1 3b0f3d61 2020-01-22 neels /* Commandline diff utility to test diff implementations. */
  2 3b0f3d61 2020-01-22 neels /*
  3 3b0f3d61 2020-01-22 neels  * Copyright (c) 2018 Martin Pieuchot
  4 3b0f3d61 2020-01-22 neels  * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
  5 3b0f3d61 2020-01-22 neels  *
  6 3b0f3d61 2020-01-22 neels  * Permission to use, copy, modify, and distribute this software for any
  7 3b0f3d61 2020-01-22 neels  * purpose with or without fee is hereby granted, provided that the above
  8 3b0f3d61 2020-01-22 neels  * copyright notice and this permission notice appear in all copies.
  9 3b0f3d61 2020-01-22 neels  *
 10 3b0f3d61 2020-01-22 neels  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 11 3b0f3d61 2020-01-22 neels  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 12 3b0f3d61 2020-01-22 neels  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 13 3b0f3d61 2020-01-22 neels  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 14 3b0f3d61 2020-01-22 neels  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 15 3b0f3d61 2020-01-22 neels  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 16 3b0f3d61 2020-01-22 neels  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 17 3b0f3d61 2020-01-22 neels  */
 18 3b0f3d61 2020-01-22 neels 
 19 3b0f3d61 2020-01-22 neels #include <sys/mman.h>
 20 3b0f3d61 2020-01-22 neels #include <sys/stat.h>
 21 18a9c7f8 2020-09-20 stsp #include <sys/types.h>
 22 3b0f3d61 2020-01-22 neels 
 23 3b0f3d61 2020-01-22 neels #include <err.h>
 24 3b0f3d61 2020-01-22 neels #include <fcntl.h>
 25 3b0f3d61 2020-01-22 neels #include <inttypes.h>
 26 3b0f3d61 2020-01-22 neels #include <stdio.h>
 27 3b0f3d61 2020-01-22 neels #include <stdlib.h>
 28 e10a628a 2020-09-16 stsp #include <stdbool.h>
 29 3e6cba3a 2020-08-13 stsp #include <string.h>
 30 3b0f3d61 2020-01-22 neels #include <unistd.h>
 31 3b0f3d61 2020-01-22 neels 
 32 1dfba055 2020-10-07 stsp #include <arraylist.h>
 33 1dfba055 2020-10-07 stsp #include <diff_main.h>
 34 1dfba055 2020-10-07 stsp #include <diff_output.h>
 35 8ad022d2 2020-05-05 neels 
 36 3b0f3d61 2020-01-22 neels __dead void	 usage(void);
 37 b7ba71f0 2020-10-07 stsp int		 diffreg(char *, char *, bool, bool, int, bool);
 38 7a54ad3a 2020-09-20 stsp FILE *		 openfile(const char *, char **, struct stat *);
 39 3b0f3d61 2020-01-22 neels 
 40 3b0f3d61 2020-01-22 neels __dead void
 41 3b0f3d61 2020-01-22 neels usage(void)
 42 3b0f3d61 2020-01-22 neels {
 43 760fe30e 2020-05-05 neels 	fprintf(stderr,
 44 0c9a7e9d 2020-10-07 stsp 		"usage: %s [-pwe] [-U n] file1 file2\n"
 45 760fe30e 2020-05-05 neels 		"\n"
 46 760fe30e 2020-05-05 neels 		"  -p   Use Patience Diff (slower but often nicer)\n"
 47 732e8ee0 2020-09-20 stsp 		"  -w   Ignore Whitespace\n"
