43075: Support nanosecond-precision time formatting

* Teach ztrftime() %9. and %N for nanoseconds
* Update prompt expansion to pass sub-second times for time formatting
* Update zsh/stat to pass sub-second times for atime/mtime/ctime

Patch heavily based on Oliver's earlier work @ workers/24059

2 files changed, 22 insertions, 46 deletions

diff --git a/Src/Modules/datetime.c b/Src/Modules/datetime.c
index 6e9047bc5..be378b347 100644
--- a/Src/Modules/datetime.c
+++ b/Src/Modules/datetime.c
@@ -180,66 +180,30 @@ getcurrentsecs(UNUSED(Param pm))
 }
 
 static double
-getcurrentrealtime(Param pm)
+getcurrentrealtime(UNUSED(Param pm))
 {
-#ifdef HAVE_CLOCK_GETTIME
     struct timespec now;
-
-    if (clock_gettime(CLOCK_REALTIME, &now) < 0) {
-	zwarn("%s: unable to retrieve time: %e", pm->node.nam, errno);
-	return (double)0.0;
-    }
-
+    zgettime(&now);
     return (double)now.tv_sec + (double)now.tv_nsec * 1e-9;
-#else
-    struct timeval now;
-    struct timezone dummy_tz;
-
-    (void)pm;
-    gettimeofday(&now, &dummy_tz);
-
-    return (double)now.tv_sec + (double)now.tv_usec * 1e-6;
-#endif
 }
 
 static char **
-getcurrenttime(Param pm)
+getcurrenttime(UNUSED(Param pm))
 {
     char **arr;
     char buf[DIGBUFSIZE];
-
-#ifdef HAVE_CLOCK_GETTIME
     struct timespec now;
 
-    if (clock_gettime(CLOCK_REALTIME, &now) < 0) {
-	zwarn("%s: unable to retrieve time: %e", pm->node.nam, errno);
-	return NULL;
-    }
-
-    arr = (char **)zhalloc(3 * sizeof(*arr));
-    sprintf(buf, "%ld", (long)now.tv_sec);
-    arr[0] = dupstring(buf);
-    sprintf(buf, "%ld", now.tv_nsec);
-    arr[1] = dupstring(buf);
-    arr[2] = NULL;
-
-    return arr;
-#else
-    struct timeval now;
-    struct timezone dummy_tz;
-
-    (void)pm;
-    gettimeofday(&now, &dummy_tz);
+    zgettime(&now);
 
     arr = (char **)zhalloc(3 * sizeof(*arr));
     sprintf(buf, "%ld", (long)now.tv_sec);
     arr[0] = dupstring(buf);
-    sprintf(buf, "%ld", (long)now.tv_usec * 1000);
+    sprintf(buf, "%ld", (long)now.tv_nsec);
     arr[1] = dupstring(buf);
     arr[2] = NULL;
 
     return arr;
-#endif
 }
 
 static struct builtin bintab[] = {
diff --git a/Src/Modules/stat.c b/Src/Modules/stat.c
index 66baa1292..50a6a9bb2 100644
--- a/Src/Modules/stat.c
+++ b/Src/Modules/stat.c
@@ -188,7 +188,7 @@ static char *timefmt;
 
 /**/
 static void
-stattimeprint(time_t tim, char *outbuf, int flags)
+stattimeprint(time_t tim, long nsecs, char *outbuf, int flags)
 {
     if (flags & STF_RAW) {
 	sprintf(outbuf, "%ld", (unsigned long)tim);
@@ -199,7 +199,7 @@ stattimeprint(time_t tim, char *outbuf, int flags)
 	char *oend = outbuf + strlen(outbuf);
 	/* Where the heck does "40" come from? */
 	int len = ztrftime(oend, 40, timefmt, (flags & STF_GMT) ? gmtime(&tim) :
-			   localtime(&tim), 0L);
+			   localtime(&tim), nsecs);
 	if (len > 0)
 	    metafy(oend, len, META_NOALLOC);
 	if (flags & STF_RAW)
@@ -291,15 +291,27 @@ statprint(struct stat *sbuf, char *outbuf, char *fname, int iwhich, int flags)
 	break;
 
     case ST_ATIM:
-	stattimeprint(sbuf->st_atime, optr, flags);
+#ifdef GET_ST_ATIME_NSEC
+	stattimeprint(sbuf->st_atime, GET_ST_ATIME_NSEC(*sbuf), optr, flags);
+#else
+	stattimeprint(sbuf->st_atime, 0L, optr, flags);
+#endif
 	break;
 
     case ST_MTIM:
-	stattimeprint(sbuf->st_mtime, optr, flags);
+#ifdef GET_ST_MTIME_NSEC
+	stattimeprint(sbuf->st_mtime, GET_ST_MTIME_NSEC(*sbuf), optr, flags);
+#else
+	stattimeprint(sbuf->st_mtime, 0L, optr, flags);
+#endif
 	break;
 
     case ST_CTIM:
-	stattimeprint(sbuf->st_ctime, optr, flags);
+#ifdef GET_ST_CTIME_NSEC
+	stattimeprint(sbuf->st_ctime, GET_ST_CTIME_NSEC(*sbuf), optr, flags);
+#else
+	stattimeprint(sbuf->st_ctime, 0L, optr, flags);
+#endif
 	break;
 
     case ST_BLKSIZE: