1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/types.h>
38 
39 #include <ctype.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <grp.h>
43 #include <stdio.h>
44 #include <string.h>
45 #include <stdlib.h>
46 #include <unistd.h>
47 
48 #include <sys/param.h>		/* needed for lp.h but not used here */
49 #include <dirent.h>		/* ditto */
50 #include "lp.h"
51 #include "lp.local.h"
52 #include "skimprintcap.h"
53 
54 /*
55  * Save the canonical queue name of the entry that is currently being
56  * scanned, in case a warning message is printed for the current queue.
57  * Only the first 'QENTRY_MAXLEN' characters will be saved, since this
58  * is only for warning messages.   The variable includes space for the
59  * string " (entry " and a trailing ")", when the scanner is in the
60  * middle of an entry.  When the scanner is not in a specific entry,
61  * the variable will be the a null string.
62  */
63 #define QENTRY_MAXLEN	30
64 #define QENTRY_PREFIX	" (entry "
65 static char	 skim_entryname[sizeof(QENTRY_PREFIX) + QENTRY_MAXLEN + 2];
66 
67 /*
68  * isgraph is defined to work on an 'int', in the range 0 to 255, plus EOF.
69  * Define a wrapper which can take 'char', either signed or unsigned.
70  */
71 #define isgraphch(Anychar)    isgraph(((int) Anychar) & 255)
72 
73 struct skiminfo *
74 skim_printcap(const char *pcap_fname, int verbosity)
75 {
76 	struct skiminfo *skinf;
77 	char buff[BUFSIZ];
78 	char *ch, *curline, *endfield, *lastchar;
79 	FILE *pc_file;
80 	int missing_nl;
81 	enum {NO_CONTINUE, WILL_CONTINUE, BAD_CONTINUE} is_cont, had_cont;
82 	enum {CMNT_LINE, ENTRY_LINE, TAB_LINE, TABERR_LINE} is_type, had_type;
83 
84 	skinf = malloc(sizeof(struct skiminfo));
85 	if (skinf == NULL)
86 		return (NULL);
87 	memset(skinf, 0, sizeof(struct skiminfo));
88 
89 	pc_file = fopen(pcap_fname, "r");
90 	if (pc_file == NULL) {
91 		warn("fopen(%s)", pcap_fname);
92 		skinf->fatalerr++;
93 		return (skinf);		/* fatal error */
94 	}
95 
96 	skim_entryname[0] = '0';
97 
98 	is_cont = NO_CONTINUE;
99 	is_type = CMNT_LINE;
100 	errno = 0;
101 	curline = fgets(buff, sizeof(buff), pc_file);
102 	while (curline != NULL) {
103 		skinf->lines++;
104 
105 		/* Check for the expected newline char, and remove it */
106 		missing_nl = 0;
107 		lastchar = strchr(curline, '\n');
108 		if (lastchar != NULL)
109 			*lastchar = '\0';
110 		else {
111 			lastchar = strchr(curline, '\0');
112 			missing_nl = 1;
113 		}
114 		if (curline < lastchar)
115 			lastchar--;
116 
117 		/*
118 		 * Check for `\' (continuation-character) at end of line.
119 		 * If there is none, then trim off spaces and check again.
120 		 * This would be a bad line because it looks like it is
121 		 * continued, but it will not be treated that way.
