threads / patch / 41553

patchenvironment.c: introduce SETUP_GIT_ENV helper macro

Subject: [PATCH] environment.c: introduce SETUP_GIT_ENV helper macro

## tl;dr

4 messages between Feb 27, 2016 and Feb 27, 2016. Diffs are folded; open one to read it.

replies: 3people: 2as markdown or json

Alexander Kuleshov· Feb 27, 2016, 17:13 UTC · lore

The environment.c contans a couple of functions which are consist from the following pattern:

        if (!env)
                setup_git_env();
        return env;

Let's move this to the SETUP_GIT_ENV helper macro to prevent code duplication in these functions.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
---
 environment.c | 25 ++++++++++---------------
 1 file changed, 10 insertions(+), 15 deletions(-)

Show changes to environment.c +10 −15

diff --git a/environment.c b/environment.c
index 6dec9d0..04cb6cd 100644
--- a/environment.c
+++ b/environment.c
@@ -126,6 +126,11 @@ const char * const local_repo_env[] = {
 	NULL
 };
 
+#define SETUP_GIT_ENV(env)              \
+	if (!env)                       \
+		setup_git_env();        \
+	return env;
+
 static char *expand_namespace(const char *raw_namespace)
 {
 	struct strbuf buf = STRBUF_INIT;
@@ -199,9 +204,7 @@ int is_bare_repository(void)
 
 const char *get_git_dir(void)
 {
-	if (!git_dir)
-		setup_git_env();
-	return git_dir;
+	SETUP_GIT_ENV(git_dir);
 }
 
 const char *get_git_common_dir(void)
@@ -211,9 +214,7 @@ const char *get_git_common_dir(void)
 
 const char *get_git_namespace(void)
 {
-	if (!namespace)
-		setup_git_env();
-	return namespace;
+	SETUP_GIT_ENV(namespace);
 }
 
 const char *strip_namespace(const char *namespaced_ref)
@@ -251,9 +252,7 @@ const char *get_git_work_tree(void)
 
 char *get_object_directory(void)
 {
-	if (!git_object_dir)
-		setup_git_env();
-	return git_object_dir;
+	SETUP_GIT_ENV(git_object_dir);
 }
 
 int odb_mkstemp(char *template, size_t limit, const char *pattern)
@@ -295,16 +294,12 @@ int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1)
 
 char *get_index_file(void)
 {
-	if (!git_index_file)
-		setup_git_env();
-	return git_index_file;
+	SETUP_GIT_ENV(git_index_file);
 }
 
 char *get_graft_file(void)
 {
-	if (!git_graft_file)
-		setup_git_env();
-	return git_graft_file;
+	SETUP_GIT_ENV(git_graft_file);
 }
 
 int set_git_dir(const char *path)

-- 
2.5.0

Junio C Hamano· Feb 27, 2016, 17:51 UTC · re: Alexander Kuleshov · lore

Re: [PATCH] environment.c: introduce SETUP_GIT_ENV helper macro

Alexander Kuleshov <kuleshovmail@gmail.com> writes:

Show 9 quoted lines

> The environment.c contans a couple of functions which are
> consist from the following pattern:
>
>         if (!env)
>                 setup_git_env();
>         return env;
>
> Let's move this to the SETUP_GIT_ENV helper macro to prevent
> code duplication in these functions.

Please don't. A macro that hides "return" makes things harder to follow, not easier.

