diff options
Diffstat (limited to 'src/include/access/xlogreader.h')
| -rw-r--r-- | src/include/access/xlogreader.h | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h index 735b1bd2fd6..1bbee386e8d 100644 --- a/src/include/access/xlogreader.h +++ b/src/include/access/xlogreader.h @@ -31,6 +31,22 @@ #include "access/xlogrecord.h" +/* WALOpenSegment represents a WAL segment being read. */ +typedef struct WALOpenSegment +{ + int ws_file; /* segment file descriptor */ + XLogSegNo ws_segno; /* segment number */ + uint32 ws_off; /* offset in the segment */ + TimeLineID ws_tli; /* timeline ID of the currently open file */ +} WALOpenSegment; + +/* WALSegmentContext carries context information about WAL segments to read */ +typedef struct WALSegmentContext +{ + char ws_dir[MAXPGPATH]; + int ws_segsize; +} WALSegmentContext; + typedef struct XLogReaderState XLogReaderState; /* Function type definition for the read_page callback */ @@ -38,8 +54,7 @@ typedef int (*XLogPageReadCB) (XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *readBuf, - TimeLineID *pageTLI); + char *readBuf); typedef struct { @@ -78,11 +93,6 @@ struct XLogReaderState */ /* - * Segment size of the to-be-parsed data (mandatory). - */ - int wal_segment_size; - - /* * Data input callback (mandatory). * * This callback shall read at least reqLen valid bytes of the xlog page @@ -99,9 +109,8 @@ struct XLogReaderState * actual WAL record it's interested in. In that case, targetRecPtr can * be used to determine which timeline to read the page from. * - * The callback shall set *pageTLI to the TLI of the file the page was - * read from. It is currently used only for error reporting purposes, to - * reconstruct the name of the WAL file where an error occurred. + * The callback shall set ->seg.ws_tli to the TLI of the file the page was + * read from. */ XLogPageReadCB read_page; @@ -156,10 +165,9 @@ struct XLogReaderState char *readBuf; uint32 readLen; - /* last read segment, segment offset, TLI for data currently in readBuf */ - XLogSegNo readSegNo; - uint32 readOff; - TimeLineID readPageTLI; + /* last read XLOG position for data currently in readBuf */ + WALSegmentContext segcxt; + WALOpenSegment seg; /* * beginning of prior page read, and its TLI. Doesn't necessarily @@ -202,12 +210,17 @@ struct XLogReaderState /* Get a new XLogReader */ extern XLogReaderState *XLogReaderAllocate(int wal_segment_size, + const char *waldir, XLogPageReadCB pagereadfunc, void *private_data); /* Free an XLogReader */ extern void XLogReaderFree(XLogReaderState *state); +/* Initialize supporting structures */ +extern void WALOpenSegmentInit(WALOpenSegment *seg, WALSegmentContext *segcxt, + int segsize, const char *waldir); + /* Read the next XLog record. Returns NULL on end-of-WAL or failure */ extern struct XLogRecord *XLogReadRecord(XLogReaderState *state, XLogRecPtr recptr, char **errormsg); |