xref: /netbsd/usr.bin/hexdump/display.c (revision bb0373ec)
1 /*	$NetBSD: display.c,v 1.25 2016/03/04 03:02:52 dholland Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 #if !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)display.c	8.1 (Berkeley) 6/6/93";
40 #else
41 __RCSID("$NetBSD: display.c,v 1.25 2016/03/04 03:02:52 dholland Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 
48 #include <ctype.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <inttypes.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <util.h>
57 
58 #include "hexdump.h"
59 
60 enum _vflag vflag = FIRST;
61 
62 static off_t address;			/* address/offset in stream */
63 static off_t eaddress;			/* end address */
64 
65 static u_char *get(void);
66 static inline void print(PR *, u_char *);
67 
68 void
display(void)69 display(void)
70 {
71 	FS *fs;
72 	FU *fu;
73 	PR *pr;
74 	int cnt;
75 	u_char *bp;
76 	off_t saveaddress;
77 	u_char savech, *savebp;
78 
79 	savech = 0;
80 	while ((bp = get()) != NULL)
81 	    for (fs = fshead, savebp = bp, saveaddress = address; fs;
82 		fs = fs->nextfs, bp = savebp, address = saveaddress)
83 		    for (fu = fs->nextfu; fu; fu = fu->nextfu) {
84 			if (fu->flags&F_IGNORE)
85 				break;
86 			for (cnt = fu->reps; cnt; --cnt)
87 			    for (pr = fu->nextpr; pr; address += pr->bcnt,
88 				bp += pr->bcnt, pr = pr->nextpr) {
89 				    if (eaddress && address >= eaddress &&
90 					!(pr->flags & (F_TEXT|F_BPAD)))
91 					    bpad(pr);
92 				    if (cnt == 1 && pr->nospace) {
93 					savech = *pr->nospace;
94 					*pr->nospace = '\0';
95 				    }
96 				    print(pr, bp);
97 				    if (cnt == 1 && pr->nospace)
98 					*pr->nospace = savech;
99 			    }
100 		    }
101 	if (endfu) {
102 		/*
103 		 * If eaddress not set, error or file size was multiple of
104 		 * blocksize, and no partial block ever found.
105 		 */
106 		if (!eaddress) {
107 			if (!address)
108 				return;
109 			eaddress = address;
110 		}
111 		for (pr = endfu->nextpr; pr; pr = pr->nextpr)
112 			switch(pr->flags) {
113 			case F_ADDRESS:
114 				(void)printf(pr->fmt, (int64_t)eaddress);
115 				break;
116 			case F_TEXT:
117 				(void)printf("%s", pr->fmt);
118 				break;
119 			}
120 	}
121 }
122 
123 static inline void
print(PR * pr,u_char * bp)124 print(PR *pr, u_char *bp)
125 {
126 	   double f8;
127 	    float f4;
128 	  int16_t s2;
129 	  int32_t s4;
130 	  int64_t s8;
131 	 uint16_t u2;
132 	 uint32_t u4;
133 	 uint64_t u8;
134 
135 	switch(pr->flags) {
136 	case F_ADDRESS:
137 		(void)printf(pr->fmt, (int64_t)address);
138 		break;
139 	case F_BPAD:
140 		(void)printf(pr->fmt, "");
141 		break;
142 	case F_C:
143 		conv_c(pr, bp);
144 		break;
145 	case F_CHAR:
146 		(void)printf(pr->fmt, *bp);
147 		break;
148 	case F_DBL:
149 		switch(pr->bcnt) {
150 		case 4:
151 			memmove(&f4, bp, sizeof(f4));
152 			(void)printf(pr->fmt, f4);
153 			break;
154 		case 8:
155 			memmove(&f8, bp, sizeof(f8));
156 			(void)printf(pr->fmt, f8);
157 			break;
158 		}
159 		break;
160 	case F_INT:
161 		switch(pr->bcnt) {
162 		case 1:
163 			(void)printf(pr->fmt, (int64_t)*bp);
164 			break;
165 		case 2:
166 			memmove(&s2, bp, sizeof(s2));
167 			(void)printf(pr->fmt, (int64_t)s2);
168 			break;
169 		case 4:
170 			memmove(&s4, bp, sizeof(s4));
171 			(void)printf(pr->fmt, (int64_t)s4);
172 			break;
173 		case 8:
174 			memmove(&s8, bp, sizeof(s8));
175 			(void)printf(pr->fmt, (int64_t)s8);
176 			break;
177 		}
178 		break;
179 	case F_P:
180 		(void)printf(pr->fmt, isprint(*bp) ? *bp : '.');
181 		break;
182 	case F_STR:
183 		(void)printf(pr->fmt, (char *)bp);
184 		break;
185 	case F_TEXT:
186 		(void)printf("%s", pr->fmt);
187 		break;
188 	case F_U:
189 		conv_u(pr, bp);
190 		break;
191 	case F_UINT:
192 		switch(pr->bcnt) {
193 		case 1:
194 			(void)printf(pr->fmt, (uint64_t)*bp);
195 			break;
196 		case 2:
197 			memmove(&u2, bp, sizeof(u2));
198 			(void)printf(pr->fmt, (uint64_t)u2);
199 			break;
200 		case 4:
201 			memmove(&u4, bp, sizeof(u4));
202 			(void)printf(pr->fmt, (uint64_t)u4);
203 			break;
204 		case 8:
205 			memmove(&u8, bp, sizeof(u8));
206 			(void)printf(pr->fmt, (uint64_t)u8);
207 			break;
208 		}
209 		break;
210 	}
211 }
212 
213 void
bpad(PR * pr)214 bpad(PR *pr)
215 {
216 	static const char *spec = " -0+#";
217 	char *p1, *p2;
218 
219 	/*
220 	 * Remove all conversion flags; '-' is the only one valid
221 	 * with %s, and it's not useful here.
