Revert merging of {mdoc,man}.h -> mandoc.h.

While I'm add it, properly document all structures in these files.

3 files changed, 506 insertions, 415 deletions

diff --git a/man.h b/man.h
index a7181f5f..4de03fbf 100644
--- a/man.h
+++ b/man.h
@@ -17,8 +17,100 @@
 #ifndef MAN_H
 #define MAN_H
 
-#include <time.h>
+/* 
+ * What follows is a list of ALL possible macros. 
+ */
+enum	mant {
+	MAN_br = 0,
+	MAN_TH,
+	MAN_SH,
+	MAN_SS,
+	MAN_TP,
+	MAN_LP,
+	MAN_PP,
+	MAN_P,
+	MAN_IP,
+	MAN_HP,
+	MAN_SM,
+	MAN_SB,
+	MAN_BI,
+	MAN_IB,
+	MAN_BR,
+	MAN_RB,
+	MAN_R,
+	MAN_B,
+	MAN_I,
+	MAN_IR,
+	MAN_RI,
+	MAN_na,
+	MAN_i,
+	MAN_sp,
+	MAN_nf,
+	MAN_fi,
+	MAN_r,
+	MAN_RE,
+	MAN_RS,
+	MAN_DT,
+	MAN_UC,
+	MAN_PD,
+	MAN_Sp,
+	MAN_Vb,
+	MAN_Ve,
+	MAN_AT,
+	MAN_in,
+	MAN_MAX
+};
+
+/* 
+ * Type of a syntax node. 
+ */
+enum	man_type {
+	MAN_TEXT,
+	MAN_ELEM,
+	MAN_ROOT,
+	MAN_BLOCK,
+	MAN_HEAD,
+	MAN_BODY
+};
+
+/* 
+ * Information from prologue. 
+ */
+struct	man_meta {
+	char		*msec; /* `TH' section (1, 3p, etc.) */
+	time_t		 date; /* `TH' normalised date */
+	char		*rawdate; /* raw `TH' date */
+	char		*vol; /* `TH' volume */
+	char		*title; /* `TH' title (e.g., FOO) */
+	char		*source; /* `TH' source (e.g., GNU) */
+};
 
+/* 
+ * Single node in tree-linked AST. 
+ */
+struct	man_node {
+	struct man_node	*parent; /* parent AST node */
+	struct man_node	*child; /* first child AST node */
+	struct man_node	*next; /* sibling AST node */
+	struct man_node	*prev; /* prior sibling AST node */
+	int		 nchild; /* number children */
+	int		 line;
+	int		 pos;
+	enum mant	 tok; /* tok or MAN__MAX if none */
+	int		 flags;
+#define	MAN_VALID	(1 << 0) /* has been validated */
+#define	MAN_ACTED	(1 << 1) /* has been acted upon */
+#define	MAN_EOS		(1 << 2) /* at sentence boundary */
+	enum man_type	 type; /* AST node type */
+	char		*string; /* TEXT node argument */
+	struct man_node	*head; /* BLOCK node HEAD ptr */
+	struct man_node	*body; /* BLOCK node BODY ptr */
+};
+
+/*
+ * Names of macros.  Index is enum mant.  Indexing into this returns
+ * the normalised name, e.g., man_macronames[MAN_SH] -> "SH".
+ */
 extern	const char *const *man_macronames;
 
 __BEGIN_DECLS
diff --git a/mandoc.h b/mandoc.h
index d417c335..77b23b97 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -20,19 +20,27 @@
 #define ASCII_NBRSP	 31  /* non-breaking space */
 #define	ASCII_HYPH	 30  /* breakable hyphen */
 
