From 0f82db941b9a9dddf6837a8bf4a086add29ea71b Mon Sep 17 00:00:00 2001
From: Leo Yuriev <leo@yuriev.ru>
Date: Thu, 4 Oct 2018 16:00:27 +0300
Subject: [PATCH] mdbx: add error-logging to mdbx_page_get().

Change-Id: I6a1a95ec6fc73aa7bf28875a89b1dd6c02ef5164
---
 src/mdbx.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/mdbx.c b/src/mdbx.c
index 1b2378ac..883b7a31 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -6927,13 +6927,20 @@ mapped:
   p = pgno2page(env, pgno);
 
 done:
-  if (unlikely(p->mp_pgno != pgno))
+  if (unlikely(p->mp_pgno != pgno)) {
+    mdbx_error("mismatch pgno %" PRIaPGNO " (actual) != %" PRIaPGNO
+               " (expected)",
+               p->mp_pgno, pgno);
     return MDBX_CORRUPTED;
+  }
 
   if (unlikely(p->mp_upper < p->mp_lower ||
                PAGEHDRSZ + p->mp_upper > env->me_psize) &&
-      !IS_OVERFLOW(p))
+      !IS_OVERFLOW(p)) {
+    mdbx_error("invalid page lower(%u)/upper(%u), pg-limit %u", p->mp_lower,
+               p->mp_upper, env->me_psize - PAGEHDRSZ);
     return MDBX_CORRUPTED;
+  }
   /* TODO: more checks here, including p->mp_validator */
 
   *ret = p;