improve error message on corrup schema file

ndb/src/kernel/blocks/dbdict/Dbdict.cpp

@@ -79,6 +79,9 @@
 #include <NdbSleep.h>
 #include <signaldata/ApiBroadcast.hpp>
 
+#include <EventLogger.hpp>
+extern EventLogger g_eventLogger;
+
 #define ZNOT_FOUND 626
 #define ZALREADYEXIST 630
 
@@ -1070,26 +1073,34 @@ void Dbdict::readSchemaConf(Signal* signal,
   for (Uint32 n = 0; n < xsf->noOfPages; n++) {
     SchemaFile * sf = &xsf->schemaPage[n];
     bool ok = false;
+    const char *reason;
     if (memcmp(sf->Magic, NDB_SF_MAGIC, sizeof(sf->Magic)) != 0)
-    { jam(); }
+    { jam(); reason = "magic code"; }
     else if (sf->FileSize == 0)
-    { jam(); }
+    { jam(); reason = "file size == 0"; }
     else if (sf->FileSize % NDB_SF_PAGE_SIZE != 0)
-    { jam(); }
+    { jam(); reason = "invalid size multiple"; }
     else if (sf->FileSize != sf0->FileSize)
-    { jam(); }
+    { jam(); reason = "invalid size"; }
     else if (sf->PageNumber != n)
-    { jam(); }
+    { jam(); reason = "invalid page number"; }
     else if (computeChecksum((Uint32*)sf, NDB_SF_PAGE_SIZE_IN_WORDS) != 0)
-    { jam(); }
-    else if (crashInd)
-    { jam(); }
+    { jam(); reason = "invalid checksum"; }
     else
       ok = true;
-    ndbrequireErr(ok, NDBD_EXIT_SR_SCHEMAFILE);
-    if (! ok) {
+
+    if (!ok)
+    {
+      char reason_msg[128];
+      snprintf(reason_msg, sizeof(reason_msg),
+               "schema file corrupt, page %u (%s, "
+               "sz=%u sz0=%u pn=%u)",
+               n, reason, sf->FileSize, sf0->FileSize, sf->PageNumber);
+      if (crashInd)
+        progError(__LINE__, NDBD_EXIT_SR_SCHEMAFILE, reason_msg);
       jam();
       ndbrequire(fsPtr.p->fsState == FsConnectRecord::READ_SCHEMA1);
+      infoEvent("primary %s, trying backup", reason_msg);
       readSchemaRef(signal, fsPtr);
       return;
     }