-__BEGIN_DECLS
-
+/*
+ * Status level.  This refers to both internal status (i.e., whilst
+ * running, when warnings/errors are reported) and an indicator of a
+ * threshold of when to halt (when said internal state exceeds the
+ * threshold).
+ */
 enum	mandoclevel {
 	MANDOCLEVEL_OK = 0,
 	MANDOCLEVEL_RESERVED,
-	MANDOCLEVEL_WARNING,
-	MANDOCLEVEL_ERROR,
-	MANDOCLEVEL_FATAL,
-	MANDOCLEVEL_BADARG,
-	MANDOCLEVEL_SYSERR,
+	MANDOCLEVEL_WARNING, /* warnings: syntax, whitespace, etc. */
+	MANDOCLEVEL_ERROR, /* input has been thrown away */
+	MANDOCLEVEL_FATAL, /* input is borked */
+	MANDOCLEVEL_BADARG, /* bad argument in invocation */
+	MANDOCLEVEL_SYSERR, /* system error */
 	MANDOCLEVEL_MAX
 };
 
+/*
+ * All possible things that can go wrong within a parse, be it libroff,
+ * libmdoc, or libman.
+ */
 enum	mandocerr {
 	MANDOCERR_OK,
 
@@ -113,406 +121,20 @@ enum	mandocerr {
 	MANDOCERR_MAX
 };
 
+/*
+ * Available registers (set in libroff, accessed elsewhere).
+ */
 enum	regs {
-	REG_nS = 0,	/* register: nS */
+	REG_nS = 0,
 	REG__MAX
 };
 
