Add missing checks into db directory.

10 files changed, 56 insertions, 17 deletions

diff --git a/src/resources/db/chardb.cpp b/src/resources/db/chardb.cpp
index 9b6f24358..84cdd6327 100644
--- a/src/resources/db/chardb.cpp
+++ b/src/resources/db/chardb.cpp
@@ -102,8 +102,10 @@ void CharDB::loadMinMax(const XmlNodePtr node,
                         unsigned *restrict const min,
                         unsigned *restrict const max)
 {
-    *min = XML::getProperty(node, "min", 1);
-    *max = XML::getProperty(node, "max", 10);
+    if (min)
+        *min = XML::getProperty(node, "min", 1);
+    if (max)
+        *max = XML::getProperty(node, "max", 10);
 }
 
 void CharDB::unload()
diff --git a/src/resources/db/itemdb.cpp b/src/resources/db/itemdb.cpp
index d1ec2d00f..2b1601c76 100644
--- a/src/resources/db/itemdb.cpp
+++ b/src/resources/db/itemdb.cpp
@@ -57,16 +57,16 @@ namespace
 
 // Forward declarations
 static void loadSpriteRef(ItemInfo *const itemInfo,
-                          const XmlNodePtr node);
+                          const XmlNodePtr node) A_NONNULL(1);
 static void loadSoundRef(ItemInfo *const itemInfo,
-                         const XmlNodePtr node);
-static void loadFloorSprite(SpriteDisplay *const display,
+                         const XmlNodePtr node) A_NONNULL(1);
+static void loadFloorSprite(SpriteDisplay &display,
                             const XmlNodePtrConst node);
 static void loadReplaceSprite(ItemInfo *const itemInfo,
-                              const XmlNodePtr replaceNode);
+                              const XmlNodePtr replaceNode) A_NONNULL(1);
 static void loadOrderSprite(ItemInfo *const itemInfo,
                             const XmlNodePtr node,
-                            const bool drawAfter);
+                            const bool drawAfter) A_NONNULL(1);
 static int parseSpriteName(const std::string &name);
 static int parseDirectionName(const std::string &name);
 
@@ -453,7 +453,7 @@ void ItemDB::loadXmlFile(const std::string &fileName, int &tagNum)
             }
             else if (xmlNameEqual(itemChild, "floor"))
             {
-                loadFloorSprite(&display, itemChild);
+                loadFloorSprite(display, itemChild);
             }
             else if (xmlNameEqual(itemChild, "replace"))
             {
@@ -741,7 +741,7 @@ static int parseDirectionName(const std::string &name)
 static void loadSpriteRef(ItemInfo *const itemInfo, const XmlNodePtr node)
 {
     const std::string gender = XML::getProperty(node, "gender", "unisex");
-    if (!node->xmlChildrenNode)
+    if (!node || !node->xmlChildrenNode)
         return;
 
     const std::string filename = reinterpret_cast<const char*>(
@@ -758,7 +758,7 @@ static void loadSpriteRef(ItemInfo *const itemInfo, const XmlNodePtr node)
 
 static void loadSoundRef(ItemInfo *const itemInfo, const XmlNodePtr node)
 {
-    if (!node->xmlChildrenNode)
+    if (!node || !node->xmlChildrenNode)
         return;
     const std::string event = XML::getProperty(node, "event", "");
     const std::string filename = reinterpret_cast<const char*>(
@@ -778,9 +778,11 @@ static void loadSoundRef(ItemInfo *const itemInfo, const XmlNodePtr node)
     }
 }
 
