MINOR: lua: txn: add lua function in TXN that returns an array of http headers

This patch adds an LUA binding that returns an array of
HTTP headers. The key is the header name and the value is
the header value.

src/hlua.c

@@ -11,6 +11,7 @@
 #include <types/proxy.h>
 
 #include <proto/arg.h>
+#include <proto/hdr_idx.h>
 #include <proto/payload.h>
 #include <proto/proto_http.h>
 #include <proto/sample.h>
@@ -903,6 +904,65 @@ __LJMP static int hlua_run_sample_fetch(lua_State *L)
 	return 1;
 }
 
+/* This function is an LUA binding. It creates ans returns
+ * an array of HTTP headers. This function does not fails.
+ */
+static int hlua_session_getheaders(lua_State *L)
+{
+	struct hlua_txn *s = MAY_LJMP(hlua_checktxn(L, 1));
+	struct session *sess = s->s;
+	const char *cur_ptr, *cur_next, *p;
+	int old_idx, cur_idx;
+	struct hdr_idx_elem *cur_hdr;
+	const char *hn, *hv;
+	int hnl, hvl;
+
+	/* Create the table. */
+	lua_newtable(L);
+
+	/* Build array of headers. */
+	old_idx = 0;
+	cur_next = sess->req->buf->p + hdr_idx_first_pos(&sess->txn.hdr_idx);
+
+	while (1) {
+		cur_idx = sess->txn.hdr_idx.v[old_idx].next;
+		if (!cur_idx)
+			break;
+		old_idx = cur_idx;
+
+		cur_hdr  = &sess->txn.hdr_idx.v[cur_idx];
+		cur_ptr  = cur_next;
+		cur_next = cur_ptr + cur_hdr->len + cur_hdr->cr + 1;
+
+		/* Now we have one full header at cur_ptr of len cur_hdr->len,
+		 * and the next header starts at cur_next. We'll check
+		 * this header in the list as well as against the default
+		 * rule.
+		 */
+
+		/* look for ': *'. */
+		hn = cur_ptr;
+		for (p = cur_ptr; p < cur_ptr + cur_hdr->len && *p != ':'; p++);
+		if (p >= cur_ptr+cur_hdr->len)
+			continue;
+		hnl = p - hn;
+		p++;
+		while (p < cur_ptr+cur_hdr->len && ( *p == ' ' || *p == '\t' ))
+			p++;
+		if (p >= cur_ptr+cur_hdr->len)
+			continue;
+		hv = p;
+		hvl = cur_ptr+cur_hdr->len-p;
+
+		/* Push values in the table. */
+		lua_pushlstring(L, hn, hnl);
+		lua_pushlstring(L, hv, hvl);
+		lua_settable(L, -3);
+	}
+
+	return 1;
+}
+
 /* This function is used as a calback of a task. It is called by the
  * HAProxy task subsystem when the task is awaked. The LUA runtime can
  * return an E_AGAIN signal, the emmiter of this signal must set a
@@ -1218,6 +1278,7 @@ void hlua_init(void)
 	}
 
 	/* Register Lua functions. */
+	hlua_class_function(gL.T, "get_headers", hlua_session_getheaders);
 	hlua_class_function(gL.T, "set_priv",    hlua_setpriv);
 	hlua_class_function(gL.T, "get_priv",    hlua_getpriv);