Build statically-linked sqlcipher for Unix

[anoadragon453]

This PR is a direct application of this patch by the Arch Linux community to help fix incompatibilities between sqlcipher and electron 15+. Full context is in #691.

I've just copy/pasted the patch to this PR for easier review, but from what I can see, this changeset is:

• Compiling sqlcipher.so on Linux, whereas before we relied on it being provided by a separate distro package.
• Setting the --enable-tcl=no configure flag when compiling sqlcipher for Mac and Unix.
• Setting the --with-pic=yes configure flag for Linux only.
• Setting RUSTFLAGS=-Clink-arg=-Wl,-Bsymbolic -Clink-arg=-Wl,--exclude-libs,ALL for Linux only.
• Running tclsh on all platforms (previously Linux was excluded).

The implication is that Linux builds will now receive and use a statically-linked version of sqlite instead of relying on distro packages. It may be worth checking with downstream packagers whether this change is OK.

It should also be ensured that the Element Desktop build machines have the appropriate packages installed to handle this new configuration (tclsh is needed now, for instance).

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[turt2live]

I'm not super familiar with a lot of this code, but at a glance it appears it won't work on Windows - can we get some assurances that it appears to build fine for the supported environments?

[dbkr]

Looks fine, but this isn't behind an option or anything so this will make our debian build ship with a statically linked sqlite. If we want to do this, we should remove it as a dependency from the debian package.

[t3chguy]

Looks fine, but this isn't behind an option or anything so this will make our debian build ship with a statically linked sqlite. If we want to do this, we should remove it as a dependency from the debian package.

We'd also need to communicate to all other re-packagers to not depend on sqlcipher

[anoadragon453]

I've now removed libsqlcipher0 as a dependency from the nightly and release Debian packages.

[turt2live]

I defer to Dave on this one

[dbkr]

Seems fine from my PoV then. We should check with whoever has the job of releasing currently.

[t3chguy]

Landing this, it won't be in a release for nearly 3 weeks, have notified known packagers

[HarHarLinks]

I just updated the first time to a nightly that I think has this patch: Element Nightly version: 2022042401 Olm version: 3.2.8 from aur/element-desktop-nightly-bin.

I launched using the desktop file, which does LD_PRELOAD=/usr/lib/libsqlcipher.so exec "/opt/Element-Nightly/element-desktop-nightly". It did not crash instantly, which is good, but upon checking the settings for search indexing, I found:

Error opening the database: DatabaseUnlockError("Invalid passphrase")

I reset the event store, it started indexing, and crashed after ~1 minute.

[anoadragon453]

@HarHarLinks Try removing the LD_PRELOAD= env var. That will force Element Desktop to use the system libsqlcipher again, bypassing the statically-linked one added in this PR, thus causing crashes.

Note that as of about 4 hours ago, this env var has been removed in the element-desktop-nightly-bin AUR package: https://aur.archlinux.org/cgit/aur.git/commit/?h=element-desktop-nightly-bin&id=f2d409a3fee6bdb63ef5fedf122b0e34de78ca96

So you should just be able to update and have it work :)

Edit: And now I realise you just noticed that on the linked issue. Ah well :)