222 	 */
223 	pr->flags = F_BPAD;
224 	pr->cchar[0] = 's';
225 	pr->cchar[1] = '\0';
226 	for (p1 = pr->fmt; *p1 != '%'; ++p1);
227 	for (p2 = ++p1; *p1 && strchr(spec, *p1); ++p1);
228 	while ((*p2++ = *p1++) != '\0');
229 }
230 
231 static char **_argv;
232 
233 static u_char *
get(void)234 get(void)
235 {
236 	static int ateof = 1;
237 	static u_char *curp, *savp;
238 	int n;
239 	int need, nread;
240 	u_char *tmpp;
241 
242 	if (!curp) {
243 		curp = ecalloc(blocksize, 1);
244 		savp = ecalloc(blocksize, 1);
245 	} else {
246 		tmpp = curp;
247 		curp = savp;
248 		savp = tmpp;
249 		address += blocksize;
250 	}
251 	for (need = blocksize, nread = 0;;) {
252 		/*
253 		 * if read the right number of bytes, or at EOF for one file,
254 		 * and no other files are available, zero-pad the rest of the
255 		 * block and set the end flag.
256 		 */
257 		if (!length || (ateof && !next())) {
258 			if (need == blocksize)
259 				return(NULL);
260 			if (!need && vflag != ALL &&
261 			    !memcmp(curp, savp, nread)) {
262 				if (vflag != DUP)
263 					(void)printf("*\n");
264 				return(NULL);
265 			}
266 			memset((char *)curp + nread, 0, need);
267 			eaddress = address + nread;
268 			return(curp);
269 		}
270 		n = fread((char *)curp + nread, sizeof(u_char),
271 		    length == -1 ? need : MIN(length, need), stdin);
272 		if (!n) {
273 			if (ferror(stdin))
274 				warn("%s", _argv[-1]);
275 			ateof = 1;
276 			continue;
277 		}
278 		ateof = 0;
279 		if (length != -1)
280 			length -= n;
281 		if (!(need -= n)) {
282 			if (vflag == ALL || vflag == FIRST ||
283 			    memcmp(curp, savp, blocksize)) {
284 				if (vflag == DUP || vflag == FIRST)
285 					vflag = WAIT;
286 				return(curp);
287 			}
288 			if (vflag == WAIT)
289 				(void)printf("*\n");
290 			vflag = DUP;
291 			address += blocksize;
292 			need = blocksize;
293 			nread = 0;
294 		}
295 		else
296 			nread += n;
297 	}
298 }
299 
300 /*
301  * Save argv for later retrieval.
302  */
303 void
stashargv(char ** argv)304 stashargv(char **argv)
305 {
306 	_argv = argv;
307 }
308 
309 /*
310  * Get the next file. The idea with the twisty logic seems to be to
311  * either read N filenames from argv and then exit, or if there aren't
312  * any, to use stdin and then exit. It should probably be simplified.
313  * The "done" flag doesn't mean "we are done", it means "we are done
314  * once we run out of filenames".
315  *
316  * XXX: is there any reason not to remove the logic that inhibits
317  * calling fstat if using stdin and not a filename? It should be safe
318  * to call fstat on any fd.
319  *
320  * Note: I have ruled that if there is one file on the command line
321  * and it doesn't open, we should exit after complaining about it and
322  * not then proceed to read stdin; the latter seems like unexpected
323  * and undesirable behavior. Also, it didn't work anyway, because the
324  * freopen call clobbers stdin while failing. -- dholland 20160303
325  */
326 int
next(void)327 next(void)
328 {
329 	static int done;
330 	int statok;
331 
332 	for (;;) {
333 		if (*_argv) {
334 			done = 1;
335 			if (!(freopen(*_argv, "r", stdin))) {
336 				warn("%s", *_argv);
337 				exitval = 1;
338 				++_argv;
339 				continue;
340 			}
341 			statok = 1;
342 		} else {
343 			if (done++)
344 				return(0);
345 			statok = 0;
346 		}
347 		if (skip)
348 			doskip(statok ? *_argv : "stdin", statok);
349 		if (*_argv)
350 			++_argv;
351 		if (!skip)
352 			return(1);
353 	}
354 	/* NOTREACHED */
355 }
356 
357 void
doskip(const char * fname,int statok)358 doskip(const char *fname, int statok)
359 {
360 	int cnt;
361 	struct stat sb;
362 
363 	if (statok) {
364 		if (fstat(fileno(stdin), &sb))
365 			err(1, "fstat %s", fname);
366 		if (S_ISREG(sb.st_mode) && skip >= sb.st_size) {
367 			address += sb.st_size;
368 			skip -= sb.st_size;
369 			return;
370 		}
371 	} else
372 		sb.st_mode = S_IFIFO;
373 
374 	if (S_ISREG(sb.st_mode)) {
375 		if (fseek(stdin, skip, SEEK_SET))
376 			err(1, "fseek %s", fname);
377 		address += skip;
378 		skip = 0;
379 	} else {
380 		for (cnt = 0; cnt < skip; ++cnt)
381 			if (getchar() == EOF)
382 				break;
383 		address += cnt;
384 		skip -= cnt;
385 	}
386 }
387