unsigned int failtest_timeout_ms = 20000;
const char *failpath;
+const char *debugpath;
enum info_type {
WRITE,
UNEXPECTED
};
-struct write_info_hdr {
- size_t len;
- off_t offset;
- int fd;
-};
-
-struct write_info {
- struct write_info_hdr hdr;
- char *data;
-};
-
struct lock_info {
int fd;
/* end is inclusive: you can't have a 0-byte lock. */
static int control_fd = -1;
static struct timeval start;
-static struct write_info *writes = NULL;
-static unsigned int writes_num = 0;
-
-static struct write_info *child_writes = NULL;
+static struct write_call *child_writes = NULL;
static unsigned int child_writes_num = 0;
static pid_t lock_owner;
static bool read_write_info(int fd)
{
- struct write_info_hdr hdr;
-
- if (!read_all(fd, &hdr, sizeof(hdr)))
- return false;
+ struct write_call *w;
+ char *buf;
+ /* We don't need all of this, but it's simple. */
child_writes = realloc(child_writes,
(child_writes_num+1) * sizeof(child_writes[0]));
- child_writes[child_writes_num].hdr = hdr;
- child_writes[child_writes_num].data = malloc(hdr.len);
- if (!read_all(fd, child_writes[child_writes_num].data, hdr.len))
+ w = &child_writes[child_writes_num];
+ if (!read_all(fd, w, sizeof(*w)))
+ return false;
+
+ w->buf = buf = malloc(w->count);
+ if (!read_all(fd, buf, w->count))
return false;
child_writes_num++;
err(1, "Writing trace.");
}
+struct saved_file {
+ struct saved_file *next;
+ int fd;
+ void *contents;
+ off_t off, len;
+};
+
+static struct saved_file *save_file(struct saved_file *next, int fd)
+{
+ struct saved_file *s = malloc(sizeof(*s));
+
+ s->next = next;
+ s->fd = fd;
+ s->off = lseek(fd, 0, SEEK_CUR);
+ /* Special file? Erk... */
+ assert(s->off != -1);
+ s->len = lseek(fd, 0, SEEK_END);
+ lseek(fd, 0, SEEK_SET);
+ s->contents = malloc(s->len);
+ read(fd, s->contents, s->len);
+ lseek(fd, s->off, SEEK_SET);
+ return s;
+}
+
+/* We have little choice but to save and restore open files: mmap means we
+ * can really intercept changes in the child.
+ *
+ * We could do non-mmap'ed files on demand, however. */
+static struct saved_file *save_files(void)
+{
+ struct saved_file *files = NULL;
+ int i;
+
+ /* Figure out the set of live fds. */
+ for (i = history_num - 2; i >= 0; i--) {
+ if (history[i].type == FAILTEST_OPEN) {
+ int fd = history[i].u.open.ret;
+ /* Only do successful, writable fds. */
+ if (fd < 0)
+ continue;
+
+ /* If it was closed, cleanup == NULL. */
+ if (!history[i].cleanup)
+ continue;
+
+ if ((history[i].u.open.flags & O_RDWR) == O_RDWR) {
+ files = save_file(files, fd);
+ } else if ((history[i].u.open.flags & O_WRONLY)
+ == O_WRONLY) {
+ /* FIXME: Handle O_WRONLY. Open with O_RDWR? */
+ abort();
+ }
+ }
+ }
+
+ return files;
+}
+
+static void restore_files(struct saved_file *s)
+{
+ while (s) {
+ struct saved_file *next = s->next;
+
+ lseek(s->fd, 0, SEEK_SET);
+ write(s->fd, s->contents, s->len);
+ ftruncate(s->fd, s->len);
+ free(s->contents);
+ lseek(s->fd, s->off, SEEK_SET);
+ free(s);
+ s = next;
+ }
+}
+
static bool should_fail(struct failtest_call *call)
{
int status;
enum info_type type = UNEXPECTED;
char *out = NULL;
size_t outlen = 0;
+ struct saved_file *files;
if (call == &unrecorded_call)
return false;
}
}
+ /* Attach debugger if they asked for it. */
+ if (debugpath && history_num == strlen(debugpath)) {
+ unsigned int i;
+
+ for (i = 0; i < history_num; i++) {
+ char c = info_to_arg[history[i].type];
+ if (history[i].fail)
+ c = toupper(c);
+ if (c != debugpath[i])
+ break;
+ }
+ if (i == history_num) {
+ char str[80];
+
+ /* Don't timeout. */
+ signal(SIGUSR1, SIG_IGN);
+ sprintf(str, "xterm -e gdb /proc/%d/exe %d &",
+ getpid(), getpid());
+ system(str);
+ sleep(5);
+ }
+ }
+
if (!failtest_hook(history, history_num)) {
call->fail = false;
return false;
}
+ files = save_files();
+
