Segmentation into html and dummy parsers.

Initial recursive-descent parser in place for html/ml parser.
Parsing of title tags more-or-less in place.

1 files changed, 451 insertions, 0 deletions

diff --git a/html4_strict.c b/html4_strict.c
new file mode 100644
index 00000000..6da9fd51
--- /dev/null
+++ b/html4_strict.c
@@ -0,0 +1,451 @@
+/* $Id$ */
+/*
+ * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the
+ * above copyright notice and this permission notice appear in all
+ * copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+#include <assert.h>
+#include <ctype.h>
+#include <err.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+#include "libmdocml.h"
+#include "private.h"
+
+enum	roffd {
+	ROFF_ENTER = 0,
+	ROFF_EXIT
+};
+
+enum	rofftype {
+	ROFF_NONE = 0,
+	ROFF_LAYOUT
+};
+
+struct rofftree;
+
+#define	ROFFCALL_ARGS	  const struct md_args *arg,		\
+			  struct md_mbuf *out,			\
+			  const struct md_rbuf *in,		\
+			  const char *buf, size_t sz,		\
+			  size_t pos, enum roffd type,		\
+			  struct rofftree *tree
+typedef	int		(*roffcall)(ROFFCALL_ARGS);
+
+static	int		  roff_Dd(ROFFCALL_ARGS);
+static	int		  roff_Dt(ROFFCALL_ARGS);
+static	int		  roff_Os(ROFFCALL_ARGS);
+static	int		  roff_Sh(ROFFCALL_ARGS);
+
+struct	rofftok {
+	char		  id;
+#define	ROFF___	 	  0
+#define	ROFF_Dd		  1
+#define	ROFF_Dt		  2
+#define	ROFF_Os		  3
+#define	ROFF_Sh		  4
+#define	ROFF_Max	  5
+	char		  name[2];
+	roffcall	  cb;
+	enum rofftype	  type;
+	int		  flags;
+#define	ROFF_NESTED	 (1 << 0)
+};
+
+static const struct rofftok tokens[ROFF_Max] = {
+	{ ROFF___,    "\\\"",	   NULL, ROFF_NONE,	0 },
+	{ ROFF_Dd,	"Dd",	roff_Dd, ROFF_NONE,	0 },
+	{ ROFF_Dt,	"Dt",	roff_Dt, ROFF_NONE,	0 },
+	{ ROFF_Os,	"Os",	roff_Os, ROFF_LAYOUT,	0 },
+	{ ROFF_Sh,	"Sh",	roff_Sh, ROFF_LAYOUT,	0 },
+};
+
+struct	roffnode {
+	int		  tok;	
+	struct roffnode	 *parent;
+	/* TODO: line number at acquisition. */
+};
+
+struct rofftree {
+	struct roffnode	 *last;
+
+	time_t		  date;
+	char		  title[256];
+	char		  section[256];
+	char		  volume[256];
+
+	int		  state;
+#define	ROFF_PRELUDE	 (1 << 0)
+#define	ROFF_PRELUDE_Os	 (1 << 1)
+#define	ROFF_PRELUDE_Dt	 (1 << 2)
+#define	ROFF_PRELUDE_Dd	 (1 << 3)
+};
+
+static int		  rofffind(const char *);
+static int 		  roffparse(const struct md_args *, 
+				struct md_mbuf *,
+				const struct md_rbuf *, 
+				const char *, size_t,
+				struct rofftree *);
+static int		  textparse(struct md_mbuf *, 
+				const struct md_rbuf *, 
+				const char *, size_t, 
+				const struct rofftree *);
+
+
+int
+md_exit_html4_strict(const struct md_args *args, struct md_mbuf *out, 
+		const struct md_rbuf *in, void *data)
+{
+	struct rofftree	*tree;
+	int		 error;
+
+	assert(args);
+	assert(data);
+	tree = (struct rofftree *)data;
+	error = 0;
+
+	while (tree->last)
+		if ( ! (*tokens[tree->last->tok].cb)
