From eed0bc3ebd15bf94a28ca019ab656a3a0bc0d258 Mon Sep 17 00:00:00 2001
From: Arkadiusz Hiler <arek@hiler.eu>
Date: Sun, 30 Sep 2018 15:11:24 +0300
Subject: [PATCH] Add support for installing binaries with DT_RPATH

It's better to use DT_RPATH dynamic section of the elf binary to store
the paths of libraries to load instead of overwriting LD_LIBRARY_PATH
for the whole environment, causing surprises. This solution is much more
transparent and perfectly suitable for running contained installations
of wayland/wlroots/sway.

The code unsetting the LD_LIBRARY_PATH/LD_PRELOAD was also deleted as
it's a placebo security at best - we should trust the execution path
that leads us to running sway, and it's way too late to care about those
variables since we already started executing our compositor, thus we
would be compromised anyway.
---
 meson.build          | 11 ++++++++++-
 meson_options.txt    |  3 ++-
 sway/main.c          |  8 --------
 sway/meson.build     |  1 +
 swaybar/meson.build  |  1 +
 swaybg/meson.build   |  1 +
 swayidle/meson.build |  1 +
 swaylock/meson.build |  1 +
 swaymsg/meson.build  |  1 +
 swaynag/meson.build  |  1 +
 10 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/meson.build b/meson.build
index 080709fa1..1e7ce281a 100644
--- a/meson.build
+++ b/meson.build
@@ -128,7 +128,16 @@ else
 endif
 add_project_arguments('-DSWAY_VERSION=@0@'.format(version), language: 'c')
 
-add_project_arguments('-D_LD_LIBRARY_PATH="@0@"'.format(get_option('ld-library-path')), language: 'c')
+if get_option('use_rpath')
+	if get_option('custom_rpath') == ''
+		# default to platform specific libdir, one level up from the binary
+		rpathdir = join_paths('$ORIGIN', '..', '$LIB')
+	else
+		rpathdir = get_option('custom_rpath')
+	endif
+else
+	rpathdir = ''
+endif
 
 sway_inc = include_directories('include')
 
diff --git a/meson_options.txt b/meson_options.txt
index 50d646fd3..2db852fc7 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -1,5 +1,6 @@
 option('sway-version', type : 'string', description: 'The version string reported in `sway --version`.')
-option('ld-library-path', type: 'string', value: '', description: 'The LD_LIBRARY_PATH environment variable.')
+option('use_rpath', type: 'boolean', value: false, description: 'install binaries with rpath set')
+option('custom_rpath', type: 'string', value: '', description: 'override rpath with a custom one')
 option('default-wallpaper', type: 'boolean', value: true, description: 'Install the default wallpaper.')
 option('zsh-completions', type: 'boolean', value: true, description: 'Install zsh shell completions.')
 option('bash-completions', type: 'boolean', value: true, description: 'Install bash shell completions.')
diff --git a/sway/main.c b/sway/main.c
index 50b05b217..dea4a31c3 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -241,14 +241,6 @@ int main(int argc, char **argv) {
 		"      --get-socketpath   Gets the IPC socket path and prints it, then exits.\n"
 		"\n";
 
-	// Security:
-	unsetenv("LD_PRELOAD");
-#ifdef _LD_LIBRARY_PATH
-	setenv("LD_LIBRARY_PATH", _LD_LIBRARY_PATH, 1);
-#else
-	unsetenv("LD_LIBRARY_PATH");
-#endif
-
 	int c;
 	while (1) {
 		int option_index = 0;
diff --git a/sway/meson.build b/sway/meson.build
index b6394ecb8..6eb9a9d7a 100644
--- a/sway/meson.build
+++ b/sway/meson.build
@@ -187,5 +187,6 @@ executable(
 	include_directories: [sway_inc],
 	dependencies: sway_deps,
 	link_with: [lib_sway_common],
+	install_rpath : rpathdir,
 	install: true
 )
diff --git a/swaybar/meson.build b/swaybar/meson.build
index d65edb11e..7a02a33f3 100644
--- a/swaybar/meson.build
+++ b/swaybar/meson.build
@@ -24,5 +24,6 @@ executable(
 		wlroots,
 	],
 	link_with: [lib_sway_common, lib_sway_client],
+	install_rpath : rpathdir,
 	install: true
 )
diff --git a/swaybg/meson.build b/swaybg/meson.build
index 8704de6d3..095c54884 100644
--- a/swaybg/meson.build
+++ b/swaybg/meson.build
@@ -14,5 +14,6 @@ executable(
 		wlroots,
 	],
 	link_with: [lib_sway_common, lib_sway_client],
+	install_rpath : rpathdir,
 	install: true
 )
diff --git a/swayidle/meson.build b/swayidle/meson.build
index f62545f8b..6c3ac1193 100644
--- a/swayidle/meson.build
+++ b/swayidle/meson.build
@@ -14,5 +14,6 @@ executable(
 		swayidle_deps,
 	],
 	link_with: [lib_sway_common, lib_sway_client],
+	install_rpath : rpathdir,
 	install: true
 )
diff --git a/swaylock/meson.build b/swaylock/meson.build
index 6c87d173d..6605340b4 100644
--- a/swaylock/meson.build
+++ b/swaylock/meson.build
@@ -33,6 +33,7 @@ executable('swaylock',
 	include_directories: [sway_inc],
 	dependencies: dependencies,
 	link_with: [lib_sway_common, lib_sway_client],
+	install_rpath : rpathdir,
 	install: true
 )
 
diff --git a/swaymsg/meson.build b/swaymsg/meson.build
index 8638b838d..7318349d5 100644
--- a/swaymsg/meson.build
+++ b/swaymsg/meson.build
@@ -4,5 +4,6 @@ executable(
     include_directories: [sway_inc],
     dependencies: [jsonc, wlroots],
     link_with: [lib_sway_common],
+    install_rpath : rpathdir,
     install: true
 )
diff --git a/swaynag/meson.build b/swaynag/meson.build
index 2ba3ed95f..223a0bc77 100644
--- a/swaynag/meson.build
+++ b/swaynag/meson.build
@@ -19,5 +19,6 @@ executable(
 		wlroots,
 	],
 	link_with: [lib_sway_common, lib_sway_client],
+	install_rpath : rpathdir,
 	install: true
 )