Implement RFC 2: Initial integration of "GDAL SRS barn" work

This work mostly consists of:
- a C++ implementation of the ISO-19111:2018 / OGC Topic 2
  "Referencing by coordinates" classes to represent Datums,
  Coordinate systems, CRSs (Coordinate Reference Systems) and
  Coordinate Operations.
- methods to convert between this C++ modeling and WKT1, WKT2
  and PROJ string representations of those objects
- management and query of a SQLite3 database of CRS and Coordinate Operation definition
- a C API binding part of those capabilities

This is all-in-one squashed commit of the work of
https://github.com/OSGeo/proj.4/pull/1040

1 files changed, 28 insertions, 0 deletions

diff --git a/data/sql/commit.sql b/data/sql/commit.sql
new file mode 100644
index 00000000..346c5b76
--- /dev/null
+++ b/data/sql/commit.sql
@@ -0,0 +1,28 @@
+COMMIT;
+
+-- Do an explicit foreign_key_check as foreign key checking is a no-op within
+-- a transaction. Unfortunately we can't ask for this to be an error, so this
+-- is just for verbose output. In Makefile, we check this separately
+PRAGMA foreign_key_check;
+
+-- Final consistency checks
+CREATE TABLE dummy(foo);
+CREATE TRIGGER final_checks
+BEFORE INSERT ON dummy
+FOR EACH ROW BEGIN
+
+    -- check that view definitions have no error
+    SELECT RAISE(ABORT, 'corrupt definition of coordinate_operation_view')
+        WHERE (SELECT 1 FROM coordinate_operation_view LIMIT 1) = 0;
+    SELECT RAISE(ABORT, 'corrupt definition of crs_view')
+        WHERE (SELECT 1 FROM crs_view LIMIT 1) = 0;
+    SELECT RAISE(ABORT, 'corrupt definition of object_view')
+        WHERE (SELECT 1 FROM object_view LIMIT 1) = 0;
+    SELECT RAISE(ABORT, 'corrupt definition of authority_list')
+        WHERE (SELECT 1 FROM authority_list LIMIT 1) = 0;
+END;
+INSERT INTO dummy DEFAULT VALUES;
+DROP TRIGGER final_checks;
+DROP TABLE dummy;
+
+VACUUM;
\ No newline at end of file