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 e10a628a 2020-09-16 stsp #include <diff/arraylist.h>
 33 8ad022d2 2020-05-05 neels #include <diff/diff_main.h>
 34 8ad022d2 2020-05-05 neels #include <diff/diff_output.h>
 35 8ad022d2 2020-05-05 neels 
 36 3b0f3d61 2020-01-22 neels __dead void	 usage(void);
 37 527f2c8a 2020-09-20 stsp int		 diffreg(char *, char *, bool, bool, int);
 38 c6eecea3 2020-07-26 stsp int		 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 527f2c8a 2020-09-20 stsp 		"usage: %s [-pw] [-C 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 527f2c8a 2020-09-20 stsp 		"  -C n Number of Context Lines\n"
 49 760fe30e 2020-05-05 neels 		, getprogname());
 50 3b0f3d61 2020-01-22 neels 	exit(1);
 51 3b0f3d61 2020-01-22 neels }
 52 3b0f3d61 2020-01-22 neels 
 53 3b0f3d61 2020-01-22 neels int
 54 3b0f3d61 2020-01-22 neels main(int argc, char *argv[])
 55 3b0f3d61 2020-01-22 neels {
 56 3e6cba3a 2020-08-13 stsp 	int ch, rc;
 57 732e8ee0 2020-09-20 stsp 	bool do_patience = false, ignore_whitespace = false;
 58 527f2c8a 2020-09-20 stsp 	int context_lines = 3;
 59 3b0f3d61 2020-01-22 neels 
 60 527f2c8a 2020-09-20 stsp 	while ((ch = getopt(argc, argv, "pwC:")) != -1) {
 61 3b0f3d61 2020-01-22 neels 		switch (ch) {
 62 760fe30e 2020-05-05 neels 		case 'p':
 63 760fe30e 2020-05-05 neels 			do_patience = true;
 64 760fe30e 2020-05-05 neels 			break;
 65 732e8ee0 2020-09-20 stsp 		case 'w':
 66 732e8ee0 2020-09-20 stsp 			ignore_whitespace = true;
 67 732e8ee0 2020-09-20 stsp 			break;
 68 527f2c8a 2020-09-20 stsp 		case 'C':
 69 527f2c8a 2020-09-20 stsp 			context_lines = atoi(optarg);
 70 527f2c8a 2020-09-20 stsp 			break;
 71 3b0f3d61 2020-01-22 neels 		default:
 72 3b0f3d61 2020-01-22 neels 			usage();
 73 3b0f3d61 2020-01-22 neels 		}
 74 3b0f3d61 2020-01-22 neels 	}
 75 3b0f3d61 2020-01-22 neels 
 76 3b0f3d61 2020-01-22 neels 	argc -= optind;
 77 3b0f3d61 2020-01-22 neels 	argv += optind;
 78 3b0f3d61 2020-01-22 neels 
 79 3b0f3d61 2020-01-22 neels 	if (argc != 2)
 80 3b0f3d61 2020-01-22 neels 		usage();
 81 3b0f3d61 2020-01-22 neels 
 82 527f2c8a 2020-09-20 stsp 	rc = diffreg(argv[0], argv[1], do_patience, ignore_whitespace,
 83 527f2c8a 2020-09-20 stsp 	    context_lines);
 84 3e6cba3a 2020-08-13 stsp 	if (rc != DIFF_RC_OK) {
 85 3e6cba3a 2020-08-13 stsp 		fprintf(stderr, "diff: %s\n", strerror(rc));
 86 3e6cba3a 2020-08-13 stsp 		return 1;
 87 3e6cba3a 2020-08-13 stsp 	}
 88 3e6cba3a 2020-08-13 stsp 	return 0;
 89 3b0f3d61 2020-01-22 neels }
 90 3b0f3d61 2020-01-22 neels 
 91 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_patience;
 92 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_myers_divide;
