[PATCH 0/2] git-compat-util: move convert_slashes from compat/mingw.h and rename it

[PATCH 0/2] git-compat-util: move convert_slashes from compat/mingw.h and rename it

[Mohit Marathe via GitGitGadget]

Hi all,

This series aims to complete a #leftoverbits: https://lore.kernel.org/
git/xmqqzfw43xad.fsf@gitster.g/ by moving convert_slashes() to
git-compat-util.h and renaming it to change_path_separators().

I appreciate your review and feedback on this patch series.

Best regards, Mohit Marathe

Mohit Marathe (2):
  git-compat-util: migrate `convert_slashes()` from compat/mingw.h
  test-lib: replace repeated code logic with an existing helper

 abspath.c               | 4 ++--
 compat/mingw.c          | 4 ++--
 compat/mingw.h          | 6 ------
 git-compat-util.h       | 7 +++++++
 path.c                  | 2 +-
 t/unit-tests/test-lib.c | 9 +++------
 6 files changed, 15 insertions(+), 17 deletions(-)


base-commit: 2953d95d402b6bff1a59c4712f4d46f1b9ea137f
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1699%2Fmohit-marathe%2Fconvert-slashes-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1699/mohit-marathe/convert-slashes-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1699
-- 
gitgitgadget

[PATCH 1/2] git-compat-util: migrate `convert_slashes()` from compat/mingw.h

[Mohit Marathe via GitGitGadget]

From: Mohit Marathe <mohitmarathe@proton.me>

This patch migrates the `convert_slashes` function to `git-compat-
util.h` and renames it to `change_path_separators`.

Signed-off-by: Mohit Marathe <mohitmarathe@proton.me>
---
 abspath.c         | 4 ++--
 compat/mingw.c    | 4 ++--
 compat/mingw.h    | 6 ------
 git-compat-util.h | 7 +++++++
 path.c            | 2 +-
 5 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/abspath.c b/abspath.c
index 1202cde23db..ea35e2c05ce 100644
--- a/abspath.c
+++ b/abspath.c
@@ -58,7 +58,7 @@ static void get_root_part(struct strbuf *resolved, struct strbuf *remaining)
 	strbuf_reset(resolved);
 	strbuf_add(resolved, remaining->buf, offset);
 #ifdef GIT_WINDOWS_NATIVE
-	convert_slashes(resolved->buf);
+	change_path_separators(resolved->buf);
 #endif
 	strbuf_remove(remaining, 0, offset);
 }
@@ -278,7 +278,7 @@ char *prefix_filename(const char *pfx, const char *arg)
 
 	strbuf_addstr(&path, arg);
 #ifdef GIT_WINDOWS_NATIVE
-	convert_slashes(path.buf + pfx_len);
+	change_path_separators(path.buf + pfx_len);
 #endif
 	return strbuf_detach(&path, NULL);
 }
diff --git a/compat/mingw.c b/compat/mingw.c
index 320fb99a90e..f7c1a009563 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1170,7 +1170,7 @@ char *mingw_getcwd(char *pointer, int len)
 	}
 	if (xwcstoutf(pointer, wpointer, len) < 0)
 		return NULL;
-	convert_slashes(pointer);
+	change_path_separators(pointer);
 	return pointer;
 }
 
@@ -2636,7 +2636,7 @@ static void setup_windows_environment(void)
 		 * executable (by not mistaking the dir separators
 		 * for escape characters).
 		 */
-		convert_slashes(tmp);
+		change_path_separators(tmp);
 	}
 
 	/* simulate TERM to enable auto-color (see color.c) */
diff --git a/compat/mingw.h b/compat/mingw.h
index 6aec50e4124..f5ca4adc194 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -448,12 +448,6 @@ HANDLE winansi_get_osfhandle(int fd);
  * git specific compatibility
  */
 
-static inline void convert_slashes(char *path)
-{
-	for (; *path; path++)
-		if (*path == '\\')
-			*path = '/';
-}
 #define PATH_SEP ';'
 char *mingw_query_user_email(void);
 #define query_user_email mingw_query_user_email
diff --git a/git-compat-util.h b/git-compat-util.h
index 7c2a6538e5a..3db90c09295 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1309,6 +1309,13 @@ static inline int strtol_i(char const *s, int base, int *result)
 	return 0;
 }
 
