.c
@@ -74,6 +74,28 @@ void qemu_vfree(void *ptr)
     VirtualFree(ptr, 0, MEM_RELEASE);
 }
 
+struct tm *gmtime_r(const time_t *timep, struct tm *result)
+{
+    struct tm *p = gmtime(timep);
+    memset(result, 0, sizeof(*result));
+    if (p) {
+        *result = *p;
+        p = result;
+    }
+    return p;
+}
+
+struct tm *localtime_r(const time_t *timep, struct tm *result)
+{
+    struct tm *p = localtime(timep);
+    memset(result, 0, sizeof(*result));
+    if (p) {
+        *result = *p;
+        p = result;
+    }
+    return p;
+}
+
 void socket_set_block(int fd)
 {
     unsigned long opt = 0;
diff --git a/qemu-os-win32.h b/qemu-os-win32.h
index 753679b..3b5a35b 100644
--- a/qemu-os-win32.h
+++ b/qemu-os-win32.h
@@ -68,6 +68,12 @@
 /* Declaration of ffs() is missing in MinGW's strings.h. */
 int ffs(int i);
 
+/* Missing POSIX functions. Don't use MinGW-w64 macros. */
+#undef gmtime_r
+struct tm *gmtime_r(const time_t *timep, struct tm *result);
+#undef localtime_r
+struct tm *localtime_r(const time_t *timep, struct tm *result);
+
 static inline void os_setup_signal_handling(void) {}
 static inline void os_daemonize(void) {}
 static inline void os_setup_post(void) {}
-- 
1.7.10