1 files changed, 75 insertions, 0 deletions
diff --git a/release/src/router/busybox/procps/watch.c b/release/src/router/busybox/procps/watch.c
new file mode 100644
index 00000000..5fd05107
--- /dev/null
+++ b/release/src/router/busybox/procps/watch.c
@@ -0,0 +1,75 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini watch implementation for busybox
+ *
+ * Copyright (C) 2001 by Michael Habermann <mhabermann@gmx.de>
+ * Copyrigjt (C) Mar 16, 2003 Manuel Novoa III   (mjn3@codepoet.org)
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+/* BB_AUDIT SUSv3 N/A */
+/* BB_AUDIT GNU defects -- only option -n is supported. */
+
+#include "libbb.h"
+
+// procps 2.0.18:
+// watch [-d] [-n seconds]
+//   [--differences[=cumulative]] [--interval=seconds] command
+//
+// procps-3.2.3:
+// watch [-dt] [-n seconds]
+//   [--differences[=cumulative]] [--interval=seconds] [--no-title] command
+//
+// (procps 3.x and procps 2.x are forks, not newer/older versions of the same)
+
+int watch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int watch_main(int argc UNUSED_PARAM, char **argv)
+{
+	unsigned opt;
+	unsigned period = 2;
+	unsigned width, new_width;
+	char *header;
+	char *cmd;
+
+	opt_complementary = "-1:n+"; // at least one param; -n NUM
+	// "+": stop at first non-option (procps 3.x only)
+	opt = getopt32(argv, "+dtn:", &period);
+	argv += optind;
+
+	// watch from both procps 2.x and 3.x does concatenation. Example:
+	// watch ls -l "a /tmp" "2>&1" -- ls won't see "a /tmp" as one param
+	cmd = *argv;
+	while (*++argv)
+		cmd = xasprintf("%s %s", cmd, *argv); // leaks cmd
+
+	width = (unsigned)-1; // make sure first time new_width != width
+	header = NULL;
+	while (1) {
+		printf("\033[H\033[J");
+		if (!(opt & 0x2)) { // no -t
+			const unsigned time_len = sizeof("1234-67-90 23:56:89");
+			time_t t;
+
+			get_terminal_width_height(STDIN_FILENO, &new_width, NULL);
+			if (new_width != width) {
+				width = new_width;
+				free(header);
+				header = xasprintf("Every %us: %-*s", period, (int)width, cmd);
+			}
+			time(&t);
+			if (time_len < width)
+				strftime(header + width - time_len, time_len,
+					"%Y-%m-%d %H:%M:%S", localtime(&t));
+
+			puts(header);
+		}
+		fflush(stdout);
+		// TODO: 'real' watch pipes cmd's output to itself
+		// and does not allow it to overflow the screen
+		// (taking into account linewrap!)
+		system(cmd);
+		sleep(period);
+	}
+	return 0; // gcc thinks we can reach this :)
+}