[vfs #1] Add ttvfs, miniz, and minihttp sources

ExternalLibs/ttvfs/VFSArchiveLoader.h

@@ -0,0 +1,68 @@
+#ifndef VFS_ARCHIVE_LOADER_H
+#define VFS_ARCHIVE_LOADER_H
+
+#include "VFSDefines.h"
+
+VFS_NAMESPACE_START
+
+class VFSDir;
+class VFSFile;
+class VFSLoader;
+
+// Generic Archive loader interface that is supposed to return a valid VFSDir pointer when it
+// was able to load 'arch' as an archive, and NULL if there was an error or the loader is
+// unable to load that file type.
+// 'asSubdir' - if this is true, the archive will be accessible as a folder (as in "test.zip/file.dat"),
+//              otherwise the files are mounted in place of the archive.
+// 'ldr' - can be set to an external file loader in case the file/folder tree can not be fully generated
+//         at load time.
+// 'opaque' - a POD struct which *must* have a `void (*)(void*, void*, const char*)`
+//            function pointer as first member (at offset 0).
+//            The struct pointer is then passed to that function, along with a pointer to an internal object,
+//            whatever this is. The derived loader knows what this object is - something that this callback
+//            will be interested in modifying, anyways. The rest of the struct can carry the data required to
+//            modify this object.
+//            The const char parameter is a string unique for each loader (to prevent accessing the pointer
+//            in a wrong way by the wrong loader). Example below.
+class VFSArchiveLoader
+{
+public:
+    virtual ~VFSArchiveLoader() {}
+
+    virtual VFSDir *Load(VFSFile *arch, VFSLoader **ldr, void *opaque = NULL) = 0;
+};
+
+/* A possible struct for 'opaque' would be:
+
+struct ExampleLoadParams
+{
+    void (*callback)(void *, void *, const char *);
+    const char *key;
+    unsigned int keylen;
+};
+
+And then the call would look like:
+(Assuming PakFile is an archive file class that represents an archive)
+
+void pakSetup(void *data, void *arch, const char *id)
+{
+    if(strcmp(id, "pak")) // Be sure we're in the right loader.
+        return;
+    ExampleLoadParams *pm = (ExampleLoadParams*)p;
+    PakArchive *pak = (PakArchive*)arch;
+    pak->SetKey(pm->key, pm->keylen);
+}
+
+ExampleLoadParams p;
+p.callback = &pakSetup;
+p.key = "123456";
+p.keylen = 6;
+vfs.AddArchive("data.pak", false, "", &p);
+
+Where p in turn will be passed to the PAK loader.
+
+*/
+
+VFS_NAMESPACE_END
+
+#endif