diff --git a/src/sqlite3.c b/src/sqlite3.c
index 946815f13ec88233ffd608e68a1000284d9b517e..f77f7739053a0758d1b696c3f581cfb6a0ae5785 100644
--- a/src/sqlite3.c
+++ b/src/sqlite3.c
@@ -43317,6 +43317,7 @@ shmpage_out:
     *pp = 0;
   }
   if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
+  sqlite3_log(rc, "linzhb: unixShmMap, fileName[%s], errno[%d]", pShmNode->zFilename, errno);
   sqlite3_mutex_leave(pShmNode->pShmMutex);
   return rc;
 }
@@ -50999,6 +51000,7 @@ shmpage_out:
     *pp = 0;
   }
   if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
+  sqlite3_log(rc, "linzhb: unixShmMap, fileName[%s], errno[%d]", pShmNode->zFilename, errno);
   sqlite3_mutex_leave(pShmNode->mutex);
   return rc;
 }
@@ -53243,6 +53245,7 @@ static int memdbLock(sqlite3_file *pFile, int eLock){
 
   if( eLock>SQLITE_LOCK_SHARED && (p->mFlags & SQLITE_DESERIALIZE_READONLY) ){
     rc = SQLITE_READONLY;
+    sqlite3_log(rc, "linzhb: memdbLock, eLock[%d], mFlags[%d], errno[%d]", eLock, p->mFlags, errno);
   }else{
     switch( eLock ){
       case SQLITE_LOCK_SHARED: {
@@ -62029,6 +62032,7 @@ SQLITE_PRIVATE int sqlite3PagerOpen(
     assert( !memDb );
     pPager->memVfs = memJM = (fout&SQLITE_OPEN_MEMORY)!=0;
     readOnly = (fout&SQLITE_OPEN_READONLY)!=0;
+    sqlite3_log(rc, "linzhb: sqlite3PagerOpen1, readOnly[%d], fout[%d], vfsFlags[%d], errno[%d]", readOnly, fout, vfsFlags, errno);
 
     /* If the file was successfully opened for read/write access,
     ** choose a default page size in case we have to create the
@@ -62068,6 +62072,7 @@ SQLITE_PRIVATE int sqlite3PagerOpen(
       if( (iDc & SQLITE_IOCAP_IMMUTABLE)!=0
        || sqlite3_uri_boolean(pPager->zFilename, "immutable", 0) ){
           vfsFlags |= SQLITE_OPEN_READONLY;
+          sqlite3_log(rc, "linzhb: sqlite3PagerOpen2, readOnly[%d], vfsFlags[%d], errno[%d]", readOnly, vfsFlags, errno);
           goto act_like_temp_file;
       }
     }
@@ -62139,6 +62144,7 @@ act_like_temp_file:
   pPager->readOnly = (u8)readOnly;
   assert( useJournal || pPager->tempFile );
   sqlite3PagerSetFlags(pPager, (SQLITE_DEFAULT_SYNCHRONOUS+1)|PAGER_CACHESPILL);
+  sqlite3_log(rc, "linzhb: sqlite3PagerOpen4, readOnly[%d], vfsFlags[%d], errno[%d]", readOnly, vfsFlags, errno);
   /* pPager->pFirst = 0; */
   /* pPager->pFirstSynced = 0; */
   /* pPager->pLast = 0; */
@@ -65693,6 +65699,7 @@ static SQLITE_NOINLINE int walIndexPageRealloc(
       if( iPage>0 && sqlite3FaultSim(600) ) rc = SQLITE_NOMEM;
     }else if( (rc&0xff)==SQLITE_READONLY ){
       pWal->readOnly |= WAL_SHM_RDONLY;
+      sqlite3_log(rc, "linzhb: walIndexPageRealloc, readOnly[%d], errno[%d]", pWal->readOnly, errno);
       if( rc==SQLITE_READONLY ){
         rc = SQLITE_OK;
       }
@@ -67716,6 +67723,7 @@ static int walBeginShmUnreliable(Wal *pWal, int *pChanged){
   rc = sqlite3OsShmMap(pWal->pDbFd, 0, WALINDEX_PGSZ, 0, &pDummy);
   assert( rc!=SQLITE_OK ); /* SQLITE_OK not possible for read-only connection */
   if( rc!=SQLITE_READONLY_CANTINIT ){
+    sqlite3_log(rc, "linzhb: walBeginShmUnreliable, fileName[%s], errno[%d]", pWal->zWalName, errno);
     rc = (rc==SQLITE_READONLY ? WAL_RETRY : rc);
     goto begin_unreliable_shm_out;
   }
@@ -68583,6 +68591,7 @@ SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal){
   assert( pWal->writeLock==0 && pWal->iReCksum==0 );
 
