Secondary development of GRDB + SQLCipher

[rakuyoMo]

As I mentioned in #1495 (reply in thread) . I had not tried it myself before. The author said it would not be supported, but that did not mean I could not try it myself~ so I did some work 😏.

Here is some of my attempts, briefly described: it references GRDB.swift and WCDB's sqlcipher binary package through SPM. Then the encryption-related code in GRDB.swift is added to the secondary development package in the form of source code.

You can use the following method to add the secondary development package I made.

.package(url: "https://github.com/RakuyoKit/rakuyokit-ios.git", branch: "feature/grdb+sqlcipher+rak")

This all worked fine, but I ran into trouble when I actually used:

The program is stuck on this line of code. It seems to have encountered a deadlock problem.

#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
  {
    pthread_t self = pthread_self();
    if( p->nRef>0 && pthread_equal(p->owner, self) ){
      p->nRef++;
    }else{
      pthread_mutex_lock(&p->mutex);
      assert( p->nRef==0 );
      p->owner = self;
      p->nRef = 1;
    }
  }
#else
  /* Use the built-in recursive mutexes if they are available.
  */
  pthread_mutex_lock(&p->mutex); // ⬅️ In this line
#if SQLITE_MUTEX_NREF
  assert( p->nRef>0 || p->owner==0 );
  p->owner = pthread_self();
  p->nRef++;
#endif
#endif

I have done as much searching as I can, reading the documentation, comparing the differences between WCDB-sqlcipher and the official sqlcipher source code, but nothing has been found. I looked through the GRDB code and I'm not sure if the part of the code I don't understand is preventing this from working, but my gut tells me it won't. So I'm even more confused as to why this doesn't work.

I have no choice but to turn to the community, hoping that someone who has had the same experience can provide help or some inspiration.

[rakuyoMo]

In order to rule out the possibility that the problem lies with the sqlcipher package I am using, in this reply I will list the sqlcipher packages I have tried and post the problems.

• crazzy263/SQLCipher: It crashes in the following method

  static void pthreadMutexEnter(sqlite3_mutex *p){
      assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );