public inbox for [email protected]  
help / color / mirror / Atom feed
[PATCH 1/4] bootstrap: convert Typ to a List*
2+ messages / 2 participants
[nested] [flat]

* [PATCH 1/4] bootstrap: convert Typ to a List*
@ 2020-11-20 02:48  Justin Pryzby <[email protected]>
  0 siblings, 0 replies; 2+ messages in thread

From: Justin Pryzby @ 2020-11-20 02:48 UTC (permalink / raw)

---
 src/backend/bootstrap/bootstrap.c | 89 ++++++++++++++-----------------
 1 file changed, 41 insertions(+), 48 deletions(-)

diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 6f615e6622..1b940d9d27 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -58,7 +58,7 @@ static void BootstrapModeMain(void);
 static void bootstrap_signals(void);
 static void ShutdownAuxiliaryProcess(int code, Datum arg);
 static Form_pg_attribute AllocateAttribute(void);
-static void populate_typ_array(void);
+static void populate_typ(void);
 static Oid	gettype(char *type);
 static void cleanup(void);
 
@@ -159,7 +159,7 @@ struct typmap
 	FormData_pg_type am_typ;
 };
 
-static struct typmap **Typ = NULL;
+static List *Typ = NIL; /* List of struct typmap* */
 static struct typmap *Ap = NULL;
 
 static Datum values[MAXATTR];	/* current row's attribute values */
@@ -595,10 +595,10 @@ boot_openrel(char *relname)
 
 	/*
 	 * pg_type must be filled before any OPEN command is executed, hence we
-	 * can now populate the Typ array if we haven't yet.
+	 * can now populate Typ if we haven't yet.
 	 */
-	if (Typ == NULL)
-		populate_typ_array();
+	if (Typ == NIL)
+		populate_typ();
 
 	if (boot_reldesc != NULL)
 		closerel(NULL);
@@ -688,7 +688,7 @@ DefineAttr(char *name, char *type, int attnum, int nullness)
 
 	typeoid = gettype(type);
 
-	if (Typ != NULL)
+	if (Typ != NIL)
 	{
 		attrtypes[attnum]->atttypid = Ap->am_oid;
 		attrtypes[attnum]->attlen = Ap->am_typ.typlen;
@@ -866,47 +866,36 @@ cleanup(void)
 }
 
 /* ----------------
- *		populate_typ_array
+ *		populate_typ
  *
- * Load the Typ array by reading pg_type.
+ * Load Typ by reading pg_type.
  * ----------------
  */
 static void
-populate_typ_array(void)
+populate_typ(void)
 {
 	Relation	rel;
 	TableScanDesc scan;
 	HeapTuple	tup;
-	int			nalloc;
-	int			i;
-
-	Assert(Typ == NULL);
+	MemoryContext old;
 
-	nalloc = 512;
-	Typ = (struct typmap **)
-		MemoryContextAlloc(TopMemoryContext, nalloc * sizeof(struct typmap *));
+	Assert(Typ == NIL);
 
 	rel = table_open(TypeRelationId, NoLock);
 	scan = table_beginscan_catalog(rel, 0, NULL);
-	i = 0;
+	old = MemoryContextSwitchTo(TopMemoryContext);
 	while ((tup = heap_getnext(scan, ForwardScanDirection)) != NULL)
 	{
 		Form_pg_type typForm = (Form_pg_type) GETSTRUCT(tup);
+		struct typmap *newtyp;
 
-		/* make sure there will be room for a trailing NULL pointer */
-		if (i >= nalloc - 1)
-		{
-			nalloc *= 2;
-			Typ = (struct typmap **)
-				repalloc(Typ, nalloc * sizeof(struct typmap *));
-		}
-		Typ[i] = (struct typmap *)
-			MemoryContextAlloc(TopMemoryContext, sizeof(struct typmap));
-		Typ[i]->am_oid = typForm->oid;
-		memcpy(&(Typ[i]->am_typ), typForm, sizeof(Typ[i]->am_typ));
-		i++;
+		newtyp = (struct typmap *) palloc(sizeof(struct typmap));
+		Typ = lappend(Typ, newtyp);
+
+		newtyp->am_oid = typForm->oid;
+		memcpy(&newtyp->am_typ, typForm, sizeof(newtyp->am_typ));
 	}
-	Typ[i] = NULL;				/* Fill trailing NULL pointer */
+	MemoryContextSwitchTo(old);
 	table_endscan(scan);
 	table_close(rel, NoLock);
 }
@@ -916,25 +905,26 @@ populate_typ_array(void)
  *
  * NB: this is really ugly; it will return an integer index into TypInfo[],
  * and not an OID at all, until the first reference to a type not known in
- * TypInfo[].  At that point it will read and cache pg_type in the Typ array,
+ * TypInfo[].  At that point it will read and cache pg_type in Typ,
  * and subsequently return a real OID (and set the global pointer Ap to
  * point at the found row in Typ).  So caller must check whether Typ is
- * still NULL to determine what the return value is!
+ * still NIL to determine what the return value is!
  * ----------------
  */
 static Oid
 gettype(char *type)
 {
-	if (Typ != NULL)
+	if (Typ != NIL)
 	{
-		struct typmap **app;
+		ListCell *lc;
 
