1 files changed, 95 insertions, 0 deletions
diff --git a/src/core/lib/gpr/host_port.cc b/src/core/lib/gpr/host_port.cc
new file mode 100644
index 0000000000..29178279d3
--- /dev/null
+++ b/src/core/lib/gpr/host_port.cc
@@ -0,0 +1,95 @@
+/*
+ *
+ * Copyright 2015 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/host_port.h>
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include "src/core/lib/gpr/string.h"
+
+int gpr_join_host_port(char** out, const char* host, int port) {
+  if (host[0] != '[' && strchr(host, ':') != nullptr) {
+    /* IPv6 literals must be enclosed in brackets. */
+    return gpr_asprintf(out, "[%s]:%d", host, port);
+  } else {
+    /* Ordinary non-bracketed host:port. */
+    return gpr_asprintf(out, "%s:%d", host, port);
+  }
+}
+
+int gpr_split_host_port(const char* name, char** host, char** port) {
+  const char* host_start;
+  size_t host_len;
+  const char* port_start;
+
+  *host = nullptr;
+  *port = nullptr;
+
+  if (name[0] == '[') {
+    /* Parse a bracketed host, typically an IPv6 literal. */
+    const char* rbracket = strchr(name, ']');
+    if (rbracket == nullptr) {
+      /* Unmatched [ */
+      return 0;
+    }
+    if (rbracket[1] == '\0') {
+      /* ]<end> */
+      port_start = nullptr;
+    } else if (rbracket[1] == ':') {
+      /* ]:<port?> */
+      port_start = rbracket + 2;
+    } else {
+      /* ]<invalid> */
+      return 0;
+    }
+    host_start = name + 1;
+    host_len = (size_t)(rbracket - host_start);
+    if (memchr(host_start, ':', host_len) == nullptr) {
+      /* Require all bracketed hosts to contain a colon, because a hostname or
+         IPv4 address should never use brackets. */
+      return 0;
+    }
+  } else {
+    const char* colon = strchr(name, ':');
+    if (colon != nullptr && strchr(colon + 1, ':') == nullptr) {
+      /* Exactly 1 colon.  Split into host:port. */
+      host_start = name;
+      host_len = (size_t)(colon - name);
+      port_start = colon + 1;
+    } else {
+      /* 0 or 2+ colons.  Bare hostname or IPv6 litearal. */
+      host_start = name;
+      host_len = strlen(name);
+      port_start = nullptr;
+    }
+  }
+
+  /* Allocate return values. */
+  *host = (char*)gpr_malloc(host_len + 1);
+  memcpy(*host, host_start, host_len);
+  (*host)[host_len] = '\0';
+
+  if (port_start != nullptr) {
+    *port = gpr_strdup(port_start);
+  }
+
+  return 1;
+}