X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/mLib/blobdiff_plain/88bd7f658d494cd5aae62972e39294c2e01c2da3..54116dad62ece5b7ca1b6622c6f26b938ac53c03:/tv.c

diff --git a/tv.c b/tv.c
index eeeb8b0..8f41a2f 100644
--- a/tv.c
+++ b/tv.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: tv.c,v 1.4 1999/05/17 20:37:52 mdw Exp $
+ * $Id: tv.c,v 1.5 1999/05/21 22:13:12 mdw Exp $
  *
  * Manipulation of timeval structures
  *
@@ -30,6 +30,10 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: tv.c,v $
+ * Revision 1.5  1999/05/21 22:13:12  mdw
+ * Moved most of the code into exported macros.  The main functions now
+ * implemented using the macros.
+ *
  * Revision 1.4  1999/05/17 20:37:52  mdw
  * New function `tv_addl' to add a literal to a time value.  Use magical
  * `MILLION' constant in place of 1000000 for ease of reading.
@@ -50,10 +54,6 @@
 #include <sys/time.h>
 #include "tv.h"
 
-/*----- A macro to make reading easier ------------------------------------*/
-
-#define MILLION 1000000
-
 /*----- Main code ---------------------------------------------------------*/
 
 /* --- @tv_add@ --- *
@@ -69,12 +69,7 @@
 void tv_add(struct timeval *dst,
 	    const struct timeval *a, const struct timeval *b)
 {
-  dst->tv_sec = a->tv_sec + b->tv_sec;
-  dst->tv_usec = a->tv_usec + b->tv_usec;
-  if (dst->tv_usec >= MILLION) {
-    dst->tv_usec -= MILLION;
-    dst->tv_sec++;
-  }
+  TV_ADD(dst, a, b);
 }
 
 /* --- @tv_addl@ --- *
@@ -91,12 +86,7 @@ void tv_add(struct timeval *dst,
 void tv_addl(struct timeval *dst, const struct timeval *a,
 	     time_t sec, unsigned long usec)
 {
-  dst->tv_sec = a->tv_sec + sec;
-  dst->tv_usec = a->tv_usec + usec;
-  if (dst->tv_usec >= MILLION) {
-    dst->tv_usec -= MILLION;
-    dst->tv_sec++;
-  }
+  TV_ADDL(dst, a, sec, usec);
 }
 
 /* --- @tv_sub@ --- *
@@ -112,13 +102,24 @@ void tv_addl(struct timeval *dst, const struct timeval *a,
 void tv_sub(struct timeval *dst,
 	    const struct timeval *a, const struct timeval *b)
 {
-  dst->tv_sec = a->tv_sec - b->tv_sec;
-  if (a->tv_usec >= b->tv_usec)
-    dst->tv_usec = a->tv_usec - b->tv_usec;
-  else {
-    dst->tv_usec = a->tv_usec + MILLION - b->tv_usec;
-    dst->tv_sec--;
-  }
+  TV_SUB(dst, a, b);
+}
+
+/* --- @tv_subl@ --- *
+ *
+ * Arguments:	@struct timeval *dst@ = destination block
+ *		@const struct timeval *a@ = source blocks
+ *		@time_t sec@, @unsigned long usec@ = time to subtract
+ *
+ * Returns:	---
+ *
+ * Use:		Subtracts a literal time in seconds and microseconds.
+ */
+
+void tv_subl(struct timeval *dst, const struct timeval *a,
+		    time_t sec, unsigned long usec)
+{
+  TV_SUBL(dst, a, sec, usec);
 }
 
 /* --- @tv_cmp@ --- *
@@ -132,6 +133,8 @@ void tv_sub(struct timeval *dst,
 
 int tv_cmp(const struct timeval *a, const struct timeval *b)
 {
+  /* --- This is more awkward than the case the macro deals with --- */
+
   if (a->tv_sec > b->tv_sec)
     return (1);
   else if (a->tv_sec < b->tv_sec)