.\"	$Id: mandoc_headers.3,v 1.34 2021/08/10 12:55:03 schwarze Exp $
.\"
.\" Copyright (c) 2014-2021 Ingo Schwarze <schwarze@openbsd.org>
.\"
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.Dd $Mdocdate: August 10 2021 $
.Dt MANDOC_HEADERS 3
.Os
.Sh NAME
.Nm mandoc_headers
.Nd ordering of mandoc include files
.Sh DESCRIPTION
To support a cleaner coding style, the mandoc header files do not
contain any include directives and do not guard against multiple
inclusion.
The application developer has to make sure that the headers are
included in a proper order, and that no header is included more
than once.
.Pp
The headers and functions form three major groups:
.Sx Parser interface ,
.Sx Parser internals ,
and
.Sx Formatter interface .
.Pp
Various rules are given below prohibiting the inclusion of certain
combinations of headers into the same file.
The intention is to keep the following functional components
separate from each other:
.Pp
.Bl -dash -offset indent -compact
.It
.Xr roff 7
parser
.It
.Xr mdoc 7
parser
.It
.Xr man 7
parser
.It
.Xr tbl 7
parser
.It
.Xr eqn 7
parser
.It
terminal formatters
.It
HTML formatters
.It
search tools
.It
main programs
.El
.Pp
Note that mere usage of an opaque struct type does
.Em not
require inclusion of the header where that type is defined.
.Ss Parser interface
Each of the following headers can be included without including
any other mandoc header.
These headers should be included before any other mandoc headers.
.Bl -tag -width Ds
.It Qq Pa mandoc_aux.h
Memory allocation utility functions; can be used everywhere.
.Pp
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides the functions documented in
.Xr mandoc_malloc 3 .
.It Qq Pa mandoc_ohash.h
Hashing utility functions; can be used everywhere.
.Pp
Requires
.In stddef.h
for
.Vt ptrdiff_t
and
.In stdint.h
for
.Vt uint32_t .
.Pp
Includes
.In ohash.h
and provides
.Fn mandoc_ohash_init .
.It Qq Pa mandoc.h
Error handling, escape sequence, and character utilities;
can be used everywhere.
.Pp
Requires
.In sys/types.h
for
.Vt size_t
and
.In stdio.h
for
.Vt FILE .
.Pp
Provides
.Vt enum mandoc_esc ,
.Vt enum mandocerr ,
.Vt enum mandoclevel ,
the function
.Xr mandoc_escape 3 ,
the functions described in
.Xr mchars_alloc 3 ,
and the
.Fn mandoc_msg*
functions.
.It Qq Pa roff.h
Common data types for all syntax trees and related functions;
can be used everywhere.
.Pp
Provides
.Vt enum mandoc_os ,
.Vt enum mdoc_endbody ,
.Vt enum roff_macroset ,
.Vt enum roff_sec ,
.Vt enum roff_tok ,
.Vt enum roff_type ,
.Vt struct roff_man ,
.Vt struct roff_meta ,
.Vt struct roff_node ,
the constant array
.Va roff_name
and the function
.Fn deroff .
.Pp
Uses pointers to the types
.Vt struct ohash
from
.Qq Pa mandoc_ohash.h ,
.Vt struct mdoc_arg
and
.Vt union mdoc_data
from
.Qq Pa mdoc.h ,
.Vt struct tbl_span
from
.Qq Pa tbl.h ,
and
.Vt struct eqn_box
from
.Qq Pa eqn.h
as opaque struct members.
.It Qq Pa tbl.h
Data structures for the
.Xr tbl 7
parse tree; can be used everywhere.
.Pp
Requires
.In sys/types.h
for
.Vt size_t
and
.Qq Pa mandoc.h
for
.Vt enum mandoc_esc .