+static inline void change_path_separators(char *path)
+{
+	for (; *path; path++)
+		if (*path == '\\')
+			*path = '/';
+}
+
 void git_stable_qsort(void *base, size_t nmemb, size_t size,
 		      int(*compar)(const void *, const void *));
 #ifdef INTERNAL_QSORT
diff --git a/path.c b/path.c
index 8bb223c92c9..cd7c88ffa0d 100644
--- a/path.c
+++ b/path.c
@@ -758,7 +758,7 @@ char *interpolate_path(const char *path, int real_home)
 			else
 				strbuf_addstr(&user_path, home);
 #ifdef GIT_WINDOWS_NATIVE
-			convert_slashes(user_path.buf);
+			change_path_separators(user_path.buf);
 #endif
 		} else {
 			struct passwd *pw = getpw_str(username, username_len);
-- 
gitgitgadget

Re: [PATCH 1/2] git-compat-util: migrate `convert_slashes()` from compat/mingw.h

[Junio C Hamano]

"Mohit Marathe via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Mohit Marathe <mohitmarathe@proton.me>
>
> This patch migrates the `convert_slashes` function to `git-compat-
> util.h` and renames it to `change_path_separators`.

That is something a reader can tell from looking at what the patch
does.  What they cannot read from the diff is why the author of the
patch thought it was a good idea and that is what we want to see
here.

> diff --git a/abspath.c b/abspath.c
> index 1202cde23db..ea35e2c05ce 100644
> --- a/abspath.c
> +++ b/abspath.c
> @@ -58,7 +58,7 @@ static void get_root_part(struct strbuf *resolved, struct strbuf *remaining)
>  	strbuf_reset(resolved);
>  	strbuf_add(resolved, remaining->buf, offset);
>  #ifdef GIT_WINDOWS_NATIVE
> -	convert_slashes(resolved->buf);
> +	change_path_separators(resolved->buf);
>  #endif

In the context of "#ifdef GIT_WINDOWS_NATIVE..#endif" conditional
compilation, the name convert_slashes() may have made some sense,
i.e. "on this system, we get a path with the kind of slash that is
not suitable to be used in Git, so we correct it to the other kind
of slash".  But neither it, or change_path_separators(), as a name
of public function makes much sense.  The direction of the change
is totally unclear.

"normalize" may be a verb that has some connotation which direction
the conversion is going, but still, without knowing why this change
is being made (not the name change, but the part that makes it public),
I cannot offer much better candidates for its name.

> diff --git a/git-compat-util.h b/git-compat-util.h
> index 7c2a6538e5a..3db90c09295 100644
> --- a/git-compat-util.h
> +++ b/git-compat-util.h
> @@ -1309,6 +1309,13 @@ static inline int strtol_i(char const *s, int base, int *result)
>  	return 0;
>  }
>  
> +static inline void change_path_separators(char *path)
> +{
> +	for (; *path; path++)
> +		if (*path == '\\')
> +			*path = '/';
> +}
> +
>  void git_stable_qsort(void *base, size_t nmemb, size_t size,
>  		      int(*compar)(const void *, const void *));
>  #ifdef INTERNAL_QSORT
> diff --git a/path.c b/path.c
> index 8bb223c92c9..cd7c88ffa0d 100644
> --- a/path.c
> +++ b/path.c
> @@ -758,7 +758,7 @@ char *interpolate_path(const char *path, int real_home)
>  			else
>  				strbuf_addstr(&user_path, home);
>  #ifdef GIT_WINDOWS_NATIVE
> -			convert_slashes(user_path.buf);
> +			change_path_separators(user_path.buf);
>  #endif
>  		} else {
>  			struct passwd *pw = getpw_str(username, username_len);

If the idea were that "here we know that the path came from reading
filesystem and on platforms that use backslashes as path separators,
we need to normalize them into slashes before the path is usable in
Git", then I might understand if a change were more like:

 * Introduce normalize_path_separators_in_place(char *) that is a
   NOOP by default, but does the backslash->slash conversion ONLY on
   platforms that require it (i.e. Windows).

 * Lose "#ifdef GIT_WINDOWS_NATIVE" and corresponding "#endif", and
   call that normalize thing unconditionally, which gets optimized
   away on most systems other then where it is required.

That way, the affected .c files would become somewhat easier to
follow without ugly conditional compilation.

But with the proposed patch lacking any explanation why the author
thought it was a good idea, the above is just my wild guess.

