mirror of
https://github.com/postgres/postgres.git
synced 2025-11-13 16:22:44 +03:00
Postgres95 1.01 Distribution - Virgin Sources
This commit is contained in:
Marc G. Fournier
323
src/backend/libpq/be-dumpdata.c
Normal file
323
src/backend/libpq/be-dumpdata.c
Normal file
@@ -0,0 +1,323 @@
|
||||
/*-------------------------------------------------------------------------
|
||||
*
|
||||
* be-dumpdata.c--
|
||||
* support for collection of returned tuples from an internal
|
||||
* PQ call into a backend buffer.
|
||||
*
|
||||
* Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/libpq/Attic/be-dumpdata.c,v 1.1.1.1 1996/07/09 06:21:30 scrappy Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
/*
|
||||
* INTERFACE ROUTINES
|
||||
* be_portalinit - initialize backend portal administration
|
||||
* be_portalpush - add a portal to the top of the portal stack
|
||||
* be_portalpop - remove portal on the top of the stack & return it
|
||||
* be_currentportal - return the top portal on the portal stack
|
||||
* be_newportal - return a new portal.
|
||||
* be_portalinit - initialize backend portal expected to hold results.
|
||||
* be_printtup - add a tuple to a backend portal
|
||||
*
|
||||
* NOTES
|
||||
* Since backend user-defined operators can call queries
|
||||
* which in turn call user-defined operators can call queries...
|
||||
* we have to keep track of portals on a stack. BeginCommand()
|
||||
* puts portals on the stack and the PQ functions remove them.
|
||||
*
|
||||
*/
|
||||
#include "postgres.h"
|
||||
|
||||
#include "lib/dllist.h"
|
||||
#include "libpq/libpq-be.h"
|
||||
|
||||
#include "access/heapam.h"
|
||||
#include "access/htup.h"
|
||||
#include "storage/buf.h"
|
||||
#include "utils/memutils.h"
|
||||
#include "utils/palloc.h"
|
||||
#include "fmgr.h"
|
||||
#include "utils/mcxt.h"
|
||||
#include "utils/elog.h"
|
||||
#include "utils/exc.h"
|
||||
|
||||
#include "utils/syscache.h"
|
||||
#include "catalog/pg_type.h"
|
||||
#include "catalog/catalog.h"
|
||||
#include "access/printtup.h"
|
||||
|
||||
/* ----------------
|
||||
* backend portal stack for recursive PQexec calls
|
||||
* ----------------
|
||||
*/
|
||||
static Dllist *be_portalstack;
|
||||
|
||||
/* ----------------
|
||||
* be_portalinit - initialize backend portal administration
|
||||
*
|
||||
* This is called once from InitPostgres() to initialize
|
||||
* the portal stack.
|
||||
* ----------------
|
||||
*/
|
||||
void
|
||||
be_portalinit()
|
||||
{
|
||||
be_portalstack = DLNewList();
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_portalpush - add a portal to the top of the portal stack
|
||||
*
|
||||
* used by BeginCommand()
|
||||
* ----------------
|
||||
*/
|
||||
void
|
||||
be_portalpush(PortalEntry *entry)
|
||||
{
|
||||
DLAddTail(be_portalstack, DLNewElem(entry));
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_portalpop - remove the portal on the top of the stack & return it
|
||||
*
|
||||
* used by PQexec()
|
||||
* ----------------
|
||||
*/
|
||||
PortalEntry *
|
||||
be_portalpop()
|
||||
{
|
||||
PortalEntry *p;
|
||||
Dlelem* elt;
|
||||
elt = DLRemTail(be_portalstack);
|
||||
|
||||
p = (elt ? (PortalEntry*)DLE_VAL(elt) : NULL);
|
||||
DLFreeElem(elt);
|
||||
return p;
|
||||
|
||||
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_currentportal - return the top portal on the portal stack
|
||||
*
|
||||
* used by be_printtup()
|
||||
* ----------------
|
||||
*/
|
||||
PortalEntry *
|
||||
be_currentportal()
|
||||
{
|
||||
Dlelem* elt;
|
||||
elt = DLGetTail(be_portalstack);
|
||||
return (elt ? (PortalEntry*)DLE_VAL(elt) : NULL);
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_newportal - return a new portal.
