xref: /titanic_41/usr/src/lib/libc/port/gen/deflt.c (revision 95efa359b507db290a2484b8f615822b1e06096f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*	Copyright (c) 1987, 1988 Microsoft Corporation	*/
31 /*	  All Rights Reserved	*/
32 
33 #pragma ident	"%Z%%M%	%I%	%E% SMI"
34 
35 #include "lint.h"
36 #include "libc.h"
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <deflt.h>
40 #include <sys/types.h>
41 #include <string.h>
42 #include <ctype.h>
43 #include <unistd.h>
44 #include "tsd.h"
45 
46 #define	TSTBITS(flags, mask)	(((flags) & (mask)) == (mask))
47 
48 static void strip_quotes(char *);
49 
50 struct thr_data {
51 	int  Dcflags;	/* [re-]initialized on each call to defopen() */
52 	FILE *fp;
53 	char *buf;
54 };
55 
56 #define	BUFFERSIZE	1024
57 
58 /*
59  * destructor for per-thread data, registered with tsdalloc()
60  */
61 static void
62 free_thr_data(void *arg)
63 {
64 	struct thr_data *thr_data = (struct thr_data *)arg;
65 
66 	if (thr_data->fp) {
67 		(void) fclose(thr_data->fp);
68 		thr_data->fp = NULL;
69 	}
70 	if (thr_data->buf) {
71 		lfree(thr_data->buf, BUFFERSIZE);
72 		thr_data->buf = NULL;
73 	}
74 }
75 
76 /*
77  * get the per-thread-data-item for the calling thread
78  */
79 static struct thr_data *
80 get_thr_data(void)
81 {
82 	struct thr_data *thr_data =
83 	    tsdalloc(_T_DEFREAD, sizeof (*thr_data), free_thr_data);
84 
85 	return (thr_data);
86 }
87 
88 /*
89  *	defopen() - declare defopen filename
90  *
91  *	defopen(fn)
92  *		char *fn
93  *
94  *	If 'fn' is non-null; it is a full pathname of a file
95  *	which becomes the one read by subsequent defread() calls.
96  *	If 'fn' is null the defopen file is closed.
97  *
98  *	see defread() for more details.
99  *
100  *	EXIT    returns 0 if ok
101  *		returns -1 if error
102  */
103 int
104 defopen(char *fn)
105 {
106 	struct thr_data *thr_data = get_thr_data();
107 
108 	if (thr_data == NULL)
109 		return (-1);
110 
111 	if (thr_data->fp != NULL) {
112 		(void) fclose(thr_data->fp);
113 		thr_data->fp = NULL;
114 	}
115 
116 	if (fn == NULL)
117 		return (0);
118 
119 	if ((thr_data->fp = fopen(fn, "rF")) == NULL)
120 		return (-1);
121 
122 	/*
123 	 * We allocate the big buffer only if the fopen() succeeds.
124 	 * Notice that we deallocate the buffer only when the thread exits.
125 	 * There are misguided applications that assume that data returned
126 	 * by defread() continues to exist after defopen(NULL) is called.
127 	 */
128 	if (thr_data->buf == NULL &&
129 	    (thr_data->buf = lmalloc(BUFFERSIZE)) == NULL) {
130 		(void) fclose(thr_data->fp);
131 		thr_data->fp = NULL;
132 		return (-1);
133 	}
134 
135 	thr_data->Dcflags = DC_STD;
136 
137 	return (0);
138 }
139 
140 /*
141  *	defread() - read an entry from the defopen file
142  *
143  *	defread(cp)
144  *		char *cp
145  *
146  *	The defopen data file must have been previously opened by
147  *	defopen().  defread scans the data file looking for a line
148  *	which begins with the string '*cp'.  If such a line is found,
149  *	defread returns a pointer to the first character following
150  *	the matched string (*cp).  If no line is found or no file
151  *	is open, defread() returns NULL.