[PATCH 2/2] test-lib: replace repeated code logic with an existing helper

[Mohit Marathe via GitGitGadget]

From: Mohit Marathe <mohitmarathe@proton.me>

This patch replaces the code, that changes the path separators,
with the already existing function `change_path_separators()`

Signed-off-by: Mohit Marathe <mohitmarathe@proton.me>
---
 t/unit-tests/test-lib.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/t/unit-tests/test-lib.c b/t/unit-tests/test-lib.c
index 66d6980ffbe..b0e26263046 100644
--- a/t/unit-tests/test-lib.c
+++ b/t/unit-tests/test-lib.c
@@ -52,9 +52,7 @@ static const char *make_relative(const char *location)
 		prefix_len = len - needle_len;
 		if (prefix[prefix_len + 1] == '/') {
 			/* Oh, we're not Windows */
-			for (size_t i = 0; i < needle_len; i++)
-				if (needle[i] == '\\')
-					needle[i] = '/';
+			change_path_separators(&needle[0]);
 			need_bs_to_fs = 0;
 		} else {
 			need_bs_to_fs = 1;
@@ -88,9 +86,8 @@ static const char *make_relative(const char *location)
 
 	/* convert backslashes to forward slashes */
 	strlcpy(buf, location + prefix_len, sizeof(buf));
-	for (p = buf; *p; p++)
-		if (*p == '\\')
-			*p = '/';
+	p = buf;
+	change_path_separators(p);
 	return buf;
 }
 
-- 
gitgitgadget

Re: [PATCH 2/2] test-lib: replace repeated code logic with an existing helper

[Junio C Hamano]

"Mohit Marathe via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Mohit Marathe <mohitmarathe@proton.me>
>
> This patch replaces the code, that changes the path separators,
> with the already existing function `change_path_separators()`

Aside from that the name change_path_separators() needs to be
updated, using it here means that the helper cannot become a NO-OP
on platforms where we do not have to change backslashes we read from
the system to forward slashes.  So if we really wanted to use it
here, and update the other existing callers in the main code to help
them lose the ugly "#if WINDOWS" conditional compilation, we would
need two helper functions, perhaps one that is used here that is
identical to the current convert_slashes(), and the other one used
to clean-up the callsites in [1/2] to also remove the conditional
compilation.

Even if we were to make it public, I am not sure if compat-util is
the right place, though.  It is not a kitchen sink.

In any case, perhaps we want to do something like this in a header,
...

	static inline void bs_to_forward_slash_in_place(char *path)
	{
		...
	}
	#ifdef GIT_WINDOWS_NATIVE
	#define normalize_slashes_in_place(path) bs_to_forward_slash_in_place(path)
	#else
	#define normalize_slashes_in_place(path) do { ; /* nothing */ } while (0)
	#endif

... and then use the "normalize" one to lose "#ifdef" in the callers
[1/2] touches, while "bs_to_forward_slash" one here.

I am not convinced if it is worth doing only for this single test,
though.

> @@ -88,9 +86,8 @@ static const char *make_relative(const char *location)
>  
>  	/* convert backslashes to forward slashes */
>  	strlcpy(buf, location + prefix_len, sizeof(buf));
> -	for (p = buf; *p; p++)
> -		if (*p == '\\')
> -			*p = '/';
> +	p = buf;
> +	change_path_separators(p);
>  	return buf;
>  }

Re: [PATCH 2/2] test-lib: replace repeated code logic with an existing helper

[Josh Steadmon]

On 2024.03.18 12:47, Mohit Marathe via GitGitGadget wrote:
> From: Mohit Marathe <mohitmarathe@proton.me>
> 
> This patch replaces the code, that changes the path separators,
> with the already existing function `change_path_separators()`
> 
> Signed-off-by: Mohit Marathe <mohitmarathe@proton.me>
> ---
>  t/unit-tests/test-lib.c | 9 +++------
>  1 file changed, 3 insertions(+), 6 deletions(-)
> 
> diff --git a/t/unit-tests/test-lib.c b/t/unit-tests/test-lib.c
> index 66d6980ffbe..b0e26263046 100644
> --- a/t/unit-tests/test-lib.c
> +++ b/t/unit-tests/test-lib.c
> @@ -52,9 +52,7 @@ static const char *make_relative(const char *location)
>  		prefix_len = len - needle_len;
>  		if (prefix[prefix_len + 1] == '/') {
>  			/* Oh, we're not Windows */
> -			for (size_t i = 0; i < needle_len; i++)
> -				if (needle[i] == '\\')
> -					needle[i] = '/';
> +			change_path_separators(&needle[0]);

Why not just:
change_path_separators(needle);
?

>  			need_bs_to_fs = 0;
>  		} else {
>  			need_bs_to_fs = 1;
> @@ -88,9 +86,8 @@ static const char *make_relative(const char *location)
>  
>  	/* convert backslashes to forward slashes */
>  	strlcpy(buf, location + prefix_len, sizeof(buf));
> -	for (p = buf; *p; p++)
> -		if (*p == '\\')
> -			*p = '/';
> +	p = buf;
> +	change_path_separators(p);

And here, why not:
change_path_separators(buf)
?

>  	return buf;
>  }
>  
> -- 
> gitgitgadget
>