 48 0c9a7e9d 2020-10-07 stsp 		"  -U n Number of Context Lines\n"
 49 0c9a7e9d 2020-10-07 stsp 		"  -e   Produce ed script output\n"
 50 760fe30e 2020-05-05 neels 		, getprogname());
 51 3b0f3d61 2020-01-22 neels 	exit(1);
 52 3b0f3d61 2020-01-22 neels }
 53 3b0f3d61 2020-01-22 neels 
 54 3b0f3d61 2020-01-22 neels int
 55 3b0f3d61 2020-01-22 neels main(int argc, char *argv[])
 56 3b0f3d61 2020-01-22 neels {
 57 3e6cba3a 2020-08-13 stsp 	int ch, rc;
 58 732e8ee0 2020-09-20 stsp 	bool do_patience = false, ignore_whitespace = false;
 59 b7ba71f0 2020-10-07 stsp 	bool edscript = false;
 60 527f2c8a 2020-09-20 stsp 	int context_lines = 3;
 61 3b0f3d61 2020-01-22 neels 
 62 0c9a7e9d 2020-10-07 stsp 	while ((ch = getopt(argc, argv, "pwU:e")) != -1) {
 63 3b0f3d61 2020-01-22 neels 		switch (ch) {
 64 760fe30e 2020-05-05 neels 		case 'p':
 65 760fe30e 2020-05-05 neels 			do_patience = true;
 66 760fe30e 2020-05-05 neels 			break;
 67 732e8ee0 2020-09-20 stsp 		case 'w':
 68 732e8ee0 2020-09-20 stsp 			ignore_whitespace = true;
 69 732e8ee0 2020-09-20 stsp 			break;
 70 0c9a7e9d 2020-10-07 stsp 		case 'U':
 71 527f2c8a 2020-09-20 stsp 			context_lines = atoi(optarg);
 72 527f2c8a 2020-09-20 stsp 			break;
 73 b7ba71f0 2020-10-07 stsp 		case 'e':
 74 b7ba71f0 2020-10-07 stsp 			edscript = true;
 75 b7ba71f0 2020-10-07 stsp 			break;
 76 3b0f3d61 2020-01-22 neels 		default:
 77 3b0f3d61 2020-01-22 neels 			usage();
 78 3b0f3d61 2020-01-22 neels 		}
 79 3b0f3d61 2020-01-22 neels 	}
 80 3b0f3d61 2020-01-22 neels 
 81 3b0f3d61 2020-01-22 neels 	argc -= optind;
 82 3b0f3d61 2020-01-22 neels 	argv += optind;
 83 3b0f3d61 2020-01-22 neels 
 84 3b0f3d61 2020-01-22 neels 	if (argc != 2)
 85 3b0f3d61 2020-01-22 neels 		usage();
 86 3b0f3d61 2020-01-22 neels 
 87 527f2c8a 2020-09-20 stsp 	rc = diffreg(argv[0], argv[1], do_patience, ignore_whitespace,
 88 b7ba71f0 2020-10-07 stsp 	    context_lines, edscript);
 89 3e6cba3a 2020-08-13 stsp 	if (rc != DIFF_RC_OK) {
 90 3e6cba3a 2020-08-13 stsp 		fprintf(stderr, "diff: %s\n", strerror(rc));
 91 3e6cba3a 2020-08-13 stsp 		return 1;
 92 3e6cba3a 2020-08-13 stsp 	}
 93 3e6cba3a 2020-08-13 stsp 	return 0;
 94 3b0f3d61 2020-01-22 neels }
 95 3b0f3d61 2020-01-22 neels 
 96 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_patience;
 97 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_myers_divide;
 98 0d27172a 2020-05-06 neels const struct diff_algo_config patience;
 99 0d27172a 2020-05-06 neels const struct diff_algo_config myers_divide;
100 3b0f3d61 2020-01-22 neels 
101 760fe30e 2020-05-05 neels const struct diff_algo_config myers_then_patience = (struct diff_algo_config){
102 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_myers,
