Re: [PATCH v4 1/9] submodule: add a print_config_from_gitmodules() helper

On Fri, 24 Aug 2018 16:32:38 +0200
Ævar Arnfjörð Bjarmason [off-list ref] wrote:

On Fri, Aug 24 2018, Antonio Ospite wrote:

[...]

quoted

+static int config_print_callback(const char *key_, const char *value_, void *cb_data)
+{
+	char *key = cb_data;
+
+	if (!strcmp(key, key_))
+		printf("%s\n", value_);
+
+	return 0;
+}

No problem with the code itself, but I'd find this a lot easier to read
in context if it was:

    key_ -> var
    value_ -> value
    key -> wanted_key, perhaps?

I.e. the rest of the file uses the convention of the
config_from_gitmodules callbacks getting "var" and "value",
respectively.

We don't use this convention of suffixing variables with "_" if they're
arguments to the function anywhere else.

I was new to git when I firstly wrote the code, I picked up the style
by copying from builtin/config.c (collect_config() and
show_all_config()) because I was focusing more on the functionality and
didn't bother to harmonize the style with the destination file.

quoted

+int print_config_from_gitmodules(const char *key)
+{
+	int ret;
+	char *store_key;
+
+	ret = git_config_parse_key(key, &store_key, NULL);
+	if (ret < 0)
+		return CONFIG_INVALID_KEY;

Isn't this a memory leak? I.e. we should free() and return here, no?

It is true that git_config_parse_key_1() allocates some storage even
for an invalid key, and uses the space to lowercase the key as the
parsing progresses, however it also frees the memory in the *error*
path.

So unless I am missing something I don't think there is a leak here.

[...]

quoted

diff --git a/submodule-config.h b/submodule-config.h
index dc7278eea4..ed40e9a478 100644
--- a/submodule-config.h
+++ b/submodule-config.h

@@ -56,6 +56,8 @@ void submodule_free(struct repository *r);
  */
 int check_submodule_name(const char *name);

+int print_config_from_gitmodules(const char *key);
+
 /*
  * Note: these helper functions exist solely to maintain backward
  * compatibility with 'fetch' and 'update_clone' storing configuration in

Another style nit: Makes more sense to put this new function right
underneath "submodule_free" above, instead of under 1/2 of the functions
that have a big comment describing how they work, since that comment
doesn't apply to this new function.

You are probably right, IIRC the function was firstly written before
check_submodule_name() was there. And I didn't think of moving it up
when I rebased after check_submodule_name() was added.

Your same remark may apply to the new function added in patch 02.

I'll wait for other comments to see if a v5 is really needed.

Thanks for the review Ævar.

Ciao,
   Antonio

-- 
Antonio Ospite
https://ao2.it
https://twitter.com/ao2it

A: Because it messes up the order in which people normally read text.
   See http://en.wikipedia.org/wiki/Posting_style
Q: Why is top-posting such a bad thing?