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