Andrew's git / gitweb.git /
b836169b3ce88d2967b52fa4e3a697f895dc1a13
   1#include "../git-compat-util.h"
   2
   3void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
   4{
   5        HANDLE hmap;
   6        void *temp;
   7        off_t len;
   8        struct stat st;
   9        uint64_t o = offset;
  10        uint32_t l = o & 0xFFFFFFFF;
  11        uint32_t h = (o >> 32) & 0xFFFFFFFF;
  12
  13        if (!fstat(fd, &st))
  14                len = st.st_size;
  15        else
  16                die("mmap: could not determine filesize");
  17
  18        if ((length + offset) > len)
  19                length = xsize_t(len - offset);
  20
  21        if (!(flags & MAP_PRIVATE))
  22                die("Invalid usage of mmap when built with USE_WIN32_MMAP");
  23
  24        hmap = CreateFileMapping((HANDLE)_get_osfhandle(fd), NULL,
  25                prot == PROT_READ ? PAGE_READONLY : PAGE_WRITECOPY, 0, 0, NULL);
  26
  27        if (!hmap) {
  28                errno = EINVAL;
  29                return MAP_FAILED;
  30        }
  31
  32        temp = MapViewOfFileEx(hmap, prot == PROT_READ ?
  33                        FILE_MAP_READ : FILE_MAP_COPY, h, l, length, start);
  34
  35        if (!CloseHandle(hmap))
  36                warning("unable to close file mapping handle");
  37
  38        if (temp)
  39                return temp;
  40
  41        errno = GetLastError() == ERROR_COMMITMENT_LIMIT ? EFBIG : EINVAL;
  42        return MAP_FAILED;
  43}
  44
  45int git_munmap(void *start, size_t length)
  46{
  47        return !UnmapViewOfFile(start);
  48}