[mirror_frr.git] / lib / defun_lex.l

/*
 * clippy (CLI preparator in python) C pseudo-lexer
 * Copyright (C) 2016-2017  David Lamparter for NetDEF, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

/* This is just enough of a lexer to make rough sense of a C source file.
 * It handles C preprocessor directives, strings, and looks for FRR-specific
 * idioms (aka DEFUN).
 *
 * There is some preliminary support for documentation comments for DEFUNs.
 * They would look like this (note the ~):  (replace \ by /)
 *
 * \*~  documentation for foobar_cmd
 *  *   parameter does xyz
 *  *\
 * DEFUN(foobar_cmd, ...)
 *
 * This is intended for user documentation / command reference.  Don't put
 * code documentation in it.
 */

%top{
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
}
%{
/* ignore harmless bugs in old versions of flex */
#pragma GCC diagnostic ignored "-Wsign-compare"
#pragma GCC diagnostic ignored "-Wunused-value"

#include "config.h"
#include <Python.h>
#include <string.h>
#include <stdlib.h>

#include "command_graph.h"
#include "clippy.h"

#define ID		258
#define PREPROC		259
#define OPERATOR	260
#define STRING		261
#define COMMENT		262
#define SPECIAL		263

#define DEFUNNY		270
#define INSTALL		271
#define AUXILIARY	272

int comment_link;
char string_end;

char *value;

static void extendbuf(char **what, const char *arg)
{
	if (!*what)
		*what = strdup(arg);
	else {
		size_t vall = strlen(*what), argl = strlen(arg);
		*what = realloc(*what, vall + argl + 1);
		memcpy(*what + vall, arg, argl);
		(*what)[vall + argl] = '\0';
	}
}
#define extend(x) extendbuf(&value, x)

%}

ID		[A-Za-z0-9_]+
OPERATOR	[!%&/\[\]{}=?:^|\*.;><~'\\+-]
SPECIAL		[(),]

%pointer
%option yylineno
%option noyywrap
%option noinput
%option nounput
%option outfile="lib/defun_lex.c"
%option prefix="def_yy"
%option 8bit

%s linestart
%x comment
%x linecomment
%x preproc
%x rstring
%%
				BEGIN(linestart);

\n				BEGIN(linestart);

<INITIAL,linestart,preproc>"/*"	comment_link = YY_START; extend(yytext); BEGIN(comment);
<comment>[^*\n]*		extend(yytext);
<comment>"*"+[^*/\n]*		extend(yytext);
<comment>\n			extend(yytext);
<comment>"*"+"/"		extend(yytext); BEGIN(comment_link); return COMMENT;

<INITIAL,linestart,preproc>"//"	comment_link = YY_START; extend(yytext); BEGIN(linecomment);
<linecomment>[^\n]*		extend(yytext);
<linecomment>\n			BEGIN((comment_link == INITIAL) ? linestart : comment_link); return COMMENT;

<linestart>#			BEGIN(preproc);
<preproc>\n			BEGIN(INITIAL); return PREPROC;
<preproc>[^\n\\]+		extend(yytext);
<preproc>\\\n			extend(yytext);
<preproc>\\+[^\n]		extend(yytext);

[\"\']				string_end = yytext[0]; extend(yytext); BEGIN(rstring);
<rstring>[\"\']			{
					extend(yytext);
					if (yytext[0] == string_end) {
						BEGIN(INITIAL);
						return STRING;
					}
				}
<rstring>\\\n			/* ignore */
<rstring>\\.			extend(yytext);
<rstring>[^\\\"\']+		extend(yytext);

