xref: /freebsd/usr.bin/hexdump/display.c (revision aa24f48b361effe51163877d84f1b70d32b77e04)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 
30 #ifndef lint
31 #if 0
32 static char sccsid[] = "@(#)display.c	8.1 (Berkeley) 6/6/93";
33 #endif
34 #endif /* not lint */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/capsicum.h>
40 #include <sys/stat.h>
41 
42 #include <capsicum_helpers.h>
43 #include <ctype.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include "hexdump.h"
51 
52 enum _vflag vflag = FIRST;
53 
54 static off_t address;			/* address/offset in stream */
55 static off_t eaddress;			/* end address */
56 
57 static void print(PR *, u_char *);
58 
59 void
60 display(void)
61 {
62 	FS *fs;
63 	FU *fu;
64 	PR *pr;
65 	int cnt;
66 	u_char *bp;
67 	off_t saveaddress;
68 	u_char savech, *savebp;
69 
70 	savech = 0;
71 	while ((bp = get()))
72 	    for (fs = fshead, savebp = bp, saveaddress = address; fs;
73 		fs = fs->nextfs, bp = savebp, address = saveaddress)
74 		    for (fu = fs->nextfu; fu; fu = fu->nextfu) {
75 			if (fu->flags&F_IGNORE)
76 				break;
77 			for (cnt = fu->reps; cnt; --cnt)
78 			    for (pr = fu->nextpr; pr; address += pr->bcnt,
79 				bp += pr->bcnt, pr = pr->nextpr) {
80 				    if (eaddress && address >= eaddress &&
81 					!(pr->flags & (F_TEXT|F_BPAD)))
82 					    bpad(pr);
83 				    if (cnt == 1 && pr->nospace) {
84 					savech = *pr->nospace;
85 					*pr->nospace = '\0';
86 				    }
87 				    print(pr, bp);
88 				    if (cnt == 1 && pr->nospace)
89 					*pr->nospace = savech;
90 			    }
91 		    }
92 	if (endfu) {
93 		/*
94 		 * If eaddress not set, error or file size was multiple of
95 		 * blocksize, and no partial block ever found.
96 		 */
97 		if (!eaddress) {
98 			if (!address)
99 				return;
100 			eaddress = address;
101 		}
102 		for (pr = endfu->nextpr; pr; pr = pr->nextpr)
103 			switch(pr->flags) {
104 			case F_ADDRESS:
105 				(void)printf(pr->fmt, (quad_t)eaddress);
106 				break;
107 			case F_TEXT:
108 				(void)printf("%s", pr->fmt);
109 				break;
110 			}
111 	}
112 }
113 
114 static void
115 print(PR *pr, u_char *bp)
116 {
117 	long double ldbl;
118 	   double f8;
119 	    float f4;
120 	  int16_t s2;
121 	   int8_t s8;
122 	  int32_t s4;
123 	u_int16_t u2;
124 	u_int32_t u4;
125 	u_int64_t u8;
126 
127 	switch(pr->flags) {
128 	case F_ADDRESS:
129 		(void)printf(pr->fmt, (quad_t)address);
130 		break;
131 	case F_BPAD:
132 		(void)printf(pr->fmt, "");
133 		break;
134 	case F_C:
135 		conv_c(pr, bp, eaddress ? eaddress - address :
136 		    blocksize - address % blocksize);
137 		break;
138 	case F_CHAR:
139 		(void)printf(pr->fmt, *bp);
140 		break;
141 	case F_DBL:
142 		switch(pr->bcnt) {
143 		case 4:
144 			bcopy(bp, &f4, sizeof(f4));
145 			(void)printf(pr->fmt, f4);
146 			break;
147 		case 8:
148 			bcopy(bp, &f8, sizeof(f8));
