Fix case of pg_dump -Fc to an unseekable file (such as a pipe).

This was accidentally broken in commits cfa1b4a711/5e8e794e3b.
It saves a line or so to call ftello unconditionally in _CloseArchive,
but we have to expect that it might fail if we're not in hasSeek mode.
Per report from Bernd Helmle.

In passing, improve _getFilePos to print an appropriate message if
ftello fails unexpectedly, rather than just a vague complaint about
"ftell mismatch".

diff --git a/src/bin/pg_dump/pg_backup_custom.c b/src/bin/pg_dump/pg_backup_custom.c
index 72bdc3928b2b401e714d9a405982dab605787c74..de4f023fa748b37306753f83f6d07c4d164c89e3 100644 (file)
--- a/src/bin/pg_dump/pg_backup_custom.c
+++ b/src/bin/pg_dump/pg_backup_custom.c
@@ -707,8 +707,9 @@ _CloseArchive(ArchiveHandle *AH)
    if (AH->mode == archModeWrite)
    {
        WriteHead(AH);
+       /* Remember TOC's seek position for use below */
        tpos = ftello(AH->FH);
-       if (tpos < 0)
+       if (tpos < 0 && ctx->hasSeek)
            exit_horribly(modulename, "could not determine seek position in archive file: %s\n",
                          strerror(errno));
        WriteToc(AH);
@@ -899,17 +900,20 @@ _getFilePos(ArchiveHandle *AH, lclContext *ctx)
 
    if (ctx->hasSeek)
    {
+       /*
+        * Prior to 1.7 (pg7.3) we relied on the internally maintained
+        * pointer.  Now we rely on ftello() always, unless the file has been
+        * found to not support it.  For debugging purposes, print a warning
+        * if the internal pointer disagrees, so that we're more likely to
+        * notice if something's broken about the internal position tracking.
+        */
        pos = ftello(AH->FH);
+       if (pos < 0)
+           exit_horribly(modulename, "could not determine seek position in archive file: %s\n",
+                         strerror(errno));
+
        if (pos != ctx->filePos)
-       {
            write_msg(modulename, "WARNING: ftell mismatch with expected position -- ftell used\n");
-
-           /*
-            * Prior to 1.7 (pg7.3) we relied on the internally maintained
-            * pointer. Now we rely on ftello() always, unless the file has
-            * been found to not support it.
-            */
-       }
    }
    else
        pos = ctx->filePos;