Re: [PATCH v2 02/20] dir: move doc to dir.h

> From: Heba Waly <heba.waly@gmail.com>
> 
> Move the documentation from Documentation/technical/api-directory-listing.txt
> to dir.h as it's easier for the developers to find the usage information
> beside the code instead of looking for it in another doc file.
> 
> Also documentation/technical/api-directory-listing.txt is removed because
> the information it has is now redundant and it'll be hard to keep it up to
> date and synchronized with the documentation in the header files.
> 
> Signed-off-by: Heba Waly <heba.waly@gmail.com>
> ---
>  .../technical/api-directory-listing.txt       | 130 ------------------
>  dir.h                                         | 118 +++++++++++++++-
>  2 files changed, 113 insertions(+), 135 deletions(-)
>  delete mode 100644 Documentation/technical/api-directory-listing.txt
> 
> diff --git a/Documentation/technical/api-directory-listing.txt b/Documentation/technical/api-directory-listing.txt
> deleted file mode 100644
> index 76b6e4f71b..0000000000
> --- a/Documentation/technical/api-directory-listing.txt
> +++ /dev/null
> @@ -1,130 +0,0 @@
> -directory listing API
> -=====================
> -
> -The directory listing API is used to enumerate paths in the work tree,
> -optionally taking `.git/info/exclude` and `.gitignore` files per
> -directory into account.
> -
> -Data structure
> ---------------
> -
> -`struct dir_struct` structure is used to pass directory traversal
> -options to the library and to record the paths discovered.  A single
> -`struct dir_struct` is used regardless of whether or not the traversal
> -recursively descends into subdirectories.
> -
> -The notable options are:
> -
> -`exclude_per_dir`::
> -
> -	The name of the file to be read in each directory for excluded
> -	files (typically `.gitignore`).
> -
> -`flags`::
> -
> -	A bit-field of options:
> -
> -`DIR_SHOW_IGNORED`:::
> -
> -	Return just ignored files in `entries[]`, not untracked
> -	files. This flag is mutually exclusive with
> -	`DIR_SHOW_IGNORED_TOO`.
> -
> -`DIR_SHOW_IGNORED_TOO`:::
> -
> -	Similar to `DIR_SHOW_IGNORED`, but return ignored files in
> -	`ignored[]` in addition to untracked files in
> -	`entries[]`. This flag is mutually exclusive with
> -	`DIR_SHOW_IGNORED`.
> -
> -`DIR_KEEP_UNTRACKED_CONTENTS`:::
> -
> -	Only has meaning if `DIR_SHOW_IGNORED_TOO` is also set; if this is set, the
> -	untracked contents of untracked directories are also returned in
> -	`entries[]`.
> -
> -`DIR_SHOW_IGNORED_TOO_MODE_MATCHING`:::
> -
> -	Only has meaning if `DIR_SHOW_IGNORED_TOO` is also set; if
> -	this is set, returns ignored files and directories that match
> -	an exclude pattern. If a directory matches an exclude pattern,
> -	then the directory is returned and the contained paths are
> -	not. A directory that does not match an exclude pattern will
> -	not be returned even if all of its contents are ignored. In
> -	this case, the contents are returned as individual entries.
> -+
> -If this is set, files and directories that explicitly match an ignore
> -pattern are reported. Implicitly ignored directories (directories that
> -do not match an ignore pattern, but whose contents are all ignored)
> -are not reported, instead all of the contents are reported.
> -
> -`DIR_COLLECT_IGNORED`:::
> -
> -	Special mode for git-add. Return ignored files in `ignored[]` and
> -	untracked files in `entries[]`. Only returns ignored files that match
> -	pathspec exactly (no wildcards). Does not recurse into ignored
> -	directories.
> -
> -`DIR_SHOW_OTHER_DIRECTORIES`:::
> -
> -	Include a directory that is not tracked.
> -
> -`DIR_HIDE_EMPTY_DIRECTORIES`:::
> -
> -	Do not include a directory that is not tracked and is empty.
