Split SystemException to handle Windows

Windows has (at least) two error namespaces, both errno and
GetLastResult(). These overlap, so it is important we keep track of
which one we are dealing with.

To make things extra problematic, the BSD socket API normally uses
errno, but on Windows it has been mapped in to the GetLastResult()
namespace.

Try to keep better control of this by using separate classes for the
namespaces.

common/os/Mutex.cxx

@@ -43,7 +43,7 @@ Mutex::Mutex()
   systemMutex = new pthread_mutex_t;
   ret = pthread_mutex_init((pthread_mutex_t*)systemMutex, nullptr);
   if (ret != 0)
-    throw rdr::SystemException("Failed to create mutex", ret);
+    throw rdr::PosixException("Failed to create mutex", ret);
 #endif
 }
 
@@ -67,7 +67,7 @@ void Mutex::lock()
 
   ret = pthread_mutex_lock((pthread_mutex_t*)systemMutex);
   if (ret != 0)
-    throw rdr::SystemException("Failed to lock mutex", ret);
+    throw rdr::PosixException("Failed to lock mutex", ret);
 #endif
 }
 
@@ -80,7 +80,7 @@ void Mutex::unlock()
 
   ret = pthread_mutex_unlock((pthread_mutex_t*)systemMutex);
   if (ret != 0)
-    throw rdr::SystemException("Failed to unlock mutex", ret);
+    throw rdr::PosixException("Failed to unlock mutex", ret);
 #endif
 }
 
@@ -97,7 +97,7 @@ Condition::Condition(Mutex* mutex_)
   systemCondition = new pthread_cond_t;
   ret = pthread_cond_init((pthread_cond_t*)systemCondition, nullptr);
   if (ret != 0)
-    throw rdr::SystemException("Failed to create condition variable", ret);
+    throw rdr::PosixException("Failed to create condition variable", ret);
 #endif
 }
 
@@ -120,14 +120,14 @@ void Condition::wait()
                                  (CRITICAL_SECTION*)mutex->systemMutex,
                                  INFINITE);
   if (!ret)
-    throw rdr::SystemException("Failed to wait on condition variable", GetLastError());
+    throw rdr::Win32Exception("Failed to wait on condition variable", GetLastError());
 #else
   int ret;
 
   ret = pthread_cond_wait((pthread_cond_t*)systemCondition,
                           (pthread_mutex_t*)mutex->systemMutex);
   if (ret != 0)
-    throw rdr::SystemException("Failed to wait on condition variable", ret);
+    throw rdr::PosixException("Failed to wait on condition variable", ret);
 #endif
 }
 
@@ -140,7 +140,7 @@ void Condition::signal()
 
   ret = pthread_cond_signal((pthread_cond_t*)systemCondition);
   if (ret != 0)
-    throw rdr::SystemException("Failed to signal condition variable", ret);
+    throw rdr::PosixException("Failed to signal condition variable", ret);
 #endif
 }
 
@@ -153,6 +153,6 @@ void Condition::broadcast()
 
   ret = pthread_cond_broadcast((pthread_cond_t*)systemCondition);
   if (ret != 0)
-    throw rdr::SystemException("Failed to broadcast condition variable", ret);
+    throw rdr::PosixException("Failed to broadcast condition variable", ret);
 #endif
 }

common/os/Thread.cxx

@@ -66,7 +66,7 @@ void Thread::start()
 #ifdef WIN32
   *(HANDLE*)threadId = CreateThread(nullptr, 0, startRoutine, this, 0, nullptr);
   if (*(HANDLE*)threadId == nullptr)
-    throw rdr::SystemException("Failed to create thread", GetLastError());
+    throw rdr::Win32Exception("Failed to create thread", GetLastError());
 #else
   int ret;
   sigset_t all, old;
@@ -76,14 +76,14 @@ void Thread::start()
   sigfillset(&all);
   ret = pthread_sigmask(SIG_SETMASK, &all, &old);
   if (ret != 0)
-    throw rdr::SystemException("Failed to mask signals", ret);
+    throw rdr::PosixException("Failed to mask signals", ret);
 