"DEFUN"				value = strdup(yytext); return DEFUNNY;
"DEFUN_NOSH"			value = strdup(yytext); return DEFUNNY;
"DEFUN_HIDDEN"			value = strdup(yytext); return DEFUNNY;
"DEFPY"				value = strdup(yytext); return DEFUNNY;
"DEFPY_NOSH"			value = strdup(yytext); return DEFUNNY;
"DEFPY_ATTR"			value = strdup(yytext); return DEFUNNY;
"DEFPY_HIDDEN"			value = strdup(yytext); return DEFUNNY;
"ALIAS"				value = strdup(yytext); return DEFUNNY;
"ALIAS_HIDDEN"			value = strdup(yytext); return DEFUNNY;
"install_element"		value = strdup(yytext); return INSTALL;
"VTYSH_TARGETS"			value = strdup(yytext); return AUXILIARY;
"VTYSH_NODESWITCH"		value = strdup(yytext); return AUXILIARY;

[ \t\n]+			/* ignore */
\\				/* ignore */
{ID}				BEGIN(INITIAL); value = strdup(yytext); return ID;
{OPERATOR}			BEGIN(INITIAL); value = strdup(yytext); return OPERATOR;
{SPECIAL}			BEGIN(INITIAL); value = strdup(yytext); return SPECIAL;
.				/* printf("-- '%s' in init\n", yytext); */ BEGIN(INITIAL); return yytext[0];

%%

static int yylex_clr(char **retbuf)
{
	int rv = def_yylex();
	*retbuf = value;
	value = NULL;
	return rv;
}

static PyObject *get_args(const char *filename, int lineno)
{
	PyObject *pyObj = PyList_New(0);
	PyObject *pyArg = NULL;

	char *tval;
	int depth = 1;
	int token;

	while ((token = yylex_clr(&tval)) != YY_NULL) {
		if (token == SPECIAL && tval[0] == '(') {
			free(tval);
			break;
		}
		if (token == COMMENT) {
			free(tval);
			continue;
		}
		fprintf(stderr, "invalid input!\n");
		exit(1);
	}

	while ((token = yylex_clr(&tval)) != YY_NULL) {
		if (token == COMMENT) {
			free(tval);
			continue;
		}
		if (token == PREPROC) {
			free(tval);
			Py_DECREF(pyObj);
			return PyErr_Format(PyExc_ValueError,
					"%s:%d: cannot process CPP directive within argument list",
					filename, lineno);
		}
		if (token == SPECIAL) {
			if (depth == 1 && (tval[0] == ',' || tval[0] == ')')) {
				if (pyArg)
					PyList_Append(pyObj, pyArg);
				pyArg = NULL;
				if (tval[0] == ')') {
					free(tval);
					break;
				}
				free(tval);
				continue;
			}
			if (tval[0] == '(')
				depth++;
			if (tval[0] == ')')
				depth--;
		}
		if (!pyArg)
			pyArg = PyList_New(0);
		PyList_Append(pyArg, PyUnicode_FromString(tval));
		free(tval);
	}
	return pyObj;
}

/* _clippy.parse() -- read a C file, returning a list of interesting bits.
 * note this ditches most of the actual C code. */
PyObject *clippy_parse(PyObject *self, PyObject *args)
{
	const char *filename;
	if (!PyArg_ParseTuple(args, "s", &filename))
		return NULL;
	
	FILE *fd = fopen(filename, "r");
	if (!fd)
		return PyErr_SetFromErrnoWithFilename(PyExc_IOError, filename);

	char *tval;
	int token;
	yyin = fd;
	value = NULL;

	PyObject *pyCont = PyDict_New();
	PyObject *pyObj = PyList_New(0);
	PyDict_SetItemString(pyCont, "filename", PyUnicode_FromString(filename));
	PyDict_SetItemString(pyCont, "data", pyObj);