> -
> -`DIR_NO_GITLINKS`:::
> -
> -	If set, recurse into a directory that looks like a Git
> -	directory.  Otherwise it is shown as a directory.
> -
> -The result of the enumeration is left in these fields:
> -
> -`entries[]`::
> -
> -	An array of `struct dir_entry`, each element of which describes
> -	a path.
> -
> -`nr`::
> -
> -	The number of members in `entries[]` array.
> -
> -`alloc`::
> -
> -	Internal use; keeps track of allocation of `entries[]` array.
> -
> -`ignored[]`::
> -
> -	An array of `struct dir_entry`, used for ignored paths with the
> -	`DIR_SHOW_IGNORED_TOO` and `DIR_COLLECT_IGNORED` flags.
> -
> -`ignored_nr`::
> -
> -	The number of members in `ignored[]` array.
> -
> -Calling sequence
> -----------------
> -
> -Note: index may be looked at for .gitignore files that are CE_SKIP_WORKTREE
> -marked. If you to exclude files, make sure you have loaded index first.
> -
> -* Prepare `struct dir_struct dir` and clear it with `memset(&dir, 0,
> -  sizeof(dir))`.
> -
> -* To add single exclude pattern, call `add_pattern_list()` and then
> -  `add_pattern()`.
> -
> -* To add patterns from a file (e.g. `.git/info/exclude`), call
> -  `add_patterns_from_file()` , and/or set `dir.exclude_per_dir`.  A
> -  short-hand function `setup_standard_excludes()` can be used to set
> -  up the standard set of exclude settings.
> -
> -* Set options described in the Data Structure section above.
> -
> -* Call `read_directory()`.
> -
> -* Use `dir.entries[]`.
> -
> -* Call `clear_directory()` when none of the contained elements are no longer in use.
> -
> -(JC)
> diff --git a/dir.h b/dir.h
> index 2fbdef014f..1b41d29c07 100644
> --- a/dir.h
> +++ b/dir.h
> @@ -1,11 +1,43 @@
>  #ifndef DIR_H
>  #define DIR_H
>  
> -/* See Documentation/technical/api-directory-listing.txt */
> -
>  #include "cache.h"
>  #include "strbuf.h"
>  
> +/**
> + * The directory listing API is used to enumerate paths in the work tree,
> + * optionally taking `.git/info/exclude` and `.gitignore` files per directory
> + * into account.
> + */
> +
> +/**
> + * Calling sequence
> + * ----------------
> + *
> + * Note: index may be looked at for .gitignore files that are CE_SKIP_WORKTREE
> + * marked. If you to exclude files, make sure you have loaded index first.

> + *
> + * - Prepare `struct dir_struct dir` and clear it with `memset(&dir, 0,
> + * sizeof(dir))`.
> + *
> + * - To add single exclude pattern, call `add_pattern_list()` and then
> + *   `add_pattern()`.
> + *
> + * - To add patterns from a file (e.g. `.git/info/exclude`), call
> + *   `add_patterns_from_file()` , and/or set `dir.exclude_per_dir`.  A
> + *   short-hand function `setup_standard_excludes()` can be used to set
> + *   up the standard set of exclude settings.
> + *
> + * - Set options described in the Data Structure section above.
> + *
> + * - Call `read_directory()`.
> + *
> + * - Use `dir.entries[]`.
> + *
> + * - Call `clear_directory()` when none of the contained elements are no longer in use.
> + *
> + */
> +
>  struct dir_entry {
>  	unsigned int len;
>  	char name[FLEX_ARRAY]; /* more */
> @@ -144,25 +176,101 @@ struct untracked_cache {
>  	unsigned int use_fsmonitor : 1;
>  };
>  
> +/**
> + * pass directory traversal options to the library and to record the paths
> + * discovered. A single `struct dir_struct` is used regardless of whether or
> + * not the traversal recursively descends into subdirectories.