-enum	mant {
-	MAN_br = 0,
-	MAN_TH,
-	MAN_SH,
-	MAN_SS,
-	MAN_TP,
-	MAN_LP,
-	MAN_PP,
-	MAN_P,
-	MAN_IP,
-	MAN_HP,
-	MAN_SM,
-	MAN_SB,
-	MAN_BI,
-	MAN_IB,
-	MAN_BR,
-	MAN_RB,
-	MAN_R,
-	MAN_B,
-	MAN_I,
-	MAN_IR,
-	MAN_RI,
-	MAN_na,
-	MAN_i,
-	MAN_sp,
-	MAN_nf,
-	MAN_fi,
-	MAN_r,
-	MAN_RE,
-	MAN_RS,
-	MAN_DT,
-	MAN_UC,
-	MAN_PD,
-	MAN_Sp,
-	MAN_Vb,
-	MAN_Ve,
-	MAN_AT,
-	MAN_in,
-	MAN_MAX
-};
-
-enum	man_type {
-	MAN_TEXT,
-	MAN_ELEM,
-	MAN_ROOT,
-	MAN_BLOCK,
-	MAN_HEAD,
-	MAN_BODY
-};
-
-enum	mdoct {
-	MDOC_Ap = 0,
-	MDOC_Dd,
-	MDOC_Dt,
-	MDOC_Os,
-	MDOC_Sh,
-	MDOC_Ss,
-	MDOC_Pp,
-	MDOC_D1,
-	MDOC_Dl,
-	MDOC_Bd,
-	MDOC_Ed,
-	MDOC_Bl,
-	MDOC_El,
-	MDOC_It,
-	MDOC_Ad,
-	MDOC_An,
-	MDOC_Ar,
-	MDOC_Cd,
-	MDOC_Cm,
-	MDOC_Dv,
-	MDOC_Er,
-	MDOC_Ev,
-	MDOC_Ex,
-	MDOC_Fa,
-	MDOC_Fd,
-	MDOC_Fl,
-	MDOC_Fn,
-	MDOC_Ft,
-	MDOC_Ic,
-	MDOC_In,
-	MDOC_Li,
-	MDOC_Nd,
-	MDOC_Nm,
-	MDOC_Op,
-	MDOC_Ot,
-	MDOC_Pa,
-	MDOC_Rv,
-	MDOC_St,
-	MDOC_Va,
-	MDOC_Vt,
-	MDOC_Xr,
-	MDOC__A,
-	MDOC__B,
-	MDOC__D,
-	MDOC__I,
-	MDOC__J,
-	MDOC__N,
-	MDOC__O,
-	MDOC__P,
-	MDOC__R,
-	MDOC__T,
-	MDOC__V,
-	MDOC_Ac,
-	MDOC_Ao,
-	MDOC_Aq,
-	MDOC_At,
-	MDOC_Bc,
-	MDOC_Bf,
-	MDOC_Bo,
-	MDOC_Bq,
-	MDOC_Bsx,
-	MDOC_Bx,
-	MDOC_Db,
-	MDOC_Dc,
-	MDOC_Do,
-	MDOC_Dq,
-	MDOC_Ec,
-	MDOC_Ef,
-	MDOC_Em,
-	MDOC_Eo,
-	MDOC_Fx,
-	MDOC_Ms,
-	MDOC_No,
-	MDOC_Ns,
-	MDOC_Nx,
-	MDOC_Ox,
-	MDOC_Pc,
-	MDOC_Pf,
-	MDOC_Po,
-	MDOC_Pq,
-	MDOC_Qc,
-	MDOC_Ql,
-	MDOC_Qo,
-	MDOC_Qq,
-	MDOC_Re,
-	MDOC_Rs,
-	MDOC_Sc,
-	MDOC_So,
-	MDOC_Sq,
-	MDOC_Sm,
-	MDOC_Sx,
-	MDOC_Sy,
-	MDOC_Tn,
-	MDOC_Ux,
-	MDOC_Xc,
-	MDOC_Xo,
-	MDOC_Fo,
-	MDOC_Fc,
-	MDOC_Oo,
-	MDOC_Oc,
-	MDOC_Bk,
-	MDOC_Ek,
-	MDOC_Bt,
-	MDOC_Hf,
-	MDOC_Fr,
-	MDOC_Ud,
-	MDOC_Lb,
-	MDOC_Lp,
-	MDOC_Lk,
-	MDOC_Mt,
-	MDOC_Brq,
-	MDOC_Bro,
-	MDOC_Brc,
-	MDOC__C,
-	MDOC_Es,
-	MDOC_En,
-	MDOC_Dx,
-	MDOC__Q,
-	MDOC_br,
-	MDOC_sp,
-	MDOC__U,
-	MDOC_Ta,
-	MDOC_MAX
-};
-
-enum	mdocargt {
-	MDOC_Split,
-	MDOC_Nosplit,
-	MDOC_Ragged,
-	MDOC_Unfilled,
-	MDOC_Literal,
-	MDOC_File,
-	MDOC_Offset,
-	MDOC_Bullet,
-	MDOC_Dash,
-	MDOC_Hyphen,
-	MDOC_Item,
-	MDOC_Enum,
-	MDOC_Tag,
-	MDOC_Diag,
-	MDOC_Hang,
-	MDOC_Ohang,
-	MDOC_Inset,
-	MDOC_Column,
-	MDOC_Width,
-	MDOC_Compact,
-	MDOC_Std,
