Add the .sub() and .suball() methods.

README.rst

@@ -34,6 +34,8 @@ CONTENTS
 * :ref:`func_set.nmatches`
 * :ref:`func_set.re_match`
 * :ref:`func_set.string`
+* :ref:`func_set.sub`
+* :ref:`func_set.suball`
 * :ref:`func_set.which`
 * :ref:`func_version`
 
@@ -262,6 +264,52 @@ Example::
   }
 
 
+.. _func_set.sub:
+
+STRING xset.sub(STRING str, STRING sub, INT n, ENUM select)
+-----------------------------------------------------------
+
+::
+
+      STRING xset.sub(
+            STRING str,
+            STRING sub,
+            INT n=0,
+            ENUM {UNIQUE, EXACT, FIRST, LAST, SHORTEST, LONGEST} select=UNIQUE
+      )
+
+Returns ...
+
+Example::
+
+  if (myset.hasprefix(req.url)) {
+     # ...
+  }
+
+
+.. _func_set.suball:
+
+set.suball(...)
+---------------
+
+::
+
+      STRING xset.suball(
+            STRING str,
+            STRING sub,
+            INT n=0,
+            ENUM {UNIQUE, EXACT, FIRST, LAST, SHORTEST, LONGEST} select=UNIQUE
+      )
+
+Returns ...
+
+Example::
+
+  if (myset.hasprefix(req.url)) {
+     # ...
+  }
+
+
 .. _func_set.debug:
 
 STRING xset.debug()

src/tests/sub.vtc

+# looks like -*- vcl -*-
+
+varnishtest ".sub() and .suball() methods"
+
+# cf. Varnish c00001.vtc, r00251.vtc, r00913.vtc, r00921.vtc.
+varnish v1 -vcl {
+	import ${vmod_selector};
+	backend b { .host = "${bad_ip}"; }
+
+	sub vcl_init {
+		new s = selector.set();
+		s.add("foo", regex="ar");
+		s.add("bar", regex="(b)(a)(r)(f)");
+		s.add("baz", regex="$");
+		s.add("quux", regex=".*");
+		s.add("foobar", regex=":.*");
+	}
+
+	sub vcl_recv {
+		return (synth(200));
+	}
+
+	sub vcl_synth {
+		set resp.http.N-1-1 = s.sub("_barf_", "\0\0", 1);
+		set resp.http.N-1-2
+		    = s.sub("_barf_", resp.http.nosuchheader, 1);
+		set resp.http.N-1-3
+		    = "zoom" + s.sub(resp.http.Foomble, "\0\0", 1) + "box";
+		set resp.http.N-2-1 = s.sub("_barf_", "\4\3\2p", 2);
+		set resp.http.N-2-2 = s.sub("_barf_", "\4\\\3\2p", 2);
+		set resp.http.N-2-3 = s.sub("_barf_", "\4\&\3\2p", 2);
+		set resp.http.N-2-4 = s.sub("_barf_", "\0\4\3\2\\p", 2);
+		set resp.http.N-3 = s.sub(resp.http.bar, "XXX", 3);
+		set resp.http.N-4 = s.sub("/", client.ip, 4);
+		set resp.http.N-5 = s.sub(client.ip, client.ip, 5);
+		return (deliver);
+	}
+} -start
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.status == 200
+	expect resp.http.N-1-1 == "_bararf_"
+	expect resp.http.N-1-2 == "_bf_"
+	expect resp.http.N-1-3 == "zoombox"
+	expect resp.http.N-2-1 == "_frap_"
+	expect resp.http.N-2-2 == "_f\\rap_"
+	expect resp.http.N-2-3 == "_f&rap_"
+	expect resp.http.N-2-4 == "_barffra\\p_"
+	expect resp.http.N-3 == "XXX"
+	expect resp.http.N-4 == "${localhost}"
+	expect resp.http.N-5 == "${localhost}"
+} -run
+
+# cf. Varnish c00047.vtc, r01557.vtc, r01566.vtc
+varnish v1 -vcl {
+	import ${vmod_selector};
+	backend b { .host = "${bad_ip}"; }
+
+	sub vcl_init {
+		new s = selector.set();
+		s.add("1", regex="barb");
+		s.add("2", regex="ar");
+		s.add("3", regex="^");
+		s.add("4", regex="^[;]*");
+		s.add("5", regex="^b*");
+		s.add("6", regex="ping");
+		s.add("7", regex="(?<=[&\?])(foo|bar)=[^&]+(?:&|$)");
+		s.add("8", regex="\??(p|pi)=.*?(&|$)");
+	}
+
+	sub vcl_recv {
+		return (synth(200));
+	}
+
+	sub vcl_synth {
+		set resp.http.N-1 = s.suball("barbar", "zz", 1);
+		set resp.http.N-2 = s.suball("barbar", "zz", 2);
+		set resp.http.N-3 = s.suball("barbar", "baz", 3);
+		set resp.http.N-4 = s.suball("barbar", "baz", 4);
+		set resp.http.N-5-1 = s.suball("bbbar", "b", 5);
+		set resp.http.N-5-2 = s.suball("barbar", "z", 5);
+		set resp.http.N-6 = s.suball("barbar", "pong", 6);
+		set resp.http.N-7 = s.suball("/?foo=0&bar=1&foobar=2", "", 7);
+		return (deliver);
+	}
+}
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.status == 200
+	expect resp.http.N-1 == "zzar"
+	expect resp.http.N-2 == "bzzbzz"
+	expect resp.http.N-3 == "bazbarbar"
+	expect resp.http.N-4 == "bazbarbar"
+	expect resp.http.N-5-1 == "bar"
+	expect resp.http.N-5-2 == "zarbar"
+	expect resp.http.N-6 == "barbar"
+	expect resp.http.N-7 == "/?foobar=2"
+} -run

