bootstrap.c

PostgreSQL7.4.6 for Linux

	elog(DEBUG4, "inserting column %d NULL", i);
	Assert(i >= 0 || i < MAXATTR);
	values[i] = PointerGetDatum(NULL);
	Blanks[i] = 'n';
}

#define MORE_THAN_THE_NUMBER_OF_CATALOGS 256

static bool
BootstrapAlreadySeen(Oid id)
{
	static Oid	seenArray[MORE_THAN_THE_NUMBER_OF_CATALOGS];
	static int	nseen = 0;
	bool		seenthis;
	int			i;

	seenthis = false;

	for (i = 0; i < nseen; i++)
	{
		if (seenArray[i] == id)
		{
			seenthis = true;
			break;
		}
	}
	if (!seenthis)
	{
		seenArray[nseen] = id;
		nseen++;
	}
	return seenthis;
}

/* ----------------
 *		cleanup
 * ----------------
 */
static void
cleanup(void)
{
	static int	beenhere = 0;

	if (!beenhere)
		beenhere = 1;
	else
	{
		elog(FATAL, "cleanup called twice");
		proc_exit(1);
	}
	if (boot_reldesc != NULL)
		closerel(NULL);
	CommitTransactionCommand();
	proc_exit(Warnings ? 1 : 0);
}

/* ----------------
 *		gettype
 *
 * NB: this is really ugly; it will return an integer index into Procid[],
 * and not an OID at all, until the first reference to a type not known in
 * Procid[].  At that point it will read and cache pg_type in the Typ array,
 * 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!
 * ----------------
 */
static Oid
gettype(char *type)
{
	int			i;
	Relation	rel;
	HeapScanDesc scan;
	HeapTuple	tup;
	struct typmap **app;

	if (Typ != (struct typmap **) NULL)
	{
		for (app = Typ; *app != (struct typmap *) NULL; app++)
		{
			if (strncmp(NameStr((*app)->am_typ.typname), type, NAMEDATALEN) == 0)
			{
				Ap = *app;
				return (*app)->am_oid;
			}
		}
	}
	else
	{
		for (i = 0; i < n_types; i++)
		{
			if (strncmp(type, Procid[i].name, NAMEDATALEN) == 0)
				return i;
		}
		elog(DEBUG4, "external type: %s", type);
		rel = heap_openr(TypeRelationName, NoLock);
		scan = heap_beginscan(rel, SnapshotNow, 0, (ScanKey) NULL);
		i = 0;
		while ((tup = heap_getnext(scan, ForwardScanDirection)) != NULL)
			++i;
		heap_endscan(scan);
		app = Typ = ALLOC(struct typmap *, i + 1);
		while (i-- > 0)
			*app++ = ALLOC(struct typmap, 1);
		*app = (struct typmap *) NULL;
		scan = heap_beginscan(rel, SnapshotNow, 0, (ScanKey) NULL);
		app = Typ;
		while ((tup = heap_getnext(scan, ForwardScanDirection)) != NULL)
		{
			(*app)->am_oid = HeapTupleGetOid(tup);
			memmove((char *) &(*app++)->am_typ,
					(char *) GETSTRUCT(tup),
					sizeof((*app)->am_typ));
		}
		heap_endscan(scan);
		heap_close(rel, NoLock);
		return gettype(type);
	}
	elog(ERROR, "unrecognized type \"%s\"", type);
	err_out();
	/* not reached, here to make compiler happy */
	return 0;
}

