[1/2] shell32: fix CommandLineToArgvW("") truncating returned exe path.

[Ilya Basin]

This fixes http://bugs.winehq.org/show_bug.cgi?id=21758
Currently CommandLineToArgvW("") returns only the first 6 characters
of the exe path. And even worse, it doesn't terminate the result
string with 0, which can potentially cause access violations.

Here's the crosstest output:
[il at IL wine-git]$ ./wine dlls/shell32/tests/shell32_crosstest.exe shlexec
...
shlexec.c:2182: Test failed: wrong path to the current executable
  expected: L"Z:\\home\\il\\builds\\wine-git\\dlls\\shell32\\tests\\shell32_crosstest.exe"
  got     : L"Z:\\homCe\64d0\0013("
shlexec: 411 tests executed (0 marked as todo, 21 failures), 0 skipped.

---
 dlls/shell32/shell32_main.c |   12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/dlls/shell32/shell32_main.c b/dlls/shell32/shell32_main.c
index 2824268..4fb0863 100644
--- a/dlls/shell32/shell32_main.c
+++ b/dlls/shell32/shell32_main.c
@@ -93,20 +93,22 @@ LPWSTR* WINAPI CommandLineToArgvW(LPCWSTR lpCmdline, int* numargs)
     if (*lpCmdline==0)
     {
         /* Return the path to the executable */
-        DWORD len, size=16;
+        DWORD len, deslen=MAX_PATH, size;
 
+        size = sizeof(LPWSTR) + deslen*sizeof(WCHAR) + sizeof(LPWSTR);
         argv=LocalAlloc(LMEM_FIXED, size);
         for (;;)
         {
-            len = GetModuleFileNameW(0, (LPWSTR)(argv+1), (size-sizeof(LPWSTR))/sizeof(WCHAR));
+            len = GetModuleFileNameW(0, (LPWSTR)(argv+1), deslen);
             if (!len)
             {
                 LocalFree(argv);
                 return NULL;
             }
-            if (len < size) break;
-            size*=2;
-            argv=LocalReAlloc(argv, size, 0);
+            if (len < deslen) break;
+            deslen*=2;
+            size = sizeof(LPWSTR) + deslen*sizeof(WCHAR) + sizeof(LPWSTR);
+            argv=LocalReAlloc(argv, size, LMEM_MOVEABLE);
         }
         argv[0]=(LPWSTR)(argv+1);
         if (numargs)
-- 
1.7.1.1