Adding LUA tutorials: lua_calls_C1 - lua_calls_C5

Adding blinker demo: lua_blink_led

lua/examples/lua_calls_C5/Makefile

@@ -0,0 +1,22 @@
+CC        = mipsel-openwrt-linux-gcc
+CXX       =  mipsel-openwrt-linux-g++
+OPENWRT_BUILD_DIR = /home/cain/Embedded/ingenic/sakc/build/openwrt-xburst/staging_dir/target-mipsel_uClibc-0.9.30.1
+INCLUDE   = -I. -I$(OPENWRT_BUILD_DIR)/usr/include/
+WARNINGS  = -Wcast-align -Wpacked -Wpadded -Wall 
+CCFLAGS   = ${INCLUDE} ${DEBUG} ${WARNINGS} -std=c99 -fPIC
+LDFLAGS   = -L$(OPENWRT_BUILD_DIR)/usr/lib -llua -ldl
+DEBUG     = -O3 -g0
+NANO_PATH = root@192.168.254.101:
+TARGET    = mylib
+
+$(TARGET):
+	$(CC)  $(CCFLAGS) $(LDFLAGS) -shared  liba.c liba_wrapper.c -o  $(TARGET).so
+
+.c.o:
+	$(CC) -c $(CCFLAGS) -o $@
+
+upload: $(TARGET)
+	scp $(TARGET).so test.lua $(NANO_PATH)
+	
+clean:
+	rm -f *.o $(TARGET).so

lua/examples/lua_calls_C5/liba.c

@@ -0,0 +1,40 @@
+#include <stdio.h>  
+#include <string.h>  
+#include "liba.h"  
+  
+#define ENTER do{printf("in %s \n" ,__FUNCTION__);}while(0);  
+  
+void lib_a_f_1()  
+{  
+ENTER  
+}  
+  
+int lib_a_f_2(int a , int b)  
+{  
+ ENTER  
+ return a * b ;  
+}  
+  
+  
+int lib_a_f_3(const char *s)  
+{  
+    ENTER   
+    return strlen(s);  
+}  
+  
+int lib_a_f_4(Point *in_t)  
+{  
+   ENTER  
+   return in_t->a * in_t->b ;  
+}  
+  
+  
+int lib_a_f_5(Point *out_t)  
+{  
+    ENTER  
+    
+    out_t->a = 20;   
+    out_t->b = 30;  
+  
+    return 0;  
+}  

lua/examples/lua_calls_C5/liba.h

@@ -0,0 +1,10 @@
+typedef struct tagT{  
+    int a ;   
+    int b ;  
+}Point;  
+  
+void lib_a_f_1(void);    
+int  lib_a_f_2(int a, int b);  
+int lib_a_f_3(const char *s);  
+int lib_a_f_4(Point *in_t);  
+int lib_a_f_5(Point *out_t); 