   if( pWal->readOnly ){
+    sqlite3_log(SQLITE_READONLY, "linzhb: sqlite3WalBeginWriteTransaction, fileName[%s], errno[%d]", pWal->zWalName, errno);
     return SQLITE_READONLY;
   }
 
@@ -69186,6 +69195,7 @@ SQLITE_PRIVATE int sqlite3WalCheckpoint(
   ** in the SQLITE_CHECKPOINT_PASSIVE mode. */
   assert( eMode!=SQLITE_CHECKPOINT_PASSIVE || xBusy==0 );
 
+  if( pWal->readOnly ) sqlite3_log(SQLITE_READONLY, "linzhb: sqlite3WalCheckpoint, fileName[%s], errno[%d]", pWal->zWalName, errno);
   if( pWal->readOnly ) return SQLITE_READONLY;
   WALTRACE(("WAL%p: checkpoint begins\n", pWal));
 
@@ -73228,7 +73238,10 @@ SQLITE_PRIVATE int sqlite3BtreeOpen(
 
     pBt->pCursor = 0;
     pBt->pPage1 = 0;
-    if( sqlite3PagerIsreadonly(pBt->pPager) ) pBt->btsFlags |= BTS_READ_ONLY;
+        if( sqlite3PagerIsreadonly(pBt->pPager) ) {
+            pBt->btsFlags |= BTS_READ_ONLY;
+            sqlite3_log(rc, "linzhb: sqlite3BtreeOpen, pBt->btsFlags[%d], errno[%d]", pBt->btsFlags, errno);
+          }
 #if defined(SQLITE_SECURE_DELETE)
     pBt->btsFlags |= BTS_SECURE_DELETE;
 #elif defined(SQLITE_FAST_SECURE_DELETE)
@@ -73613,6 +73626,7 @@ SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int pageSize, int nReserve,
   if( nReserve<x ) nReserve = x;
   if( pBt->btsFlags & BTS_PAGESIZE_FIXED ){
     sqlite3BtreeLeave(p);
+    sqlite3_log(rc, "linzhb: sqlite3BtreeSetPageSize, pBt->btsFlags[%d], errno[%d]", pBt->btsFlags, errno);
     return SQLITE_READONLY;
   }
   assert( nReserve>=0 && nReserve<=255 );
@@ -73729,6 +73743,7 @@ SQLITE_PRIVATE int sqlite3BtreeSecureDelete(Btree *p, int newFlag){
 */
 SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *p, int autoVacuum){
 #ifdef SQLITE_OMIT_AUTOVACUUM
+sqlite3_log(SQLITE_READONLY, "linzhb: sqlite3BtreeSetAutoVacuum, autoVacuum[%d], errno[%d]", autoVacuum, errno);
   return SQLITE_READONLY;
 #else
   BtShared *pBt = p->pBt;
@@ -73738,6 +73753,7 @@ SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *p, int autoVacuum){
   sqlite3BtreeEnter(p);
   if( (pBt->btsFlags & BTS_PAGESIZE_FIXED)!=0 && (av ?1:0)!=pBt->autoVacuum ){
     rc = SQLITE_READONLY;
+    sqlite3_log(rc, "linzhb: sqlite3BtreeSetAutoVacuum, pBt->btsFlags[%d], pBt->autoVacuum[%d], errno[%d]", pBt->btsFlags, pBt->autoVacuum, errno);
   }else{
     pBt->autoVacuum = av ?1:0;
     pBt->incrVacuum = av==2 ?1:0;
@@ -73798,6 +73814,33 @@ static void setDefaultSyncFlag(BtShared *pBt, u8 safety_level){
 static int newDatabase(BtShared*);
 
