From b57aa88291910689aeaa83ff40dd02c50ab8199b Mon Sep 17 00:00:00 2001
From: Aidan Gauland <aidalgol@fastmail.net>
Date: Sun, 19 May 2024 17:27:59 +1200
Subject: [PATCH] libXNVCtrl: build shared library

The libXNVCtrl library is used by several programs in nixpkgs to get
Nvidia GPU stats, and they all load the library dynamically, but the
libXNVCtrl package only builds a static library.  There is no build flag
to enable this, so we have to patch the Makefile to produce a shared
library.

Based on a patch by @negativo17 for Fedora.
https://github.com/negativo17/nvidia-settings/blob/master/nvidia-settings-libXNVCtrl.patch
---
 .../libxnvctrl-build-shared-3xx.patch         | 24 +++++++++++++++++++
 .../nvidia-x11/libxnvctrl-build-shared.patch  | 21 ++++++++++++++++
 .../os-specific/linux/nvidia-x11/settings.nix |  9 +++++++
 3 files changed, 54 insertions(+)
 create mode 100644 pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared-3xx.patch
 create mode 100644 pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared.patch

diff --git a/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared-3xx.patch b/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared-3xx.patch
new file mode 100644
index 000000000000..d2e074add754
--- /dev/null
+++ b/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared-3xx.patch
@@ -0,0 +1,24 @@
+--- a/src/libXNVCtrl/Makefile
++++ b/src/libXNVCtrl/Makefile
+@@ -33,6 +33,8 @@
+ 
+ LIBXNVCTRL = libXNVCtrl.a
+ 
++LIBXNVCTRL_SHARED = $(OUTPUTDIR)/libXNVCtrl.so
++
+ LIBXNVCTRL_PROGRAM_NAME = "libXNVCtrl"
+ 
+ LIBXNVCTRL_VERSION := $(NVIDIA_VERSION)
+@@ -62,6 +64,12 @@
+ $(LIBXNVCTRL) : $(OBJS)
+ 	$(AR) ru $@ $(OBJS)
+ 
++$(LIBXNVCTRL_SHARED): $(LIBXNVCTRL_OBJ)
++	$(RM) $@ $@.*
++	$(CC) -shared -Wl,-soname=$(@F).0 -o $@.0.0.0 $(LDFLAGS) $^ -lXext -lX11
++	ln -s $(@F).0.0.0 $@.0
++	ln -s $(@F).0 $@
++
+ # define the rule to build each object file
+ $(foreach src,$(SRC),$(eval $(call DEFINE_OBJECT_RULE,TARGET,$(src))))
+ 
diff --git a/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared.patch b/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared.patch
new file mode 100644
index 000000000000..ad1dc1eae400
--- /dev/null
+++ b/pkgs/os-specific/linux/nvidia-x11/libxnvctrl-build-shared.patch
@@ -0,0 +1,21 @@
+--- a/src/libXNVCtrl/xnvctrl.mk
++++ b/src/libXNVCtrl/xnvctrl.mk
+@@ -39,6 +39,8 @@
+ 
+ LIBXNVCTRL = $(OUTPUTDIR)/libXNVCtrl.a
+ 
++LIBXNVCTRL_SHARED = $(OUTPUTDIR)/libXNVCtrl.so
++
+ LIBXNVCTRL_SRC = $(XNVCTRL_DIR)/NVCtrl.c
+ 
+ LIBXNVCTRL_OBJ = $(call BUILD_OBJECT_LIST,$(LIBXNVCTRL_SRC))
+@@ -47,3 +49,9 @@
+ 
+ $(LIBXNVCTRL) : $(LIBXNVCTRL_OBJ)
+ 	$(call quiet_cmd,AR) ru $@ $(LIBXNVCTRL_OBJ)
++
++$(LIBXNVCTRL_SHARED): $(LIBXNVCTRL_OBJ)
++	$(RM) $@ $@.*
++	$(CC) -shared -Wl,-soname=$(@F).0 -o $@.0.0.0 $(LDFLAGS) $^ -lXext -lX11
++	ln -s $(@F).0.0.0 $@.0
++	ln -s $(@F).0 $@
diff --git a/pkgs/os-specific/linux/nvidia-x11/settings.nix b/pkgs/os-specific/linux/nvidia-x11/settings.nix
index 2d9dfd81829e..0df0989c123d 100644
--- a/pkgs/os-specific/linux/nvidia-x11/settings.nix
+++ b/pkgs/os-specific/linux/nvidia-x11/settings.nix
@@ -43,6 +43,14 @@ let
 
     makeFlags = [
       "OUTPUTDIR=." # src/libXNVCtrl
+      "libXNVCtrl.a"
+      "libXNVCtrl.so"
+    ];
+
+    patches = [
+      # Patch the Makefile to also produce a shared library.
+      (if lib.versionOlder nvidia_x11.settingsVersion "400" then ./libxnvctrl-build-shared-3xx.patch
+      else ./libxnvctrl-build-shared.patch)
     ];
 
     installPhase = ''
@@ -52,6 +60,7 @@ let
       cp libXNVCtrl.a $out/lib
       cp NVCtrl.h     $out/include/NVCtrl
       cp NVCtrlLib.h  $out/include/NVCtrl
+      cp -P libXNVCtrl.so* $out/lib
     '';
   };