1 b7ba71f0 2020-10-07 stsp /* Produce ed(1) script output from a diff_result. */
  2 b7ba71f0 2020-10-07 stsp /*
  3 b7ba71f0 2020-10-07 stsp  * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
  4 b7ba71f0 2020-10-07 stsp  * Copyright (c) 2020 Stefan Sperling <stsp@openbsd.org>
  5 b7ba71f0 2020-10-07 stsp  *
  6 b7ba71f0 2020-10-07 stsp  * Permission to use, copy, modify, and distribute this software for any
  7 b7ba71f0 2020-10-07 stsp  * purpose with or without fee is hereby granted, provided that the above
  8 b7ba71f0 2020-10-07 stsp  * copyright notice and this permission notice appear in all copies.
  9 b7ba71f0 2020-10-07 stsp  *
 10 b7ba71f0 2020-10-07 stsp  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 11 b7ba71f0 2020-10-07 stsp  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 12 b7ba71f0 2020-10-07 stsp  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 13 b7ba71f0 2020-10-07 stsp  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 14 b7ba71f0 2020-10-07 stsp  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 15 b7ba71f0 2020-10-07 stsp  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 16 b7ba71f0 2020-10-07 stsp  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 17 b7ba71f0 2020-10-07 stsp  */
 18 b7ba71f0 2020-10-07 stsp 
 19 b7ba71f0 2020-10-07 stsp #include <errno.h>
 20 fe6d58fb 2020-11-14 naddy #include <stdint.h>
 21 b7ba71f0 2020-10-07 stsp #include <stdio.h>
 22 b7ba71f0 2020-10-07 stsp #include <stdlib.h>
 23 b7ba71f0 2020-10-07 stsp #include <stdbool.h>
 24 b7ba71f0 2020-10-07 stsp 
 25 b7ba71f0 2020-10-07 stsp #include <arraylist.h>
 26 b7ba71f0 2020-10-07 stsp #include <diff_main.h>
 27 b7ba71f0 2020-10-07 stsp #include <diff_output.h>
 28 b7ba71f0 2020-10-07 stsp 
 29 b7ba71f0 2020-10-07 stsp #include "diff_internal.h"
 30 b7ba71f0 2020-10-07 stsp 
 31 b7ba71f0 2020-10-07 stsp static int
 32 b7ba71f0 2020-10-07 stsp output_edscript_chunk(struct diff_output_info *outinfo,
 33 b7ba71f0 2020-10-07 stsp     FILE *dest, const struct diff_input_info *info,
 34 b7ba71f0 2020-10-07 stsp     const struct diff_result *result,
 35 26595c7d 2020-10-15 stsp     struct diff_chunk_context *cc)
 36 b7ba71f0 2020-10-07 stsp {
 37 b7ba71f0 2020-10-07 stsp 	off_t outoff = 0, *offp;
 38 b7ba71f0 2020-10-07 stsp 	int left_start, left_len, right_start, right_len;
 39 b7ba71f0 2020-10-07 stsp 	int rc;
 40 b7ba71f0 2020-10-07 stsp 
 41 b7ba71f0 2020-10-07 stsp 	left_len = cc->left.end - cc->left.start;
 42 b7ba71f0 2020-10-07 stsp 	if (left_len < 0)
 43 b7ba71f0 2020-10-07 stsp 		return EINVAL;
 44 c16dde50 2020-10-22 stsp 	else if (result->left->atoms.len == 0)
 45 ede9a86a 2020-10-07 stsp 		left_start = 0;
 46 b7ba71f0 2020-10-07 stsp 	else if (left_len == 0 && cc->left.start > 0)
 47 b7ba71f0 2020-10-07 stsp 		left_start = cc->left.start;
 48 b7ba71f0 2020-10-07 stsp 	else
 49 b7ba71f0 2020-10-07 stsp 		left_start = cc->left.start + 1;
 50 b7ba71f0 2020-10-07 stsp 
 51 b7ba71f0 2020-10-07 stsp 	right_len = cc->right.end - cc->right.start;
 52 b7ba71f0 2020-10-07 stsp 	if (right_len < 0)
 53 b7ba71f0 2020-10-07 stsp 		return EINVAL;
 54 c16dde50 2020-10-22 stsp 	else if (result->right->atoms.len == 0)
 55 ede9a86a 2020-10-07 stsp 		right_start = 0;
 56 b7ba71f0 2020-10-07 stsp 	else if (right_len == 0 && cc->right.start > 0)
 57 b7ba71f0 2020-10-07 stsp 		right_start = cc->right.start;
 58 b7ba71f0 2020-10-07 stsp 	else
 59 b7ba71f0 2020-10-07 stsp 		right_start = cc->right.start + 1;
 60 b7ba71f0 2020-10-07 stsp 