.Pp
Provides
.Vt enum tbl_cellt ,
.Vt enum tbl_datt ,
.Vt enum tbl_spant ,
.Vt struct tbl_opts ,
.Vt struct tbl_cell ,
.Vt struct tbl_row ,
.Vt struct tbl_dat ,
and
.Vt struct tbl_span .
.It Qq Pa eqn.h
Data structures for the
.Xr eqn 7
parse tree; can be used everywhere.
.Pp
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides
.Vt enum eqn_boxt ,
.Vt enum eqn_fontt ,
.Vt enum eqn_post ,
and
.Vt struct eqn_box .
.It Qq Pa mandoc_parse.h
Top level parser interface, for use in the main program
and in the main parser, but not in formatters.
.Pp
Requires
.Qq Pa mandoc.h
for
.Vt enum mandocerr
and
.Vt enum mandoclevel
and
.Qq Pa roff.h
for
.Vt enum mandoc_os .
.Pp
Uses the opaque type
.Vt struct mparse
from
.Pa read.c
for function prototypes.
Uses
.Vt struct roff_meta
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.It Qq Pa mandoc_xr.h
Cross reference validation; intended for use in the main program
and in parsers, but not in formatters.
.Pp
Provides
.Vt struct mandoc_xr
and the functions
.Fn mandoc_xr_reset ,
.Fn mandoc_xr_add ,
.Fn mandoc_xr_get ,
and
.Fn mandoc_xr_free .
.It Qq Pa tag.h
Internal interfaces to tag syntax tree nodes,
for use by validation modules only.
.Pp
Requires
.In limits.h
for
.Dv INT_MAX .
.Pp
Provides the functions
.Fn tag_alloc ,
.Fn tag_put ,
.Fn tag_check ,
and
.Fn tag_free
and some
.Dv TAG_*
constants.
.Pp
Uses the type
.Vt struct roff_node
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.El
.Pp
The following two require
.Qq Pa roff.h
but no other mandoc headers.
Afterwards, any other mandoc headers can be included as needed.
.Bl -tag -width Ds
.It Qq Pa mdoc.h
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides
.Vt enum mdocargt ,
.Vt enum mdoc_auth ,
.Vt enum mdoc_disp ,
.Vt enum mdoc_font ,
.Vt enum mdoc_list ,
.Vt struct mdoc_argv ,
.Vt struct mdoc_arg ,
.Vt struct mdoc_an ,
.Vt struct mdoc_bd ,
.Vt struct mdoc_bf ,
.Vt struct mdoc_bl ,
.Vt struct mdoc_rs ,
.Vt union mdoc_data ,
and the functions
.Fn mdoc_*
described in
.Xr mandoc 3 .
.Pp
Uses the types
.Vt struct roff_node
from
.Qq Pa roff.h
and
.Vt struct roff_man
from
.Qq Pa roff_int.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
internals of different parsers.
.It Qq Pa man.h
Provides the functions
.Fn man_*
described in
.Xr mandoc 3 .
.Pp
Uses the type
.Vt struct roff_man
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.Pp
When this header is included, the same file should not include
internals of different parsers.
.El
.Ss Parser internals
Most of the following headers require inclusion of a parser interface header
before they can be included.
All parser interface headers should precede all parser internal headers.
When any parser internal headers are included, the same file should
not include any formatter headers.
.Bl -tag -width Ds
.It Qq Pa libmandoc.h
Requires
.In sys/types.h
for
.Vt size_t
and
.Qq Pa mandoc.h
for
.Vt enum mandocerr .
.Pp
Provides
.Vt struct buf ,
utility functions needed by multiple parsers,
and the top-level functions to call the parsers.
.Pp
Uses the opaque type
.Vt struct roff
from
.Pa roff.c
for function prototypes.
Uses the type
.Vt struct roff_man
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.It Qq Pa roff_int.h
Parser internals shared by multiple parsers.
Can be used in all parsers, but not in main programs or formatters.
.Pp
Requires
.Qq Pa roff.h
for
.Vt enum roff_type
and
.Vt enum roff_tok .