149 			(void)printf(pr->fmt, f8);
150 			break;
151 		default:
152 			if (pr->bcnt == sizeof(long double)) {
153 				bcopy(bp, &ldbl, sizeof(ldbl));
154 				(void)printf(pr->fmt, ldbl);
155 			}
156 			break;
157 		}
158 		break;
159 	case F_INT:
160 		switch(pr->bcnt) {
161 		case 1:
162 			(void)printf(pr->fmt, (quad_t)(signed char)*bp);
163 			break;
164 		case 2:
165 			bcopy(bp, &s2, sizeof(s2));
166 			(void)printf(pr->fmt, (quad_t)s2);
167 			break;
168 		case 4:
169 			bcopy(bp, &s4, sizeof(s4));
170 			(void)printf(pr->fmt, (quad_t)s4);
171 			break;
172 		case 8:
173 			bcopy(bp, &s8, sizeof(s8));
174 			(void)printf(pr->fmt, s8);
175 			break;
176 		}
177 		break;
178 	case F_P:
179 		(void)printf(pr->fmt, isprint(*bp) ? *bp : '.');
180 		break;
181 	case F_STR:
182 		(void)printf(pr->fmt, (char *)bp);
183 		break;
184 	case F_TEXT:
185 		(void)printf("%s", pr->fmt);
186 		break;
187 	case F_U:
188 		conv_u(pr, bp);
189 		break;
190 	case F_UINT:
191 		switch(pr->bcnt) {
192 		case 1:
193 			(void)printf(pr->fmt, (u_quad_t)*bp);
194 			break;
195 		case 2:
196 			bcopy(bp, &u2, sizeof(u2));
197 			(void)printf(pr->fmt, (u_quad_t)u2);
198 			break;
199 		case 4:
200 			bcopy(bp, &u4, sizeof(u4));
201 			(void)printf(pr->fmt, (u_quad_t)u4);
202 			break;
203 		case 8:
204 			bcopy(bp, &u8, sizeof(u8));
205 			(void)printf(pr->fmt, u8);
206 			break;
207 		}
208 		break;
209 	}
210 }
211 
212 void
213 bpad(PR *pr)
214 {
215 	static char const *spec = " -0+#";
216 	char *p1, *p2;
217 
218 	/*
219 	 * Remove all conversion flags; '-' is the only one valid
220 	 * with %s, and it's not useful here.
221 	 */
222 	pr->flags = F_BPAD;
223 	pr->cchar[0] = 's';
224 	pr->cchar[1] = '\0';
225 	for (p1 = pr->fmt; *p1 != '%'; ++p1);
226 	for (p2 = ++p1; *p1 && strchr(spec, *p1); ++p1);
227 	while ((*p2++ = *p1++));
228 }
229 
230 static char **_argv;
231 
232 u_char *
233 get(void)
234 {
235 	static int ateof = 1;
236 	static u_char *curp, *savp;
237 	int n;
238 	int need, nread;
239 	int valid_save = 0;
240 	u_char *tmpp;
241 
242 	if (!curp) {
243 		if ((curp = calloc(1, blocksize)) == NULL)
244 			err(1, NULL);
245 		if ((savp = calloc(1, blocksize)) == NULL)
246 			err(1, NULL);
247 	} else {
248 		tmpp = curp;
249 		curp = savp;
250 		savp = tmpp;
251 		address += blocksize;
252 		valid_save = 1;
253 	}
254 	for (need = blocksize, nread = 0;;) {
255 		/*
256 		 * if read the right number of bytes, or at EOF for one file,
257 		 * and no other files are available, zero-pad the rest of the
258 		 * block and set the end flag.
259 		 */
260 		if (!length || (ateof && !next((char **)NULL))) {
261 			if (odmode && address < skip)
262 				errx(1, "cannot skip past end of input");
263 			if (need == blocksize)
264 				return((u_char *)NULL);
265 			/*
266 			 * XXX bcmp() is not quite right in the presence
267 			 * of multibyte characters.