103 9e668157 2020-01-27 neels 	.permitted_state_size = 1024 * 1024 * sizeof(int),
104 3b0f3d61 2020-01-22 neels 	.fallback_algo = &patience,
105 3b0f3d61 2020-01-22 neels };
106 3b0f3d61 2020-01-22 neels 
107 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_myers_divide =
108 0d27172a 2020-05-06 neels 	(struct diff_algo_config){
109 760fe30e 2020-05-05 neels 	.impl = diff_algo_myers,
110 760fe30e 2020-05-05 neels 	.permitted_state_size = 1024 * 1024 * sizeof(int),
111 760fe30e 2020-05-05 neels 	.fallback_algo = &myers_divide,
112 760fe30e 2020-05-05 neels };
113 760fe30e 2020-05-05 neels 
114 3b0f3d61 2020-01-22 neels const struct diff_algo_config patience = (struct diff_algo_config){
115 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_patience,
116 0d27172a 2020-05-06 neels 	/* After subdivision, do Patience again: */
117 0d27172a 2020-05-06 neels 	.inner_algo = &patience,
118 0d27172a 2020-05-06 neels 	/* If subdivision failed, do Myers Divide et Impera: */
119 0d27172a 2020-05-06 neels 	.fallback_algo = &myers_then_myers_divide,
120 3b0f3d61 2020-01-22 neels };
121 3b0f3d61 2020-01-22 neels 
122 3b0f3d61 2020-01-22 neels const struct diff_algo_config myers_divide = (struct diff_algo_config){
123 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_myers_divide,
124 0d27172a 2020-05-06 neels 	/* When division succeeded, start from the top: */
125 0d27172a 2020-05-06 neels 	.inner_algo = &myers_then_myers_divide,
126 0d27172a 2020-05-06 neels 	/* (fallback_algo = NULL implies diff_algo_none). */
127 3b0f3d61 2020-01-22 neels };
128 3b0f3d61 2020-01-22 neels 
129 3b0f3d61 2020-01-22 neels const struct diff_config diff_config = {
130 3b0f3d61 2020-01-22 neels 	.atomize_func = diff_atomize_text_by_line,
131 760fe30e 2020-05-05 neels 	.algo = &myers_then_myers_divide,
132 3b0f3d61 2020-01-22 neels };
133 3b0f3d61 2020-01-22 neels 
134 760fe30e 2020-05-05 neels const struct diff_config diff_config_patience = {
135 760fe30e 2020-05-05 neels 	.atomize_func = diff_atomize_text_by_line,
136 760fe30e 2020-05-05 neels 	.algo = &myers_then_patience,
137 760fe30e 2020-05-05 neels };
138 760fe30e 2020-05-05 neels 
139 3b0f3d61 2020-01-22 neels int
140 527f2c8a 2020-09-20 stsp diffreg(char *file1, char *file2, bool do_patience, bool ignore_whitespace,
141 b7ba71f0 2020-10-07 stsp     int context_lines, bool edscript)
142 3b0f3d61 2020-01-22 neels {
143 3b0f3d61 2020-01-22 neels 	char *str1, *str2;
144 7a54ad3a 2020-09-20 stsp 	FILE *f1, *f2;
145 3b0f3d61 2020-01-22 neels 	struct stat st1, st2;
146 3b0f3d61 2020-01-22 neels 	struct diff_input_info info = {
147 3b0f3d61 2020-01-22 neels 		.left_path = file1,
148 3b0f3d61 2020-01-22 neels 		.right_path = file2,
149 3b0f3d61 2020-01-22 neels 	};
150 f8cbb8fe 2020-05-05 neels 	struct diff_result *result;
