Add the SQLITE_ENABLE_API_ARMOR compile-time option. This is a work in

progress and is not yet completely functional.

FossilOrigin-Name: c297a84bc678f81ffc0aa9139ab73f0ca87c1971

18 files changed, 324 insertions, 22 deletions

diff --git a/src/auth.c b/src/auth.c
index 1680c9a7c..9768fc2fc 100644
--- a/src/auth.c
+++ b/src/auth.c
@@ -72,6 +72,9 @@ int sqlite3_set_authorizer(
   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
   void *pArg
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   db->xAuth = (sqlite3_xauth)xAuth;
   db->pAuthArg = pArg;
diff --git a/src/backup.c b/src/backup.c
index 92c6334bd..da4303e5f 100644
--- a/src/backup.c
+++ b/src/backup.c
@@ -138,6 +138,13 @@ sqlite3_backup *sqlite3_backup_init(
 ){
   sqlite3_backup *p;                    /* Value to return */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(pSrcDb)||!sqlite3SafetyCheckOk(pDestDb) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
+
   /* Lock the source database handle. The destination database
   ** handle is not locked in this routine, but it is locked in
   ** sqlite3_backup_step(). The user is required to ensure that no
@@ -334,6 +341,9 @@ int sqlite3_backup_step(sqlite3_backup *p, int nPage){
   int pgszSrc = 0;    /* Source page size */
   int pgszDest = 0;   /* Destination page size */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( p==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(p->pSrcDb->mutex);
   sqlite3BtreeEnter(p->pSrc);
   if( p->pDestDb ){
@@ -623,6 +633,12 @@ int sqlite3_backup_finish(sqlite3_backup *p){
 ** call to sqlite3_backup_step().
 */
 int sqlite3_backup_remaining(sqlite3_backup *p){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( p==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return p->nRemaining;
 }
 
@@ -631,6 +647,12 @@ int sqlite3_backup_remaining(sqlite3_backup *p){
 ** recent call to sqlite3_backup_step().
 */
 int sqlite3_backup_pagecount(sqlite3_backup *p){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( p==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return p->nPagecount;
 }
 
diff --git a/src/build.c b/src/build.c
index b897494db..0b4affc66 100644
--- a/src/build.c
+++ b/src/build.c
@@ -307,7 +307,11 @@ int sqlite3UserAuthTable(const char *zTable){
 Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
   Table *p = 0;
   int i;
-  assert( zName!=0 );
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return 0;
+#endif
+
   /* All mutexes are required for schema access.  Make sure we hold them. */
   assert( zDatabase!=0 || sqlite3BtreeHoldsAllMutexes(db) );
 #if SQLITE_USER_AUTHENTICATION
diff --git a/src/complete.c b/src/complete.c
index 6ab6f4a04..c439cfe18 100644
--- a/src/complete.c
+++ b/src/complete.c
@@ -105,6 +105,13 @@ int sqlite3_complete(const char *zSql){
   u8 state = 0;   /* Current state, using numbers defined in header comment */
   u8 token;       /* Value of the next token */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( zSql==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
+
 #ifndef SQLITE_OMIT_TRIGGER
   /* A complex statement machine used to detect the end of a CREATE TRIGGER
   ** statement.  This is the normal case.
diff --git a/src/ctime.c b/src/ctime.c
index 82a2f3520..36d0c266e 100644
--- a/src/ctime.c
+++ b/src/ctime.c
@@ -63,6 +63,9 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_DISABLE_LFS
   "DISABLE_LFS",
 #endif
+#ifdef SQLITE_ENABLE_API_ARMOR
+  "ENABLE_API_ARMOR",
+#endif
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
   "ENABLE_ATOMIC_WRITE",
 #endif
@@ -388,6 +391,13 @@ static const char * const azCompileOpt[] = {
 */
 int sqlite3_compileoption_used(const char *zOptName){
   int i, n;
+
+#ifdef SQLITE_ENABLE_API_ARMORE
+  if( zOptName==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   if( sqlite3StrNICmp(zOptName, "SQLITE_", 7)==0 ) zOptName += 7;
   n = sqlite3Strlen30(zOptName);
 
diff --git a/src/main.c b/src/main.c
index e6cb4cd3d..530869879 100644
--- a/src/main.c
+++ b/src/main.c
@@ -598,6 +598,12 @@ static int setupLookaside(sqlite3 *db, void *pBuf, int sz, int cnt){
 ** Return the mutex associated with a database connection.
 */
 sqlite3_mutex *sqlite3_db_mutex(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return db->mutex;
 }
 
