1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/* lexer (lexical analyzer) for control files
* Copyright (C) 1998-2001 D. Hugh Redelmeier.
*
* 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. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*
* RCSID $Id$
*/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <errno.h>
#include <freeswan.h>
#include "constants.h"
#include "defs.h"
#include "log.h"
#include "whack.h" /* for RC_LOG_SERIOUS */
#include "lex.h"
struct file_lex_position *flp = NULL;
/* Open a file for lexical processing.
* new_flp and name must point into storage with will live
* at least until the file is closed.
*/
bool
lexopen(struct file_lex_position *new_flp, const char *name, bool optional)
{
FILE *f = fopen(name, "r");
if (f == NULL)
{
if (!optional || errno != ENOENT)
log_errno((e, "could not open \"%s\"", name));
return FALSE;
}
else
{
new_flp->previous = flp;
flp = new_flp;
flp->filename = name;
flp->fp = f;
flp->lino = 0;
flp->bdry = B_none;
flp->cur = flp->buffer; /* nothing loaded yet */
flp->under = *flp->cur = '\0';
(void) shift(); /* prime tok */
return TRUE;
}
}
void
lexclose(void)
{
fclose(flp->fp);
flp = flp->previous;
}
/* Token decoding: shift() loads the next token into tok.
* Iff a token starts at the left margin, it is considered
* to be the first in a record. We create a special condition,
* Record Boundary (analogous to EOF), just before such a token.
* We are unwilling to shift through a record boundary:
* it must be overridden first.
* Returns FALSE iff Record Boundary or EOF (i.e. no token);
* tok will then be NULL.
*/
char *tok;
#define tokeq(s) (streq(tok, (s)))
#define tokeqword(s) (strcasecmp(tok, (s)) == 0)
bool
shift(void)
{
char *p = flp->cur;
char *sor = NULL; /* start of record for any new lines */
passert(flp->bdry == B_none);
*p = flp->under;
flp->under = '\0';
for (;;)
{
switch (*p)
{
case '\0': /* end of line */
case '#': /* comment to end of line: treat as end of line */
/* get the next line */
if (fgets(flp->buffer, sizeof(flp->buffer)-1, flp->fp) == NULL)
{
flp->bdry = B_file;
tok = flp->cur = NULL;
return FALSE;
}
else
{
/* strip trailing whitespace, including \n */
for (p = flp->buffer+strlen(flp->buffer)-1
; p>flp->buffer && isspace(p[-1]); p--)
;
*p = '\0';
flp->lino++;
sor = p = flp->buffer;
}
break; /* try again for a token */
case ' ': /* whitespace */
case '\t':
p++;
break; /* try again for a token */
case '"': /* quoted token */
case '\'':
if (p != sor)
{
/* we have a quoted token: note and advance to its end */
tok = p;
p = strchr(p+1, *p);
if (p == NULL)
{
loglog(RC_LOG_SERIOUS, "\"%s\" line %d: unterminated string"
, flp->filename, flp->lino);
p = tok + strlen(tok);
}
else
{
p++; /* include delimiter in token */
}
/* remember token delimiter and replace with '\0' */
flp->under = *p;
*p = '\0';
flp->cur = p;
return TRUE;
}
/* FALL THROUGH */
default:
if (p != sor)
{
/* we seem to have a token: note and advance to its end */
tok = p;
if (p[0] == '0' && p[1] == 't')
{
/* 0t... token goes to end of line */
p += strlen(p);
}
else
{
/* "ordinary" token: up to whitespace or end of line */
do {
p++;
} while (*p != '\0' && !isspace(*p))
;
/* fudge to separate ':' from a preceding adjacent token */
if (p-1 > tok && p[-1] == ':')
p--;
}
/* remember token delimiter and replace with '\0' */
flp->under = *p;
*p = '\0';
flp->cur = p;
return TRUE;
}
/* we have a start-of-record: return it, deferring "real" token */
flp->bdry = B_record;
tok = NULL;
flp->under = *p;
flp->cur = p;
return FALSE;
}
}
}
/* ensures we are at a Record (or File) boundary, optionally warning if not */
bool
flushline(const char *m)
{
if (flp->bdry != B_none)
{
return TRUE;
}
else
{
if (m != NULL)
loglog(RC_LOG_SERIOUS, "\"%s\" line %d: %s", flp->filename, flp->lino, m);
do ; while (shift());
return FALSE;
}
}
|
