[apple/libc.git] / util / fparseln.c

/*
 * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*	$NetBSD: fparseln.c,v 1.9 1999/09/20 04:48:06 lukem Exp $	*/

/*
 * Copyright (c) 1997 Christos Zoulas.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Christos Zoulas.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libutil/fparseln.c,v 1.5 2002/03/21 23:52:49 obrien Exp $");

#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <util.h>

static int isescaped(const char *, const char *, int);

/* isescaped():
 *	Return true if the character in *p that belongs to a string
 *	that starts in *sp, is escaped by the escape character esc.
 */
static int
isescaped(sp, p, esc)
	const char *sp, *p;
	int esc;
{
	const char     *cp;
	size_t		ne;

#if 0
	_DIAGASSERT(sp != NULL);
	_DIAGASSERT(p != NULL);
#endif

	/* No escape character */
	if (esc == '\0')
		return 1;

	/* Count the number of escape characters that precede ours */
	for (ne = 0, cp = p; --cp >= sp && *cp == esc; ne++)
		continue;

	/* Return true if odd number of escape characters */
	return (ne & 1) != 0;
}


/* fparseln():
 *	Read a line from a file parsing continuations ending in \
 *	and eliminating trailing newlines, or comments starting with
 *	the comment char.
 */
char *
fparseln(fp, size, lineno, str, flags)
	FILE		*fp;
	size_t		*size;
	size_t		*lineno;
	const char	 str[3];
	int		 flags;
{
	static const char dstr[3] = { '\\', '\\', '#' };

	size_t	s, len;
	char   *buf;
	char   *ptr, *cp;
	int	cnt;
	char	esc, con, nl, com;

#if 0
	_DIAGASSERT(fp != NULL);
#endif

	len = 0;
	buf = NULL;
	cnt = 1;

	if (str == NULL)
		str = dstr;

	esc = str[0];
	con = str[1];
	com = str[2];
	/*
	 * XXX: it would be cool to be able to specify the newline character,
	 * but unfortunately, fgetln does not let us
	 */
	nl  = '\n';

	while (cnt) {
		cnt = 0;

		if (lineno)
			(*lineno)++;

		if ((ptr = fgetln(fp, &s)) == NULL)
			break;

		if (s && com) {		/* Check and eliminate comments */
			for (cp = ptr; cp < ptr + s; cp++)
				if (*cp == com && !isescaped(ptr, cp, esc)) {
					s = cp - ptr;
					cnt = s == 0 && buf == NULL;
					break;
				}
		}

		if (s && nl) { 		/* Check and eliminate newlines */
			cp = &ptr[s - 1];

			if (*cp == nl)
				s--;	/* forget newline */
		}

		if (s && con) {		/* Check and eliminate continuations */
			cp = &ptr[s - 1];

			if (*cp == con && !isescaped(ptr, cp, esc)) {
				s--;	/* forget escape */
				cnt = 1;
			}
		}

		if (s == 0 && buf != NULL)
			continue;

		if ((cp = realloc(buf, len + s + 1)) == NULL) {
			free(buf);
			return NULL;
		}
		buf = cp;

		(void) memcpy(buf + len, ptr, s);
		len += s;
		buf[len] = '\0';
	}

	if ((flags & FPARSELN_UNESCALL) != 0 && esc && buf != NULL &&
	    strchr(buf, esc) != NULL) {
		ptr = cp = buf;
		while (cp[0] != '\0') {
			int skipesc;

			while (cp[0] != '\0' && cp[0] != esc)
				*ptr++ = *cp++;
			if (cp[0] == '\0' || cp[1] == '\0')
				break;

			skipesc = 0;
			if (cp[1] == com)
				skipesc += (flags & FPARSELN_UNESCCOMM);
			if (cp[1] == con)
				skipesc += (flags & FPARSELN_UNESCCONT);
			if (cp[1] == esc)
				skipesc += (flags & FPARSELN_UNESCESC);
			if (cp[1] != com && cp[1] != con && cp[1] != esc)
				skipesc = (flags & FPARSELN_UNESCREST);

