support for Xephyr screen size

1 files changed, 26 insertions, 0 deletions

diff --git a/src/firejail/x11.c b/src/firejail/x11.c
index 2e2e3dff2..c6bb7e1e3 100644
--- a/src/firejail/x11.c
+++ b/src/firejail/x11.c
@@ -398,6 +398,27 @@ void x11_start_xvfb(int argc, char **argv) {
 }
 
 
+
+static char *extract_setting(int argc, char **argv, const char *argument) {
+        int i;
+        int len = strlen(argument);
+
+        for (i = 1; i < argc; i++) {
+                if (strncmp(argv[i], argument, len) == 0) {
+                        return argv[i] + len;
+                }
+
+                // detect end of firejail params
+                if (strcmp(argv[i], "--") == 0)
+                        break;
+                if (strncmp(argv[i], "--", 2) != 0)
+                        break;
+        }
+
+        return NULL;
+}
+
+
 //$ Xephyr -ac -br -noreset -screen 800x600 :22 &
 //$ DISPLAY=:22 firejail --net=eth0 --blacklist=/tmp/.X11-unix/x0 firefox
 void x11_start_xephyr(int argc, char **argv) {
@@ -407,6 +428,11 @@ void x11_start_xephyr(int argc, char **argv) {
         pid_t jail = 0;
         pid_t server = 0;
 
+        // default xephyr screen can be overwriten by a --xephyr-screen= command line option
+        char *newscreen = extract_setting(argc, argv, "--xephyr-screen=");
+        if (newscreen)
+                xephyr_screen = newscreen;
+
         setenv("FIREJAIL_X11", "yes", 1);
 
         // unfortunately, xephyr does a number of weird things when started by root user!!!