#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
-#include <fcntl.h>
+#include <sys/time.h>
+#include <assert.h>
#include <ccan/read_write_all/read_write_all.h>
#include <ccan/failtest/failtest_proto.h>
#include <ccan/failtest/failtest.h>
+#include <ccan/build_assert/build_assert.h>
bool (*failtest_hook)(struct failtest_call *history, unsigned num)
= failtest_default_hook;
+static int tracefd = -1;
+
unsigned int failtest_timeout_ms = 20000;
const char *failpath;
enum info_type {
WRITE,
+ RELEASE_LOCKS,
FAILURE,
SUCCESS,
UNEXPECTED
char *olddata;
};
+struct lock_info {
+ int fd;
+ /* end is inclusive: you can't have a 0-byte lock. */
+ off_t start, end;
+ int type;
+};
+
bool (*failtest_exit_check)(struct failtest_call *history, unsigned num);
static struct failtest_call *history = NULL;
static unsigned int history_num = 0;
static int control_fd = -1;
+static struct timeval start;
static struct write_info *writes = NULL;
static unsigned int writes_num = 0;
static struct fd_orig *fd_orig = NULL;
static unsigned int fd_orig_num = 0;
-static const char info_to_arg[] = "mceoprw";
+static pid_t lock_owner;
+static struct lock_info *locks = NULL;
+static unsigned int lock_num = 0;
+
+static const char info_to_arg[] = "mceoprwf";
/* Dummy call used for failtest_undo wrappers. */
static struct failtest_call unrecorded_call;
return true;
}
-static void print_reproduce(void)
+static char *failpath_string(void)
{
unsigned int i;
+ char *ret = malloc(history_num + 1);
- printf("To reproduce: --failpath=");
for (i = 0; i < history_num; i++) {
+ ret[i] = info_to_arg[history[i].type];
if (history[i].fail)
- printf("%c", toupper(info_to_arg[history[i].type]));
- else
- printf("%c", info_to_arg[history[i].type]);
+ ret[i] = toupper(ret[i]);
}
- printf("\n");
+ ret[i] = '\0';
+ return ret;
}
static void tell_parent(enum info_type type)
static void child_fail(const char *out, size_t outlen, const char *fmt, ...)
{
va_list ap;
+ char *path = failpath_string();
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
fprintf(stderr, "%.*s", (int)outlen, out);
- print_reproduce();
+ printf("To reproduce: --failpath=%s\n", path);
+ free(path);
tell_parent(FAILURE);
exit(1);
}
kill(child, signal);
}
+static void release_locks(void)
+{
+ /* Locks were never acquired/reacquired? */
+ if (lock_owner == 0)
+ return;
+
+ /* We own them? Release them all. */
+ if (lock_owner == getpid()) {
+ unsigned int i;
+ struct flock fl;
+ fl.l_type = F_UNLCK;
+ fl.l_whence = SEEK_SET;
+ fl.l_start = 0;
+ fl.l_len = 0;
+
+ for (i = 0; i < lock_num; i++)
+ fcntl(locks[i].fd, F_SETLK, &fl);
+ } else {
