1 fe621944 2020-11-10 stsp /* Output all lines of a diff_result. */
  2 fe621944 2020-11-10 stsp /*
  3 fe621944 2020-11-10 stsp  * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
  4 fe621944 2020-11-10 stsp  *
  5 fe621944 2020-11-10 stsp  * Permission to use, copy, modify, and distribute this software for any
  6 fe621944 2020-11-10 stsp  * purpose with or without fee is hereby granted, provided that the above
  7 fe621944 2020-11-10 stsp  * copyright notice and this permission notice appear in all copies.
  8 fe621944 2020-11-10 stsp  *
  9 fe621944 2020-11-10 stsp  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 10 fe621944 2020-11-10 stsp  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 11 fe621944 2020-11-10 stsp  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 12 fe621944 2020-11-10 stsp  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 13 fe621944 2020-11-10 stsp  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 14 fe621944 2020-11-10 stsp  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 15 fe621944 2020-11-10 stsp  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 16 fe621944 2020-11-10 stsp  */
 17 fe621944 2020-11-10 stsp 
 18 fe621944 2020-11-10 stsp #include <errno.h>
 19 f3c44083 2020-11-14 naddy #include <stdint.h>
 20 fe621944 2020-11-10 stsp #include <stdio.h>
 21 fe621944 2020-11-10 stsp #include <stdbool.h>
 22 fe621944 2020-11-10 stsp #include <stdlib.h>
 23 fe621944 2020-11-10 stsp 
 24 fe621944 2020-11-10 stsp #include <arraylist.h>
 25 fe621944 2020-11-10 stsp #include <diff_main.h>
 26 fe621944 2020-11-10 stsp #include <diff_output.h>
 27 fe621944 2020-11-10 stsp 
 28 fe621944 2020-11-10 stsp #include "diff_internal.h"
 29 fe621944 2020-11-10 stsp 
 30 f068d119 2022-09-02 stsp static int
 31 f068d119 2022-09-02 stsp output_plain_chunk(struct diff_output_info *outinfo,
 32 f068d119 2022-09-02 stsp     FILE *dest, const struct diff_input_info *info,
 33 f068d119 2022-09-02 stsp     const struct diff_result *result,
 34 e72b0983 2022-09-03 stsp     struct diff_chunk_context *cc, off_t *outoff, bool headers_only)
 35 f068d119 2022-09-02 stsp {
 36 e72b0983 2022-09-03 stsp 	off_t *offp;
 37 f068d119 2022-09-02 stsp 	int left_start, left_len, right_start, right_len;
 38 f068d119 2022-09-02 stsp 	int rc;
 39 f068d119 2022-09-02 stsp 	bool change = false;
 40 f068d119 2022-09-02 stsp 
 41 f068d119 2022-09-02 stsp 	left_len = cc->left.end - cc->left.start;
 42 f068d119 2022-09-02 stsp 	if (left_len < 0)
 43 f068d119 2022-09-02 stsp 		return EINVAL;
 44 f068d119 2022-09-02 stsp 	else if (result->left->atoms.len == 0)
 45 f068d119 2022-09-02 stsp 		left_start = 0;
 46 f068d119 2022-09-02 stsp 	else if (left_len == 0 && cc->left.start > 0)
 47 f068d119 2022-09-02 stsp 		left_start = cc->left.start;
 48 f068d119 2022-09-02 stsp 	else if (cc->left.end > 0)
 49 f068d119 2022-09-02 stsp 		left_start = cc->left.start + 1;
 50 f068d119 2022-09-02 stsp 	else
 51 f068d119 2022-09-02 stsp 		left_start = cc->left.start;
 52 f068d119 2022-09-02 stsp 
 53 f068d119 2022-09-02 stsp 	right_len = cc->right.end - cc->right.start;
 54 f068d119 2022-09-02 stsp 	if (right_len < 0)
 55 f068d119 2022-09-02 stsp 		return EINVAL;
 56 f068d119 2022-09-02 stsp 	else if (result->right->atoms.len == 0)
