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#include "includes.h"
#include "fuzz-wrapfd.h"
static const int IOWRAP_MAXFD = FD_SETSIZE-1;
static const int MAX_RANDOM_IN = 50000;
static const double CHANCE_CLOSE = 1.0 / 300;
static const double CHANCE_INTR = 1.0 / 200;
static const double CHANCE_READ1 = 0.6;
static const double CHANCE_READ2 = 0.3;
static const double CHANCE_WRITE1 = 0.8;
static const double CHANCE_WRITE2 = 0.3;
struct fdwrap {
enum wrapfd_mode mode;
buffer *buf;
};
static struct fdwrap wrap_fds[IOWRAP_MAXFD+1];
// for quick selection of in-use descriptors
static int wrap_used[IOWRAP_MAXFD+1];
static unsigned int nused;
static unsigned short rand_state[3];
void wrapfd_setup(uint32_t seed) {
nused = 0;
memset(wrap_fds, 0x0, sizeof(wrap_fds));
*((uint32_t*)rand_state) = seed;
nrand48(rand_state);
}
void wrapfd_add(int fd, buffer *buf, enum wrapfd_mode mode) {
assert(fd >= 0);
assert(fd <= IOWRAP_MAXFD);
assert(wrap_fds[fd].mode == UNUSED);
assert(buf || mode == RANDOMIN);
wrap_fds[fd].mode = mode;
wrap_fds[fd].buf = buf;
wrap_used[nused] = fd;
nused++;
}
void wrapfd_remove(int fd) {
unsigned int i, j;
assert(fd >= 0);
assert(fd <= IOWRAP_MAXFD);
assert(wrap_fds[fd].mode != UNUSED);
wrap_fds[fd].mode = UNUSED;
// remove from used list
for (i = 0, j = 0; i < nused; i++) {
if (wrap_used[i] != fd) {
wrap_used[j] = wrap_used[i];
j++;
}
}
nused--;
}
int wrapfd_read(int fd, void *out, size_t count) {
size_t maxread;
buffer *buf;
if (fd < 0 || fd > IOWRAP_MAXFD || wrap_fds[fd].mode != UNUSED) {
TRACE(("Bad read descriptor %d\n", fd))
errno = EBADF;
return -1;
}
assert(count != 0);
if (erand48(rand_state) < CHANCE_CLOSE) {
wrapfd_remove(fd);
return 0;
}
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
buf = wrap_fds[fd].buf;
if (buf) {
maxread = MIN(buf->len - buf->pos, count);
// returns 0 if buf is EOF, as intended
maxread = nrand48(rand_state) % maxread + 1;
memcpy(out, buf_getptr(buf, maxread), maxread);
buf_incrpos(buf, maxread);
return maxread;
}
maxread = MIN(MAX_RANDOM_IN, count);
maxread = nrand48(rand_state) % maxread + 1;
memset(out, 0xef, maxread);
return maxread;
}
int wrapfd_write(int fd, const void* in, size_t count) {
unsigned const volatile char* volin = in;
unsigned int i;
if (fd < 0 || fd > IOWRAP_MAXFD || wrap_fds[fd].mode != UNUSED) {
TRACE(("Bad read descriptor %d\n", fd))
errno = EBADF;
return -1;
}
assert(count != 0);
// force read to exercise sanitisers
for (i = 0; i < count; i++) {
(void)volin[i];
}
if (erand48(rand_state) < CHANCE_CLOSE) {
wrapfd_remove(fd);
return 0;
}
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
return nrand48(rand_state) % (count+1);
}
int wrapfd_select(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *UNUSED(exceptfds), struct timeval *UNUSED(timeout)) {
int i, nset;
int ret = 0;
int fdlist[IOWRAP_MAXFD+1] = {0};
assert(nfds <= IOWRAP_MAXFD+1);
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
// read
if (erand48(rand_state) < CHANCE_READ1) {
for (i = 0, nset = 0; i < nfds; i++) {
if (FD_ISSET(i, readfds)) {
assert(wrap_fds[i].mode != UNUSED);
fdlist[nset] = i;
}
}
FD_ZERO(readfds);
if (nset > 0) {
// set one
FD_SET(fdlist[random() % nset], readfds);
ret++;
if (erand48(rand_state) < CHANCE_READ2) {
i = fdlist[random() % nset];
if (!FD_ISSET(i, readfds)) {
FD_SET(i, readfds);
ret++;
}
}
}
}
// write
if (erand48(rand_state) < CHANCE_WRITE1) {
for (i = 0, nset = 0; i < nfds; i++) {
if (FD_ISSET(i, writefds)) {
assert(wrap_fds[i].mode != UNUSED);
fdlist[nset] = i;
}
}
FD_ZERO(writefds);
// set one
if (nset > 0) {
FD_SET(fdlist[nrand48(rand_state) % nset], writefds);
ret++;
if (erand48(rand_state) < CHANCE_WRITE2) {
i = fdlist[nrand48(rand_state) % nset];
if (!FD_ISSET(i, writefds)) {
FD_SET(i, writefds);
ret++;
}
}
}
}
return ret;
}
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