commit 16c435dee5c07567b87620e7396a0a983ad7ec9e
Author: Louis Burda <quent.burda@gmail.com>
Date: Fri, 2 Oct 2020 14:17:19 +0200
Initial prototype
Diffstat:
4 files changed, 238 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1 @@
+winpreload.so
diff --git a/README b/README
@@ -0,0 +1,13 @@
+winpreload
+==========
+
+
+Ideology
+--------
+
+Winpreload is a non-invasive way of modifying window properties for
+windows created by a program through the use of LD_PRELOAD. This
+enables the user to set properties such as _NET_WM_WINDOW_TYPE to
+start the window as floating and adjust its position. Parameters
+are passed to winpreload via environment variables, which are
+prefixed with 'WINPRELOAD+'.
diff --git a/makefile b/makefile
@@ -0,0 +1,5 @@
+CFLAGS = -nostartfiles -fPIC -shared -Wl,-soname,xwrap.so
+LDLIBS = -ldl -lX11
+
+winpreload.so: winpreload.c
+ $(CC) -o $@ $< $(CFLAGS) $(LDLIBS)
diff --git a/winpreload.c b/winpreload.c
@@ -0,0 +1,219 @@
+/* code by https://www.mail-archive.com/devel@xfree86.org/msg05806.html */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <X11/Xlib.h>
+#include <X11/X.h>
+#include <X11/Xatom.h>
+
+/* prototypes */
+static void __e_hack_set_properties(Display *display, Window window);
+
+/* dlopened xlib so we can find the symbols in the real xlib to call them */
+static void *lib_xlib = NULL;
+
+/* the function that actually sets the properties on toplevel window */
+static void
+__e_hack_set_properties(Display *display, Window window)
+{
+ static Atom a_launch_id = 0;
+ static Atom a_launch_path = 0;
+ static Atom a_user_id = 0;
+ static Atom a_process_id = 0;
+ static Atom a_p_process_id = 0;
+ static Atom a_machine_name = 0;
+ static Atom a_user_name = 0;
+ char *env = NULL;
+
+ if (!a_launch_id) a_launch_id = XInternAtom(display, "_E_HACK_LAUNCH_ID", False);
+ if (!a_launch_path) a_launch_path = XInternAtom(display, "_E_HACK_LAUNCH_PATH", False);
+ if (!a_user_id) a_user_id = XInternAtom(display, "_E_HACK_USER_ID", False);
+ if (!a_process_id) a_process_id = XInternAtom(display, "_E_HACK_PROCESS_ID", False);
+ if (!a_p_process_id) a_p_process_id = XInternAtom(display, "_E_HACK_PARENT_PROCESS_ID", False);
+ if (!a_machine_name) a_machine_name = XInternAtom(display, "_E_HACK_MACHINE_NAME", False);
+ if (!a_user_name) a_user_name = XInternAtom(display, "_E_HACK_USER_NAME", False);
+
+ if ((env = getenv("E_HACK_LAUNCH_ID")))
+ XChangeProperty(display, window, a_launch_id, XA_STRING, 8, PropModeReplace, env, strlen(env));
+ if ((env = getenv("E_HACK_LAUNCH_PATH")))
+ XChangeProperty(display, window, a_launch_path, XA_STRING, 8, PropModeReplace, env, strlen(env));
+ {
+ uid_t uid;
+ pid_t pid, ppid;
+ struct utsname ubuf;
+ char buf[4096];
+
+ uid = getuid();
+ pid = getpid();
+ ppid = getppid();
+
+ snprintf(buf, sizeof(buf), "%i", uid);
+ XChangeProperty(display, window, a_user_id, XA_STRING, 8, PropModeReplace, buf, strlen(buf));
+ snprintf(buf, sizeof(buf), "%i", pid);
+ XChangeProperty(display, window, a_process_id, XA_STRING, 8, PropModeReplace, buf, strlen(buf));
+ snprintf(buf, sizeof(buf), "%i", ppid);
+ XChangeProperty(display, window, a_p_process_id, XA_STRING, 8, PropModeReplace, buf, strlen(buf));
+ if (!uname(&ubuf))
+ {
+ snprintf(buf, sizeof(buf), "%s", ubuf.nodename);
+ XChangeProperty(display, window, a_machine_name, XA_STRING, 8, PropModeReplace, buf, strlen(buf));
+ }
+ else
+ XChangeProperty(display, window, a_machine_name, XA_STRING, 8, PropModeReplace, " ", 1);
+ }
+ if ((env = getenv("USER")))
+ XChangeProperty(display, window, a_user_name, XA_STRING, 8, PropModeReplace, env, strlen(env));