 61 26595c7d 2020-10-15 stsp 	if (left_len == 0) {
 62 26595c7d 2020-10-15 stsp 		/* addition */
 63 26595c7d 2020-10-15 stsp 		if (right_len == 1) {
 64 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%da%d\n", left_start, right_start);
 65 26595c7d 2020-10-15 stsp 		} else {
 66 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%da%d,%d\n", left_start,
 67 26595c7d 2020-10-15 stsp 			    right_start, cc->right.end);
 68 26595c7d 2020-10-15 stsp 		}
 69 26595c7d 2020-10-15 stsp 	} else if (right_len == 0) {
 70 26595c7d 2020-10-15 stsp 		/* deletion */
 71 b7ba71f0 2020-10-07 stsp 		if (left_len == 1) {
 72 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%dd%d\n", left_start,
 73 26595c7d 2020-10-15 stsp 			    right_start);
 74 b7ba71f0 2020-10-07 stsp 		} else {
 75 b7ba71f0 2020-10-07 stsp 			rc = fprintf(dest, "%d,%dd%d\n", left_start,
 76 b7ba71f0 2020-10-07 stsp 			    cc->left.end, right_start);
 77 b7ba71f0 2020-10-07 stsp 		}
 78 26595c7d 2020-10-15 stsp 	} else {
 79 26595c7d 2020-10-15 stsp 		/* change */
 80 26595c7d 2020-10-15 stsp 		if (left_len == 1 && right_len == 1) {
 81 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%dc%d\n", left_start, right_start);
 82 26595c7d 2020-10-15 stsp 		} else if (left_len == 1) {
 83 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%dc%d,%d\n", left_start,
 84 b7ba71f0 2020-10-07 stsp 			    right_start, cc->right.end);
 85 26595c7d 2020-10-15 stsp 		} else if (right_len == 1) {
 86 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%d,%dc%d\n", left_start,
 87 26595c7d 2020-10-15 stsp 			    cc->left.end, right_start);
 88 26595c7d 2020-10-15 stsp 		} else {
 89 26595c7d 2020-10-15 stsp 			rc = fprintf(dest, "%d,%dc%d,%d\n", left_start,
 90 26595c7d 2020-10-15 stsp 			    cc->left.end, right_start, cc->right.end);
 91 b7ba71f0 2020-10-07 stsp 		}
 92 26595c7d 2020-10-15 stsp 	}
 93 b7ba71f0 2020-10-07 stsp 	if (rc < 0)
 94 b7ba71f0 2020-10-07 stsp 		return errno;
 95 b7ba71f0 2020-10-07 stsp 	if (outinfo) {
 96 b7ba71f0 2020-10-07 stsp 		ARRAYLIST_ADD(offp, outinfo->line_offsets);
 97 b7ba71f0 2020-10-07 stsp 		if (offp == NULL)
 98 b7ba71f0 2020-10-07 stsp 			return ENOMEM;
 99 b7ba71f0 2020-10-07 stsp 		outoff += rc;
100 b7ba71f0 2020-10-07 stsp 		*offp = outoff;
101 b7ba71f0 2020-10-07 stsp 	}
102 b7ba71f0 2020-10-07 stsp 
103 b7ba71f0 2020-10-07 stsp 	return DIFF_RC_OK;
104 b7ba71f0 2020-10-07 stsp }
105 b7ba71f0 2020-10-07 stsp 
106 b7ba71f0 2020-10-07 stsp int
107 b7ba71f0 2020-10-07 stsp diff_output_edscript(struct diff_output_info **output_info,
108 b7ba71f0 2020-10-07 stsp     FILE *dest, const struct diff_input_info *info,
109 b7ba71f0 2020-10-07 stsp     const struct diff_result *result)
110 b7ba71f0 2020-10-07 stsp {
111 b7ba71f0 2020-10-07 stsp 	struct diff_output_info *outinfo = NULL;
112 26595c7d 2020-10-15 stsp 	struct diff_chunk_context cc = {};
113 e51ebd83 2020-11-21 stsp 	int atomizer_flags = (result->left->atomizer_flags|
114 e51ebd83 2020-11-21 stsp 	    result->right->atomizer_flags);
115 e51ebd83 2020-11-21 stsp 	int flags = (result->left->root->diff_flags |
116 e51ebd83 2020-11-21 stsp 	    result->right->root->diff_flags);
117 e51ebd83 2020-11-21 stsp 	bool force_text = (flags & DIFF_FLAG_FORCE_TEXT_DATA);
118 e51ebd83 2020-11-21 stsp 	bool have_binary = (atomizer_flags & DIFF_ATOMIZER_FOUND_BINARY_DATA);
119 b7ba71f0 2020-10-07 stsp 	int i, rc;
120 b7ba71f0 2020-10-07 stsp 
121 b7ba71f0 2020-10-07 stsp 	if (!result)
122 b7ba71f0 2020-10-07 stsp 		return EINVAL;