-	MDOC_Filled,
-	MDOC_Words,
-	MDOC_Emphasis,
-	MDOC_Symbolic,
-	MDOC_Nested,
-	MDOC_Centred,
-	MDOC_ARG_MAX
-};
-
-enum	mdoc_type {
-	MDOC_TEXT,
-	MDOC_ELEM,
-	MDOC_HEAD,
-	MDOC_TAIL,
-	MDOC_BODY,
-	MDOC_BLOCK,
-	MDOC_ROOT
-};
-
-enum	mdoc_sec {
-	SEC_NONE,
-	SEC_NAME,
-	SEC_LIBRARY,
-	SEC_SYNOPSIS,
-	SEC_DESCRIPTION,
-	SEC_IMPLEMENTATION,
-	SEC_RETURN_VALUES,
-	SEC_ENVIRONMENT, 
-	SEC_FILES,
-	SEC_EXIT_STATUS,
-	SEC_EXAMPLES,
-	SEC_DIAGNOSTICS,
-	SEC_COMPATIBILITY,
-	SEC_ERRORS,
-	SEC_SEE_ALSO,
-	SEC_STANDARDS,
-	SEC_HISTORY,
-	SEC_AUTHORS,
-	SEC_CAVEATS,
-	SEC_BUGS,
-	SEC_SECURITY,
-	SEC_CUSTOM,
-	SEC__MAX
-};
-
-enum	mdoc_endbody {
-	ENDBODY_NOT = 0,
-	ENDBODY_SPACE,
-	ENDBODY_NOSPACE
-};
-
-enum	mdoc_list {
-	LIST__NONE = 0,
-	LIST_bullet,
-	LIST_column,
-	LIST_dash,
-	LIST_diag,
-	LIST_enum,
-	LIST_hang,
-	LIST_hyphen,
-	LIST_inset,
-	LIST_item,
-	LIST_ohang,
-	LIST_tag
-};
-
-enum	mdoc_disp {
-	DISP__NONE = 0,
-	DISP_centred,
-	DISP_ragged,
-	DISP_unfilled,
-	DISP_filled,
-	DISP_literal
-};
-
-enum	mdoc_auth {
-	AUTH__NONE = 0,
-	AUTH_split,
-	AUTH_nosplit
-};
-
-enum	mdoc_font {
-	FONT__NONE = 0,
-	FONT_Em,
-	FONT_Li,
-	FONT_Sy
-};
-
-struct	man_meta {
-	char		*msec; /* `TH' section (e.g., 1--9) */
-	time_t		 date; /* parsed `TH' date */
-	char		*rawdate; /* raw `TH' date */
-	char		*vol; /* `TH' volume (e.g., KM) */
-	char		*title; /* `TH' title (e.g., LS, CAT) */
-	char		*source; /* `TH' source (e.g., GNU) */
-};
-
-struct	man_node {
-	struct man_node	*parent;
-	struct man_node	*child;
-	struct man_node	*next;
-	struct man_node	*prev;
-	int		 nchild;
-	int		 line;
-	int		 pos;
-	enum mant	 tok;
-	int		 flags;
-#define	MAN_VALID	(1 << 0)
-#define	MAN_ACTED	(1 << 1)
-#define	MAN_EOS		(1 << 2)
-	enum man_type	 type;
-	char		*string;
-	struct man_node	*head;
-	struct man_node	*body;
-};
-
-struct	mdoc_meta {
-	char		 *msec; /* `Dt' section (e.g., 1--9) */
-	char		 *vol; /* `Dt' volume (e.g., LOCAL) */
-	char		 *arch; /* `Dt' architecture (e.g., i386) */
-	time_t		  date; /* `Dd' date */
-	char		 *title; /* `Dt' title (e.g., LS, CAT) */
-	char		 *os; /* `Os' system (e.g., OpenBSD) */
-	char		 *name; /* leading `Nm' (e.g., ls, cat) */
-};
-
-struct	mdoc_argv {