.Pp
Provides
.Vt enum roff_next ,
.Vt struct roff_man ,
functions named
.Fn roff_*
to handle roff nodes,
.Fn roffhash_alloc ,
.Fn roffhash_find ,
.Fn roffhash_free ,
and
.Fn roff_validate ,
and the two special functions
.Fn man_breakscope
and
.Fn mdoc_argv_free
because the latter two are needed by
.Pa roff.c .
.Pp
Uses the types
.Vt struct ohash
from
.Qq Pa mandoc_ohash.h ,
.Vt struct roff_node
and
.Vt struct roff_meta
from
.Qq Pa roff.h ,
.Vt struct roff
from
.Pa roff.c ,
and
.Vt struct mdoc_arg
from
.Qq Pa mdoc.h
as opaque types for function prototypes.
.It Qq Pa libmdoc.h
Requires
.Qq Pa roff.h
for
.Vt enum roff_tok
and
.Vt enum roff_sec .
.Pp
Provides
.Vt enum margserr ,
.Vt enum mdelim ,
.Vt struct mdoc_macro ,
and many functions internal to the
.Xr mdoc 7
parser.
.Pp
Uses the types
.Vt struct roff_node
from
.Qq Pa roff.h ,
.Vt struct roff_man
from
.Qq Pa roff_int.h ,
and
.Vt struct mdoc_arg
from
.Qq Pa mdoc.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
interfaces of different parsers.
.It Qq Pa libman.h
Requires
.Qq Pa roff.h
for
.Vt enum roff_tok .
.Pp
Provides
.Vt struct man_macro
and some functions internal to the
.Xr man 7
parser.
.Pp
Uses the types
.Vt struct roff_node
from
.Qq Pa roff.h
and
.Vt struct roff_man
from
.Qq Pa roff_int.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
interfaces of different parsers.
.It Qq Pa eqn_parse.h
External interface of the
.Xr eqn 7
parser, for use in the
.Xr roff 7
and
.Xr eqn 7
parsers only.
.Pp
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides
.Vt struct eqn_node
and the functions
.Fn eqn_alloc ,
.Fn eqn_box_new ,
.Fn eqn_box_free ,
.Fn eqn_free ,
.Fn eqn_parse ,
.Fn eqn_read ,
and
.Fn eqn_reset .
.Pp
Uses the type
.Vt struct eqn_box
from
.Qq Pa mandoc.h
as an opaque type for function prototypes.
Uses the types
.Vt struct roff_node
from
.Qq Pa roff.h
and
.Vt struct eqn_def
from
.Pa eqn.c
as opaque struct members.
.Pp
When this header is included, the same file should not include
internals of different parsers.
.It Qq Pa tbl_parse.h
External interface of the
.Xr tbl 7
parser, for use in the
.Xr roff 7
and
.Xr tbl 7
parsers only.
.Pp
Provides the functions documented in
.Xr tbl 3 .
.Pp
Uses the types
.Vt struct tbl_span
from
.Qq Pa tbl.h
and
.Vt struct tbl_node
from
.Qq Pa tbl_int.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
internals of different parsers.
.It Qq Pa tbl_int.h
Internal interfaces of the
.Xr tbl 7
parser, for use inside the
.Xr tbl 7
parser only.
.Pp
Requires
.Qq Pa tbl.h
for
.Vt struct tbl_opts .
.Pp
Provides
.Vt enum tbl_part ,
.Vt struct tbl_node ,
and the functions
.Fn tbl_option ,
.Fn tbl_layout ,
.Fn tbl_data ,
.Fn tbl_cdata ,
and
.Fn tbl_reset .
.Pp
When this header is included, the same file should not include
interfaces of different parsers.
.El
.Ss Formatter interface
These headers should be included after any parser interface headers.
No parser internal headers should be included by the same file.
