/*
** 2009 August 17
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
**
** The code in this file is used for testing SQLite. It is not part of
** the source code used in production systems.
**
** Specifically, this file tests the effect of errors while initializing
** the various pluggable sub-systems from within sqlite3_initialize().
** If an error occurs in sqlite3_initialize() the following should be
** true:
**
** 1) An error code is returned to the user, and
** 2) A subsequent call to sqlite3_shutdown() calls the shutdown method
** of those subsystems that were initialized, and
** 3) A subsequent call to sqlite3_initialize() attempts to initialize
** the remaining, uninitialized, subsystems.
*/

#include "sqliteInt.h"
#include <string.h>
#if defined(INCLUDE_SQLITE_TCL_H)
# include "sqlite_tcl.h"
#else
# include "tcl.h"
#endif

static struct Wrapped {
 sqlite3_pcache_methods2 pcache;
 sqlite3_mem_methods mem;
 sqlite3_mutex_methods mutex;

 int mem_init; /* True if mem subsystem is initialized */
 int mem_fail; /* True to fail mem subsystem initialization */
 int mutex_init; /* True if mutex subsystem is initialized */
 int mutex_fail; /* True to fail mutex subsystem initialization */
 int pcache_init; /* True if pcache subsystem is initialized */
 int pcache_fail; /* True to fail pcache subsystem initialization */
} wrapped;

static int wrMemInit(void *pAppData){
 int rc;
 if( wrapped.mem_fail ){
 rc = SQLITE_ERROR;
 }else{
 rc = wrapped.mem.xInit(wrapped.mem.pAppData);
 }
 if( rc==SQLITE_OK ){
 wrapped.mem_init = 1;
 }
 return rc;
}
static void wrMemShutdown(void *pAppData){
 wrapped.mem.xShutdown(wrapped.mem.pAppData);
 wrapped.mem_init = 0;
}
static void *wrMemMalloc(int n) {return wrapped.mem.xMalloc(n);}
static void wrMemFree(void *p) {wrapped.mem.xFree(p);}
static void *wrMemRealloc(void *p, int n) {return wrapped.mem.xRealloc(p, n);}
static int wrMemSize(void *p) {return wrapped.mem.xSize(p);}
static int wrMemRoundup(int n) {return wrapped.mem.xRoundup(n);}


static int wrMutexInit(void){
 int rc;
 if( wrapped.mutex_fail ){
 rc = SQLITE_ERROR;
 }else{
 rc = wrapped.mutex.xMutexInit();
 }
 if( rc==SQLITE_OK ){
 wrapped.mutex_init = 1;
 }
 return rc;
}
static int wrMutexEnd(void){
 wrapped.mutex.xMutexEnd();
 wrapped.mutex_init = 0;
 return SQLITE_OK;
}
static sqlite3_mutex *wrMutexAlloc(int e){
 return wrapped.mutex.xMutexAlloc(e);
}
static void wrMutexFree(sqlite3_mutex *p){
 wrapped.mutex.xMutexFree(p);
}
static void wrMutexEnter(sqlite3_mutex *p){
 wrapped.mutex.xMutexEnter(p);
}
static int wrMutexTry(sqlite3_mutex *p){
 return wrapped.mutex.xMutexTry(p);
}
static void wrMutexLeave(sqlite3_mutex *p){
 wrapped.mutex.xMutexLeave(p);
}
static int wrMutexHeld(sqlite3_mutex *p){
 return wrapped.mutex.xMutexHeld(p);
}
static int wrMutexNotheld(sqlite3_mutex *p){
 return wrapped.mutex.xMutexNotheld(p);
}



static int wrPCacheInit(void *pArg){
 int rc;
 if( wrapped.pcache_fail ){
 rc = SQLITE_ERROR;
 }else{
 rc = wrapped.pcache.xInit(wrapped.pcache.pArg);
 }
 if( rc==SQLITE_OK ){
 wrapped.pcache_init = 1;
 }
 return rc;
}
static void wrPCacheShutdown(void *pArg){
 wrapped.pcache.xShutdown(wrapped.pcache.pArg);
 wrapped.pcache_init = 0;
}

static sqlite3_pcache *wrPCacheCreate(int a, int b, int c){
 return wrapped.pcache.xCreate(a, b, c);
} 
static void wrPCacheCachesize(sqlite3_pcache *p, int n){
 wrapped.pcache.xCachesize(p, n);
} 
static int wrPCachePagecount(sqlite3_pcache *p){
 return wrapped.pcache.xPagecount(p);
} 
static sqlite3_pcache_page *wrPCacheFetch(sqlite3_pcache *p, unsigned a, int b){
 return wrapped.pcache.xFetch(p, a, b);
} 
static void wrPCacheUnpin(sqlite3_pcache *p, sqlite3_pcache_page *a, int b){
 wrapped.pcache.xUnpin(p, a, b);
} 
static void wrPCacheRekey(
 sqlite3_pcache *p, 
 sqlite3_pcache_page *a, 
 unsigned b, 
 unsigned c
){
 wrapped.pcache.xRekey(p, a, b, c);
} 
static void wrPCacheTruncate(sqlite3_pcache *p, unsigned a){
 wrapped.pcache.xTruncate(p, a);
} 
static void wrPCacheDestroy(sqlite3_pcache *p){
 wrapped.pcache.xDestroy(p);
} 