+				(args, error ? NULL : out, in, NULL,
+				 0, 0, ROFF_EXIT, tree))
+			error = 1;
+
+	free(tree);
+	return(error ? 0 : 1);
+}
+
+
+int
+md_init_html4_strict(const struct md_args *args, struct md_mbuf *out, 
+		const struct md_rbuf *in, void **data) 
+{
+	struct rofftree	*tree;
+
+	assert(args);
+	assert(in);
+	assert(out);
+	assert(data);
+
+	/* TODO: write HTML-DTD header. */
+
+	if (NULL == (tree = calloc(1, sizeof(struct rofftree)))) {
+		warn("malloc");
+		return(0);
+	}
+
+	*data = tree;
+	return(1);
+}
+
+
+int
+md_line_html4_strict(const struct md_args *args, struct md_mbuf *out, 
+		const struct md_rbuf *in, const char *buf, 
+		size_t sz, void *data)
+{
+	struct rofftree	*tree;
+
+	assert(args);
+	assert(in);
+	assert(data);
+
+	tree = (struct rofftree *)data;
+
+	if (0 == sz) {
+		warnx("%s: blank line (line %zu)", in->name, in->line);
+		return(0);
+	} else if ('.' != *buf)
+		return(textparse(out, in, buf, sz, tree));
+
+	return(roffparse(args, out, in, buf, sz, tree));
+}
+
+
+static int
+textparse(struct md_mbuf *out, const struct md_rbuf *in, 
+		const char *buf, size_t sz, 
+		const struct rofftree *tree)
+{
+	
+	assert(tree);
+	assert(out);
+	assert(in);
+	assert(buf);
+	assert(sz > 0);
+
+	if (NULL == tree->last) {
+		warnx("%s: unexpected text (line %zu)",
+				in->name, in->line);
+		return(0);
+	} else if (NULL == tree->last->parent) {
+		warnx("%s: disallowed text (line %zu)",
+				in->name, in->line);
+		return(0);
+	}
+
+	if ( ! md_buf_puts(out, buf, sz))
+		return(0);
+	return(md_buf_putstring(out, " "));
+}
+
+
+static int
+roffparse(const struct md_args *args, struct md_mbuf *out,
+		const struct md_rbuf *in, const char *buf,
+		size_t sz, struct rofftree *tree)
+{
+	int		 tokid, t;
+	size_t		 pos;
+	struct roffnode	*node;
+
+	assert(args);
+	assert(out);
+	assert(in);
+	assert(buf);
+	assert(sz > 0);
+	assert(tree);
+
+	/*
+	 * Extract the token identifier from the buffer.  If there's no
+	 * callback for the token (comment, etc.) then exit immediately.
+	 * We don't do any error handling (yet), so if the token doesn't
+	 * exist, die.
+	 */
+
+	if (3 > sz) {
+		warnx("%s: malformed input (line %zu, col 1)", 
+				in->name, in->line);
+		return(0);
+	} else if (ROFF_Max == (tokid = rofffind(buf + 1))) {
+		warnx("%s: unknown token `%c%c' (line %zu, col 1)",
+				in->name, *(buf + 1), 
+				*(buf + 2), in->line);
+		return(0);
+	} else if (NULL == tokens[tokid].cb) 
+		return(1); /* Skip token. */
+
+	pos = 3;
+
+	/*
+	 * If this is a non-nestable layout token and we're below a
+	 * token of the same type, then recurse upward to the token,
+	 * closing out the interim scopes.
+	 *
+	 * If there's a nested token on the chain, then raise an error
+	 * as nested tokens have corresponding "ending" tokens and we're
+	 * breaking their scope.
