1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * ------+---------+---------+---------+---------+---------+---------+---------*
5  * Copyright (c) 2001  - Garance Alistair Drosehn <gad@FreeBSD.org>.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *   1. Redistributions of source code must retain the above copyright
12  *      notice, this list of conditions and the following disclaimer.
13  *   2. Redistributions in binary form must reproduce the above copyright
14  *      notice, this list of conditions and the following disclaimer in the
15  *      documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * The views and conclusions contained in the software and documentation
30  * are those of the authors and should not be interpreted as representing
31  * official policies, either expressed or implied, of the FreeBSD Project.
32  *
33  * ------+---------+---------+---------+---------+---------+---------+---------*
34  */
35 
36 #include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
37 __FBSDID("$FreeBSD$");
38 
39 #include <sys/types.h>
40 
41 #include <ctype.h>
42 #include <err.h>
43 #include <errno.h>
44 #include <grp.h>
45 #include <stdio.h>
46 #include <string.h>
47 #include <stdlib.h>
48 #include <unistd.h>
49 
50 #include <sys/param.h>		/* needed for lp.h but not used here */
51 #include <dirent.h>		/* ditto */
52 #include "lp.h"
53 #include "lp.local.h"
54 #include "skimprintcap.h"
55 
56 /*
57  * Save the canonical queue name of the entry that is currently being
58  * scanned, in case a warning message is printed for the current queue.
59  * Only the first 'QENTRY_MAXLEN' characters will be saved, since this
60  * is only for warning messages.   The variable includes space for the
61  * string " (entry " and a trailing ")", when the scanner is in the
62  * middle of an entry.  When the scanner is not in a specific entry,
63  * the variable will be the a null string.
64  */
65 #define QENTRY_MAXLEN	30
66 #define QENTRY_PREFIX	" (entry "
67 static char	 skim_entryname[sizeof(QENTRY_PREFIX) + QENTRY_MAXLEN + 2];
68 
69 /*
70  * isgraph is defined to work on an 'int', in the range 0 to 255, plus EOF.
71  * Define a wrapper which can take 'char', either signed or unsigned.
72  */
73 #define isgraphch(Anychar)    isgraph(((int) Anychar) & 255)
74 
75 struct skiminfo *
76 skim_printcap(const char *pcap_fname, int verbosity)
77 {
78 	struct skiminfo *skinf;
79 	char buff[BUFSIZ];
80 	char *ch, *curline, *endfield, *lastchar;
81 	FILE *pc_file;
82 	int missing_nl;
83 	enum {NO_CONTINUE, WILL_CONTINUE, BAD_CONTINUE} is_cont, had_cont;
84 	enum {CMNT_LINE, ENTRY_LINE, TAB_LINE, TABERR_LINE} is_type, had_type;
85 
86 	skinf = malloc(sizeof(struct skiminfo));
87 	if (skinf == NULL)
88 		return (NULL);
89 	memset(skinf, 0, sizeof(struct skiminfo));
90 
91 	pc_file = fopen(pcap_fname, "r");
92 	if (pc_file == NULL) {
93 		warn("fopen(%s)", pcap_fname);
94 		skinf->fatalerr++;
95 		return (skinf);		/* fatal error */
96 	}
97 
98 	skim_entryname[0] = '0';
99 
100 	is_cont = NO_CONTINUE;
101 	is_type = CMNT_LINE;
102 	errno = 0;
103 	curline = fgets(buff, sizeof(buff), pc_file);
104 	while (curline != NULL) {
105 		skinf->lines++;
106 
107 		/* Check for the expected newline char, and remove it */
108 		missing_nl = 0;
109 		lastchar = strchr(curline, '\n');
110 		if (lastchar != NULL)
111 			*lastchar = '\0';
112 		else {
113 			lastchar = strchr(curline, '\0');
114 			missing_nl = 1;
115 		}
116 		if (curline < lastchar)
117 			lastchar--;
118 
119 		/*
120 		 * Check for `\' (continuation-character) at end of line.
121 		 * If there is none, then trim off spaces and check again.
122 		 * This would be a bad line because it looks like it is
123 		 * continued, but it will not be treated that way.