static void installInitWrappers(void){
 sqlite3_mutex_methods mutexmethods = {
 wrMutexInit, wrMutexEnd, wrMutexAlloc,
 wrMutexFree, wrMutexEnter, wrMutexTry,
 wrMutexLeave, wrMutexHeld, wrMutexNotheld
 };
 sqlite3_pcache_methods2 pcachemethods = {
 1, 0,
 wrPCacheInit, wrPCacheShutdown, wrPCacheCreate, 
 wrPCacheCachesize, wrPCachePagecount, wrPCacheFetch,
 wrPCacheUnpin, wrPCacheRekey, wrPCacheTruncate, 
 wrPCacheDestroy
 };
 sqlite3_mem_methods memmethods = {
 wrMemMalloc, wrMemFree, wrMemRealloc,
 wrMemSize, wrMemRoundup, wrMemInit,
 wrMemShutdown,
 0
 };

 memset(&wrapped, 0, sizeof(wrapped));

 sqlite3_shutdown();
 sqlite3_config(SQLITE_CONFIG_GETMUTEX, &wrapped.mutex);
 sqlite3_config(SQLITE_CONFIG_GETMALLOC, &wrapped.mem);
 sqlite3_config(SQLITE_CONFIG_GETPCACHE2, &wrapped.pcache);
 sqlite3_config(SQLITE_CONFIG_MUTEX, &mutexmethods);
 sqlite3_config(SQLITE_CONFIG_MALLOC, &memmethods);
 sqlite3_config(SQLITE_CONFIG_PCACHE2, &pcachemethods);
}

static int SQLITE_TCLAPI init_wrapper_install(
 ClientData clientData, /* Unused */
 Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
 int objc, /* Number of arguments */
 Tcl_Obj *CONST objv[] /* Command arguments */
){
 int i;
 installInitWrappers();
 for(i=1; i<objc; i++){
 char *z = Tcl_GetString(objv[i]);
 if( strcmp(z, "mem")==0 ){
 wrapped.mem_fail = 1;
 }else if( strcmp(z, "mutex")==0 ){
 wrapped.mutex_fail = 1;
 }else if( strcmp(z, "pcache")==0 ){
 wrapped.pcache_fail = 1;
 }else{
 Tcl_AppendResult(interp, "Unknown argument: \"", z, "\"");
 return TCL_ERROR;
 }
 }
 return TCL_OK;
}

static int SQLITE_TCLAPI init_wrapper_uninstall(
 ClientData clientData, /* Unused */
 Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
 int objc, /* Number of arguments */
 Tcl_Obj *CONST objv[] /* Command arguments */
){
 if( objc!=1 ){
 Tcl_WrongNumArgs(interp, 1, objv, "");
 return TCL_ERROR;
 }

 sqlite3_shutdown();
 sqlite3_config(SQLITE_CONFIG_MUTEX, &wrapped.mutex);
 sqlite3_config(SQLITE_CONFIG_MALLOC, &wrapped.mem);
 sqlite3_config(SQLITE_CONFIG_PCACHE2, &wrapped.pcache);
 return TCL_OK;
}

static int SQLITE_TCLAPI init_wrapper_clear(
 ClientData clientData, /* Unused */
 Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
 int objc, /* Number of arguments */
 Tcl_Obj *CONST objv[] /* Command arguments */
){
 if( objc!=1 ){
 Tcl_WrongNumArgs(interp, 1, objv, "");
 return TCL_ERROR;
 }

 wrapped.mem_fail = 0;
 wrapped.mutex_fail = 0;
 wrapped.pcache_fail = 0;
 return TCL_OK;
}

static int SQLITE_TCLAPI init_wrapper_query(
 ClientData clientData, /* Unused */
 Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
 int objc, /* Number of arguments */
 Tcl_Obj *CONST objv[] /* Command arguments */
){
 Tcl_Obj *pRet;

 if( objc!=1 ){
 Tcl_WrongNumArgs(interp, 1, objv, "");
 return TCL_ERROR;
 }

 pRet = Tcl_NewObj();
 if( wrapped.mutex_init ){
 Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj("mutex", -1));
 }
 if( wrapped.mem_init ){
 Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj("mem", -1));
 }
 if( wrapped.pcache_init ){
 Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj("pcache", -1));
 }

 Tcl_SetObjResult(interp, pRet);
 return TCL_OK;
}

int Sqlitetest_init_Init(Tcl_Interp *interp){
 static struct {
 char *zName;
 Tcl_ObjCmdProc *xProc;
 } aObjCmd[] = {
 {"init_wrapper_install", init_wrapper_install},
 {"init_wrapper_query", init_wrapper_query },
 {"init_wrapper_uninstall", init_wrapper_uninstall},
 {"init_wrapper_clear", init_wrapper_clear}
 };
 int i;

 for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
 Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
 }

 return TCL_OK;
}