+ /* Our parent must have them; pass request up. */
+ enum info_type type = RELEASE_LOCKS;
+ assert(control_fd != -1);
+ write_all(control_fd, &type, sizeof(type));
+ }
+ lock_owner = 0;
+}
+
+/* off_t is a signed type. Getting its max is non-trivial. */
+static off_t off_max(void)
+{
+ BUILD_ASSERT(sizeof(off_t) == 4 || sizeof(off_t) == 8);
+ if (sizeof(off_t) == 4)
+ return (off_t)0x7FFFFFF;
+ else
+ return (off_t)0x7FFFFFFFFFFFFFFULL;
+}
+
+static void get_locks(void)
+{
+ unsigned int i;
+ struct flock fl;
+
+ if (lock_owner == getpid())
+ return;
+
+ if (lock_owner != 0) {
+ enum info_type type = RELEASE_LOCKS;
+ assert(control_fd != -1);
+ write_all(control_fd, &type, sizeof(type));
+ }
+
+ fl.l_whence = SEEK_SET;
+
+ for (i = 0; i < lock_num; i++) {
+ fl.l_type = locks[i].type;
+ fl.l_start = locks[i].start;
+ if (locks[i].end == off_max())
+ fl.l_len = 0;
+ else
+ fl.l_len = locks[i].end - locks[i].start + 1;
+
+ if (fcntl(locks[i].fd, F_SETLKW, &fl) != 0)
+ abort();
+ }
+ lock_owner = getpid();
+}
+
+static void trace_str(const char *str)
+{
+ ssize_t ret;
+
+ while ((ret = write(tracefd, str, strlen(str))) <= 0) {
+ str += ret;
+ if (!*str)
+ return;
+ }
+ err(1, "Writing trace.");
+}
+
static bool should_fail(struct failtest_call *call)
{
int status;
if (tolower(*failpath) != info_to_arg[call->type])
errx(1, "Failpath expected '%c' got '%c'\n",
info_to_arg[call->type], *failpath);
- return isupper(*(failpath++));
+ call->fail = isupper(*(failpath++));
+ return call->fail;
}
if (!failtest_hook(history, history_num)) {
err(1, "forking failed");
if (child == 0) {
+ if (tracefd != -1) {
+ struct timeval now;
+ char str[50], *p;
+ gettimeofday(&now, NULL);
+ if (now.tv_usec < start.tv_usec) {
+ now.tv_sec--;
+ now.tv_usec += 1000000;
+ }
+ now.tv_usec -= start.tv_usec;
+ now.tv_sec -= start.tv_sec;
+ sprintf(str, "%u (%u.%02u): ", getpid(),
+ (int)now.tv_sec, (int)now.tv_usec / 10000);
+ trace_str(str);
+ p = failpath_string();
+ trace_str(p);
+ free(p);
+ trace_str("(");
+ p = strchr(history[history_num-1].file, '/');
+ if (p)
+ trace_str(p+1);
+ else
+ trace_str(history[history_num-1].file);
+ sprintf(str, ":%u)\n", history[history_num-1].line);
+ trace_str(str);
+ }
close(control[0]);
close(output[0]);
dup2(output[1], STDOUT_FILENO);
if (type == WRITE) {
if (!read_write_info(control[0]))
break;
+ } else if (type == RELEASE_LOCKS) {
+ release_locks();
+ /* FIXME: Tell them we're done... */
}
}
} else if (pfd[0].revents & POLLHUP) {
return p->u.realloc.ret;
}
-int failtest_open(const char *pathname, int flags,
+int failtest_open(const char *pathname,
const char *file, unsigned line, ...)
{
struct failtest_call *p;
struct open_call call;
+ va_list ap;
call.pathname = strdup(pathname);
- call.flags = flags;
- if (flags & O_CREAT) {
- va_list ap;
- va_start(ap, line);
+ va_start(ap, line);
+ call.flags = va_arg(ap, int);
+ if (call.flags & O_CREAT) {
call.mode = va_arg(ap, mode_t);
va_end(ap);
}
/* FIXME: Play with error codes? */
p->error = EACCES;
} else {
- p->u.open.ret = open(pathname, flags, call.mode);
+ p->u.open.ret = open(pathname, call.flags, call.mode);
}
errno = p->error;
return p->u.open.ret;
return p->u.pipe.ret;
}
-ssize_t failtest_read(int fd, void *buf, size_t count,
- const char *file, unsigned line)
+ssize_t failtest_pread(int fd, void *buf, size_t count, off_t off,
+ const char *file, unsigned line)
{
struct failtest_call *p;
struct read_call call;
call.fd = fd;
call.buf = buf;
call.count = count;
+ call.off = off;
p = add_history(FAILTEST_READ, file, line, &call);
/* This is going to change seek offset, so save it. */
p->u.read.ret = -1;
p->error = EIO;
} else {
- p->u.read.ret = read(fd, buf, count);
+ p->u.read.ret = pread(fd, buf, count, off);
}
errno = p->error;
return p->u.read.ret;
return &writes[writes_num++];
}
-ssize_t failtest_write(int fd, const void *buf, size_t count,
- const char *file, unsigned line)
+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 = fd;
call.buf = buf;
call.count = count;
+ call.off = off;
p = add_history(FAILTEST_WRITE, file, line, &call);
offset = lseek(fd, 0, SEEK_CUR);
return p->u.write.ret;
}
}
- p->u.write.ret = write(fd, buf, count);
+ p->u.write.ret = pwrite(fd, buf, count, off);
}
errno = p->error;
return p->u.write.ret;
}
+ssize_t failtest_read(int fd, void *buf, size_t count,
+ const char *file, unsigned line)
+{
+ return failtest_pread(fd, buf, count, lseek(fd, 0, SEEK_CUR),
+ file, line);
+}
+
+ssize_t failtest_write(int fd, const void *buf, size_t count,
+ const char *file, unsigned line)
+{
+ return failtest_pwrite(fd, buf, count, lseek(fd, 0, SEEK_CUR),
+ file, line);
+}
+
+static struct lock_info *WARN_UNUSED_RESULT
+add_lock(struct lock_info *locks, int fd, off_t start, off_t end, int type)
+{
+ unsigned int i;
+ struct lock_info *l;
+
+ for (i = 0; i < lock_num; i++) {
+ l = &locks[i];
+
+ if (l->fd != fd)
+ continue;
+ /* Four cases we care about:
+ * Start overlap:
+ * l = | |
+ * new = | |
+ * Mid overlap:
+ * l = | |
+ * new = | |
+ * End overlap:
+ * l = | |
+ * new = | |
+ * Total overlap:
+ * l = | |
+ * new = | |
+ */
+ if (start > l->start && end < l->end) {
+ /* Mid overlap: trim entry, add new one. */
+ off_t new_start, new_end;
+ new_start = end + 1;
+ new_end = l->end;
+ l->end = start - 1;
+ locks = add_lock(locks,
+ fd, new_start, new_end, l->type);
+ l = &locks[i];
+ } else if (start <= l->start && end >= l->end) {
+ /* Total overlap: eliminate entry. */
+ l->end = 0;
+ l->start = 1;
+ } else if (end >= l->start && end < l->end) {
+ /* Start overlap: trim entry. */
+ l->start = end + 1;
+ } else if (start > l->start && start <= l->end) {
+ /* End overlap: trim entry. */
+ l->end = start-1;
+ }
+ /* Nothing left? Remove it. */
+ if (l->end < l->start) {
+ memmove(l, l + 1, (--lock_num - i) * sizeof(l[0]));
+ i--;
+ }
+ }
+
+ if (type != F_UNLCK) {
+ locks = realloc(locks, (lock_num + 1) * sizeof(*locks));
+ l = &locks[lock_num++];
+ l->fd = fd;
+ l->start = start;
+ l->end = end;
+ l->type = type;
+ }
+ return locks;
+}
+
/* We only trap this so we can dup fds in case we need to restore. */
int failtest_close(int fd)
{
if (writes[i].hdr.fd == fd)
writes[i].hdr.fd = newfd;
}
+
+ locks = add_lock(locks, fd, 0, off_max(), F_UNLCK);
return close(fd);
}
+/* Zero length means "to end of file" */
+static off_t end_of(off_t start, off_t len)
+{
+ if (len == 0)
+ return off_max();
+ return start + len - 1;
+}
+
+/* FIXME: This only handles locks, really. */
+int failtest_fcntl(int fd, const char *file, unsigned line, int cmd, ...)
+{
+ struct failtest_call *p;
+ struct fcntl_call call;
+ va_list ap;
+
+ call.fd = fd;
+ call.cmd = cmd;
+
+ /* Argument extraction. */
+ switch (cmd) {
+ case F_SETFL:
+ case F_SETFD:
+ va_start(ap, cmd);
+ call.arg.l = va_arg(ap, long);
+ va_end(ap);
+ return fcntl(fd, cmd, call.arg.l);
+ case F_GETFD:
+ case F_GETFL:
+ return fcntl(fd, cmd);
+ case F_GETLK:
+ get_locks();
+ va_start(ap, cmd);
+ call.arg.fl = *va_arg(ap, struct flock *);
+ va_end(ap);
+ return fcntl(fd, cmd, &call.arg.fl);
+ case F_SETLK:
+ case F_SETLKW:
+ va_start(ap, cmd);
+ call.arg.fl = *va_arg(ap, struct flock *);
+ va_end(ap);
+ break;
+ default:
+ /* This means you need to implement it here. */
+ err(1, "failtest: unknown fcntl %u", cmd);
+ }
+
+ p = add_history(FAILTEST_FCNTL, file, line, &call);
+ get_locks();
+
+ if (should_fail(p)) {
+ p->u.fcntl.ret = -1;
+ if (p->u.fcntl.cmd == F_SETLK)
+ p->error = EAGAIN;
+ else
+ p->error = EDEADLK;
+ } else {
+ p->u.fcntl.ret = fcntl(p->u.fcntl.fd, p->u.fcntl.cmd,
+ &p->u.fcntl.arg.fl);
+ if (p->u.fcntl.ret == -1)
+ p->error = errno;
+ else {
+ /* We don't handle anything else yet. */
+ assert(p->u.fcntl.arg.fl.l_whence == SEEK_SET);
+ locks = add_lock(locks,
+ p->u.fcntl.fd,
+ p->u.fcntl.arg.fl.l_start,
+ end_of(p->u.fcntl.arg.fl.l_start,
+ p->u.fcntl.arg.fl.l_len),
+ p->u.fcntl.arg.fl.l_type);
+ }
+ }
+ errno = p->error;
+ return p->u.fcntl.ret;
+}
+
void failtest_init(int argc, char *argv[])
{
- if (argc == 2
- && strncmp(argv[1], "--failpath=", strlen("--failpath=")) == 0) {
- failpath = argv[1] + strlen("--failpath=");
+ unsigned int i;
+
+ for (i = 1; i < argc; i++) {
+ if (!strncmp(argv[i], "--failpath=", strlen("--failpath="))) {
+ failpath = argv[i] + strlen("--failpath=");
+ } else if (strcmp(argv[i], "--tracepath") == 0) {
+ tracefd = dup(STDERR_FILENO);
+ failtest_timeout_ms = -1;
+ }
+ }
+ gettimeofday(&start, NULL);
+}
+
+/* Free up memory, so valgrind doesn't report leaks. */
+static void free_everything(void)
+{
+ unsigned int i;
+
+ for (i = 0; i < writes_num; i++) {
+ free(writes[i].data);
+ if (writes[i].hdr.offset != (off_t)-1)
+ free(writes[i].olddata);
}
+ free(writes);
+ free(fd_orig);
+ for (i = 0; i < history_num; i++) {
+ if (history[i].type == FAILTEST_OPEN)
+ free((char *)history[i].u.open.pathname);
+ }
+ free(history);
}
void failtest_exit(int status)
{
unsigned int i;
- if (control_fd == -1)
+ if (control_fd == -1) {
+ free_everything();
exit(status);
+ }
if (failtest_exit_check) {
if (!failtest_exit_check(history, history_num))
close(fd_orig[i].fd);
}
+ free_everything();
tell_parent(SUCCESS);
exit(0);
}
projects / ccan / blobdiff