log errno when failing to open a disk or folder. Better win32 errors

Log errno when failing to open a disk or folder (game scanner)
Better win32 error codes with GetLastError() for opendir, stat, access

core/deps/dirent/dirent.h

@@ -617,7 +617,7 @@ dirent_first(
         /* Failed to re-open directory: no directory entry in memory */
         dirp->cached = 0;
         datap = NULL;
-
+        dirent_set_errno(GetLastError()); /* Not a valid errno but better than nothing */
     }
     return datap;
 }
@@ -651,6 +651,8 @@ dirent_next(
             FindClose (dirp->handle);
             dirp->handle = INVALID_HANDLE_VALUE;
             p = NULL;
+            if (GetLastError() != ERROR_NO_MORE_FILES)
+            	dirent_set_errno(GetLastError());
         }
 
     } else {

core/imgread/cdi.cpp

@@ -11,7 +11,10 @@ Disc* cdi_parse(const char* file, std::vector<u8> *digest)
 	FILE *fsource = nowide::fopen(file, "rb");
 
 	if (fsource == nullptr)
+	{
+		WARN_LOG(COMMON, "Cannot open file '%s' errno %d", file, errno);
 		throw FlycastException(std::string("Cannot open CDI file ") + file);
+	}
 
 	image_s image = { 0 };
 	track_s track = { 0 };
@@ -81,7 +84,7 @@ Disc* cdi_parse(const char* file, std::vector<u8> *digest)
 					ft = false;
 					Session s;
 					s.StartFAD = track.pregap_length + track.start_lba;
-					s.FirstTrack=track.global_current_track;
+					s.FirstTrack = (u8)track.global_current_track;
 					rv->sessions.push_back(s);
 				}
 

core/imgread/chd.cpp

@@ -84,7 +84,10 @@ void CHDDisc::tryOpen(const char* file)
 {
 	fp = nowide::fopen(file, "rb");
 	if (fp == nullptr)
+	{
+		WARN_LOG(COMMON, "Cannot open file '%s' errno %d", file, errno);
 		throw FlycastException(std::string("Cannot open CHD file ") + file);
+	}
 
 	chd_error err = chd_open_file(fp, CHD_OPEN_READ, 0, &chd);
 
@@ -117,23 +120,23 @@ void CHDDisc::tryOpen(const char* file)
 		char type[16], subtype[16], pgtype[16], pgsub[16];
 		int tkid=-1, frames=0, pregap=0, postgap=0, padframes=0;
 
-		err = chd_get_metadata(chd, CDROM_TRACK_METADATA2_TAG, tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
+		err = chd_get_metadata(chd, CDROM_TRACK_METADATA2_TAG, (u32)tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
 		if (err == CHDERR_NONE)
 		{
 			//"TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d PREGAP:%d PGTYPE:%s PGSUB:%s POSTGAP:%d"
 			sscanf(temp, CDROM_TRACK_METADATA2_FORMAT, &tkid, type, subtype, &frames, &pregap, pgtype, pgsub, &postgap);
 		}
-		else if (CHDERR_NONE== (err = chd_get_metadata(chd, CDROM_TRACK_METADATA_TAG, tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags)) )
+		else if (CHDERR_NONE== (err = chd_get_metadata(chd, CDROM_TRACK_METADATA_TAG, (u32)tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags)) )
 		{
 			//CDROM_TRACK_METADATA_FORMAT	"TRACK:%d TYPE:%s SUBTYPE:%s FRAMES:%d"
 			sscanf(temp, CDROM_TRACK_METADATA_FORMAT, &tkid, type, subtype, &frames);
 		}
 		else
 		{
-			err = chd_get_metadata(chd, GDROM_OLD_METADATA_TAG, tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
+			err = chd_get_metadata(chd, GDROM_OLD_METADATA_TAG, (u32)tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
 			if (err != CHDERR_NONE)
 			{
-				err = chd_get_metadata(chd, GDROM_TRACK_METADATA_TAG, tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
+				err = chd_get_metadata(chd, GDROM_TRACK_METADATA_TAG, (u32)tracks.size(), temp, sizeof(temp), &temp_len, &tag, &flags);
 			}
 			if (err == CHDERR_NONE)
 			{

core/imgread/cue.cpp

@@ -53,7 +53,10 @@ Disc* cue_parse(const char* file, std::vector<u8> *digest)
 	FILE *fsource = nowide::fopen(file, "rb");
 
 	if (fsource == nullptr)
+	{
+		WARN_LOG(COMMON, "Cannot open file '%s' errno %d", file, errno);
 		throw FlycastException(std::string("Cannot open CUE file ") + file);
+	}
 
 	size_t cue_len = flycast::fsize(fsource);
 