123 b7ba71f0 2020-10-07 stsp 	if (result->rc != DIFF_RC_OK)
124 b7ba71f0 2020-10-07 stsp 		return result->rc;
125 b7ba71f0 2020-10-07 stsp 
126 b7ba71f0 2020-10-07 stsp 	if (output_info) {
127 b7ba71f0 2020-10-07 stsp 		*output_info = diff_output_info_alloc();
128 b7ba71f0 2020-10-07 stsp 		if (*output_info == NULL)
129 b7ba71f0 2020-10-07 stsp 			return ENOMEM;
130 b7ba71f0 2020-10-07 stsp 		outinfo = *output_info;
131 b7ba71f0 2020-10-07 stsp 	}
132 b7ba71f0 2020-10-07 stsp 
133 e51ebd83 2020-11-21 stsp 	if (have_binary && !force_text) {
134 e51ebd83 2020-11-21 stsp 		for (i = 0; i < result->chunks.len; i++) {
135 e51ebd83 2020-11-21 stsp 			struct diff_chunk *c = &result->chunks.head[i];
136 e51ebd83 2020-11-21 stsp 			enum diff_chunk_type t = diff_chunk_type(c);
137 e51ebd83 2020-11-21 stsp 
138 e51ebd83 2020-11-21 stsp 			if (t != CHUNK_MINUS && t != CHUNK_PLUS)
139 e51ebd83 2020-11-21 stsp 				continue;
140 e51ebd83 2020-11-21 stsp 
141 e51ebd83 2020-11-21 stsp 			fprintf(dest, "Binary files %s and %s differ\n",
142 e4c510c1 2020-11-21 stsp 			    diff_output_get_label_left(info),
143 e4c510c1 2020-11-21 stsp 			    diff_output_get_label_right(info));
144 e51ebd83 2020-11-21 stsp 			break;
145 e51ebd83 2020-11-21 stsp 		}
146 e51ebd83 2020-11-21 stsp 
147 e51ebd83 2020-11-21 stsp 		return DIFF_RC_OK;
148 e51ebd83 2020-11-21 stsp 	}
149 e51ebd83 2020-11-21 stsp 
150 b7ba71f0 2020-10-07 stsp 	for (i = 0; i < result->chunks.len; i++) {
151 b7ba71f0 2020-10-07 stsp 		struct diff_chunk *chunk = &result->chunks.head[i];
152 b7ba71f0 2020-10-07 stsp 		enum diff_chunk_type t = diff_chunk_type(chunk);
153 26595c7d 2020-10-15 stsp 		struct diff_chunk_context next;
154 b7ba71f0 2020-10-07 stsp 
155 b7ba71f0 2020-10-07 stsp 		if (t != CHUNK_MINUS && t != CHUNK_PLUS)
156 b7ba71f0 2020-10-07 stsp 			continue;
157 b7ba71f0 2020-10-07 stsp 
158 cbf93b70 2020-10-16 stsp 		if (diff_chunk_context_empty(&cc)) {
159 26595c7d 2020-10-15 stsp 			/* Note down the start point, any number of subsequent
160 26595c7d 2020-10-15 stsp 			 * chunks may be joined up to this chunk by being
161 26595c7d 2020-10-15 stsp 			 * directly adjacent. */
162 26595c7d 2020-10-15 stsp 			diff_chunk_context_get(&cc, result, i, 0);
163 26595c7d 2020-10-15 stsp 			continue;
164 26595c7d 2020-10-15 stsp 		}
165 b7ba71f0 2020-10-07 stsp 
166 26595c7d 2020-10-15 stsp 		/* There already is a previous chunk noted down for being
167 26595c7d 2020-10-15 stsp 		 * printed. Does it join up with this one? */
168 26595c7d 2020-10-15 stsp 		diff_chunk_context_get(&next, result, i, 0);
169 26595c7d 2020-10-15 stsp 
170 26595c7d 2020-10-15 stsp 		if (diff_chunk_contexts_touch(&cc, &next)) {
171 26595c7d 2020-10-15 stsp 			/* This next context touches or overlaps the previous
172 26595c7d 2020-10-15 stsp 			 * one, join. */
173 26595c7d 2020-10-15 stsp 			diff_chunk_contexts_merge(&cc, &next);
174 b7ba71f0 2020-10-07 stsp 			continue;
175 26595c7d 2020-10-15 stsp 		}
176 b7ba71f0 2020-10-07 stsp 
177 26595c7d 2020-10-15 stsp 		rc = output_edscript_chunk(outinfo, dest, info, result, &cc);
178 b7ba71f0 2020-10-07 stsp 		if (rc != DIFF_RC_OK)
179 b7ba71f0 2020-10-07 stsp 			return rc;
180 26595c7d 2020-10-15 stsp 		cc = next;
181 b7ba71f0 2020-10-07 stsp 	}
182 b7ba71f0 2020-10-07 stsp 
183 cbf93b70 2020-10-16 stsp 	if (!diff_chunk_context_empty(&cc))
184 26595c7d 2020-10-15 stsp 		return output_edscript_chunk(outinfo, dest, info, result, &cc);
185 b7ba71f0 2020-10-07 stsp 	return DIFF_RC_OK;
186 b7ba71f0 2020-10-07 stsp }