source: asp3_tinet_ecnl_arm/trunk/musl-1.1.18/src/fcntl/fcntl.c@ 352

#define _GNU_SOURCE
#include <fcntl.h>
#include <stdarg.h>
#include <errno.h>
#include "syscall.h"
#include "libc.h"

int fcntl(int fd, int cmd, ...)
{
        unsigned long arg;
        va_list ap;
        va_start(ap, cmd);
        arg = va_arg(ap, unsigned long);
        va_end(ap);
        if (cmd == F_SETFL) arg |= O_LARGEFILE;
        if (cmd == F_SETLKW) return syscall_cp(SYS_fcntl, fd, cmd, (void *)arg);
        if (cmd == F_GETOWN) {
                struct f_owner_ex ex;
                int ret = __syscall(SYS_fcntl, fd, F_GETOWN_EX, &ex);
                if (ret == -EINVAL) return __syscall(SYS_fcntl, fd, cmd, (void *)arg);
                if (ret) return __syscall_ret(ret);
                return ex.type == F_OWNER_PGRP ? -ex.pid : ex.pid;
        }
        if (cmd == F_DUPFD_CLOEXEC) {
                int ret = __syscall(SYS_fcntl, fd, F_DUPFD_CLOEXEC, arg);
                if (ret != -EINVAL) {
                        if (ret >= 0)
                                __syscall(SYS_fcntl, ret, F_SETFD, FD_CLOEXEC);
                        return __syscall_ret(ret);
                }
                ret = __syscall(SYS_fcntl, fd, F_DUPFD_CLOEXEC, 0);
                if (ret != -EINVAL) {
                        if (ret >= 0) __syscall(SYS_close, ret);
                        return __syscall_ret(-EINVAL);
                }
                ret = __syscall(SYS_fcntl, fd, F_DUPFD, arg);
                if (ret >= 0) __syscall(SYS_fcntl, ret, F_SETFD, FD_CLOEXEC);
                return __syscall_ret(ret);
        }
        switch (cmd) {
        case F_SETLK:
        case F_GETLK:
        case F_GETOWN_EX:
        case F_SETOWN_EX:
                return syscall(SYS_fcntl, fd, cmd, (void *)arg);
        default:
                return syscall(SYS_fcntl, fd, cmd, arg);
        }
}