bootstrap.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

			attrtypes[i] = AllocateAttribute();
		memmove((char *) attrtypes[i],
				(char *) boot_reldesc->rd_att->attrs[i],
				ATTRIBUTE_TUPLE_SIZE);

		{
			Form_pg_attribute at = attrtypes[i];

			elog(DEBUG4, "create attribute %d name %s len %d num %d type %u",
				 i, NameStr(at->attname), at->attlen, at->attnum,
				 at->atttypid);
		}
	}
}

/* ----------------
 *		closerel
 * ----------------
 */
void
closerel(char *name)
{
	if (name)
	{
		if (boot_reldesc)
		{
			if (strcmp(RelationGetRelationName(boot_reldesc), name) != 0)
				elog(ERROR, "close of %s when %s was expected",
					 name, RelationGetRelationName(boot_reldesc));
		}
		else
			elog(ERROR, "close of %s before any relation was opened",
				 name);
	}

	if (boot_reldesc == NULL)
		elog(ERROR, "no open relation to close");
	else
	{
		elog(DEBUG4, "close relation %s",
			 RelationGetRelationName(boot_reldesc));
		heap_close(boot_reldesc, NoLock);
		boot_reldesc = NULL;
	}
}



/* ----------------
 * DEFINEATTR()
 *
 * define a <field,type> pair
 * if there are n fields in a relation to be created, this routine
 * will be called n times
 * ----------------
 */
void
DefineAttr(char *name, char *type, int attnum)
{
	Oid			typeoid;

	if (boot_reldesc != NULL)
	{
		elog(WARNING, "no open relations allowed with CREATE command");
		closerel(NULL);
	}

	if (attrtypes[attnum] == NULL)
		attrtypes[attnum] = AllocateAttribute();
	MemSet(attrtypes[attnum], 0, ATTRIBUTE_TUPLE_SIZE);

	namestrcpy(&attrtypes[attnum]->attname, name);
	elog(DEBUG4, "column %s %s", NameStr(attrtypes[attnum]->attname), type);
	attrtypes[attnum]->attnum = attnum + 1;		/* fillatt */

	typeoid = gettype(type);

	if (Typ != NULL)
	{
		attrtypes[attnum]->atttypid = Ap->am_oid;
		attrtypes[attnum]->attlen = Ap->am_typ.typlen;
		attrtypes[attnum]->attbyval = Ap->am_typ.typbyval;
		attrtypes[attnum]->attstorage = Ap->am_typ.typstorage;
		attrtypes[attnum]->attalign = Ap->am_typ.typalign;
		/* if an array type, assume 1-dimensional attribute */
		if (Ap->am_typ.typelem != InvalidOid && Ap->am_typ.typlen < 0)
			attrtypes[attnum]->attndims = 1;
		else
			attrtypes[attnum]->attndims = 0;
	}
	else
	{
		attrtypes[attnum]->atttypid = TypInfo[typeoid].oid;
		attrtypes[attnum]->attlen = TypInfo[typeoid].len;
		attrtypes[attnum]->attbyval = TypInfo[typeoid].byval;
		attrtypes[attnum]->attstorage = TypInfo[typeoid].storage;
		attrtypes[attnum]->attalign = TypInfo[typeoid].align;
		/* if an array type, assume 1-dimensional attribute */
		if (TypInfo[typeoid].elem != InvalidOid &&
			attrtypes[attnum]->attlen < 0)
			attrtypes[attnum]->attndims = 1;
		else
			attrtypes[attnum]->attndims = 0;
	}

	attrtypes[attnum]->attstattarget = -1;
	attrtypes[attnum]->attcacheoff = -1;
	attrtypes[attnum]->atttypmod = -1;
	attrtypes[attnum]->attislocal = true;

	/*
	 * Mark as "not null" if type is fixed-width and prior columns are too.
	 * This corresponds to case where column can be accessed directly via C
	 * struct declaration.
	 *
	 * oidvector and int2vector are also treated as not-nullable, even though
	 * they are no longer fixed-width.
	 */
#define MARKNOTNULL(att) \
	((att)->attlen > 0 || \
	 (att)->atttypid == OIDVECTOROID || \
	 (att)->atttypid == INT2VECTOROID)

	if (MARKNOTNULL(attrtypes[attnum]))
	{
		int			i;

		for (i = 0; i < attnum; i++)
		{
			if (!MARKNOTNULL(attrtypes[i]))
				break;
		}
		if (i == attnum)
			attrtypes[attnum]->attnotnull = true;
	}
}


