From: Anders Björklund <anders@itension.se>
Date: Fri, 4 Mar 2016 14:22:59 +0000 (+0100)
Subject: Add compat version of GetFinalPathNameByHandle
X-Git-Tag: v3.3~100
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a21da6fff6e7f796c42b1a6f784d42945395025b;p=thirdparty%2Fccache.git

Add compat version of GetFinalPathNameByHandle
---

diff --git a/configure.ac b/configure.ac
index af56dca60..988ac315f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -123,6 +123,7 @@ fi
 dnl Linking on Windows needs ws2_32
 if test x${windows_os} = xyes; then
     LIBS="$LIBS -lws2_32"
+    AC_CHECK_FUNCS(GetFinalPathNameByHandleW,[],[LIBS="$LIBS -lpsapi"])
 fi
 
 AC_C_BIGENDIAN
diff --git a/util.c b/util.c
index 73fb4d5a0..b0d4491a8 100644
--- a/util.c
+++ b/util.c
@@ -31,6 +31,8 @@
 #ifdef _WIN32
 #include <windows.h>
 #include <sys/locking.h>
+#include <psapi.h>
+#include <tchar.h>
 #endif
 
 static FILE *logfile;
@@ -1078,6 +1080,93 @@ parse_size_with_suffix(const char *str, uint64_t *size)
 }
 
 
+#if defined(_WIN32) && !defined(HAVE_GETFINALPATHNAMEBYHANDLEW)
+static BOOL GetFileNameFromHandle(HANDLE hFile, TCHAR *pszFilename,
+                                  WORD cchFilename)
+{
+	BOOL bSuccess = FALSE;
+	HANDLE hFileMap;
+
+	// Get the file size.
+	DWORD dwFileSizeHi = 0;
+	DWORD dwFileSizeLo = GetFileSize(hFile, &dwFileSizeHi);
+
+	if (dwFileSizeLo == 0 && dwFileSizeHi == 0) {
+		// Cannot map a file with a length of zero.
+		return FALSE;
+	}
+
+	// Create a file mapping object.
+	hFileMap = CreateFileMapping(hFile,
+	                             NULL,
+	                             PAGE_READONLY,
+	                             0,
+	                             1,
+	                             NULL);
+
+	if (hFileMap) {
+		// Create a file mapping to get the file name.
+		void *pMem = MapViewOfFile(hFileMap, FILE_MAP_READ, 0, 0, 1);
+
+		if (pMem) {
+			if (GetMappedFileName(GetCurrentProcess(),
+			                      pMem,
+			                      pszFilename,
+			                      cchFilename)) {
+
+				// Translate path with device name to drive letters.
+				TCHAR szTemp[512];
+				szTemp[0] = '\0';
+
+				if (GetLogicalDriveStrings(512-1, szTemp)) {
+					TCHAR szName[MAX_PATH];
+					TCHAR szDrive[3] = TEXT(" :");
+					BOOL bFound = FALSE;
+					TCHAR *p = szTemp;
+
+					do
+					{
+						// Copy the drive letter to the template string
+						*szDrive = *p;
+
+						// Look up each device name
+						if (QueryDosDevice(szDrive, szName, MAX_PATH)) {
+							size_t uNameLen = _tcslen(szName);
+
+							if (uNameLen < MAX_PATH) {
+								bFound = _tcsnicmp(pszFilename, szName, uNameLen) == 0
+								         && *(pszFilename + uNameLen) == _T('\\');
+
+								if (bFound) {
+									// Reconstruct pszFilename using szTempFile
+									// Replace device path with DOS path
+									TCHAR szTempFile[MAX_PATH];
+									_sntprintf(szTempFile,
+									           MAX_PATH-1,
+									           TEXT("%s%s"),
+									           szDrive,
+									           pszFilename+uNameLen);
+									_tcsncpy(pszFilename, szTempFile,
+									         _tcslen(szTempFile));
+								}
+							}
+						}
+
+						// Go to the next NULL character.
+						while (*p++) ;
+					} while (!bFound && *p); // end of string
+				}
+			}
+			bSuccess = TRUE;
+			UnmapViewOfFile(pMem);
+		}
+
+		CloseHandle(hFileMap);
+	}
+	return(bSuccess);
+}
+#endif
+
 /* A sane realpath() function, trying to cope with stupid path limits and a
  * broken API. Caller frees. */
 char *
@@ -1100,7 +1189,11 @@ x_realpath(const char *path)
 	  path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING,
 	  FILE_ATTRIBUTE_NORMAL, NULL);
 	if (INVALID_HANDLE_VALUE != path_handle) {
+#ifdef HAVE_GETFINALPATHNAMEBYHANDLEW
 		GetFinalPathNameByHandle(path_handle, ret, maxlen, FILE_NAME_NORMALIZED);
+#else
+		GetFileNameFromHandle(path_handle, ret, maxlen);
+#endif
 		CloseHandle(path_handle);
 		p = ret + 4; /* strip \\?\ from the file name */
 	} else {