@@ -607,6 +613,10 @@ sqlite3_mutex *sqlite3_db_mutex(sqlite3 *db){
 */
 int sqlite3_db_release_memory(sqlite3 *db){
   int i;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   sqlite3BtreeEnterAll(db);
   for(i=0; i<db->nDb; i++){
@@ -737,6 +747,12 @@ static int nocaseCollatingFunc(
 ** Return the ROWID of the most recent insert
 */
 sqlite_int64 sqlite3_last_insert_rowid(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return db->lastRowid;
 }
 
@@ -744,6 +760,12 @@ sqlite_int64 sqlite3_last_insert_rowid(sqlite3 *db){
 ** Return the number of changes in the most recent call to sqlite3_exec().
 */
 int sqlite3_changes(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return db->nChange;
 }
 
@@ -751,6 +773,12 @@ int sqlite3_changes(sqlite3 *db){
 ** Return the number of changes since the database handle was opened.
 */
 int sqlite3_total_changes(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return db->nTotalChange;
 }
 
@@ -1296,6 +1324,9 @@ int sqlite3_busy_handler(
   int (*xBusy)(void*,int),
   void *pArg
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE;
+#endif
   sqlite3_mutex_enter(db->mutex);
   db->busyHandler.xFunc = xBusy;
   db->busyHandler.pArg = pArg;
@@ -1317,6 +1348,12 @@ void sqlite3_progress_handler(
   int (*xProgress)(void*), 
   void *pArg
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   if( nOps>0 ){
     db->xProgress = xProgress;
@@ -1337,6 +1374,9 @@ void sqlite3_progress_handler(
 ** specified number of milliseconds before returning 0.
 */
 int sqlite3_busy_timeout(sqlite3 *db, int ms){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   if( ms>0 ){
     sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)db);
     db->busyTimeout = ms;
@@ -1350,6 +1390,12 @@ int sqlite3_busy_timeout(sqlite3 *db, int ms){
 ** Cause any pending operation to stop at its earliest opportunity.
 */
 void sqlite3_interrupt(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return;
+  }
+#endif
   db->u1.isInterrupted = 1;
 }
 
@@ -1487,6 +1533,12 @@ int sqlite3_create_function_v2(
 ){
   int rc = SQLITE_ERROR;
   FuncDestructor *pArg = 0;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    return SQLITE_MISUSE_BKPT;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   if( xDestroy ){
     pArg = (FuncDestructor *)sqlite3DbMallocZero(db, sizeof(FuncDestructor));
@@ -1523,6 +1575,10 @@ int sqlite3_create_function16(
 ){
   int rc;
   char *zFunc8;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zFunctionName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1, SQLITE_UTF16NATIVE);
@@ -1554,6 +1610,12 @@ int sqlite3_overload_function(
 ){
   int nName = sqlite3Strlen30(zName);
   int rc = SQLITE_OK;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 || nArg<-2 ){
+    return SQLITE_MISUSE_BKPT;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
     rc = sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
@@ -1575,6 +1637,13 @@ int sqlite3_overload_function(
 */
 void *sqlite3_trace(sqlite3 *db, void (*xTrace)(void*,const char*), void *pArg){
   void *pOld;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pOld = db->pTraceArg;
   db->xTrace = xTrace;
@@ -1596,6 +1665,13 @@ void *sqlite3_profile(
   void *pArg
 ){
   void *pOld;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pOld = db->pProfileArg;
   db->xProfile = xProfile;
@@ -1616,6 +1692,13 @@ void *sqlite3_commit_hook(
   void *pArg                /* Argument to the function */
 ){
   void *pOld;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pOld = db->pCommitArg;
   db->xCommitCallback = xCallback;
@@ -1634,6 +1717,13 @@ void *sqlite3_update_hook(
   void *pArg                /* Argument to the function */
 ){
   void *pRet;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pRet = db->pUpdateArg;
   db->xUpdateCallback = xCallback;
@@ -1652,6 +1742,13 @@ void *sqlite3_rollback_hook(
   void *pArg                /* Argument to the function */
 ){
   void *pRet;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pRet = db->pRollbackArg;
   db->xRollbackCallback = xCallback;
@@ -1698,6 +1795,9 @@ int sqlite3_wal_autocheckpoint(sqlite3 *db, int nFrame){
   UNUSED_PARAMETER(db);
   UNUSED_PARAMETER(nFrame);
 #else
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   if( nFrame>0 ){
     sqlite3_wal_hook(db, sqlite3WalDefaultHook, SQLITE_INT_TO_PTR(nFrame));
   }else{
@@ -1718,6 +1818,12 @@ void *sqlite3_wal_hook(
 ){
 #ifndef SQLITE_OMIT_WAL
   void *pRet;
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   pRet = db->pWalArg;
   db->xWalCallback = xCallback;
@@ -1745,6 +1851,10 @@ int sqlite3_wal_checkpoint_v2(
   int rc;                         /* Return code */
   int iDb = SQLITE_MAX_ATTACHED;  /* sqlite3.aDb[] index of db to checkpoint */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
+
   /* Initialize the output variables to -1 in case an error occurs. */
   if( pnLog ) *pnLog = -1;
   if( pnCkpt ) *pnCkpt = -1;
@@ -2141,6 +2251,12 @@ static const int aHardLimit[] = {
 int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
   int oldLimit;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return -1;
+  }
+#endif
 