-static void loadFloorSprite(SpriteDisplay *const display,
+static void loadFloorSprite(SpriteDisplay &display,
                             const XmlNodePtrConst floorNode)
 {
+    if (!floorNode)
+        return;
     for_each_xml_child_node(spriteNode, floorNode)
     {
         if (!spriteNode->xmlChildrenNode)
@@ -792,11 +794,11 @@ static void loadFloorSprite(SpriteDisplay *const display,
                 spriteNode->xmlChildrenNode->content);
             currentSprite->variant
                 = XML::getProperty(spriteNode, "variant", 0);
-            display->sprites.push_back(currentSprite);
+            display.sprites.push_back(currentSprite);
         }
         else if (xmlNameEqual(spriteNode, "particlefx"))
         {
-            display->particles.push_back(reinterpret_cast<const char*>(
+            display.particles.push_back(reinterpret_cast<const char*>(
                 spriteNode->xmlChildrenNode->content));
         }
     }
@@ -805,6 +807,8 @@ static void loadFloorSprite(SpriteDisplay *const display,
 static void loadReplaceSprite(ItemInfo *const itemInfo,
                               const XmlNodePtr replaceNode)
 {
+    if (!replaceNode)
+        return;
     const std::string removeSprite = XML::getProperty(
         replaceNode, "sprite", "");
     const int direction = parseDirectionName(XML::getProperty(
diff --git a/src/resources/db/mapdb.cpp b/src/resources/db/mapdb.cpp
index 1bd63af2f..44c37771b 100644
--- a/src/resources/db/mapdb.cpp
+++ b/src/resources/db/mapdb.cpp
@@ -98,6 +98,8 @@ void MapDB::loadRemapXmlFile(const std::string &fileName)
 
 void MapDB::readMap(XmlNodePtrConst node)
 {
+    if (!node)
+        return;
     const std::string map = XML::getProperty(node, "name", "");
     if (map.empty())
         return;
@@ -116,6 +118,8 @@ void MapDB::readMap(XmlNodePtrConst node)
 
 void MapDB::readAtlas(XmlNodePtrConst node)
 {
+    if (!node)
+        return;
     const std::string atlas = XML::getProperty(node, "name", "");
     if (atlas.empty())
         return;
diff --git a/src/utils/base64.cpp b/src/utils/base64.cpp
index 88fe8bf8f..7be63c090 100644
--- a/src/utils/base64.cpp
+++ b/src/utils/base64.cpp
@@ -42,8 +42,11 @@ static char base64_table[] =
 static const char base64_pad = '=';
 
 unsigned char *php3_base64_encode(const unsigned char *restrict const string,
-                                  int length, int *restrict const ret_length)
+                                  int length,
+                                  int *restrict const ret_length)
 {
+    if (!string)
+        return nullptr;
     const unsigned char *current = string;
     int i = 0;
     unsigned char *const result = static_cast<unsigned char *>(
diff --git a/src/utils/glxhelper.cpp b/src/utils/glxhelper.cpp
index 40f2b6f9f..42ac8ccb5 100644
--- a/src/utils/glxhelper.cpp
+++ b/src/utils/glxhelper.cpp
@@ -48,6 +48,8 @@ void *GlxHelper::createContext(const unsigned long window,
     XSync(display, false);
     int (*handler)(Display *, XErrorEvent *) = XSetErrorHandler(ErrorHandler);
     void *context = mglXGetCurrentContext();
+    if (!display)
+        return context;
     if (isGLNull(mglXGetCurrentContext)
         || isGLNull(mglXCreateContextAttribs)
         || isGLNull(mglXChooseFBConfig))
@@ -124,6 +126,8 @@ bool GlxHelper::makeCurrent(const unsigned long window,
                             void *const display,
                             void *const context)
 {
+    if (!display)
+        return false;
     return mglXMakeCurrent(static_cast<Display*>(display), window, context);
 }
 
diff --git a/src/utils/mutex.h b/src/utils/mutex.h
index 7fe3ad69c..d715dddad 100644
--- a/src/utils/mutex.h
+++ b/src/utils/mutex.h
@@ -90,12 +90,14 @@ inline void Mutex::unlock()
 inline MutexLocker::MutexLocker(Mutex *const mutex) :
     mMutex(mutex)
 {
-    mMutex->lock();
+    if (mMutex)
+        mMutex->lock();
 }
 
 inline MutexLocker::~MutexLocker()
 {
-    mMutex->unlock();
+    if (mMutex)
+        mMutex->unlock();
 }
 
