- markus@cvs.openbsd.org 2003/01/23 14:01:53

     [scp.c]
     bandwidth limitation patch (scp -l) from niels@; ok todd@, deraadt@

1 files changed, 76 insertions, 4 deletions

diff --git a/scp.c b/scp.c
index 616dd378..ae0a1ead 100644
--- a/scp.c
+++ b/scp.c
@@ -75,7 +75,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: scp.c,v 1.98 2003/01/10 10:29:35 djm Exp $");
+RCSID("$OpenBSD: scp.c,v 1.99 2003/01/23 14:01:53 markus Exp $");
 
 #include "xmalloc.h"
 #include "atomicio.h"
@@ -90,9 +90,14 @@ extern char *__progname;
 char *__progname;
 #endif
 
+void bwlimit(int);
+
 /* Struct for addargs */
 arglist args;
 
+/* Bandwidth limit */
+off_t limit = 0;
+
 /* Name of current file being transferred. */
 char *curfile;
 
@@ -206,7 +211,8 @@ main(argc, argv)
 	char *argv[];
 {
 	int ch, fflag, tflag, status;
-	char *targ;
+	double speed;
+	char *targ, *endp;
 	extern char *optarg;
 	extern int optind;
 
@@ -219,7 +225,7 @@ main(argc, argv)
 	addargs(&args, "-oClearAllForwardings yes");
 
 	fflag = tflag = 0;
-	while ((ch = getopt(argc, argv, "dfprtvBCc:i:P:q46S:o:F:")) != -1)
+	while ((ch = getopt(argc, argv, "dfl:prtvBCc:i:P:q46S:o:F:")) != -1)
 		switch (ch) {
 		/* User-visible flags. */
 		case '4':
@@ -239,6 +245,12 @@ main(argc, argv)
 		case 'B':
 			addargs(&args, "-oBatchmode yes");
 			break;
+		case 'l':
+			speed = strtod(optarg, &endp);
+			if (speed <= 0 || *endp != '\0')
+				usage();
+			limit = speed * 1024;
+			break;
 		case 'p':
 			pflag = 1;
 			break;
@@ -578,6 +590,8 @@ next:			(void) close(fd);
 					haderr = result >= 0 ? EIO : errno;
 				statbytes += result;
 			}
+			if (limit)
+				bwlimit(amt);
 		}
 		if (showprogress)
 			stop_progress_meter();
@@ -648,6 +662,60 @@ rsource(name, statp)
 }
 
 void
+bwlimit(int amount)
+{
+	static struct timeval bwstart, bwend;
+	static int lamt, thresh = 16384;
+	u_int64_t wait;
+	struct timespec ts, rm;
+
+	if (!timerisset(&bwstart)) {
+		gettimeofday(&bwstart, NULL);
+		return;
+	}
+
+	lamt += amount;
+	if (lamt < thresh)
+		return;
+
+	gettimeofday(&bwend, NULL);
+	timersub(&bwend, &bwstart, &bwend);
+	if (!timerisset(&bwend))
+		return;
+
+	lamt *= 8;
+	wait = (double)1000000L * lamt / limit;
+
+	bwstart.tv_sec = wait / 1000000L;
+	bwstart.tv_usec = wait % 1000000L;
+
+	if (timercmp(&bwstart, &bwend, >)) {
+		timersub(&bwstart, &bwend, &bwend);
+
+		/* Adjust the wait time */
+		if (bwend.tv_sec) {
+			thresh /= 2;
+			if (thresh < 2048)
+				thresh = 2048;
+		} else if (bwend.tv_usec < 100) {
+			thresh *= 2;
+			if (thresh > 32768)
+				thresh = 32768;
+		}
+
+		TIMEVAL_TO_TIMESPEC(&bwend, &ts);
+		while (nanosleep(&ts, &rm) == -1) {
+			if (errno != EINTR)
+				break;
+			ts = rm;
+		}
+	}
+
+	lamt = 0;
+	gettimeofday(&bwstart, NULL);
+}
+
+void
 sink(argc, argv)
 	int argc;
 	char *argv[];
@@ -844,6 +912,10 @@ bad:			run_err("%s: %s", np, strerror(errno));
 				cp += j;
 				statbytes += j;
 			} while (amt > 0);
+		
+			if (limit)
+				bwlimit(4096);
+
 			if (count == bp->cnt) {
 				/* Keep reading so we stay sync'd up. */
 				if (wrerr == NO) {
@@ -954,7 +1026,7 @@ usage(void)
 {
 	(void) fprintf(stderr,
 	    "usage: scp [-pqrvBC46] [-F config] [-S program] [-P port]\n"
-	    "           [-c cipher] [-i identity] [-o option]\n"
+	    "           [-c cipher] [-i identity] [-l limit] [-o option]\n"
 	    "           [[user@]host1:]file1 [...] [[user@]host2:]file2\n");
 	exit(1);
 }