   /* EVIDENCE-OF: R-30189-54097 For each limit category SQLITE_LIMIT_NAME
   ** there is a hard upper bound set at compile-time by a C preprocessor
@@ -2426,6 +2542,9 @@ static int openDatabase(
   char *zOpen = 0;                /* Filename argument to pass to BtreeOpen() */
   char *zErrMsg = 0;              /* Error message from sqlite3ParseUri() */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( ppDb==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *ppDb = 0;
 #ifndef SQLITE_OMIT_AUTOINIT
   rc = sqlite3_initialize();
@@ -2715,13 +2834,15 @@ int sqlite3_open16(
   sqlite3_value *pVal;
   int rc;
 
-  assert( zFilename );
-  assert( ppDb );
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( ppDb==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *ppDb = 0;
 #ifndef SQLITE_OMIT_AUTOINIT
   rc = sqlite3_initialize();
   if( rc ) return rc;
 #endif
+  if( zFilename==0 ) zFilename = "\000\000";
   pVal = sqlite3ValueNew(0);
   sqlite3ValueSetStr(pVal, -1, zFilename, SQLITE_UTF16NATIVE, SQLITE_STATIC);
   zFilename8 = sqlite3ValueText(pVal, SQLITE_UTF8);
@@ -2766,6 +2887,10 @@ int sqlite3_create_collation_v2(
   void(*xDel)(void*)
 ){
   int rc;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   rc = createCollation(db, zName, (u8)enc, pCtx, xCompare, xDel);
@@ -2787,6 +2912,10 @@ int sqlite3_create_collation16(
 ){
   int rc = SQLITE_OK;
   char *zName8;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   zName8 = sqlite3Utf16to8(db, zName, -1, SQLITE_UTF16NATIVE);
@@ -2809,6 +2938,9 @@ int sqlite3_collation_needed(
   void *pCollNeededArg, 
   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*)
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   db->xCollNeeded = xCollNeeded;
   db->xCollNeeded16 = 0;
@@ -2827,6 +2959,9 @@ int sqlite3_collation_needed16(
   void *pCollNeededArg, 
   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*)
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   db->xCollNeeded = 0;
   db->xCollNeeded16 = xCollNeeded16;
@@ -2853,6 +2988,12 @@ int sqlite3_global_recover(void){
 ** by the next COMMIT or ROLLBACK.
 */
 int sqlite3_get_autocommit(sqlite3 *db){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   return db->autoCommit;
 }
 