/* ----------------
 *		AllocateAttribute
 * ----------------
 */
static Form_pg_attribute
AllocateAttribute(void)
{
	Form_pg_attribute attribute = (Form_pg_attribute) malloc(ATTRIBUTE_TUPLE_SIZE);

	if (!PointerIsValid(attribute))
		elog(FATAL, "out of memory");
	MemSet(attribute, 0, ATTRIBUTE_TUPLE_SIZE);

	return attribute;
}

/* ----------------
 *		MapArrayTypeName
 * XXX arrays of "basetype" are always "_basetype".
 *	   this is an evil hack inherited from rel. 3.1.
 * XXX array dimension is thrown away because we
 *	   don't support fixed-dimension arrays.  again,
 *	   sickness from 3.1.
 *
 * the string passed in must have a '[' character in it
 *
 * the string returned is a pointer to static storage and should NOT
 * be freed by the CALLER.
 * ----------------
 */
char *
MapArrayTypeName(char *s)
{
	int			i,
				j;
	static char newStr[NAMEDATALEN];	/* array type names < NAMEDATALEN
										 * long */

	if (s == NULL || s[0] == '\0')
		return s;

	j = 1;
	newStr[0] = '_';
	for (i = 0; i < NAMEDATALEN - 1 && s[i] != '['; i++, j++)
		newStr[j] = s[i];

	newStr[j] = '\0';

	return newStr;
}

/* ----------------
 *		EnterString
 *		returns the string table position of the identifier
 *		passed to it.  We add it to the table if we can't find it.
 * ----------------
 */
int
EnterString(char *str)
{
	hashnode   *node;
	int			len;

	len = strlen(str);

	node = FindStr(str, len, 0);
	if (node)
		return node->strnum;
	else
	{
		node = AddStr(str, len, 0);
		return node->strnum;
	}
}

/* ----------------
 *		LexIDStr
 *		when given an idnum into the 'string-table' return the string
 *		associated with the idnum
 * ----------------
 */
char *
LexIDStr(int ident_num)
{
	return strtable[ident_num];
}


/* ----------------
 *		CompHash
 *
 *		Compute a hash function for a given string.  We look at the first,
 *		the last, and the middle character of a string to try to get spread
 *		the strings out.  The function is rather arbitrary, except that we
 *		are mod'ing by a prime number.
 * ----------------
 */
static int
CompHash(char *str, int len)
{
	int			result;

	result = (NUM * str[0] + NUMSQR * str[len - 1] + NUMCUBE * str[(len - 1) / 2]);

	return result % HASHTABLESIZE;

}

/* ----------------
 *		FindStr
 *
 *		This routine looks for the specified string in the hash
 *		table.	It returns a pointer to the hash node found,
 *		or NULL if the string is not in the table.
 * ----------------
 */
static hashnode *
FindStr(char *str, int length, hashnode *mderef)
{
	hashnode   *node;

	node = hashtable[CompHash(str, length)];
	while (node != NULL)
	{
		/*
		 * We must differentiate between string constants that might have
		 * the same value as a identifier and the identifier itself.
		 */
		if (!strcmp(str, strtable[node->strnum]))
		{
			return node;		/* no need to check */
		}
		else
			node = node->next;
	}
	/* Couldn't find it in the list */
	return NULL;
}

/* ----------------
 *		AddStr
 *
 *		This function adds the specified string, along with its associated
 *		data, to the hash table and the string table.  We return the node
 *		so that the calling routine can find out the unique id that AddStr
 *		has assigned to this string.
 * ----------------
 */
static hashnode *
AddStr(char *str, int strlength, int mderef)
{
	hashnode   *temp,
			   *trail,
			   *newnode;
	int			hashresult;
	int			len;

	if (++strtable_end >= STRTABLESIZE)
		elog(FATAL, "bootstrap string table overflow");

	/*
	 * Some of the utilites (eg, define type, create relation) assume that
	 * the string they're passed is a NAMEDATALEN.  We get array bound
	 * read violations from purify if we don't allocate at least
	 * NAMEDATALEN bytes for strings of this sort.	Because we're lazy, we
	 * allocate at least NAMEDATALEN bytes all the time.
	 */

	if ((len = strlength + 1) < NAMEDATALEN)
		len = NAMEDATALEN;

	strtable[strtable_end] = malloc((unsigned) len);
	strcpy(strtable[strtable_end], str);