-	enum mdocargt  	  arg;
-	int		  line;
-	int		  pos;
-	size_t		  sz;
-	char		**value;
-};
-
-struct 	mdoc_arg {
-	size_t		  argc;
-	struct mdoc_argv *argv;
-	unsigned int	  refcnt;
-};
-
-
-struct	mdoc_bd {
-	const char	 *offs; /* -offset */
-	enum mdoc_disp	  type; /* -ragged, etc. */
-	int		  comp; /* -compact */
-};
-
-struct	mdoc_bl {
-	const char	 *width; /* -width */
-	const char	 *offs; /* -offset */
-	enum mdoc_list	  type; /* -tag, -enum, etc. */
-	int		  comp; /* -compact */
-	size_t		  ncols; /* -column arg count */
-	const char	**cols; /* -column val ptr */
-};
-
-struct	mdoc_bf {
-	enum mdoc_font	  font; /* font */
-};
-
-struct	mdoc_an {
-	enum mdoc_auth	  auth; /* -split, etc. */
-};
-
-struct	mdoc_node {
-	struct mdoc_node *parent; /* parent AST node */
-	struct mdoc_node *child; /* first child AST node */
-	struct mdoc_node *next; /* sibling AST node */
-	struct mdoc_node *prev; /* prior sibling AST node */
-	int		  nchild; /* number children */
-	int		  line; /* parse line */
-	int		  pos; /* parse column */
-	enum mdoct	  tok; /* tok or MDOC__MAX if none */
-	int		  flags;
-#define	MDOC_VALID	 (1 << 0) /* has been validated */
-#define	MDOC_ACTED	 (1 << 1) /* has been acted upon */
-#define	MDOC_EOS	 (1 << 2) /* at sentence boundary */
-#define	MDOC_LINE	 (1 << 3) /* first macro/text on line */
-#define	MDOC_SYNPRETTY	 (1 << 4) /* SYNOPSIS-style formatting */
-#define	MDOC_ENDED	 (1 << 5) /* rendering has been ended */
-	enum mdoc_type	  type; /* AST node type */
-	enum mdoc_sec	  sec; /* current named section */
-	/* XXX: these can be union'd to shave a few bytes. */
-	struct mdoc_arg	 *args; 	/* BLOCK/ELEM */
-	struct mdoc_node *pending;	/* BLOCK */
-	struct mdoc_node *head;		/* BLOCK */
-	struct mdoc_node *body;		/* BLOCK */
-	struct mdoc_node *tail;		/* BLOCK */
-	char		 *string;	/* TEXT */
-	enum mdoc_endbody end;		/* BODY */
-
-	union {
-		struct mdoc_an  An;
-		struct mdoc_bd *Bd;
-		struct mdoc_bf *Bf;
-		struct mdoc_bl *Bl;
-	} data;
+/*
+ * A register (struct reg) can consist of many types: this consists of
+ * normalised types from the original string form.
+ */
+union	regval {
+	unsigned  u; /* unsigned integer */
 };
 
