1 #include "SkMMapStream.h"
2
3 #include <unistd.h>
4 #include <sys/mman.h>
5 #include <fcntl.h>
6 #include <errno.h>
7
SkMMAPStream(const char filename[])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
~SkMMAPStream()46 SkMMAPStream::~SkMMAPStream()
47 {
48 this->closeMMap();
49 }
50
setMemory(const void * data,size_t length,bool copyData)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
closeMMap()57 void SkMMAPStream::closeMMap()
58 {
59 if (fFildes >= 0)
60 {
61 munmap(fAddr, fSize);
62 close(fFildes);
63 fFildes = -1;
64 }
65 }
66
67