@@ -107,7 +110,7 @@ Disc* cue_parse(const char* file, std::vector<u8> *digest)
 						current_fad += 11400;
 
 					Session ses;
-					ses.FirstTrack = disc->tracks.size() + 1;
+					ses.FirstTrack = (u8)disc->tracks.size() + 1;
 					ses.StartFAD = current_fad;
 					disc->sessions.push_back(ses);
 					DEBUG_LOG(GDROM, "session[%zd]: 1st track: %d FAD:%d", disc->sessions.size(), ses.FirstTrack, ses.StartFAD);

core/imgread/gdi.cpp

@@ -64,7 +64,10 @@ Disc* load_gdi(const char* file, std::vector<u8> *digest)
 {
 	FILE *t = nowide::fopen(file, "rb");
 	if (t == nullptr)
+	{
+		WARN_LOG(COMMON, "Cannot open file '%s' errno %d", file, errno);
 		throw FlycastException(std::string("Cannot open GDI file ") + file);
+	}
 
 	size_t gdi_len = flycast::fsize(t);
 

core/oslib/directory.h

@@ -80,18 +80,30 @@ inline int closedir(DIR *dirstream)
 	return ::_wclosedir((_WDIR *)dirstream);
 }
 
+inline static void _set_errno(int error)
+{
+#ifdef _MSC_VER
+	::_set_errno (error);
+#else
+	errno = error;
+#endif
+}
+
 inline int stat(const char *filename, struct stat *buf)
 {
 	nowide::wstackstring wname;
     if (!wname.convert(filename)) {
-    	errno = EINVAL;
+    	_set_errno(EINVAL);
     	return -1;
     }
 #ifdef TARGET_UWP
     WIN32_FILE_ATTRIBUTE_DATA attrs;
 	bool rc = GetFileAttributesExFromAppW(wname.c_str(),  GetFileExInfoStandard, &attrs);
 	if (!rc)
+	{
+		_set_errno(GetLastError());
 		return -1;
+	}
 	memset(buf, 0, sizeof(struct stat));
 	if (attrs.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
 		buf->st_mode = S_IFDIR;
@@ -129,16 +141,27 @@ inline int access(const char *filename, int how)
 {
 	nowide::wstackstring wname;
     if (!wname.convert(filename)) {
-    	errno = EINVAL;
+    	_set_errno(EINVAL);
     	return -1;
     }
 #ifdef TARGET_UWP
     WIN32_FILE_ATTRIBUTE_DATA attrs;
 	bool rc = GetFileAttributesExFromAppW(wname.c_str(),  GetFileExInfoStandard, &attrs);
 	if (!rc)
+	{
+		if (GetLastError() == ERROR_FILE_NOT_FOUND || GetLastError() == ERROR_PATH_NOT_FOUND)
+			_set_errno(ENOENT);
+		else  if (GetLastError() == ERROR_ACCESS_DENIED)
+			_set_errno(EACCES);
+		else
+			_set_errno(GetLastError());
 		return -1;
+	}
 	if (how != R_OK && (attrs.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
+	{
+		_set_errno(EACCES);
 		return -1;
+	}
 	else
 		return 0;
 #else
@@ -237,7 +260,10 @@ public:
 				{
 					struct stat st;
 					if (flycast::stat(childPath.c_str(), &st) != 0)
+					{
+						WARN_LOG(COMMON, "Cannot stat file '%s' errno 0x%x", childPath.c_str(), errno);
 						continue;
+					}
 					if (S_ISDIR(st.st_mode))
 						isDir = true;
 				}
@@ -250,7 +276,7 @@ public:
 				DIR *childDir = flycast::opendir(childPath.c_str());
 				if (childDir == nullptr)
 				{
-					INFO_LOG(COMMON, "Cannot read directory '%s'", childPath.c_str());
+					WARN_LOG(COMMON, "Cannot read subdirectory '%s' errno 0x%x", childPath.c_str(), errno);
 				}
 				else
 				{
@@ -275,7 +301,7 @@ public:
 	{
 		DIR *dir = flycast::opendir(root.c_str());
 		if (dir == nullptr)
-			INFO_LOG(COMMON, "Cannot read directory '%s'", root.c_str());
+			WARN_LOG(COMMON, "Cannot read directory '%s' errno 0x%x", root.c_str(), errno);
 
 		return {dir, root};
 	}