/* We're going to fail in the child. */
call->fail = true;
if (pipe(control) != 0 || pipe(output) != 0)
close(output[0]);
close(control[0]);
waitpid(child, &status, 0);
- if (!WIFEXITED(status))
- child_fail(out, outlen, "Killed by signal %u: ",
- WTERMSIG(status));
+ if (!WIFEXITED(status)) {
+ if (WTERMSIG(status) == SIGUSR1)
+ child_fail(out, outlen, "Timed out");
+ else
+ child_fail(out, outlen, "Killed by signal %u: ",
+ WTERMSIG(status));
+ }
/* Child printed failure already, just pass up exit code. */
if (type == FAILURE) {
fprintf(stderr, "%.*s", (int)outlen, out);
free(out);
signal(SIGUSR1, SIG_DFL);
+ restore_files(files);
+
/* We continue onwards without failing. */
call->fail = false;
return false;
/* Avoid memory leak! */
if (p == &unrecorded_call)
free((char *)call.pathname);
- if (should_fail(p)) {
+ p->u.open.ret = open(pathname, call.flags, call.mode);
+
+ if (!failpath && p->u.open.ret == -1) {
+ p->fail = false;
+ p->error = errno;
+ } else if (should_fail(p)) {
+ close(p->u.open.ret);
p->u.open.ret = -1;
/* FIXME: Play with error codes? */
p->error = EACCES;
} else {
- p->u.open.ret = open(pathname, call.flags, call.mode);
set_cleanup(p, cleanup_open, struct open_call);
- p->u.open.dup_fd = p->u.open.ret;
}
errno = p->error;
return p->u.open.ret;
return p->u.pipe.ret;
}
-static void cleanup_read(struct read_call *call)
-{
- lseek(call->fd, call->off, SEEK_SET);
-}
-
ssize_t failtest_pread(int fd, void *buf, size_t count, off_t off,
const char *file, unsigned line)
{
p->error = EIO;
} else {
p->u.read.ret = pread(fd, buf, count, off);
- set_cleanup(p, cleanup_read, struct read_call);
}
errno = p->error;
return p->u.read.ret;
}
-static struct write_info *new_write(void)
-{
- writes = realloc(writes, (writes_num + 1) * sizeof(*writes));
- return &writes[writes_num++];
-}
-
-static void cleanup_write(struct write_call *call)
-{
- lseek(call->dup_fd, call->off, SEEK_SET);
- write(call->dup_fd, call->saved_contents, call->saved_len);
- lseek(call->dup_fd, call->off, SEEK_SET);
- ftruncate(call->dup_fd, call->old_filelen);
- free(call->saved_contents);
-}
-
ssize_t failtest_pwrite(int fd, const void *buf, size_t count, off_t off,
const char *file, unsigned line)
{
struct failtest_call *p;
struct write_call call;
- call.fd = call.dup_fd = fd;
+ call.fd = fd;
call.buf = buf;
call.count = count;
call.off = off;
p = add_history(FAILTEST_WRITE, file, line, &call);
- /* Save old contents if we can */
- if (p->u.write.off != -1) {
- ssize_t ret;
- p->u.write.old_filelen = lseek(fd, 0, SEEK_END);
-
- /* Write past end of file? Nothing to save.*/
- if (p->u.write.old_filelen <= p->u.write.off)
- p->u.write.saved_len = 0;
- /* Write which goes over end of file? Partial save. */
- else if (p->u.write.off + count > p->u.write.old_filelen)
- p->u.write.saved_len = p->u.write.old_filelen
- - p->u.write.off;
- /* Full save. */
- else
- p->u.write.saved_len = count;
-
- p->u.write.saved_contents = malloc(p->u.write.saved_len);
- lseek(fd, p->u.write.off, SEEK_SET);
- ret = read(fd, p->u.write.saved_contents, p->u.write.saved_len);
- if (ret != p->u.write.saved_len)
- err(1, "Expected %i bytes, got %i",
- (int)p->u.write.saved_len, (int)ret);
- lseek(fd, p->u.write.off, SEEK_SET);
- set_cleanup(p, cleanup_write, struct write_call);
- }
-
- /* If we're a child, tell parent about write. */
- if (control_fd != -1) {
- struct write_info *winfo = new_write();
+ /* If we're a child, we need to make sure we write the same thing
+ * to non-files as the parent does, so tell it. */
+ if (control_fd != -1 && off == (off_t)-1) {
enum info_type type = WRITE;
- winfo->hdr.len = count;
- winfo->hdr.fd = fd;
- winfo->data = malloc(count);
- memcpy(winfo->data, buf, count);
- winfo->hdr.offset = off;
write_all(control_fd, &type, sizeof(type));
