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#include "test.h"
#include <string.h>
#include <stdint.h>
typedef struct {
union {
uint32_t x;
uint64_t y;
} u;
uint32_t version;
uint8_t flags[4];
} ControlFile;
int main(void) {
ControlFile cf;
// Zero the whole struct (mimics memset in write_gvar_data)
memset(&cf, 0, sizeof(cf));
// Initialize union member 'x'
cf.u.x = 0x12345678;
// Initialize version
cf.version = 42;
// Initialize flags array
cf.flags[0] = 1;
cf.flags[1] = 2;
cf.flags[2] = 3;
cf.flags[3] = 4;
// "Write" the struct to a buffer
uint8_t buf[sizeof(ControlFile)];
memcpy(buf, &cf, sizeof(cf));
// Print buffer contents in hex
printf("Buffer bytes:\n");
for (size_t i = 0; i < sizeof(buf); i++) {
printf("%02x ", buf[i]);
if ((i + 1) % 8 == 0) printf("\n");
}
ASSERT(0x78, buf[0]);
ASSERT(0x56, buf[1]);
ASSERT(0x34, buf[2]);
ASSERT(0x12, buf[3]);
ASSERT(0x00, buf[4]);
ASSERT(0x00, buf[5]);
ASSERT(0x00, buf[6]);
ASSERT(0x00, buf[7]);
ASSERT(0x2a, buf[8]);
ASSERT(0x00, buf[9]);
ASSERT(0x00, buf[10]);
ASSERT(0x00, buf[11]);
ASSERT(0x01, buf[12]);
ASSERT(0x02, buf[13]);
ASSERT(0x03, buf[14]);
ASSERT(0x04, buf[15]);
return 0;
}
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