Move LockClauseStrength, LockWaitPolicy into new file nodes/lockoptions.h.

Commit df630b0dd5ea2de52972d456f5978a012436115e moved enum LockWaitPolicy
into its very own header file utils/lockwaitpolicy.h, which does not seem
like a great idea from here.  First, it's still a node-related declaration,
and second, a file named like that can never sensibly be used for anything
else.  I do not think we want to encourage a one-typedef-per-header-file
approach.  The upcoming foreign table inheritance patch was doubling down
on this bad idea by moving enum LockClauseStrength into its *own*
can-never-be-used-for-anything-else file.  Instead, let's put them both in
a file named nodes/lockoptions.h.  (They do seem to need a separate header
file because we need them in both parsenodes.h and plannodes.h, and we
don't want either of those including the other.  Past practice might
suggest adding them to nodes/nodes.h, but they don't seem sufficiently
globally useful to justify that.)

Committed separately since there's no functional change here, just some
header-file refactoring.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/include/nodes/lockoptions.h b/src/include/nodes/lockoptions.h
new file mode 100644
index 00000000000..55324baf40f
--- /dev/null
+++ b/src/include/nodes/lockoptions.h
@@ -0,0 +1,45 @@
+/*-------------------------------------------------------------------------
+ *
+ * lockoptions.h
+ *	  Common header for some locking-related declarations.
+ *
+ *
+ * Copyright (c) 2014-2015, PostgreSQL Global Development Group
+ *
+ * src/include/nodes/lockoptions.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef LOCKOPTIONS_H
+#define LOCKOPTIONS_H
+
+/*
+ * This enum represents the different strengths of FOR UPDATE/SHARE clauses.
+ * The ordering here is important, because the highest numerical value takes
+ * precedence when a RTE is specified multiple ways.  See applyLockingClause.
+ */
+typedef enum LockClauseStrength
+{
+	LCS_FORKEYSHARE,			/* FOR KEY SHARE */
+	LCS_FORSHARE,				/* FOR SHARE */
+	LCS_FORNOKEYUPDATE,			/* FOR NO KEY UPDATE */
+	LCS_FORUPDATE				/* FOR UPDATE */
+} LockClauseStrength;
+
+/*
+ * This enum controls how to deal with rows being locked by FOR UPDATE/SHARE
+ * clauses (i.e., it represents the NOWAIT and SKIP LOCKED options).
+ * The ordering here is important, because the highest numerical value takes
+ * precedence when a RTE is specified multiple ways.  See applyLockingClause.
+ */
+typedef enum LockWaitPolicy
+{
+	/* Wait for the lock to become available (default behavior) */
+	LockWaitBlock,
+	/* Skip rows that can't be locked (SKIP LOCKED) */
+	LockWaitSkip,
+	/* Raise an error if a row cannot be locked (NOWAIT) */
+	LockWaitError
+} LockWaitPolicy;
+
+#endif   /* LOCKOPTIONS_H */