PthreadKeyDetect is a tool to detect the available number of Android pthread_key and hook pthread_key-related functions.
In Android devices, every pthread_key_create function invoked will cost one pthread_key_t key, there is a limit of PTHREAD_KEYS_MAX(128 or 64) keys per process. The compiler will automatically use ELF TLS (minSdkVersion >= 29, see Android linker changes for NDK developers), but many Apps use minSdkVersion <29. So, there may be unpredictable crashes if your App costs more than the PTHREAD_KEYS_MAX keys in one process. The most common keywords in the crash stack are: pthread_once、emutls_get_address、cxa_get_globals、emutls_init.
Therefore, this tool is to help troubleshoot the problem of the number of pthread_key used.
The main features are:
- Get the maximum pthread_key_t count(
PTHREAD_KEYS_MAX) that the device supports. - Get the maximum pthread_key_t count that the app's current process can be created in the current status.
- Hook
pthread_key_createandpthread_key_deletefunctions call, Non-invasive. Hook It is based on Tencent/matrix.
The library only has one class PthreadKeyDetect
hook()hook native 'pthread_key_delete' and 'pthread_key_delete' functions, you can find who use pthread_key_t.available()the maximum pthread_can_t count that the app's current process can be created in the current status.max()returns the maximum pthread_key_t count that the device supports creating.useUp()use up all pthread_key_t, can test extreme cases, how your app works
This library only run in the test environment, don't use it in the product environment, there may be unexpected errors.