@@ -3035,6 +3176,9 @@ int sqlite3_sleep(int ms){
 ** Enable or disable the extended result codes.
 */
 int sqlite3_extended_result_codes(sqlite3 *db, int onoff){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   db->errMask = onoff ? 0xffffffff : 0xff;
   sqlite3_mutex_leave(db->mutex);
@@ -3048,6 +3192,9 @@ int sqlite3_file_control(sqlite3 *db, const char *zDbName, int op, void *pArg){
   int rc = SQLITE_ERROR;
   Btree *pBtree;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   pBtree = sqlite3DbNameToBtree(db, zDbName);
   if( pBtree ){
@@ -3390,7 +3537,7 @@ int sqlite3_test_control(int op, ...){
 ** returns a NULL pointer.
 */
 const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam){
-  if( zFilename==0 ) return 0;
+  if( zFilename==0 || zParam==0 ) return 0;
   zFilename += sqlite3Strlen30(zFilename) + 1;
   while( zFilename[0] ){
     int x = strcmp(zFilename, zParam);
@@ -3446,6 +3593,12 @@ Btree *sqlite3DbNameToBtree(sqlite3 *db, const char *zDbName){
 ** connection.
 */
 const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   Btree *pBt = sqlite3DbNameToBtree(db, zDbName);
   return pBt ? sqlite3BtreeGetFilename(pBt) : 0;
 }
@@ -3455,6 +3608,12 @@ const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName){
 ** no such database exists.
 */
 int sqlite3_db_readonly(sqlite3 *db, const char *zDbName){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return -1;
+  }
+#endif
   Btree *pBt = sqlite3DbNameToBtree(db, zDbName);
   return pBt ? sqlite3BtreeIsReadonly(pBt) : -1;
 }
diff --git a/src/malloc.c b/src/malloc.c
index 6fb9d53d1..c3c644fd6 100644
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -475,6 +475,9 @@ sqlite3_uint64 sqlite3_msize(void *p){
 ** Free memory previously obtained from sqlite3Malloc().
 */
 void sqlite3_free(void *p){
+#if defined(SQLITE_ENABLE_API_ARMOR) && !defined(SQLITE_OMIT_AUTOINIT)
+  if( sqlite3_initialize() ) return;
+#endif
   if( p==0 ) return;  /* IMP: R-49053-54554 */
   assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
   assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) );
diff --git a/src/mutex_unix.c b/src/mutex_unix.c
index c8663144e..c936914d8 100644
--- a/src/mutex_unix.c
+++ b/src/mutex_unix.c
@@ -175,8 +175,12 @@ static sqlite3_mutex *pthreadMutexAlloc(int iType){
       break;
     }
     default: {
-      assert( iType-2 >= 0 );
-      assert( iType-2 < ArraySize(staticMutexes) );
+#ifdef SQLITE_ENABLE_API_ARMOR
+      if( iType-2<0 || iType-2>=ArraySize(staticMutexes) ){
+        (void)SQLITE_MISUSE_BKPT;
+        return 0;
+      }
+#endif
       p = &staticMutexes[iType-2];
 #if SQLITE_MUTEX_NREF
       p->id = iType;
diff --git a/src/os.c b/src/os.c
index b6c28a1dc..2a2cf13c5 100644
--- a/src/os.c
+++ b/src/os.c
@@ -361,6 +361,10 @@ int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
   int rc = sqlite3_initialize();
   if( rc ) return rc;
 #endif
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( pVfs==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+
   MUTEX_LOGIC( mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
   sqlite3_mutex_enter(mutex);
   vfsUnlink(pVfs);
diff --git a/src/prepare.c b/src/prepare.c
index a05e619f3..ca9c64b44 100644
--- a/src/prepare.c
+++ b/src/prepare.c
@@ -709,9 +709,12 @@ static int sqlite3LockAndPrepare(
   const char **pzTail       /* OUT: End of parsed string */
 ){
   int rc;
-  assert( ppStmt!=0 );
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( ppStmt==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *ppStmt = 0;
-  if( !sqlite3SafetyCheckOk(db) ){
+  if( !sqlite3SafetyCheckOk(db)||zSql==0 ){
     return SQLITE_MISUSE_BKPT;
   }
   sqlite3_mutex_enter(db->mutex);
@@ -818,9 +821,11 @@ static int sqlite3Prepare16(
   const char *zTail8 = 0;
   int rc = SQLITE_OK;
 