122 		 */
123 		had_cont = is_cont;
124 		is_cont = NO_CONTINUE;
125 		if (*lastchar == '\\') {
126 			is_cont = WILL_CONTINUE;
127 			lastchar--;
128 		} else {
129 			while ((curline < lastchar) && !isgraphch(*lastchar))
130 				lastchar--;
131 			if (*lastchar == '\\')
132 				is_cont = BAD_CONTINUE;
133 		}
134 
135 		had_type = is_type;
136 		is_type = CMNT_LINE;
137 		switch (*curline) {
138 		case '\0':	/* treat zero-length line as comment */
139 		case '#':
140 			skinf->comments++;
141 			break;
142 		case ' ':
143 		case '\t':
144 			is_type = TAB_LINE;
145 			break;
146 		default:
147 			is_type = ENTRY_LINE;
148 			skinf->entries++;
149 
150 			/* pick up the queue name, to use in warning messages */
151 			ch = curline;
152 			while ((ch <= lastchar) && (*ch != ':') && (*ch != '|'))
153 				ch++;
154 			ch--;			/* last char of queue name */
155 			strcpy(skim_entryname, QENTRY_PREFIX);
156 			if ((ch - curline) > QENTRY_MAXLEN) {
157 				strncat(skim_entryname, curline, QENTRY_MAXLEN
158 				    - 1);
159 				strcat(skim_entryname, "+");
160 			} else {
161 				strncat(skim_entryname, curline, (ch - curline
162 				    + 1));
163 			}
164 			strlcat(skim_entryname, ")", sizeof(skim_entryname));
165 			break;
166 		}
167 
168 		/*
169 		 * Check to see if the previous line was a bad contination
170 		 * line.  The check is delayed until now so a warning message
171 		 * is not printed when a "bad continuation" is on a comment
172 		 * line, and it just "continues" into another comment line.
173 		*/
174 		if (had_cont == BAD_CONTINUE) {
175 			if ((had_type != CMNT_LINE) || (is_type != CMNT_LINE) ||
176 			    (verbosity > 1)) {
177 				skinf->warnings++;
178 				warnx("Warning: blanks after trailing '\\',"
179 				    " at line %d%s", skinf->lines - 1,
180 				    skim_entryname);
181 			}
182 		}
183 
184 		/* If we are no longer in an entry, then forget the name */
185 		if ((had_cont != WILL_CONTINUE) && (is_type != ENTRY_LINE)) {
186 			skim_entryname[0] = '\0';
187 		}
188 
189 		/*
190 		 * Print out warning for missing newline, done down here
191 		 * so we are sure to have the right entry-name for it.
192 		*/
193 		if (missing_nl) {
194 			skinf->warnings++;
195 			warnx("Warning: No newline at end of line %d%s",
196 			    skinf->lines, skim_entryname);
197 		}
198 
199 		/*
200 		 * Check for start-of-entry lines which do not include a
201 		 * ":" character (to indicate the end of the name field).
202 		 * This can cause standard printcap processing to ignore
203 		 * ALL of the following lines.
204 		 * XXXXX - May need to allow for the list-of-names to
205 		 *         continue on to the following line...
206 		*/
207 		if (is_type == ENTRY_LINE) {
208 			endfield = strchr(curline, ':');
209 			if (endfield == NULL) {
210 				skinf->warnings++;
211 				warnx("Warning: No ':' to terminate name-field"
212 				    " at line %d%s", skinf->lines,
213 				    skim_entryname);
214 			}
215 		}
216 
217 		/*
218 		 * Now check for cases where this line is (or is-not) a
219 		 * continuation of the previous line, and a person skimming
220 		 * the file would assume it is not (or is) a continuation.
221 		*/
222 		switch (had_cont) {
223 		case NO_CONTINUE:
224 		case BAD_CONTINUE:
225 			if (is_type == TAB_LINE) {
226 				skinf->warnings++;
227 				warnx("Warning: values-line after line with"
228 				    " NO trailing '\\', at line %d%s",
229 				    skinf->lines, skim_entryname);
230 			}
231 			break;
232 
233 		case WILL_CONTINUE:
234 			if (is_type == ENTRY_LINE) {
235 				skinf->warnings++;
236 				warnx("Warning: new entry starts after line"
237 				    " with trailing '\\', at line %d%s",
238 				    skinf->lines, skim_entryname);
239 			}
240 			break;
241 		}
242 
243 		/* get another line from printcap and repeat loop */
244 		curline = fgets(buff, sizeof(buff), pc_file);
245 	}
246 
247 	if (errno != 0) {
248 		warn("fgets(%s)", pcap_fname);
249 		skinf->fatalerr++;		/* fatal error */
250 	}
251 
252 	if (skinf->warnings > 0)
253 		warnx("%4d warnings from skimming %s", skinf->warnings,
254 		    pcap_fname);
255 
256 	if (verbosity)
257 		warnx("%4d lines (%d comments), %d entries for %s",
258 		    skinf->lines, skinf->comments, skinf->entries, pcap_fname);
259 
260 	fclose(pc_file);
261 	return (skinf);
262 }
263