Fix clang-analyzer-optin.portability.UnixAPI

and mark some false positives

/media/ddnet/src/engine/client/backend_sdl.cpp:329:30: warning: Call to 'malloc' has an allocation size of 0 bytes [clang-analyzer-optin.portability.UnixAPI]

src/engine/client/backend_sdl.cpp

@@ -326,7 +326,9 @@ void *CCommandProcessorFragment_OpenGL::Resize(int Width, int Height, int NewWid
 
 	int Bpp = TexFormatToImageColorChannelCount(Format);
 
-	pTmpData = (unsigned char *)malloc((size_t)NewWidth * NewHeight * Bpp);
+	// All calls to Resize() ensure width & height are > 0, Bpp is always > 0,
+	// thus no allocation size 0 possible.
+	pTmpData = (unsigned char *)malloc((size_t)NewWidth * NewHeight * Bpp); // NOLINT(clang-analyzer-optin.portability.UnixAPI)
 
 	ResizeImage((uint8_t *)pData, Width, Height, (uint8_t *)pTmpData, NewWidth, NewHeight, Bpp);
 

src/engine/shared/demo.cpp

@@ -531,9 +531,12 @@ void CDemoPlayer::ScanFile()
 	}
 
 	// copy all the frames to an array instead for fast access
+	if(m_Info.m_SeekablePoints > 0)
+	{
 		m_pKeyFrames = (CKeyFrame *)calloc(m_Info.m_SeekablePoints, sizeof(CKeyFrame));
 		for(pCurrentKey = pFirstKey, i = 0; pCurrentKey; pCurrentKey = pCurrentKey->m_pNext, i++)
 			m_pKeyFrames[i] = pCurrentKey->m_Frame;
+	}
 
 	// destroy the temporary heap and seek back to the start
 	io_seek(m_File, StartPos, IOSEEK_START);
@@ -1040,8 +1043,11 @@ int CDemoPlayer::Stop()
 		m_pConsole->Print(IConsole::OUTPUT_LEVEL_STANDARD, "demo_player", "Stopped playback");
 	io_close(m_File);
 	m_File = 0;
+	if(m_pKeyFrames)
+	{
 		free(m_pKeyFrames);
 		m_pKeyFrames = 0;
+	}
 	str_copy(m_aFilename, "", sizeof(m_aFilename));
 	return 0;
 }

src/game/client/components/mapimages.cpp

@@ -217,7 +217,7 @@ IGraphics::CTextureHandle CMapImages::GetEntities(EMapImageEntityLayerType Entit
 
 		if(ImagePNGLoaded && ImgInfo.m_Width > 0 && ImgInfo.m_Height > 0)
 		{
-			int ColorChannelCount = 0;
+			int ColorChannelCount = 4;
 			if(ImgInfo.m_Format == CImageInfo::FORMAT_ALPHA)
 				ColorChannelCount = 1;
 			else if(ImgInfo.m_Format == CImageInfo::FORMAT_RGB)

src/game/editor/io.cpp

@@ -270,7 +270,8 @@ int CEditorMap::Save(class IStorage *pStorage, const char *pFileName)
 				Size += str_length(m_lSettings[i].m_aCommand) + 1;
 			}
 
-			char *pSettings = (char *)malloc(Size);
+			// Checked that m_lSettings.size() is not 0, thus Size is > 0 as ell
+			char *pSettings = (char *)malloc(Size); // NOLINT(clang-analyzer-optin.portability.UnixAPI)
 			char *pNext = pSettings;
 			for(int i = 0; i < m_lSettings.size(); i++)
 			{
@@ -542,6 +543,8 @@ int CEditorMap::Save(class IStorage *pStorage, const char *pFileName)
 		PointCount += Item.m_NumPoints;
 	}
 
+	if(PointCount > 0)
+	{
 		// save points
 		int TotalSize = sizeof(CEnvPoint) * PointCount;
 		CEnvPoint *pPoints = (CEnvPoint *)calloc(PointCount, sizeof(*pPoints));
@@ -556,6 +559,7 @@ int CEditorMap::Save(class IStorage *pStorage, const char *pFileName)
 
 		df.AddItem(MAPITEMTYPE_ENVPOINTS, 0, TotalSize, pPoints);
 		free(pPoints);
+	}
 
 	// finish the data file
 	df.Finish();

src/game/server/gamecontext.cpp

@@ -3335,7 +3335,7 @@ void CGameContext::OnMapChange(char *pNewMapName, int MapNameSize)
 	}
 	io_close(File);
 
-	char *pSettings = (char *)malloc(TotalLength);
+	char *pSettings = (char *)malloc(maximum(1, TotalLength));
 	int Offset = 0;
 	for(int i = 0; i < aLines.size(); i++)
 	{
@@ -3374,6 +3374,7 @@ void CGameContext::OnMapChange(char *pNewMapName, int MapNameSize)
 					if(DataSize == TotalLength && mem_comp(pSettings, pMapSettings, DataSize) == 0)
 					{
 						// Configs coincide, no need to update map.
+						free(pSettings);
 						return;
 					}
 					Reader.UnloadData(pInfo->m_Settings);
@@ -3423,6 +3424,7 @@ void CGameContext::OnMapChange(char *pNewMapName, int MapNameSize)
 	}
 
 	dbg_msg("mapchange", "imported settings");
+	free(pSettings);
 	Reader.Close();
 	Writer.OpenFile(Storage(), aTemp);
 	Writer.Finish();

src/tools/config_store.cpp

@@ -31,7 +31,7 @@ void Process(IStorage *pStorage, const char *pMapName, const char *pConfigName)
 	}
 	io_close(File);
 
-	pSettings = (char *)malloc(TotalLength);
+	pSettings = (char *)malloc(maximum(1, TotalLength));
 	int Offset = 0;
 	for(int i = 0; i < aLines.size(); i++)
 	{
@@ -73,6 +73,7 @@ void Process(IStorage *pStorage, const char *pMapName, const char *pConfigName)
 					if(DataSize == TotalLength && mem_comp(pSettings, pMapSettings, DataSize) == 0)
 					{
 						dbg_msg("config_store", "configs coincide, not updating map");
+						free(pSettings);
 						return;
 					}
 					Reader.UnloadData(pInfo->m_Settings);
@@ -121,6 +122,7 @@ void Process(IStorage *pStorage, const char *pMapName, const char *pConfigName)
 		Reader.UnloadData(i);
 	}
 
+	free(pSettings);
 	Reader.Close();
 	if(!Writer.OpenFile(pStorage, pMapName))
 	{