failtest: use a linked list for history, not an array.
authorRusty Russell <rusty@rustcorp.com.au>
Tue, 29 Nov 2011 22:34:11 +0000 (09:04 +1030)
committerRusty Russell <rusty@rustcorp.com.au>
Tue, 29 Nov 2011 22:34:11 +0000 (09:04 +1030)
This avoids a silly realloc, but more importantly it gets us closer to
being runtime extensible, as each history element can be a different
size.

ccan/failtest/_info
ccan/failtest/failtest.c
ccan/failtest/failtest.h
ccan/failtest/test/run-history.c
ccan/failtest/test/run-locking.c
ccan/tdb2/test/failtest_helper.c
ccan/tdb2/test/failtest_helper.h

index a9189a238fcdb363e3882f93d3333e4200438bb5..d8b2a252b779a21451ba5f6c259e4e6dfdc21c36 100644 (file)
@@ -61,10 +61,12 @@ int main(int argc, char *argv[])
                return 1;
 
        if (strcmp(argv[1], "depends") == 0) {
+               printf("ccan/build_assert\n");
                printf("ccan/compiler\n");
                printf("ccan/read_write_all\n");
-               printf("ccan/build_assert\n");
+               printf("ccan/str\n");
                printf("ccan/time\n");
+               printf("ccan/tlist\n");
                return 0;
        }
 
index c95a94f8d0ce4968dfe9266a47a68343c96b2fa9..f59ed03acf4abc70f48c8779fabf6684ab724444 100644 (file)
@@ -19,8 +19,9 @@
 #include <ccan/read_write_all/read_write_all.h>
 #include <ccan/failtest/failtest_proto.h>
 #include <ccan/build_assert/build_assert.h>
+#include <ccan/str/str.h>
 
-enum failtest_result (*failtest_hook)(struct failtest_call *, unsigned);
+enum failtest_result (*failtest_hook)(struct tlist_calls *);
 
 static int tracefd = -1;
 
@@ -44,10 +45,9 @@ struct lock_info {
        int type;
 };
 
-bool (*failtest_exit_check)(struct failtest_call *history, unsigned num);
+bool (*failtest_exit_check)(struct tlist_calls *history);
 
-static struct failtest_call *history = NULL;
-static unsigned int history_num = 0;
+static struct tlist_calls history = TLIST_INIT(history);
 static int control_fd = -1;
 static struct timeval start;
 static unsigned int probe_count = 0;
@@ -72,17 +72,20 @@ static struct failtest_call *add_history_(enum failtest_call_type type,
                                          const void *elem,
                                          size_t elem_size)
 {
+       struct failtest_call *call;
+
        /* NULL file is how we suppress failure. */
        if (!file)
                return &unrecorded_call;
 
-       history = realloc(history, (history_num + 1) * sizeof(*history));
-       history[history_num].type = type;
-       history[history_num].file = file;
-       history[history_num].line = line;
-       history[history_num].cleanup = NULL;
-       memcpy(&history[history_num].u, elem, elem_size);
-       return &history[history_num++];
+       call = malloc(sizeof *call);
+       call->type = type;
+       call->file = file;
+       call->line = line;
+       call->cleanup = NULL;
+       memcpy(&call->u, elem, elem_size);
+       tlist_add_tail(&history, call, list);
+       return call;
 }
 
 #define add_history(type, file, line, elem) \
@@ -114,15 +117,18 @@ static bool read_write_info(int fd)
 
 static char *failpath_string(void)
 {
-       unsigned int i;
-       char *ret = malloc(history_num + 1);
-
-       for (i = 0; i < history_num; i++) {
-               ret[i] = info_to_arg[history[i].type];
-               if (history[i].fail)
-                       ret[i] = toupper(ret[i]);
+       struct failtest_call *i;
+       char *ret = strdup("");
+       unsigned len = 0;
+
+       /* Inefficient, but who cares? */
+       tlist_for_each(&history, i, list) {
+               ret = realloc(ret, len + 2);
+               ret[len] = info_to_arg[i->type];
+               if (i->fail)
+                       ret[len] = toupper(ret[len]);
+               ret[++len] = '\0';
        }
-       ret[i] = '\0';
        return ret;
 }
 
