1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23 /*
24 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
25 * Use is subject to license terms.
26 */
27
28 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
29 /* All Rights Reserved */
30
31 #pragma ident "%Z%%M% %I% %E% SMI"
32
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <unistd.h>
36 #include <ctype.h>
37 #include <locale.h>
38 #include <sys/types.h>
39 #include <sys/stat.h>
40 #include <limits.h>
41 #include <stdarg.h>
42
43 #define C 3
44 #define RANGE 30
45 #define LEN 255
46 #define INF 16384
47
48 char *text[2][RANGE];
49 long lineno[2] = {1, 1}; /* no. of 1st stored line in each file */
50 int ntext[2]; /* number of stored lines in each */
51 long n0, n1; /* scan pointer in each */
52 int bflag;
53 int debug = 0;
54 FILE *file[2];
55 static int diffFound = 0;
56
57 static char *getl(int f, long n);
58 static void clrl(int f, long n);
59 static void movstr(char *s, char *t);
60 static int easysynch(void);
61 static int output(int a, int b);
62 static void change(long a, int b, long c, int d, char *s);
63 static void range(long a, int b);
64 static int cmp(char *s, char *t);
65 static FILE *dopen(char *f1, char *f2);
66 static void progerr(char *s);
67 static void error(char *err, ...);
68 static int hardsynch(void);
69
70 /* return pointer to line n of file f */
71 static char *
getl(int f,long n)72 getl(int f, long n)
73 {
74 char *t;
75 int delta, nt;
76
77 again:
78 delta = n - lineno[f];
79 nt = ntext[f];
80 if (delta < 0)
81 progerr("1");
82 if (delta < nt)
83 return (text[f][delta]);
84 if (delta > nt)
85 progerr("2");
86 if (nt >= RANGE)
87 progerr("3");
88 if (feof(file[f]))
89 return (NULL);
90 t = text[f][nt];
91 if (t == 0) {
92 t = text[f][nt] = (char *)malloc(LEN+1);
93 if (t == NULL)
94 if (hardsynch())
95 goto again;
96 else
97 progerr("5");
98 }
99 t = fgets(t, LEN, file[f]);
100 if (t != NULL)
101 ntext[f]++;
102 return (t);
103 }
104
105 /* remove thru line n of file f from storage */
106 static void
clrl(int f,long n)107 clrl(int f, long n)
108 {
109 int i, j;
110
111 j = n-lineno[f]+1;
112 for (i = 0; i+j < ntext[f]; i++)
113 movstr(text[f][i+j], text[f][i]);
114 lineno[f] = n+1;
115 ntext[f] -= j;
116 }
117
118 static void
movstr(char * s,char * t)119 movstr(char *s, char *t)
120 {
121 while (*t++ = *s++)
122 continue;
123 }
124
125 int
main(int argc,char ** argv)126 main(int argc, char **argv)
127 {
128 char *s0, *s1;
129
130 if ((argc > 1) && (*argv[1] == '-')) {
131 argc--;
132 argv++;
133 while (*++argv[0])
134 if (*argv[0] == 'b')
135 bflag++;
136 }
137
138 (void) setlocale(LC_ALL, "");
139 #if !defined(TEXT_DOMAIN) /* Should be defined by cc -D */
140 #define TEXT_DOMAIN "SYS_TEST" /* Use this only if it weren't */
141 #endif
142 (void) textdomain(TEXT_DOMAIN);
143
144 if (argc != 3)
145 error(gettext("must have 2 file arguments"));
146 file[0] = dopen(argv[1], argv[2]);
147 file[1] = dopen(argv[2], argv[1]);
148 for (;;) {
149 s0 = getl(0, ++n0);
150 s1 = getl(1, ++n1);
151 if (s0 == NULL || s1 == NULL)
152 break;
153 if (cmp(s0, s1) != 0) {
154 if (!easysynch() && !hardsynch())
155 progerr("5");
156 } else {
157 clrl(0, n0);
158 clrl(1, n1);
159 }
160 }
161 /* diff is expected to return 1 if the files differ */
162 if (s0 == NULL && s1 == NULL)
163 return (diffFound);
164 if (s0 == NULL) {
165 (void) output(-1, INF);
166 return (1);
167 }
168 if (s1 == NULL) {
169 (void) output(INF, -1);
170 return (1);
171 }
172 /* NOTREACHED */
173 return (0);
174 }
175
176 /* synch on C successive matches */
177 static int
easysynch()178 easysynch()