+	 */
+
+	node = NULL;
+
+	if (ROFF_LAYOUT == tokens[tokid].type && 
+			! (ROFF_NESTED & tokens[tokid].flags)) {
+		for (node = tree->last; node; node = node->parent) {
+			if (node->tok == tokid)
+				break;
+
+			/* Don't break nested scope. */
+
+			if ( ! (ROFF_NESTED & tokens[node->tok].flags))
+				continue;
+			warnx("%s: scope of %s broken by %s "
+					"(line %zu, col %zu)",
+					in->name, tokens[tokid].name,
+					tokens[node->tok].name,
+					in->line, pos);
+			return(0);
+		}
+	}
+	if (node) {
+		assert(ROFF_LAYOUT == tokens[tokid].type);
+		assert( ! (ROFF_NESTED & tokens[tokid].flags));
+		assert(node->tok == tokid);
+
+		/* Clear up to last scoped token. */
+
+		do {
+			t = tree->last->tok;
+			if ( ! (*tokens[tree->last->tok].cb)
+					(args, out, in, NULL,
+					 0, 0, ROFF_EXIT, tree))
+				return(0);
+		} while (t != tokid);
+	}
+
+	/* Proceed with actual token processing. */
+
+	return((*tokens[tokid].cb)(args, out, in, buf, sz, 
+				pos, ROFF_ENTER, tree));
+}
+
+
+static int
+rofffind(const char *name)
+{
+	size_t		 i;
+
+	assert(name);
+	/* FIXME: use a table, this is slow but ok for now. */
+	for (i = 0; i < ROFF_Max; i++)
+		if (0 == strncmp(name, tokens[i].name, 2))
+			return(i);
+	
+	return(ROFF_Max);
+}
+
+
+/* ARGUSED */
+static	int
+roff_Dd(ROFFCALL_ARGS)
+{
+
+	assert(in);
+	assert(tree);
+	assert(arg);
+	assert(out);
+	assert(buf);
+	assert(sz > 0);
+	assert(pos > 0);
+	assert(type == ROFF_ENTER);
+
+	if (tree->last) {
+		warnx("%s: superfluous prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(0);
+	}
+
+	if (0 != tree->state) {
+		warnx("%s: bad manual prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(1);
+	}
+
+	/* TODO: parse date from buffer. */
+
+	tree->date = time(NULL);
+	tree->state |= ROFF_PRELUDE_Dd;
+	return(1);
+}
+
+
+static	int
+roff_Dt(ROFFCALL_ARGS)
+{
+
+	assert(in);
+	assert(tree);
+	assert(arg);
+	assert(out);
+	assert(buf);
+	assert(sz > 0);
+	assert(pos > 0);
+	assert(type == ROFF_ENTER);
+
+	if (tree->last) {
+		warnx("%s: superfluous prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(0);
+	}
+
+	if ( ! (ROFF_PRELUDE_Dd & tree->state) ||
+			(ROFF_PRELUDE_Os & tree->state) ||
+			(ROFF_PRELUDE_Dt & tree->state)) {
+		warnx("%s: bad manual prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(1);
+	}
+
+	/* TODO: parse titles from buffer. */
+
+	tree->state |= ROFF_PRELUDE_Dt;
+	return(1);
+}
+
+
+static	int
+roff_Os(ROFFCALL_ARGS)
+{
+	struct roffnode	*node;
+
+	assert(arg);
+	assert(tree);
+	assert(in);
+
+	if (ROFF_EXIT == type) {
+		assert(tree->last);
+		assert(tree->last->tok == ROFF_Os);
+
+		/* TODO: flush out ML footer. */
+
+		node = tree->last;
+		tree->last = node->parent;
+		free(node);
+
+		return(1);
+	} 
+
+	assert(out);
+	assert(buf);
+	assert(sz > 0);
+	assert(pos > 0);
+
+	if (tree->last) {
+		warnx("%s: superfluous prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(0);
+	}
+
+	if ((ROFF_PRELUDE_Os & tree->state) ||
+			! (ROFF_PRELUDE_Dt & tree->state) ||
+			! (ROFF_PRELUDE_Dd & tree->state)) {
+		warnx("%s: bad manual prelude (line %zu, col %zu)",
+				in->name, in->line, pos);
+		return(1);
+	}
+
+	node = malloc(sizeof(struct roffnode));
+	if (NULL == node) {
+		warn("malloc");
+		return(0);
+	}
+	node->tok = ROFF_Os;
+	node->parent = NULL;
+
+	tree->state |= ROFF_PRELUDE_Os;
+	tree->last = node;
+
+	return(1);
+}
+
+
+static	int
+roff_Sh(ROFFCALL_ARGS)
+{
+
+	assert(arg);
+	/*assert(out);*/(void)out;
+	assert(in);
+	/*assert(buf);*/(void)buf;
+	(void)sz;
+	(void)pos;
+	(void)type;
+	assert(tree);
+	return(1);
+}
+