From 20bcf64f169f356139c485cd6c636f2a17e7e65a Mon Sep 17 00:00:00 2001
From: vkc-1974 <44870873+vkc-1974@users.noreply.github.com>
Date: Mon, 6 Dec 2021 03:47:03 +0300
Subject: [PATCH] Initial release

---
 Makefile           | 19 +++++++++++++++++++
 README.md          | 25 ++++++++++++++++++++++++-
 libc_dlopen_mode.c | 17 +++++++++++++++++
 version.map        |  4 ++++
 4 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 Makefile
 create mode 100644 libc_dlopen_mode.c
 create mode 100644 version.map

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a3297cb
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,19 @@
+.PHONY: all clean
+
+RES_LIB_NAME	=	liblibc_dlopen_mode
+RES_LIB			=	$(RES_LIB_NAME).so
+SRCS			=	\
+	libc_dlopen_mode.c
+
+CFLAGS	+=	-fpic -shared -flto -Wl,--version-script -Wl,version.map -Wl,--as-needed
+
+#
+# Add `--save-temp` to collect more details about created shared library
+
+all: $(RES_LIB)
+
+$(RES_LIB): $(SRCS) version.map
+	$(CC) $(CFLAGS) -o $@ $(SRCS)
+
+clean:
+	$(RM) $(RES_LIB)
diff --git a/README.md b/README.md
index 8f461bf..48194ff 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,25 @@
 # XCOM2WotC-f35
-Small shared library to fix glibc compatibility issue to Steam's XCOM2 WotC game for Fedora 35 (and above i hope)
+Small shared library to fix glibc compatibility issue to Steam's XCOM2 WotC game for Fedora 35 (and above i hope).
+Unfortunately `XCOM2WotC` binary executable was built in a bit wrong way and adeded the referencese to GLibC's
+private functions (since GLibC 2.34). I hope it will be fixed by product development team soon.
+If you are lucky enough ;) (like me) and have updated your Fedora Linux to 35 you can use a small trick given project
+provides: it just creates synonyms to GLibC's public functions; you just need to build a shared library ask dynamic
+linker to preload it  so that `XCOM2WotC` application could use missing routines.
+
+## Build
+
+make
+
+## Preload activation
+
+There are two way to do it:
+
+* using of LD_PRELOAD environment variable (e.g. export LD_PRELOAD=<full-path-to-liblibc_dlopen_mode.so>)
+* update `Steam/steamapps/common/XCOM 2/XCOM2WotC/XCOM2WotC.sh` shell script used by `steam` application to start the game running:
+  look for `LD_PRELOAD_ADDITIONS=` instruction and add the path to `liblibc_dlopen_mode.so` library there
+  
+## Known issues
+
+Unfortunately space symbols in the path to `liblibc_dlopen_mode.so` library are not supported by `Steam/steamapps/common/XCOM 2/XCOM2WotC/XCOM2WotC.sh`
+script out of the box. I am quite lazy to look for a solution as i am happy enough with given fix.
+
diff --git a/libc_dlopen_mode.c b/libc_dlopen_mode.c
new file mode 100644
index 0000000..4a6c610
--- /dev/null
+++ b/libc_dlopen_mode.c
@@ -0,0 +1,17 @@
+// File		:libc_dlopen_mode.c
+// Author	:mouse197410
+// Created	:Mon Dec  6 01:53:56 2021
+#include <dlfcn.h>
+
+__attribute__((__symver__("__libc_dlopen_mode@GLIBC_PRIVATE")))
+void* libc_dlopen_mode(const char *filename, int flags)
+{
+    return dlopen(filename, flags);
+}
+
+__attribute__((__symver__("__libc_dlsym@GLIBC_PRIVATE")))
+void *libc_dlsym(void *restrict handle, const char *restrict symbol)
+{
+    return dlsym(handle, symbol);
+}
+
diff --git a/version.map b/version.map
new file mode 100644
index 0000000..b8361e9
--- /dev/null
+++ b/version.map
@@ -0,0 +1,4 @@
+GLIBC_PRIVATE {
+global:
+    *;
+};