 /*
@@ -523,9 +145,7 @@ struct	mdoc_node {
  */
 struct	reg {
 	int		  set; /* whether set or not */
-	union {
-		unsigned  u; /* unsigned integer */
-	} v;
+	union regval	  v; /* parsed data */
 };
 
 /*
@@ -537,6 +157,8 @@ struct	regset {
 	struct reg	  regs[REG__MAX];
 };
 
+__BEGIN_DECLS
+
 /*
  * Callback function for warnings, errors, and fatal errors as they
  * occur in the compilers libroff, libmdoc, and libman.
diff --git a/mdoc.h b/mdoc.h
index 02f40c27..0e494f83 100644
--- a/mdoc.h
+++ b/mdoc.h
@@ -17,25 +17,402 @@
 #ifndef MDOC_H
 #define MDOC_H
 
+/* 
+ * What follows is a list of ALL possible macros. 
+ */
+enum	mdoct {
+	MDOC_Ap = 0,
+	MDOC_Dd,
+	MDOC_Dt,
+	MDOC_Os,
+	MDOC_Sh,
+	MDOC_Ss,
+	MDOC_Pp,
+	MDOC_D1,
+	MDOC_Dl,
+	MDOC_Bd,
+	MDOC_Ed,
+	MDOC_Bl,
+	MDOC_El,
+	MDOC_It,
+	MDOC_Ad,
+	MDOC_An,
+	MDOC_Ar,
+	MDOC_Cd,
+	MDOC_Cm,
+	MDOC_Dv,
+	MDOC_Er,
+	MDOC_Ev,
+	MDOC_Ex,
+	MDOC_Fa,
+	MDOC_Fd,
+	MDOC_Fl,
+	MDOC_Fn,
+	MDOC_Ft,
+	MDOC_Ic,
+	MDOC_In,
+	MDOC_Li,
+	MDOC_Nd,
+	MDOC_Nm,
+	MDOC_Op,
+	MDOC_Ot,
+	MDOC_Pa,
+	MDOC_Rv,
+	MDOC_St,
+	MDOC_Va,
+	MDOC_Vt,
+	MDOC_Xr,
+	MDOC__A,
+	MDOC__B,
+	MDOC__D,
+	MDOC__I,
+	MDOC__J,
+	MDOC__N,
+	MDOC__O,
+	MDOC__P,
+	MDOC__R,
+	MDOC__T,
+	MDOC__V,
+	MDOC_Ac,
+	MDOC_Ao,
+	MDOC_Aq,
+	MDOC_At,
+	MDOC_Bc,
+	MDOC_Bf,
+	MDOC_Bo,
+	MDOC_Bq,
+	MDOC_Bsx,
+	MDOC_Bx,
+	MDOC_Db,
+	MDOC_Dc,
+	MDOC_Do,
+	MDOC_Dq,
+	MDOC_Ec,
+	MDOC_Ef,
+	MDOC_Em,
+	MDOC_Eo,
+	MDOC_Fx,
+	MDOC_Ms,
+	MDOC_No,
+	MDOC_Ns,
+	MDOC_Nx,
+	MDOC_Ox,
+	MDOC_Pc,
+	MDOC_Pf,
+	MDOC_Po,
+	MDOC_Pq,
+	MDOC_Qc,
+	MDOC_Ql,
+	MDOC_Qo,
+	MDOC_Qq,
+	MDOC_Re,
+	MDOC_Rs,
+	MDOC_Sc,
+	MDOC_So,
+	MDOC_Sq,
+	MDOC_Sm,
+	MDOC_Sx,
+	MDOC_Sy,
+	MDOC_Tn,
+	MDOC_Ux,
+	MDOC_Xc,
+	MDOC_Xo,
+	MDOC_Fo,
+	MDOC_Fc,
+	MDOC_Oo,
+	MDOC_Oc,
+	MDOC_Bk,
+	MDOC_Ek,
+	MDOC_Bt,
+	MDOC_Hf,
+	MDOC_Fr,
+	MDOC_Ud,
+	MDOC_Lb,
+	MDOC_Lp,
+	MDOC_Lk,
+	MDOC_Mt,
+	MDOC_Brq,
+	MDOC_Bro,
+	MDOC_Brc,
+	MDOC__C,
+	MDOC_Es,
+	MDOC_En,
+	MDOC_Dx,
+	MDOC__Q,
+	MDOC_br,
+	MDOC_sp,
+	MDOC__U,
+	MDOC_Ta,
+	MDOC_MAX
+};
+
+/* 
+ * What follows is a list of ALL possible macro arguments. 
+ */
+enum	mdocargt {
+	MDOC_Split,
+	MDOC_Nosplit,
+	MDOC_Ragged,
+	MDOC_Unfilled,
+	MDOC_Literal,
+	MDOC_File,
+	MDOC_Offset,
+	MDOC_Bullet,
+	MDOC_Dash,
+	MDOC_Hyphen,
+	MDOC_Item,
+	MDOC_Enum,
+	MDOC_Tag,
+	MDOC_Diag,
+	MDOC_Hang,
+	MDOC_Ohang,
+	MDOC_Inset,
+	MDOC_Column,
+	MDOC_Width,
+	MDOC_Compact,
+	MDOC_Std,
+	MDOC_Filled,
+	MDOC_Words,
+	MDOC_Emphasis,
+	MDOC_Symbolic,
+	MDOC_Nested,
+	MDOC_Centred,
+	MDOC_ARG_MAX
+};
+
+/* 
+ * Type of a syntax node. 
+ */
+enum	mdoc_type {
+	MDOC_TEXT,
+	MDOC_ELEM,
+	MDOC_HEAD,
+	MDOC_TAIL,
+	MDOC_BODY,
+	MDOC_BLOCK,
+	MDOC_ROOT
+};
+
+/* 
+ * Section (named/unnamed) of `Sh'.   Note that these appear in the
+ * conventional order imposed by mdoc.7.
+ */
+enum	mdoc_sec {
+	SEC_NONE = 0, /* No section, yet. */
+	SEC_NAME,
+	SEC_LIBRARY,
+	SEC_SYNOPSIS,
+	SEC_DESCRIPTION,
+	SEC_IMPLEMENTATION,
+	SEC_RETURN_VALUES,
+	SEC_ENVIRONMENT, 
+	SEC_FILES,
+	SEC_EXIT_STATUS,
+	SEC_EXAMPLES,
+	SEC_DIAGNOSTICS,
+	SEC_COMPATIBILITY,
+	SEC_ERRORS,
+	SEC_SEE_ALSO,
+	SEC_STANDARDS,
+	SEC_HISTORY,
+	SEC_AUTHORS,
+	SEC_CAVEATS,
+	SEC_BUGS,
+	SEC_SECURITY,
+	SEC_CUSTOM, /* User-defined. */
+	SEC__MAX
+};
+
+/* 
+ * Information from prologue. 
+ */
+struct	mdoc_meta {
+	char		 *msec; /* `Dt' section (1, 3p, etc.) */
+	char		 *vol; /* `Dt' volume (implied) */
+	char		 *arch; /* `Dt' arch (i386, etc.) */
+	time_t		  date; /* `Dd' normalised date */
+	char		 *title; /* `Dt' title (FOO, etc.) */
+	char		 *os; /* `Os' system (OpenBSD, etc.) */
+	char		 *name; /* leading `Nm' name */
+};
+
+/* 
+ * An argument to a macro (multiple values = `-column xxx yyy'). 
+ */
+struct	mdoc_argv {
+	enum mdocargt  	  arg; /* type of argument */
+	int		  line;
+	int		  pos;
+	size_t		  sz; /* elements in "value" */
+	char		**value; /* argument strings */
+};
+
 /*
- * This library implements a validating scanner/parser for ``mdoc'' roff
- * macro documents, a.k.a. BSD manual page documents.  The mdoc.c file
- * drives the parser, while macro.c describes the macro ontologies.
- * validate.c pre- and post-validates parsed macros, and action.c
- * performs actions on parsed and validated macros.
+ * Reference-counted macro arguments.  These are refcounted because
+ * blocks have multiple instances of the same arguments spread across
+ * the HEAD, BODY, TAIL, and BLOCK node types.
  */
+struct 	mdoc_arg {
+	size_t		  argc;
+	struct mdoc_argv *argv;
+	unsigned int	  refcnt;
+};
 