|
||||
*
|
||||
* If the user-defined function does not specify a portal name,
|
||||
* we generate a unique one. Names are generated from a combination
|
||||
* of a postgres oid and an integer counter which is incremented
|
||||
* every time we ask for a local portal.
|
||||
*
|
||||
* used by BeginCommand()
|
||||
* ----------------
|
||||
*/
|
||||
|
||||
static Oid be_portaloid;
|
||||
static u_int be_portalcnt = 0;
|
||||
|
||||
PortalEntry *
|
||||
be_newportal()
|
||||
{
|
||||
PortalEntry *entry;
|
||||
char buf[PortalNameLength];
|
||||
|
||||
/* ----------------
|
||||
* generate a new name
|
||||
* ----------------
|
||||
*/
|
||||
if (be_portalcnt == 0)
|
||||
be_portaloid = newoid();
|
||||
be_portalcnt++;
|
||||
sprintf(buf, "be_%d_%d", be_portaloid, be_portalcnt);
|
||||
|
||||
/* ----------------
|
||||
* initialize the new portal entry and keep track
|
||||
* of the current memory context for be_printtup().
|
||||
* This is important - otherwise whatever we allocate
|
||||
* will go away and the contents of the portal after
|
||||
* PQexec() returns will be meaningless.
|
||||
* ----------------
|
||||
*/
|
||||
entry = pbuf_setup(buf);
|
||||
entry->portalcxt = (Pointer) CurrentMemoryContext;
|
||||
|
||||
return entry;
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_typeinit - initialize backend portal expected to hold
|
||||
* query results.
|
||||
*
|
||||
* used by BeginCommand()
|
||||
* ----------------
|
||||
*/
|
||||
void
|
||||
be_typeinit(PortalEntry *entry,
|
||||
TupleDesc tupDesc,
|
||||
int natts)
|
||||
{
|
||||
PortalBuffer *portal;
|
||||
GroupBuffer *group;
|
||||
int i;
|
||||
AttributeTupleForm *attrs = tupDesc->attrs;
|
||||
|
||||
/* ----------------
|
||||
* add a new portal group to the portal
|
||||
* ----------------
|
||||
*/
|
||||
portal = entry->portal;
|
||||
portal->no_groups++;
|
||||
portal->groups = group = pbuf_addGroup(portal);
|
||||
group->no_fields = natts;
|
||||
|
||||
/* ----------------
|
||||
* initialize portal group type info
|
||||
* ----------------
|
||||
*/
|
||||
if (natts > 0) {
|
||||
group->types = pbuf_addTypes(natts);
|
||||
for (i = 0; i < natts; ++i) {
|
||||
strncpy(group->types[i].name, attrs[i]->attname.data, NAMEDATALEN);
|
||||
group->types[i].adtid = attrs[i]->atttypid;
|
||||
group->types[i].adtsize = attrs[i]->attlen;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* be_printtup - add a tuple to a backend portal
|
||||
*
|
||||
* used indirectly by ExecRetrieve()
|
||||
*
|
||||
* This code is pretty much copied from printtup(), dump_type()
|
||||
* and dump_data(). -cim 2/12/91
|
||||
* ----------------
|
||||
*/
|
||||
void
|
||||
be_printtup(HeapTuple tuple, TupleDesc typeinfo)
|
||||
{
|
||||
int i;
|
||||
char *attr;
|
||||
bool isnull;
|
||||
Oid typoutput;
|
||||
|
||||
PortalEntry *entry = NULL;
|
||||
PortalBuffer *portal = NULL;
|
||||
GroupBuffer *group = NULL ;
|
||||
TupleBlock *tuples = NULL;
|
||||
char **values;
|
||||
int *lengths;
|
||||
|
||||
MemoryContext savecxt;
|
||||
|
||||
/* ----------------
|
||||
* get the current portal and group
|
||||
* ----------------
|
||||
*/
|
||||
entry = be_currentportal();
|
||||
portal = entry->portal;
|
||||
group = portal->groups;
|
||||
|
||||
/* ----------------
|
||||
* switch to the portal's memory context so that
|
||||
* the tuples we allocate are returned to the user.
