diff options
| author | vvvv <[email protected]> | 2024-11-07 12:29:36 +0300 | 
|---|---|---|
| committer | vvvv <[email protected]> | 2024-11-07 13:49:47 +0300 | 
| commit | d4c258e9431675bab6745c8638df6e3dfd4dca6b (patch) | |
| tree | b5efcfa11351152a4c872fccaea35749141c0b11 /yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h | |
| parent | 13a4f274caef5cfdaf0263b24e4d6bdd5521472b (diff) | |
Moved other yql/essentials libs YQL-19206
init
commit_hash:7d4c435602078407bbf20dd3c32f9c90d2bbcbc0
Diffstat (limited to 'yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h')
| -rw-r--r-- | yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h | 67 | 
1 files changed, 67 insertions, 0 deletions
diff --git a/yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h b/yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h new file mode 100644 index 00000000000..322aeb3ff9d --- /dev/null +++ b/yql/essentials/parser/pg_wrapper/postgresql/src/include/access/sdir.h @@ -0,0 +1,67 @@ +/*------------------------------------------------------------------------- + * + * sdir.h + *	  POSTGRES scan direction definitions. + * + * + * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/access/sdir.h + * + *------------------------------------------------------------------------- + */ +#ifndef SDIR_H +#define SDIR_H + + +/* + * Defines the direction for scanning a table or an index.  Scans are never + * invoked using NoMovementScanDirectionScans.  For convenience, we use the + * values -1 and 1 for backward and forward scans.  This allows us to perform + * a few mathematical tricks such as what is done in ScanDirectionCombine. + */ +typedef enum ScanDirection +{ +	BackwardScanDirection = -1, +	NoMovementScanDirection = 0, +	ForwardScanDirection = 1 +} ScanDirection; + +/* + * Determine the net effect of two direction specifications. + * This relies on having ForwardScanDirection = +1, BackwardScanDirection = -1, + * and will probably not do what you want if applied to any other values. + */ +#define ScanDirectionCombine(a, b)  ((a) * (b)) + +/* + * ScanDirectionIsValid + *		True iff scan direction is valid. + */ +#define ScanDirectionIsValid(direction) \ +	((bool) (BackwardScanDirection <= (direction) && \ +			 (direction) <= ForwardScanDirection)) + +/* + * ScanDirectionIsBackward + *		True iff scan direction is backward. + */ +#define ScanDirectionIsBackward(direction) \ +	((bool) ((direction) == BackwardScanDirection)) + +/* + * ScanDirectionIsNoMovement + *		True iff scan direction indicates no movement. + */ +#define ScanDirectionIsNoMovement(direction) \ +	((bool) ((direction) == NoMovementScanDirection)) + +/* + * ScanDirectionIsForward + *		True iff scan direction is forward. + */ +#define ScanDirectionIsForward(direction) \ +	((bool) ((direction) == ForwardScanDirection)) + +#endif							/* SDIR_H */  | 
