| Message ID | patch-v4-10.27-145a0f74b6a-20220331T005325Z-avarab@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | revision.[ch]: add and use release_revisions() | expand |
Hi Ævar On 31/03/2022 02:11, Ævar Arnfjörð Bjarmason wrote: > Change the initialization of the "revision" member of "struct > stash_info" to be initialized vi a macro, and more importantly that > that initializing function be tasked to free it, usually via a "goto > cleanup" pattern. > > Despite the "revision" name (and the topic of the series containing > this commit) the "stash info" has nothing to do with the "struct > rev_info". I'm making this change because in the subsequent commit > when we do want to free the "struct rev_info" via a "goto cleanup" > pattern we'd otherwise free() uninitialized memory in some cases, as > we only strbuf_init() the string in get_stash_info(). > > So while it's the smallest possible change, let's convert all users of > this pattern in the file while we're at it. > > A good follow-up to this change would be to change all the "ret = -1; > goto done;" in this file to instead use a "goto cleanup", and > initialize "int ret = -1" at the start of the relevant functions. That > would allow us to drop a lot of needless brace verbosity on two-line > "if" statements, but let's leave that alone for now. You seem to have made this change here. >[...] > @@ -861,10 +863,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) > strvec_push(&revision_args, argv[i]); > } > > - ret = get_stash_info(&info, stash_args.nr, stash_args.v); > - strvec_clear(&stash_args); > - if (ret) > - return -1; > + if (get_stash_info(&info, stash_args.nr, stash_args.v)) > + goto cleanup; > > /* > * The config settings are applied only if there are not passed > @@ -878,8 +878,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) > rev.diffopt.output_format |= DIFF_FORMAT_PATCH; > > if (!show_stat && !show_patch) { > - free_stash_info(&info); > - return 0; > + ret = 0; > + goto cleanup; > } > } > > @@ -912,8 +912,11 @@ static int show_stash(int argc, const char **argv, const char *prefix) > } > log_tree_diff_flush(&rev); > > + ret = diff_result_code(&rev.diffopt, 0);; > +cleanup: > + strvec_clear(&stash_args); This seems to be fixing a leak that's not mentioned in the commit message. > free_stash_info(&info); > - return diff_result_code(&rev.diffopt, 0); > + return ret; > } >[...] > @@ -1434,7 +1438,7 @@ static int do_push_stash(const struct pathspec *ps, const char *stash_msg, int q > int keep_index, int patch_mode, int include_untracked, int only_staged) > { > int ret = 0; > - struct stash_info info; > + struct stash_info info = STASH_INFO_INIT; There doesn't seem to be a call to free_stash_info() in this function. Best Wishes Phillip
Hi Ævar On 31/03/2022 02:11, Ævar Arnfjörð Bjarmason wrote: > Change the initialization of the "revision" member of "struct > stash_info" to be initialized vi a macro, and more importantly that > that initializing function be tasked to free it, usually via a "goto > cleanup" pattern. > > Despite the "revision" name (and the topic of the series containing > this commit) the "stash info" has nothing to do with the "struct > rev_info". I'm making this change because in the subsequent commit > when we do want to free the "struct rev_info" via a "goto cleanup" > pattern we'd otherwise free() uninitialized memory in some cases, as > we only strbuf_init() the string in get_stash_info(). > > So while it's the smallest possible change, let's convert all users of > this pattern in the file while we're at it. > > A good follow-up to this change would be to change all the "ret = -1; > goto done;" in this file to instead use a "goto cleanup", and > initialize "int ret = -1" at the start of the relevant functions. That > would allow us to drop a lot of needless brace verbosity on two-line > "if" statements, but let's leave that alone for now. >[...] > @@ -912,8 +912,11 @@ static int show_stash(int argc, const char **argv, const char *prefix) > } > log_tree_diff_flush(&rev); > > + ret = diff_result_code(&rev.diffopt, 0);; Extra ';' Best Wishes Phillip
On Fri, Apr 01 2022, Phillip Wood wrote: > Hi Ævar > > On 31/03/2022 02:11, Ævar Arnfjörð Bjarmason wrote: >> Change the initialization of the "revision" member of "struct >> stash_info" to be initialized vi a macro, and more importantly that >> that initializing function be tasked to free it, usually via a "goto >> cleanup" pattern. >> Despite the "revision" name (and the topic of the series containing >> this commit) the "stash info" has nothing to do with the "struct >> rev_info". I'm making this change because in the subsequent commit >> when we do want to free the "struct rev_info" via a "goto cleanup" >> pattern we'd otherwise free() uninitialized memory in some cases, as >> we only strbuf_init() the string in get_stash_info(). >> So