Clean up some undo page accessor functions

trx_undo_page_get_prev_rec(), trx_undo_page_get_last_rec(),
trx_undo_page_get_first_rec(), trx_undo_page_get_start():
Move to the only caller, trx0undo.cc.

Add some const qualifiers.

storage/innobase/include/trx0undo.h

@@ -122,17 +122,6 @@ UNIV_INLINE
 page_t*
 trx_undo_page_get_s_latched(const page_id_t& page_id, mtr_t* mtr);
 
-/******************************************************************//**
-Returns the previous undo record on the page in the specified log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_prev_rec(
-/*=======================*/
-	trx_undo_rec_t*	rec,	/*!< in: undo log record */
-	ulint		page_no,/*!< in: undo log header page number */
-	ulint		offset);/*!< in: undo log header offset on page */
 /******************************************************************//**
 Returns the next undo log record on the page in the specified log, or
 NULL if none exists.
@@ -144,28 +133,6 @@ trx_undo_page_get_next_rec(
 	trx_undo_rec_t*	rec,	/*!< in: undo log record */
 	ulint		page_no,/*!< in: undo log header page number */
 	ulint		offset);/*!< in: undo log header offset on page */
-/******************************************************************//**
-Returns the last undo record on the page in the specified undo log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_last_rec(
-/*=======================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset);	/*!< in: undo log header offset on page */
-/******************************************************************//**
-Returns the first undo record on the page in the specified undo log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_first_rec(
-/*========================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset);/*!< in: undo log header offset on page */
 /***********************************************************************//**
 Gets the previous record in an undo log.
 @return undo log record, the page s-latched, NULL if none */

storage/innobase/include/trx0undo.ic

 /*****************************************************************************
 
 Copyright (c) 1996, 2013, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, MariaDB Corporation.
+Copyright (c) 2017, 2018, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -184,51 +184,19 @@ trx_undo_page_get_s_latched(const page_id_t& page_id, mtr_t* mtr)
 	return(buf_block_get_frame(block));
 }
 
-/******************************************************************//**
-Returns the start offset of the undo log records of the specified undo
-log on the page.
-@return start offset */
-UNIV_INLINE
-ulint
-trx_undo_page_get_start(
-/*====================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset)	/*!< in: undo log header offset on page */
-{
-	ulint	start;
-
-	if (page_no == page_get_page_no(undo_page)) {
-
-		start = mach_read_from_2(offset + undo_page
-					 + TRX_UNDO_LOG_START);
-	} else {
-		start = TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE;
-	}
-
-	return(start);
-}
-
-/******************************************************************//**
-Returns the end offset of the undo log records of the specified undo
-log on the page.
+/** Determine the end offset of undo log records of an undo log page.
+@param[in]	undo_page	undo log page
+@param[in]	page_no		undo log header page number
+@param[in]	offset		undo log header offset
 @return end offset */
-UNIV_INLINE
-ulint
-trx_undo_page_get_end(
-/*==================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset)	/*!< in: undo log header offset on page */
+inline
+uint16_t
+trx_undo_page_get_end(const page_t* undo_page, ulint page_no, ulint offset)
 {
-	trx_ulogf_t*	log_hdr;
-	ulint		end;
+	uint16_t end;
 
 	if (page_no == page_get_page_no(undo_page)) {
-
-		log_hdr = undo_page + offset;
-
-		end = mach_read_from_2(log_hdr + TRX_UNDO_NEXT_LOG);
+		end = mach_read_from_2(offset + TRX_UNDO_NEXT_LOG + undo_page);
 
 		if (end == 0) {
 			end = mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
@@ -242,33 +210,6 @@ trx_undo_page_get_end(
 	return(end);
 }
 
-/******************************************************************//**
-Returns the previous undo record on the page in the specified log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_prev_rec(
-/*=======================*/
-	trx_undo_rec_t*	rec,	/*!< in: undo log record */
-	ulint		page_no,/*!< in: undo log header page number */
-	ulint		offset)	/*!< in: undo log header offset on page */
-{
-	page_t*	undo_page;
-	ulint	start;
-
-	undo_page = (page_t*) ut_align_down(rec, UNIV_PAGE_SIZE);
-
-	start = trx_undo_page_get_start(undo_page, page_no, offset);
-
-	if (start + undo_page == rec) {
-
-		return(NULL);
-	}
-
-	return(undo_page + mach_read_from_2(rec - 2));
-}
-
 /******************************************************************//**
 Returns the next undo log record on the page in the specified log, or
 NULL if none exists.
@@ -298,55 +239,3 @@ trx_undo_page_get_next_rec(
 