   ret = pthread_create((pthread_t*)threadId, nullptr, startRoutine, this);
 
   pthread_sigmask(SIG_SETMASK, &old, nullptr);
 
   if (ret != 0)
-    throw rdr::SystemException("Failed to create thread", ret);
+    throw rdr::PosixException("Failed to create thread", ret);
 #endif
 
   running = true;
@@ -99,13 +99,13 @@ void Thread::wait()
 
   ret = WaitForSingleObject(*(HANDLE*)threadId, INFINITE);
   if (ret != WAIT_OBJECT_0)
-    throw rdr::SystemException("Failed to join thread", GetLastError());
+    throw rdr::Win32Exception("Failed to join thread", GetLastError());
 #else
   int ret;
 
   ret = pthread_join(*(pthread_t*)threadId, nullptr);
   if (ret != 0)
-    throw rdr::SystemException("Failed to join thread", ret);
+    throw rdr::PosixException("Failed to join thread", ret);
 #endif
 }
 

common/rdr/Exception.cxx

@@ -76,11 +76,23 @@ GAIException::GAIException(const char* s, int err_)
   strncat(str_, ")", len-1-strlen(str_));
 }
 
-SystemException::SystemException(const char* s, int err_)
+PosixException::PosixException(const char* s, int err_)
+  : Exception("%s", s), err(err_)
+{
+  strncat(str_, ": ", len-1-strlen(str_));
+  strncat(str_, strerror(err), len-1-strlen(str_));
+  strncat(str_, " (", len-1-strlen(str_));
+  char buf[20];
+    sprintf(buf,"%d",err);
+  strncat(str_, buf, len-1-strlen(str_));
+  strncat(str_, ")", len-1-strlen(str_));
+}
+
+#ifdef WIN32
+Win32Exception::Win32Exception(const char* s, unsigned err_)
   : Exception("%s", s), err(err_)
 {
   strncat(str_, ": ", len-1-strlen(str_));
-#ifdef _WIN32
   wchar_t *currStr = new wchar_t[len-strlen(str_)];
   FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                  nullptr, err, 0, currStr, len-1-strlen(str_), nullptr);
@@ -92,18 +104,10 @@ SystemException::SystemException(const char* s, int err_)
   if ((l >= 2) && (str_[l-2] == '\r') && (str_[l-1] == '\n'))
       str_[l-2] = 0;
 
-#else
-  strncat(str_, strerror(err), len-1-strlen(str_));
-#endif
   strncat(str_, " (", len-1-strlen(str_));
   char buf[20];
-#ifdef WIN32
-  if (err < 0)
-    sprintf(buf, "%x", err);
-  else
-#endif
-    sprintf(buf,"%d",err);
+  sprintf(buf,"%d",err);
   strncat(str_, buf, len-1-strlen(str_));
   strncat(str_, ")", len-1-strlen(str_));
 }
-
+#endif

common/rdr/Exception.h

@@ -32,14 +32,27 @@ namespace rdr {
     virtual const char* str() const { return str_; }
   };
 
-  struct SystemException : public Exception {
+  struct PosixException : public Exception {
     int err;
-    SystemException(const char* s, int err_);
+    PosixException(const char* s, int err_);
   };
 
-  struct SocketException : public SystemException {
-    SocketException(const char* text, int err_) : SystemException(text, err_) {}
+#ifdef WIN32
+  struct Win32Exception : public Exception {
+    unsigned err;
+    Win32Exception(const char* s, unsigned err_);
   };
+#endif
+
+#ifdef WIN32
+  struct SocketException : public Win32Exception {
+    SocketException(const char* text, unsigned err_) : Win32Exception(text, err_) {}
+  };
+#else
+  struct SocketException : public PosixException {
+    SocketException(const char* text, int err_) : PosixException(text, err_) {}
+  };
+#endif
 
   struct GAIException : public Exception {
     int err;

common/rdr/FileInStream.cxx

@@ -33,7 +33,7 @@ FileInStream::FileInStream(const char *fileName)
 {
   file = fopen(fileName, "rb");
   if (!file)
-    throw SystemException("fopen", errno);
+    throw PosixException("fopen", errno);
 }
 