lua/examples/lua_calls_C5/liba_wrapper.c

@@ -0,0 +1,131 @@
+#include "liba.h"  
+  
+#include "lua.h"  
+#include "lualib.h"  
+#include "lauxlib.h"  
+  
+  
+//glue the luaVm and the actually libary  
+  
+static int lib_a_f_1_wrapper(lua_State * luaVM)  
+{  
+    // no parameters , just call  
+    lib_a_f_1();  
+    return 0;  
+}  
+  
+static int lib_a_f_2_wrapper(lua_State * L)  
+{  
+    // no parameters , just call  
+    int n = lua_gettop(L);  
+    //error checking & return back to lua scripter  
+    int a = lua_tonumber(L,1);  
+    int b = lua_tonumber(L,2);  
+  
+    int r = lib_a_f_2(a ,b );  
+  
+    lua_pushnumber(L,r);  
+    return 1;  
+}  
+  
+  
+static int lib_a_f_3_wrapper(lua_State * L)  
+{  
+    // no parameters , just call  
+    int n = lua_gettop(L);  
+  
+    //error checking & return back to lua scripter  
+    const char *s = lua_tostring(L,1);  
+  
+    int r = lib_a_f_3(s);  
+  
+    lua_pushnumber(L,r);  
+  
+    return 1;  
+}  
+  
+const char *metaname = "mine.Point"; // associated with userdata of type Point*  
+  
+static int lib_a_f_4_wrapper(lua_State *L) {  
+    Point *t = luaL_checkudata(L, 1, metaname);  // check argument type  
+    lua_pushnumber(L, (lua_Number)lib_a_f_4(t));  
+    return 1;  
+}  
+  
+static int point_new_wrapper(lua_State *L) { // get Lua to allocate an initialize a Point*  
+    int a = luaL_checkint(L, 1);  
+    int b = luaL_checkint(L, 2);  
+    //create user data and associate metable with it  
+    Point *t = lua_newuserdata(L, sizeof(*t));  
+    luaL_getmetatable(L, metaname);  
+    lua_setmetatable(L, -2);  
+    t->a = a;  
+    t->b = b;  
+    return 1;  
+}  
+  
+static int point_geta_wrapper(lua_State *L)  
+{  
+    Point *t = luaL_checkudata(L, 1, metaname);   
+    lua_pushnumber(L,t->a);  
+  
+    return 1;  
+}  
+  
+static int point_getb_wrapper(lua_State *L)  
+{  
+    Point *t = luaL_checkudata(L, 1, metaname);   
+    lua_pushnumber(L,t->b);  
+  
+    return 1;  
+}  
+  
+static int lib_a_f_5_wrapper(lua_State *L)   
+{  
+    // Point *t = luaL_checkudata(L, 1, metaname);  // check argument type  
+    // lua_pushnumber(L, (lua_Number)lib_a_f_4(t));  
+  
+    Point t ;  
+    lib_a_f_5(&t);  
+    Point *r = lua_newuserdata(L,sizeof(*r));  
+    luaL_getmetatable(L, metaname);  
+    //It will Pops a table from the stack and   
+    //sets it as the new metatable for the value at the given acceptable index.   
+    //so , after this function , it is the userdata at the top of the stack.   
+    lua_setmetatable(L, -2);  
+    r->a = t.a;  
+    r->b = t.b;  
+    return 1;  
+}  
+  
+  
+static const struct luaL_reg functions[] = {  
+    {"lib_a_f_1", lib_a_f_1_wrapper},  
+    {"lib_a_f_2", lib_a_f_2_wrapper},  
+    {"lib_a_f_3", lib_a_f_3_wrapper},  
+    {"lib_a_f_4", lib_a_f_4_wrapper},  
+    {"lib_a_f_5", lib_a_f_5_wrapper},  
+    {"point_new", point_new_wrapper},  
+    {"point_geta", point_geta_wrapper},  
+    {"point_getb", point_getb_wrapper},  
+    { NULL, NULL}  
+};  
+  
+//This is the init function that will be called when you require 'mylib'  
+  
+int luaopen_mylib(lua_State *L) {  
+  
+  
+    luaL_newmetatable(L, metaname);  
+    //pop 1 elements from the statck .. why?? to pop the newmetatable that is useless.  
+    //  
+    //lua_pop(L, 1);  
+    //replace luaL_openlib  
+    {
+        lua_pop(L, 1);
+        luaL_newmetatable(L,metaname);
+        return 1;
+    }
+    luaL_register(L, "mylib", functions);  
+    return 1;  
+}  

lua/examples/lua_calls_C5/test.lua

@@ -0,0 +1,16 @@
+package.cpath = "./?.so"
+require "mylib"
+--test1  
+mylib.lib_a_f_1()  
+--test2   
+assert(6==mylib.lib_a_f_2(2,3))  
+--test3  
+assert(5==mylib.lib_a_f_3("hello"))  
+--test4 : use userdata to pass structure  
+t=mylib.point_new(3,6)  
+assert(18 == mylib.lib_a_f_4(t))  
+--test5, return userdata  
+t=mylib.lib_a_f_5()  
+assert(600 == mylib.lib_a_f_4(t))  
+assert(mylib.point_geta(t) == 20)  
+assert(mylib.point_getb(t) == 30)