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#include <pcp/pmapi.h>
#include <pcp/impl.h>
typedef struct {
unsigned int a:16;
unsigned int b:7;
unsigned int c:3;
unsigned int d:3;
unsigned int e:3;
unsigned int f:4;
unsigned int g:12;
} ext_bits_t;
typedef struct {
unsigned int a:16;
unsigned int b:7;
unsigned int c:3;
unsigned int d:3;
unsigned int e:3;
unsigned int f:4;
unsigned int g:12;
} bits_t;
bits_t outbits = { 0xdead, 0x5f, 0x3, 0x5, 0x7, 0xc, 0xafe };
int
main(int argc, char *argv[])
{
bits_t inbits;
ext_bits_t extbits;
__uint32_t *ip;
int i;
int sts;
fprintf(stderr, "sizeof(bits_t): %d\n", (int)sizeof(bits_t));
if (strcmp(basename(argv[0]), "read-bf") == 0) {
sts = read(0, &extbits, sizeof(ext_bits_t));
if (sts != sizeof(ext_bits_t)) {
fprintf(stderr, "read() returns %d not %d as expected\n", sts, (int)sizeof(ext_bits_t));
exit(1);
}
fprintf(stderr, "read: ");
for (i = 0, ip = (__uint32_t *)&extbits; i < sizeof(ext_bits_t); i += sizeof(*ip), ip++)
fprintf(stderr, " %08x", *ip);
fputc('\n', stderr);
/*
* swap bytes, then assign fields
*/
for (i = 0, ip = (__uint32_t *)&extbits; i < sizeof(ext_bits_t); i += sizeof(*ip), ip++)
*ip = ntohl(*ip);
inbits.a = extbits.a;
inbits.b = extbits.b;
inbits.c = extbits.c;
inbits.d = extbits.d;
inbits.e = extbits.e;
inbits.f = extbits.f;
inbits.g = extbits.g;
if (inbits.a != outbits.a)
fprintf(stderr, "Error: \"a\" got %x expected %x\n", inbits.a, outbits.a);
if (inbits.b != outbits.b)
fprintf(stderr, "Error: \"b\" got %x expected %x\n", inbits.b, outbits.b);
if (inbits.c != outbits.c)
fprintf(stderr, "Error: \"c\" got %x expected %x\n", inbits.c, outbits.c);
if (inbits.d != outbits.d)
fprintf(stderr, "Error: \"d\" got %x expected %x\n", inbits.d, outbits.d);
if (inbits.e != outbits.e)
fprintf(stderr, "Error: \"e\" got %x expected %x\n", inbits.e, outbits.e);
if (inbits.f != outbits.f)
fprintf(stderr, "Error: \"f\" got %x expected %x\n", inbits.f, outbits.f);
if (inbits.g != outbits.g)
fprintf(stderr, "Error: \"g\" got %x expected %x\n", inbits.g, outbits.g);
}
else {
/*
* assign fields, then swap bytes
*/
memset(&extbits, 0, sizeof(ext_bits_t));
extbits.a = outbits.a;
extbits.b = outbits.b;
extbits.c = outbits.c;
extbits.d = outbits.d;
extbits.e = outbits.e;
extbits.f = outbits.f;
extbits.g = outbits.g;
for (i = 0, ip = (__uint32_t *)&extbits; i < sizeof(ext_bits_t); i += sizeof(*ip), ip++)
*ip = htonl(*ip);
fprintf(stderr, "write: ");
for (i = 0, ip = (__uint32_t *)&extbits; i < sizeof(ext_bits_t); i += sizeof(*ip), ip++)
fprintf(stderr, " %08x", *ip);
fputc('\n', stderr);
sts = write(1, &extbits, sizeof(bits_t));
if (sts != sizeof(bits_t)) {
fprintf(stderr, "write() returns %d not %d as expected\n", sts, (int)sizeof(bits_t));
exit(1);
}
}
exit(0);
}
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