124 		 */
125 		had_cont = is_cont;
126 		is_cont = NO_CONTINUE;
127 		if (*lastchar == '\\') {
128 			is_cont = WILL_CONTINUE;
129 			lastchar--;
130 		} else {
131 			while ((curline < lastchar) && !isgraphch(*lastchar))
132 				lastchar--;
133 			if (*lastchar == '\\')
134 				is_cont = BAD_CONTINUE;
135 		}
136 
137 		had_type = is_type;
138 		is_type = CMNT_LINE;
139 		switch (*curline) {
140 		case '\0':	/* treat zero-length line as comment */
141 		case '#':
142 			skinf->comments++;
143 			break;
144 		case ' ':
145 		case '\t':
146 			is_type = TAB_LINE;
147 			break;
148 		default:
149 			is_type = ENTRY_LINE;
150 			skinf->entries++;
151 
152 			/* pick up the queue name, to use in warning messages */
153 			ch = curline;
154 			while ((ch <= lastchar) && (*ch != ':') && (*ch != '|'))
155 				ch++;
156 			ch--;			/* last char of queue name */
157 			strcpy(skim_entryname, QENTRY_PREFIX);
158 			if ((ch - curline) > QENTRY_MAXLEN) {
159 				strncat(skim_entryname, curline, QENTRY_MAXLEN
160 				    - 1);
161 				strcat(skim_entryname, "+");
162 			} else {
163 				strncat(skim_entryname, curline, (ch - curline
164 				    + 1));
165 			}
166 			strlcat(skim_entryname, ")", sizeof(skim_entryname));
167 			break;
168 		}
169 
170 		/*
171 		 * Check to see if the previous line was a bad contination
172 		 * line.  The check is delayed until now so a warning message
173 		 * is not printed when a "bad continuation" is on a comment
174 		 * line, and it just "continues" into another comment line.
175 		*/
176 		if (had_cont == BAD_CONTINUE) {
177 			if ((had_type != CMNT_LINE) || (is_type != CMNT_LINE) ||
178 			    (verbosity > 1)) {
179 				skinf->warnings++;
180 				warnx("Warning: blanks after trailing '\\',"
181 				    " at line %d%s", skinf->lines - 1,
182 				    skim_entryname);
183 			}
184 		}
185 
186 		/* If we are no longer in an entry, then forget the name */
187 		if ((had_cont != WILL_CONTINUE) && (is_type != ENTRY_LINE)) {
188 			skim_entryname[0] = '\0';
189 		}
190 
191 		/*
192 		 * Print out warning for missing newline, done down here
193 		 * so we are sure to have the right entry-name for it.
194 		*/
195 		if (missing_nl) {
196 			skinf->warnings++;
197 			warnx("Warning: No newline at end of line %d%s",
198 			    skinf->lines, skim_entryname);
199 		}
200 
201 		/*
202 		 * Check for start-of-entry lines which do not include a
203 		 * ":" character (to indicate the end of the name field).
204 		 * This can cause standard printcap processing to ignore
205 		 * ALL of the following lines.
206 		 * XXXXX - May need to allow for the list-of-names to
207 		 *         continue on to the following line...
208 		*/
209 		if (is_type == ENTRY_LINE) {
210 			endfield = strchr(curline, ':');
211 			if (endfield == NULL) {
212 				skinf->warnings++;
213 				warnx("Warning: No ':' to terminate name-field"
214 				    " at line %d%s", skinf->lines,
215 				    skim_entryname);
216 			}
217 		}
218 
219 		/*
220 		 * Now check for cases where this line is (or is-not) a
221 		 * continuation of the previous line, and a person skimming
222 		 * the file would assume it is not (or is) a continuation.
223 		*/
224 		switch (had_cont) {
225 		case NO_CONTINUE:
226 		case BAD_CONTINUE:
227 			if (is_type == TAB_LINE) {
228 				skinf->warnings++;
229 				warnx("Warning: values-line after line with"
230 				    " NO trailing '\\', at line %d%s",
231 				    skinf->lines, skim_entryname);
232 			}
233 			break;
234 
235 		case WILL_CONTINUE:
236 			if (is_type == ENTRY_LINE) {
237 				skinf->warnings++;
238 				warnx("Warning: new entry starts after line"
239 				    " with trailing '\\', at line %d%s",
240 				    skinf->lines, skim_entryname);
241 			}
242 			break;
243 		}
244 
245 		/* get another line from printcap and repeat loop */
246 		curline = fgets(buff, sizeof(buff), pc_file);
247 	}
248 
249 	if (errno != 0) {
250 		warn("fgets(%s)", pcap_fname);
251 		skinf->fatalerr++;		/* fatal error */
252 	}
253 
254 	if (skinf->warnings > 0)
255 		warnx("%4d warnings from skimming %s", skinf->warnings,
256 		    pcap_fname);
257 
258 	if (verbosity)
259 		warnx("%4d lines (%d comments), %d entries for %s",
260 		    skinf->lines, skinf->comments, skinf->entries, pcap_fname);
261 
262 	fclose(pc_file);
263 	return (skinf);
264 }
265