Work around system restrictions regarding exec

* doc/emacs/android.texi (Android Environment): Document
`android-use-exec-loader'.
* exec/exec1.c (main): Set program group of child process.
* src/android.c (android_rewrite_spawn_argv): New function.
* src/android.h: Update prototypes.
* src/androidfns.c (syms_of_androidfns): New variable
`android_use_exec_loader'.
* src/callproc.c (emacs_spawn): Rewrite the argument vector to
use exec1 if necessary.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/androidfns.c b/src/androidfns.c
index 3367ebdf755..3bd34edd5b9 100644
--- a/src/androidfns.c
+++ b/src/androidfns.c
@@ -3112,6 +3112,20 @@ Note that if you set this, you will no longer be able to quit Emacs
 using the volume down button.  */);
   android_pass_multimedia_buttons_to_system = false;
 
+  DEFVAR_BOOL ("android-use-exec-loader", android_use_exec_loader,
+    doc: /* Whether or not to bypass system restrictions on program execution.
+
+Android 10 and later prevent programs from executing files installed
+in writable directories, such as the application data directory.
+
+When non-nil, Emacs will bypass this restriction by running such
+executables under system call tracing, and replacing the `execve'
+system call with a version which ignores the system's security
+restrictions.
+
+This option has no effect on Android 9 and earlier.  */);
+  android_use_exec_loader = true;
+
   /* Functions defined.  */
   defsubr (&Sx_create_frame);
   defsubr (&Sxw_color_defined_p);