			if (skipesc)
				cp++;
			else
				*ptr++ = *cp++;
			*ptr++ = *cp++;
		}
		*ptr = '\0';
		len = strlen(buf);
	}

	if (size)
		*size = len;
	return buf;
}

#ifdef TEST

int main(int, char **);

int
main(argc, argv)
	int argc;
	char **argv;
{
	char   *ptr;
	size_t	size, line;

	line = 0;
	while ((ptr = fparseln(stdin, &size, &line, NULL,
	    FPARSELN_UNESCALL)) != NULL)
		printf("line %d (%d) |%s|\n", line, size, ptr);
	return 0;
}

/*

# This is a test
line 1
line 2 \
line 3 # Comment
line 4 \# Not comment \\\\

# And a comment \
line 5 \\\
line 6

*/

#endif /* TEST */
Commit	Line	Data
9385eb3d A	1	/*
	2	* Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
9385eb3d A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
	12	*
	13	* The Original Code and all software distributed under the License are
	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23	/* $NetBSD: fparseln.c,v 1.9 1999/09/20 04:48:06 lukem Exp $ */
	24
	25	/*
	26	* Copyright (c) 1997 Christos Zoulas. All rights reserved.
	27	*
	28	* Redistribution and use in source and binary forms, with or without
	29	* modification, are permitted provided that the following conditions
	30	* are met:
	31	* 1. Redistributions of source code must retain the above copyright
	32	* notice, this list of conditions and the following disclaimer.
	33	* 2. Redistributions in binary form must reproduce the above copyright
	34	* notice, this list of conditions and the following disclaimer in the
	35	* documentation and/or other materials provided with the distribution.
	36	* 3. All advertising materials mentioning features or use of this software
	37	* must display the following acknowledgement:
	38	* This product includes software developed by Christos Zoulas.
	39	* 4. The name of the author may not be used to endorse or promote products
	40	* derived from this software without specific prior written permission.
	41	*
	42	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	43	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	44	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	45	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	46	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	47	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	48	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	49	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	50	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	51	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	52	*/
	53
	54	#include <sys/cdefs.h>
	55	__FBSDID("$FreeBSD: src/lib/libutil/fparseln.c,v 1.5 2002/03/21 23:52:49 obrien Exp $");
	56
	57	#include <sys/types.h>
	58	#include <assert.h>
	59	#include <errno.h>
	60	#include <stdio.h>
	61	#include <string.h>
	62	#include <stdlib.h>
	63	#include <util.h>
	64
	65	static int isescaped(const char , const char , int);
	66
	67	/* isescaped():
	68	* Return true if the character in *p that belongs to a string
	69	* that starts in *sp, is escaped by the escape character esc.
70	*/
71	static int
72	isescaped(sp, p, esc)
73	const char sp, p;
74	int esc;
75	{
76	const char *cp;
77	size_t ne;
78
79	#if 0
80	_DIAGASSERT(sp != NULL);
81	_DIAGASSERT(p != NULL);
82	#endif
83
84	/* No escape character */
85	if (esc == '\0')
86	return 1;
87