 
+void DumpBuf(const uint8_t *ptr, uint32_t size)
+{
+  if (ptr == NULL){
+    return;
+  }
+  uint32_t logSize = size*2 + 1;
+  char *log = malloc(logSize);
+  if (log == NULL){
+    sqlite3_log(SQLITE_CORRUPT, "alloc mem unsucc at dump buf");
+    return;
+  }
+  uint32_t idx = 0;
+  uint32_t i = 0;
+  while (idx < size){
+    for (i = 0; i < 100 && idx < size; i++){
+      (void)sprintf(log + i * 2, "%02x", *(ptr + idx));
+      idx++;
+    }
+    log[i * 2] = '\0';
+    sqlite3_log(SQLITE_CORRUPT, "%s", log);
+  }
+  free(log);
+}
+
+
+
+
 /*
 ** Get a reference to pPage1 of the database file.  This will
 ** also acquire a readlock on that file.
@@ -73853,6 +73896,8 @@ static int lockBtree(BtShared *pBt){
 #else
     if( page1[18]>2 ){
       pBt->btsFlags |= BTS_READ_ONLY;
+      sqlite3_log(rc, "linzhb: lockBtree, pBt->btsFlags[%d], errno[%d]", pBt->btsFlags, errno);
+      DumpBuf((const uint8_t *)pPage1->aData, 100);
     }
     if( page1[19]>2 ){
       goto page1_init_failed;
@@ -74153,6 +74198,7 @@ static SQLITE_NOINLINE int btreeBeginTrans(
   /* Write transactions are not possible on a read-only database */
   if( (pBt->btsFlags & BTS_READ_ONLY)!=0 && wrflag ){
     rc = SQLITE_READONLY;
+    sqlite3_log(rc, "linzhb: btreeBeginTrans1, pBt->btsFlags[%d], errno[%d]", pBt->btsFlags, errno);
     goto trans_begun;
   }
 
@@ -74217,6 +74263,7 @@ static SQLITE_NOINLINE int btreeBeginTrans(
     if( rc==SQLITE_OK && wrflag ){
       if( (pBt->btsFlags & BTS_READ_ONLY)!=0 ){
         rc = SQLITE_READONLY;
+        sqlite3_log(rc, "linzhb: btreeBeginTrans2, pBt->btsFlags[%d], errno[%d]", pBt->btsFlags, errno);
       }else{
         rc = sqlite3PagerBegin(pPager, wrflag>1, sqlite3TempInMemory(p->db));
         if( rc==SQLITE_OK ){
@@ -81902,6 +81949,7 @@ SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void
   **   (e) the cursor points at a valid row of an intKey table.
   */
   if( (pCsr->curFlags & BTCF_WriteFlag)==0 ){
+    sqlite3_log(SQLITE_READONLY, "linzhb: sqlite3BtreePutData, pCsr->curFlags[%d], errno[%d]", pCsr->curFlags, errno);
     return SQLITE_READONLY;
   }
   assert( (pCsr->pBt->btsFlags & BTS_READ_ONLY)==0
@@ -82392,6 +82440,7 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
      && pgszSrc!=pgszDest
     ){
       rc = SQLITE_READONLY;
+      sqlite3_log(rc, "linzhb: sqlite3_backup_step, pgszSrc[%d], pgszDest[%d], errno[%d]", pgszSrc, pgszDest, errno);
     }
 
     /* Now that there is a read-lock on the source database, query the
@@ -97139,6 +97188,7 @@ case OP_Transaction: {
     if( db->flags & SQLITE_QueryOnly ){
       /* Writes prohibited by the "PRAGMA query_only=TRUE" statement */
       rc = SQLITE_READONLY;
+      sqlite3_log(rc, "linzhb: OP_Transaction, db->flags[%d], errno[%d]", db->flags, errno);
     }else{
       /* Writes prohibited due to a prior SQLITE_CORRUPT in the current
       ** transaction */