diff options
Diffstat (limited to 'Python/fileutils.c')
| -rw-r--r-- | Python/fileutils.c | 48 |
1 files changed, 34 insertions, 14 deletions
diff --git a/Python/fileutils.c b/Python/fileutils.c index a55064ffdc..f5000e533c 100644 --- a/Python/fileutils.c +++ b/Python/fileutils.c @@ -622,10 +622,12 @@ set_inheritable(int fd, int inheritable, int raise, int *atomic_flag_works) #ifdef MS_WINDOWS HANDLE handle; DWORD flags; -#elif defined(HAVE_SYS_IOCTL_H) && defined(FIOCLEX) && defined(FIONCLEX) +#else +#if defined(HAVE_SYS_IOCTL_H) && defined(FIOCLEX) && defined(FIONCLEX) + static int ioctl_works = -1; int request; int err; -#elif defined(HAVE_FCNTL_H) +#endif int flags; int res; #endif @@ -671,20 +673,38 @@ set_inheritable(int fd, int inheritable, int raise, int *atomic_flag_works) } return 0; -#elif defined(HAVE_SYS_IOCTL_H) && defined(FIOCLEX) && defined(FIONCLEX) - if (inheritable) - request = FIONCLEX; - else - request = FIOCLEX; - err = ioctl(fd, request, NULL); - if (err) { - if (raise) - PyErr_SetFromErrno(PyExc_OSError); - return -1; +#else + +#if defined(HAVE_SYS_IOCTL_H) && defined(FIOCLEX) && defined(FIONCLEX) + if (ioctl_works != 0) { + /* fast-path: ioctl() only requires one syscall */ + if (inheritable) + request = FIONCLEX; + else + request = FIOCLEX; + err = ioctl(fd, request, NULL); + if (!err) { + ioctl_works = 1; + return 0; + } + + if (errno != ENOTTY) { + if (raise) + PyErr_SetFromErrno(PyExc_OSError); + return -1; + } + else { + /* Issue #22258: Here, ENOTTY means "Inappropriate ioctl for + device". The ioctl is declared but not supported by the kernel. + Remember that ioctl() doesn't work. It is the case on + Illumos-based OS for example. */ + ioctl_works = 0; + } + /* fallback to fcntl() if ioctl() does not work */ } - return 0; +#endif -#else + /* slow-path: fcntl() requires two syscalls */ flags = fcntl(fd, F_GETFD); if (flags < 0) { if (raise) |