	while ((token = yylex_clr(&tval)) != YY_NULL) {
                int lineno = yylineno;
		PyObject *pyItem = NULL, *pyArgs;
		switch (token) {
		case DEFUNNY:
		case INSTALL:
		case AUXILIARY:
			pyArgs = get_args(filename, lineno);
			if (!pyArgs) {
				free(tval);
				Py_DECREF(pyCont);
				return NULL;
			}
			pyItem = PyDict_New();
			PyDict_SetItemString(pyItem, "type", PyUnicode_FromString(tval));
			PyDict_SetItemString(pyItem, "args", pyArgs);
			break;
		case COMMENT:
                        if (strncmp(tval, "//~", 3) && strncmp(tval, "/*~", 3))
                                break;
			pyItem = PyDict_New();
			PyDict_SetItemString(pyItem, "type", PyUnicode_FromString("COMMENT"));
			PyDict_SetItemString(pyItem, "line", PyUnicode_FromString(tval));
			break;
		case PREPROC:
			pyItem = PyDict_New();
			PyDict_SetItemString(pyItem, "type", PyUnicode_FromString("PREPROC"));
			PyDict_SetItemString(pyItem, "line", PyUnicode_FromString(tval));
			lineno--;
			break;
		}
		if (pyItem) {
			PyDict_SetItemString(pyItem, "lineno", PyLong_FromLong(lineno));
			PyList_Append(pyObj, pyItem);
		}
		free(tval);
	}
	def_yylex_destroy();
	fclose(fd);
	return pyCont;
}
Commit	Line	Data
29ad6f68 DL	1	/*
	2	* clippy (CLI preparator in python) C pseudo-lexer
	3	* Copyright (C) 2016-2017 David Lamparter for NetDEF, Inc.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; either version 2 of the License, or (at your option)
	8	* any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	* You should have received a copy of the GNU General Public License along
	16	* with this program; see the file COPYING; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	18	*/
	19
	20	/* This is just enough of a lexer to make rough sense of a C source file.
	21	* It handles C preprocessor directives, strings, and looks for FRR-specific
	22	* idioms (aka DEFUN).
	23	*
	24	* There is some preliminary support for documentation comments for DEFUNs.
	25	* They would look like this (note the ~): (replace \ by /)
	26	*
	27	* \*~ documentation for foobar_cmd
	28	* * parameter does xyz
	29	* *\
	30	* DEFUN(foobar_cmd, ...)
	31	*
	32	* This is intended for user documentation / command reference. Don't put
	33	* code documentation in it.
	34	*/
	35
7b34167d DL	36	%top{
	37	#ifdef HAVE_CONFIG_H
	38	#include "config.h"
	39	#endif
	40	}
	41	%{
a37bd5e0	42	/* ignore harmless bugs in old versions of flex */
29ad6f68	43	#pragma GCC diagnostic ignored "-Wsign-compare"
a37bd5e0	44	#pragma GCC diagnostic ignored "-Wunused-value"
29ad6f68 DL	45
	46	#include "config.h"
	47	#include <Python.h>
	48	#include <string.h>
	49	#include <stdlib.h>
	50
	51	#include "command_graph.h"
	52	#include "clippy.h"
	53
	54	#define ID 258
	55	#define PREPROC 259
	56	#define OPERATOR 260
	57	#define STRING 261
	58	#define COMMENT 262
	59	#define SPECIAL 263
	60
	61	#define DEFUNNY 270
	62	#define INSTALL 271
	63	#define AUXILIARY 272
	64
	65	int comment_link;
	66	char string_end;
	67
	68	char *value;
	69
	70	static void extendbuf(char *what, const char arg)
	71	{
	72	if (!*what)
	73	*what = strdup(arg);
	74	else {