|
||||
* ----------------
|
||||
*/
|
||||
savecxt = MemoryContextSwitchTo((MemoryContext)entry->portalcxt);
|
||||
|
||||
/* ----------------
|
||||
* If no tuple block yet, allocate one.
|
||||
* If the current block is full, allocate another one.
|
||||
* ----------------
|
||||
*/
|
||||
if (group->tuples == NULL) {
|
||||
tuples = group->tuples = pbuf_addTuples();
|
||||
tuples->tuple_index = 0;
|
||||
} else {
|
||||
tuples = group->tuples;
|
||||
/* walk to the end of the linked list of TupleBlocks */
|
||||
while (tuples->next)
|
||||
tuples = tuples->next;
|
||||
/* now, tuples is the last TupleBlock, check to see if it is full.
|
||||
If so, allocate a new TupleBlock and add it to the end of
|
||||
the chain */
|
||||
|
||||
if (tuples->tuple_index == TupleBlockSize) {
|
||||
tuples->next = pbuf_addTuples();
|
||||
tuples = tuples->next;
|
||||
tuples->tuple_index = 0;
|
||||
}
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* Allocate space for a tuple.
|
||||
* ----------------
|
||||
*/
|
||||
tuples->values[tuples->tuple_index] = pbuf_addTuple(tuple->t_natts);
|
||||
tuples->lengths[tuples->tuple_index] = pbuf_addTupleValueLengths(tuple->t_natts);
|
||||
/* ----------------
|
||||
* copy printable representations of the tuple's attributes
|
||||
* to the portal.
|
||||
*
|
||||
* This seems silly, because the user's function which is calling
|
||||
* PQexec() or PQfn() will probably just convert this back into the
|
||||
* internal form anyways, but the point here is to provide a uniform
|
||||
* libpq interface and this is how the fe libpq interface currently
|
||||
* works. Pretty soon we'll have to add code to let the fe or be
|
||||
* select the desired data representation and then deal with that.
|
||||
* This should not be too hard, as there already exist typrecieve()
|
||||
* and typsend() procedures for user-defined types (see pg_type.h)
|
||||
* -cim 2/11/91
|
||||
* ----------------
|
||||
*/
|
||||
|
||||
values = tuples->values[tuples->tuple_index];
|
||||
lengths = tuples->lengths[tuples->tuple_index];
|
||||
|
||||
for (i = 0; i < tuple->t_natts; i++) {
|
||||
attr = heap_getattr(tuple, InvalidBuffer, i+1, typeinfo, &isnull);
|
||||
typoutput = typtoout((Oid) typeinfo->attrs[i]->atttypid);
|
||||
|
||||
lengths[i] = typeinfo->attrs[i]->attlen;
|
||||
|
||||
if (lengths[i] == -1) /* variable length attribute */
|
||||
if (!isnull)
|
||||
lengths[i] = VARSIZE(attr)-VARHDRSZ;
|
||||
else
|
||||
lengths[i] = 0;
|
||||
|
||||
if (!isnull && OidIsValid(typoutput)) {
|
||||
values[i] = fmgr(typoutput, attr, gettypelem(typeinfo->attrs[i]->atttypid));
|
||||
} else
|
||||
values[i] = NULL;
|
||||
|
||||
}
|
||||
|
||||
/* ----------------
|
||||
* increment tuple group counters
|
||||
* ----------------
|
||||
*/
|
||||
portal->no_tuples++;
|
||||
group->no_tuples++;
|
||||
tuples->tuple_index++;
|
||||
|
||||
/* ----------------
|
||||
* return to the original memory context
|
||||
* ----------------
|
||||
*/
|
||||
MemoryContextSwitchTo(savecxt);
|
||||
}
|
||||
Reference in New Issue
Block a user