[git commit] watch: support fractional -n SEC

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=0ddc742c04538fdd8be51fb1d4dbcbd4309952db
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master

function                                             old     new   delta
watch_main                                           212     232     +20

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 include/libbb.h |  2 ++
 procps/watch.c  | 17 ++++++++++++-----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/include/libbb.h b/include/libbb.h
index 3366df30f..7a1e13875 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1040,9 +1040,11 @@ uint16_t xatou16(const char *numstr) FAST_FUNC;
 #if ENABLE_FLOAT_DURATION
 typedef double duration_t;
 void sleep_for_duration(duration_t duration) FAST_FUNC;
+#define DURATION_FMT "f"
 #else
 typedef unsigned duration_t;
 #define sleep_for_duration(duration) sleep(duration)
+#define DURATION_FMT "u"
 #endif
 duration_t parse_duration_str(char *str) FAST_FUNC;
 
diff --git a/procps/watch.c b/procps/watch.c
index dbe427aad..059eb1dda 100644
--- a/procps/watch.c
+++ b/procps/watch.c
@@ -22,7 +22,7 @@
 //usage:       "[-n SEC] [-t] PROG ARGS"
 //usage:#define watch_full_usage "\n\n"
 //usage:       "Run PROG periodically\n"
-//usage:     "\n	-n	Loop period in seconds (default 2)"
+//usage:     "\n	-n SEC	Loop period (default 2)"
 //usage:     "\n	-t	Don't print header"
 //usage:
 //usage:#define watch_example_usage
@@ -51,8 +51,9 @@
 int watch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int watch_main(int argc UNUSED_PARAM, char **argv)
 {
+	duration_t period;
+	char *period_str = (char*) "2";
 	unsigned opt;
-	unsigned period = 2;
 	unsigned width, new_width;
 	char *header;
 	char *cmd;
@@ -65,7 +66,7 @@ int watch_main(int argc UNUSED_PARAM, char **argv)
 
 	// "+": stop at first non-option (procps 3.x only); -n NUM
 	// at least one param
-	opt = getopt32(argv, "^+" "dtn:+" "\0" "-1", &period);
+	opt = getopt32(argv, "^+" "dtn:" "\0" "-1", &period_str);
 	argv += optind;
 
 	// watch from both procps 2.x and 3.x does concatenation. Example:
@@ -74,6 +75,7 @@ int watch_main(int argc UNUSED_PARAM, char **argv)
 	while (*++argv)
 		cmd = xasprintf("%s %s", cmd, *argv); // leaks cmd
 
+	period = parse_duration_str(period_str);
 	width = (unsigned)-1; // make sure first time new_width != width
 	header = NULL;
 	while (1) {
@@ -88,7 +90,12 @@ int watch_main(int argc UNUSED_PARAM, char **argv)
 			if (new_width != width) {
 				width = new_width;
 				free(header);
-				header = xasprintf("Every %us: %-*s", period, (int)width, cmd);
+				header = xasprintf("Every"
+					" %"IF_FLOAT_DURATION(".1")DURATION_FMT"s:"
+					" %-*s",
+					period,
+					(int)width, cmd
+				);
 			}
 			if (time_len < width) {
 				strftime_YYYYMMDDHHMMSS(
@@ -106,7 +113,7 @@ int watch_main(int argc UNUSED_PARAM, char **argv)
 		// and does not allow it to overflow the screen
 		// (taking into account linewrap!)
 		system(cmd);
-		sleep(period);
+		sleep_for_duration(period);
 	}
 	return 0; // gcc thinks we can reach this :)
 }