suid flag for su binary in Android

Question

Which script of the android build tree is giving the "suid" flag to the su binary before the system.img file is packed? I've "grepped" for "chmod +s" or "chmod 4" strings but no luck for now.

Answer 1

Found the solution. The file I was searching for is :

system/core/include/private/android_filesystem_config.h

Suid binaries are defined in the "android_files" structure. For the su binary there is this entry:

{ 06755, AID_ROOT, AID_ROOT, "system/xbin/su" },