Error message editing: finish up undone task of reporting the problem

xid when we fail to access pg_clog.

diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index 85e20e0e5b3915ef168e419f530e7b4bc047b9ae..31d668b608cc4340104c6032d7fe7f8584f87564 100644 (file)
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -1,19 +1,12 @@
 /*-------------------------------------------------------------------------
  *
  * slru.c
- *     Simple LRU
+ *     Simple LRU buffering for transaction status logfiles
  *
- * This module replaces the old "pg_log" access code, which treated pg_log
- * essentially like a relation, in that it went through the regular buffer
- * manager.  The problem with that was that there wasn't any good way to
- * recycle storage space for transactions so old that they'll never be
- * looked up again.  Now we use specialized access code so that the commit
- * log can be broken into relatively small, independent segments.
- *
- * Portions Copyright (c) 2003, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Header: /cvsroot/pgsql/src/backend/access/transam/slru.c,v 1.1 2003/06/11 22:37:45 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/transam/slru.c,v 1.2 2003/07/19 21:37:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -363,7 +356,7 @@ SimpleLruReadPage(SlruCtl ctl, int pageno, TransactionId xid, bool forwrite)
 
        LWLockRelease(ctl->locks->BufferLocks[slotno]);
 
-       /* Now it's okay to elog if we failed */
+       /* Now it's okay to ereport if we failed */
        if (!ok)
            SlruReportIOError(ctl, pageno, xid);
 
@@ -449,7 +442,7 @@ SimpleLruWritePage(SlruCtl ctl, int slotno)
 
    LWLockRelease(ctl->locks->BufferLocks[slotno]);
 
-   /* Now it's okay to elog if we failed */
+   /* Now it's okay to ereport if we failed */
    if (!ok)
        SlruReportIOError(ctl, pageno, InvalidTransactionId);
 }
@@ -457,7 +450,7 @@ SimpleLruWritePage(SlruCtl ctl, int slotno)
 /*
  * Physical read of a (previously existing) page into a buffer slot
  *
- * On failure, we cannot just elog(ERROR) since caller has put state in
+ * On failure, we cannot just ereport(ERROR) since caller has put state in
  * shared memory that must be undone.  So, we return FALSE and save enough
  * info in static variables to let SlruReportIOError make the report.
  *
@@ -493,7 +486,9 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno)
            return false;
        }
 
-       elog(LOG, "file %s doesn't exist, reading as zeroes", path);
+       ereport(LOG,
+               (errmsg("file \"%s\" doesn't exist, reading as zeroes",
+                       path)));
        MemSet(shared->page_buffer[slotno], 0, BLCKSZ);
        return true;
    }
@@ -520,7 +515,7 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno)
 /*
  * Physical write of a page from a buffer slot
  *
- * On failure, we cannot just elog(ERROR) since caller has put state in
+ * On failure, we cannot just ereport(ERROR) since caller has put state in
  * shared memory that must be undone.  So, we return FALSE and save enough
  * info in static variables to let SlruReportIOError make the report.
  *
@@ -606,33 +601,49 @@ SlruReportIOError(SlruCtl ctl, int pageno, TransactionId xid)
    int         offset = rpageno * BLCKSZ;
    char        path[MAXPGPATH];
 
-   /* XXX TODO: provide xid as context in error messages */
-
    SlruFileName(ctl, path, segno);
    errno = slru_errno;
    switch (slru_errcause)
    {
        case SLRU_OPEN_FAILED:
-           elog(ERROR, "open of %s failed: %m", path);
+           ereport(ERROR,
+                   (errcode_for_file_access(),
+                    errmsg("could not access status of transaction %u", xid),
+                    errdetail("open of file \"%s\" failed: %m",
+                              path)));
            break;
        case SLRU_CREATE_FAILED:
-           elog(ERROR, "creation of file %s failed: %m", path);
+           ereport(ERROR,
+                   (errcode_for_file_access(),
+                    errmsg("could not access status of transaction %u", xid),
+                    errdetail("creation of file \"%s\" failed: %m",
+                              path)));
            break;
        case SLRU_SEEK_FAILED:
-           elog(ERROR, "lseek of file %s, offset %u failed: %m",
-                path, offset);
+           ereport(ERROR,
+                   (errcode_for_file_access(),
+                    errmsg("could not access status of transaction %u", xid),
+                    errdetail("lseek of file \"%s\", offset %u failed: %m",
+                              path, offset)));
            break;
        case SLRU_READ_FAILED:
-           elog(ERROR, "read of file %s, offset %u failed: %m",
-                path, offset);
+           ereport(ERROR,
+                   (errcode_for_file_access(),
+                    errmsg("could not access status of transaction %u", xid),
+                    errdetail("read of file \"%s\", offset %u failed: %m",
+                              path, offset)));
            break;
        case SLRU_WRITE_FAILED:
-           elog(ERROR, "write of file %s, offset %u failed: %m",
-                path, offset);
+           ereport(ERROR,
+                   (errcode_for_file_access(),
+                    errmsg("could not access status of transaction %u", xid),
+                    errdetail("write of file \"%s\", offset %u failed: %m",
+                              path, offset)));
            break;
        default:
            /* can't get here, we trust */
-           elog(ERROR, "unknown SimpleLru I/O error");
+           elog(ERROR, "unrecognized SimpleLru error cause: %d",
+                (int) slru_errcause);
            break;
    }
 }
@@ -799,7 +810,9 @@ restart:;
    if (ctl->PagePrecedes(shared->latest_page_number, cutoffPage))
    {
        LWLockRelease(ctl->locks->ControlLock);
-       elog(LOG, "unable to truncate %s: apparent wraparound", ctl->Dir);
+       ereport(LOG,
+               (errmsg("unable to truncate \"%s\": apparent wraparound",
+                       ctl->Dir)));
        return;
    }
 
@@ -855,7 +868,9 @@ SlruScanDirectory(SlruCtl ctl, int cutoffPage, bool doDeletions)
 
    cldir = opendir(ctl->Dir);
    if (cldir == NULL)
-       elog(ERROR, "could not open directory (%s): %m", ctl->Dir);
+       ereport(ERROR,
+               (errcode_for_file_access(),
+                errmsg("could not open directory \"%s\": %m", ctl->Dir)));
 
    errno = 0;
    while ((clde = readdir(cldir)) != NULL)
@@ -870,7 +885,9 @@ SlruScanDirectory(SlruCtl ctl, int cutoffPage, bool doDeletions)
                found = true;
                if (doDeletions)
                {
-                   elog(LOG, "removing file %s/%s", ctl->Dir, clde->d_name);
+                   ereport(LOG,
+                           (errmsg("removing file \"%s/%s\"",
+                                   ctl->Dir, clde->d_name)));
                    snprintf(path, MAXPGPATH, "%s/%s", ctl->Dir, clde->d_name);
                    unlink(path);
                }
@@ -879,7 +896,9 @@ SlruScanDirectory(SlruCtl ctl, int cutoffPage, bool doDeletions)
        errno = 0;
    }
    if (errno)
-       elog(ERROR, "could not read directory (%s): %m", ctl->Dir);
+       ereport(ERROR,
+               (errcode_for_file_access(),
+                errmsg("could not read directory \"%s\": %m", ctl->Dir)));
    closedir(cldir);
 
    return found;