 57 f068d119 2022-09-02 stsp 		right_start = 0;
 58 f068d119 2022-09-02 stsp 	else if (right_len == 0 && cc->right.start > 0)
 59 f068d119 2022-09-02 stsp 		right_start = cc->right.start;
 60 f068d119 2022-09-02 stsp 	else if (cc->right.end > 0)
 61 f068d119 2022-09-02 stsp 		right_start = cc->right.start + 1;
 62 f068d119 2022-09-02 stsp 	else
 63 f068d119 2022-09-02 stsp 		right_start = cc->right.start;
 64 f068d119 2022-09-02 stsp 
 65 f068d119 2022-09-02 stsp 	if (left_len == 0) {
 66 f068d119 2022-09-02 stsp 		/* addition */
 67 f068d119 2022-09-02 stsp 		if (right_len == 1) {
 68 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%da%d\n", left_start, right_start);
 69 f068d119 2022-09-02 stsp 		} else {
 70 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%da%d,%d\n", left_start,
 71 f068d119 2022-09-02 stsp 			    right_start, cc->right.end);
 72 f068d119 2022-09-02 stsp 		}
 73 f068d119 2022-09-02 stsp 	} else if (right_len == 0) {
 74 f068d119 2022-09-02 stsp 		/* deletion */
 75 f068d119 2022-09-02 stsp 		if (left_len == 1) {
 76 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%dd%d\n", left_start,
 77 f068d119 2022-09-02 stsp 			    right_start);
 78 f068d119 2022-09-02 stsp 		} else {
 79 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%d,%dd%d\n", left_start,
 80 f068d119 2022-09-02 stsp 			    cc->left.end, right_start);
 81 f068d119 2022-09-02 stsp 		}
 82 f068d119 2022-09-02 stsp 	} else {
 83 f068d119 2022-09-02 stsp 		/* change */
 84 f068d119 2022-09-02 stsp 		change = true;
 85 f068d119 2022-09-02 stsp 		if (left_len == 1 && right_len == 1) {
 86 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%dc%d\n", left_start, right_start);
 87 f068d119 2022-09-02 stsp 		} else if (left_len == 1) {
 88 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%dc%d,%d\n", left_start,
 89 f068d119 2022-09-02 stsp 			    right_start, cc->right.end);
 90 f068d119 2022-09-02 stsp 		} else if (right_len == 1) {
 91 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%d,%dc%d\n", left_start,
 92 f068d119 2022-09-02 stsp 			    cc->left.end, right_start);
 93 f068d119 2022-09-02 stsp 		} else {
 94 f068d119 2022-09-02 stsp 			rc = fprintf(dest, "%d,%dc%d,%d\n", left_start,
 95 f068d119 2022-09-02 stsp 			    cc->left.end, right_start, cc->right.end);
 96 f068d119 2022-09-02 stsp 		}
 97 f068d119 2022-09-02 stsp 	}
 98 e72b0983 2022-09-03 stsp 	if (rc < 0)
 99 e72b0983 2022-09-03 stsp 		return errno;
100 e72b0983 2022-09-03 stsp 	if (outinfo) {
101 e72b0983 2022-09-03 stsp 		ARRAYLIST_ADD(offp, outinfo->line_offsets);
102 e72b0983 2022-09-03 stsp 		if (offp == NULL)
103 e72b0983 2022-09-03 stsp 			return ENOMEM;
104 e72b0983 2022-09-03 stsp 		*outoff += rc;
105 e72b0983 2022-09-03 stsp 		*offp = *outoff;
106 e72b0983 2022-09-03 stsp 	}
107 f068d119 2022-09-02 stsp 
108 f068d119 2022-09-02 stsp 	/*
109 f068d119 2022-09-02 stsp 	 * Now write out all the joined chunks.
110 f068d119 2022-09-02 stsp 	 *
111 f068d119 2022-09-02 stsp 	 * If the hunk denotes a change, it will come in the form of a deletion
112 f068d119 2022-09-02 stsp 	 * chunk followed by a addition chunk. Print a marker to break up the
113 f068d119 2022-09-02 stsp 	 * additions and deletions when this happens.