Show 74 quoted lines

>
> Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
> ---
>  environment.c | 25 ++++++++++---------------
>  1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/environment.c b/environment.c
> index 6dec9d0..04cb6cd 100644
> --- a/environment.c
> +++ b/environment.c
> @@ -126,6 +126,11 @@ const char * const local_repo_env[] = {
>  	NULL
>  };
>  
> +#define SETUP_GIT_ENV(env)              \
> +	if (!env)                       \
> +		setup_git_env();        \
> +	return env;
> +
>  static char *expand_namespace(const char *raw_namespace)
>  {
>  	struct strbuf buf = STRBUF_INIT;
> @@ -199,9 +204,7 @@ int is_bare_repository(void)
>  
>  const char *get_git_dir(void)
>  {
> -	if (!git_dir)
> -		setup_git_env();
> -	return git_dir;
> +	SETUP_GIT_ENV(git_dir);
>  }
>  
>  const char *get_git_common_dir(void)
> @@ -211,9 +214,7 @@ const char *get_git_common_dir(void)
>  
>  const char *get_git_namespace(void)
>  {
> -	if (!namespace)
> -		setup_git_env();
> -	return namespace;
> +	SETUP_GIT_ENV(namespace);
>  }
>  
>  const char *strip_namespace(const char *namespaced_ref)
> @@ -251,9 +252,7 @@ const char *get_git_work_tree(void)
>  
>  char *get_object_directory(void)
>  {
> -	if (!git_object_dir)
> -		setup_git_env();
> -	return git_object_dir;
> +	SETUP_GIT_ENV(git_object_dir);
>  }
>  
>  int odb_mkstemp(char *template, size_t limit, const char *pattern)
> @@ -295,16 +294,12 @@ int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1)
>  
>  char *get_index_file(void)
>  {
> -	if (!git_index_file)
> -		setup_git_env();
> -	return git_index_file;
> +	SETUP_GIT_ENV(git_index_file);
>  }
>  
>  char *get_graft_file(void)
>  {
> -	if (!git_graft_file)
> -		setup_git_env();
> -	return git_graft_file;
> +	SETUP_GIT_ENV(git_graft_file);
>  }
>  
>  int set_git_dir(const char *path)

Junio C Hamano· Feb 27, 2016, 18:50 UTC · re: Junio C Hamano · lore

Re: [PATCH] environment.c: introduce SETUP_GIT_ENV helper macro

Junio C Hamano <gitster@pobox.com> writes:

Show 25 quoted lines

> Alexander Kuleshov <kuleshovmail@gmail.com> writes:
>
>> Let's move this to the SETUP_GIT_ENV helper macro to prevent
>> code duplication in these functions.
>
> Please don't.  A macro that hides "return" makes things harder to
> follow, not easier.
>>
>> +#define SETUP_GIT_ENV(env)              \
>> +	if (!env)                       \
>> +		setup_git_env();        \
>> +	return env;
>> +
>>  static char *expand_namespace(const char *raw_namespace)
>>  {
>>  	struct strbuf buf = STRBUF_INIT;
>> @@ -199,9 +204,7 @@ int is_bare_repository(void)
>>  
>>  const char *get_git_dir(void)
>>  {
>> -	if (!git_dir)
>> -		setup_git_env();
>> -	return git_dir;
>> +	SETUP_GIT_ENV(git_dir);
>>  }

Having said that, I do think a higher-level macro that encapulates the whole thing may not be such a bad idea, i.e. making the above into

    DECLARE_GIT_GETTER(const char *, get_git_dir, git_dir)

and this and others

Show 7 quoted lines

>>  char *get_object_directory(void)
>>  {
>> -	if (!git_object_dir)
>> -		setup_git_env();
>> -	return git_object_dir;
>> +	SETUP_GIT_ENV(git_object_dir);
>>  }

into

    DECLARE_GIT_GETTER(char *, get_object_directory, git_object_dir)
    DECLARE_GIT_GETTER(char *, get_index_file, git_index_file)
    DECLARE_GIT_GETTER(char *, get_graft_file, git_graft_file)

Alexander Kuleshov· Feb 27, 2016, 19:10 UTC · re: Junio C Hamano · lore

Re: [PATCH] environment.c: introduce SETUP_GIT_ENV helper macro

Hello Junio,

On Sun, Feb 28, 2016 at 12:50 AM, Junio C Hamano <gitster@pobox.com> wrote:

Show 5 quoted lines

> Junio C Hamano <gitster@pobox.com> writes:
>
>
>> Please don't.  A macro that hides "return" makes things harder to
>> follow, not easier.

I will consider it next time.

Show 5 quoted lines

> Having said that, I do think a higher-level macro that encapulates
> the whole thing may not be such a bad idea, i.e. making the above
> into
>
>     DECLARE_GIT_GETTER(const char *, get_git_dir, git_dir)

Yes, it is better. Will resend the patch.

Thank you.