diff options
author | vvvv <vvvv@yandex-team.com> | 2024-11-07 12:29:36 +0300 |
---|---|---|
committer | vvvv <vvvv@yandex-team.com> | 2024-11-07 13:49:47 +0300 |
commit | d4c258e9431675bab6745c8638df6e3dfd4dca6b (patch) | |
tree | b5efcfa11351152a4c872fccaea35749141c0b11 /yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h | |
parent | 13a4f274caef5cfdaf0263b24e4d6bdd5521472b (diff) | |
download | ydb-d4c258e9431675bab6745c8638df6e3dfd4dca6b.tar.gz |
Moved other yql/essentials libs YQL-19206
init
commit_hash:7d4c435602078407bbf20dd3c32f9c90d2bbcbc0
Diffstat (limited to 'yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h')
-rw-r--r-- | yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h b/yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h new file mode 100644 index 00000000000..fd267d54804 --- /dev/null +++ b/yql/essentials/parser/pg_wrapper/postgresql/src/include/utils/arrayaccess.h @@ -0,0 +1,118 @@ +/*------------------------------------------------------------------------- + * + * arrayaccess.h + * Declarations for element-by-element access to Postgres arrays. + * + * + * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/utils/arrayaccess.h + * + *------------------------------------------------------------------------- + */ +#ifndef ARRAYACCESS_H +#define ARRAYACCESS_H + +#include "access/tupmacs.h" +#include "utils/array.h" + + +/* + * Functions for iterating through elements of a flat or expanded array. + * These require a state struct "array_iter iter". + * + * Use "array_iter_setup(&iter, arrayptr);" to prepare to iterate, and + * "datumvar = array_iter_next(&iter, &isnullvar, index, ...);" to fetch + * the next element into datumvar/isnullvar. + * "index" must be the zero-origin element number; we make caller provide + * this since caller is generally counting the elements anyway. Despite + * that, these functions can only fetch elements sequentially. + */ + +typedef struct array_iter +{ + /* datumptr being NULL or not tells if we have flat or expanded array */ + + /* Fields used when we have an expanded array */ + Datum *datumptr; /* Pointer to Datum array */ + bool *isnullptr; /* Pointer to isnull array */ + + /* Fields used when we have a flat array */ + char *dataptr; /* Current spot in the data area */ + bits8 *bitmapptr; /* Current byte of the nulls bitmap, or NULL */ + int bitmask; /* mask for current bit in nulls bitmap */ +} array_iter; + + +static inline void +array_iter_setup(array_iter *it, AnyArrayType *a) +{ + if (VARATT_IS_EXPANDED_HEADER(a)) + { + if (a->xpn.dvalues) + { + it->datumptr = a->xpn.dvalues; + it->isnullptr = a->xpn.dnulls; + /* we must fill all fields to prevent compiler warnings */ + it->dataptr = NULL; + it->bitmapptr = NULL; + } + else + { + /* Work with flat array embedded in the expanded datum */ + it->datumptr = NULL; + it->isnullptr = NULL; + it->dataptr = ARR_DATA_PTR(a->xpn.fvalue); + it->bitmapptr = ARR_NULLBITMAP(a->xpn.fvalue); + } + } + else + { + it->datumptr = NULL; + it->isnullptr = NULL; + it->dataptr = ARR_DATA_PTR((ArrayType *) a); + it->bitmapptr = ARR_NULLBITMAP((ArrayType *) a); + } + it->bitmask = 1; +} + +static inline Datum +array_iter_next(array_iter *it, bool *isnull, int i, + int elmlen, bool elmbyval, char elmalign) +{ + Datum ret; + + if (it->datumptr) + { + ret = it->datumptr[i]; + *isnull = it->isnullptr ? it->isnullptr[i] : false; + } + else + { + if (it->bitmapptr && (*(it->bitmapptr) & it->bitmask) == 0) + { + *isnull = true; + ret = (Datum) 0; + } + else + { + *isnull = false; + ret = fetch_att(it->dataptr, elmbyval, elmlen); + it->dataptr = att_addlength_pointer(it->dataptr, elmlen, + it->dataptr); + it->dataptr = (char *) att_align_nominal(it->dataptr, elmalign); + } + it->bitmask <<= 1; + if (it->bitmask == 0x100) + { + if (it->bitmapptr) + it->bitmapptr++; + it->bitmask = 1; + } + } + + return ret; +} + +#endif /* ARRAYACCESS_H */ |