 #endif  // UTILS_MUTEX_H
diff --git a/src/utils/physfsrwops.cpp b/src/utils/physfsrwops.cpp
index 10799b824..bc78d09cb 100644
--- a/src/utils/physfsrwops.cpp
+++ b/src/utils/physfsrwops.cpp
@@ -46,6 +46,8 @@ static int openedRWops = 0;
 static PHYSFSINT physfsrwops_seek(SDL_RWops *const rw, const PHYSFSINT offset,
                                   const int whence)
 {
+    if (!rw)
+        return -1;
     PHYSFS_file *const handle = static_cast<PHYSFS_file *const>(
         rw->hidden.unknown.data1);
     PHYSFSINT pos = 0;
@@ -115,10 +117,13 @@ static PHYSFSINT physfsrwops_seek(SDL_RWops *const rw, const PHYSFSINT offset,
     return pos;
 } /* physfsrwops_seek */
 
-static PHYSFSSIZE physfsrwops_read(SDL_RWops *const rw, void *ptr,
+static PHYSFSSIZE physfsrwops_read(SDL_RWops *const rw,
+                                   void *ptr,
                                    const PHYSFSSIZE size,
                                    const PHYSFSSIZE maxnum)
 {
+    if (!rw)
+        return 0;
     PHYSFS_file *const handle = static_cast<PHYSFS_file *const>(
         rw->hidden.unknown.data1);
     const PHYSFS_sint64 rc = PHYSFS_read(handle, ptr,
@@ -137,6 +142,8 @@ static PHYSFSSIZE physfsrwops_write(SDL_RWops *const rw, const void *ptr,
                                     const PHYSFSSIZE size,
                                     const PHYSFSSIZE num)
 {
+    if (!rw)
+        return 0;
     PHYSFS_file *const handle = static_cast<PHYSFS_file *const>(
         rw->hidden.unknown.data1);
     const PHYSFS_sint64 rc = PHYSFS_write(handle, ptr,
@@ -150,6 +157,8 @@ static PHYSFSSIZE physfsrwops_write(SDL_RWops *const rw, const void *ptr,
 
 static int physfsrwops_close(SDL_RWops *const rw)
 {
+    if (!rw)
+        return 0;
     PHYSFS_file *const handle = static_cast<PHYSFS_file*>(
         rw->hidden.unknown.data1);
     if (!PHYSFS_close(handle))
diff --git a/src/utils/sdlpixel.h b/src/utils/sdlpixel.h
index 4fb7cd774..6e78c184b 100644
--- a/src/utils/sdlpixel.h
+++ b/src/utils/sdlpixel.h
@@ -145,6 +145,11 @@ inline unsigned int SDLAlpha32(const unsigned int src,
     return (b & 0xff) | (g & 0xff00) | (r & 0xff0000);
 }
 
+inline unsigned short SDLAlpha16(const unsigned short src,
+                                 const unsigned short dst,
+                                 const unsigned char a,
+                                 const SDL_PixelFormat *const f) A_NONNULL(4);
+
 /**
   * Blends two 16 bit colors together.
   *
@@ -178,6 +183,8 @@ inline unsigned short SDLAlpha16(const unsigned short src,
 inline void SDLputPixelAlpha(SDL_Surface* surface, int x, int y,
                              const Color& color)
 {
+    if (!surface)
+        return;
     const int bpp = surface->format->BytesPerPixel;
 
     SDL_LockSurface(surface);
diff --git a/src/utils/stringutils.cpp b/src/utils/stringutils.cpp
index b6251a378..3e067fe5c 100644
--- a/src/utils/stringutils.cpp
+++ b/src/utils/stringutils.cpp
@@ -294,6 +294,8 @@ const char* getSafeUtf8String(const std::string &text)
 
 void getSafeUtf8String(std::string text, char *const buf)
 {
+    if (!buf)
+        return;
     const size_t sz = text.size();
     const size_t size = sz + UTF8_MAX_SIZE;
     if (size > 65500)
diff --git a/src/utils/xml.cpp b/src/utils/xml.cpp
index f2cbdb384..cb0cc56b8 100644
--- a/src/utils/xml.cpp
+++ b/src/utils/xml.cpp
@@ -245,6 +245,8 @@ namespace XML
     XmlNodePtr findFirstChildByName(const XmlNodePtrConst parent,
                                     const char *const name)
     {
+        if (!parent)
+            return nullptr;
         for_each_xml_child_node(child, parent)
         {
             if (xmlNameEqual(child, name))