From 392ecf3352b23bf82576026296798372ed2ec595 Mon Sep 17 00:00:00 2001
From: Aliaksandr <grubian2@gmail.com>
Date: Mon, 23 Mar 2026 17:52:08 +0200
Subject: [PATCH] libldac-dec: fix decoder initialization failure

`ldacBT_init_handle_decode` passes `hLdacBT->cci`, `hLdacBT->frmlen`,
and `hLdacBT->frm_status` to `ldaclib_set_config_info()` before they
are assigned, causing `LDACBT_ERR_FATAL` on every decode init.

This breaks PipeWire 1.6+'s LDAC codec entirely, since the SPA plugin
treats decoder init failure as fatal and refuses to initialize the
encoder too.

Move the struct member assignments before the function call that uses
them.
---
 .../li/libldac-dec/fix-decode-init.patch      | 24 +++++++++++++++++++
 pkgs/by-name/li/libldac-dec/package.nix       |  5 ++++
 2 files changed, 29 insertions(+)
 create mode 100644 pkgs/by-name/li/libldac-dec/fix-decode-init.patch

diff --git a/pkgs/by-name/li/libldac-dec/fix-decode-init.patch b/pkgs/by-name/li/libldac-dec/fix-decode-init.patch
new file mode 100644
index 000000000000..be1b8905e27c
--- /dev/null
+++ b/pkgs/by-name/li/libldac-dec/fix-decode-init.patch
@@ -0,0 +1,24 @@
+--- a/src/ldacBT_api.o.c
++++ b/src/ldacBT_api.o.c
+@@ -165,6 +165,10 @@
+   // tbl_ldacbt_config[0].frmlen_1ch;
+   // frmlen = 165 * channel - LDACBT_FRMHDRBYTES;
+   frmlen = tbl_ldacbt_config[0].frmlen_1ch * channel - LDACBT_FRMHDRBYTES;
++  hLdacBT->frmlen = frmlen;
++  hLdacBT->cm = cm;
++  hLdacBT->cci = cci;
++  hLdacBT->frm_status = 0;
+   /* Set Configuration Information */
+   result = ldaclib_set_config_info(
+       hLdacBT->hLDAC, hLdacBT->sfid, hLdacBT->cci, hLdacBT->frmlen, hLdacBT->frm_status);
+@@ -174,10 +178,6 @@
+   } else if (result != LDAC_S_OK) {
+     hLdacBT->error_code_api = LDACBT_GET_LDACLIB_ERROR_CODE;
+   }
+-  hLdacBT->frmlen = frmlen;
+-  hLdacBT->cm = cm;
+-  hLdacBT->cci = cci;
+-  hLdacBT->frm_status = 0;
+   hLdacBT->sfid = sfid;
+   result = ldaclib_init_decode(hLdacBT->hLDAC, nshift);
+   if (LDAC_FAILED(result)) {
diff --git a/pkgs/by-name/li/libldac-dec/package.nix b/pkgs/by-name/li/libldac-dec/package.nix
index 7a8eaf208718..5d292af9996f 100644
--- a/pkgs/by-name/li/libldac-dec/package.nix
+++ b/pkgs/by-name/li/libldac-dec/package.nix
@@ -17,6 +17,11 @@ stdenv.mkDerivation {
     hash = "sha256-pdeEtQXxL2pd9qTfLOEmPDn3POgo5qxRqbK807WN98s=";
   };
 
+  patches = [
+    # Fix uninitialized struct members passed to ldaclib_set_config_info in decode init
+    ./fix-decode-init.patch
+  ];
+
   nativeBuildInputs = [ cmake ];
 
   # Upstream CMakeLists.txt doesn't have install rules