@@ -265,23 +271,23 @@ static struct saved_file *save_file(struct saved_file *next, int fd)
 static struct saved_file *save_files(void)
 {
        struct saved_file *files = NULL;
-       int i;
+       struct failtest_call *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;
+       tlist_for_each_rev(&history, i, list) {
+               if (i->type == FAILTEST_OPEN) {
+                       int fd = i->u.open.ret;
                        /* Only do successful, writable fds. */
                        if (fd < 0)
                                continue;
 
                        /* If it was closed, cleanup == NULL. */
-                       if (!history[i].cleanup)
+                       if (!i->cleanup)
                                continue;
 
-                       if ((history[i].u.open.flags & O_RDWR) == O_RDWR) {
+                       if ((i->u.open.flags & O_RDWR) == O_RDWR) {
                                files = save_file(files, fd);
-                       } else if ((history[i].u.open.flags & O_WRONLY)
+                       } else if ((i->u.open.flags & O_WRONLY)
                                   == O_WRONLY) {
                                /* FIXME: Handle O_WRONLY.  Open with O_RDWR? */
                                abort();
@@ -320,41 +326,48 @@ static void free_files(struct saved_file *s)
        }
 }
 
+static void free_call(struct failtest_call *call)
+{
+       /* We don't do this in cleanup: needed even for failed opens. */
+       if (call->type == FAILTEST_OPEN)
+               free((char *)call->u.open.pathname);
+       tlist_del_from(&history, call, list);
+       free(call);
+}
+
 /* Free up memory, so valgrind doesn't report leaks. */
 static void free_everything(void)
 {
-       unsigned int i;
+       struct failtest_call *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);
+       while ((i = tlist_top(&history, struct failtest_call, list)) != NULL)
+               free_call(i);
 }
 
 static NORETURN void failtest_cleanup(bool forced_cleanup, int status)
 {
-       int i;
+       struct failtest_call *i;
 
        /* For children, we don't care if they "failed" the testing. */
        if (control_fd != -1)
                status = 0;
 
-       if (forced_cleanup)
-               history_num--;
+       if (forced_cleanup) {
+               /* We didn't actually do final operation: remove it. */
+               i = tlist_tail(&history, struct failtest_call, list);
+               free_call(i);
+       }
 
        /* Cleanup everything, in reverse order. */
-       for (i = history_num - 1; i >= 0; i--) {
-               if (!history[i].cleanup)
+       tlist_for_each_rev(&history, i, list) {
+               if (!i->cleanup)
                        continue;
                if (!forced_cleanup) {
                        printf("Leak at %s:%u: --failpath=%s\n",
-                              history[i].file, history[i].line,
-                              failpath_string());
+                              i->file, i->line, failpath_string());
                        status = 1;
                }
-               history[i].cleanup(&history[i].u);
+               i->cleanup(&i->u);
        }
 
        free_everything();
@@ -390,23 +403,16 @@ static bool should_fail(struct failtest_call *call)
                            != info_to_arg[call->type])
                                errx(1, "Failpath expected '%c' got '%c'\n",
                                     info_to_arg[call->type], *failpath);
-                       call->fail = isupper((unsigned char)*(failpath++));
+                       call->fail = cisupper(*(failpath++));
                        return call->fail;
                }
        }
 
        /* Attach debugger if they asked for it. */
-       if (debugpath && history_num == strlen(debugpath)) {
-               unsigned int i;
+       if (debugpath) {
+               char *path = failpath_string();
 
-               for (i = 0; i < history_num; i++) {
-                       unsigned char c = info_to_arg[history[i].type];
-                       if (history[i].fail)
-                               c = toupper(c);
-                       if (c != debugpath[i])
-                               break;
-               }
-               if (i == history_num) {
+               if (streq(path, debugpath)) {
                        char str[80];
 
