add: 加上zbuff库的雏形

luat/include/luat_base.h

@@ -104,6 +104,8 @@ LUAMOD_API int luaopen_libgnss( lua_State *L ) ;
 LUAMOD_API int luaopen_fatfs( lua_State *L );
 LUAMOD_API int luaopen_eink( lua_State *L);
 LUAMOD_API int luaopen_dbg( lua_State *L );
+/** 加载zbuff库, 可选,平台无关*/
+LUAMOD_API int luaopen_zbuff( lua_State *L );
 
 /** sprintf需要支持longlong值的打印, 提供平台无关的实现*/
 int l_sprintf(char *buf, size_t size, const char *fmt, ...);

luat/include/luat_zbuff.h

@@ -0,0 +1,12 @@
+#ifndef LUAT_ZBUFF
+#define LUAT_ZBUFF
+
+#include "luat_msgbus.h"
+
+typedef struct luat_zbuff {
+    uint8_t* addr;      //数据存储的地址
+    uint32_t len;       //数据的长度
+    uint32_t cursor;    //目前的指针位置
+} luat_zbuff;
+
+#endif

luat/modules/luat_lib_zbuff.c

@@ -0,0 +1,197 @@
+/*
+@module  zbuff
+@summary 直接指向一块内存区域,提供一系列API操作这块内存
+@version 0.1
+@date    2021.03.31
+*/
+#include "luat_base.h"
+#include "luat_zbuff.h"
+
+#define LUAT_LOG_TAG "luat.zbuff"
+#include "luat_log.h"
+
+#define LUAT_ZBUFF_TYPE "ZBUFF*"
+
+#define tozbuff(L) ((luat_zbuff *)luaL_checkudata(L, 1, LUAT_ZBUFF_TYPE))
+
+/* Fill memory block */
+static void mem_set(void *dst, int val, uint32_t cnt)
+{
+    uint8_t *d = (uint8_t *)dst;
+
+    do
+    {
+        *d++ = (uint8_t)val;
+    } while (--cnt);
+}
+
+/**
+创建zbuff
+@api zbuff.create()
+@int 字节数
+@string 可选参数，填充字符串
+@return object zbuff对象，如果创建失败会返回nil
+@usage
+-- 创建zbuff
+local buff = zbuff.create(1024) -- 空白的
+local buff = zbuff.create(1024, "123321456654") -- 创建，并填充一个已有字符串的内容
+ */
+static int l_zbuff_create(lua_State *L)
+{
+
+    int len = luaL_checkinteger(L, 1);
+    if (len <= 0)
+    {
+        return 0;
+    }
+
+    luat_zbuff *buff = (luat_zbuff *)lua_newuserdata(L, sizeof(luat_zbuff));
+
+    if (buff == NULL)
+    {
+        return 0;
+    }
+    buff->addr = (uint8_t *)luat_heap_malloc(len);
+    if (buff->addr == NULL)
+    {
+        return 0;
+    }
+
+    mem_set(buff->addr, 0, len);
+    buff->len = len;
+    buff->cursor = 0;
+
+    if (lua_isstring(L, 2))
+    {
+        char *data = luaL_optlstring(L, 2, "", &len);
+
+        memcpy(buff->addr, data, len);
+
+        buff->cursor = len;
+    }
+
+    luaL_setmetatable(L, LUAT_ZBUFF_TYPE);
+    return 1;
+}
+
+/**
+zbuff写数据
+@api buff:write()
+@string 写入buff的数据
+@return boolean 写入结果，成功返回true，失败返回false
+@usage
+-- 类file的读写操作
+buff:write("123") -- 写入数据, 指针相应地往后移动
+ */
+static int l_zbuff_write(lua_State *L)
+{
+    int len;
+    char *data = luaL_checklstring(L, 2, &len);
+    luat_zbuff *buff = tozbuff(L);
+    if (buff == NULL)
+    {
+        lua_pushboolean(L, 0);
+        return 1;
+    }
+
+    memcpy(&(buff->addr[buff->cursor]), data, len);
+
+    buff->cursor = buff->cursor + len;
+
+    lua_pushboolean(L, 1);
+    return 1;
+}
+