	/* Now put a node in the hash table */

	newnode = (hashnode *) malloc(sizeof(hashnode) * 1);
	newnode->strnum = strtable_end;
	newnode->next = NULL;

	/* Find out where it goes */

	hashresult = CompHash(str, strlength);
	if (hashtable[hashresult] == NULL)
		hashtable[hashresult] = newnode;
	else
	{							/* There is something in the list */
		trail = hashtable[hashresult];
		temp = trail->next;
		while (temp != NULL)
		{
			trail = temp;
			temp = temp->next;
		}
		trail->next = newnode;
	}
	return newnode;
}



/*
 *	index_register() -- record an index that has been set up for building
 *						later.
 *
 *		At bootstrap time, we define a bunch of indices on system catalogs.
 *		We postpone actually building the indices until just before we're
 *		finished with initialization, however.	This is because more classes
 *		and indices may be defined, and we want to be sure that all of them
 *		are present in the index.
 */
void
index_register(Oid heap,
			   Oid ind,
			   IndexInfo *indexInfo)
{
	IndexList  *newind;
	MemoryContext oldcxt;

	/*
	 * XXX mao 10/31/92 -- don't gc index reldescs, associated info at
	 * bootstrap time.	we'll declare the indices now, but want to create
	 * them later.
	 */

	if (nogc == NULL)
		nogc = AllocSetContextCreate((MemoryContext) NULL,
									 "BootstrapNoGC",
									 ALLOCSET_DEFAULT_MINSIZE,
									 ALLOCSET_DEFAULT_INITSIZE,
									 ALLOCSET_DEFAULT_MAXSIZE);

	oldcxt = MemoryContextSwitchTo(nogc);

	newind = (IndexList *) palloc(sizeof(IndexList));
	newind->il_heap = heap;
	newind->il_ind = ind;
	newind->il_info = (IndexInfo *) palloc(sizeof(IndexInfo));

	memcpy(newind->il_info, indexInfo, sizeof(IndexInfo));
	/* expressions will likely be null, but may as well copy it */
	newind->il_info->ii_Expressions = (List *)
		copyObject(indexInfo->ii_Expressions);
	newind->il_info->ii_ExpressionsState = NIL;
	/* predicate will likely be null, but may as well copy it */
	newind->il_info->ii_Predicate = (List *)
		copyObject(indexInfo->ii_Predicate);
	newind->il_info->ii_PredicateState = NIL;

	newind->il_next = ILHead;
	ILHead = newind;

	MemoryContextSwitchTo(oldcxt);
}

void
build_indices()
{
	for (; ILHead != (IndexList *) NULL; ILHead = ILHead->il_next)
	{
		Relation	heap;
		Relation	ind;

		heap = heap_open(ILHead->il_heap, NoLock);
		ind = index_open(ILHead->il_ind);
		index_build(heap, ind, ILHead->il_info);

		/*
		 * In normal processing mode, index_build would close the heap and
		 * index, but in bootstrap mode it will not.
		 */

		/*
		 * All of the rest of this routine is needed only because in
		 * bootstrap processing we don't increment xact id's.  The normal
		 * DefineIndex code replaces a pg_class tuple with updated info
		 * including the relhasindex flag (which we need to have updated).
		 * Unfortunately, there are always two indices defined on each
		 * catalog causing us to update the same pg_class tuple twice for
		 * each catalog getting an index during bootstrap resulting in the
		 * ghost tuple problem (see heap_update).	To get around this we
		 * change the relhasindex field ourselves in this routine keeping
		 * track of what catalogs we already changed so that we don't
		 * modify those tuples twice.  The normal mechanism for updating
		 * pg_class is disabled during bootstrap.
		 *
		 * -mer
		 */
		if (!BootstrapAlreadySeen(RelationGetRelid(heap)))
			UpdateStats(RelationGetRelid(heap), 0);

		/* XXX Probably we ought to close the heap and index here? */
	}
}