                        /* Don't timeout. */
@@ -415,11 +421,15 @@ static bool should_fail(struct failtest_call *call)
                                getpid(), getpid());
                        if (system(str) == 0)
                                sleep(5);
+               } else if (!strstarts(path, debugpath)) {
+                       fprintf(stderr, "--debugpath not followed: %s\n", path);
+                       debugpath = NULL;
                }
+               free(path);
        }
 
        if (failtest_hook) {
-               switch (failtest_hook(history, history_num)) {
+               switch (failtest_hook(&history)) {
                case FAIL_OK:
                        break;
                case FAIL_PROBE:
@@ -460,18 +470,22 @@ static bool should_fail(struct failtest_call *call)
                if (tracefd != -1) {
                        struct timeval diff;
                        const char *p;
+                       char *failpath;
+                       struct failtest_call *c;
 
+                       c = tlist_tail(&history, struct failtest_call, list);
                        diff = time_sub(time_now(), start);
-                       p = failpath_string();
+                       failpath = failpath_string();
                        trace("%u->%u (%u.%02u): %s (", getppid(), getpid(),
-                             (int)diff.tv_sec, (int)diff.tv_usec / 10000, p);
-                       free((char *)p);
-                       p = strrchr(history[history_num-1].file, '/');
+                             (int)diff.tv_sec, (int)diff.tv_usec / 10000,
+                             failpath);
+                       free(failpath);
+                       p = strrchr(c->file, '/');
                        if (p)
                                trace("%s", p+1);
                        else
-                               trace("%s", history[history_num-1].file);
-                       trace(":%u)\n", history[history_num-1].line);
+                               trace("%s", c->file);
+                       trace(":%u)\n", c->line);
                }
                close(control[0]);
                close(output[0]);
@@ -619,28 +633,28 @@ static void cleanup_realloc(struct realloc_call *call)
 }
 
 /* Walk back and find out if we got this ptr from a previous routine. */
-static void fixup_ptr_history(void *ptr, unsigned int last)
+static void fixup_ptr_history(void *ptr)
 {
-       int i;
+       struct failtest_call *i;
 
        /* Start at end of history, work back. */
-       for (i = last - 1; i >= 0; i--) {
-               switch (history[i].type) {
+       tlist_for_each_rev(&history, i, list) {
+               switch (i->type) {
                case FAILTEST_REALLOC:
-                       if (history[i].u.realloc.ret == ptr) {
-                               history[i].cleanup = NULL;
+                       if (i->u.realloc.ret == ptr) {
+                               i->cleanup = NULL;
                                return;
                        }
                        break;
                case FAILTEST_MALLOC:
-                       if (history[i].u.malloc.ret == ptr) {
-                               history[i].cleanup = NULL;
+                       if (i->u.malloc.ret == ptr) {
+                               i->cleanup = NULL;
                                return;
                        }
                        break;
                case FAILTEST_CALLOC:
-                       if (history[i].u.calloc.ret == ptr) {
-                               history[i].cleanup = NULL;
+                       if (i->u.calloc.ret == ptr) {
+                               i->cleanup = NULL;
                                return;
                        }
                        break;
@@ -662,7 +676,9 @@ void *failtest_realloc(void *ptr, size_t size, const char *file, unsigned line)
                p->u.realloc.ret = NULL;
                p->error = ENOMEM;
        } else {
-               fixup_ptr_history(ptr, history_num-1);
+               /* Don't catch this one in the history fixup... */
+               p->u.realloc.ret = NULL;
+               fixup_ptr_history(ptr);
                p->u.realloc.ret = realloc(ptr, size);
                set_cleanup(p, cleanup_realloc, struct realloc_call);
        }
@@ -672,7 +688,7 @@ void *failtest_realloc(void *ptr, size_t size, const char *file, unsigned line)
 
 void failtest_free(void *ptr)
 {
-       fixup_ptr_history(ptr, history_num);
+       fixup_ptr_history(ptr);
        free(ptr);
 }
 
@@ -910,7 +926,7 @@ add_lock(struct lock_info *locks, int fd, off_t start, off_t end, int type)
 /* We trap this so we can record it: we don't fail it. */
 int failtest_close(int fd, const char *file, unsigned line)
 {
-       int i;
+       struct failtest_call *i;
        struct close_call call;
        struct failtest_call *p;
 