- write_all(control_fd, &winfo->hdr, sizeof(winfo->hdr));
- write_all(control_fd, winfo->data, count);
+ write_all(control_fd, &p->u.write, sizeof(p->u.write));
+ write_all(control_fd, buf, count);
}
/* FIXME: Try partial write returns. */
p->error = EIO;
} else {
/* FIXME: We assume same write order in parent and child */
- if (child_writes_num != 0) {
- if (child_writes[0].hdr.fd != fd)
+ if (off == (off_t)-1 && child_writes_num != 0) {
+ if (child_writes[0].fd != fd)
errx(1, "Child wrote to fd %u, not %u?",
- child_writes[0].hdr.fd, fd);
- if (child_writes[0].hdr.offset != p->u.write.off)
+ child_writes[0].fd, fd);
+ if (child_writes[0].off != p->u.write.off)
errx(1, "Child wrote to offset %zu, not %zu?",
- (size_t)child_writes[0].hdr.offset,
+ (size_t)child_writes[0].off,
(size_t)p->u.write.off);
- if (child_writes[0].hdr.len != count)
+ if (child_writes[0].count != count)
errx(1, "Child wrote length %zu, not %zu?",
- child_writes[0].hdr.len, count);
- if (memcmp(child_writes[0].data, buf, count)) {
+ child_writes[0].count, count);
+ if (memcmp(child_writes[0].buf, buf, count)) {
child_fail(NULL, 0,
"Child wrote differently to"
" fd %u than we did!\n", fd);
}
- free(child_writes[0].data);
+ free((char *)child_writes[0].buf);
child_writes_num--;
memmove(&child_writes[0], &child_writes[1],
sizeof(child_writes[0]) * child_writes_num);
return locks;
}
-/* We only trap this so we can dup fds in case we need to restore. */
+/* We trap this so we can record it: we don't fail it. */
int failtest_close(int fd)
{
- int new_fd = -1, i;
+ int i;
if (fd < 0)
return close(fd);
- /* Trace history to find source of fd, and if we need to cleanup writes. */
+ /* Trace history to find source of fd. */
for (i = history_num-1; i >= 0; i--) {
switch (history[i].type) {
- case FAILTEST_WRITE:
- if (history[i].u.write.fd != fd)
- break;
- if (!history[i].cleanup)
- break;
- /* We need to save fd so we can restore file. */
- if (new_fd == -1)
- new_fd = dup(fd);
- history[i].u.write.dup_fd = new_fd;
- break;
- case FAILTEST_READ:
- /* We don't need to cleanup reads on closed fds. */
- if (history[i].u.read.fd != fd)
- break;
- history[i].cleanup = NULL;
- break;
case FAILTEST_PIPE:
- /* From a pipe? We don't ever restore pipes... */
+ /* From a pipe? */
if (history[i].u.pipe.fds[0] == fd) {
- assert(new_fd == -1);
+ assert(!history[i].u.pipe.closed[0]);
history[i].u.pipe.closed[0] = true;
+ if (history[i].u.pipe.closed[1])
+ history[i].cleanup = NULL;
goto out;
}
if (history[i].u.pipe.fds[1] == fd) {
- assert(new_fd == -1);
+ assert(!history[i].u.pipe.closed[1]);
history[i].u.pipe.closed[1] = true;
+ if (history[i].u.pipe.closed[0])
+ history[i].cleanup = NULL;
goto out;
}
break;
case FAILTEST_OPEN:
if (history[i].u.open.ret == fd) {
- history[i].u.open.dup_fd = new_fd;
+ assert((void *)history[i].cleanup
+ == (void *)cleanup_open);
+ history[i].cleanup = NULL;
goto out;
}
break;
} else if (strcmp(argv[i], "--tracepath") == 0) {
tracefd = dup(STDERR_FILENO);
failtest_timeout_ms = -1;
+ } else if (!strncmp(argv[i], "--debugpath=",
+ strlen("--debugpath="))) {
+ debugpath = argv[i] + strlen("--debugpath=");
}
}
gettimeofday(&start, NULL);
{
unsigned int i;
- for (i = 0; i < writes_num; i++) {
- free(writes[i].data);
- }
- free(writes);
-
/* We don't do this in cleanup: needed even for failed opens. */
for (i = 0; i < history_num; i++) {
if (history[i].type == FAILTEST_OPEN)
{
int i;
- if (control_fd == -1) {
- free_everything();
- exit(status);
- }
-
if (failtest_exit_check) {
if (!failtest_exit_check(history, history_num))
child_fail(NULL, 0, "failtest_exit_check failed\n");
}
+ if (control_fd == -1) {
+ free_everything();
+ exit(status);
+ }
+
/* Cleanup everything, in reverse order. */
for (i = history_num - 1; i >= 0; i--)
if (history[i].cleanup)