-/* See mdoc.3 for documentation. */
+/*
+ * Indicates that a BODY's formatting has ended, but the scope is still
+ * open.  Used for syntax-broken blocks.
+ */
+enum	mdoc_endbody {
+	ENDBODY_NOT = 0,
+	ENDBODY_SPACE, /* is broken: append a space */
+	ENDBODY_NOSPACE /* is broken: don't append a space */
+};
+
+/*
+ * Normalised `Bl' list type.
+ */
+enum	mdoc_list {
+	LIST__NONE = 0,
+	LIST_bullet,
+	LIST_column,
+	LIST_dash,
+	LIST_diag,
+	LIST_enum,
+	LIST_hang,
+	LIST_hyphen,
+	LIST_inset,
+	LIST_item,
+	LIST_ohang,
+	LIST_tag
+};
+
+/*
+ * Normalised `Bd' display type.
+ */
+enum	mdoc_disp {
+	DISP__NONE = 0,
+	DISP_centred,
+	DISP_ragged,
+	DISP_unfilled,
+	DISP_filled,
+	DISP_literal
+};
+
+/*
+ * Normalised `An' splitting argument. 
+ */
+enum	mdoc_auth {
+	AUTH__NONE = 0,
+	AUTH_split,
+	AUTH_nosplit
+};
 
