1 /*
2 Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>
3 This program and the accompanying materials are licensed and made available
4 under the terms and conditions of the BSD License that accompanies this
5 distribution. The full text of the license may be found at
6 http://opensource.org/licenses/bsd-license.
7
8 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
9 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
10
11 * Copyright (c) 1997 Christos Zoulas. All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 * must display the following acknowledgement:
23 * This product includes software developed by Christos Zoulas.
24 * 4. The name of the author may not be used to endorse or promote products
25 * derived from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37
38 NetBSD: fparseln.c,v 1.5 2004/06/20 22:20:15 jmc Exp
39 */
40 #include <LibConfig.h>
41 #include <sys/EfiCdefs.h>
42
43 #include "namespace.h"
44
45 #include <assert.h>
46 #include <errno.h>
47 #include <stdio.h>
48 #include <string.h>
49 #include <stdlib.h>
50
51 #ifdef __weak_alias
52 __weak_alias(fparseln,_fparseln)
53 #endif
54
55 #if ! HAVE_FPARSELN
56
57 #ifndef HAVE_NBTOOL_CONFIG_H
58 #include "reentrant.h"
59 #include "local.h"
60 #else
61 #define FLOCKFILE(fp)
62 #define FUNLOCKFILE(fp)
63 #endif
64
65 #if defined(_REENTRANT) && !HAVE_NBTOOL_CONFIG_H
66 #define __fgetln(f, l) __fgetstr(f, l, '\n')
67 #else
68 #define __fgetln(f, l) fgetln(f, l)
69 #endif
70
71 static int isescaped(const char *, const char *, int);
72
73 /* isescaped():
74 * Return true if the character in *p that belongs to a string
75 * that starts in *sp, is escaped by the escape character esc.
76 */
77 static int
isescaped(const char * sp,const char * p,int esc)78 isescaped(const char *sp, const char *p, int esc)
79 {
80 const char *cp;
81 size_t ne;
82
83 _DIAGASSERT(sp != NULL);
84 _DIAGASSERT(p != NULL);
85
86 /* No escape character */
87 if (esc == '\0')
88 return 1;
89
90 /* Count the number of escape characters that precede ours */
91 for (ne = 0, cp = p; --cp >= sp && *cp == esc; ne++)
92 continue;
93
94 /* Return true if odd number of escape characters */
95 return (ne & 1) != 0;
96 }
97
98
99 /* fparseln():
100 * Read a line from a file parsing continuations ending in \
101 * and eliminating trailing newlines, or comments starting with
102 * the comment char.
103 */
104 char *
fparseln(FILE * fp,size_t * size,size_t * lineno,const char str[3],int flags)105 fparseln(FILE *fp, size_t *size, size_t *lineno, const char str[3], int flags)
106 {
107 static const char dstr[3] = { '\\', '\\', '#' };
108
109 size_t s, len;
110 char *buf;
111 char *ptr, *cp;
112 int cnt;
113 char esc, con, nl, com;
114
115 _DIAGASSERT(fp != NULL);
116 if(fp == NULL) {
117 errno = EINVAL;
118 return (NULL);
119 }
120
121 len = 0;
122 buf = NULL;
123 cnt = 1;
124
125 if (str == NULL)
126 str = dstr;
127
128 esc = str[0];
129 con = str[1];
130 com = str[2];
131 /*
132 * XXX: it would be cool to be able to specify the newline character,
133 * but unfortunately, fgetln does not let us
134 */
135 nl = '\n';
136
137 FLOCKFILE(fp);
138
139 while (cnt) {
140 cnt = 0;
141
142 if (lineno)
143 (*lineno)++;
144
145 if ((ptr = __fgetln(fp, &s)) == NULL)
146 break;
147
148 if (s && com) { /* Check and eliminate comments */
149 for (cp = ptr; cp < ptr + s; cp++)
150 if (*cp == com && !isescaped(ptr, cp, esc)) {
151 s = cp - ptr;
152 cnt = s == 0 && buf == NULL;
153 break;
154 }
155 }
156
157 if (s && nl) { /* Check and eliminate newlines */
158 cp = &ptr[s - 1];
159
160 if (*cp == nl)
161 s--; /* forget newline */
162 }
163
164 if (s && con) { /* Check and eliminate continuations */
165 cp = &ptr[s - 1];
166
167 if (*cp == con && !isescaped(ptr, cp, esc)) {
168 s--; /* forget escape */
169 cnt = 1;
170 }
171 }
172
173 if (s == 0 && buf != NULL)
174 continue;
175
176 if ((cp = realloc(buf, len + s + 1)) == NULL) {
177 FUNLOCKFILE(fp);
178 free(buf);
179 return NULL;
180 }
181 buf = cp;
182
183 (void) memcpy(buf + len, ptr, s);
184 len += s;
185 buf[len] = '\0';
186 }
187
188 FUNLOCKFILE(fp);
189
190 if ((flags & FPARSELN_UNESCALL) != 0 && esc && buf != NULL &&
191 strchr(buf, esc) != NULL) {
192 ptr = cp = buf;
193 while (cp[0] != '\0') {
194 int skipesc;
195
196 while (cp[0] != '\0' && cp[0] != esc)
197 *ptr++ = *cp++;
198 if (cp[0] == '\0' || cp[1] == '\0')
199 break;
200
201 skipesc = 0;
202 if (cp[1] == com)
203 skipesc += (flags & FPARSELN_UNESCCOMM);
204 if (cp[1] == con)
205 skipesc += (flags & FPARSELN_UNESCCONT);
206 if (cp[1] == esc)
207 skipesc += (flags & FPARSELN_UNESCESC);
208 if (cp[1] != com && cp[1] != con && cp[1] != esc)
209 skipesc = (flags & FPARSELN_UNESCREST);
210
211 if (skipesc)
212 cp++;
213 else
214 *ptr++ = *cp++;
215 *ptr++ = *cp++;
216 }
217 *ptr = '\0';
218 len = strlen(buf);
219 }
220
221 if (size)
222 *size = len;
223 return buf;
224 }
225
226 #ifdef TEST
227
228 int main(int, char **);
229
230 int
main(int argc,char ** argv)231 main(int argc, char **argv)
232 {
233 char *ptr;
234 size_t size, line;
235
236 line = 0;
237 while ((ptr = fparseln(stdin, &size, &line, NULL,
238 FPARSELN_UNESCALL)) != NULL)
239 printf("line %d (%d) |%s|\n", line, size, ptr);
240 return 0;
241 }
242
243 /*
244
245 # This is a test
246 line 1
247 line 2 \
248 line 3 # Comment
249 line 4 \# Not comment \\\\
250
251 # And a comment \
252 line 5 \\\
253 line 6
254
255 */
256
257 #endif /* TEST */
258 #endif /* ! HAVE_FPARSELN */
259