}
/*
- * Read the XLOG page containing RecPtr into readBuf (if not read already).
- * Returns number of bytes read, if the page is read successfully, or
- * XLREAD_FAIL in case of errors. When errors occur, they are ereport'ed, but
- * only if they have not been previously reported.
+ * Read the XLOG page containing targetPagePtr into readBuf (if not read
+ * already). Returns number of bytes read, if the page is read successfully,
+ * or XLREAD_FAIL in case of errors. When errors occur, they are ereport'ed,
+ * but only if they have not been previously reported.
+ *
+ * See XLogReaderRoutine.page_read for more details.
*
* While prefetching, xlogreader->nonblocking may be set. In that case,
* returns XLREAD_WOULDBLOCK if we'd otherwise have to wait for more WAL.
* This is responsible for restoring files from archive as needed, as well
* as for waiting for the requested WAL record to arrive in standby mode.
*
- * 'emode' specifies the log level used for reporting "file not found" or
- * "end of WAL" situations in archive recovery, or in standby mode when
- * promotion is triggered. If set to WARNING or below, XLogPageRead() returns
- * XLREAD_FAIL in those situations, on higher log levels the ereport() won't
- * return.
+ * xlogreader->private_data->emode specifies the log level used for reporting
+ * "file not found" or "end of WAL" situations in archive recovery, or in
+ * standby mode when promotion is triggered. If set to WARNING or below,
+ * XLogPageRead() returns XLREAD_FAIL in those situations, on higher log
+ * levels the ereport() won't return.
*
* In standby mode, if after a successful return of XLogPageRead() the
* caller finds the record it's interested in to be broken, it should