@@ -927,30 +943,30 @@ int failtest_close(int fd, const char *file, unsigned line)
                return close(fd);
 
        /* Trace history to find source of fd. */
-       for (i = history_num-1; i >= 0; i--) {
-               switch (history[i].type) {
+       tlist_for_each_rev(&history, i, list) {
+               switch (i->type) {
                case FAILTEST_PIPE:
                        /* From a pipe? */
-                       if (history[i].u.pipe.fds[0] == fd) {
-                               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;
+                       if (i->u.pipe.fds[0] == fd) {
+                               assert(!i->u.pipe.closed[0]);
+                               i->u.pipe.closed[0] = true;
+                               if (i->u.pipe.closed[1])
+                                       i->cleanup = NULL;
                                goto out;
                        }
-                       if (history[i].u.pipe.fds[1] == fd) {
-                               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;
+                       if (i->u.pipe.fds[1] == fd) {
+                               assert(!i->u.pipe.closed[1]);
+                               i->u.pipe.closed[1] = true;
+                               if (i->u.pipe.closed[0])
+                                       i->cleanup = NULL;
                                goto out;
                        }
                        break;
                case FAILTEST_OPEN:
-                       if (history[i].u.open.ret == fd) {
-                               assert((void *)history[i].cleanup
+                       if (i->u.open.ret == fd) {
+                               assert((void *)i->cleanup
                                       == (void *)cleanup_open);
-                               history[i].cleanup = NULL;
+                               i->cleanup = NULL;
                                goto out;
                        }
                        break;
@@ -1074,7 +1090,7 @@ bool failtest_has_failed(void)
 void failtest_exit(int status)
 {
        if (failtest_exit_check) {
-               if (!failtest_exit_check(history, history_num))
+               if (!failtest_exit_check(&history))
                        child_fail(NULL, 0, "failtest_exit_check failed\n");
        }
 
index 0cc8f60c51ba15aa48e207c6088bfe4d39b70050..294c28b970066fda3b0e22fb3bf7ffe03140ad72 100644 (file)
@@ -9,6 +9,7 @@
 #include <stdbool.h>
 #include <fcntl.h>
 #include <ccan/compiler/compiler.h>
+#include <ccan/tlist/tlist.h>
 
 /**
  * failtest_init - initialize the failtest module
@@ -124,6 +125,8 @@ struct fcntl_call {
  *     failtest_hook, failtest_exit_check
  */
 struct failtest_call {
+       /* We're in the history list. */
+       struct list_node list;
        enum failtest_call_type type;
        /* Where we were called from. */
        const char *file;
@@ -148,6 +151,9 @@ struct failtest_call {
        } u;
 };
 
+/* This defines struct tlist_calls. */
+TLIST_TYPE(calls, struct failtest_call);
+
 enum failtest_result {
        /* Yes try failing this call. */
        FAIL_OK,
@@ -160,7 +166,6 @@ enum failtest_result {
 /**
  * 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
  * FAIL_OK (ie. yes, fail the call).
@@ -170,25 +175,24 @@ enum failtest_result {
  * call.
  *
  * Example:
- *     static enum failtest_result dont_fail_alloc(struct failtest_call *hist,
- *                                                 unsigned num)
+ *     static enum failtest_result dont_fail_alloc(struct tlist_calls *history)
  *     {
- *             if (hist[num-1].type == FAILTEST_MALLOC
- *                     || hist[num-1].type == FAILTEST_CALLOC
- *                     || hist[num-1].type == FAILTEST_REALLOC)
+ *             struct failtest_call *call;
+ *             call = tlist_tail(history, struct failtest_call, list);
+ *             if (call->type == FAILTEST_MALLOC
+ *                     || call->type == FAILTEST_CALLOC
+ *                     || call->type == FAILTEST_REALLOC)
  *                     return FAIL_DONT_FAIL;
  *             return FAIL_OK;
  *     }
  *     ...
  *             failtest_hook = dont_fail_alloc;
  */
-extern enum failtest_result
-(*failtest_hook)(struct failtest_call *history, unsigned num);
+extern enum failtest_result (*failtest_hook)(struct tlist_calls *history);
 
