[master] dd16b6d0c Add VRT_UnsetHdr() and remove vrt_magic_string_unset

[Poul-Henning Kamp]

commit dd16b6d0c54e13093acc29652b9e3e5a237c1115
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Thu Aug 19 06:29:09 2021 +0000

    Add VRT_UnsetHdr() and remove vrt_magic_string_unset

diff --git a/bin/varnishd/cache/cache_vrt.c b/bin/varnishd/cache/cache_vrt.c
index 8d8ab859b..17e406edf 100644
--- a/bin/varnishd/cache/cache_vrt.c
+++ b/bin/varnishd/cache/cache_vrt.c
@@ -55,7 +55,6 @@
 #include "proxy/cache_proxy.h"
 
 const void * const vrt_magic_string_end = &vrt_magic_string_end;
-const void * const vrt_magic_string_unset = &vrt_magic_string_unset;
 const struct strands *vrt_null_strands = &(struct strands){
 	.n = 0,
 	.p = (const char *[1]){NULL}
@@ -691,6 +690,19 @@ VRT_ValidHdr(VRT_CTX, VCL_STRANDS s)
 }
 /*--------------------------------------------------------------------*/
 
+VCL_VOID
+VRT_UnsetHdr(VRT_CTX , VCL_HEADER hs)
+{
+	VCL_HTTP hp;
+
+	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
+	AN(hs);
+	AN(hs->what);
+	hp = VRT_selecthttp(ctx, hs->where);
+	CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
+	http_Unset(hp, hs->what);
+}
+
 VCL_VOID
 VRT_SetHdr(VRT_CTX , VCL_HEADER hs, const char *p, ...)
 {
@@ -703,23 +715,19 @@ VRT_SetHdr(VRT_CTX , VCL_HEADER hs, const char *p, ...)
 	AN(hs->what);
 	hp = VRT_selecthttp(ctx, hs->where);
 	CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
-	if (p == vrt_magic_string_unset) {
-		http_Unset(hp, hs->what);
-	} else {
-		va_start(ap, p);
-		b = VRT_String(hp->ws, hs->what + 1, p, ap);
-		va_end(ap);
-		if (b == NULL) {
-			VSLb(ctx->vsl, SLT_LostHeader, "%s", hs->what + 1);
-			return;
-		}
-		if (FEATURE(FEATURE_VALIDATE_HEADERS) && ! validhdr(b)) {
-			VRT_fail(ctx, "Bad header %s", b);
-			return;
-		}
-		http_Unset(hp, hs->what);
-		http_SetHeader(hp, b);
+	va_start(ap, p);
+	b = VRT_String(hp->ws, hs->what + 1, p, ap);
+	va_end(ap);
+	if (b == NULL) {
+		VSLb(ctx->vsl, SLT_LostHeader, "%s", hs->what + 1);
+		return;
+	}
+	if (FEATURE(FEATURE_VALIDATE_HEADERS) && ! validhdr(b)) {
+		VRT_fail(ctx, "Bad header %s", b);
+		return;
 	}
+	http_Unset(hp, hs->what);
+	http_SetHeader(hp, b);
 }
 
 /*--------------------------------------------------------------------*/
diff --git a/include/vrt.h b/include/vrt.h
index 4019f7e57..8c6678935 100644
--- a/include/vrt.h
+++ b/include/vrt.h
@@ -54,6 +54,8 @@
  * binary/load-time compatible, increment MAJOR version
  *
  * NEXT (2021-09-15)
+ *	VRT_UnsetHdr() added
+ *	vrt_magic_string_unset removed (use VRT_UnsetHdr() instead)
  *	VNUMpfx() removed, SF_Parse_{Integer|Decimal|Number} added
  *	vrt_null_strands added
  *	vrt_null_blob added
@@ -593,6 +595,7 @@ VCL_VOID VRT_synth(VRT_CTX, VCL_INT, VCL_STRING);
 VCL_VOID VRT_hit_for_pass(VRT_CTX, VCL_DURATION);
 
 VCL_BOOL VRT_ValidHdr(VRT_CTX, VCL_STRANDS);
+VCL_VOID VRT_UnsetHdr(VRT_CTX, VCL_HEADER);
 VCL_VOID VRT_SetHdr(VRT_CTX, VCL_HEADER, const char *, ...);
 VCL_VOID VRT_handling(VRT_CTX, unsigned hand);
 unsigned VRT_handled(VRT_CTX);
@@ -709,5 +712,4 @@ void VRT_VCL_Allow_Discard(struct vclref **);
 
 VCL_VOID VRT_synth_page(VRT_CTX, VCL_STRANDS);
 extern const void * const vrt_magic_string_end;
-extern const void * const vrt_magic_string_unset;
 int VRT_Stv(const char *nm);
diff --git a/lib/libvcc/vcc_var.c b/lib/libvcc/vcc_var.c
index c71831bd6..286949e49 100644
--- a/lib/libvcc/vcc_var.c
+++ b/lib/libvcc/vcc_var.c
@@ -93,8 +93,7 @@ vcc_Var_Wildcard(struct vcc *tl, struct symbol *parent, struct symbol *sym)
 	AZ(VSB_finish(vsb));
 	sym->lname = TlDup(tl, VSB_data(vsb));
 	VSB_clear(vsb);
-	VSB_printf(vsb, "VRT_SetHdr(ctx, %s, vrt_magic_string_unset)",
-	    sym->rname);
+	VSB_printf(vsb, "VRT_UnsetHdr(ctx, %s)", sym->rname);
 	AZ(VSB_finish(vsb));
 	sym->uname = TlDup(tl, VSB_data(vsb));
 	VSB_destroy(&vsb);