#include "postgres.h"
#include "access/htup_details.h"
#include "catalog/catalog.h"
#include "catalog/namespace.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
#include "utils/builtins.h"
#include "utils/rel.h"
Go to the source code of this file.
Functions | |
Datum | get_raw_page (PG_FUNCTION_ARGS) |
Datum | get_raw_page_fork (PG_FUNCTION_ARGS) |
Datum | page_header (PG_FUNCTION_ARGS) |
static bytea * | get_raw_page_internal (text *relname, ForkNumber forknum, BlockNumber blkno) |
PG_FUNCTION_INFO_V1 (get_raw_page) | |
PG_FUNCTION_INFO_V1 (get_raw_page_fork) | |
PG_FUNCTION_INFO_V1 (page_header) | |
Variables | |
PG_MODULE_MAGIC |
Datum get_raw_page | ( | PG_FUNCTION_ARGS | ) |
Definition at line 45 of file rawpage.c.
References ereport, errhint(), errmsg(), ERROR, get_raw_page_internal(), MAIN_FORKNUM, PG_GETARG_TEXT_P, PG_GETARG_UINT32, PG_NARGS, and PG_RETURN_BYTEA_P.
{ text *relname = PG_GETARG_TEXT_P(0); uint32 blkno = PG_GETARG_UINT32(1); bytea *raw_page; /* * We don't normally bother to check the number of arguments to a C * function, but here it's needed for safety because early 8.4 beta * releases mistakenly redefined get_raw_page() as taking three arguments. */ if (PG_NARGS() != 2) ereport(ERROR, (errmsg("wrong number of arguments to get_raw_page()"), errhint("Run the updated pageinspect.sql script."))); raw_page = get_raw_page_internal(relname, MAIN_FORKNUM, blkno); PG_RETURN_BYTEA_P(raw_page); }
Datum get_raw_page_fork | ( | PG_FUNCTION_ARGS | ) |
Definition at line 74 of file rawpage.c.
References forkname_to_number(), get_raw_page_internal(), PG_GETARG_TEXT_P, PG_GETARG_UINT32, PG_RETURN_BYTEA_P, and text_to_cstring().
{ text *relname = PG_GETARG_TEXT_P(0); text *forkname = PG_GETARG_TEXT_P(1); uint32 blkno = PG_GETARG_UINT32(2); bytea *raw_page; ForkNumber forknum; forknum = forkname_to_number(text_to_cstring(forkname)); raw_page = get_raw_page_internal(relname, forknum, blkno); PG_RETURN_BYTEA_P(raw_page); }
static bytea * get_raw_page_internal | ( | text * | relname, | |
ForkNumber | forknum, | |||
BlockNumber | blkno | |||
) | [static] |
Definition at line 93 of file rawpage.c.
References AccessShareLock, buf, BUFFER_LOCK_SHARE, BUFFER_LOCK_UNLOCK, BufferGetPage, elog, ereport, errcode(), errmsg(), ERROR, LockBuffer(), makeRangeVarFromNameList(), NULL, palloc(), RBM_NORMAL, RelationData::rd_rel, ReadBufferExtended(), relation_close(), RELATION_IS_OTHER_TEMP, relation_openrv(), RelationGetNumberOfBlocks, RelationGetRelationName, ReleaseBuffer(), RELKIND_COMPOSITE_TYPE, RELKIND_FOREIGN_TABLE, RELKIND_VIEW, SET_VARSIZE, superuser(), textToQualifiedNameList(), VARDATA, and VARHDRSZ.
Referenced by get_raw_page(), and get_raw_page_fork().