 	return(undo_page + next);
 }
-
-/******************************************************************//**
-Returns the last undo record on the page in the specified undo log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_last_rec(
-/*=======================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset)	/*!< in: undo log header offset on page */
-{
-	ulint	start;
-	ulint	end;
-
-	start = trx_undo_page_get_start(undo_page, page_no, offset);
-	end = trx_undo_page_get_end(undo_page, page_no, offset);
-
-	if (start == end) {
-
-		return(NULL);
-	}
-
-	return(undo_page + mach_read_from_2(undo_page + end - 2));
-}
-
-/******************************************************************//**
-Returns the first undo record on the page in the specified undo log, or
-NULL if none exists.
-@return pointer to record, NULL if none */
-UNIV_INLINE
-trx_undo_rec_t*
-trx_undo_page_get_first_rec(
-/*========================*/
-	page_t*	undo_page,/*!< in: undo log page */
-	ulint	page_no,/*!< in: undo log header page number */
-	ulint	offset)	/*!< in: undo log header offset on page */
-{
-	ulint	start;
-	ulint	end;
-
-	start = trx_undo_page_get_start(undo_page, page_no, offset);
-	end = trx_undo_page_get_end(undo_page, page_no, offset);
-
-	if (start == end) {
-
-		return(NULL);
-	}
-
-	return(undo_page + start);
-}

storage/innobase/trx/trx0undo.cc

@@ -117,6 +117,53 @@ trx_undo_mem_create(
 	ulint		page_no,/*!< in: undo log header page number */
 	ulint		offset);/*!< in: undo log header byte offset on page */
 
+/** Determine the start offset of undo log records of an undo log page.
+@param[in]	undo_page	undo log page
+@param[in]	page_no		undo log header page number
+@param[in]	offset		undo log header offset
+@return start offset */
+static
+uint16_t
+trx_undo_page_get_start(const page_t* undo_page, ulint page_no, ulint offset)
+{
+	return page_no == page_get_page_no(undo_page)
+		? mach_read_from_2(offset + TRX_UNDO_LOG_START + undo_page)
+		: TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE;
+}
+
+/** Get the first undo log record on a page.
+@param[in]	page	undo log page
+@param[in]	page_no	undo log header page number
+@param[in]	offset	undo log header page offset
+@return	pointer to first record
+@retval	NULL	if none exists */
+static
+trx_undo_rec_t*
+trx_undo_page_get_first_rec(page_t* page, ulint page_no, ulint offset)
+{
+	ulint start = trx_undo_page_get_start(page, page_no, offset);
+	return start == trx_undo_page_get_end(page, page_no, offset)
+		? NULL
+		: page + start;
+}
+
+/** Get the last undo log record on a page.
+@param[in]	page	undo log page
+@param[in]	page_no	undo log header page number
+@param[in]	offset	undo log header page offset
+@return	pointer to last record
+@retval	NULL	if none exists */
+static
+trx_undo_rec_t*
+trx_undo_page_get_last_rec(page_t* page, ulint page_no, ulint offset)
+{
+	ulint end = trx_undo_page_get_end(page, page_no, offset);
+
+	return trx_undo_page_get_start(page, page_no, offset) == end
+		? NULL
+		: page + mach_read_from_2(page + end - 2);
+}
+
 /***********************************************************************//**
 Gets the previous record in an undo log from the previous page.
 @return undo log record, the page s-latched, NULL if none */
@@ -159,6 +206,31 @@ trx_undo_get_prev_rec_from_prev_page(
 	return(trx_undo_page_get_last_rec(prev_page, page_no, offset));
 }
 
+/** Get the previous undo log record.
+@param[in]	rec	undo log record
+@param[in]	page_no	undo log header page number
+@param[in]	offset	undo log header page offset
+@return	pointer to record
+@retval	NULL if none */
+static
+trx_undo_rec_t*
+trx_undo_page_get_prev_rec(trx_undo_rec_t* rec, ulint page_no, ulint offset)
+{
+	page_t*	undo_page;
+	ulint	start;
+
+	undo_page = (page_t*) ut_align_down(rec, UNIV_PAGE_SIZE);
+
+	start = trx_undo_page_get_start(undo_page, page_no, offset);
+
+	if (start + undo_page == rec) {
+
+		return(NULL);
+	}
+
+	return(undo_page + mach_read_from_2(rec - 2));
+}
+
 /***********************************************************************//**
 Gets the previous record in an undo log.
 @return undo log record, the page s-latched, NULL if none */