Add support for removing HTTP header lines:

	sub vcl_deliver {
		remove resp.http.etag ;
		remove resp.http.server ;
	}



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@1645 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache.h

@@ -427,6 +427,7 @@ int http_DissectRequest(struct worker *w, struct http *sp, int fd);
 int http_DissectResponse(struct worker *w, struct http *sp, int fd);
 void http_DoConnection(struct sess *sp);
 void http_CopyHome(struct worker *w, int fd, struct http *hp);
+void http_Unset(struct http *hp, const char *hdr);
 
 
 #define HTTPH(a, b, c, d, e, f, g) extern char b[];

bin/varnishd/cache_http.c

@@ -176,7 +176,7 @@ http_Setup(struct http *hp, void *space, unsigned len)
 
 
 static int
-http_IsHdr(struct http_hdr *hh, char *hdr)
+http_IsHdr(struct http_hdr *hh, const char *hdr)
 {
 	unsigned l;
 
@@ -948,6 +948,22 @@ http_PrintfHeader(struct worker *w, int fd, struct http *to, const char *fmt, ..
 		to->nhd++;
 	}
 }
+/*--------------------------------------------------------------------*/
+
+void
+http_Unset(struct http *hp, const char *hdr)
+{
+	unsigned u, v;
+
+	for (v = u = HTTP_HDR_FIRST; u < hp->nhd; u++) {
+		if (http_IsHdr(&hp->hd[u], hdr)) 
+			continue;
+		if (v != u)
+			memcpy(&hp->hd[v], &hp->hd[u], sizeof hp->hd[v]);
+		v++;
+	}
+	hp->nhd = v;
+}
 
 /*--------------------------------------------------------------------*/
 

bin/varnishd/cache_vrt.c

@@ -36,6 +36,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdarg.h>
 
 #include "shmlog.h"
 #include "heritage.h"
@@ -70,10 +71,9 @@ VRT_count(struct sess *sp, unsigned u)
 
 /*--------------------------------------------------------------------*/
 
-char *
-VRT_GetHdr(struct sess *sp, enum gethdr_e where, const char *n)
+static struct http *
+vrt_selecthttp(struct sess *sp, enum gethdr_e where)
 {
-	char *p;
 	struct http *hp;
 
 	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
@@ -94,6 +94,17 @@ VRT_GetHdr(struct sess *sp, enum gethdr_e where, const char *n)
 		INCOMPL();
 	}
 	CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
+	return (hp);
+}
+
+char *
+VRT_GetHdr(struct sess *sp, enum gethdr_e where, const char *n)
+{
+	char *p;
+	struct http *hp;
+
+	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
+	hp = vrt_selecthttp(sp, where);
 	if (!http_GetHdr(hp, n, &p))
 		return (NULL);
 	return (p);
@@ -101,6 +112,27 @@ VRT_GetHdr(struct sess *sp, enum gethdr_e where, const char *n)
 
 /*--------------------------------------------------------------------*/
 
+void
+VRT_SetHdr(struct sess *sp , enum gethdr_e where, const char *hdr, ...)
+{
+	struct http *hp;
+	va_list ap;
+	const char *p;
+
+	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
+	hp = vrt_selecthttp(sp, where);
+	va_start(ap, hdr);
+	p = va_arg(ap, const char *);
+	if (p == NULL) {
+		http_Unset(hp, hdr);
+	} else {
+		INCOMPL();
+	}
+	va_end(ap);
+}
+
+/*--------------------------------------------------------------------*/
+
 void
 VRT_handling(struct sess *sp, unsigned hand)
 {

include/vrt.h

@@ -76,6 +76,7 @@ int VRT_switch_config(const char *);
 
 enum gethdr_e { HDR_REQ, HDR_RESP, HDR_OBJ, HDR_BEREQ };
 char *VRT_GetHdr(struct sess *, enum gethdr_e where, const char *);
+void VRT_SetHdr(struct sess *, enum gethdr_e where, const char *, ...);
 void VRT_handling(struct sess *sp, unsigned hand);
 
