VM: Make more globals constant where easily possible.

runtime/vm/service.cc

Index: runtime/vm/service.cc
diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index 50d1aa401c08cd99a4448253b331247189b2f6ac..454726c3fd936badb65c86e70f411c6fd457ef75 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -97,7 +97,7 @@ char* RingServiceIdZone::GetServiceId(const Object& obj) {
 EmbedderServiceHandler* Service::isolate_service_handler_head_ = NULL;
 EmbedderServiceHandler* Service::root_service_handler_head_ = NULL;
 struct ServiceMethodDescriptor;
-ServiceMethodDescriptor* FindMethod(const char* method_name);
+const ServiceMethodDescriptor* FindMethod(const char* method_name);
 
 
 // Support for streams defined in embedders.
@@ -491,7 +491,7 @@ class IdParameter : public MethodParameter {
 
 class EnumParameter : public MethodParameter {
  public:
-  EnumParameter(const char* name, bool required, const char** enums)
+  EnumParameter(const char* name, bool required, const char* const* enums)
       : MethodParameter(name, required),
         enums_(enums) {
   }
@@ -509,14 +509,14 @@ class EnumParameter : public MethodParameter {
   }
 
  private:
-  const char** enums_;
+  const char* const* enums_;
 };
 
 
 // If the key is not found, this function returns the last element in the
 // values array. This can be used to encode the default value.
 template<typename T>
-T EnumMapper(const char* value, const char** enums, T* values) {
+T EnumMapper(const char* value, const char* const* enums, T* values) {
   ASSERT(value != NULL);
   intptr_t i = 0;
   for (i = 0; enums[i] != NULL; i++) {
@@ -644,7 +644,7 @@ void Service::InvokeMethod(Isolate* I, const Array& msg) {
     }
     const char* c_method_name = method_name.ToCString();
 
-    ServiceMethodDescriptor* method = FindMethod(c_method_name);
+    const ServiceMethodDescriptor* method = FindMethod(c_method_name);
     if (method != NULL) {
       if (!ValidateParameters(method->parameters, &js)) {
         js.PostReply();
@@ -1385,12 +1385,12 @@ static RawObject* LookupHeapObjectCode(Isolate* isolate,
     return Object::sentinel().raw();
   }
   uword pc;
-  static const char* kCollectedPrefix = "collected-";
+  static const char* const kCollectedPrefix = "collected-";
   static intptr_t kCollectedPrefixLen = strlen(kCollectedPrefix);
-  static const char* kNativePrefix = "native-";
-  static intptr_t kNativePrefixLen = strlen(kNativePrefix);
-  static const char* kReusedPrefix = "reused-";
-  static intptr_t kReusedPrefixLen = strlen(kReusedPrefix);
+  static const char* const kNativePrefix = "native-";
+  static const intptr_t kNativePrefixLen = strlen(kNativePrefix);
+  static const char* const kReusedPrefix = "reused-";
+  static const intptr_t kReusedPrefixLen = strlen(kReusedPrefix);
   const char* id = parts[1];
   if (strncmp(kCollectedPrefix, id, kCollectedPrefixLen) == 0) {
     if (!GetUnsignedIntegerId(&id[kCollectedPrefixLen], &pc, 16)) {
@@ -2446,14 +2446,14 @@ static bool GetIsolateMetric(Thread* thread, JSONStream* js) {
     return true;
   }
   // Verify id begins with "metrics/".
-  static const char* kMetricIdPrefix = "metrics/";
+  static const char* const kMetricIdPrefix = "metrics/";
   static intptr_t kMetricIdPrefixLen = strlen(kMetricIdPrefix);
   if (strncmp(metric_id, kMetricIdPrefix, kMetricIdPrefixLen) != 0) {
     PrintInvalidParamError(js, "metricId");
     return true;
   }
   // Check if id begins with "metrics/native/".
-  static const char* kNativeMetricIdPrefix = "metrics/native/";
+  static const char* const kNativeMetricIdPrefix = "metrics/native/";
   static intptr_t kNativeMetricIdPrefixLen = strlen(kNativeMetricIdPrefix);
   const bool native_metric =
       strncmp(metric_id, kNativeMetricIdPrefix, kNativeMetricIdPrefixLen) == 0;
@@ -2662,7 +2662,7 @@ static bool GetTagProfile(Thread* thread, JSONStream* js) {
 }
 
 
-static const char* tags_enum_names[] = {
+static const char* const tags_enum_names[] = {
   "None",
   "UserVM",
   "UserOnly",
@@ -2672,7 +2672,7 @@ static const char* tags_enum_names[] = {
 };
 
 
-static Profile::TagOrder tags_enum_values[] = {
+static const Profile::TagOrder tags_enum_values[] = {
   Profile::kNoTags,
   Profile::kUserVM,
   Profile::kUser,
@@ -3397,7 +3397,7 @@ static bool SetTraceClassAllocation(Thread* thread, JSONStream* js) {
 }
 
 
-static ServiceMethodDescriptor service_methods_[] = {
+static const ServiceMethodDescriptor service_methods_[] = {
   { "_dumpIdZone", DumpIdZone, NULL },
   { "_echo", Echo,
     NULL },
@@ -3504,11 +3504,11 @@ static ServiceMethodDescriptor service_methods_[] = {
 };
 
 
-ServiceMethodDescriptor* FindMethod(const char* method_name) {
+const ServiceMethodDescriptor* FindMethod(const char* method_name) {
   intptr_t num_methods = sizeof(service_methods_) /
                          sizeof(service_methods_[0]);
   for (intptr_t i = 0; i < num_methods; i++) {
-    ServiceMethodDescriptor& method = service_methods_[i];
+    const ServiceMethodDescriptor& method = service_methods_[i];
     if (strcmp(method_name, method.name) == 0) {
       return &method;
     }