1 #include "SkMMapStream.h" 2 3 #include <unistd.h> 4 #include <sys/mman.h> 5 #include <fcntl.h> 6 #include <errno.h> 7 8 SkMMAPStream::SkMMAPStream(const char filename[]) 9 { 10 fFildes = -1; // initialize to failure case 11 12 int fildes = open(filename, O_RDONLY); 13 if (fildes < 0) 14 { 15 SkDEBUGF(("---- failed to open(%s) for mmap stream error=%d\n", filename, errno)); 16 return; 17 } 18 19 off_t offset = lseek(fildes, 0, SEEK_END); // find the file size 20 if (offset == -1) 21 { 22 SkDEBUGF(("---- failed to lseek(%s) for mmap stream error=%d\n", filename, errno)); 23 close(fildes); 24 return; 25 } 26 (void)lseek(fildes, 0, SEEK_SET); // restore file offset to beginning 27 28 // to avoid a 64bit->32bit warning, I explicitly create a size_t size 29 size_t size = static_cast<size_t>(offset); 30 31 void* addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fildes, 0); 32 if (MAP_FAILED == addr) 33 { 34 SkDEBUGF(("---- failed to mmap(%s) for mmap stream error=%d\n", filename, errno)); 35 close(fildes); 36 return; 37 } 38 39 this->INHERITED::setMemory(addr, size); 40 41 fFildes = fildes; 42 fAddr = addr; 43 fSize = size; 44 } 45 46 SkMMAPStream::~SkMMAPStream() 47 { 48 this->closeMMap(); 49 } 50 51 void SkMMAPStream::setMemory(const void* data, size_t length, bool copyData) 52 { 53 this->closeMMap(); 54 this->INHERITED::setMemory(data, length, copyData); 55 } 56 57 void SkMMAPStream::closeMMap() 58 { 59 if (fFildes >= 0) 60 { 61 munmap(fAddr, fSize); 62 close(fFildes); 63 fFildes = -1; 64 } 65 } 66 67
