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 1ff8da1676481fa39737a3c6e305f35e822f4e74..11b1ef3bfed522934335bc4796d58edc2d69fa5a 100644 (file)
--- a/src/bin/pg_rewind/pg_rewind.c
+++ b/src/bin/pg_rewind/pg_rewind.c
@@ -837,6 +837,7 @@ getTimelineHistory(ControlFileData *controlFile, int *nentries)
        pg_free(histfile);
    }
 
+   /* In debugging mode, print what we read */
    if (debug)
    {
        int         i;
@@ -848,10 +849,7 @@ 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;