114 f068d119 2022-09-02 stsp 	 */
115 f068d119 2022-09-02 stsp 	int c_idx;
116 e72b0983 2022-09-03 stsp 	for (c_idx = cc->chunk.start; !headers_only && c_idx < cc->chunk.end;
117 e72b0983 2022-09-03 stsp 	    c_idx++) {
118 f068d119 2022-09-02 stsp 		const struct diff_chunk *c = &result->chunks.head[c_idx];
119 f068d119 2022-09-02 stsp 		if (c->left_count && !c->right_count)
120 f068d119 2022-09-02 stsp 			rc = diff_output_lines(outinfo, dest,
121 f068d119 2022-09-02 stsp 					  c->solved ? "< " : "?",
122 f068d119 2022-09-02 stsp 					  c->left_start, c->left_count);
123 f068d119 2022-09-02 stsp 		else if (c->right_count && !c->left_count) {
124 e72b0983 2022-09-03 stsp 			if (change) {
125 e72b0983 2022-09-03 stsp 				rc = fprintf(dest, "---\n");
126 e72b0983 2022-09-03 stsp 				if (rc < 0)
127 e72b0983 2022-09-03 stsp 					return errno;
128 e72b0983 2022-09-03 stsp 				if (outinfo) {
129 e72b0983 2022-09-03 stsp 					ARRAYLIST_ADD(offp,
130 e72b0983 2022-09-03 stsp 					    outinfo->line_offsets);
131 e72b0983 2022-09-03 stsp 					if (offp == NULL)
132 e72b0983 2022-09-03 stsp 						return ENOMEM;
133 e72b0983 2022-09-03 stsp 					*outoff += rc;
134 e72b0983 2022-09-03 stsp 					*offp = *outoff;
135 e72b0983 2022-09-03 stsp 				}
136 e72b0983 2022-09-03 stsp 			}
137 f068d119 2022-09-02 stsp 			rc = diff_output_lines(outinfo, dest,
138 f068d119 2022-09-02 stsp 					  c->solved ? "> " : "?",
139 f068d119 2022-09-02 stsp 					  c->right_start, c->right_count);
140 f068d119 2022-09-02 stsp 		}
141 f068d119 2022-09-02 stsp 		if (rc)
142 f068d119 2022-09-02 stsp 			return rc;
143 f068d119 2022-09-02 stsp 		if (cc->chunk.end == result->chunks.len) {
144 f068d119 2022-09-02 stsp 			rc = diff_output_trailing_newline_msg(outinfo, dest, c);
145 f068d119 2022-09-02 stsp 			if (rc != DIFF_RC_OK)
146 f068d119 2022-09-02 stsp 				return rc;
147 f068d119 2022-09-02 stsp 		}
148 f068d119 2022-09-02 stsp 	}
149 f068d119 2022-09-02 stsp 
150 f068d119 2022-09-02 stsp 	return DIFF_RC_OK;
151 f068d119 2022-09-02 stsp }
152 f068d119 2022-09-02 stsp 
153 fe621944 2020-11-10 stsp int
154 f068d119 2022-09-02 stsp diff_output_plain(struct diff_output_info **output_info,
155 f068d119 2022-09-02 stsp     FILE *dest, const struct diff_input_info *info,
156 e72b0983 2022-09-03 stsp     const struct diff_result *result, int hunk_headers_only)
157 fe621944 2020-11-10 stsp {
158 fe621944 2020-11-10 stsp 	struct diff_output_info *outinfo = NULL;
159 f068d119 2022-09-02 stsp 	struct diff_chunk_context cc = {};
160 f068d119 2022-09-02 stsp 	int atomizer_flags = (result->left->atomizer_flags|
161 f068d119 2022-09-02 stsp 	    result->right->atomizer_flags);
162 f068d119 2022-09-02 stsp 	int flags = (result->left->root->diff_flags |
163 f068d119 2022-09-02 stsp 	    result->right->root->diff_flags);
164 f068d119 2022-09-02 stsp 	bool force_text = (flags & DIFF_FLAG_FORCE_TEXT_DATA);
165 f068d119 2022-09-02 stsp 	bool have_binary = (atomizer_flags & DIFF_ATOMIZER_FOUND_BINARY_DATA);
166 fe621944 2020-11-10 stsp 	int i, rc;
167 e72b0983 2022-09-03 stsp 	off_t outoff = 0, *offp;
168 fe621944 2020-11-10 stsp 
169 fe621944 2020-11-10 stsp 	if (!result)
170 fe621944 2020-11-10 stsp 		return EINVAL;
171 fe621944 2020-11-10 stsp 	if (result->rc != DIFF_RC_OK)
172 fe621944 2020-11-10 stsp 		return result->rc;
173 f068d119 2022-09-02 stsp 
174 fe621944 2020-11-10 stsp 	if (output_info) {
175 fe621944 2020-11-10 stsp 		*output_info = diff_output_info_alloc();
176 fe621944 2020-11-10 stsp 		if (*output_info == NULL)
177 f068d119 2022-09-02 stsp 			return ENOMEM;
178 fe621944 2020-11-10 stsp 		outinfo = *output_info;
179 fe621944 2020-11-10 stsp 	}
180 fe621944 2020-11-10 stsp 
181 f068d119 2022-09-02 stsp 	if (have_binary && !force_text) {
