Merge pull request #1573 from nicolasnoble/file-null-fix

Fixing nullchecks on the File object.

Author: nicolasnoble

src/core/sio1.cc

@@ -144,7 +144,7 @@ void PCSX::SIO1::interrupt() {
 
 uint8_t PCSX::SIO1::readData8() {
     updateStat();
-    if (m_sio1fifo || !m_sio1fifo->eof()) {
+    if (m_sio1fifo && !m_sio1fifo->eof()) {
         if (m_regs.status & SR_RXRDY) {
             m_regs.data = m_sio1fifo->byte();
             g_emulator->m_mem->writeHardwareRegister<0x1050, uint8_t>(m_regs.data);
@@ -156,7 +156,7 @@ uint8_t PCSX::SIO1::readData8() {
 
 uint16_t PCSX::SIO1::readData16() {
     updateStat();
-    if (m_sio1fifo || !m_sio1fifo->eof()) {
+    if (m_sio1fifo && !m_sio1fifo->eof()) {
         if (m_regs.status & SR_RXRDY) {
             m_sio1fifo->read(&m_regs.data, 2);
             g_emulator->m_mem->writeHardwareRegister<0x1050, uint16_t>(m_regs.data);
@@ -168,7 +168,7 @@ uint16_t PCSX::SIO1::readData16() {
 
 uint32_t PCSX::SIO1::readData32() {
     updateStat();
-    if (m_sio1fifo || !m_sio1fifo->eof()) {
+    if (m_sio1fifo && !m_sio1fifo->eof()) {
         if (m_regs.status & SR_RXRDY) {
             m_sio1fifo->read(&m_regs.data, 4);
             g_emulator->m_mem->writeHardwareRegister<0x1050, uint32_t>(m_regs.data);

src/support/file.h

@@ -326,7 +326,8 @@ class IO : public IOBase {
         if (!r) throw std::runtime_error("operator-> used with incompatible type - shouldn't happen");
         return r;
     }
-    bool isNull() { return dynamic_cast<T*>(m_file); }
+    bool isNull() const { return !dynamic_cast<T*>(m_file); }
+    operator bool() const { return !isNull(); }
 };
 
 class FailedFile : public File {