From fb1808b185a63dc9855f75cd282899d2bbcfe684 Mon Sep 17 00:00:00 2001 From: Kim Alvefur Date: Sat, 7 Sep 2019 13:37:47 +0200 Subject: util.strbitop: Library for bitwise operations on strings --- util-src/GNUmakefile | 2 +- util-src/makefile | 2 +- util-src/strbitop.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 93 insertions(+), 2 deletions(-) create mode 100644 util-src/strbitop.c (limited to 'util-src') diff --git a/util-src/GNUmakefile b/util-src/GNUmakefile index 054c9201..a8b3529f 100644 --- a/util-src/GNUmakefile +++ b/util-src/GNUmakefile @@ -7,7 +7,7 @@ INSTALL_DATA=install -m644 TARGET?=../util/ ALL=encodings.so hashes.so net.so pposix.so signal.so table.so \ - ringbuffer.so time.so poll.so compat.so + ringbuffer.so time.so poll.so compat.so strbitop.so ifdef RANDOM ALL+=crand.so diff --git a/util-src/makefile b/util-src/makefile index 700633b4..02bad40a 100644 --- a/util-src/makefile +++ b/util-src/makefile @@ -6,7 +6,7 @@ INSTALL_DATA=install -m644 TARGET?=../util/ ALL=encodings.so hashes.so net.so pposix.so signal.so table.so \ - ringbuffer.so time.so poll.so compat.so + ringbuffer.so time.so poll.so compat.so strbitop.so .ifdef $(RANDOM) ALL+=crand.so diff --git a/util-src/strbitop.c b/util-src/strbitop.c new file mode 100644 index 00000000..a26288e5 --- /dev/null +++ b/util-src/strbitop.c @@ -0,0 +1,91 @@ +/* + * This project is MIT licensed. Please see the + * COPYING file in the source package for more information. + * + * Copyright (C) 2016 Kim Alvefur + */ + +#include +#include + +#if (LUA_VERSION_NUM == 501) +#define luaL_setfuncs(L, R, N) luaL_register(L, NULL, R) +#endif + +/* TODO Deduplicate code somehow */ + +int strop_and(lua_State* L) { + luaL_Buffer buf; + size_t a, b, i; + const char* str_a = luaL_checklstring(L, 1, &a); + const char* str_b = luaL_checklstring(L, 2, &b); + + luaL_buffinit(L, &buf); + + if(a == 0 || b == 0) { + lua_settop(L, 1); + return 1; + } + + for(i = 0; i < a; i++) { + luaL_addchar(&buf, str_a[i] & str_b[i % b]); + } + + luaL_pushresult(&buf); + return 1; +} + +int strop_or(lua_State* L) { + luaL_Buffer buf; + size_t a, b, i; + const char* str_a = luaL_checklstring(L, 1, &a); + const char* str_b = luaL_checklstring(L, 2, &b); + + luaL_buffinit(L, &buf); + + if(a == 0 || b == 0) { + lua_settop(L, 1); + return 1; + } + + for(i = 0; i < a; i++) { + luaL_addchar(&buf, str_a[i] | str_b[i % b]); + } + + luaL_pushresult(&buf); + return 1; +} + +int strop_xor(lua_State* L) { + luaL_Buffer buf; + size_t a, b, i; + const char* str_a = luaL_checklstring(L, 1, &a); + const char* str_b = luaL_checklstring(L, 2, &b); + + luaL_buffinit(L, &buf); + + if(a == 0 || b == 0) { + lua_settop(L, 1); + return 1; + } + + for(i = 0; i < a; i++) { + luaL_addchar(&buf, str_a[i] ^ str_b[i % b]); + } + + luaL_pushresult(&buf); + return 1; +} + +LUA_API int luaopen_util_strbitop(lua_State *L) { + luaL_Reg exports[] = { + { "sand", strop_and }, + { "sor", strop_or }, + { "sxor", strop_xor }, + { NULL, NULL } + }; + + lua_newtable(L); + luaL_setfuncs(L, exports, 0); + return 1; +} -- cgit v1.2.3