src/stream.c

   1 #include "first.h"
   2
   3 #include "stream.h"
   4
   5 #include <sys/types.h>
   6 #include <sys/stat.h>
   7
   8 #include <unistd.h>
   9 #include <fcntl.h>
  10
  11 #include "sys-mmap.h"
  12
  13 #ifndef O_BINARY
  14 # define O_BINARY 0
  15 #endif
  16
  17 /* don't want to block when open()ing a fifo */
  18 #if defined(O_NONBLOCK)
  19 # define FIFO_NONBLOCK O_NONBLOCK
  20 #else
  21 # define FIFO_NONBLOCK 0
  22 #endif
  23
  24 int stream_open(stream *f, buffer *fn) {
  25
  26 #ifdef HAVE_MMAP
  27
  28         struct stat st;
  29         int fd;
  30
  31         f->start = NULL;
  32         f->size = 0;
  33
  34         if (-1 == (fd = open(fn->ptr, O_RDONLY | O_BINARY | FIFO_NONBLOCK))) {
  35                 return -1;
  36         }
  37
  38         if (-1 == fstat(fd, &st)) {
  39                 close(fd);
  40                 return -1;
  41         }
  42
  43         if (0 == st.st_size) {
  44                 /* empty file doesn't need a mapping */
  45                 close(fd);
  46                 return 0;
  47         }
  48
  49         f->start = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
  50
  51         close(fd);
  52
  53         if (MAP_FAILED == f->start) {
  54                 f->start = NULL;
  55                 return -1;
  56         }
  57
  58         f->size = st.st_size;
  59         return 0;
  60
  61 #elif defined __WIN32
  62
  63         HANDLE *fh, *mh;
  64         void *p;
  65         LARGE_INTEGER fsize;
  66
  67         f->start = NULL;
  68         f->size = 0;
  69
  70         fh = CreateFile(fn->ptr,
  71                         GENERIC_READ,
  72                         FILE_SHARE_READ,
  73                         NULL,
  74                         OPEN_EXISTING,
  75                         FILE_ATTRIBUTE_READONLY,
  76                         NULL);
  77
  78         if (!fh) return -1;
  79
  80         if (0 != GetFileSizeEx(fh, &fsize)) {
  81                 CloseHandle(fh);
  82                 return -1;
  83         }
  84
  85         if (0 == fsize) {
  86                 CloseHandle(fh);
  87                 return 0;
  88         }
  89
  90         mh = CreateFileMapping( fh,
  91                         NULL,
  92                         PAGE_READONLY,
  93                         (sizeof(off_t) > 4) ? fsize >> 32 : 0,
  94                         fsize & 0xffffffff,
  95                         NULL);
  96
  97         if (!mh) {
  98 /*
  99                 LPVOID lpMsgBuf;
 100                 FormatMessage(
 101                         FORMAT_MESSAGE_ALLOCATE_BUFFER |
 102                         FORMAT_MESSAGE_FROM_SYSTEM,
 103                         NULL,
 104                         GetLastError(),
 105                         MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
 106                         (LPTSTR) &lpMsgBuf,
 107                         0, NULL );
 108 */
 109                 CloseHandle(fh);
 110                 return -1;
 111         }
 112
 113         p = MapViewOfFile(mh,
 114                         FILE_MAP_READ,
 115                         0,
 116                         0,
 117                         0);
 118         CloseHandle(mh);
 119         CloseHandle(fh);
 120
 121         f->start = p;
 122         f->size = (off_t)fsize;
 123         return 0;
 124
 125 #else
 126 # error no mmap found
 127 #endif
 128
 129 }
 130
 131 int stream_close(stream *f) {
 132 #ifdef HAVE_MMAP
 133         if (f->start) munmap(f->start, f->size);
 134 #elif defined(__WIN32)
 135         if (f->start) UnmapViewOfFile(f->start);
 136 #endif
 137
 138         f->start = NULL;
 139         f->size = 0;
 140
 141         return 0;
 142 }