1 3b0f3d61 2020-01-22 neels /* Common parts for printing diff output */
  2 3b0f3d61 2020-01-22 neels /*
  3 3b0f3d61 2020-01-22 neels  * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
  4 3b0f3d61 2020-01-22 neels  *
  5 3b0f3d61 2020-01-22 neels  * Permission to use, copy, modify, and distribute this software for any
  6 3b0f3d61 2020-01-22 neels  * purpose with or without fee is hereby granted, provided that the above
  7 3b0f3d61 2020-01-22 neels  * copyright notice and this permission notice appear in all copies.
  8 3b0f3d61 2020-01-22 neels  *
  9 3b0f3d61 2020-01-22 neels  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 10 3b0f3d61 2020-01-22 neels  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 11 3b0f3d61 2020-01-22 neels  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 12 3b0f3d61 2020-01-22 neels  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 13 3b0f3d61 2020-01-22 neels  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 14 3b0f3d61 2020-01-22 neels  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 15 3b0f3d61 2020-01-22 neels  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 16 3b0f3d61 2020-01-22 neels  */
 17 3b0f3d61 2020-01-22 neels 
 18 6f26cb2e 2020-09-20 stsp #include <errno.h>
 19 e10a628a 2020-09-16 stsp #include <inttypes.h>
 20 e10a628a 2020-09-16 stsp #include <stdbool.h>
 21 e10a628a 2020-09-16 stsp #include <stdio.h>
 22 e10a628a 2020-09-16 stsp #include <stdlib.h>
 23 c6eecea3 2020-07-26 stsp #include <unistd.h>
 24 c6eecea3 2020-07-26 stsp 
 25 1dfba055 2020-10-07 stsp #include <arraylist.h>
 26 1dfba055 2020-10-07 stsp #include <diff_main.h>
 27 1dfba055 2020-10-07 stsp #include <diff_output.h>
 28 3b0f3d61 2020-01-22 neels 
 29 85ab4559 2020-09-22 stsp #include "diff_internal.h"
 30 85ab4559 2020-09-22 stsp 
 31 6f26cb2e 2020-09-20 stsp static int
 32 6f26cb2e 2020-09-20 stsp get_atom_byte(int *ch, struct diff_atom *atom, off_t off)
 33 c6eecea3 2020-07-26 stsp {
 34 c6eecea3 2020-07-26 stsp 	off_t cur;
 35 c6eecea3 2020-07-26 stsp 
 36 6f26cb2e 2020-09-20 stsp 	if (atom->at != NULL) {
 37 6f26cb2e 2020-09-20 stsp 		*ch = atom->at[off];
 38 6f26cb2e 2020-09-20 stsp 		return 0;
 39 6f26cb2e 2020-09-20 stsp 	}
 40 c6eecea3 2020-07-26 stsp 
 41 ad5b3f85 2020-10-12 neels 	cur = ftello(atom->root->f);
 42 c6eecea3 2020-07-26 stsp 	if (cur == -1)
 43 6f26cb2e 2020-09-20 stsp 		return errno;
 44 c6eecea3 2020-07-26 stsp 
 45 c6eecea3 2020-07-26 stsp 	if (cur != atom->pos + off &&
 46 ad5b3f85 2020-10-12 neels 	    fseeko(atom->root->f, atom->pos + off, SEEK_SET) == -1)
 47 6f26cb2e 2020-09-20 stsp 		return errno;
 48 c6eecea3 2020-07-26 stsp 
 49 ad5b3f85 2020-10-12 neels 	*ch = fgetc(atom->root->f);
 50 ad5b3f85 2020-10-12 neels 	if (*ch == EOF && ferror(atom->root->f))
 51 6f26cb2e 2020-09-20 stsp 		return errno;
 52 c6eecea3 2020-07-26 stsp 
 53 6f26cb2e 2020-09-20 stsp 	return 0;
 54 c6eecea3 2020-07-26 stsp }
 55 c6eecea3 2020-07-26 stsp 
 56 6f26cb2e 2020-09-20 stsp int
 57 2c20a3ed 2020-09-22 stsp diff_output_lines(struct diff_output_info *outinfo, FILE *dest,
 58 2c20a3ed 2020-09-22 stsp 		  const char *prefix, struct diff_atom *start_atom,
 59 0d27172a 2020-05-06 neels 		  unsigned int count)
 60 3b0f3d61 2020-01-22 neels {
 61 3b0f3d61 2020-01-22 neels 	struct diff_atom *atom;
 62 2c20a3ed 2020-09-22 stsp 	off_t outoff = 0, *offp;
