varnishlog -k argument

Implement -k argument in vut for use with varnishlog. This takes as an
argument the number of log transactions to be processed before
exiting. Useful to stop varnishlog after a given set of log data has
been produced.

Drop -s from the 'not implemented yet' list as this option has very
limited usefullness.

bin/varnishlog/varnishlog_options.h

@@ -59,6 +59,7 @@ VUT_OPT_D
 VUT_OPT_g
 VUT_OPT_h
 VSL_OPT_i
+VUT_OPT_k
 VSL_OPT_I
 VSL_OPT_L
 VUT_OPT_n

doc/sphinx/reference/varnishlog.rst

@@ -21,20 +21,6 @@ The following options are available:
 
 .. include:: ../include/varnishlog_options.rst
 
--k num
-
-	Only show the first num log transactions (or log records
-	in -g raw mode)
-
-	XXX: Not yet implemented
-
--s num
-
-	Skip the first num log transactions (or log records if
-	in -g raw mode)
-
-	XXX: Not yet implemented
-
 SIGNALS
 =======
 

include/vut.h

@@ -41,6 +41,7 @@ struct VUT {
 	int		d_opt;
 	int		D_opt;
 	int		g_arg;
+	int		k_arg;
 	char		*P_arg;
 	char		*q_arg;
 	char		*r_arg;

include/vut_options.h

@@ -51,6 +51,12 @@
 	    "Print program usage and exit"				\
 	)
 
+#define VUT_OPT_k							\
+	VOPT("k:", "[-k num]", "Limit transactions",			\
+	    "Process this number of matching log transactions before"	\
+	    " exiting."							\
+	)
+
 #define VUT_OPT_n							\
 	VOPT("n:", "[-n name]", "Varnish instance name",		\
 	    "Specify the name of the varnishd instance to get logs"	\

lib/libvarnishtools/vut.c

@@ -83,6 +83,24 @@ vut_sigusr1(int sig)
 	VUT.sigusr1 = 1;
 }
 
+static int __match_proto__(VSLQ_dispatch_f)
+vut_dispatch(struct VSL_data *vsl, struct VSL_transaction * const trans[],
+    void *priv)
+{
+	int i;
+
+	(void)priv;
+	if (VUT.k_arg == 0)
+		return (-1);	/* End of file */
+	AN(VUT.dispatch_f);
+	i = VUT.dispatch_f(vsl, trans, VUT.dispatch_priv);
+	if (VUT.k_arg > 0)
+		VUT.k_arg--;
+	if (i >= 0 && VUT.k_arg == 0)
+		return (-1);	/* End of file */
+	return (i);
+}
+
 void
 VUT_Error(int status, const char *fmt, ...)
 {
@@ -114,6 +132,7 @@ int
 VUT_Arg(int opt, const char *arg)
 {
 	int i;
+	char *p;
 
 	switch (opt) {
 	case 'd':
@@ -127,6 +146,12 @@ VUT_Arg(int opt, const char *arg)
 	case 'g':
 		/* Grouping */
 		return (VUT_g_Arg(arg));
+	case 'k':
+		/* Log transaction limit */
+		VUT.k_arg = (int)strtol(arg, &p, 10);
+		if (*p != '\0' || VUT.k_arg <= 0)
+			VUT_Error(1, "-k: Invalid number '%s'", arg);
+		return (1);
 	case 'n':
 		/* Varnish instance */
 		if (VUT.vsm == NULL)
@@ -178,6 +203,7 @@ VUT_Init(const char *progname)
 	AZ(VUT.vsl);
 	VUT.vsl = VSL_New();
 	AN(VUT.vsl);
+	VUT.k_arg = -1;
 }
 
 void
@@ -281,8 +307,7 @@ VUT_Main(void)
 			/* Flush and report any incomplete records */
 			VUT.sigusr1 = 0;
 			if (VUT.vslq != NULL)
-				VSLQ_Flush(VUT.vslq, VUT.dispatch_f,
-				    VUT.dispatch_priv);
+				VSLQ_Flush(VUT.vslq, vut_dispatch, NULL);
 		}
 
 		if (VUT.vslq == NULL) {
@@ -307,7 +332,7 @@ VUT_Main(void)
 			VUT_Error(0, "Log reacquired");
 		}
 
-		i = VSLQ_Dispatch(VUT.vslq, VUT.dispatch_f, VUT.dispatch_priv);
+		i = VSLQ_Dispatch(VUT.vslq, vut_dispatch, NULL);
 		if (i == 1)
 			/* Call again */
 			continue;
@@ -330,7 +355,7 @@ VUT_Main(void)
 
 		/* XXX: Make continuation optional */
 
-		VSLQ_Flush(VUT.vslq, VUT.dispatch_f, VUT.dispatch_priv);
+		VSLQ_Flush(VUT.vslq, vut_dispatch, NULL);
 		VSLQ_Delete(&VUT.vslq);
 		AZ(VUT.vslq);