Use GetFileSize correctly on win32

(Use its second parameter to find the high 32 bits of the file size;
check its return value for error conditions.)
This commit is contained in:
Nick Mathewson 2012-05-24 10:19:41 -04:00
parent 75fc4dbbca
commit e7d34935fb
2 changed files with 19 additions and 8 deletions

3
changes/getfilesize_64 Normal file
View File

@ -0,0 +1,3 @@
o Minor bugfixes:
- On Windows, correctly detect errors and large file sizes from
GetFileSize. Fixes bug 5957; bugfix on Tor 0.1.2.1-alpha.

View File

@ -175,6 +175,8 @@ tor_mmap_file(const char *filename)
TCHAR tfilename[MAX_PATH]= {0};
tor_mmap_t *res = tor_malloc_zero(sizeof(tor_mmap_t));
int empty = 0;
DWORD size_low, size_high;
uint64_t real_size;
res->file_handle = INVALID_HANDLE_VALUE;
res->mmap_handle = NULL;
#ifdef UNICODE
@ -192,23 +194,29 @@ tor_mmap_file(const char *filename)
if (res->file_handle == INVALID_HANDLE_VALUE)
goto win_err;
res->size = GetFileSize(res->file_handle, NULL);
size_low = GetFileSize(res->file_handle, &size_high);
if (res->size == 0) {
if (size_low == INVALID_FILE_SIZE && GetLastError() != NO_ERROR) {
log_warn(LD_FS,"Error getting size of \"%s\".",filename);
goto win_err;
}
if (size_low == 0 && size_high == 0) {
log_info(LD_FS,"File \"%s\" is empty. Ignoring.",filename);
empty = 1;
goto err;
}
real_size = (((uint64_t)size_high)<<32) | size_low;
if (real_size > SIZE_MAX) {
log_warn(LD_FS,"File \"%s\" is too big to map; not trying.",filename);
goto err;
}
res->size = real_size;
res->mmap_handle = CreateFileMapping(res->file_handle,
NULL,
PAGE_READONLY,
#if SIZEOF_SIZE_T > 4
(res->base.size >> 32),
#else
0,
#endif
(res->size & 0xfffffffful),
size_high,
size_low,
NULL);
if (res->mmap_handle == NULL)
goto win_err;