152  *
153  *	Note that there is no way to simulatniously peruse multiple
154  *	defopen files; since there is no way of indicating 'which one'
155  *	to defread().  If you want to peruse a secondary file you must
156  *	recall defopen().  If you need to go back to the first file,
157  *	you must call defopen() again.
158  */
159 char *
160 defread(char *cp)
161 {
162 	struct thr_data *thr_data = get_thr_data();
163 	int (*compare)(const char *, const char *, size_t);
164 	char *buf_tmp, *ret_ptr = NULL;
165 	size_t off, patlen;
166 
167 	if (thr_data == NULL || thr_data->fp == NULL)
168 		return (NULL);
169 
170 	compare = TSTBITS(thr_data->Dcflags, DC_CASE) ? strncmp : strncasecmp;
171 	patlen = strlen(cp);
172 
173 	if (!TSTBITS(thr_data->Dcflags, DC_NOREWIND))
174 		rewind(thr_data->fp);
175 
176 	while (fgets(thr_data->buf, BUFFERSIZE, thr_data->fp)) {
177 		for (buf_tmp = thr_data->buf; *buf_tmp == ' '; buf_tmp++)
178 			;
179 		off = strlen(buf_tmp) - 1;
180 		if (buf_tmp[off] == '\n')
181 			buf_tmp[off] = 0;
182 		else
183 			break;	/* line too long */
184 		if ((*compare)(cp, buf_tmp, patlen) == 0) {
185 			/* found it */
186 			/* strip quotes if requested */
187 			if (TSTBITS(thr_data->Dcflags, DC_STRIP_QUOTES)) {
188 				strip_quotes(buf_tmp);
189 			}
190 			ret_ptr = &buf_tmp[patlen];
191 			break;
192 		}
193 	}
194 
195 	return (ret_ptr);
196 }
197 
198 /*
199  *	defcntl -- default control
200  *
201  *	SYNOPSIS
202  *	  oldflags = defcntl(cmd, arg);
203  *
204  *	ENTRY
205  *	  cmd		Command.  One of DC_GET, DC_SET.
206  *	  arg		Depends on command.  If DC_GET, ignored.  If
207  *		DC_GET, new flags value, created by ORing the DC_* bits.
208  *	RETURN
209  *	  oldflags	Old value of flags.  -1 on error.
210  *	NOTES
211  *	  Currently only one bit of flags implemented, namely respect/
212  *	  ignore case.  The routine is as general as it is so that we
213  *	  leave our options open.  E.g. we might want to specify rewind/
214  *	  norewind before each defread.
215  */
216 
217 int
218 defcntl(int cmd, int newflags)
219 {
220 	struct thr_data *thr_data = get_thr_data();
221 	int  oldflags;
222 
223 	if (thr_data == NULL)
224 		return (-1);
225 
226 	switch (cmd) {
227 	case DC_GETFLAGS:		/* query */
228 		oldflags = thr_data->Dcflags;
229 		break;
230 	case DC_SETFLAGS:		/* set */
231 		oldflags = thr_data->Dcflags;
232 		thr_data->Dcflags = newflags;
233 		break;
234 	default:			/* error */
235 		oldflags = -1;
236 		break;
237 	}
238 
239 	return (oldflags);
240 }
241 
242 /*
243  *	strip_quotes -- strip double (") or single (') quotes from a buffer
244  *
245  *	ENTRY
246  *	  ptr		initial string
247  *
248  *	EXIT
249  *	  ptr		string with quotes (if any) removed
250  */
251 static void
252 strip_quotes(char *ptr)
253 {
254 	char *strip_ptr = NULL;
255 
256 	while (*ptr != '\0') {
257 		if ((*ptr == '"') || (*ptr == '\'')) {
258 			if (strip_ptr == NULL)
259 				strip_ptr = ptr;	/* skip over quote */
260 		} else {
261 			if (strip_ptr != NULL) {
262 				*strip_ptr = *ptr;
263 				strip_ptr++;
264 			}
265 		}
266 		ptr++;
267 	}
268 	if (strip_ptr != NULL) {
269 		*strip_ptr = '\0';
270 	}
271 }
272