182 f068d119 2022-09-02 stsp 		for (i = 0; i < result->chunks.len; i++) {
183 f068d119 2022-09-02 stsp 			struct diff_chunk *c = &result->chunks.head[i];
184 f068d119 2022-09-02 stsp 			enum diff_chunk_type t = diff_chunk_type(c);
185 f068d119 2022-09-02 stsp 
186 f068d119 2022-09-02 stsp 			if (t != CHUNK_MINUS && t != CHUNK_PLUS)
187 f068d119 2022-09-02 stsp 				continue;
188 f068d119 2022-09-02 stsp 
189 e72b0983 2022-09-03 stsp 			rc = fprintf(dest, "Binary files %s and %s differ\n",
190 f068d119 2022-09-02 stsp 			    diff_output_get_label_left(info),
191 f068d119 2022-09-02 stsp 			    diff_output_get_label_right(info));
192 e72b0983 2022-09-03 stsp 			if (rc < 0)
193 e72b0983 2022-09-03 stsp 				return errno;
194 e72b0983 2022-09-03 stsp 			if (outinfo) {
195 e72b0983 2022-09-03 stsp 				ARRAYLIST_ADD(offp, outinfo->line_offsets);
196 e72b0983 2022-09-03 stsp 				if (offp == NULL)
197 e72b0983 2022-09-03 stsp 					return ENOMEM;
198 e72b0983 2022-09-03 stsp 				outoff += rc;
199 e72b0983 2022-09-03 stsp 				*offp = outoff;
200 e72b0983 2022-09-03 stsp 			}
201 f068d119 2022-09-02 stsp 			break;
202 f068d119 2022-09-02 stsp 		}
203 f068d119 2022-09-02 stsp 
204 f068d119 2022-09-02 stsp 		return DIFF_RC_OK;
205 f068d119 2022-09-02 stsp 	}
206 f068d119 2022-09-02 stsp 
207 fe621944 2020-11-10 stsp 	for (i = 0; i < result->chunks.len; i++) {
208 f068d119 2022-09-02 stsp 		struct diff_chunk *chunk = &result->chunks.head[i];
209 f068d119 2022-09-02 stsp 		enum diff_chunk_type t = diff_chunk_type(chunk);
210 f068d119 2022-09-02 stsp 		struct diff_chunk_context next;
211 f068d119 2022-09-02 stsp 
212 f068d119 2022-09-02 stsp 		if (t != CHUNK_MINUS && t != CHUNK_PLUS)
213 f068d119 2022-09-02 stsp 			continue;
214 f068d119 2022-09-02 stsp 
215 f068d119 2022-09-02 stsp 		if (diff_chunk_context_empty(&cc)) {
216 f068d119 2022-09-02 stsp 			/* Note down the start point, any number of subsequent
217 f068d119 2022-09-02 stsp 			 * chunks may be joined up to this chunk by being
218 f068d119 2022-09-02 stsp 			 * directly adjacent. */
219 f068d119 2022-09-02 stsp 			diff_chunk_context_get(&cc, result, i, 0);
220 f068d119 2022-09-02 stsp 			continue;
221 f068d119 2022-09-02 stsp 		}
222 f068d119 2022-09-02 stsp 
223 f068d119 2022-09-02 stsp 		/* There already is a previous chunk noted down for being
224 f068d119 2022-09-02 stsp 		 * printed. Does it join up with this one? */
225 f068d119 2022-09-02 stsp 		diff_chunk_context_get(&next, result, i, 0);
226 f068d119 2022-09-02 stsp 
227 f068d119 2022-09-02 stsp 		if (diff_chunk_contexts_touch(&cc, &next)) {
228 f068d119 2022-09-02 stsp 			/* This next context touches or overlaps the previous
229 f068d119 2022-09-02 stsp 			 * one, join. */
230 f068d119 2022-09-02 stsp 			diff_chunk_contexts_merge(&cc, &next);
231 f068d119 2022-09-02 stsp 			/* When we merge the last chunk we can end up with one
232 f068d119 2022-09-02 stsp 			 * hanging chunk and have to come back for it after the
233 f068d119 2022-09-02 stsp 			 * loop */
234 f068d119 2022-09-02 stsp 			continue;
235 f068d119 2022-09-02 stsp 		}
236 e72b0983 2022-09-03 stsp 		rc = output_plain_chunk(outinfo, dest, info, result, &cc,
237 e72b0983 2022-09-03 stsp 		    &outoff, hunk_headers_only);
238 f068d119 2022-09-02 stsp 		if (rc != DIFF_RC_OK)
239 fe621944 2020-11-10 stsp 			return rc;
240 f068d119 2022-09-02 stsp 		cc = next;
241 fe621944 2020-11-10 stsp 	}
242 f068d119 2022-09-02 stsp 	if (!diff_chunk_context_empty(&cc))
243 e72b0983 2022-09-03 stsp 		return output_plain_chunk(outinfo, dest, info, result, &cc,
244 e72b0983 2022-09-03 stsp 		    &outoff, hunk_headers_only);
245 fe621944 2020-11-10 stsp 	return DIFF_RC_OK;
246 fe621944 2020-11-10 stsp }