.Bl -tag -width Ds
.It Qq Pa out.h
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides
.Vt enum roffscale ,
.Vt struct roffcol ,
.Vt struct roffsu ,
.Vt struct rofftbl ,
.Fn a2roffsu ,
and
.Fn tblcalc .
.Pp
Uses
.Vt struct tbl_span
from
.Qq Pa mandoc.h
as an opaque type for function prototypes.
.Pp
When this header is included, the same file should not include
.Qq Pa mansearch.h .
.It Qq Pa term.h
Requires
.In sys/types.h
for
.Vt size_t
and
.Qq Pa out.h
for
.Vt struct roffsu
and
.Vt struct rofftbl .
.Pp
Provides
.Vt enum termenc ,
.Vt enum termfont ,
.Vt enum termtype ,
.Vt struct termp_tbl ,
.Vt struct termp ,
.Fn roff_term_pre ,
and many terminal formatting functions.
.Pp
Uses the opaque type
.Vt struct termp_ps
from
.Pa term_ps.c .
Uses
.Vt struct tbl_span
and
.Vt struct eqn_box
from
.Qq Pa mandoc.h
and
.Vt struct roff_meta
and
.Vt struct roff_node
from
.Qq Pa roff.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
.Qq Pa html.h
or
.Qq Pa mansearch.h .
.It Qq Pa tag_term.h
Requires
.In sys/types.h
for
.Vt size_t
and
.In stdio.h
for
.Vt FILE .
.Pp
Provides an interface to generate
.Xr ctags 1
files for the
.Ic :t
functionality mentioned in
.Xr man 1 .
.Pp
Uses the type
.Vt struct roff_node
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.Pp
When this header is included, the same file should not include
.Qq Pa html.h
or
.Qq Pa mansearch.h .
.It Qq Pa html.h
Requires
.In sys/types.h
for
.Vt size_t ,
.Qq Pa mandoc.h
for
.Vt enum mandoc_esc ,
.Qq Pa roff.h
for
.Vt enum roff_tok ,
and
.Qq Pa out.h
for
.Vt struct roffsu
and
.Vt struct rofftbl .
.Pp
Provides
.Vt enum htmltag ,
.Vt enum htmlattr ,
.Vt enum htmlfont ,
.Vt struct tag ,
.Vt struct tagq ,
.Vt struct htmlpair ,
.Vt struct html ,
.Fn roff_html_pre ,
and many HTML formatting functions.
.Pp
Uses
.Vt struct tbl_span
and
.Vt struct eqn_box
from
.Qq Pa mandoc.h
and
.Vt struct roff_node
from
.Qq Pa roff.h
as opaque types for function prototypes.
.Pp
When this header is included, the same file should not include
.Qq Pa term.h ,
.Qq Pa tab_term.h ,
or
.Qq Pa mansearch.h .
.It Qq Pa main.h
Provides the top level steering functions for all formatters.
.Pp
Uses the type
.Vt struct roff_meta
from
.Qq Pa roff.h
as an opaque type for function prototypes.
.It Qq Pa manconf.h
Requires
.In sys/types.h
for
.Vt size_t .
.Pp
Provides
.Vt struct manconf ,
.Vt struct manpaths ,
.Vt struct manoutput ,
and the functions
.Fn manconf_parse ,
.Fn manconf_output ,
.Fn manconf_free ,
and
.Fn manpath_base .
.It Qq Pa mansearch.h
Requires
.In sys/types.h
for
.Vt size_t
and
.In stdint.h
for
.Vt uint64_t .
.Pp
Provides
.Vt enum argmode ,
.Vt struct manpage ,
.Vt struct mansearch ,
and the functions
.Fn mansearch
and
.Fn mansearch_free .
.Pp
Uses
.Vt struct manpaths
from
.Qq Pa manconf.h
as an opaque type for function prototypes.
.Pp
When this header is included, the same file should not include
.Qq Pa out.h ,
.Qq Pa term.h ,
.Qq Pa tab_term.h ,
or
.Qq Pa html.h .
.El