src/vmod_selector.c

@@ -616,9 +616,10 @@ vmod_set_string(VRT_CTX, struct vmod_selector_set * set, VCL_INT n,
 	return (s);
 }
 
-VCL_BOOL
-vmod_set_re_match(VRT_CTX, struct vmod_selector_set *set, VCL_STRING subject,
-		  VCL_INT n, VCL_ENUM selects)
+static vre_t *
+get_re(VRT_CTX, const struct vmod_selector_set * const restrict set,
+       VCL_INT n, VCL_ENUM const restrict selects,
+       const char * const restrict method)
 {
 	unsigned idx;
 	vre_t *re;
@@ -626,17 +627,56 @@ vmod_set_re_match(VRT_CTX, struct vmod_selector_set *set, VCL_STRING subject,
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
 	CHECK_OBJ_NOTNULL(set, VMOD_SELECTOR_SET_MAGIC);
 
-	idx = get_idx(ctx, n, set, "re_match", selects);
+	idx = get_idx(ctx, n, set, method, selects);
 	if (idx == UINT_MAX)
-		return (0);
-	if (!check_added(ctx, set, idx, REGEX, "re_match", "regex"))
-		return (0);
+		return (NULL);
+	if (!check_added(ctx, set, idx, REGEX, method, "regex"))
+		return (NULL);
 
 	re = set->table[idx]->re;
 	AN(re);
+	return (re);
+}
+
+VCL_BOOL
+vmod_set_re_match(VRT_CTX, struct vmod_selector_set *set, VCL_STRING subject,
+		  VCL_INT n, VCL_ENUM selects)
+{
+	vre_t *re;
+
+	re = get_re(ctx, set, n, selects, "re_match");
+	if (re == NULL)
+		return (0);
 	return (VRT_re_match(ctx, subject, re));
 }
 
+static VCL_STRING
+sub(VRT_CTX, struct vmod_selector_set * const restrict set, int all,
+    VCL_STRING const restrict str, VCL_STRING const restrict sub, VCL_INT n,
+    VCL_ENUM const restrict selects, const char * const restrict method)
+{
+	vre_t *re;
+
+	re = get_re(ctx, set, n, selects, method);
+	if (re == NULL)
+		return (NULL);
+	return (VRT_regsub(ctx, all, str, re, sub));
+}
+
+VCL_STRING
+vmod_set_sub(VRT_CTX, struct vmod_selector_set *set, VCL_STRING str,
+	     VCL_STRING subst, VCL_INT n, VCL_ENUM selects)
+{
+	return (sub(ctx, set, 0, str, subst, n, selects, "sub"));
+}
+
+VCL_STRING
+vmod_set_suball(VRT_CTX, struct vmod_selector_set *set, VCL_STRING str,
+		VCL_STRING subst, VCL_INT n, VCL_ENUM selects)
+{
+	return (sub(ctx, set, 1, str, subst, n, selects, "suball"));
+}
+
 VCL_STRING
 vmod_set_debug(VRT_CTX, struct vmod_selector_set *set)
 {

src/vmod_selector.vcc

@@ -147,6 +147,30 @@ $Method BOOL .re_match(STRING subject, INT n=0,
 
 Returns ...
 
+Example::
+
+  if (myset.hasprefix(req.url)) {
+     # ...
+  }
+
+$Method STRING .sub(STRING str, STRING sub, INT n=0,
+		    ENUM {UNIQUE, EXACT, FIRST, LAST, SHORTEST, LONGEST}
+		    select=UNIQUE)
+
+Returns ...
+
+Example::
+
+  if (myset.hasprefix(req.url)) {
+     # ...
+  }
+
+$Method STRING .suball(STRING str, STRING sub, INT n=0,
+		       ENUM {UNIQUE, EXACT, FIRST, LAST, SHORTEST, LONGEST}
+		       select=UNIQUE)
+
+Returns ...
+
 Example::
 
   if (myset.hasprefix(req.url)) {