+}
+
+/* XCreateWindow intercept hack */
+Window
+XCreateWindow(
+ Display *display,
+ Window parent,
+ int x, int y,
+ unsigned int width, unsigned int height,
+ unsigned int border_width,
+ int depth,
+ unsigned int class,
+ Visual *visual,
+ unsigned long valuemask,
+ XSetWindowAttributes *attributes
+ )
+{
+ static Window (*func)
+ (
+ Display *display,
+ Window parent,
+ int x, int y,
+ unsigned int width, unsigned int height,
+ unsigned int border_width,
+ int depth,
+ unsigned int class,
+ Visual *visual,
+ unsigned long valuemask,
+ XSetWindowAttributes *attributes
+ ) = NULL;
+ int i;
+
+ /* find the real Xlib and the real X function */
+ if (!lib_xlib) lib_xlib = dlopen("libX11.so", RTLD_GLOBAL | RTLD_LAZY);
+ if (!func) func = dlsym (lib_xlib, "XCreateWindow");
+
+ /* multihead screen handling loop */
+ for (i = 0; i < ScreenCount(display); i++)
+ {
+ /* if the window is created as a toplevel window */
+ if (parent == RootWindow(display, i))
+ {
+ Window window;
+
+ /* create it */
+ window = (*func) (display, parent, x, y, width, height,
+ border_width, depth, class, visual, valuemask,
+ attributes);
+ /* set properties */
+ __e_hack_set_properties(display, window);
+ /* return it */
+ return window;
+ }
+ }
+ /* normal child window - create as usual */
+ return (*func) (display, parent, x, y, width, height, border_width, depth,
+ class, visual, valuemask, attributes);
+}
+
+/* XCreateSimpleWindow intercept hack */
+Window
+XCreateSimpleWindow(
+ Display *display,
+ Window parent,
+ int x, int y,
+ unsigned int width, unsigned int height,
+ unsigned int border_width,
+ unsigned long border,
+ unsigned long background
+ )
+{
+ static Window (*func)
+ (
+ Display *display,
+ Window parent,
+ int x, int y,
+ unsigned int width, unsigned int height,
+ unsigned int border_width,
+ unsigned long border,
+ unsigned long background
+ ) = NULL;
+ int i;
+
+ /* find the real Xlib and the real X function */
+ if (!lib_xlib) lib_xlib = dlopen("libX11.so", RTLD_GLOBAL | RTLD_LAZY);
+ if (!func) func = dlsym (lib_xlib, "XCreateSimpleWindow");
+
+ /* multihead screen handling loop */
+ for (i = 0; i < ScreenCount(display); i++)
+ {
+ /* if the window is created as a toplevel window */
+ if (parent == RootWindow(display, i))
+ {
+ Window window;
+
+ /* create it */
+ window = (*func) (display, parent, x, y, width, height,
+ border_width, border, background);
+ /* set properties */
+ __e_hack_set_properties(display, window);
+ /* return it */
+ return window;
+ }
+ }
+ /* normal child window - create as usual */
+ return (*func) (display, parent, x, y, width, height,
+ border_width, border, background);
+}
+
+/* XReparentWindow intercept hack */
+int
+XReparentWindow(
+ Display *display,
+ Window window,
+ Window parent,
+ int x, int y
+ )
+{
+ static int (*func)
+ (
+ Display *display,
+ Window window,
+ Window parent,
+ int x, int y
+ ) = NULL;
+ int i;
+
+ /* find the real Xlib and the real X function */
+ if (!lib_xlib) lib_xlib = dlopen("libX11.so", RTLD_GLOBAL | RTLD_LAZY);
+ if (!func) func = dlsym (lib_xlib, "XReparentWindow");
+
+ /* multihead screen handling loop */
+ for (i = 0; i < ScreenCount(display); i++)
+ {
+ /* if the window is created as a toplevel window */
+ if (parent == RootWindow(display, i))
+ {
+ /* set properties */
+ __e_hack_set_properties(display, window);
+ /* reparent it */
+ return (*func) (display, window, parent, x, y);
+ }
+ }
+ /* normal child window reparenting - reparent as usual */
+ return (*func) (display, window, parent, x, y);
+}
+
