revisions API users: use release_revisions() needing REV_INFO_INIT

Use release_revisions() to various users of "struct rev_list" which
need to have their "struct rev_info" zero-initialized before we can
start using it.

For the bundle.c code see the early exit case added in
3bbbe467f29 (bundle verify: error out if called without an object
database, 2019-05-27).

For the relevant bisect.c code see 45b6370812c (bisect: libify
`check_good_are_ancestors_of_bad` and its dependents, 2020-02-17).

For the submodule.c code see the "goto" on "(!left || !right || !sub)"
added in 8e6df65015f (submodule: refactor show_submodule_summary with
helper function, 2016-08-31).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/bisect.c b/bisect.c
index cc6b8b6230d36e154a95a4b74de48e81b0260762..b63669cc9d768fd1de2cbc06e20e942f77ffcda7 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -1010,7 +1010,7 @@ void read_bisect_terms(const char **read_bad, const char **read_good)
  */
 enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 {
-       struct rev_info revs;
+       struct rev_info revs = REV_INFO_INIT;
        struct commit_list *tried;
        int reaches = 0, all = 0, nr, steps;
        enum bisect_error res = BISECT_OK;
@@ -1035,7 +1035,7 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 
        res = check_good_are_ancestors_of_bad(r, prefix, no_checkout);
        if (res)
-               return res;
+               goto cleanup;
 
        bisect_rev_setup(r, &revs, prefix, "%s", "^%s", 1);
 
@@ -1060,14 +1060,16 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
                       term_good,
                       term_bad);
 
-               return BISECT_FAILED;
+               res = BISECT_FAILED;
+               goto cleanup;
        }
 
        if (!all) {
                fprintf(stderr, _("No testable commit found.\n"
                        "Maybe you started with bad path arguments?\n"));
 
-               return BISECT_NO_TESTABLE_COMMIT;
+               res = BISECT_NO_TESTABLE_COMMIT;
+               goto cleanup;
        }
 
        bisect_rev = &revs.commits->item->object.oid;
@@ -1087,7 +1089,8 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
                 * for negative return values for early returns up
                 * until the cmd_bisect__helper() caller.
                 */
-               return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
+               res = BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
+               goto cleanup;
        }
 
        nr = all - reaches - 1;
@@ -1106,7 +1109,10 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
        /* Clean up objects used, as they will be reused. */
        repo_clear_commit_marks(r, ALL_REV_FLAGS);
 
-       return bisect_checkout(bisect_rev, no_checkout);
+       res = bisect_checkout(bisect_rev, no_checkout);
+cleanup:
+       release_revisions(&revs);
+       return res;
 }
 
 static inline int log2i(int n)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 24980863f68d902285a14e7b144689ac16ed3728..cda33ee4d2bfc5a4e29d8fa40782e7b69cc80151 100644 (file)
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -766,7 +766,7 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 {
        char *displaypath;
        struct strvec diff_files_args = STRVEC_INIT;
-       struct rev_info rev;
+       struct rev_info rev = REV_INFO_INIT;
        int diff_files_result;
        struct strbuf buf = STRBUF_INIT;
        const char *git_dir;
@@ -853,6 +853,7 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 cleanup:
        strvec_clear(&diff_files_args);
        free(displaypath);
+       release_revisions(&rev);
 }
 
 static void status_submodule_cb(const struct cache_entry *list_item,

diff --git a/bundle.c b/bundle.c
index d50cfb5aa7e9c28afc121f9bf27499518a3fee37..6a870a6edb72c2918876a45f2f19b6fbcd3d8696 100644 (file)
--- a/bundle.c
+++ b/bundle.c
@@ -196,14 +196,16 @@ int verify_bundle(struct repository *r,
         * to be verbose about the errors
         */
        struct string_list *p = &header->prerequisites;
-       struct rev_info revs;
+       struct rev_info revs = REV_INFO_INIT;
        const char *argv[] = {NULL, "--all", NULL};
        struct commit *commit;
        int i, ret = 0, req_nr;
        const char *message = _("Repository lacks these prerequisite commits:");
 
-       if (!r || !r->objects || !r->objects->odb)
-               return error(_("need a repository to verify a bundle"));
+       if (!r || !r->objects || !r->objects->odb) {
+               ret = error(_("need a repository to verify a bundle"));
+               goto cleanup;
+       }
 
        repo_init_revisions(r, &revs, NULL);
        for (i = 0; i < p->nr; i++) {
@@ -221,7 +223,7 @@ int verify_bundle(struct repository *r,
                error("%s %s", oid_to_hex(oid), name);
        }
        if (revs.pending.nr != p->nr)
-               return ret;
+               goto cleanup;
        req_nr = revs.pending.nr;
        setup_revisions(2, argv, &revs, NULL);
 
@@ -284,6 +286,8 @@ int verify_bundle(struct repository *r,
                        printf_ln("The bundle uses this filter: %s",
                                  list_objects_filter_spec(&header->filter));
        }
+cleanup:
+       release_revisions(&revs);
        return ret;
 }
 

diff --git a/revision.h b/revision.h
index b9070e43428ac504e0e4c1ca3400a4473705b242..2621eb6d65af3db61d4a78885bc34c7926783a33 100644 (file)
--- a/revision.h
+++ b/revision.h
@@ -329,6 +329,25 @@ struct rev_info {
        struct tmp_objdir *remerge_objdir;
 };
 
+/**
+ * Initialize the "struct rev_info" structure with a macro.
+ *
+ * This will not fully initialize a "struct rev_info", the
+ * repo_init_revisions() function needs to be called before
+ * setup_revisions() and any revision walking takes place.
+ *
+ * Use REV_INFO_INIT to make the "struct rev_info" safe for passing to
+ * release_revisions() when it's inconvenient (e.g. due to a "goto
+ * cleanup" pattern) to arrange for repo_init_revisions() to be called
+ * before release_revisions() is called.
+ *
+ * Initializing with this REV_INFO_INIT is redundant to invoking
+ * repo_init_revisions(). If repo_init_revisions() is guaranteed to be
+ * called before release_revisions() the "struct rev_info" can be left
+ * uninitialized.
+ */
+#define REV_INFO_INIT { 0 }
+
 /**
  * Initialize a rev_info structure with default values. The third parameter may
  * be NULL or can be prefix path, and then the `.prefix` variable will be set
@@ -363,7 +382,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs,
 
 /**
  * Free data allocated in a "struct rev_info" after it's been
- * initialized with repo_init_revisions().
+ * initialized with repo_init_revisions() or REV_INFO_INIT.
  */
 void release_revisions(struct rev_info *revs);
 

diff --git a/submodule.c b/submodule.c
index 86ebd3f35c5f9162c3ff4a946c88f62051a0a012..e9c320d16de02dd4b953a6dba19266bf132f2bfe 100644 (file)
--- a/submodule.c
+++ b/submodule.c
@@ -638,7 +638,7 @@ void show_submodule_diff_summary(struct diff_options *o, const char *path,
                struct object_id *one, struct object_id *two,
                unsigned dirty_submodule)
 {
-       struct rev_info rev;
+       struct rev_info rev = REV_INFO_INIT;
        struct commit *left = NULL, *right = NULL;
        struct commit_list *merge_bases = NULL;
        struct repository *sub;
@@ -665,6 +665,7 @@ void show_submodule_diff_summary(struct diff_options *o, const char *path,
 
 out:
        free_commit_list(merge_bases);
+       release_revisions(&rev);
        clear_commit_marks(left, ~0);
        clear_commit_marks(right, ~0);
        if (sub) {