 FileInStream::~FileInStream(void) {
@@ -48,7 +48,7 @@ bool FileInStream::fillBuffer()
   size_t n = fread((uint8_t*)end, 1, availSpace(), file);
   if (n == 0) {
     if (ferror(file))
-      throw SystemException("fread", errno);
+      throw PosixException("fread", errno);
     if (feof(file))
       throw EndOfStream();
     return false;

common/rdr/RandomStream.cxx

@@ -89,16 +89,16 @@ bool RandomStream::fillBuffer() {
 #ifdef RFB_HAVE_WINCRYPT
   if (provider) {
     if (!CryptGenRandom(provider, availSpace(), (uint8_t*)end))
-      throw rdr::SystemException("unable to CryptGenRandom", GetLastError());
+      throw rdr::Win32Exception("unable to CryptGenRandom", GetLastError());
     end += availSpace();
   } else {
 #else
 #ifndef WIN32
   if (fp) {
     size_t n = fread((uint8_t*)end, 1, availSpace(), fp);
     if (n <= 0)
-      throw rdr::SystemException("reading /dev/urandom or /dev/random failed",
-                                 errno);
+      throw rdr::PosixException("reading /dev/urandom or /dev/random failed",
+                                errno);
     end += n;
   } else {
 #else

common/rfb/SSecurityRSAAES.cxx

@@ -156,7 +156,7 @@ void SSecurityRSAAES::loadPrivateKey()
 {
   FILE* file = fopen(keyFile, "rb");
   if (!file)
-    throw rdr::SystemException("failed to open key file", errno);
+    throw rdr::PosixException("failed to open key file", errno);
   fseek(file, 0, SEEK_END);
   size_t size = ftell(file);
   if (size == 0 || size > MaxKeyFileSize) {
@@ -167,7 +167,7 @@ void SSecurityRSAAES::loadPrivateKey()
   std::vector<uint8_t> data(size);
   if (fread(data.data(), 1, data.size(), file) != size) {
     fclose(file);
-    throw rdr::SystemException("failed to read key", errno);
+    throw rdr::PosixException("failed to read key", errno);
   }
   fclose(file);
 

vncviewer/ServerDialog.cxx

@@ -359,7 +359,7 @@ void ServerDialog::loadServerHistory()
       return;
     }
     std::string msg = format(_("Could not open \"%s\""), filepath);
-    throw rdr::SystemException(msg.c_str(), errno);
+    throw rdr::PosixException(msg.c_str(), errno);
   }
 
   int lineNr = 0;
@@ -375,7 +375,7 @@ void ServerDialog::loadServerHistory()
       fclose(f);
       std::string msg = format(_("Failed to read line %d in "
                                  "file \"%s\""), lineNr, filepath);
-      throw rdr::SystemException(msg.c_str(), errno);
+      throw rdr::PosixException(msg.c_str(), errno);
     }
 
     int len = strlen(line);
@@ -431,7 +431,7 @@ void ServerDialog::saveServerHistory()
   FILE* f = fopen(filepath, "w+");
   if (!f) {
     std::string msg = format(_("Could not open \"%s\""), filepath);
-    throw rdr::SystemException(msg.c_str(), errno);
+    throw rdr::PosixException(msg.c_str(), errno);
   }
 
   // Save the last X elements to the config file.