+/**
+zbuff读数据
+@api buff:read()
+@int 读取buff中的字节数
+@return string 读取结果
+@usage
+-- 类file的读写操作
+local str = buff:read(3)
+ */
+static int l_zbuff_read(lua_State *L)
+{
+    luat_zbuff *buff = tozbuff(L);
+
+    int read_num = luaL_optinteger(L, 2, 0);
+    char *return_str = (char *)luat_heap_malloc(read_num);
+    memcpy(return_str, &(buff->addr[buff->cursor]), read_num);
+    lua_pushlstring(L, return_str, read_num);
+    buff->cursor = buff->cursor + read_num;
+    return 1;
+}
+
+/**
+zbuff设置光标位置
+@api buff:seek()
+@int whence, 基点，基点可以是"zbuff.SEEK_SET": 基点为 0 （文件开头）；"zbuff.SEEK_CUR": 基点为当前位置；"zbuff.SEEK_END": 基点为文件尾；
+@return int 设置光标后从buff开头计算起的光标的位置
+@usage
+buff:seek(zbuff.SEEK_SET, 0) -- 把光标设置到指定位置
+ */
+static int l_zbuff_seek(lua_State *L)
+{
+    luat_zbuff *buff = tozbuff(L);
+
+    int whence = luaL_optinteger(L, 2, 0);
+    int offset = luaL_optinteger(L, 3, 0);
+    switch (whence)
+    {
+    case 0:
+        buff->cursor = 0 + offset;
+        break;
+    case 1:
+        buff->cursor = buff->cursor + offset;
+        break;
+    case 2:
+        buff->cursor = buff->len + offset;
+        break;
+    default:
+        return 0;
+    }
+    lua_pushinteger(L, buff->cursor);
+    return 1;
+}
+
+// __gc
+static int l_zbuff_gc(lua_State *L)
+{
+    luat_zbuff *buff = tozbuff(L);
+    luat_heap_free(buff->addr);
+    LLOGD("GC");
+    return 0;
+}
+
+static const luaL_Reg lib_zbuff[] = {
+    {"write", l_zbuff_write},
+    {"read", l_zbuff_read},
+    {"seek", l_zbuff_seek},
+    {"__gc", l_zbuff_gc},
+    {NULL, NULL}};
+
+static void createmeta(lua_State *L)
+{
+    luaL_newmetatable(L, LUAT_ZBUFF_TYPE); /* create metatable for file handles */
+    lua_pushvalue(L, -1);                  /* push metatable */
+    lua_setfield(L, -2, "__index");        /* metatable.__index = metatable */
+    luaL_setfuncs(L, lib_zbuff, 0);        /* add file methods to new metatable */
+    lua_pop(L, 1);                         /* pop new metatable */
+}
+
+#include "rotable.h"
+static const rotable_Reg reg_zbuff[] =
+    {
+        {"create", l_zbuff_create, 0},
+        {"SEEK_SET", NULL, 0},
+        {"SEEK_CUR", NULL, 1},
+        {"SEEK_END", NULL, 2},
+        {NULL, NULL, 0}};
+
+LUAMOD_API int luaopen_zbuff(lua_State *L)
+{
+    rotable_newlib(L, reg_zbuff);
+    createmeta(L);
+    return 1;
+}

luat/rtt/luat_rtt_base.c

@@ -49,6 +49,7 @@ static const luaL_Reg loadedlibs[] = {
   {"pack", luaopen_pack},             // pack.pack/pack.unpack
   {"uart", luaopen_uart},             // 串口操作
   {"mqttcore",luaopen_mqttcore},      // MQTT 协议封装
+  {"zbuff",luaopen_zbuff},            // zbuff库
 //  {"utest", luaopen_utest},
 #ifdef RT_USING_PIN
   {"gpio", luaopen_gpio},              // GPIO脚的操作