> + */
>  struct dir_struct {
> -	int nr, alloc;
> -	int ignored_nr, ignored_alloc;
> +
> +    /* The number of members in `entries[]` array. */
> +    int nr;
> +
> +    /* Internal use; keeps track of allocation of `entries[]` array.*/
> +    int alloc;
> +
> +    /* The number of members in `ignored[]` array. */
> +	int ignored_nr;
> +
> +	int ignored_alloc;
> +
> +	/* bit-field of options */
>  	enum {
> +
> +	    /**
> +	     * Return just ignored files in `entries[]`, not untracked files.
> +	     * This flag is mutually exclusive with `DIR_SHOW_IGNORED_TOO`.
> +	     */

>  		DIR_SHOW_IGNORED = 1<<0,
> +
> +		/* Include a directory that is not tracked. */
>  		DIR_SHOW_OTHER_DIRECTORIES = 1<<1,
> +
> +		/* Do not include a directory that is not tracked and is empty. */
>  		DIR_HIDE_EMPTY_DIRECTORIES = 1<<2,
> +
> +		/**
> +		 * If set, recurse into a directory that looks like a Git directory.
> +		 * Otherwise it is shown as a directory.
> +		 */
>  		DIR_NO_GITLINKS = 1<<3,
> +
> +		/**
> +		 * Special mode for git-add. Return ignored files in `ignored[]` and
> +	     * untracked files in `entries[]`. Only returns ignored files that match
> +	     * pathspec exactly (no wildcards). Does not recurse into ignored
> +	     * directories.
> +		 */
>  		DIR_COLLECT_IGNORED = 1<<4,
> +
> +		/**
> +		 * Similar to `DIR_SHOW_IGNORED`, but return ignored files in
> +		 * `ignored[]` in addition to untracked files in `entries[]`.
> +		 * This flag is mutually exclusive with `DIR_SHOW_IGNORED`.
> +		 */
>  		DIR_SHOW_IGNORED_TOO = 1<<5,
> +
>  		DIR_COLLECT_KILLED_ONLY = 1<<6,
> +
> +        /**
> +         * Only has meaning if `DIR_SHOW_IGNORED_TOO` is also set; if this is
> +         * set, the untracked contents of untracked directories are also
> +         * returned in `entries[]`.
> +         */
>  		DIR_KEEP_UNTRACKED_CONTENTS = 1<<7,
> +
> +		/**
> +		 * Only has meaning if `DIR_SHOW_IGNORED_TOO` is also set; if this is
> +		 * set, returns ignored files and directories that match an exclude
> +		 * pattern. If a directory matches an exclude pattern, then the
> +		 * directory is returned and the contained paths are not. A directory
> +		 * that does not match an exclude pattern will not be returned even if
> +		 * all of its contents are ignored. In this case, the contents are
> +		 * returned as individual entries.
> +		 *
> +		 * If this is set, files and directories that explicitly match an ignore
> +         * pattern are reported. Implicitly ignored directories (directories that
> +         * do not match an ignore pattern, but whose contents are all ignored)
> +         * are not reported, instead all of the contents are reported.
> +		 */
>  		DIR_SHOW_IGNORED_TOO_MODE_MATCHING = 1<<8,
> +
>  		DIR_SKIP_NESTED_GIT = 1<<9
>  	} flags;
> +
> +	/* An array of `struct dir_entry`, each element of which describes a path. */
>  	struct dir_entry **entries;
> +
> +	/**
> +	 * used for ignored paths with the `DIR_SHOW_IGNORED_TOO` and
> +	 * `DIR_COLLECT_IGNORED` flags.
> +	 */
>  	struct dir_entry **ignored;
>  
> -	/* Exclude info */
> +	/**
> +	 * The name of the file to be read in each directory for excluded files
> +	 * (typically `.gitignore`).
> +	 */
>  	const char *exclude_per_dir;
>  
>  	/*
> -- 
> gitgitgadget
>