| 1 | //===-- Linux implementation of ftruncate ---------------------------------===// |
|---|
| 2 | // |
|---|
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
|---|
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
|---|
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
|---|
| 6 | // |
|---|
| 7 | //===----------------------------------------------------------------------===// |
|---|
| 8 | |
|---|
| 9 | #include "src/unistd/ftruncate.h" |
|---|
| 10 | |
|---|
| 11 | #include "src/__support/OSUtil/syscall.h" // For internal syscall function. |
|---|
| 12 | #include "src/__support/common.h" |
|---|
| 13 | |
|---|
| 14 | #include "hdr/unistd_macros.h" |
|---|
| 15 | #include "src/__support/libc_errno.h" |
|---|
| 16 | #include "src/__support/macros/config.h" |
|---|
| 17 | #include <stdint.h> // For uint64_t. |
|---|
| 18 | #include <sys/syscall.h> // For syscall numbers. |
|---|
| 19 | |
|---|
| 20 | namespace LIBC_NAMESPACE_DECL { |
|---|
| 21 | |
|---|
| 22 | LLVM_LIBC_FUNCTION(int, ftruncate, (int fd, off_t len)) { |
|---|
| 23 | #ifdef SYS_ftruncate |
|---|
| 24 | int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_ftruncate, fd, len); |
|---|
| 25 | #elif defined(SYS_ftruncate64) |
|---|
| 26 | // Same as ftruncate but can handle large offsets |
|---|
| 27 | static_assert(sizeof(off_t) == 8); |
|---|
| 28 | int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_ftruncate64, fd, (long)len, |
|---|
| 29 | (long)(((uint64_t)(len)) >> 32)); |
|---|
| 30 | #else |
|---|
| 31 | #error "ftruncate and ftruncate64 syscalls not available." |
|---|
| 32 | #endif |
|---|
| 33 | |
|---|
| 34 | if (ret < 0) { |
|---|
| 35 | libc_errno = -ret; |
|---|
| 36 | return -1; |
|---|
| 37 | } |
|---|
| 38 | return 0; |
|---|
| 39 | } |
|---|
| 40 | |
|---|
| 41 | } // namespace LIBC_NAMESPACE_DECL |
|---|
| 42 | |
|---|
