Improve error logging in win32 emu library.

Consistently capture the last Windows error code in the global variable
winerrno. Add logging macros that report the Windows error message for
this error code.

1 files changed, 76 insertions, 48 deletions

diff --git a/lib/win32/emu.cpp b/lib/win32/emu.cpp
index ee1f461a..f7cf7693 100644
--- a/lib/win32/emu.cpp
+++ b/lib/win32/emu.cpp
@@ -32,8 +32,9 @@ bool EnableBackupRights()
 	if(!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, 
 		&hToken))
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to open process token: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return false;
 	}
 
@@ -45,8 +46,9 @@ bool EnableBackupRights()
 		SE_BACKUP_NAME, //the name of the privilege
 		&( token_priv.Privileges[0].Luid ))) //result
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to lookup backup privilege: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		CloseHandle(hToken);
 		return false;
 	}
@@ -68,8 +70,9 @@ bool EnableBackupRights()
 		//this function is a little tricky - if we were adjusting
 		//more than one privilege, it could return success but not
 		//adjust them all - in the general case, you need to trap this
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to enable backup privilege: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		CloseHandle(hToken);
 		return false;
 
@@ -238,9 +241,10 @@ char* ConvertFromWideString(const WCHAR* pString, unsigned int codepage)
 
 	if (len == 0)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, 
 			"Failed to convert wide string to narrow: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EINVAL;
 		return NULL;
 	}
@@ -270,9 +274,10 @@ char* ConvertFromWideString(const WCHAR* pString, unsigned int codepage)
 
 	if (len == 0)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, 
 			"Failed to convert wide string to narrow: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		delete [] buffer;
 		return NULL;
@@ -299,9 +304,10 @@ bool ConvertFromWideString(const std::wstring& rInput,
 
 	if (len == 0)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, 
 			"Failed to convert wide string to narrow: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EINVAL;
 		return false;
 	}
@@ -331,9 +337,10 @@ bool ConvertFromWideString(const std::wstring& rInput,
 
 	if (len == 0)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, 
 			"Failed to convert wide string to narrow: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		delete [] buffer;
 		return false;
@@ -363,10 +370,11 @@ bool ConvertEncoding(const std::string& rSource, int sourceCodePage,
 		true);
 	if (pWide == NULL)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to convert string '%s' from "
 			"current code page %d to wide string: %s",
 			rSource.c_str(), sourceCodePage,
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return false;
 	}
 
@@ -641,7 +649,7 @@ HANDLE openfile(const char *pFileName, int flags, int mode)
 
 		::syslog(LOG_WARNING, "Failed to open file '%s': "
 			"%s", pFileName, 
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 
 		return INVALID_HANDLE_VALUE;
 	}
@@ -684,16 +692,18 @@ int emu_fstat(HANDLE hdir, struct emu_stat * st)
 	BY_HANDLE_FILE_INFORMATION fi;
 	if (!GetFileInformationByHandle(hdir, &fi))
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, "Failed to read file information: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		return -1;
 	}
 
 	if (INVALID_FILE_ATTRIBUTES == fi.dwFileAttributes)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, "Failed to get file attributes: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		return -1;
 	}
@@ -826,10 +836,10 @@ HANDLE OpenFileByNameUtf8(const char* pFileName, DWORD flags)
 
 	if (handle == INVALID_HANDLE_VALUE)
 	{
-		DWORD err = GetLastError();
+		winerrno = GetLastError();
 
-		if (err == ERROR_FILE_NOT_FOUND ||
-			err == ERROR_PATH_NOT_FOUND)
+		if (winerrno == ERROR_FILE_NOT_FOUND ||
+			winerrno == ERROR_PATH_NOT_FOUND)
 		{
 			errno = ENOENT;
 		}
@@ -837,7 +847,7 @@ HANDLE OpenFileByNameUtf8(const char* pFileName, DWORD flags)
 		{
 			::syslog(LOG_WARNING, "Failed to open '%s': "
 				"%s", pFileName, 
-				GetErrorMessage(err).c_str());
+				GetErrorMessage(winerrno).c_str());
 			errno = EACCES;
 		}
 