179 {
180 int i, j;
181 int k, m;
182 char *s0, *s1;
183
184 for (i = j = 1; i < RANGE && j < RANGE; i++, j++) {
185 s0 = getl(0, n0+i);
186 if (s0 == NULL)
187 return (output(INF, INF));
188 for (k = C-1; k < j; k++) {
189 for (m = 0; m < C; m++)
190 if (cmp(getl(0, n0+i-m),
191 getl(1, n1+k-m)) != 0)
192 goto cont1;
193 return (output(i-C, k-C));
194 cont1:
195 ;
196 }
197 s1 = getl(1, n1+j);
198 if (s1 == NULL)
199 return (output(INF, INF));
200 for (k = C-1; k <= i; k++) {
201 for (m = 0; m < C; m++)
202 if (cmp(getl(0, n0+k-m),
203 getl(1, n1+j-m)) != 0)
204 goto cont2;
205 return (output(k-C, j-C));
206 cont2:
207 ;
208 }
209 }
210 return (0);
211 }
212
213 static int
output(int a,int b)214 output(int a, int b)
215 {
216 int i;
217 char *s;
218
219 if (a < 0)
220 change(n0-1, 0, n1, b, "a");
221 else if (b < 0)
222 change(n0, a, n1-1, 0, "d");
223 else
224 change(n0, a, n1, b, "c");
225 for (i = 0; i <= a; i++) {
226 s = getl(0, n0+i);
227 if (s == NULL)
228 break;
229 (void) printf("< %s", s);
230 clrl(0, n0+i);
231 }
232 n0 += i-1;
233 if (a >= 0 && b >= 0)
234 (void) printf("---\n");
235 for (i = 0; i <= b; i++) {
236 s = getl(1, n1+i);
237 if (s == NULL)
238 break;
239 (void) printf("> %s", s);
240 clrl(1, n1+i);
241 }
242 diffFound = 1;
243 n1 += i-1;
244 return (1);
245 }
246
247 static void
change(long a,int b,long c,int d,char * s)248 change(long a, int b, long c, int d, char *s)
249 {
250 range(a, b);
251 (void) printf("%s", s);
252 range(c, d);
253 (void) printf("\n");
254 }
255
256 static void
range(long a,int b)257 range(long a, int b)
258 {
259 if (b == INF)
260 (void) printf("%ld,$", a);
261 else if (b == 0)
262 (void) printf("%ld", a);
263 else
264 (void) printf("%ld,%ld", a, a+b);
265 }
266
267 static int
cmp(char * s,char * t)268 cmp(char *s, char *t)
269 {
270 if (debug)
271 (void) printf("%s:%s\n", s, t);
272 for (;;) {
273 if (bflag && isspace(*s) && isspace(*t)) {
274 while (isspace(*++s))
275 ;
276 while (isspace(*++t))
277 ;
278 }
279 if (*s != *t || *s == 0)
280 break;
281 s++;
282 t++;
283 }
284 return (*s-*t);
285 }
286
287 static FILE *
dopen(char * f1,char * f2)288 dopen(char *f1, char *f2)
289 {
290 FILE *f;
291 char b[PATH_MAX], *bptr, *eptr;
292 struct stat statbuf;
293
294 if (cmp(f1, "-") == 0) {
295 if (cmp(f2, "-") == 0)
296 error(gettext("can't do - -"));
297 else {
298 if (fstat(fileno(stdin), &statbuf) == -1)
299 error(gettext("can't access stdin"));
300 else
301 return (stdin);
302 }
303 }
304 if (stat(f1, &statbuf) == -1)
305 error(gettext("can't access %s"), f1);
306 if ((statbuf.st_mode & S_IFMT) == S_IFDIR) {
307 for (bptr = b; *bptr = *f1++; bptr++)
308 ;
309 *bptr++ = '/';
310 for (eptr = f2; *eptr; eptr++)
311 if (*eptr == '/' && eptr[1] != 0 && eptr[1] != '/')
312 f2 = eptr+1;
313 while (*bptr++ = *f2++)
314 ;
315 f1 = b;
316 }
317 f = fopen(f1, "r");
318 if (f == NULL)
319 error(gettext("can't open %s"), f1);
320 return (f);
321 }
322
323
324 static void
progerr(char * s)325 progerr(char *s)
326 {
327 error(gettext("program error %s"), s);
328 }
329
330 static void
error(char * err,...)331 error(char *err, ...)
332 {
333 va_list ap;
334
335 va_start(ap, err);
336 (void) fprintf(stderr, "diffh: ");
337 (void) vfprintf(stderr, err, ap);
338 (void) fprintf(stderr, "\n");
339 va_end(ap);
340 exit(2);
341 }
342
343 /* stub for resychronization beyond limits of text buf */
344 static int
hardsynch()345 hardsynch()
346 {
347 change(n0, INF, n1, INF, "c");
348 (void) printf(gettext("---change record omitted\n"));
349 error(gettext("can't resynchronize"));
350 return (0);
351 }
352