-  assert( ppStmt );
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( ppStmt==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *ppStmt = 0;
-  if( !sqlite3SafetyCheckOk(db) ){
+  if( !sqlite3SafetyCheckOk(db)||zSql==0 ){
     return SQLITE_MISUSE_BKPT;
   }
   if( nBytes>=0 ){
diff --git a/src/printf.c b/src/printf.c
index 1df287fbb..f000da7fc 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -223,6 +223,13 @@ void sqlite3VXPrintf(
   PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
   char buf[etBUFSIZE];       /* Conversion buffer */
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( ap==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    sqlite3StrAccumReset(pAccum);
+    return;
+  }
+#endif
   bufpt = 0;
   if( bFlags ){
     if( (bArgList = (bFlags & SQLITE_PRINTF_SQLFUNC))!=0 ){
@@ -943,6 +950,13 @@ char *sqlite3_vmprintf(const char *zFormat, va_list ap){
   char *z;
   char zBase[SQLITE_PRINT_BUF_SIZE];
   StrAccum acc;
+
+#ifdef SQLITE_ENABLE_API_ARMOR  
+  if( zFormat==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
 #ifndef SQLITE_OMIT_AUTOINIT
   if( sqlite3_initialize() ) return 0;
 #endif
@@ -985,6 +999,13 @@ char *sqlite3_mprintf(const char *zFormat, ...){
 char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
   StrAccum acc;
   if( n<=0 ) return zBuf;
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( zBuf==0 || zFormat==0 ) {
+    (void)SQLITE_MISUSE_BKPT;
+    if( zBuf && n>0 ) zBuf[0] = 0;
+    return zBuf;
+  }
+#endif
   sqlite3StrAccumInit(&acc, zBuf, n, 0);
   acc.useMalloc = 0;
   sqlite3VXPrintf(&acc, 0, zFormat, ap);
diff --git a/src/random.c b/src/random.c
index b82566524..7bca0d71a 100644
--- a/src/random.c
+++ b/src/random.c
@@ -34,6 +34,11 @@ void sqlite3_randomness(int N, void *pBuf){
   unsigned char t;
   unsigned char *zBuf = pBuf;
 
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return;
+#endif
+  if( pBuf==0 || N<=0 ) return;
+
   /* The "wsdPrng" macro will resolve to the pseudo-random number generator
   ** state vector.  If writable static data is unsupported on the target,
   ** we have to locate the state vector at run-time.  In the more common
@@ -52,12 +57,6 @@ void sqlite3_randomness(int N, void *pBuf){
   sqlite3_mutex_enter(mutex);
 #endif
 
-  if( N<=0 ){
-    wsdPrng.isInit = 0;
-    sqlite3_mutex_leave(mutex);
-    return;
-  }
-
   /* Initialize the state of the random number generator once,
   ** the first time this routine is called.  The seed value does
   ** not need to contain a lot of randomness since we are not
diff --git a/src/status.c b/src/status.c
index 79a8001b8..4c2eabb66 100644
--- a/src/status.c
+++ b/src/status.c
@@ -86,6 +86,9 @@ int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
   if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
     return SQLITE_MISUSE_BKPT;
   }
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *pCurrent = wsdStat.nowValue[op];
   *pHighwater = wsdStat.mxValue[op];
   if( resetFlag ){
@@ -105,6 +108,11 @@ int sqlite3_db_status(
   int resetFlag         /* Reset high-water mark if true */
 ){
   int rc = SQLITE_OK;   /* Return code */
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){
+    return SQLITE_MISUSE_BKPT;
+  }
+#endif
   sqlite3_mutex_enter(db->mutex);
   switch( op ){
     case SQLITE_DBSTATUS_LOOKASIDE_USED: {
diff --git a/src/table.c b/src/table.c
index c435b2bc0..6e1df3064 100644
--- a/src/table.c
+++ b/src/table.c
@@ -126,6 +126,9 @@ int sqlite3_get_table(
   int rc;
   TabResult res;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( pazResult==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   *pazResult = 0;
   if( pnColumn ) *pnColumn = 0;
   if( pnRow ) *pnRow = 0;
diff --git a/src/util.c b/src/util.c
index 9bb8d8915..ab409fa25 100644
--- a/src/util.c
+++ b/src/util.c
@@ -251,6 +251,11 @@ int sqlite3Dequote(char *z){
 */
 int sqlite3_stricmp(const char *zLeft, const char *zRight){
   register unsigned char *a, *b;
+  if( zLeft==0 ){
+    return zRight ? -1 : 0;
+  }else if( zRight==0 ){
+    return 1;
+  }
   a = (unsigned char *)zLeft;
   b = (unsigned char *)zRight;
   while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
@@ -258,6 +263,11 @@ int sqlite3_stricmp(const char *zLeft, const char *zRight){
 }
 int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
   register unsigned char *a, *b;
+  if( zLeft==0 ){
+    return zRight ? -1 : 0;
+  }else if( zRight==0 ){
+    return 1;
+  }
   a = (unsigned char *)zLeft;
   b = (unsigned char *)zRight;
   while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
diff --git a/src/vdbeapi.c b/src/vdbeapi.c
index 0ab76e078..daf7b101d 100644
--- a/src/vdbeapi.c
+++ b/src/vdbeapi.c
@@ -966,11 +966,19 @@ static const void *columnName(
   const void *(*xFunc)(Mem*),
   int useType
 ){
-  const void *ret = 0;
-  Vdbe *p = (Vdbe *)pStmt;
+  const void *ret;
+  Vdbe *p;
   int n;
-  sqlite3 *db = p->db;
-  
+  sqlite3 *db;
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( pStmt==0 ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
+  ret = 0;
+  p = (Vdbe *)pStmt;
+  db = p->db;
   assert( db!=0 );
   n = sqlite3_column_count(pStmt);
   if( N<n && N>=0 ){
@@ -1435,6 +1443,12 @@ int sqlite3_stmt_busy(sqlite3_stmt *pStmt){
 */
 sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){
   sqlite3_stmt *pNext;
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(pDb) ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
   sqlite3_mutex_enter(pDb->mutex);
   if( pStmt==0 ){
     pNext = (sqlite3_stmt*)pDb->pVdbe;
@@ -1450,7 +1464,14 @@ sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){
 */
 int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
   Vdbe *pVdbe = (Vdbe*)pStmt;
-  u32 v = pVdbe->aCounter[op];
+  u32 v;
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !pStmt ){
+    (void)SQLITE_MISUSE_BKPT;
+    return 0;
+  }
+#endif
+  v = pVdbe->aCounter[op];
   if( resetFlag ) pVdbe->aCounter[op] = 0;
   return (int)v;
 }
diff --git a/src/vdbeblob.c b/src/vdbeblob.c
index 71bd8816d..0cf2b0652 100644
--- a/src/vdbeblob.c
+++ b/src/vdbeblob.c
@@ -153,6 +153,11 @@ int sqlite3_blob_open(
   Parse *pParse = 0;
   Incrblob *pBlob = 0;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || ppBlob==0 || zTable==0 ){
+    return SQLITE_MISUSE_BKPT;
+  }
+#endif
   flags = !!flags;                /* flags = (flags ? 1 : 0); */
   *ppBlob = 0;
 
