add byteutil library

2024-12-27 08:33:52 +03:00
parent 83d8254d69
commit cca153b66b
6 changed files with 253 additions and 28 deletions
@@ -0,0 +1,194 @@
+#include "api_lua.hpp"
+
+#include <string>
+
+#include "coders/byte_utils.hpp"
+#include "util/data_io.hpp"
+
+static size_t calc_size(const char* format) {
+    size_t outSize = 0;
+    for (size_t i = 0; format[i]; i++) {
+        switch (format[i]) {
+            case 'b':
+            case 'B':
+                outSize += 1;
+                break;
+            case 'h':
+            case 'H':
+                outSize += 2;
+                break;
+            case 'i':
+            case 'I':
+            case 'f':
+                outSize += 4;
+                break;
+            case 'd':
+            case 'l':
+            case 'L':
+                outSize += 8;
+                break;
+            default:
+                break;
+        }
+    }
+    return outSize;
+}
+
+static int pack(lua::State* L, const char* format, bool usetable) {
+    size_t outSize = calc_size(format);
+    bool bigEndian = false;
+
+    ByteBuilder builder(outSize);
+    int index = 2;
+    for (int i = 0; format[i]; i++) {
+        switch (format[i]) {
+            case 'b':
+                builder.put(lua::tointeger(L, index) & 0xFF);
+                break;
+            case 'h':
+                builder.putInt16(lua::tointeger(L, index), bigEndian);
+                break;
+            case 'H':
+                builder.putInt16(lua::tointeger(L, index) & 0xFFFFU, bigEndian);
+                break;
+            case 'i':
+                builder.putInt32(lua::tointeger(L, index), bigEndian);
+                break;
+            case 'I':
+                builder.putInt32(lua::tointeger(L, index) & 0xFFFFFFFFULL, bigEndian);
+                break;
+            case 'l':
+            case 'L':
+                builder.putInt64(lua::tointeger(L, index), bigEndian);
+                break;
+            case 'f':
+                builder.putFloat32(lua::tonumber(L, index), bigEndian);
+                break;
+            case 'd':
+                builder.putFloat64(lua::tonumber(L, index), bigEndian);
+                break;
+            case '!':
+            case '>':
+                bigEndian = true;
+                continue;
+            case '<':
+                bigEndian = false;
+                continue;
+            case '@':
+            case '=':
+                bigEndian = dataio::is_big_endian();
+                continue;
+            default:
+                continue;
+        }
+        index++;
+    }
+    if (usetable) {
+        lua::createtable(L, outSize, 0);
+        const ubyte* data = builder.data();
+        for (size_t i = 0; i < outSize; i++) {
+            lua::pushinteger(L, data[i]);
+            lua::rawseti(L, i + 1);
+        }
+        return 1;
+    } else {
+        return lua::newuserdata<lua::LuaBytearray>(L, builder.build());
+    }
+}
+
+static int count_elements(const char* format) {
+    int count = 0;
+    for (size_t i = 0; format[i]; i++) {
+        switch (format[i]) {
+            case 'b':
+            case 'B':
+            case 'h':
+            case 'H':
+            case 'i':
+            case 'I':
+            case 'l':
+            case 'L':
+            case 'f':
+            case 'd':
+                count++;
+                break;
+            default:
+                break;
+        }
+    }
+    return count;
+}
+
+static int l_unpack(lua::State* L) {
+    const char* format = lua::require_string(L, 1);
+    int count = count_elements(format);
+    auto bytes = lua::require_bytearray(L, 2);
+    ByteReader reader(bytes);
+    bool bigEndian = false;
+
+    int index = 1;
+    lua::createtable(L, count, 0);
+    for (size_t i = 0; format[i]; i++) {
+        switch (format[i]) {
+            case 'b':
+                lua::pushinteger(L, reader.get());
+                break;
+            case 'h':
+                lua::pushinteger(L, reader.getInt16(bigEndian));
+                break;
+            case 'H':
+                lua::pushinteger(L, reader.getInt16(bigEndian) & 0xFFFF);
+                break;
+            case 'i':
+                lua::pushinteger(L, reader.getInt32(bigEndian));
+                break;
+            case 'I':
+                lua::pushinteger(L, reader.getInt32(bigEndian) & 0xFFFFFFFF);
+                break;
+            case 'l':
+                lua::pushinteger(L, reader.getInt64(bigEndian));
+                break;
+            case 'L':
+                lua::pushinteger(L, reader.getInt64(bigEndian));
+                break;
+            case 'f':
+                lua::pushnumber(L, reader.getFloat32(bigEndian));
+                break;
+            case 'd':
+                lua::pushnumber(L, reader.getFloat64(bigEndian));
+                break;
+            case '!':
+            case '>':
+                bigEndian = true;
+                continue;
+            case '<':
+                bigEndian = false;
+                continue;
+            case '@':
+            case '=':
+                bigEndian = dataio::is_big_endian();
+                continue;
+            default:
+                continue;
+        }
+        lua::rawseti(L, index++);
+    }
+    return 1;
+}
+
+static int l_pack(lua::State* L) {
+    const char* format = lua::require_string(L, 1);
+    return pack(L, format, false);
+}
+
+static int l_tpack(lua::State* L) {
+    const char* format = lua::require_string(L, 1);
+    return pack(L, format, true);
+}
+
+const luaL_Reg byteutillib[] = {
+    {"pack", l_pack},
+    {"tpack", l_tpack},
+    {"unpack", l_unpack},
+    {NULL, NULL}
+};