Revise collation derivation method and expression-tree representation.

[postgresql] / src / include / fmgr.h

diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 7539acace82db46549bd93e6c49dfdf9c2cff18a..9e5224d374da46f6535dd68282f91f6ec8deea7f 100644 (file)
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -40,6 +40,11 @@ typedef Datum (*PGFunction) (FunctionCallInfo fcinfo);
  * before a function can be called through fmgr.  If the same function is
  * to be called multiple times, the lookup need be done only once and the
  * info struct saved for re-use.
+ *
+ * Note that fn_collation and fn_expr really are parse-time-determined
+ * information about the arguments, rather than about the function itself.
+ * But it's convenient to store them here rather than in FunctionCallInfoData,
+ * where they might more logically belong.
  */
 typedef struct FmgrInfo
 {
@@ -50,7 +55,7 @@ typedef struct FmgrInfo
        bool            fn_strict;              /* function is "strict" (NULL in => NULL out) */
        bool            fn_retset;              /* function returns a set */
        unsigned char fn_stats;         /* collect stats if track_functions > this */
-       Oid                     fn_collation;   /* collation to use */
+       Oid                     fn_collation;   /* collation that function should use */
        void       *fn_extra;           /* extra space for use by handler */
        MemoryContext fn_mcxt;          /* memory context to store fn_extra in */
        fmNodePtr       fn_expr;                /* expression parse tree for call, or NULL */
@@ -84,15 +89,11 @@ extern void fmgr_info(Oid functionId, FmgrInfo *finfo);
 extern void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo,
                          MemoryContext mcxt);
 
-/*
- * Initialize the fn_collation field
- */
-extern void fmgr_info_collation(Oid collationId, FmgrInfo *finfo);
-
-/*
- * Initialize the fn_expr field and set the collation based on it
- */
-extern void fmgr_info_expr(fmNodePtr expr, FmgrInfo *finfo);
+/* Macros for setting the fn_collation and fn_expr fields */
+#define fmgr_info_set_collation(collationId, finfo) \
+       ((finfo)->fn_collation = (collationId))
+#define fmgr_info_set_expr(expr, finfo) \
+       ((finfo)->fn_expr = (expr))
 
 /*
  * Copy an FmgrInfo struct
@@ -146,6 +147,12 @@ extern void fmgr_info_copy(FmgrInfo *dstinfo, FmgrInfo *srcinfo,
 /* Standard parameter list for fmgr-compatible functions */
 #define PG_FUNCTION_ARGS       FunctionCallInfo fcinfo
 
+/*
+ * Get collation function should use.
+ */
+#define PG_GET_COLLATION() \
+       (fcinfo->flinfo ? fcinfo->flinfo->fn_collation : InvalidOid)
+
 /*
  * Get number of arguments passed to function.
  */
@@ -307,7 +314,6 @@ extern struct varlena *pg_detoast_datum_packed(struct varlena * datum);
 #define PG_RETURN_VARCHAR_P(x) PG_RETURN_POINTER(x)
 #define PG_RETURN_HEAPTUPLEHEADER(x)  PG_RETURN_POINTER(x)
 
-#define PG_GET_COLLATION()             (fcinfo->flinfo ? fcinfo->flinfo->fn_collation : InvalidOid)
 
 /*-------------------------------------------------------------------------
  *             Support for detecting call convention of dynamically-loaded functions
@@ -450,7 +456,7 @@ extern Datum DirectFunctionCall9(PGFunction func, Datum arg1, Datum arg2,
                                        Datum arg6, Datum arg7, Datum arg8,
                                        Datum arg9);
 
-/* the same but passing a collation */
+/* The same, but passing a collation to use */
 extern Datum DirectFunctionCall1WithCollation(PGFunction func, Oid collation,
                                                                                          Datum arg1);
 extern Datum DirectFunctionCall2WithCollation(PGFunction func, Oid collation,