Improve the shmlog facilities.

Move the sleeping and timing out into the library so we do not
have to repeat it in all apps.  Should we ever find an app
that needs something else, we will cater for it then.

Add VSL_Dispatch() which calls a (supplied) function (pointer) for each
record.  Additional useful information is passed as arguments, such
as classification (backend/client/other) etc.

Add a default handler for printing a record.

Add VSL_Select() where the application can specify tags that are mandatory
and which should not be subject to -i/-x/-I/-X/-b/-c filtering.

Be more frugal with memory.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@817 d4fa192b-c00b-0410-8231-f00ffab90ce4

include/varnishapi.h

@@ -8,16 +8,21 @@
 #define V_DEAD __attribute__ ((noreturn))
 
 /* shmlog.c */
+typedef int vsl_handler(void *priv, unsigned tag, unsigned fd, unsigned len, unsigned spec, const char *ptr);
+#define VSL_S_CLIENT	(1 << 0)
+#define VSL_S_BACKEND	(1 << 1)
 #define VSL_ARGS	"bcdr:i:x:CI:X:"
+vsl_handler VSL_H_Print;
 struct VSL_data;
 struct VSL_data *VSL_New(void);
+void VSL_Select(struct VSL_data *vd, unsigned tag);
 int VSL_OpenLog(struct VSL_data *vd);
+int VSL_Dispatch(struct VSL_data *vd, vsl_handler *func, void *priv);
 int VSL_NextLog(struct VSL_data *lh, unsigned char **pp);
 int VSL_Arg(struct VSL_data *vd, int arg, const char *opt);
 struct varnish_stats *VSL_OpenStats(void);
 const char *VSL_tags[256];
 
-
 /* varnish_debug.c */
 void		 vdb_panic(const char *, ...) V_DEAD;
 

lib/libvarnishapi/shmlog.c

@@ -11,16 +11,28 @@
 #include <fcntl.h>
 #include <regex.h>
 #include <sys/mman.h>
+#include <assert.h>
 
 #include "shmlog.h"
+#include "miniobj.h"
 #include "varnishapi.h"
 
+/* Parameters */
+#define			SLEEP_USEC	(50*1000)
+#define			TIMEOUT_USEC	(5*1000*1000)
+
+#define NFD		(256 * 256)
+
 struct VSL_data {
+	unsigned		magic;
+#define VSL_MAGIC		0x6e3bd69b
+
 	struct shmloghead	*head;
 	unsigned char		*logstart;
 	unsigned char		*logend;
 	unsigned char		*ptr;
 
+	/* for -r option */
 	FILE			*fi;
 	unsigned char		rbuf[5 + 255 + 1];
 
@@ -28,10 +40,14 @@ struct VSL_data {
 	int			c_opt;
 	int			d_opt;
 
-	int			ix_opt;
-	unsigned char 		supr[256];
+	unsigned		flags;
+#define F_SEEN_IX		(1 << 0)
 
-	unsigned char		dir[65536];
+	unsigned char		map[NFD];
+#define M_CLIENT		(1 << 0)
+#define M_BACKEND		(1 << 1)
+#define M_SUPPRESS		(1 << 2)
+#define M_SELECT		(1 << 3)
 
 	int			regflags;
 	regex_t			*regincl;
@@ -101,16 +117,33 @@ VSL_New(void)
 {
 	struct VSL_data *vd;
 
+	assert(VSL_S_CLIENT == M_CLIENT);
+	assert(VSL_S_BACKEND == M_BACKEND);
 	vd = calloc(sizeof *vd, 1);
+	assert(vd != NULL);
 	vd->regflags = REG_EXTENDED | REG_NOSUB;
+	vd->magic = VSL_MAGIC;
 	return (vd);
 }
 
+/*--------------------------------------------------------------------*/
+
+void
+VSL_Select(struct VSL_data *vd, unsigned tag)
+{
+
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
+	vd->map[tag] |= M_SELECT;
+}
+
+/*--------------------------------------------------------------------*/
+
 int
 VSL_OpenLog(struct VSL_data *vd)
 {
 	unsigned char *p;
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	if (vd->fi != NULL)
 		return (0);
 
@@ -122,12 +155,6 @@ VSL_OpenLog(struct VSL_data *vd)
 	vd->logend = vd->logstart + vsl_lh->size;
 	vd->ptr = vd->logstart;
 
-	if (vd->b_opt)
-		memset(vd->dir, 1, sizeof vd->dir);
-
-	if (vd->c_opt)
-		memset(vd->dir, 2, sizeof vd->dir);
-
 	if (!vd->d_opt)
 		while (vsl_nextlog(vd, &p) == 1)
 			continue;
@@ -140,8 +167,10 @@ static int
 vsl_nextlog(struct VSL_data *vd, unsigned char **pp)
 {
 	unsigned char *p;
+	unsigned w;
 	int i;
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	if (vd->fi != NULL) {
 		i = fread(vd->rbuf, 4, 1, vd->fi);
 		if (i != 1)
@@ -154,19 +183,22 @@ vsl_nextlog(struct VSL_data *vd, unsigned char **pp)
 	}
 
