Subject: Re: [PATCH 2/4] dir.[ch]: expose 'get_dtype'

From: Junio C Hamano <[email-masked]>
Date: Fri, 06 Oct 2023 15:00:17 -0700

"Victoria Dye via GitGitGadget" <[email-masked]> writes:

> From: Victoria Dye <[email-masked]>
>
> Move 'get_dtype()' from 'diagnose.c' to 'dir.c' and add its declaration to
> 'dir.h' so that it is accessible to callers in other files. The function and
> its documentation are moved verbatim except for a small addition to the
> description clarifying what the 'path' arg represents.
>
> Signed-off-by: Victoria Dye <[email-masked]>
> ---
>  diagnose.c | 36 ------------------------------------
>  dir.c      | 28 ++++++++++++++++++++++++++++
>  dir.h      | 11 +++++++++++
>  3 files changed, 39 insertions(+), 36 deletions(-)

OK.  diagnose.c should still have access to the function as it
includes <dir.h>, and to anybody that includes <dir.h> and sees the
declaration of get_dtype(), DT_FOO should be visible because <dir.h>
includes <statinfo.h> that has fallback definition of DT_FOO.

Looking simple and straight-forward.

> diff --git a/diagnose.c b/diagnose.c
> index 8430064000b..fc4d344bd63 100644
> --- a/diagnose.c
> +++ b/diagnose.c
> @@ -71,42 +71,6 @@ static int dir_file_stats(struct object_directory *object_dir, void *data)
>  	return 0;
>  }
>  
> -/*
> - * Get the d_type of a dirent. If the d_type is unknown, derive it from
> - * stat.st_mode.
> - *
> - * Note that 'path' is assumed to have a trailing slash. It is also modified
> - * in-place during the execution of the function, but is then reverted to its
> - * original value before returning.
> - */
> -static unsigned char get_dtype(struct dirent *e, struct strbuf *path)
> -{
> -	struct stat st;
> -	unsigned char dtype = DTYPE(e);
> -	size_t base_path_len;
> -
> -	if (dtype != DT_UNKNOWN)
> -		return dtype;
> -
> -	/* d_type unknown in dirent, try to fall back on lstat results */
> -	base_path_len = path->len;
> -	strbuf_addstr(path, e->d_name);
> -	if (lstat(path->buf, &st))
> -		goto cleanup;
> -
> -	/* determine d_type from st_mode */
> -	if (S_ISREG(st.st_mode))
> -		dtype = DT_REG;
> -	else if (S_ISDIR(st.st_mode))
> -		dtype = DT_DIR;
> -	else if (S_ISLNK(st.st_mode))
> -		dtype = DT_LNK;
> -
> -cleanup:
> -	strbuf_setlen(path, base_path_len);
> -	return dtype;
> -}
> -
>  static int count_files(struct strbuf *path)
>  {
>  	DIR *dir = opendir(path->buf);
> diff --git a/dir.c b/dir.c
> index 8486e4d56ff..5e01af3a25e 100644
> --- a/dir.c
> +++ b/dir.c
> @@ -2235,6 +2235,34 @@ static int get_index_dtype(struct index_state *istate,
>  	return DT_UNKNOWN;
>  }
>  
> +unsigned char get_dtype(struct dirent *e, struct strbuf *path)
> +{
> +	struct stat st;
> +	unsigned char dtype = DTYPE(e);
> +	size_t base_path_len;
> +
> +	if (dtype != DT_UNKNOWN)
> +		return dtype;
> +
> +	/* d_type unknown in dirent, try to fall back on lstat results */
> +	base_path_len = path->len;
> +	strbuf_addstr(path, e->d_name);
> +	if (lstat(path->buf, &st))
> +		goto cleanup;
> +
> +	/* determine d_type from st_mode */
> +	if (S_ISREG(st.st_mode))
> +		dtype = DT_REG;
> +	else if (S_ISDIR(st.st_mode))
> +		dtype = DT_DIR;
> +	else if (S_ISLNK(st.st_mode))
> +		dtype = DT_LNK;
> +
> +cleanup:
> +	strbuf_setlen(path, base_path_len);
> +	return dtype;
> +}
> +
>  static int resolve_dtype(int dtype, struct index_state *istate,
>  			 const char *path, int len)
>  {
> diff --git a/dir.h b/dir.h
> index ad06682fd54..28c630ce806 100644
> --- a/dir.h
> +++ b/dir.h
> @@ -363,6 +363,17 @@ struct dir_struct {
>  
>  struct dirent *readdir_skip_dot_and_dotdot(DIR *dirp);
>  
> +/*
> + * Get the d_type of a dirent. If the d_type is unknown, derive it from
> + * stat.st_mode using the path to the dirent's containing directory (path) and
> + * the name of the dirent itself.
> + *
> + * Note that 'path' is assumed to have a trailing slash. It is also modified
> + * in-place during the execution of the function, but is then reverted to its
> + * original value before returning.
> + */
> +unsigned char get_dtype(struct dirent *e, struct strbuf *path);
> +
>  /*Count the number of slashes for string s*/
>  int count_slashes(const char *s);