268 			 */
269 			if (vflag != ALL &&
270 			    valid_save &&
271 			    bcmp(curp, savp, nread) == 0) {
272 				if (vflag != DUP)
273 					(void)printf("*\n");
274 				return((u_char *)NULL);
275 			}
276 			bzero((char *)curp + nread, need);
277 			eaddress = address + nread;
278 			return(curp);
279 		}
280 		n = fread((char *)curp + nread, sizeof(u_char),
281 		    length == -1 ? need : MIN(length, need), stdin);
282 		if (!n) {
283 			if (ferror(stdin))
284 				warn("%s", _argv[-1]);
285 			ateof = 1;
286 			continue;
287 		}
288 		ateof = 0;
289 		if (length != -1)
290 			length -= n;
291 		if (!(need -= n)) {
292 			/*
293 			 * XXX bcmp() is not quite right in the presence
294 			 * of multibyte characters.
295 			 */
296 			if (vflag == ALL || vflag == FIRST ||
297 			    valid_save == 0 ||
298 			    bcmp(curp, savp, blocksize) != 0) {
299 				if (vflag == DUP || vflag == FIRST)
300 					vflag = WAIT;
301 				return(curp);
302 			}
303 			if (vflag == WAIT)
304 				(void)printf("*\n");
305 			vflag = DUP;
306 			address += blocksize;
307 			need = blocksize;
308 			nread = 0;
309 		}
310 		else
311 			nread += n;
312 	}
313 }
314 
315 size_t
316 peek(u_char *buf, size_t nbytes)
317 {
318 	size_t n, nread;
319 	int c;
320 
321 	if (length != -1 && nbytes > (unsigned int)length)
322 		nbytes = length;
323 	nread = 0;
324 	while (nread < nbytes && (c = getchar()) != EOF) {
325 		*buf++ = c;
326 		nread++;
327 	}
328 	n = nread;
329 	while (n-- > 0) {
330 		c = *--buf;
331 		ungetc(c, stdin);
332 	}
333 	return (nread);
334 }
335 
336 int
337 next(char **argv)
338 {
339 	static int done;
340 	int statok;
341 
342 	if (argv) {
343 		_argv = argv;
344 		return(1);
345 	}
346 	for (;;) {
347 		if (*_argv) {
348 			done = 1;
349 			if (!(freopen(*_argv, "r", stdin))) {
350 				warn("%s", *_argv);
351 				exitval = 1;
352 				++_argv;
353 				continue;
354 			}
355 			statok = 1;
356 		} else {
357 			if (done++)
358 				return(0);
359 			statok = 0;
360 		}
361 
362 		if (caph_limit_stream(fileno(stdin), CAPH_READ) < 0)
363 			err(1, "unable to restrict %s",
364 			    statok ? *_argv : "stdin");
365 
366 		/*
367 		 * We've opened our last input file; enter capsicum sandbox.
368 		 */
369 		if (statok == 0 || *(_argv + 1) == NULL) {
370 			if (cap_enter() < 0 && errno != ENOSYS)
371 				err(1, "unable to enter capability mode");
372 		}
373 
374 		if (skip)
375 			doskip(statok ? *_argv : "stdin", statok);
376 		if (*_argv)
377 			++_argv;
378 		if (!skip)
379 			return(1);
380 	}
381 	/* NOTREACHED */
382 }
383 
384 void
385 doskip(const char *fname, int statok)
386 {
387 	int cnt;
388 	struct stat sb;
389 
390 	if (statok) {
391 		if (fstat(fileno(stdin), &sb))
392 			err(1, "%s", fname);
393 		if (S_ISREG(sb.st_mode) && skip > sb.st_size) {
394 			address += sb.st_size;
395 			skip -= sb.st_size;
396 			return;
397 		}
398 	}
399 	if (statok && S_ISREG(sb.st_mode)) {
400 		if (fseeko(stdin, skip, SEEK_SET))
401 			err(1, "%s", fname);
402 		address += skip;
403 		skip = 0;
404 	} else {
405 		for (cnt = 0; cnt < skip; ++cnt)
406 			if (getchar() == EOF)
407 				break;
408 		address += cnt;
409 		skip -= cnt;
410 	}
411 }
412