/* ----------------
 *		InsertOneTuple
 *
 * If objectid is not zero, it is a specific OID to assign to the tuple.
 * Otherwise, an OID will be assigned (if necessary) by heap_insert.
 * ----------------
 */
void
InsertOneTuple(Oid objectid)
{
	HeapTuple	tuple;
	TupleDesc	tupDesc;
	int			i;

	elog(DEBUG4, "inserting row oid %u, %d columns", objectid, numattr);

	tupDesc = CreateTupleDesc(numattr,
							  RelationGetForm(boot_reldesc)->relhasoids,
							  attrtypes);
	tuple = heap_formtuple(tupDesc, values, Blanks);
	if (objectid != (Oid) 0)
		HeapTupleSetOid(tuple, objectid);
	pfree(tupDesc);				/* just free's tupDesc, not the attrtypes */

	simple_heap_insert(boot_reldesc, tuple);
	heap_freetuple(tuple);
	elog(DEBUG4, "row inserted");

	/*
	 * Reset blanks for next tuple
	 */
	for (i = 0; i < numattr; i++)
		Blanks[i] = ' ';
}

/* ----------------
 *		InsertOneValue
 * ----------------
 */
void
InsertOneValue(char *value, int i)
{
	Oid			typoid;
	Oid			typioparam;
	Oid			typinput;
	Oid			typoutput;
	char	   *prt;

	AssertArg(i >= 0 || i < MAXATTR);

	elog(DEBUG4, "inserting column %d value \"%s\"", i, value);

	if (Typ != NULL)
	{
		struct typmap **app;
		struct typmap *ap;

		elog(DEBUG5, "Typ != NULL");
		typoid = boot_reldesc->rd_att->attrs[i]->atttypid;
		app = Typ;
		while (*app && (*app)->am_oid != typoid)
			++app;
		ap = *app;
		if (ap == NULL)
			elog(ERROR, "could not find atttypid %u in Typ list", typoid);

		/* XXX this should match getTypeIOParam() */
		if (ap->am_typ.typtype == 'c')
			typioparam = typoid;
		else
			typioparam = ap->am_typ.typelem;

		typinput = ap->am_typ.typinput;
		typoutput = ap->am_typ.typoutput;
	}
	else
	{
		int			typeindex;

		/* XXX why is typoid determined differently in this path? */
		typoid = attrtypes[i]->atttypid;
		for (typeindex = 0; typeindex < n_types; typeindex++)
		{
			if (TypInfo[typeindex].oid == typoid)
				break;
		}
		if (typeindex >= n_types)
			elog(ERROR, "type oid %u not found", typoid);
		elog(DEBUG5, "Typ == NULL, typeindex = %u", typeindex);

		/* XXX there are no composite types in TypInfo */
		typioparam = TypInfo[typeindex].elem;

		typinput = TypInfo[typeindex].inproc;
		typoutput = TypInfo[typeindex].outproc;
	}

	values[i] = OidFunctionCall3(typinput,
								 CStringGetDatum(value),
								 ObjectIdGetDatum(typioparam),
								 Int32GetDatum(-1));
	prt = DatumGetCString(OidFunctionCall1(typoutput,
										   values[i]));
	elog(DEBUG4, "inserted -> %s", prt);
	pfree(prt);
}

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

/* ----------------
 *		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 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,
 * 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 != NULL)
	{
		for (app = Typ; *app != 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, TypInfo[i].name, NAMEDATALEN) == 0)
				return i;
		}
		elog(DEBUG4, "external type: %s", type);
		rel = heap_open(TypeRelationId, NoLock);
		scan = heap_beginscan(rel, SnapshotNow, 0, 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 = NULL;
		scan = heap_beginscan(rel, SnapshotNow, 0, 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, NULL);
	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(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(void)
{
	for (; ILHead != 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.
		 */

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