Fix Visual Studio compiler warning (strncpy)

Visual Studio complains:
  vdagent\file_xfer.h(28) : warning C4996: 'strncpy': This function or variable may
  Consider using strncpy_s instead.
  To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
  See online help for details.

Replace strncpy with strcpy_s when building with Visual Studio.
Adjust parameter order and difference in meaning of length:
- length param is last in strncpy and second in strcpy_s
- many calls to strncpy are given length param n-1, as
  strncpy does not guarantee that destination ends with '\0'
- it's safer to set length param not larger than sizeof(d)
  (assuming d is an array not a pointer)

Trying to use strcpy_s for both Visual Studio and mingw
failed as strcpy_s is missing from the default msvcrt.dll
on WinXP (See OLDMSVCRT in common/vdcommon.h).

1 files changed, 2 insertions, 0 deletions

diff --git a/vdagent/file_xfer.h b/vdagent/file_xfer.h
index b506f59..07a6808 100644
--- a/vdagent/file_xfer.h
+++ b/vdagent/file_xfer.h
@@ -25,6 +25,8 @@ typedef struct ALIGN_VC FileXferTask {
     FileXferTask(HANDLE _handle, uint64_t _size, char* _name):
     handle(_handle), size(_size), pos(0) {
         // FIXME: should raise an error if name is too long..
+        //        currently the only user is FileXfer::handle_start
+        //        which verifies that strlen(_name) < MAX_PATH
         strncpy(name, _name, sizeof(name) - 1);
     }
     HANDLE handle;