@@ -906,9 +916,10 @@ int statfs(const char * pName, struct statfs * s)
 	BY_HANDLE_FILE_INFORMATION fi;
 	if (!GetFileInformationByHandle(handle, &fi))
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_WARNING, "Failed to get file information "
 			"for '%s': %s", pName,
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		CloseHandle(handle);
 		errno = EACCES;
 		return -1;
@@ -961,8 +972,9 @@ int emu_utimes(const char * pName, const struct timeval times[])
 
 	if (!SetFileTime(handle, &creationTime, NULL, &modificationTime))
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set times on '%s': %s", pName,
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		CloseHandle(handle);
 		return 1;
 	}
@@ -1004,8 +1016,9 @@ int emu_chmod(const char * pName, mode_t mode)
 	DWORD attribs = GetFileAttributesW(pBuffer);
 	if (attribs == INVALID_FILE_ATTRIBUTES)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to get file attributes of '%s': %s",
-			pName, GetErrorMessage(GetLastError()).c_str());
+			pName, GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		free(pBuffer);
 		return -1;
@@ -1022,8 +1035,9 @@ int emu_chmod(const char * pName, mode_t mode)
 
 	if (!SetFileAttributesW(pBuffer, attribs))
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set file attributes of '%s': %s",
-			pName, GetErrorMessage(GetLastError()).c_str());
+			pName, GetErrorMessage(winerrno).c_str());
 		errno = EACCES;
 		free(pBuffer);
 		return -1;
@@ -1308,8 +1322,9 @@ BOOL AddEventSource
 
 	if (len == 0)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to get the program file name: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return FALSE;
 	}
 
@@ -1326,8 +1341,9 @@ BOOL AddEventSource
 			 0, NULL, REG_OPTION_NON_VOLATILE,
 			 KEY_WRITE, NULL, &hk, &dwDisp)) 
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to create the registry key: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return FALSE;
 	}
 
@@ -1340,8 +1356,9 @@ BOOL AddEventSource
 			   (LPBYTE)cmd,        // pointer to value data 
 			   len*sizeof(WCHAR))) // data size
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set the event message file: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		RegCloseKey(hk); 
 		return FALSE;
 	}
@@ -1358,8 +1375,9 @@ BOOL AddEventSource
 			  (LPBYTE) &dwData, // pointer to value data 
 			  sizeof(DWORD)))   // length of value data 
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set the supported types: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		RegCloseKey(hk); 
 		return FALSE;
 	}
@@ -1373,8 +1391,9 @@ BOOL AddEventSource
 			   (LPBYTE)cmd,           // pointer to value data 
 			   len*sizeof(WCHAR)))    // data size
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set the category message file: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		RegCloseKey(hk); 
 		return FALSE;
 	}
@@ -1386,8 +1405,9 @@ BOOL AddEventSource
 			  (LPBYTE) &dwNum, // pointer to value data 
 			  sizeof(DWORD)))  // length of value data 
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to set the category count: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		RegCloseKey(hk); 
 		return FALSE;
 	}
@@ -1427,8 +1447,9 @@ void openlog(const char * daemonName, int, int)
 	HANDLE newSyslogH = RegisterEventSource(NULL, nameStr.c_str());
 	if (newSyslogH == NULL)
 	{
+		winerrno = GetLastError();
 		::syslog(LOG_ERR, "Failed to register our own event source: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		return;
 	}
 
@@ -1540,8 +1561,8 @@ void syslog(int loglevel, const char *frmt, ...)
 		
 	if (result == 0)
 	{
-		DWORD err = GetLastError();
-		if (err == ERROR_LOG_FILE_FULL)
+		winerrno = GetLastError();
+		if (winerrno == ERROR_LOG_FILE_FULL)
 		{
 			if (!sHaveWarnedEventLogFull)
 			{
@@ -1554,7 +1575,7 @@ void syslog(int loglevel, const char *frmt, ...)
 		else
 		{
 			printf("Unable to send message to Event Log: %s:\r\n",
-				GetErrorMessage(err).c_str());
+				GetErrorMessage(winerrno).c_str());
 			fflush(stdout);
 		}
 	}
@@ -1588,8 +1609,9 @@ int emu_chdir(const char* pDirName)
 	if (result != 0) return 0;
 
 	errno = EACCES;
+	winerrno = GetLastError();
 	fprintf(stderr, "Failed to change directory to '%s': %s\n",
-		pDirName, GetErrorMessage(GetLastError()).c_str());
+		pDirName, GetErrorMessage(winerrno).c_str());
 	return -1;
 }
 
@@ -1701,21 +1723,22 @@ int emu_link(const char* pOldPath, const char* pNewPath)
 	}
 