-		for (app = Typ; *app != NULL; app++)
+		foreach (lc, Typ)
 		{
-			if (strncmp(NameStr((*app)->am_typ.typname), type, NAMEDATALEN) == 0)
+			struct typmap *app = lfirst(lc);
+			if (strncmp(NameStr(app->am_typ.typname), type, NAMEDATALEN) == 0)
 			{
-				Ap = *app;
-				return (*app)->am_oid;
+				Ap = app;
+				return app->am_oid;
 			}
 		}
 	}
@@ -949,7 +939,7 @@ gettype(char *type)
 		}
 		/* Not in TypInfo, so we'd better be able to read pg_type now */
 		elog(DEBUG4, "external type: %s", type);
-		populate_typ_array();
+		populate_typ();
 		return gettype(type);
 	}
 	elog(ERROR, "unrecognized type \"%s\"", type);
@@ -977,17 +967,20 @@ boot_get_type_io_data(Oid typid,
 					  Oid *typinput,
 					  Oid *typoutput)
 {
-	if (Typ != NULL)
+	if (Typ != NIL)
 	{
 		/* We have the boot-time contents of pg_type, so use it */
-		struct typmap **app;
-		struct typmap *ap;
-
-		app = Typ;
-		while (*app && (*app)->am_oid != typid)
-			++app;
-		ap = *app;
-		if (ap == NULL)
+		struct typmap *ap = NULL;
+		ListCell *lc;
+
+		foreach (lc, Typ)
+		{
+			ap = lfirst(lc);
+			if (ap->am_oid == typid)
+				break;
+		}
+
+		if (!ap || ap->am_oid != typid)
 			elog(ERROR, "type OID %u not found in Typ list", typid);
 
 		*typlen = ap->am_typ.typlen;
-- 
2.26.2


--------------BCA1373AE29B32B57608F4EE
Content-Type: text/x-patch; charset=UTF-8;
 name="0002-Allow-composite-types-in-bootstrap-20210307.patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
 filename="0002-Allow-composite-types-in-bootstrap-20210307.patch"



^ permalink  raw  reply  [nested|flat] 2+ messages in thread

* Re: Control your disk usage in PG: Introduction to Disk Quota Extension
@ 2024-02-26 22:38  Stephen Frost <[email protected]>
  0 siblings, 0 replies; 2+ messages in thread

From: Stephen Frost @ 2024-02-26 22:38 UTC (permalink / raw)
  To: Xing Guo <[email protected]>; +Cc: Daniel Gustafsson <[email protected]>; Haozhou Wang <[email protected]>; David Steele <[email protected]>; Michael Paquier <[email protected]>; Alvaro Herrera <[email protected]>; Hubert Zhang <[email protected]>; Thomas Munro <[email protected]>; Andres Freund <[email protected]>; Robert Haas <[email protected]>; pgsql-hackers; Tomas Vondra <[email protected]>; Heikki Linnakangas <[email protected]>

Greetings,

* Xing Guo ([email protected]) wrote:
> Looks that many hackers are happy with the original patch except that
> the original patch needs a simple rebase, though it has been 3 years.

I'm not completely against the idea of adding these hooks, but I have to
say that it's unfortunate to imagine having to use an extension for
something like quotas as it's really something that would ideally be in
core.

> Shall we push forward this patch so that it can benefit extensions not
> only diskquota?

Would be great to hear about other use-cases for these hooks, which
would also help us be comfortable that these are the right hooks to
introduce with the correct arguments.  What are the other extensions
that you're referring to here..?

Thanks,

Stephen


Attachments:

  [application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc)
  download

^ permalink  raw  reply  [nested|flat] 2+ messages in thread


end of thread, other threads:[~2024-02-26 22:38 UTC | newest]

Thread overview: 2+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2020-11-20 02:48 [PATCH 1/4] bootstrap: convert Typ to a List* Justin Pryzby <[email protected]>
2024-02-26 22:38 Re: Control your disk usage in PG: Introduction to Disk Quota Extension Stephen Frost <[email protected]>

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox