From: Rusty Russell Date: Tue, 15 Feb 2011 13:01:29 +0000 (+1030) Subject: failtest: hook can return FAIL_PROBE X-Git-Url: https://git.ozlabs.org/?p=ccan;a=commitdiff_plain;h=c9f915e02c760caffe75da7f9a6a9a1de1bf1747 failtest: hook can return FAIL_PROBE tdb2 has various places where it recovers from failure (eg. falling back when it can't open /dev/urandom, or allocation for error logging). We want to test those paths, but doing so thoroughly causes cominatorial explosion. Add FAIL_PROBE for such cases: in this case it goes only 3 more calls deep. --- diff --git a/ccan/failtest/failtest.c b/ccan/failtest/failtest.c index 9ecc535a..9972db3c 100644 --- a/ccan/failtest/failtest.c +++ b/ccan/failtest/failtest.c @@ -17,8 +17,7 @@ #include #include -bool (*failtest_hook)(struct failtest_call *history, unsigned num) -= failtest_default_hook; +enum failtest_result (*failtest_hook)(struct failtest_call *, unsigned); static int tracefd = -1; @@ -48,6 +47,7 @@ static struct failtest_call *history = NULL; static unsigned int history_num = 0; static int control_fd = -1; static struct timeval start; +static unsigned int probe_count = 0; static struct write_call *child_writes = NULL; static unsigned int child_writes_num = 0; @@ -86,11 +86,6 @@ static struct failtest_call *add_history_(enum failtest_call_type type, #define set_cleanup(call, clean, type) \ (call)->cleanup = (void *)((void)sizeof(clean((type *)NULL)), (clean)) -bool failtest_default_hook(struct failtest_call *history, unsigned num) -{ - return true; -} - static bool read_write_info(int fd) { struct write_call *w; @@ -305,6 +300,40 @@ static void restore_files(struct saved_file *s) } } +/* Free up memory, so valgrind doesn't report leaks. */ +static void free_everything(void) +{ + unsigned int i; + + /* 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) + free((char *)history[i].u.open.pathname); + } + free(history); +} + +static NORETURN void failtest_cleanup(bool forced_cleanup, int status) +{ + int i; + + if (forced_cleanup) + history_num--; + + /* Cleanup everything, in reverse order. */ + for (i = history_num - 1; i >= 0; i--) + if (history[i].cleanup) + history[i].cleanup(&history[i].u); + + free_everything(); + + if (control_fd == -1) + exit(status); + + tell_parent(SUCCESS); + exit(0); +} + static bool should_fail(struct failtest_call *call) { int status; @@ -314,6 +343,10 @@ static bool should_fail(struct failtest_call *call) size_t outlen = 0; struct saved_file *files; + /* Are we probing? */ + if (probe_count && --probe_count == 0) + failtest_cleanup(true, 0); + if (call == &unrecorded_call) return false; @@ -353,9 +386,24 @@ static bool should_fail(struct failtest_call *call) } } - if (!failtest_hook(history, history_num)) { - call->fail = false; - return false; + if (failtest_hook) { + switch (failtest_hook(history, history_num)) { + case FAIL_OK: + break; + case FAIL_DONT_FAIL: + call->fail = false; + return false; + case FAIL_PROBE: + /* Already down probe path? Stop now. */ + if (probe_count) + failtest_cleanup(true, 0); + /* FIXME: We should run *parent* and run probe until + * calls match up again. */ + probe_count = 3; + break; + default: + abort(); + } } files = save_files(); @@ -974,39 +1022,12 @@ void failtest_init(int argc, char *argv[]) gettimeofday(&start, NULL); } -/* Free up memory, so valgrind doesn't report leaks. */ -static void free_everything(void) -{ - unsigned int i; - - /* 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) - free((char *)history[i].u.open.pathname); - } - free(history); -} - void failtest_exit(int status) { - int i; - 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) - history[i].cleanup(&history[i].u); - - free_everything(); - tell_parent(SUCCESS); - exit(0); + failtest_cleanup(false, status); } diff --git a/ccan/failtest/failtest.h b/ccan/failtest/failtest.h index ec238af0..1aa92181 100644 --- a/ccan/failtest/failtest.h +++ b/ccan/failtest/failtest.h @@ -143,30 +143,42 @@ struct failtest_call { } u; }; +enum failtest_result { + /* Yes try failing this call. */ + FAIL_OK, + /* No, don't try failing this call. */ + FAIL_DONT_FAIL, + /* Try failing this call but don't go too far down that path. */ + FAIL_PROBE, +}; + /** * failtest_hook - whether a certain call should fail or not. * @history: the ordered history of all failtest calls. * @num: the number of elements in @history (greater than 0) * * The default value of this hook is failtest_default_hook(), which returns - * true (ie. yes, fail the call). + * FAIL_OK (ie. yes, fail the call). * * You can override it, and avoid failing certain calls. The parameters * of the call (but not the return value(s)) will be filled in for the last * call. * * Example: - * static bool dont_fail_allocations(struct failtest_call *history, - * unsigned num) + * static enum failtest_result dont_fail_alloc(struct failtest_call *hist, + * unsigned num) * { - * return history[num-1].type != FAILTEST_MALLOC - * && history[num-1].type != FAILTEST_CALLOC - * && history[num-1].type != FAILTEST_REALLOC; + * if (hist[num-1].type == FAILTEST_MALLOC + * || hist[num-1].type == FAILTEST_CALLOC + * || hist[num-1].type == FAILTEST_REALLOC) + * return FAIL_DONT_FAIL; + * return FAIL_OK; * } * ... - * failtest_hook = dont_fail_allocations; + * failtest_hook = dont_fail_alloc; */ -extern bool (*failtest_hook)(struct failtest_call *history, unsigned num); +extern enum failtest_result +(*failtest_hook)(struct failtest_call *history, unsigned num); /** * failtest_exit_check - hook for additional checks on a failed child. @@ -183,9 +195,6 @@ extern bool (*failtest_hook)(struct failtest_call *history, unsigned num); extern bool (*failtest_exit_check)(struct failtest_call *history, unsigned num); -/* This usually fails the call. */ -bool failtest_default_hook(struct failtest_call *history, unsigned num); - /** * failtest_timeout_ms - how long to wait before killing child. * diff --git a/ccan/failtest/test/run-locking.c b/ccan/failtest/test/run-locking.c index b25cfab9..6ebcd6ea 100644 --- a/ccan/failtest/test/run-locking.c +++ b/ccan/failtest/test/run-locking.c @@ -10,9 +10,10 @@ #define SIZE 8 /* We don't want to fork and fail; we're just testing lock recording. */ -static bool dont_fail(struct failtest_call *history, unsigned num) +static enum failtest_result dont_fail(struct failtest_call *history, + unsigned num) { - return false; + return FAIL_DONT_FAIL; } static bool place_lock(int fd, char lockarr[], unsigned pos, unsigned size,