151 3e6cba3a 2020-08-13 stsp 	int rc;
152 0d27172a 2020-05-06 neels 	const struct diff_config *cfg;
153 00d5652b 2020-09-22 stsp 	int diff_flags = 0;
154 0d27172a 2020-05-06 neels 	
155 0d27172a 2020-05-06 neels 	cfg = do_patience ? &diff_config_patience : &diff_config;
156 3b0f3d61 2020-01-22 neels 
157 7a54ad3a 2020-09-20 stsp 	f1 = openfile(file1, &str1, &st1);
158 7a54ad3a 2020-09-20 stsp 	f2 = openfile(file2, &str2, &st2);
159 3b0f3d61 2020-01-22 neels 
160 00d5652b 2020-09-22 stsp 	if (ignore_whitespace)
161 00d5652b 2020-09-22 stsp 		diff_flags |= DIFF_FLAG_IGNORE_WHITESPACE;
162 00d5652b 2020-09-22 stsp 
163 7a54ad3a 2020-09-20 stsp 	result = diff_main(cfg, f1, str1, st1.st_size, f2, str2, st2.st_size,
164 00d5652b 2020-09-22 stsp 	    diff_flags);
165 f8cbb8fe 2020-05-05 neels #if 0
166 f8cbb8fe 2020-05-05 neels 	rc = diff_output_plain(stdout, &info, result);
167 f8cbb8fe 2020-05-05 neels #else
168 b7ba71f0 2020-10-07 stsp 	if (edscript)
169 b7ba71f0 2020-10-07 stsp 		rc = diff_output_edscript(NULL, stdout, &info, result);
170 b7ba71f0 2020-10-07 stsp 	else {
171 b7ba71f0 2020-10-07 stsp 		rc = diff_output_unidiff(NULL, stdout, &info, result,
172 b7ba71f0 2020-10-07 stsp 		    context_lines);
173 b7ba71f0 2020-10-07 stsp 	}
174 f8cbb8fe 2020-05-05 neels #endif
175 f8cbb8fe 2020-05-05 neels 	diff_result_free(result);
176 3b0f3d61 2020-01-22 neels 
177 c6eecea3 2020-07-26 stsp 	if (str1)
178 c6eecea3 2020-07-26 stsp 		munmap(str1, st1.st_size);
179 c6eecea3 2020-07-26 stsp 	if (str2)
180 c6eecea3 2020-07-26 stsp 		munmap(str2, st2.st_size);
181 7a54ad3a 2020-09-20 stsp 	fclose(f1);
182 7a54ad3a 2020-09-20 stsp 	fclose(f2);
183 3b0f3d61 2020-01-22 neels 
184 f8cbb8fe 2020-05-05 neels 	return rc;
185 3b0f3d61 2020-01-22 neels }
186 3b0f3d61 2020-01-22 neels 
187 7a54ad3a 2020-09-20 stsp FILE *
188 c6eecea3 2020-07-26 stsp openfile(const char *path, char **p, struct stat *st)
189 3b0f3d61 2020-01-22 neels {
190 7a54ad3a 2020-09-20 stsp 	FILE *f = NULL;
191 3b0f3d61 2020-01-22 neels 
192 7a54ad3a 2020-09-20 stsp 	f = fopen(path, "r");
193 7a54ad3a 2020-09-20 stsp 	if (f == NULL)
194 3b0f3d61 2020-01-22 neels 		err(2, "%s", path);
195 3b0f3d61 2020-01-22 neels 
196 7a54ad3a 2020-09-20 stsp 	if (fstat(fileno(f), st) == -1)
197 3b0f3d61 2020-01-22 neels 		err(2, "%s", path);
198 3b0f3d61 2020-01-22 neels 
199 c6eecea3 2020-07-26 stsp #ifndef DIFF_NO_MMAP
200 7a54ad3a 2020-09-20 stsp 	*p = mmap(NULL, st->st_size, PROT_READ, MAP_PRIVATE, fileno(f), 0);
201 c6eecea3 2020-07-26 stsp 	if (*p == MAP_FAILED)
202 c6eecea3 2020-07-26 stsp #endif
203 c6eecea3 2020-07-26 stsp 		*p = NULL; /* fall back on file I/O */
204 3b0f3d61 2020-01-22 neels 
205 7a54ad3a 2020-09-20 stsp 	return f;
206 3b0f3d61 2020-01-22 neels }