while it's the smallest possible change, let's convert all users >> of >> this pattern in the file while we're at it. >> A good follow-up to this change would be to change all the "ret = >> -1; >> goto done;" in this file to instead use a "goto cleanup", and >> initialize "int ret = -1" at the start of the relevant functions. That >> would allow us to drop a lot of needless brace verbosity on two-line >> "if" statements, but let's leave that alone for now. > > You seem to have made this change here. > >>[...] >> @@ -861,10 +863,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) >> strvec_push(&revision_args, argv[i]); >> } >> - ret = get_stash_info(&info, stash_args.nr, stash_args.v); >> - strvec_clear(&stash_args); >> - if (ret) >> - return -1; >> + if (get_stash_info(&info, stash_args.nr, stash_args.v)) >> + goto cleanup; >> /* >> * The config settings are applied only if there are not passed >> @@ -878,8 +878,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) >> rev.diffopt.output_format |= DIFF_FORMAT_PATCH; >> if (!show_stat && !show_patch) { >> - free_stash_info(&info); >> - return 0; >> + ret = 0; >> + goto cleanup; >> } >> } >> @@ -912,8 +912,11 @@ static int show_stash(int argc, const char >> **argv, const char *prefix) >> } >> log_tree_diff_flush(&rev); >> + ret = diff_result_code(&rev.diffopt, 0);; >> +cleanup: >> + strvec_clear(&stash_args); > > This seems to be fixing a leak that's not mentioned in the commit message. This is just moving the exsting strvec_clear() shown above to the "cleanup" branch, as we change return to "goto cleanup". >> free_stash_info(&info); >> - return diff_result_code(&rev.diffopt, 0); >> + return ret; >> } >>[...] >> @@ -1434,7 +1438,7 @@ static int do_push_stash(const struct pathspec *ps, const char *stash_msg, int q >> int keep_index, int patch_mode, int include_untracked, int only_staged) >> { >> int ret = 0; >> - struct stash_info info; >> + struct stash_info info = STASH_INFO_INIT; > > There doesn't seem to be a call to free_stash_info() in this function. Hrm, I think you're right about that (but it was an existing leak). Will fix.
diff --git a/builtin/stash.c b/builtin/stash.c index ad74624c2f7..891572d807c 100644 --- a/builtin/stash.c +++ b/builtin/stash.c @@ -116,6 +116,10 @@ struct stash_info { int has_u; }; +#define STASH_INFO_INIT { \ + .revision = STRBUF_INIT, \ +} + static void free_stash_info(struct stash_info *info) { strbuf_release(&info->revision); @@ -157,10 +161,8 @@ static int get_stash_info(struct stash_info *info, int argc, const char **argv) if (argc == 1) commit = argv[0]; - strbuf_init(&info->revision, 0); if (!commit) { if (!ref_exists(ref_stash)) { - free_stash_info(info); fprintf_ln(stderr, _("No stash entries found.")); return -1; } @@ -174,11 +176,8 @@ static int get_stash_info(struct stash_info *info, int argc, const char **argv) revision = info->revision.buf; - if (get_oid(revision, &info->w_commit)) { - error(_("%s is not a valid reference"), revision); - free_stash_info(info); - return -1; - } + if (get_oid(revision, &info->w_commit)) + return error(_("%s is not a valid reference"), revision); assert_stash_like(info, revision); @@ -197,7 +196,7 @@ static int get_stash_info(struct stash_info *info, int argc, const char **argv) info->is_stash_ref = !strcmp(expanded_ref, ref_stash); break; default: /* Invalid or ambiguous */ - free_stash_info(info); + break; } free(expanded_ref); @@ -598,10 +597,10 @@ static int do_apply_stash(const char *prefix, struct stash_info *info, static int apply_stash(int argc, const char **argv, const char *prefix) { - int ret; + int ret = -1; int quiet = 0; int index = 0; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct option options[] = { OPT__QUIET(&quiet, N_("be quiet, only report errors")), OPT_BOOL(0, "index", &index, @@ -613,9 +612,10 @@ static int apply_stash(int argc, const char **argv, const char *prefix) git_stash_apply_usage, 0); if (get_stash_info(&info, argc, argv)) - return -1; + goto cleanup; ret = do_apply_stash(prefix, &info, index, quiet); +cleanup: free_stash_info(&info); return ret; } @@ -662,9 +662,9 @@ static void assert_stash_ref(struct stash_info *info) static int drop_stash(int argc, const char **argv, const char *prefix) { - int ret; + int ret = -1; int quiet = 0; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct option options[] = { OPT__QUIET(&quiet, N_("be quiet, only report errors")), OPT_END() @@ -674,21 +674,22 @@ static int drop_stash(int argc, const char **argv, const char *prefix) git_stash_drop_usage, 0); if (get_stash_info(&info, argc, argv)) - return -1; + goto cleanup; assert_stash_ref(&info); ret = do_drop_stash(&info, quiet); +cleanup: free_stash_info(&info); return ret; } static int pop_stash(int argc, const char **argv, const char *prefix) { - int ret; + int ret = -1; int index = 0; int quiet = 0; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct option options[] = { OPT__QUIET(&quiet, N_("be quiet, only report errors")), OPT_BOOL(0, "index", &index, @@ -700,7 +701,7 @@ static int pop_stash(int argc, const char **argv, const char *prefix) git_stash_pop_usage, 0); if (get_stash_info(&info, argc, argv)) - return -1; + goto cleanup; assert_stash_ref(&info); if ((ret = do_apply_stash(prefix, &info, index, quiet))) @@ -709,15 +710,16 @@ static int pop_stash(int argc, const char **argv, const char *prefix) else ret = do_drop_stash(&info, quiet); +cleanup: free_stash_info(&info); return ret; } static int branch_stash(int argc, const char **argv, const char *prefix) { - int ret; + int ret = -1; const char *branch = NULL; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct child_process cp = CHILD_PROCESS_INIT; struct option options[] = { OPT_END() @@ -734,7 +736,7 @@ static int branch_stash(int argc, const char **argv, const char *prefix) branch = argv[0]; if (get_stash_info(&info, argc - 1, argv + 1)) - return -1; + goto cleanup; cp.git_cmd = 1; strvec_pushl(&cp.args, "checkout", "-b", NULL); @@ -746,8 +748,8 @@ static int branch_stash(int argc, const char **argv, const char *prefix) if (!ret && info.is_stash_ref) ret = do_drop_stash(&info, 0); +cleanup: free_stash_info(&info); - return ret; } @@ -825,8 +827,8 @@ static void diff_include_untracked(const struct stash_info *info, struct diff_op static int show_stash(int argc, const char **argv, const char *prefix) { int i; - int ret = 0; - struct stash_info info; + int ret = -1; + struct stash_info info = STASH_INFO_INIT; struct rev_info rev; struct strvec stash_args = STRVEC_INIT; struct strvec revision_args = STRVEC_INIT; @@ -861,10 +863,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) strvec_push(&revision_args, argv[i]); } - ret = get_stash_info(&info, stash_args.nr, stash_args.v); - strvec_clear(&stash_args); - if (ret) - return -1; + if (get_stash_info(&info, stash_args.nr, stash_args.v)) + goto cleanup; /* * The config settings are applied only if there are not passed @@ -878,8 +878,8 @@ static int show_stash(int argc, const char **argv, const char *prefix) rev.diffopt.output_format |= DIFF_FORMAT_PATCH; if (!show_stat && !show_patch) { - free_stash_info(&info); - return 0; + ret = 0; + goto cleanup; } } @@ -912,8 +912,11 @@ static int show_stash(int argc, const char **argv, const char *prefix) } log_tree_diff_flush(&rev); + ret = diff_result_code(&rev.diffopt, 0);; +cleanup: + strvec_clear(&stash_args); free_stash_info(&info); - return diff_result_code(&rev.diffopt, 0); + return ret; } static int do_store_stash(const struct object_id *w_commit, const char *stash_msg, @@ -1409,9 +1412,9 @@ static int do_create_stash(const struct pathspec *ps, struct strbuf *stash_msg_b static int create_stash(int argc, const char **argv, const char *prefix) { - int ret = 0; + int ret; struct strbuf stash_msg_buf = STRBUF_INIT; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct pathspec ps; /* Starting with argv[1], since argv[0] is "create" */ @@ -1426,6 +1429,7 @@ static int create_stash(int argc, const char **argv, const char *prefix) if (!ret) printf_ln("%s", oid_to_hex(&info.w_commit)); + free_stash_info(&info); strbuf_release(&stash_msg_buf); return ret; } @@ -1434,7 +1438,7 @@ static int do_push_stash(const struct pathspec *ps, const char *stash_msg, int q int keep_index, int patch_mode, int include_untracked, int only_staged) { int ret = 0; - struct stash_info info; + struct stash_info info = STASH_INFO_INIT; struct strbuf patch = STRBUF_INIT; struct strbuf stash_msg_buf = STRBUF_INIT; struct strbuf untracked_files = STRBUF_INIT;
Change the initialization of the "revision" member of "struct stash_info" to be initialized vi a macro, and more importantly that that initializing function be tasked to free it, usually via a "goto cleanup" pattern. Despite the "revision" name (and the topic of the series containing this commit) the "stash info" has nothing to do with the "struct rev_info". I'm making this change because in the subsequent commit when we do want to free the "struct rev_info" via a "goto cleanup" pattern we'd otherwise free() uninitialized memory in some cases, as we only strbuf_init() the string in get_stash_info(). So while it's the smallest possible change, let's convert all users of this pattern in the file while we're at it. A good follow-up to this change would be to change all the "ret = -1; goto done;" in this file to instead use a "goto cleanup", and initialize "int ret = -1" at the start of the relevant functions. That would allow us to drop a lot of needless brace verbosity on two-line "if" statements, but let's leave that alone for now. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- builtin/stash.c | 70 ++++++++++++++++++++++++++----------------------- 1 file changed, 37 insertions(+), 33 deletions(-)