 /* Backend related */

lib/libvcl/vcc_action.c

@@ -103,6 +103,16 @@ illegal_assignment(struct tokenlist *tl, const char *type)
 	    " only '=' is legal for %s\n", type);
 }
 
+static void
+check_writebit(struct tokenlist *tl, struct var *vp)
+{
+
+	if (vp->access == V_RW || vp->access == V_WO)
+		return;
+	vsb_printf(tl->sb, "Variable %.*s cannot be modified.\n", PF(tl->t));
+	vcc_ErrWhere(tl, tl->t);
+}
+
 static void
 parse_set(struct tokenlist *tl)
 {
@@ -115,12 +125,8 @@ parse_set(struct tokenlist *tl)
 	vp = vcc_FindVar(tl, tl->t, vcc_vars);
 	ERRCHK(tl);
 	assert(vp != NULL);
-	if (vp->access != V_RW && vp->access != V_WO) {
-		vsb_printf(tl->sb, "Variable %.*s cannot be written.\n",
-		    PF(vt));
-		vcc_ErrWhere(tl, vt);
-		return;
-	}
+	check_writebit(tl, vp);
+	ERRCHK(tl);
 	Fb(tl, 1, "%s", vp->lname);
 	vcc_NextToken(tl);
 	switch (vp->fmt) {
@@ -215,6 +221,31 @@ parse_set(struct tokenlist *tl)
 
 /*--------------------------------------------------------------------*/
 
+static void
+parse_remove(struct tokenlist *tl)
+{
+	struct var *vp;
+	struct token *vt;
+
+	vcc_NextToken(tl);
+	ExpectErr(tl, VAR);
+	vt = tl->t;
+	vp = vcc_FindVar(tl, tl->t, vcc_vars);
+	if (vp->fmt != STRING) {
+		vsb_printf(tl->sb,
+		    "Only STRING variables can be removed.\n");
+		vcc_ErrWhere(tl, tl->t);
+		return;
+	}
+	check_writebit(tl, vp);
+	ERRCHK(tl);
+	Fb(tl, 1, "%s, 0);\n", vp->lname);
+	vcc_NextToken(tl);
+	ExpectErr(tl, ';');
+}
+
+/*--------------------------------------------------------------------*/
+
 typedef void action_f(struct tokenlist *tl);
 
 static struct action_table {
@@ -228,6 +259,7 @@ static struct action_table {
 #undef VCL_RET_MAC_E
 	{ "call", 	parse_call },
 	{ "set", 	parse_set },
+	{ "remove", 	parse_remove },
 	{ NULL,		NULL }
 };
 

lib/libvcl/vcc_fixed_token.c

@@ -432,6 +432,7 @@ vcl_output_lang_h(struct vsb *sb)
 	vsb_cat(sb, "\n");
 	vsb_cat(sb, "enum gethdr_e { HDR_REQ, HDR_RESP, HDR_OBJ, HDR_BEREQ };\n");
 	vsb_cat(sb, "char *VRT_GetHdr(struct sess *, enum gethdr_e where, const char *);\n");
+	vsb_cat(sb, "void VRT_SetHdr(struct sess *, enum gethdr_e where, const char *, ...);\n");
 	vsb_cat(sb, "void VRT_handling(struct sess *sp, unsigned hand);\n");
 	vsb_cat(sb, "\n");
 	vsb_cat(sb, "/* Backend related */\n");

lib/libvcl/vcc_var.c

@@ -108,7 +108,7 @@ HeaderVar(struct tokenlist *tl, const struct token *t, const struct var *vh)
 	    (unsigned)(strlen(v->name + vh->len) + 1), v->name + vh->len);
 	AN(p);
 	v->rname = p;
-	asprintf(&p, "VRT_SetHdr(sp, %s, \"\\%03o%s:\")", wh,
+	asprintf(&p, "VRT_SetHdr(sp, %s, \"\\%03o%s:\"", wh,
 	    (unsigned)(strlen(v->name + vh->len) + 1), v->name + vh->len);
 	AN(p);
 	v->lname = p;