[core] move from microsecond precision timestamp to integer second precision

4 files changed, 24 insertions, 13 deletions

diff --git a/include/mbgl/storage/resource.hpp b/include/mbgl/storage/resource.hpp
index 296dff7f3d..01c2ee4e39 100644
--- a/include/mbgl/storage/resource.hpp
+++ b/include/mbgl/storage/resource.hpp
@@ -29,8 +29,14 @@ public:
         int8_t z;
     };
 
-    Resource(Kind kind_, const std::string& url_, optional<TileData> tileData_ = {})
+    enum Necessity : bool {
+        Optional = false,
+        Required = true,
+    };
+
+    Resource(Kind kind_, const std::string& url_, optional<TileData> tileData_ = {}, Necessity necessity_ = Required)
         : kind(kind_),
+          necessity(necessity_),
           url(url_),
           tileData(std::move(tileData_)) {
     }
@@ -41,7 +47,8 @@ public:
                          float pixelRatio,
                          int32_t x,
                          int32_t y,
-                         int8_t z);
+                         int8_t z,
+                         Necessity = Required);
     static Resource glyphs(const std::string& urlTemplate,
                            const FontStack& fontStack,
                            const std::pair<uint16_t, uint16_t>& glyphRange);
@@ -49,13 +56,14 @@ public:
     static Resource spriteJSON(const std::string& base, float pixelRatio);
 
     Kind kind;
+    Necessity necessity;
     std::string url;
 
     // Includes auxiliary data if this is a tile request.
     optional<TileData> tileData;
 
-    optional<SystemTimePoint> priorModified = {};
-    optional<SystemTimePoint> priorExpires = {};
+    optional<Timestamp> priorModified = {};
+    optional<Timestamp> priorExpires = {};
     optional<std::string> priorEtag = {};
 };
 
diff --git a/include/mbgl/storage/response.hpp b/include/mbgl/storage/response.hpp
index bec1efe6b1..f140e42b02 100644
--- a/include/mbgl/storage/response.hpp
+++ b/include/mbgl/storage/response.hpp
@@ -30,8 +30,8 @@ public:
     // The actual data of the response. Present only for non-error, non-notModified responses.
     std::shared_ptr<const std::string> data;
 
-    optional<SystemTimePoint> modified;
-    optional<SystemTimePoint> expires;
+    optional<Timestamp> modified;
+    optional<Timestamp> expires;
     optional<std::string> etag;
 };
 
diff --git a/include/mbgl/util/chrono.hpp b/include/mbgl/util/chrono.hpp
index 8e0da1419a..81f05d610d 100644
--- a/include/mbgl/util/chrono.hpp
+++ b/include/mbgl/util/chrono.hpp
@@ -7,7 +7,6 @@
 namespace mbgl {
 
 using Clock = std::chrono::steady_clock;
-using SystemClock = std::chrono::system_clock;
 
 using Seconds = std::chrono::seconds;
 using Milliseconds = std::chrono::milliseconds;
@@ -15,18 +14,22 @@ using Milliseconds = std::chrono::milliseconds;
 using TimePoint = Clock::time_point;
 using Duration  = Clock::duration;
 
-using SystemTimePoint = SystemClock::time_point;
-using SystemDuration = SystemClock::duration;
+// Used to measure second-precision times, such as times gathered from HTTP responses.
+using Timestamp = std::chrono::time_point<std::chrono::system_clock, Seconds>;
 
 namespace util {
 
+inline Timestamp now() {
+    return std::chrono::time_point_cast<Seconds>(std::chrono::system_clock::now());
+}
+
 // Returns the RFC1123 formatted date. E.g. "Tue, 04 Nov 2014 02:13:24 GMT"
-std::string rfc1123(SystemTimePoint);
+std::string rfc1123(Timestamp);
 
 // YYYY-mm-dd HH:MM:SS e.g. "2015-11-26 16:11:23"
-std::string iso8601(SystemTimePoint);
+std::string iso8601(Timestamp);
 
-SystemTimePoint parseTimePoint(const char *);
+Timestamp parseTimestamp(const char *);
 
 // C++17 polyfill
 template <class Rep, class Period, class = std::enable_if_t<
diff --git a/include/mbgl/util/constants.hpp b/include/mbgl/util/constants.hpp
index 58f4143766..3517299df2 100644
--- a/include/mbgl/util/constants.hpp
+++ b/include/mbgl/util/constants.hpp
@@ -39,7 +39,7 @@ constexpr double MAX_ZOOM = 25.5;
 constexpr uint64_t DEFAULT_MAX_CACHE_SIZE = 50 * 1024 * 1024;;
 
 constexpr Duration DEFAULT_FADE_DURATION = Milliseconds(300);
-constexpr SystemDuration CLOCK_SKEW_RETRY_TIMEOUT = Seconds(30);
+constexpr Seconds CLOCK_SKEW_RETRY_TIMEOUT { 30 };
 
 } // namespace util