Merge "libcutils: sdk(mac) build error" am: 231d1ac6 am: 7bc8810a

#include "android_get_control_env.h"

#ifndef TEMP_FAILURE_RETRY

#define TEMP_FAILURE_RETRY(exp) (exp) // KISS implementation

#endif

LIBCUTILS_HIDDEN int __android_get_control_from_env(const char* prefix,

                                                    const char* name) {

    if (!prefix || !name) return -1;

    // Since we are inheriting an fd, it could legitimately exceed _SC_OPEN_MAX

    // Still open?

#if defined(F_GETFD) // Linux lowest overhead

#if defined(F_GETFD) // Lowest overhead

    if (TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD)) < 0) return -1;

#elif defined(F_GETFL) // Mac host lowest overhead

    if (fcntl(fd, F_GETFL) < 0) return -1;

#elif defined(F_GETFL) // Alternate lowest overhead

    if (TEMP_FAILURE_RETRY(fcntl(fd, F_GETFL)) < 0) return -1;

#else // Hail Mary pass

    struct stat s;

    if (fstat(fd, &s) < 0) return -1;

    if (TEMP_FAILURE_RETRY(fstat(fd, &s)) < 0) return -1;

#endif

    return static_cast<int>(fd);