[英]How to statically inialize an array of structures?
struct A{
int a; int b;
};
static const struct A a = {.a1 = 1, .a2 = 42};
struct B{
struct A[666][510]
};
static const struct B b;
我想用b
的副本初始化b
。 但是,我不能用memcpy()
觸摸static const
事物。 我需要b
是static const
,因為它被放入flash而不是ram內存。
我該如何做這項工作。 我認為編譯器是arm-none-eabi-gcc
, -std=c89
。
我建議您將這些數組放在單獨的模塊中以實現封裝。 然后在該模塊中,您不需要將B設為const而是將其設為靜態。 任何對此數據的訪問都必須通過這樣的getter和setter來完成:
mydata.h
#define BA_SIZE 666
struct A{
int a; int b;
};
struct B{
struct A stuff[BA_SIZE];
};
void init(void);
struct A * getB(unsigned int i);
void setB(unsigned int i, struct A element);
mydata.c:
#include "mydata.h"
static const struct A a = {.a = 1, .b = 42};
static struct B b;
void init(void)
{
int i;
for(i=0; i<BA_SIZE; i++) {
b.stuff[i] = a;
}
}
struct A * getB(unsigned int i)
{
return(&b.stuff[i]);
}
void setB(unsigned int i, struct A element)
{
if (i > BA_SIZE) { return; }
b.stuff[i].a = element.a;
b.stuff[i].b = element.b;
}
main.c:
#include <stdio.h>
#include "mydata.h"
int main(void)
{
init();
unsigned int num=1;
struct A * something = getB(num);
printf("element [%u] a=%i b=%i \n", num, something->a, something->b);
return(0);
}
您可以試試這個,雖然它專門針對您指定的尺寸(666 x 510):
#define X001 {1,42}
#define X002 X001,X001
#define X004 X002,X002
#define X008 X004,X004
#define X016 X008,X008
#define X032 X016,X016
#define X064 X032,X032
#define X128 X064,X064
#define X256 X128,X128
#define Y001 {X256,X128,X064,X032,X016,X008,X004,X002}
#define Y002 Y001,Y001
#define Y004 Y002,Y002
#define Y008 Y004,Y004
#define Y016 Y008,Y008
#define Y032 Y016,Y016
#define Y064 Y032,Y032
#define Y128 Y064,Y064
#define Y256 Y128,Y128
#define Y512 Y256,Y256
static const struct A a = X001;
static const struct B b = {{Y512,Y128,Y016,Y008,Y002}};
在linux上這符合gcc -std = c89(不知道arm交叉編譯器)
typedef struct A{ int a; int b; } TA; typedef struct ARR3 { TA a[3]; } TARR3; typedef struct ARR33 { TARR3 b[3]; } TARR33; static const TA a = {.a = 1, .b = 42}; TARR33 aa = { .b[0] = { .a[0] = {.a = 1, .b = 1}, .a[1] = {.a = 2, .b = 2}, .a[2] = {.a = 3, .b = 3} }, .b[1] = { .a[0] = {.a = 4, .b = 4}, .a[1] = {.a = 5, .b = 5}, .a[2] = {.a = 1, .b = 2} }, .b[2] = { .a[0] = {.a = 1, .b = 1}, .a[1] = {.a = 1, .b = 2}, .a[2] = {.a = 1, .b = 2} } }; main() { return 0; }
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.