Move Timestamp/Interval typedefs and basic macros into datatype/timestamp.h.

As per my recent proposal, this refactors things so that these typedefs and
macros are available in a header that can be included in frontend-ish code.
I also changed various headers that were undesirably including
utils/timestamp.h to include datatype/timestamp.h instead.  Unsurprisingly,
this showed that half the system was getting utils/timestamp.h by way of
xlog.h.

No actual code changes here, just header refactoring.

7 files changed, 11 insertions, 4 deletions

diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index e737e720f5b..b06faf0c720 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -27,6 +27,7 @@
 #include "utils/array.h"
 #include "utils/builtins.h"
 #include "utils/date.h"
+#include "utils/datetime.h"
 #include "utils/nabstime.h"
 
 /*
diff --git a/src/backend/utils/adt/genfile.c b/src/backend/utils/adt/genfile.c
index dfe38f555f5..6b3f77fec14 100644
--- a/src/backend/utils/adt/genfile.c
+++ b/src/backend/utils/adt/genfile.c
@@ -28,6 +28,7 @@
 #include "storage/fd.h"
 #include "utils/builtins.h"
 #include "utils/memutils.h"
+#include "utils/timestamp.h"
 
 typedef struct
 {
diff --git a/src/backend/utils/adt/misc.c b/src/backend/utils/adt/misc.c
index 5a77340bdb0..63ec6fd9d4e 100644
--- a/src/backend/utils/adt/misc.c
+++ b/src/backend/utils/adt/misc.c
@@ -20,8 +20,8 @@
 #include <math.h>
 
 #include "catalog/catalog.h"
-#include "catalog/pg_type.h"
 #include "catalog/pg_tablespace.h"
+#include "catalog/pg_type.h"
 #include "commands/dbcommands.h"
 #include "funcapi.h"
 #include "miscadmin.h"
@@ -30,8 +30,9 @@
 #include "storage/fd.h"
 #include "storage/pmsignal.h"
 #include "storage/procarray.h"
-#include "utils/builtins.h"
 #include "tcop/tcopprot.h"
+#include "utils/builtins.h"
+#include "utils/timestamp.h"
 
 #define atooid(x)  ((Oid) strtoul((x), NULL, 10))
 
diff --git a/src/backend/utils/adt/nabstime.c b/src/backend/utils/adt/nabstime.c
index 6771e78af8e..02dc24d5135 100644
--- a/src/backend/utils/adt/nabstime.c
+++ b/src/backend/utils/adt/nabstime.c
@@ -25,6 +25,7 @@
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
 #include "utils/builtins.h"
+#include "utils/datetime.h"
 #include "utils/nabstime.h"
 
 #define MIN_DAYNUM (-24856)		/* December 13, 1901 */
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index d065542e047..7792b33da0d 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -14,13 +14,14 @@
  */
 #include "postgres.h"
 
+#include "catalog/pg_type.h"
 #include "funcapi.h"
+#include "libpq/ip.h"
 #include "miscadmin.h"
 #include "pgstat.h"
-#include "catalog/pg_type.h"
 #include "utils/builtins.h"
 #include "utils/inet.h"
-#include "libpq/ip.h"
+#include "utils/timestamp.h"
 
 /* bogus ... these externs should be in a header file */
 extern Datum pg_stat_get_numscans(PG_FUNCTION_ARGS);
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index 5d999e6bfa2..3e846799563 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -124,6 +124,7 @@
 #include "utils/selfuncs.h"
 #include "utils/spccache.h"
 #include "utils/syscache.h"
+#include "utils/timestamp.h"
 #include "utils/tqual.h"
 
 
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index 186548dcba5..609758ecd23 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -24,6 +24,7 @@
 #include "miscadmin.h"
 #include "utils/builtins.h"
 #include "utils/memutils.h"
+#include "utils/timestamp.h"
 
 /*
  * Estimate of the maximum number of open portals a user would have,