Add UTC time representation and conversions (#63)

Author: jbangelo

Cargo.toml

@@ -8,10 +8,14 @@ readme = "README.md"
 repository = "https://github.com/swift-nav/swiftnav-rs"
 license = "LGPL-3.0"
 
+[dependencies]
+chrono = { version = "0.4", optional = true }
+
 [build-dependencies]
 bindgen = "0.59"
 cmake = "0.1"
 
 [features]
 default = ["testcpp"]
 testcpp = []
+chrono-support = ["chrono"]

build.rs

@@ -61,9 +61,21 @@ fn main() {
         .blocklist_type("u16")
         .blocklist_type("u32")
         .allowlist_type("gps_time_t")
+        .allowlist_type("utc_params_t")
+        .allowlist_type("utc_tm")
         .allowlist_function("gpsdifftime")
         .allowlist_function("gps_time_valid")
         .allowlist_function("add_secs")
+        .allowlist_function("decode_utc_parameters")
+        .allowlist_function("gps2utc")
+        .allowlist_function("date2mjd")
+        .allowlist_function("mjd2utc")
+        .allowlist_function("utc2mjd")
+        .allowlist_function("date2utc")
+        .allowlist_function("get_gps_utc_offset")
+        .allowlist_function("is_leap_second_event")
+        .allowlist_function("round_to_epoch")
+        .allowlist_function("floor_to_epoch")
         .allowlist_var("FLOAT_EQUALITY_EPS")
         .allowlist_var("MINUTE_SECS")
         .allowlist_var("HOUR_SECS")