From da6f343032cb01597dc7866e66f091adf3243a62 Mon Sep 17 00:00:00 2001 From: Michael Smith Date: Sat, 20 Nov 2021 03:10:50 +0000 Subject: Initial public snapshot With code from Bill. Thanks Bill! --- src/abi.h | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 src/abi.h (limited to 'src/abi.h') diff --git a/src/abi.h b/src/abi.h new file mode 100644 index 0000000..54c504a --- /dev/null +++ b/src/abi.h @@ -0,0 +1,91 @@ +/* + * Copyright © 2021 Michael Smith + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH + * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR + * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + * PERFORMANCE OF THIS SOFTWARE. + */ + +#ifndef INC_ABI_H +#define INC_ABI_H + +#include "intdefs.h" + +/* + * This file defines miscellaneous C++ ABI stuff. Looking at it may cause + * brain damage and/or emotional trauma. + */ + +#ifdef _WIN32 // Windows RTTI stuff, obviously only used on Windows. + +// MSVC RTTI is quite a black box, but thankfully there's some useful sources: +// - https://doxygen.reactos.org/d0/dcf/cxx_8h_source.html +// - https://blog.quarkslab.com/visual-c-rtti-inspection.html +// - https://www.geoffchappell.com/studies/msvc/language/predefined/ +// - https://docs.rs/pelite/0.5.0/src/pelite/pe32/msvc.rs.html + +// By the way, while I'm here I'd just like to point out how ridiculous this +// layout is. Whoever decided to put this many levels of indirection over what +// should be a small lookup table is an absolute nutcase. I hope that individual +// has gotten some help by now, mostly for the sake of others. + +struct msvc_rtti_descriptor { + void *vtab; + void *unknown; // ??? + // XXX: pretty sure this is supposed to be flexible, but too lazy to write + // the stupid union init macros to make that fully portable + char classname[80]; +}; + +// "pointer to member displacement" +struct msvc_pmd { int mdisp, pdisp, vdisp; }; + +struct msvc_basedesc { + struct msvc_rtti_descriptor *desc; + uint nbases; + struct msvc_pmd where; + uint attr; +}; + +struct msvc_rtti_hierarchy { + uint sig; + uint attrs; + uint nbaseclasses; + struct msvc_basedesc **baseclasses; +}; + +struct msvc_rtti_locator { + uint sig; + int baseoff; + // ctor offset, or some flags; reactos and rust pelite say different things? + int unknown; + struct msvc_rtti_descriptor *desc; + struct msvc_rtti_hierarchy *hier; +}; + +// I mean seriously look at this crap! +#define DEF_MSVC_BASIC_RTTI(mod, name, vtab, typestr) \ +mod struct msvc_rtti_locator name; \ +static struct msvc_rtti_descriptor _desc_##name = {(vtab) + 1, 0, typestr}; \ +static struct msvc_basedesc _basedesc_##name = {&_desc_##name, 0, {0, 0, 0}, 0}; \ +mod struct msvc_rtti_locator name = { \ + 0, 0, 0, \ + &_desc_##name, \ + &(struct msvc_rtti_hierarchy){ \ + 0, 1 /* per engine */, 1, (struct msvc_basedesc *[]){&_basedesc_##name} \ + } \ +}; + +#endif + +#endif + +// vi: sw=4 ts=4 noet tw=80 cc=80 -- cgit v1.2.3