88	/* Count the number of escape characters that precede ours */
89	for (ne = 0, cp = p; --cp >= sp && *cp == esc; ne++)
90	continue;
91
92	/* Return true if odd number of escape characters */
93	return (ne & 1) != 0;
94	}
95
96
97	/* fparseln():
98	* Read a line from a file parsing continuations ending in \
99	* and eliminating trailing newlines, or comments starting with
100	* the comment char.
101	*/
102	char *
103	fparseln(fp, size, lineno, str, flags)
104	FILE *fp;
105	size_t *size;
106	size_t *lineno;
107	const char str[3];
108	int flags;
109	{
110	static const char dstr[3] = { '\\', '\\', '#' };
111
112	size_t s, len;
113	char *buf;
114	char ptr, cp;
115	int cnt;
116	char esc, con, nl, com;
117
118	#if 0
119	_DIAGASSERT(fp != NULL);
120	#endif
121
122	len = 0;
123	buf = NULL;
124	cnt = 1;
125
126	if (str == NULL)
127	str = dstr;
128
129	esc = str[0];
130	con = str[1];
131	com = str[2];
132	/*
133	* XXX: it would be cool to be able to specify the newline character,
134	* but unfortunately, fgetln does not let us
135	*/
136	nl = '\n';
137
138	while (cnt) {
139	cnt = 0;
140
141	if (lineno)
142	(*lineno)++;
143
144	if ((ptr = fgetln(fp, &s)) == NULL)
145	break;
146
147	if (s && com) { /* Check and eliminate comments */
148	for (cp = ptr; cp < ptr + s; cp++)
149	if (*cp == com && !isescaped(ptr, cp, esc)) {
150	s = cp - ptr;
151	cnt = s == 0 && buf == NULL;
152	break;
153	}
154	}
155
156	if (s && nl) { /* Check and eliminate newlines */
157	cp = &ptr[s - 1];
158
159	if (*cp == nl)
160	s--; /* forget newline */
161	}
162
163	if (s && con) { /* Check and eliminate continuations */
164	cp = &ptr[s - 1];
165
166	if (*cp == con && !isescaped(ptr, cp, esc)) {
167	s--; /* forget escape */
168	cnt = 1;
169	}
170	}
171
172	if (s == 0 && buf != NULL)
173	continue;
174
175	if ((cp = realloc(buf, len + s + 1)) == NULL) {
176	free(buf);
177	return NULL;
178	}
179	buf = cp;
180
181	(void) memcpy(buf + len, ptr, s);
182	len += s;
183	buf[len] = '\0';
184	}
185
186	if ((flags & FPARSELN_UNESCALL) != 0 && esc && buf != NULL &&
187	strchr(buf, esc) != NULL) {
188	ptr = cp = buf;
189	while (cp[0] != '\0') {
190	int skipesc;
191
192	while (cp[0] != '\0' && cp[0] != esc)
193	ptr++ = cp++;
194	if (cp[0] == '\0' \|\| cp[1] == '\0')
195	break;
196
197	skipesc = 0;
198	if (cp[1] == com)
199	skipesc += (flags & FPARSELN_UNESCCOMM);
200	if (cp[1] == con)
201	skipesc += (flags & FPARSELN_UNESCCONT);
202	if (cp[1] == esc)
203	skipesc += (flags & FPARSELN_UNESCESC);
204	if (cp[1] != com && cp[1] != con && cp[1] != esc)
205	skipesc = (flags & FPARSELN_UNESCREST);
206
207	if (skipesc)
208	cp++;
209	else
210	ptr++ = cp++;
211	ptr++ = cp++;
212	}
213	*ptr = '\0';
214	len = strlen(buf);
215	}
216
217	if (size)
218	*size = len;
219	return buf;
220	}
221
222	#ifdef TEST
223
224	int main(int, char **);
225
226	int
227	main(argc, argv)
228	int argc;
229	char **argv;
230	{
231	char *ptr;
232	size_t size, line;
233
234	line = 0;
235	while ((ptr = fparseln(stdin, &size, &line, NULL,
236	FPARSELN_UNESCALL)) != NULL)
237	printf("line %d (%d) \|%s\|\n", line, size, ptr);
238	return 0;
239	}
240
241	/*
242
243	# This is a test
244	line 1
245	line 2 \
246	line 3 # Comment
247	line 4 \# Not comment \\\\
248
249	# And a comment \
250	line 5 \\\
251	line 6
252
253	*/
254
255	#endif /* TEST */