 /**
  * failtest_exit_check - hook for additional checks on a failed child.
  * @history: the ordered history of all failtest calls.
- * @num: the number of elements in @history (greater than 0)
  *
  * Your program might have additional checks to do on failure, such as
  * check that a file is not corrupted, or than an error message has been
@@ -197,16 +201,15 @@ extern enum failtest_result
  * If this returns false, the path to this failure will be printed and the
  * overall test will fail.
  */
-extern bool (*failtest_exit_check)(struct failtest_call *history,
-                                  unsigned num);
+extern bool (*failtest_exit_check)(struct tlist_calls *history);
 
 /**
  * failtest_has_failed - determine if a failure has occurred.
  *
- * Sometimes you want to exit immediately if you've experienced a failure.
- * This is useful when you have four separate tests in your test suite,
- * and you don't want to do the next one if you've had a failure in a
- * previous one.
+ * Sometimes you want to exit immediately if you've experienced an
+ * injected failure.  This is useful when you have four separate tests
+ * in your test suite, and you don't want to do the next one if you've
+ * had a failure in a previous one.
  */
 extern bool failtest_has_failed(void);
 
index ef28a3f5a09329db0722bffbc55a0f549f3fed20..24dc1169046945f0110be6c70710f518a83cd911 100644 (file)
@@ -102,20 +102,24 @@ int main(void)
        ok1(call->u.write.fd == write_call.fd);
        ok1(call->u.write.count == write_call.count);
 
-       ok1(history_num == 7);
+       i = 0;
+       tlist_for_each(&history, call, list)
+               i++;
 
-       for (i = 0; i < history_num; i++)
-               history[i].fail = false;
+       ok1(i == 7);
+
+       tlist_for_each(&history, call, list)
+               call->fail = false;
 
        path = failpath_string();
-       ok1(strcmp(path, "cmeoprw") == 0);
+       ok1(streq(path, "cmeoprw"));
        free(path);
 
-       for (i = 0; i < history_num; i++)
-               history[i].fail = true;
+       tlist_for_each(&history, call, list)
+               call->fail = true;
 
        path = failpath_string();
-       ok1(strcmp(path, "CMEOPRW") == 0);
+       ok1(streq(path, "CMEOPRW"));
        free(path);
 
        return exit_status();
index 6ebcd6ea504017b6de1374ed40020545c02077d5..f29f213d061ee62a9647919c5d277f9abf716d10 100644 (file)
@@ -10,8 +10,7 @@
 #define SIZE 8
 
 /* We don't want to fork and fail; we're just testing lock recording. */
-static enum failtest_result dont_fail(struct failtest_call *history,
-                                     unsigned num)
+static enum failtest_result dont_fail(struct tlist_calls *history)
 {
        return FAIL_DONT_FAIL;
 }
index d24ac4c42b11077693f5126293e095eb2963e4ea..f3ef09a6c3e84b33d0ca1807967505771835f17c 100644 (file)
@@ -26,12 +26,14 @@ bool failmatch(const struct failtest_call *call,
 }
 
 static const struct failtest_call *
-find_repeat(const struct failtest_call *start, const struct failtest_call *end,
+find_repeat(const struct tlist_calls *history,
            const struct failtest_call *call)
 {
        const struct failtest_call *i;
 
-       for (i = start; i < end; i++) {
+       tlist_for_each(history, i, list) {
+               if (i != call)
+                       continue;
                if (failmatch(i, call->file, call->line, call->type))
                        return i;
        }
@@ -49,32 +51,31 @@ static bool is_unlock(const struct failtest_call *call)
                && call->u.fcntl.arg.fl.l_type == F_UNLCK;
 }
 
-bool exit_check_log(struct failtest_call *history, unsigned num)
+bool exit_check_log(struct tlist_calls *history)
 {
-       unsigned int i;
+       const struct failtest_call *i;
 