{ bytea *raw_page; RangeVar *relrv; Relation rel; char *raw_page_data; Buffer buf; if (!superuser()) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("must be superuser to use raw functions")))); relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname)); rel = relation_openrv(relrv, AccessShareLock); /* Check that this relation has storage */ if (rel->rd_rel->relkind == RELKIND_VIEW) ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("cannot get raw page from view \"%s\"", RelationGetRelationName(rel)))); if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("cannot get raw page from composite type \"%s\"", RelationGetRelationName(rel)))); if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE) ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("cannot get raw page from foreign table \"%s\"", RelationGetRelationName(rel)))); /* * Reject attempts to read non-local temporary relations; we would be * likely to get wrong data since we have no visibility into the owning * session's local buffers. */ if (RELATION_IS_OTHER_TEMP(rel)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("cannot access temporary tables of other sessions"))); if (blkno >= RelationGetNumberOfBlocks(rel)) elog(ERROR, "block number %u is out of range for relation \"%s\"", blkno, RelationGetRelationName(rel)); /* Initialize buffer to copy to */ raw_page = (bytea *) palloc(BLCKSZ + VARHDRSZ); SET_VARSIZE(raw_page, BLCKSZ + VARHDRSZ); raw_page_data = VARDATA(raw_page); /* Take a verbatim copy of the page */ buf = ReadBufferExtended(rel, forknum, blkno, RBM_NORMAL, NULL); LockBuffer(buf, BUFFER_LOCK_SHARE); memcpy(raw_page_data, BufferGetPage(buf), BLCKSZ); LockBuffer(buf, BUFFER_LOCK_UNLOCK); ReleaseBuffer(buf); relation_close(rel, AccessShareLock); return raw_page; }
Datum page_header | ( | PG_FUNCTION_ARGS | ) |
Definition at line 169 of file rawpage.c.
References CStringGetTextDatum, elog, ereport, errcode(), errmsg(), ERROR, get_call_result_type(), heap_form_tuple(), HeapTupleGetDatum, NULL, PageGetLSN, PageGetPageLayoutVersion, PageGetPageSize, PageHeaderData::pd_checksum, PageHeaderData::pd_flags, PageHeaderData::pd_lower, PageHeaderData::pd_prune_xid, PageHeaderData::pd_special, PageHeaderData::pd_upper, PG_GETARG_BYTEA_P, PG_RETURN_DATUM, snprintf(), superuser(), TransactionIdGetDatum, UInt16GetDatum, values, VARDATA, and VARSIZE.
{ bytea *raw_page = PG_GETARG_BYTEA_P(0); int raw_page_size; TupleDesc tupdesc; Datum result; HeapTuple tuple; Datum values[9]; bool nulls[9]; PageHeader page; XLogRecPtr lsn; char lsnchar[64]; if (!superuser()) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("must be superuser to use raw page functions")))); raw_page_size = VARSIZE(raw_page) - VARHDRSZ; /* * Check that enough data was supplied, so that we don't try to access * fields outside the supplied buffer. */ if (raw_page_size < sizeof(PageHeaderData)) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("input page too small (%d bytes)", raw_page_size))); page = (PageHeader) VARDATA(raw_page); /* Build a tuple descriptor for our result type */ if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) elog(ERROR, "return type must be a row type"); /* Extract information from the page header */ lsn = PageGetLSN(page); snprintf(lsnchar, sizeof(lsnchar), "%X/%X", (uint32) (lsn >> 32), (uint32) lsn); values[0] = CStringGetTextDatum(lsnchar); values[1] = UInt16GetDatum(page->pd_checksum); values[2] = UInt16GetDatum(page->pd_flags); values[3] = UInt16GetDatum(page->pd_lower); values[4] = UInt16GetDatum(page->pd_upper); values[5] = UInt16GetDatum(page->pd_special); values[6] = UInt16GetDatum(PageGetPageSize(page)); values[7] = UInt16GetDatum(PageGetPageLayoutVersion(page)); values[8] = TransactionIdGetDatum(page->pd_prune_xid); /* Build and return the tuple. */ memset(nulls, 0, sizeof(nulls)); tuple = heap_form_tuple(tupdesc, values, nulls); result = HeapTupleGetDatum(tuple); PG_RETURN_DATUM(result); }
PG_FUNCTION_INFO_V1 | ( | page_header | ) |
PG_FUNCTION_INFO_V1 | ( | get_raw_page | ) |
PG_FUNCTION_INFO_V1 | ( | get_raw_page_fork | ) |