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;
return false;
}
+ files = save_files();
+
/* We're going to fail in the child. */
call->fail = true;
if (pipe(control) != 0 || pipe(output) != 0)
free(out);
signal(SIGUSR1, SIG_DFL);
+ restore_files(files);
+
/* We continue onwards without failing. */
call->fail = false;
return false;
} 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 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) {
+ /* 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;
write_all(control_fd, &type, sizeof(type));
p->error = EIO;
} else {
/* FIXME: We assume same write order in parent and child */
- if (child_writes_num != 0) {
+ 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].fd, fd);
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;
projects / ccan / blobdiff