Add a touch_file() function to compat so we can update cache mtimes.

svn:r5067

src/common/compat.c

@@ -80,6 +80,12 @@ const char compat_c_id[] = "$Id$";
 #ifdef HAVE_PTHREAD_H
 #include <pthread.h>
 #endif
+#ifdef HAVE_UTIME_H
+#include <utime.h>
+#endif
+#ifdef HAVE_SYS_UTIME_H
+#include <sys/utime.h>
+#endif
 
 #include "log.h"
 #include "util.h"
@@ -269,6 +275,15 @@ replace_file(const char *from, const char *to)
 #endif
 }
 
+/** Change <b>fname</b>'s modification time to now. */
+int
+touch_file(const char *fname)
+{
+  if (utime(fname, NULL)!=0)
+    return -1;
+  return 0;
+}
+
 /** Turn <b>socket</b> into a nonblocking socket.
  */
 void

src/common/compat.h

@@ -127,6 +127,7 @@ struct tm *tor_gmtime_r(const time_t *timep, struct tm *result);
 
 /* ===== File compatibility */
 int replace_file(const char *from, const char *to);
+int touch_file(const char *fname);
 
 #ifdef MS_WINDOWS
 #define PATH_SEPARATOR "\\"