 	p = vd->ptr;
-	while (1) {
+	for (w = 0; w < TIMEOUT_USEC;) {
 		if (*p == SLT_WRAPMARKER) {
 			p = vd->logstart;
 			continue;
 		}
 		if (*p == SLT_ENDMARKER) {
-			vd->ptr = p;
-			return (0);
+			w += SLEEP_USEC;
+			usleep(SLEEP_USEC);
+			continue;
 		}
 		vd->ptr = p + p[1] + 5;
 		*pp = p;
 		return (1);
 	}
+	vd->ptr = p;
+	return (0);
 }
 
 int
@@ -177,6 +209,7 @@ VSL_NextLog(struct VSL_data *vd, unsigned char **pp)
 	unsigned u;
 	int i;
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	while (1) {
 		i = vsl_nextlog(vd, &p);
 		if (i != 1)
@@ -184,19 +217,25 @@ VSL_NextLog(struct VSL_data *vd, unsigned char **pp)
 		u = (p[2] << 8) | p[3];
 		switch(p[0]) {
 		case SLT_SessionOpen:
-			vd->dir[u] = 1;
+			vd->map[u] |= M_CLIENT;
+			vd->map[u] &= ~M_BACKEND;
 			break;
 		case SLT_BackendOpen:
-			vd->dir[u] = 2;
+			vd->map[u] |= M_BACKEND;
+			vd->map[u] &= ~M_CLIENT;
 			break;
 		default:
 			break;
 		}
-		if (vd->supr[p[0]]) 
+		if (vd->map[p[0]] & M_SELECT) {
+			*pp = p;
+			return (1);
+		}
+		if (vd->map[p[0]] & M_SUPPRESS) 
 			continue;
-		if (vd->b_opt && vd->dir[u] == 1)
+		if (vd->b_opt && !(vd->map[u] & M_BACKEND))
 			continue;
-		if (vd->c_opt && vd->dir[u] == 2)
+		if (vd->c_opt && !(vd->map[u] & M_CLIENT))
 			continue;
 		if (vd->regincl != NULL) {
 			rm.rm_so = 0;
@@ -219,10 +258,51 @@ VSL_NextLog(struct VSL_data *vd, unsigned char **pp)
 
 /*--------------------------------------------------------------------*/
 
+int
+VSL_Dispatch(struct VSL_data *vd, vsl_handler *func, void *priv)
+{
+	int i;
+	unsigned u;
+	unsigned char *p;
+
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
+	while (1) {
+		i = VSL_NextLog(vd, &p);
+		if (i <= 0)
+			return (i);
+		u = (p[2] << 8) | p[3];
+		if (func(priv,
+		    p[0], u, p[1],
+		    vd->map[u] & (VSL_S_CLIENT|VSL_S_BACKEND),
+		    p + 4))
+			return (1);
+	}
+}
+
+/*--------------------------------------------------------------------*/
+
+int
+VSL_H_Print(void *priv, unsigned tag, unsigned fd, unsigned len, unsigned spec, const char *ptr)
+{
+	FILE *fo = priv;
+
+	assert(fo != NULL);
+	if (tag == SLT_Debug) {
+	}
+	fprintf(fo, "%5d %-12s %c %.*s\n",
+	    fd, VSL_tags[tag],
+	    ((spec & VSL_S_CLIENT) ? 'c' : (spec & VSL_S_BACKEND) ? 'b' : ' '),
+	    len, ptr);
+	return (0);
+}
+
+/*--------------------------------------------------------------------*/
+
 static int
 vsl_r_arg(struct VSL_data *vd, const char *opt)
 {
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	if (!strcmp(opt, "-"))
 		vd->fi = stdin;
 	else
@@ -242,6 +322,7 @@ vsl_IX_arg(struct VSL_data *vd, const char *opt, int arg)
 	regex_t **rp;
 	char buf[BUFSIZ];
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	if (arg == 'I')
 		rp = &vd->regincl;
 	else
@@ -272,11 +353,12 @@ vsl_ix_arg(struct VSL_data *vd, const char *opt, int arg)
 	int i, j, l;
 	const char *b, *e, *p, *q;
 
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	/* If first option is 'i', set all bits for supression */
-	if (arg == 'i' && vd->ix_opt == 0)
+	if (arg == 'i' && !(vd->flags & F_SEEN_IX))
 		for (i = 0; i < 256; i++)
-			vd->supr[i] = 1;
-	vd->ix_opt = 1;
+			vd->map[i] |= M_SUPPRESS;
+	vd->flags |= F_SEEN_IX;
 
 	for (b = opt; *b; b = e) {
 		while (isspace(*b))
@@ -301,9 +383,9 @@ vsl_ix_arg(struct VSL_data *vd, const char *opt, int arg)
 				continue;
 
 			if (arg == 'x')
-				vd->supr[i] = 1;
+				vd->map[i] |= M_SUPPRESS;
 			else
-				vd->supr[i] = 0;
+				vd->map[i] &= ~M_SUPPRESS;
 			break;
 		}
 		if (i == 256) {
@@ -320,6 +402,8 @@ vsl_ix_arg(struct VSL_data *vd, const char *opt, int arg)
 int
 VSL_Arg(struct VSL_data *vd, int arg, const char *opt)
 {
+
+	CHECK_OBJ_NOTNULL(vd, VSL_MAGIC);
 	switch (arg) {
 	case 'b': vd->b_opt = !vd->b_opt; return (1);
 	case 'c': vd->c_opt = !vd->c_opt; return (1);