	75	size_t vall = strlen(*what), argl = strlen(arg);
	76	what = realloc(what, vall + argl + 1);
	77	memcpy(*what + vall, arg, argl);
	78	(*what)[vall + argl] = '\0';
	79	}
	80	}
	81	#define extend(x) extendbuf(&value, x)
	82
	83	%}
	84
	85	ID [A-Za-z0-9_]+
	86	OPERATOR [!%&/\[\]{}=?:^\|\*.;><~'\\+-]
	87	SPECIAL [(),]
	88
	89	%pointer
	90	%option yylineno
	91	%option noyywrap
	92	%option noinput
	93	%option nounput
4a121f99	94	%option outfile="lib/defun_lex.c"
29ad6f68 DL	95	%option prefix="def_yy"
	96	%option 8bit
	97
	98	%s linestart
	99	%x comment
	100	%x linecomment
	101	%x preproc
	102	%x rstring
	103	%%
	104	BEGIN(linestart);
	105
	106	\n BEGIN(linestart);
	107
	108	<INITIAL,linestart,preproc>"/*" comment_link = YY_START; extend(yytext); BEGIN(comment);
	109	<comment>[^\n] extend(yytext);
	110	<comment>""+[^/\n]* extend(yytext);
	111	<comment>\n extend(yytext);
	112	<comment>"*"+"/" extend(yytext); BEGIN(comment_link); return COMMENT;
	113
	114	<INITIAL,linestart,preproc>"//" comment_link = YY_START; extend(yytext); BEGIN(linecomment);
	115	<linecomment>[^\n]* extend(yytext);
	116	<linecomment>\n BEGIN((comment_link == INITIAL) ? linestart : comment_link); return COMMENT;
	117
	118	<linestart># BEGIN(preproc);
	119	<preproc>\n BEGIN(INITIAL); return PREPROC;
	120	<preproc>[^\n\\]+ extend(yytext);
	121	<preproc>\\\n extend(yytext);
	122	<preproc>\\+[^\n] extend(yytext);
	123
	124	[\"\'] string_end = yytext[0]; extend(yytext); BEGIN(rstring);
	125	<rstring>[\"\'] {
	126	extend(yytext);
	127	if (yytext[0] == string_end) {
	128	BEGIN(INITIAL);
	129	return STRING;
	130	}
	131	}
	132	<rstring>\\\n /* ignore */
	133	<rstring>\\. extend(yytext);
	134	<rstring>[^\\\"\']+ extend(yytext);
	135
	136	"DEFUN" value = strdup(yytext); return DEFUNNY;
	137	"DEFUN_NOSH" value = strdup(yytext); return DEFUNNY;
	138	"DEFUN_HIDDEN" value = strdup(yytext); return DEFUNNY;
	139	"DEFPY" value = strdup(yytext); return DEFUNNY;
26d19c83	140	"DEFPY_NOSH" value = strdup(yytext); return DEFUNNY;
e31f4dbe QY	141	"DEFPY_ATTR" value = strdup(yytext); return DEFUNNY;
e31f4dbe QY	142	"DEFPY_HIDDEN" value = strdup(yytext); return DEFUNNY;
29ad6f68 DL	143	"ALIAS" value = strdup(yytext); return DEFUNNY;
	144	"ALIAS_HIDDEN" value = strdup(yytext); return DEFUNNY;
	145	"install_element" value = strdup(yytext); return INSTALL;
	146	"VTYSH_TARGETS" value = strdup(yytext); return AUXILIARY;
	147	"VTYSH_NODESWITCH" value = strdup(yytext); return AUXILIARY;
	148
	149	[ \t\n]+ /* ignore */
	150	\\ /* ignore */
	151	{ID} BEGIN(INITIAL); value = strdup(yytext); return ID;
	152	{OPERATOR} BEGIN(INITIAL); value = strdup(yytext); return OPERATOR;
	153	{SPECIAL} BEGIN(INITIAL); value = strdup(yytext); return SPECIAL;
	154	. /* printf("-- '%s' in init\n", yytext); */ BEGIN(INITIAL); return yytext[0];
	155
	156	%%
	157
	158	static int yylex_clr(char **retbuf)
	159	{
	160	int rv = def_yylex();
	161	*retbuf = value;
	162	value = NULL;
	163	return rv;
	164	}
	165
3779776a	166	static PyObject get_args(const char filename, int lineno)
29ad6f68 DL	167	{
	168	PyObject *pyObj = PyList_New(0);
	169	PyObject *pyArg = NULL;
	170
	171	char *tval;
