1 files changed, 141 insertions, 0 deletions
diff --git a/src/utilcode/makepath.cpp b/src/utilcode/makepath.cpp
index 3d948d53a1..37b7202dba 100644
--- a/src/utilcode/makepath.cpp
+++ b/src/utilcode/makepath.cpp
@@ -15,6 +15,7 @@
 #include "utilcode.h"
 #include "ex.h"
 
+#ifndef FEATURE_CORECLR
 /***
 *void _makepath() - build path name from components
 *
@@ -165,6 +166,146 @@ void MakePath (
                 *path = _T('\0');
         }
 }
+#endif // !FEATURE_CORECLR
+
+/***
+*void Makepath() - build path name from components
+*
+*Purpose:
+*       create a path name from its individual components
+*
+*Entry:
+*       CQuickWSTR &szPath - Buffer for constructed path
+*       WCHAR *drive - pointer to drive component, may or may not contain
+*                     trailing ':'
+*       WCHAR *dir   - pointer to subdirectory component, may or may not include
+*                     leading and/or trailing '/' or '\' characters
+*       WCHAR *fname - pointer to file base name component
+*       WCHAR *ext   - pointer to extension component, may or may not contain
+*                     a leading '.'.
+*
+*Exit:
+*       path - pointer to constructed path name
+*
+*Exceptions:
+*
+*******************************************************************************/
+
+void MakePath (
+        __out CQuickWSTR &szPath,
+        __in LPCWSTR drive,
+        __in LPCWSTR dir,
+        __in LPCWSTR fname,
+        __in LPCWSTR ext
+        )
+{
+        CONTRACTL
+        {
+            NOTHROW;
+            GC_NOTRIGGER;
+        }
+        CONTRACTL_END
+
+        SIZE_T maxCount = 4      // Possible separators between components, plus null terminator
+            + (drive != nullptr ? 2 : 0)
+            + (dir != nullptr ? wcslen(dir) : 0)
+            + (fname != nullptr ? wcslen(fname) : 0)
+            + (ext != nullptr ? wcslen(ext) : 0);
+        LPWSTR path = szPath.AllocNoThrow(maxCount);
+
+        const WCHAR *p;
+        DWORD count = 0;
+
+        /* we assume that the arguments are in the following form (although we
+         * do not diagnose invalid arguments or illegal filenames (such as
+         * names longer than 8.3 or with illegal characters in them)
+         *
+         *  drive:
+         *      A           ; or
+         *      A:
+         *  dir:
+         *      \top\next\last\     ; or
+         *      /top/next/last/     ; or
+         *      either of the above forms with either/both the leading
+         *      and trailing / or \ removed.  Mixed use of '/' and '\' is
+         *      also tolerated
+         *  fname:
+         *      any valid file name
+         *  ext:
+         *      any valid extension (none if empty or null )
+         */
+
+        /* copy drive */
+
+        if (drive && *drive) {
+                *path++ = *drive;
+                *path++ = _T(':');
+                count += 2;
+        }
+
+        /* copy dir */
+
+        if ((p = dir)) {
+                while (*p) {
+                        *path++ = *p++;
+                        count++;
+
+                        _ASSERTE(count < maxCount);
+                }
+
+#ifdef _MBCS
+                if (*(p=_mbsdec(dir,p)) != _T('/') && *p != _T('\\')) {
+#else  /* _MBCS */
+                // suppress warning for the following line; this is safe but would require significant code
+                // delta for prefast to understand.
+#ifdef _PREFAST_
+                #pragma warning( suppress: 26001 ) 
+#endif
+                if (*(p-1) != _T('/') && *(p-1) != _T('\\')) {
+#endif  /* _MBCS */
+                        *path++ = _T('\\');
+                        count++;
+
+                        _ASSERTE(count < maxCount);
+                }
+        }
+
+        /* copy fname */
+
+        if ((p = fname)) {
+                while (*p) {
+                        *path++ = *p++;
+                        count++;
+
+                        _ASSERTE(count < maxCount);
+                }
+        }
+
+        /* copy ext, including 0-terminator - check to see if a '.' needs
+         * to be inserted.
+         */
+
+        if ((p = ext)) {
+                if (*p && *p != _T('.')) {
+                        *path++ = _T('.');
+                        count++;
+
+                        _ASSERTE(count < maxCount);
+                }
+
+                while ((*path++ = *p++)) {
+                    count++;
+
+                    _ASSERTE(count < maxCount);
+                }
+        }
+        else {
+                /* better add the 0-terminator */
+                *path = _T('\0');
+        }
+
+        szPath.Shrink(count + 1);
+}
 
 #if !defined(FEATURE_CORECLR)
 static LPCWSTR g_wszProcessExePath = NULL;