multiple errors when compiling libfutex

[iamalsaher]

[arm64-v8a] Compile        : futex_exploit <= futex.c
libfutex_exploit/futex.c:33:5: error: non-void function 'create_server_socket' should return a value [-Wreturn-type]
    return;
    ^
libfutex_exploit/futex.c:46:5: warning: implicit declaration of function 'close' is invalid in C99 [-Wimplicit-function-declaration]
    close(sockfd);
    ^
libfutex_exploit/futex.c:152:9: warning: implicit declaration of function 'fork' is invalid in C99 [-Wimplicit-function-declaration]
  pid = fork();
        ^
libfutex_exploit/futex.c:158:7: warning: implicit declaration of function 'futex_exploit_main' is invalid in C99 [-Wimplicit-function-declaration]
  if (futex_exploit_main()) {
      ^
libfutex_exploit/futex.c:188:7: warning: implicit declaration of function 'write' is invalid in C99 [-Wimplicit-function-declaration]
  if (write(sockfd, req, sizeof (*req)) != sizeof (*req)) {
      ^
libfutex_exploit/futex.c:198:7: warning: implicit declaration of function 'read' is invalid in C99 [-Wimplicit-function-declaration]
  if (read(sockfd, req, sizeof (*req)) != sizeof (*req)) {
      ^
5 warnings and 1 error generated.
make: *** [obj/local/arm64-v8a/objs/futex_exploit/futex.o] Error 1

And since I don't know what it should return, I just set it to false, and then this occurs

[arm64-v8a] Compile        : futex_exploit <= exploit.c
libfutex_exploit/exploit.c:82:8: error: redefinition of 'mmsghdr'
struct mmsghdr {
       ^
/root/Android/Sdk/ndk-bundle/platforms/android-21/arch-arm64/usr/include/sys/socket.h:99:8: note: previous definition is here
struct mmsghdr {
       ^
libfutex_exploit/exploit.c:114:17: warning: type specifier missing, defaults to 'int' [-Wimplicit-int]
static volatile int_sync_time_out = 0;
~~~~~~~~~~~~~~~ ^
libfutex_exploit/exploit.c:221:15: error: assigning to 'sigset_t' from incompatible type 'int'
  act.sa_mask = 0;
              ^ ~
libfutex_exploit/exploit.c:290:15: error: assigning to 'sigset_t' from incompatible type 'int'
  act.sa_mask = 0;
              ^ ~
libfutex_exploit/exploit.c:317:61: warning: cast to 'void *' from smaller integer type 'int' [-Wint-to-void-pointer-cast]
  pthread_create(&th4, 0, call_futex_lock_pi_with_priority, (void *)prio);
                                                            ^
2 warnings and 3 errors generated.
make: *** [obj/local/arm64-v8a/objs/futex_exploit/exploit.o] Error 1

Please help me out
Please specify as to what it should return and how to resolve this

[dadreamer]

For create_server_socket you should alter the return to be return true (not false).
For sigset_t change zero assignment of a variable to sigemptyset call.
For mmsghdr please look at this thread.

You just started digging those errors. There are more to come up. :)