	172	int depth = 1;
	173	int token;
	174
	175	while ((token = yylex_clr(&tval)) != YY_NULL) {
	176	if (token == SPECIAL && tval[0] == '(') {
	177	free(tval);
	178	break;
	179	}
	180	if (token == COMMENT) {
	181	free(tval);
	182	continue;
	183	}
	184	fprintf(stderr, "invalid input!\n");
	185	exit(1);
	186	}
	187
	188	while ((token = yylex_clr(&tval)) != YY_NULL) {
	189	if (token == COMMENT) {
	190	free(tval);
	191	continue;
	192	}
3779776a DL	193	if (token == PREPROC) {
	194	free(tval);
	195	Py_DECREF(pyObj);
	196	return PyErr_Format(PyExc_ValueError,
	197	"%s:%d: cannot process CPP directive within argument list",
	198	filename, lineno);
	199	}
29ad6f68 DL	200	if (token == SPECIAL) {
	201	if (depth == 1 && (tval[0] == ',' \|\| tval[0] == ')')) {
	202	if (pyArg)
	203	PyList_Append(pyObj, pyArg);
	204	pyArg = NULL;
	205	if (tval[0] == ')') {
	206	free(tval);
	207	break;
	208	}
	209	free(tval);
	210	continue;
	211	}
	212	if (tval[0] == '(')
	213	depth++;
	214	if (tval[0] == ')')
	215	depth--;
	216	}
	217	if (!pyArg)
	218	pyArg = PyList_New(0);
	219	PyList_Append(pyArg, PyUnicode_FromString(tval));
	220	free(tval);
	221	}
	222	return pyObj;
	223	}
	224
	225	/* _clippy.parse() -- read a C file, returning a list of interesting bits.
	226	* note this ditches most of the actual C code. */
	227	PyObject clippy_parse(PyObject self, PyObject *args)
	228	{
	229	const char *filename;
	230	if (!PyArg_ParseTuple(args, "s", &filename))
	231	return NULL;
	232
	233	FILE *fd = fopen(filename, "r");
	234	if (!fd)
	235	return PyErr_SetFromErrnoWithFilename(PyExc_IOError, filename);
	236
	237	char *tval;
	238	int token;
	239	yyin = fd;
	240	value = NULL;
	241
	242	PyObject *pyCont = PyDict_New();
	243	PyObject *pyObj = PyList_New(0);
	244	PyDict_SetItemString(pyCont, "filename", PyUnicode_FromString(filename));
	245	PyDict_SetItemString(pyCont, "data", pyObj);
	246
	247	while ((token = yylex_clr(&tval)) != YY_NULL) {
	248	int lineno = yylineno;
	249	PyObject pyItem = NULL, pyArgs;
	250	switch (token) {
	251	case DEFUNNY:
	252	case INSTALL:
	253	case AUXILIARY:
3779776a DL	254	pyArgs = get_args(filename, lineno);
	255	if (!pyArgs) {
	256	free(tval);
	257	Py_DECREF(pyCont);
	258	return NULL;
	259	}
29ad6f68 DL	260	pyItem = PyDict_New();
	261	PyDict_SetItemString(pyItem, "type", PyUnicode_FromString(tval));
	262	PyDict_SetItemString(pyItem, "args", pyArgs);
	263	break;
	264	case COMMENT:
	265	if (strncmp(tval, "//~", 3) && strncmp(tval, "/*~", 3))
	266	break;
	267	pyItem = PyDict_New();
	268	PyDict_SetItemString(pyItem, "type", PyUnicode_FromString("COMMENT"));
	269	PyDict_SetItemString(pyItem, "line", PyUnicode_FromString(tval));
	270	break;
	271	case PREPROC:
	272	pyItem = PyDict_New();
	273	PyDict_SetItemString(pyItem, "type", PyUnicode_FromString("PREPROC"));
	274	PyDict_SetItemString(pyItem, "line", PyUnicode_FromString(tval));
3779776a	275	lineno--;
29ad6f68 DL	276	break;
	277	}
	278	if (pyItem) {
	279	PyDict_SetItemString(pyItem, "lineno", PyLong_FromLong(lineno));
	280	PyList_Append(pyObj, pyItem);
	281	}
	282	free(tval);
	283	}
	284	def_yylex_destroy();
	285	fclose(fd);
	286	return pyCont;
	287	}