vncviewer/Surface_Win32.cxx

@@ -57,10 +57,10 @@ void Surface::draw(int src_x, int src_y, int dst_x, int dst_y,
 
   dc = CreateCompatibleDC(fl_gc);
   if (!dc)
-    throw rdr::SystemException("CreateCompatibleDC", GetLastError());
+    throw rdr::Win32Exception("CreateCompatibleDC", GetLastError());
 
   if (!SelectObject(dc, bitmap))
-    throw rdr::SystemException("SelectObject", GetLastError());
+    throw rdr::Win32Exception("SelectObject", GetLastError());
 
   if (!BitBlt(fl_gc, dst_x, dst_y, dst_w, dst_h,
               dc, src_x, src_y, SRCCOPY)) {
@@ -70,7 +70,7 @@ void Surface::draw(int src_x, int src_y, int dst_x, int dst_y,
     // with it. For now, we've only seen this error and for this function
     // so only ignore this combination.
     if (GetLastError() != ERROR_INVALID_HANDLE)
-      throw rdr::SystemException("BitBlt", GetLastError());
+      throw rdr::Win32Exception("BitBlt", GetLastError());
   }
 
   DeleteDC(dc);
@@ -83,10 +83,10 @@ void Surface::draw(Surface* dst, int src_x, int src_y,
 
   dstdc = CreateCompatibleDC(nullptr);
   if (!dstdc)
-    throw rdr::SystemException("CreateCompatibleDC", GetLastError());
+    throw rdr::Win32Exception("CreateCompatibleDC", GetLastError());
 
   if (!SelectObject(dstdc, dst->bitmap))
-    throw rdr::SystemException("SelectObject", GetLastError());
+    throw rdr::Win32Exception("SelectObject", GetLastError());
 
   origdc = fl_gc;
   fl_gc = dstdc;
@@ -113,15 +113,15 @@ void Surface::blend(Surface* dst, int src_x, int src_y,
 
   dstdc = CreateCompatibleDC(nullptr);
   if (!dstdc)
-    throw rdr::SystemException("CreateCompatibleDC", GetLastError());
+    throw rdr::Win32Exception("CreateCompatibleDC", GetLastError());
   srcdc = CreateCompatibleDC(nullptr);
   if (!srcdc)
-    throw rdr::SystemException("CreateCompatibleDC", GetLastError());
+    throw rdr::Win32Exception("CreateCompatibleDC", GetLastError());
 
   if (!SelectObject(dstdc, dst->bitmap))
-    throw rdr::SystemException("SelectObject", GetLastError());
+    throw rdr::Win32Exception("SelectObject", GetLastError());
   if (!SelectObject(srcdc, bitmap))
-    throw rdr::SystemException("SelectObject", GetLastError());
+    throw rdr::Win32Exception("SelectObject", GetLastError());
 
   blend.BlendOp = AC_SRC_OVER;
   blend.BlendFlags = 0;
@@ -136,7 +136,7 @@ void Surface::blend(Surface* dst, int src_x, int src_y,
     // with it. For now, we've only seen this error and for this function
     // so only ignore this combination.
     if (GetLastError() != ERROR_INVALID_HANDLE)
-      throw rdr::SystemException("BitBlt", GetLastError());
+      throw rdr::Win32Exception("BitBlt", GetLastError());
   }
 
   DeleteDC(srcdc);
@@ -161,7 +161,7 @@ void Surface::alloc()
   bitmap = CreateDIBSection(nullptr, (BITMAPINFO*)&bih,
                             DIB_RGB_COLORS, (void**)&data, nullptr, 0);
   if (!bitmap)
-    throw rdr::SystemException("CreateDIBSection", GetLastError());
+    throw rdr::Win32Exception("CreateDIBSection", GetLastError());
 }
 
 void Surface::dealloc()

vncviewer/UserDialog.cxx

@@ -115,7 +115,7 @@ void UserDialog::getUserPasswd(bool secure_, std::string* user,
 
     fp = fopen(passwordFileName, "rb");
     if (!fp)
-      throw rdr::SystemException(_("Opening password file failed"), errno);
+      throw rdr::PosixException(_("Opening password file failed"), errno);
 
     obfPwd.resize(fread(obfPwd.data(), 1, obfPwd.size(), fp));
     fclose(fp);