Merge "debuggerd: set the name of the signal sender."

#include <errno.h>

#include <signal.h>

#include <stdlib.h>

#include <string.h>

#include <sys/socket.h>

#include <sys/syscall.h>

  int signal;

};

static void set_signal_sender_process_name() {

#if defined(__LP64__)

  static constexpr char long_process_name[] = "debuggerd64:signaller";

  static constexpr char short_process_name[] = "debuggerd64:sig";

  static_assert(sizeof(long_process_name) <= sizeof("/system/bin/debuggerd64"), "");

#else

  static constexpr char long_process_name[] = "debuggerd:signaller";

  static constexpr char short_process_name[] = "debuggerd:sig";

  static_assert(sizeof(long_process_name) <= sizeof("/system/bin/debuggerd"), "");

#endif

  // pthread_setname_np has a maximum length of 16 chars, including null terminator.

  static_assert(sizeof(short_process_name) <= 16, "");

  pthread_setname_np(pthread_self(), short_process_name);

  char* progname = const_cast<char*>(getprogname());

  if (strlen(progname) <= strlen(long_process_name)) {

    ALOGE("debuggerd: unexpected progname %s", progname);

    return;

  }

  memset(progname, 0, strlen(progname));

  strcpy(progname, long_process_name);

}

// Fork a process to send signals for the worker processes to use after they've dropped privileges.

bool start_signal_sender() {

  if (signal_pid != 0) {

  } else if (fork_pid == 0) {

    close(sfd[1]);

    set_signal_sender_process_name();

    while (true) {

      signal_message msg;

      int rc = TEMP_FAILURE_RETRY(read(sfd[0], &msg, sizeof(msg)));