 	BOOL result = CreateHardLinkW(pNewBuffer, pOldBuffer, NULL);
-	DWORD err = GetLastError();
+	winerrno = GetLastError();
 	delete [] pOldBuffer;
 	delete [] pNewBuffer;
 
 	if (!result)
 	{
-		if (err == ERROR_FILE_NOT_FOUND || err == ERROR_PATH_NOT_FOUND)
+		if (winerrno == ERROR_FILE_NOT_FOUND ||
+			winerrno == ERROR_PATH_NOT_FOUND)
 		{
 			errno = ENOENT;
 		}
-		else if (err == ERROR_SHARING_VIOLATION)
+		else if (winerrno == ERROR_SHARING_VIOLATION)
 		{
 			errno = EBUSY;
 		}
-		else if (err == ERROR_ACCESS_DENIED)
+		else if (winerrno == ERROR_ACCESS_DENIED)
 		{
 			errno = EACCES;
 		}
@@ -1723,7 +1746,7 @@ int emu_link(const char* pOldPath, const char* pNewPath)
 		{
 			::syslog(LOG_WARNING, "Failed to hardlink file "
 				"'%s' to '%s': %s", pOldPath, pNewPath,
-				GetErrorMessage(err).c_str());
+				GetErrorMessage(winerrno).c_str());
 			errno = ENOSYS;
 		}
 
@@ -1752,20 +1775,21 @@ int emu_unlink(const char* pFileName)
 	}
 
 	BOOL result = DeleteFileW(pBuffer);
-	DWORD err = GetLastError();
+	winerrno  = GetLastError();
 	delete [] pBuffer;
 
 	if (!result)
 	{
-		if (err == ERROR_FILE_NOT_FOUND || err == ERROR_PATH_NOT_FOUND)
+		if (winerrno == ERROR_FILE_NOT_FOUND ||
+			winerrno == ERROR_PATH_NOT_FOUND)
 		{
 			errno = ENOENT;
 		}
-		else if (err == ERROR_SHARING_VIOLATION)
+		else if (winerrno == ERROR_SHARING_VIOLATION)
 		{
 			errno = EBUSY;
 		}
-		else if (err == ERROR_ACCESS_DENIED)
+		else if (winerrno == ERROR_ACCESS_DENIED)
 		{
 			errno = EACCES;
 		}
@@ -1773,7 +1797,7 @@ int emu_unlink(const char* pFileName)
 		{
 			::syslog(LOG_WARNING, "Failed to delete file "
 				"'%s': %s", pFileName, 
-				GetErrorMessage(err).c_str());
+				GetErrorMessage(winerrno).c_str());
 			errno = ENOSYS;
 		}
 
@@ -1818,21 +1842,22 @@ int emu_rename(const char* pOldFileName, const char* pNewFileName)
 	}
 
 	BOOL result = MoveFileW(pOldBuffer, pNewBuffer);
-	DWORD err = GetLastError();
+	winerrno = GetLastError();
 	delete [] pOldBuffer;
 	delete [] pNewBuffer;
 
 	if (!result)
 	{
-		if (err == ERROR_FILE_NOT_FOUND || err == ERROR_PATH_NOT_FOUND)
+		if (winerrno == ERROR_FILE_NOT_FOUND ||
+			winerrno == ERROR_PATH_NOT_FOUND)
 		{
 			errno = ENOENT;
 		}
-		else if (err == ERROR_SHARING_VIOLATION)
+		else if (winerrno == ERROR_SHARING_VIOLATION)
 		{
 			errno = EBUSY;
 		}
-		else if (err == ERROR_ACCESS_DENIED)
+		else if (winerrno == ERROR_ACCESS_DENIED)
 		{
 			errno = EACCES;
 		}
@@ -1840,7 +1865,7 @@ int emu_rename(const char* pOldFileName, const char* pNewFileName)
 		{
 			::syslog(LOG_WARNING, "Failed to rename file "
 				"'%s' to '%s': %s", pOldFileName, pNewFileName,
-				GetErrorMessage(err).c_str());
+				GetErrorMessage(winerrno).c_str());
 			errno = ENOSYS;
 		}
 		return -1;
@@ -1855,8 +1880,9 @@ int console_read(char* pBuffer, size_t BufferSize)
 
 	if (hConsole == INVALID_HANDLE_VALUE)
 	{
+		winerrno = GetLastError();
 		::fprintf(stderr, "Failed to get a handle on standard input: "
-			"%s", GetErrorMessage(GetLastError()).c_str());
+			"%s", GetErrorMessage(winerrno).c_str());
 		return -1;
 	}
 
@@ -1879,8 +1905,9 @@ int console_read(char* pBuffer, size_t BufferSize)
 			NULL // reserved
 		)) 
 	{
+		winerrno = GetLastError();
 		::fprintf(stderr, "Failed to read from console: %s\n",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return -1;
 	}
 
@@ -1977,8 +2004,9 @@ bool ConvertTime_tToFileTime(const time_t from, FILETIME *pTo)
 	// Convert the last-write time to local time.
 	if (!SystemTimeToFileTime(&stUTC, pTo))
 	{
+		winerrno = GetLastError();
 		syslog(LOG_ERR, "Failed to convert between time formats: %s",
-			GetErrorMessage(GetLastError()).c_str());
+			GetErrorMessage(winerrno).c_str());
 		return false;
 	}