add mkostemp, mkstemps, and mkostemps functions and reorganize temp internals

based on patch contributed by Anthony G. Basile (blueness)

some issues remain with the filename generation algorithm and other
small bugs, but this patch has been sitting around long enough that I
feel it's best to get it committed and then work out any remaining
issues.

1 files changed, 21 insertions, 0 deletions

diff --git a/src/temp/__randname.c b/src/temp/__randname.c
new file mode 100644
index 00000000..b097576d
--- /dev/null
+++ b/src/temp/__randname.c
@@ -0,0 +1,21 @@
+#include <string.h>
+#include <time.h>
+#include <stdint.h>
+
+int __clock_gettime(clockid_t, struct timespec *);
+
+/* This assumes that a check for the
+   template size has alrady been made */
+char *__randname(char *template)
+{
+	int i;
+	struct timespec ts;
+	unsigned long r;
+
+	__clock_gettime(CLOCK_REALTIME, &ts);
+	r = ts.tv_nsec*65537 ^ (uintptr_t)&ts / 16 + (uintptr_t)template;
+	for (i=0; i<6; i++, r>>=5)
+		template[i] = 'A'+(r&15)+(r&16)*2;
+
+	return template;
+}