 93 0d27172a 2020-05-06 neels const struct diff_algo_config patience;
 94 0d27172a 2020-05-06 neels const struct diff_algo_config myers_divide;
 95 3b0f3d61 2020-01-22 neels 
 96 760fe30e 2020-05-05 neels const struct diff_algo_config myers_then_patience = (struct diff_algo_config){
 97 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_myers,
 98 9e668157 2020-01-27 neels 	.permitted_state_size = 1024 * 1024 * sizeof(int),
 99 3b0f3d61 2020-01-22 neels 	.fallback_algo = &patience,
100 3b0f3d61 2020-01-22 neels };
101 3b0f3d61 2020-01-22 neels 
102 0d27172a 2020-05-06 neels const struct diff_algo_config myers_then_myers_divide =
103 0d27172a 2020-05-06 neels 	(struct diff_algo_config){
104 760fe30e 2020-05-05 neels 	.impl = diff_algo_myers,
105 760fe30e 2020-05-05 neels 	.permitted_state_size = 1024 * 1024 * sizeof(int),
106 760fe30e 2020-05-05 neels 	.fallback_algo = &myers_divide,
107 760fe30e 2020-05-05 neels };
108 760fe30e 2020-05-05 neels 
109 3b0f3d61 2020-01-22 neels const struct diff_algo_config patience = (struct diff_algo_config){
110 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_patience,
111 0d27172a 2020-05-06 neels 	/* After subdivision, do Patience again: */
112 0d27172a 2020-05-06 neels 	.inner_algo = &patience,
113 0d27172a 2020-05-06 neels 	/* If subdivision failed, do Myers Divide et Impera: */
114 0d27172a 2020-05-06 neels 	.fallback_algo = &myers_then_myers_divide,
115 3b0f3d61 2020-01-22 neels };
116 3b0f3d61 2020-01-22 neels 
117 3b0f3d61 2020-01-22 neels const struct diff_algo_config myers_divide = (struct diff_algo_config){
118 3b0f3d61 2020-01-22 neels 	.impl = diff_algo_myers_divide,
119 0d27172a 2020-05-06 neels 	/* When division succeeded, start from the top: */
120 0d27172a 2020-05-06 neels 	.inner_algo = &myers_then_myers_divide,
121 0d27172a 2020-05-06 neels 	/* (fallback_algo = NULL implies diff_algo_none). */
122 3b0f3d61 2020-01-22 neels };
123 3b0f3d61 2020-01-22 neels 
124 3b0f3d61 2020-01-22 neels const struct diff_config diff_config = {
125 3b0f3d61 2020-01-22 neels 	.atomize_func = diff_atomize_text_by_line,
126 760fe30e 2020-05-05 neels 	.algo = &myers_then_myers_divide,
127 3b0f3d61 2020-01-22 neels };
128 3b0f3d61 2020-01-22 neels 
129 760fe30e 2020-05-05 neels const struct diff_config diff_config_patience = {
130 760fe30e 2020-05-05 neels 	.atomize_func = diff_atomize_text_by_line,
131 760fe30e 2020-05-05 neels 	.algo = &myers_then_patience,
132 760fe30e 2020-05-05 neels };
133 760fe30e 2020-05-05 neels 
134 3b0f3d61 2020-01-22 neels int
135 527f2c8a 2020-09-20 stsp diffreg(char *file1, char *file2, bool do_patience, bool ignore_whitespace,
136 527f2c8a 2020-09-20 stsp     int context_lines)
137 3b0f3d61 2020-01-22 neels {
