1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <errno.h> 30 #include <fcntl.h> 31 #include <stdarg.h> 32 #include <sys/resource.h> 33 #include <sys/types.h> 34 #include <sys/vfs.h> 35 #include <unistd.h> 36 37 #if __LP64__ 38 #error This code is only needed on 32-bit systems! 39 #endif 40 41 // System calls we need. 42 extern "C" int __fcntl64(int, int, void*); 43 extern "C" int __fstatfs64(int, size_t, struct statfs*); 44 extern "C" int __llseek(int, unsigned long, unsigned long, off64_t*, int); 45 extern "C" int __statfs64(const char*, size_t, struct statfs*); 46 47 // For fcntl we use the fcntl64 system call to signal that we're using struct flock64. 48 int fcntl(int fd, int cmd, ...) { 49 va_list ap; 50 51 va_start(ap, cmd); 52 void* arg = va_arg(ap, void*); 53 va_end(ap); 54 55 return __fcntl64(fd, cmd, arg); 56 } 57 58 // For fstatfs we need to add the extra argument giving the kernel the size of the buffer. 59 int fstatfs(int fd, struct statfs* stat) { 60 return __fstatfs64(fd, sizeof(*stat), stat); 61 } 62 __strong_alias(fstatfs64, fstatfs); 63 64 // For statfs we need to add the extra argument giving the kernel the size of the buffer. 65 int statfs(const char* path, struct statfs* stat) { 66 return __statfs64(path, sizeof(*stat), stat); 67 } 68 __strong_alias(statfs64, statfs); 69 70 // For lseek64 we need to use the llseek system call which splits the off64_t in two and 71 // returns the off64_t result via a pointer because 32-bit kernels can't return 64-bit results. 72 off64_t lseek64(int fd, off64_t off, int whence) { 73 off64_t result; 74 unsigned long off_hi = static_cast<unsigned long>(off >> 32); 75 unsigned long off_lo = static_cast<unsigned long>(off); 76 if (__llseek(fd, off_hi, off_lo, &result, whence) < 0) { 77 return -1; 78 } 79 return result; 80 } 81 82 // There is no pread for 32-bit off_t, so we need to widen and call pread64. 83 ssize_t pread(int fd, void* buf, size_t byte_count, off_t offset) { 84 return pread64(fd, buf, byte_count, static_cast<off64_t>(offset)); 85 } 86 87 // There is no pwrite for 32-bit off_t, so we need to widen and call pwrite64. 88 ssize_t pwrite(int fd, const void* buf, size_t byte_count, off_t offset) { 89 return pwrite64(fd, buf, byte_count, static_cast<off64_t>(offset)); 90 } 91 92 // There is no fallocate for 32-bit off_t, so we need to widen and call fallocate64. 93 int fallocate(int fd, int mode, off_t offset, off_t length) { 94 return fallocate64(fd, mode, static_cast<off64_t>(offset), static_cast<off64_t>(length)); 95 } 96 97 // There is no getrlimit64 system call, so we need to use prlimit64. 98 int getrlimit64(int resource, rlimit64* limits64) { 99 return prlimit64(0, resource, NULL, limits64); 100 } 101 102 // There is no setrlimit64 system call, so we need to use prlimit64. 103 int setrlimit64(int resource, const rlimit64* limits64) { 104 return prlimit64(0, resource, limits64, NULL); 105 } 106
