60 lines · cpp
1// RUN: %clangxx -O0 -g %s -lutil -o %t && %run %t2// This test depends on the glibc layout of struct sem_t and checks that we3// don't leave sem_t::private uninitialized.4// UNSUPPORTED: android, lsan-x86, ubsan5#include <features.h>6#include <assert.h>7#include <semaphore.h>8#include <string.h>9#include <stdint.h>10 11// musl and glibc's __HAVE_64B_ATOMICS==0 ports (e.g. arm, i386) use 32-bit sem12// values. 64-bit glibc ports defining sem_init@GLIBC_2.0 (mips64) use 32-bit as13// well, if the sem_init interceptor picks the oldest versioned symbol14// (glibc<2.36, see https://sourceware.org/PR14932).15#if !defined(__GLIBC__) || defined(__ILP32__) || \16 !__GLIBC_PREREQ(2, 36) && defined(__mips64__)17typedef unsigned semval_t;18#else19typedef uint64_t semval_t;20#endif21 22// glibc __HAVE_64B_ATOMICS==0 ports define a sem_init which shifts the value by23// 1 (https://sourceware.org/PR12674 glibc 2.21). The version is picked if24// either glibc>=2.36 or sem_init@GLIBC_2.0 is absent (arm and newer ports).25//26// The __GLIBC_PREREQ check is brittle in that it requires matched27// __GLIBC_PREREQ values for build time and run time.28#if defined(__GLIBC__) && defined(__ILP32__) && \29 (__GLIBC_PREREQ(2, 36) || (__GLIBC_PREREQ(2, 21) && !defined(__i386__) && \30 !defined(__mips__) && !defined(__powerpc__)))31# define GET_SEM_VALUE(V) ((V) >> 1)32#else33# define GET_SEM_VALUE(V) (V)34#endif35 36void my_sem_init(bool priv, int value, semval_t *a, unsigned char *b) {37 sem_t sem;38 memset(&sem, 0xAB, sizeof(sem));39 sem_init(&sem, priv, value);40 41 char *p = (char *)&sem;42 memcpy(a, p, sizeof(semval_t));43 memcpy(b, p + sizeof(semval_t), sizeof(char));44 45 sem_destroy(&sem);46}47 48int main() {49 semval_t a;50 unsigned char b;51 52 my_sem_init(false, 42, &a, &b);53 assert(GET_SEM_VALUE(a) == 42);54 assert(b != 0xAB);55 56 my_sem_init(true, 43, &a, &b);57 assert(GET_SEM_VALUE(a) == 43);58 assert(b != 0xAB);59}60