138 3b0f3d61 2020-01-22 neels 	char *str1, *str2;
139 c6eecea3 2020-07-26 stsp 	int fd1, fd2;
140 3b0f3d61 2020-01-22 neels 	struct stat st1, st2;
141 3b0f3d61 2020-01-22 neels 	struct diff_input_info info = {
142 3b0f3d61 2020-01-22 neels 		.left_path = file1,
143 3b0f3d61 2020-01-22 neels 		.right_path = file2,
144 3b0f3d61 2020-01-22 neels 	};
145 f8cbb8fe 2020-05-05 neels 	struct diff_result *result;
146 3e6cba3a 2020-08-13 stsp 	int rc;
147 0d27172a 2020-05-06 neels 	const struct diff_config *cfg;
148 0d27172a 2020-05-06 neels 	
149 0d27172a 2020-05-06 neels 	cfg = do_patience ? &diff_config_patience : &diff_config;
150 3b0f3d61 2020-01-22 neels 
151 c6eecea3 2020-07-26 stsp 	fd1 = openfile(file1, &str1, &st1);
152 c6eecea3 2020-07-26 stsp 	fd2 = openfile(file2, &str2, &st2);
153 3b0f3d61 2020-01-22 neels 
154 732e8ee0 2020-09-20 stsp 	result = diff_main(cfg, fd1, str1, st1.st_size, fd2, str2, st2.st_size,
155 732e8ee0 2020-09-20 stsp 	    ignore_whitespace);
156 f8cbb8fe 2020-05-05 neels #if 0
157 f8cbb8fe 2020-05-05 neels 	rc = diff_output_plain(stdout, &info, result);
158 f8cbb8fe 2020-05-05 neels #else
159 527f2c8a 2020-09-20 stsp 	rc = diff_output_unidiff(stdout, &info, result, context_lines);
160 f8cbb8fe 2020-05-05 neels #endif
161 f8cbb8fe 2020-05-05 neels 	diff_result_free(result);
162 3b0f3d61 2020-01-22 neels 
163 c6eecea3 2020-07-26 stsp 	if (str1)
164 c6eecea3 2020-07-26 stsp 		munmap(str1, st1.st_size);
165 c6eecea3 2020-07-26 stsp 	if (str2)
166 c6eecea3 2020-07-26 stsp 		munmap(str2, st2.st_size);
167 c6eecea3 2020-07-26 stsp 	close(fd1);
168 c6eecea3 2020-07-26 stsp 	close(fd2);
169 3b0f3d61 2020-01-22 neels 
170 f8cbb8fe 2020-05-05 neels 	return rc;
171 3b0f3d61 2020-01-22 neels }
172 3b0f3d61 2020-01-22 neels 
173 c6eecea3 2020-07-26 stsp int
174 c6eecea3 2020-07-26 stsp openfile(const char *path, char **p, struct stat *st)
175 3b0f3d61 2020-01-22 neels {
176 3b0f3d61 2020-01-22 neels 	int			 fd;
177 3b0f3d61 2020-01-22 neels 
178 3b0f3d61 2020-01-22 neels 	fd = open(path, O_RDONLY);
179 3b0f3d61 2020-01-22 neels 	if (fd == -1)
180 3b0f3d61 2020-01-22 neels 		err(2, "%s", path);
181 3b0f3d61 2020-01-22 neels 
182 3b0f3d61 2020-01-22 neels 	if (fstat(fd, st) == -1)
183 3b0f3d61 2020-01-22 neels 		err(2, "%s", path);
184 3b0f3d61 2020-01-22 neels 
185 c6eecea3 2020-07-26 stsp #ifndef DIFF_NO_MMAP
186 c6eecea3 2020-07-26 stsp 	*p = mmap(NULL, st->st_size, PROT_READ, MAP_PRIVATE, fd, 0);
187 c6eecea3 2020-07-26 stsp 	if (*p == MAP_FAILED)
188 c6eecea3 2020-07-26 stsp #endif
189 c6eecea3 2020-07-26 stsp 		*p = NULL; /* fall back on file I/O */
190 3b0f3d61 2020-01-22 neels 
191 c6eecea3 2020-07-26 stsp 	return fd;
192 3b0f3d61 2020-01-22 neels }