+/*
+ * Normalised `Bf' font type.
+ */
+enum	mdoc_font {
+	FONT__NONE = 0,
+	FONT_Em,
+	FONT_Li,
+	FONT_Sy
+};
+
+/*
+ * Normalised arguments for `Bd'.
+ */
+struct	mdoc_bd {
+	const char	 *offs; /* -offset */
+	enum mdoc_disp	  type; /* -ragged, etc. */
+	int		  comp; /* -compact */
+};
+
+/*
+ * Normalised arguments for `Bl'.
+ */
+struct	mdoc_bl {
+	const char	 *width; /* -width */
+	const char	 *offs; /* -offset */
+	enum mdoc_list	  type; /* -tag, -enum, etc. */
+	int		  comp; /* -compact */
+	size_t		  ncols; /* -column arg count */
+	const char	**cols; /* -column val ptr */
+};
+
+/*
+ * Normalised arguments for `Bf'.
+ */
+struct	mdoc_bf {
+	enum mdoc_font	  font; /* font */
+};
+
+/*
+ * Normalised arguments for `An'.
+ */
+struct	mdoc_an {
+	enum mdoc_auth	  auth; /* -split, etc. */
+};
+
+/*
+ * Consists of normalised node arguments.  These should be used instead
+ * of iterating through the mdoc_arg pointers of a node: defaults are
+ * provided, etc.
+ */
+union mdoc_data {
+	struct mdoc_an 	  An;
+	struct mdoc_bd	 *Bd;
+	struct mdoc_bf	 *Bf;
+	struct mdoc_bl	 *Bl;
+};
+
+/* 
+ * Single node in tree-linked AST. 
+ */
+struct	mdoc_node {
+	struct mdoc_node *parent; /* parent AST node */
+	struct mdoc_node *child; /* first child AST node */
+	struct mdoc_node *next; /* sibling AST node */
+	struct mdoc_node *prev; /* prior sibling AST node */
+	int		  nchild; /* number children */
+	int		  line; /* parse line */
+	int		  pos; /* parse column */
+	enum mdoct	  tok; /* tok or MDOC__MAX if none */
+	int		  flags;
+#define	MDOC_VALID	 (1 << 0) /* has been validated */
+#define	MDOC_ACTED	 (1 << 1) /* has been acted upon */
+#define	MDOC_EOS	 (1 << 2) /* at sentence boundary */
+#define	MDOC_LINE	 (1 << 3) /* first macro/text on line */
+#define	MDOC_SYNPRETTY	 (1 << 4) /* SYNOPSIS-style formatting */
+#define	MDOC_ENDED	 (1 << 5) /* rendering has been ended */
+	enum mdoc_type	  type; /* AST node type */
+	enum mdoc_sec	  sec; /* current named section */
+	/* FIXME: these can be union'd to shave a few bytes. */
+	struct mdoc_arg	 *args; /* BLOCK/ELEM */
+	struct mdoc_node *pending; /* BLOCK */
+	struct mdoc_node *head; /* BLOCK */
+	struct mdoc_node *body; /* BLOCK */
+	struct mdoc_node *tail; /* BLOCK */
+	char		 *string; /* TEXT */
+	enum mdoc_endbody end; /* BODY */
+	union mdoc_data	  data;
+};
+
+/*
+ * Names of macros.  Index is enum mdoct.  Indexing into this returns
+ * the normalised name, e.g., mdoc_macronames[MDOC_Sh] -> "Sh".
+ */
 extern	const char *const *mdoc_macronames;
+
+/*
+ * Names of macro args.  Index is enum mdocargt.  Indexing into this
+ * returns the normalised name, e.g., mdoc_argnames[MDOC_File] ->
+ * "file".
+ */
 extern	const char *const *mdoc_argnames;
 
 __BEGIN_DECLS
 
 struct	mdoc;
 
-/* See mdoc.3 for documentation. */
-
 void	 	  mdoc_free(struct mdoc *);
 struct	mdoc	 *mdoc_alloc(struct regset *, void *, mandocmsg);
 void		  mdoc_reset(struct mdoc *);