Fix pg_rewind debug output to print the source timeline history

getTimelineHistory() is called twice, to read the source and the
target timeline history files. However, the loop to print the file
with the --debug option used the wrong variable when dealing with the
source. As a result, the source's history was always printed as empty.

Spotted while debugging bug #18575, but this does not fix that bug,
just the debugging output. Backpatch to all supported versions.

Discussion: https://www.postgresql.org/message-id/092dd515-b7b4-4fd0-8407-ceca2f02f6ec@iki.fi

diff --git a/src/bin/pg_rewind/pg_rewind.c b/src/bin/pg_rewind/pg_rewind.c
index 2a18f675c84ba3a91039fd551be92182781bbf38..5b1b3e62ccee144a619e03298591f638315b85e2 100644 (file)
--- a/src/bin/pg_rewind/pg_rewind.c
+++ b/src/bin/pg_rewind/pg_rewind.c
@@ -578,6 +578,7 @@ getTimelineHistory(ControlFileData *controlFile, int *nentries)
                pg_free(histfile);
        }
 
+       /* In debugging mode, print what we read */
        if (debug)
        {
                int                     i;
@@ -589,10 +590,7 @@ getTimelineHistory(ControlFileData *controlFile, int *nentries)
                else
                        Assert(false);
 
-               /*
-                * Print the target timeline history.
-                */
-               for (i = 0; i < targetNentries; i++)
+               for (i = 0; i < *nentries; i++)
                {
                        TimeLineHistoryEntry *entry;