diff --git a/src/vtab.c b/src/vtab.c
index faee4ae47..334de9aac 100644
--- a/src/vtab.c
+++ b/src/vtab.c
@@ -81,6 +81,9 @@ int sqlite3_create_module(
   const sqlite3_module *pModule,  /* The definition of the module */
   void *pAux                      /* Context pointer for xCreate/xConnect */
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   return createModule(db, zName, pModule, pAux, 0);
 }
 
@@ -94,6 +97,9 @@ int sqlite3_create_module_v2(
   void *pAux,                     /* Context pointer for xCreate/xConnect */
   void (*xDestroy)(void *)        /* Module destructor function */
 ){
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
   return createModule(db, zName, pModule, pAux, xDestroy);
 }
 
@@ -698,6 +704,9 @@ int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
   Table *pTab;
   char *zErr = 0;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
   if( !db->pVtabCtx || !(pTab = db->pVtabCtx->pTab) ){
     sqlite3Error(db, SQLITE_MISUSE);
@@ -1054,6 +1063,9 @@ int sqlite3_vtab_on_conflict(sqlite3 *db){
   static const unsigned char aMap[] = { 
     SQLITE_ROLLBACK, SQLITE_ABORT, SQLITE_FAIL, SQLITE_IGNORE, SQLITE_REPLACE 
   };
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   assert( OE_Rollback==1 && OE_Abort==2 && OE_Fail==3 );
   assert( OE_Ignore==4 && OE_Replace==5 );
   assert( db->vtabOnConflict>=1 && db->vtabOnConflict<=5 );
@@ -1069,8 +1081,10 @@ int sqlite3_vtab_config(sqlite3 *db, int op, ...){
   va_list ap;
   int rc = SQLITE_OK;
 
+#ifdef SQLITE_ENABLE_API_ARMOR
+  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
   sqlite3_mutex_enter(db->mutex);
-
   va_start(ap, op);
   switch( op ){
     case SQLITE_VTAB_CONSTRAINT_SUPPORT: {