Import BSDDB 4.7.25 (as of svn r89086)

2017-09-04 13:40:25 -05:00
parent 4b29e0458f
commit 8f590873d0
4781 changed files with 2241032 additions and 6 deletions
--- a/db/db_ret.c
+++ b/db/db_ret.c
@@ -0,0 +1,155 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996,2008 Oracle.  All rights reserved.
+ *
+ * $Id: db_ret.c 63573 2008-05-23 21:43:21Z trent.nelson $
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+#include "dbinc/db_page.h"
+#include "dbinc/db_am.h"
+
+/*
+ * __db_ret --
+ *	Build return DBT.
+ *
+ * PUBLIC: int __db_ret __P((DB *, DB_THREAD_INFO *, DB_TXN *,
+ * PUBLIC:    PAGE *, u_int32_t, DBT *, void **, u_int32_t *));
+ */
+int
+__db_ret(dbp, ip, txn, h, indx, dbt, memp, memsize)
+	DB *dbp;
+	DB_THREAD_INFO *ip;
+	DB_TXN *txn;
+	PAGE *h;
+	u_int32_t indx;
+	DBT *dbt;
+	void **memp;
+	u_int32_t *memsize;
+{
+	BKEYDATA *bk;
+	BOVERFLOW *bo;
+	HOFFPAGE ho;
+	u_int32_t len;
+	u_int8_t *hk;
+	void *data;
+
+	switch (TYPE(h)) {
+	case P_HASH_UNSORTED:
+	case P_HASH:
+		hk = P_ENTRY(dbp, h, indx);
+		if (HPAGE_PTYPE(hk) == H_OFFPAGE) {
+			memcpy(&ho, hk, sizeof(HOFFPAGE));
+			return (__db_goff(dbp, ip, txn, dbt,
+			    ho.tlen, ho.pgno, memp, memsize));
+		}
+		len = LEN_HKEYDATA(dbp, h, dbp->pgsize, indx);
+		data = HKEYDATA_DATA(hk);
+		break;
+	case P_LBTREE:
+	case P_LDUP:
+	case P_LRECNO:
+		bk = GET_BKEYDATA(dbp, h, indx);
+		if (B_TYPE(bk->type) == B_OVERFLOW) {
+			bo = (BOVERFLOW *)bk;
+			return (__db_goff(dbp, ip, txn, dbt,
+			    bo->tlen, bo->pgno, memp, memsize));
+		}
+		len = bk->len;
+		data = bk->data;
+		break;
+	default:
+		return (__db_pgfmt(dbp->env, h->pgno));
+	}
+
+	return (__db_retcopy(dbp->env, dbt, data, len, memp, memsize));
+}
+
+/*
+ * __db_retcopy --
+ *	Copy the returned data into the user's DBT, handling special flags.
+ *
+ * PUBLIC: int __db_retcopy __P((ENV *, DBT *,
+ * PUBLIC:    void *, u_int32_t, void **, u_int32_t *));
+ */
+int
+__db_retcopy(env, dbt, data, len, memp, memsize)
+	ENV *env;
+	DBT *dbt;
+	void *data;
+	u_int32_t len;
+	void **memp;
+	u_int32_t *memsize;
+{
+	int ret;
+
+	ret = 0;
+
+	/* If returning a partial record, reset the length. */
+	if (F_ISSET(dbt, DB_DBT_PARTIAL)) {
+		data = (u_int8_t *)data + dbt->doff;
+		if (len > dbt->doff) {
+			len -= dbt->doff;
+			if (len > dbt->dlen)
+				len = dbt->dlen;
+		} else
+			len = 0;
+	}
+
+	/*
+	 * Allocate memory to be owned by the application: DB_DBT_MALLOC,
+	 * DB_DBT_REALLOC.
+	 *
+	 * !!!
+	 * We always allocate memory, even if we're copying out 0 bytes. This
+	 * guarantees consistency, i.e., the application can always free memory
+	 * without concern as to how many bytes of the record were requested.
+	 *
+	 * Use the memory specified by the application: DB_DBT_USERMEM.
+	 *
+	 * !!!
+	 * If the length we're going to copy is 0, the application-supplied
+	 * memory pointer is allowed to be NULL.
+	 */
+	if (F_ISSET(dbt, DB_DBT_USERCOPY)) {
+		dbt->size = len;
+		return (len == 0 ? 0 : env->dbt_usercopy(dbt, 0, data,
+		    len, DB_USERCOPY_SETDATA));
+
+	} else if (F_ISSET(dbt, DB_DBT_MALLOC))
+		ret = __os_umalloc(env, len, &dbt->data);
+	else if (F_ISSET(dbt, DB_DBT_REALLOC)) {
+		if (dbt->data == NULL || dbt->size == 0 || dbt->size < len)
+			ret = __os_urealloc(env, len, &dbt->data);
+	} else if (F_ISSET(dbt, DB_DBT_USERMEM)) {
+		if (len != 0 && (dbt->data == NULL || dbt->ulen < len))
+			ret = DB_BUFFER_SMALL;
+	} else if (memp == NULL || memsize == NULL)
+		ret = EINVAL;
+	else {
+		if (len != 0 && (*memsize == 0 || *memsize < len)) {
+			if ((ret = __os_realloc(env, len, memp)) == 0)
+				*memsize = len;
+			else
+				*memsize = 0;
+		}
+		if (ret == 0)
+			dbt->data = *memp;
+	}
+
+	if (ret == 0 && len != 0)
+		memcpy(dbt->data, data, len);
+
+	/*
+	 * Return the length of the returned record in the DBT size field.
+	 * This satisfies the requirement that if we're using user memory
+	 * and insufficient memory was provided, return the amount necessary
+	 * in the size field.
+	 */
+	dbt->size = len;
+
+	return (ret);
+}