[core] unify URL prefix detection (asset:// and mapbox://)

platform/default/online_file_source.cpp

@@ -14,21 +14,13 @@
 #include <mbgl/util/async_task.hpp>
 #include <mbgl/util/noncopyable.hpp>
 #include <mbgl/util/timer.hpp>
-
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wshadow"
-#pragma GCC diagnostic ignored "-Wunknown-pragmas"
-#pragma GCC diagnostic ignored "-Wunused-local-typedefs"
-#include <boost/algorithm/string.hpp>
-#pragma GCC diagnostic pop
+#include <mbgl/util/url.hpp>
 
 #include <algorithm>
 #include <cassert>
 #include <set>
 #include <unordered_map>
 
-namespace algo = boost::algorithm;
-
 namespace mbgl {
 
 class RequestBase;
@@ -299,7 +291,7 @@ void OnlineFileSource::Impl::startRealRequest(OnlineFileRequestImpl& request) {
         reschedule(request);
     };
 
-    if (algo::starts_with(request.resource.url, "asset://")) {
+    if (util::isAssetURL(request.resource.url)) {
         request.realRequest =
             assetContext->createRequest(request.resource.url, callback, assetRoot);
     } else {

src/mbgl/map/map_context.cpp

@@ -21,6 +21,7 @@
 #include <mbgl/util/texture_pool.hpp>
 #include <mbgl/util/exception.hpp>
 #include <mbgl/util/string.hpp>
+#include <mbgl/util/mapbox.hpp>
 
 #include <algorithm>
 
@@ -114,7 +115,8 @@ void MapContext::setStyleURL(const std::string& url) {
         styleRequest = nullptr;
 
         if (res.error) {
-            if (res.error->reason == Response::Error::Reason::NotFound && styleURL.find("mapbox://") == 0) {
+            if (res.error->reason == Response::Error::Reason::NotFound &&
+                util::mapbox::isMapboxURL(styleURL)) {
                 Log::Error(Event::Setup, "style %s could not be found or is an incompatible legacy map or style", styleURL.c_str());
             } else {
                 Log::Error(Event::Setup, "loading style failed: %s", res.error->message.c_str());

src/mbgl/util/mapbox.cpp

@@ -13,7 +13,7 @@ const std::string protocol = "mapbox://";
 const std::string baseURL = "https://api.mapbox.com/";
 
 bool isMapboxURL(const std::string& url) {
-    return url.compare(0, protocol.length(), protocol) == 0;
+    return std::equal(protocol.begin(), protocol.end(), url.begin());
 }
 
 std::vector<std::string> getMapboxURLPathname(const std::string& url) {

src/mbgl/util/mapbox.hpp

@@ -8,6 +8,8 @@ namespace mbgl {
 namespace util {
 namespace mapbox {
 
+bool isMapboxURL(const std::string& url);
+
 std::string normalizeSourceURL(const std::string& url, const std::string& accessToken);
 std::string normalizeStyleURL(const std::string& url, const std::string& accessToken);
 std::string normalizeSpriteURL(const std::string& url, const std::string& accessToken);

src/mbgl/util/url.cpp

@@ -47,5 +47,13 @@ std::string percentDecode(const std::string& input) {
     return decoded;
 }
 
+namespace {
+const std::string assetProtocol = "asset://";
+}
+
+bool isAssetURL(const std::string& url) {
+    return std::equal(assetProtocol.begin(), assetProtocol.end(), url.begin());
+}
+
 } // namespace util
 } // namespace mbgl

src/mbgl/util/url.hpp

@@ -9,6 +9,8 @@ namespace util {
 std::string percentEncode(const std::string&);
 std::string percentDecode(const std::string&);
 
+bool isAssetURL(const std::string&);
+
 } // namespace util
 } // namespace mbgl