Throw some more exceptions.

libdevcore/CommonIO.cpp

@@ -95,11 +95,12 @@ string dev::contentsString(string const& _file)
 	return contentsGeneric<string>(_file);
 }
 
-bool dev::writeFile(std::string const& _file, bytesConstRef _data)
+void dev::writeFile(std::string const& _file, bytesConstRef _data)
 {
 	ofstream s(_file, ios::trunc | ios::binary);
 	s.write(reinterpret_cast<char const*>(_data.data()), _data.size());
-	return !!s;
+	if (!s)
+		BOOST_THROW_EXCEPTION(FileError());
 }
 
 std::string dev::getPassword(std::string const& _prompt)

libdevcore/CommonIO.h

@@ -56,11 +56,11 @@ std::string contentsString(std::string const& _file);
 bytesRef contentsNew(std::string const& _file, bytesRef _dest = bytesRef());
 
 /// Write the given binary data into the given file, replacing the file if it pre-exists.
-/// @returns true if writing succeeded.
-bool writeFile(std::string const& _file, bytesConstRef _data);
+/// Throws exception on error.
+void writeFile(std::string const& _file, bytesConstRef _data);
 /// Write the given binary data into the given file, replacing the file if it pre-exists.
-inline bool writeFile(std::string const& _file, bytes const& _data) { return writeFile(_file, bytesConstRef(&_data)); }
-inline bool writeFile(std::string const& _file, std::string const& _data) { return writeFile(_file, bytesConstRef(_data)); }
+inline void writeFile(std::string const& _file, bytes const& _data) { writeFile(_file, bytesConstRef(&_data)); }
+inline void writeFile(std::string const& _file, std::string const& _data) { writeFile(_file, bytesConstRef(_data)); }
 
 /// Nicely renders the given bytes to a string, optionally as HTML.
 /// @a _bytes: bytes array to be rendered as string. @a _width of a bytes line.

libdevcrypto/Common.cpp

@@ -31,6 +31,7 @@
 #include <libdevcore/FileSystem.h>
 #include "AES.h"
 #include "CryptoPP.h"
+#include "Exceptions.h"
 using namespace std;
 using namespace dev;
 using namespace dev::crypto;
@@ -188,7 +189,7 @@ bytes dev::pbkdf2(string const& _pass, bytes const& _salt, unsigned _iterations,
 		_salt.size(),
 		_iterations
 	) != _iterations)
-		return bytes();
+		BOOST_THROW_EXCEPTION(CryptoException());
 	return ret;
 }
 
@@ -206,7 +207,7 @@ bytes dev::scrypt(std::string const& _pass, bytes const& _salt, uint64_t _n, uin
 		ret.data(),
 		ret.size()
 	) != 0)
-		return bytes();
+		BOOST_THROW_EXCEPTION(CryptoException());
 	return ret;
 }
 

libdevcrypto/Exceptions.h

@@ -0,0 +1,35 @@
+/*
+	This file is part of cpp-ethereum.
+
+	cpp-ethereum is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	cpp-ethereum is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file Exceptions.h
+ * @author Christian <c@ethdev.com>
+ * @date 2016
+ */
+
+#pragma once
+
+#include <libdevcore/Exceptions.h>
+
+namespace dev
+{
+namespace crypto
+{
+
+/// Rare malfunction of cryptographic functions.
+DEV_SIMPLE_EXCEPTION_RLP(CryptoException);
+
+}
+}

libdevcrypto/SecretStore.cpp

@@ -149,12 +149,10 @@ void SecretStore::save(string const& _keysPath)
 		v["crypto"] = crypto;
 		v["id"] = uuid;
 		v["version"] = c_keyFileVersion;
-		if (writeFile(filename, js::write_string(js::mValue(v), true)))
-		{
-			swap(k.second.filename, filename);
-			if (!filename.empty() && !fs::equivalent(filename, k.second.filename))
-				fs::remove(filename);
-		}
+		writeFile(filename, js::write_string(js::mValue(v), true));
+		swap(k.second.filename, filename);
+		if (!filename.empty() && !fs::equivalent(filename, k.second.filename))
+			fs::remove(filename);
 	}
 }
 

libdevcrypto/SecretStore.h

@@ -40,7 +40,8 @@ enum class KDF {
  * and changes to the keys are automatically synced to the directory.
  * Each file stores exactly one key in a specific JSON format whose file name is derived from the
  * UUID of the key.
- * @note that most of the functions here affect the filesystem and throw exceptions on failure.
+ * @note that most of the functions here affect the filesystem and throw exceptions on failure,
+ * and they also throw exceptions upon rare malfunction in the cryptographic functions.
  */
 class SecretStore
 {