1 /* 2 * Copyright 2013 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkOSFile.h" 9 10 #include "SkTFitsIn.h" 11 12 #include <stdio.h> 13 #include <sys/mman.h> 14 #include <sys/stat.h> 15 #include <sys/types.h> 16 17 typedef struct { 18 dev_t dev; 19 ino_t ino; 20 } SkFILEID; 21 22 static bool sk_ino(SkFILE* a, SkFILEID* id) { 23 int fd = fileno((FILE*)a); 24 if (fd < 0) { 25 return 0; 26 } 27 struct stat status; 28 if (0 != fstat(fd, &status)) { 29 return 0; 30 } 31 id->dev = status.st_dev; 32 id->ino = status.st_ino; 33 return true; 34 } 35 36 bool sk_fidentical(SkFILE* a, SkFILE* b) { 37 SkFILEID aID, bID; 38 return sk_ino(a, &aID) && sk_ino(b, &bID) 39 && aID.ino == bID.ino 40 && aID.dev == bID.dev; 41 } 42 43 void sk_fmunmap(const void* addr, size_t length) { 44 munmap(const_cast<void*>(addr), length); 45 } 46 47 void* sk_fdmmap(int fd, size_t* size) { 48 struct stat status; 49 if (0 != fstat(fd, &status)) { 50 return NULL; 51 } 52 if (!S_ISREG(status.st_mode)) { 53 return NULL; 54 } 55 if (!SkTFitsIn<size_t>(status.st_size)) { 56 return NULL; 57 } 58 size_t fileSize = static_cast<size_t>(status.st_size); 59 60 void* addr = mmap(NULL, fileSize, PROT_READ, MAP_PRIVATE, fd, 0); 61 if (MAP_FAILED == addr) { 62 return NULL; 63 } 64 65 *size = fileSize; 66 return addr; 67 } 68 69 int sk_fileno(SkFILE* f) { 70 return fileno((FILE*)f); 71 } 72 73 void* sk_fmmap(SkFILE* f, size_t* size) { 74 int fd = sk_fileno(f); 75 if (fd < 0) { 76 return NULL; 77 } 78 79 return sk_fdmmap(fd, size); 80 } 81