-       for (i = 0; i < num; i++) {
-               if (!history[i].fail)
+       tlist_for_each(history, i, list) {
+               if (!i->fail)
                        continue;
                /* Failing the /dev/urandom open doesn't count: we fall back. */
-               if (failmatch(&history[i], URANDOM_OPEN))
+               if (failmatch(i, URANDOM_OPEN))
                        continue;
 
                /* Similarly with read fail. */
-               if (failmatch(&history[i], URANDOM_READ))
+               if (failmatch(i, URANDOM_READ))
                        continue;
 
                /* Initial allocation of tdb doesn't log. */
-               if (failmatch(&history[i], INITIAL_TDB_MALLOC))
+               if (failmatch(i, INITIAL_TDB_MALLOC))
                        continue;
 
                /* We don't block "failures" on non-blocking locks. */
-               if (is_nonblocking_lock(&history[i]))
+               if (is_nonblocking_lock(i))
                        continue;
 
                if (!tap_log_messages)
-                       diag("We didn't log for %u (%s:%u)",
-                            i, history[i].file, history[i].line);
+                       diag("We didn't log for %s:%u", i->file, i->line);
                return tap_log_messages != 0;
        }
        return true;
@@ -82,9 +83,11 @@ bool exit_check_log(struct failtest_call *history, unsigned num)
 
 /* Some places we soldier on despite errors: only fail them once. */
 enum failtest_result
-block_repeat_failures(struct failtest_call *history, unsigned num)
+block_repeat_failures(struct tlist_calls *history)
 {
-       const struct failtest_call *i, *last = &history[num-1];
+       const struct failtest_call *i, *last;
+
+       last = tlist_tail(history, struct failtest_call, list);
 
        if (failtest_suppress)
                return FAIL_DONT_FAIL;
@@ -92,7 +95,7 @@ block_repeat_failures(struct failtest_call *history, unsigned num)
        if (failmatch(last, INITIAL_TDB_MALLOC)
            || failmatch(last, URANDOM_OPEN)
            || failmatch(last, URANDOM_READ)) {
-               if (find_repeat(history, last, last))
+               if (find_repeat(history, last))
                        return FAIL_DONT_FAIL;
                return FAIL_PROBE;
        }
@@ -100,21 +103,15 @@ block_repeat_failures(struct failtest_call *history, unsigned num)
        /* Unlock or non-blocking lock is fail-once. */
        if (is_unlock(last)) {
                /* Find a previous unlock at this point? */
-               for (i = find_repeat(history, last, last);
-                    i;
-                    i = find_repeat(history, i, last)) {
-                       if (is_unlock(i))
-                               return FAIL_DONT_FAIL;
-               }
+               i = find_repeat(history, last);
+               if (i && is_unlock(i))
+                       return FAIL_DONT_FAIL;
                return FAIL_PROBE;
        } else if (is_nonblocking_lock(last)) {
                /* Find a previous non-blocking lock at this point? */
-               for (i = find_repeat(history, last, last);
-                    i;
-                    i = find_repeat(history, i, last)) {
-                       if (is_nonblocking_lock(i))
-                               return FAIL_DONT_FAIL;
-               }
+               i = find_repeat(history, last);
+               if (i && is_nonblocking_lock(i))
+                       return FAIL_DONT_FAIL;
                return FAIL_PROBE;
        }
 
index 7f912bb5e9146ba312f90ec904e1c9ff6641a278..a3c680885d6ec54e937908ccdb34fdc0d691abc8 100644 (file)
@@ -8,11 +8,10 @@
 #define URANDOM_OPEN           "open.c", 62, FAILTEST_OPEN
 #define URANDOM_READ           "open.c", 42, FAILTEST_READ
 
-bool exit_check_log(struct failtest_call *history, unsigned num);
+bool exit_check_log(struct tlist_calls *history);
 bool failmatch(const struct failtest_call *call,
               const char *file, int line, enum failtest_call_type type);
-enum failtest_result
-block_repeat_failures(struct failtest_call *history, unsigned num);
+enum failtest_result block_repeat_failures(struct tlist_calls *history);
 
 /* Set this to suppress failure. */
 extern bool failtest_suppress;