 63 6f26cb2e 2020-09-20 stsp 	int rc;
 64 2c20a3ed 2020-09-22 stsp 
 65 2c20a3ed 2020-09-22 stsp 	if (outinfo && outinfo->line_offsets.len > 0) {
 66 2c20a3ed 2020-09-22 stsp 		unsigned int idx = outinfo->line_offsets.len - 1;
 67 2c20a3ed 2020-09-22 stsp 		outoff = outinfo->line_offsets.head[idx];
 68 2c20a3ed 2020-09-22 stsp 	}
 69 2c20a3ed 2020-09-22 stsp 
 70 3b0f3d61 2020-01-22 neels 	foreach_diff_atom(atom, start_atom, count) {
 71 2c20a3ed 2020-09-22 stsp 		off_t outlen = 0;
 72 6f26cb2e 2020-09-20 stsp 		int i, ch;
 73 3b0f3d61 2020-01-22 neels 		unsigned int len = atom->len;
 74 2c20a3ed 2020-09-22 stsp 		rc = fprintf(dest, "%s", prefix);
 75 2c20a3ed 2020-09-22 stsp 		if (rc < 0)
 76 2c20a3ed 2020-09-22 stsp 			return errno;
 77 2c20a3ed 2020-09-22 stsp 		outlen += rc;
 78 c6eecea3 2020-07-26 stsp 		if (len) {
 79 6f26cb2e 2020-09-20 stsp 			rc = get_atom_byte(&ch, atom, len - 1);
 80 6f26cb2e 2020-09-20 stsp 			if (rc)
 81 6f26cb2e 2020-09-20 stsp 				return rc;
 82 c6eecea3 2020-07-26 stsp 			if (ch == '\n')
 83 3b0f3d61 2020-01-22 neels 				len--;
 84 c6eecea3 2020-07-26 stsp 			if (len) {
 85 6f26cb2e 2020-09-20 stsp 				rc = get_atom_byte(&ch, atom, len - 1);
 86 6f26cb2e 2020-09-20 stsp 				if (rc)
 87 6f26cb2e 2020-09-20 stsp 					return rc;
 88 c6eecea3 2020-07-26 stsp 				if (ch == '\r')
 89 c6eecea3 2020-07-26 stsp 					len--;
 90 c6eecea3 2020-07-26 stsp 			}
 91 3b0f3d61 2020-01-22 neels 		}
 92 3b0f3d61 2020-01-22 neels 
 93 3b0f3d61 2020-01-22 neels 		for (i = 0; i < len; i++) {
 94 6f26cb2e 2020-09-20 stsp 			rc = get_atom_byte(&ch, atom, i);
 95 6f26cb2e 2020-09-20 stsp 			if (rc)
 96 6f26cb2e 2020-09-20 stsp 				return rc;
 97 5ed6e4d2 2020-10-17 stsp 			rc = fprintf(dest, "%c", (unsigned char)ch);
 98 2c20a3ed 2020-09-22 stsp 			if (rc < 0)
 99 2c20a3ed 2020-09-22 stsp 				return errno;
100 2c20a3ed 2020-09-22 stsp 			outlen += rc;
101 3b0f3d61 2020-01-22 neels 		}
102 2c20a3ed 2020-09-22 stsp 		rc = fprintf(dest, "\n");
103 2c20a3ed 2020-09-22 stsp 		if (rc < 0)
104 2c20a3ed 2020-09-22 stsp 			return errno;
105 2c20a3ed 2020-09-22 stsp 		outlen += rc;
106 2c20a3ed 2020-09-22 stsp 		if (outinfo) {
107 2c20a3ed 2020-09-22 stsp 			ARRAYLIST_ADD(offp, outinfo->line_offsets);
108 dabc1008 2020-09-22 stsp 			if (offp == NULL)
109 dabc1008 2020-09-22 stsp 				return ENOMEM;
110 2c20a3ed 2020-09-22 stsp 			outoff += outlen;
111 2c20a3ed 2020-09-22 stsp 			*offp = outoff;
112 2c20a3ed 2020-09-22 stsp 		}
113 3b0f3d61 2020-01-22 neels 	}
114 6f26cb2e 2020-09-20 stsp 
115 2c20a3ed 2020-09-22 stsp 	return DIFF_RC_OK;
116 3b0f3d61 2020-01-22 neels }
117 24b5052a 2020-09-22 stsp 
118 2c20a3ed 2020-09-22 stsp int
119 2c20a3ed 2020-09-22 stsp diff_output_chunk_left_version(struct diff_output_info **output_info,
120 2c20a3ed 2020-09-22 stsp 			       FILE *dest,
121 24b5052a 2020-09-22 stsp 			       const struct diff_input_info *info,
122 24b5052a 2020-09-22 stsp 			       const struct diff_result *result,
123 24b5052a 2020-09-22 stsp 			       const struct diff_chunk_context *cc)
124 24b5052a 2020-09-22 stsp {
125 8cba9b5e 2020-09-22 stsp 	int rc, c_idx;
126 2c20a3ed 2020-09-22 stsp 	struct diff_output_info *outinfo = NULL;
127 24b5052a 2020-09-22 stsp 
128 24b5052a 2020-09-22 stsp 	if (diff_range_empty(&cc->left))
129 2c20a3ed 2020-09-22 stsp 		return DIFF_RC_OK;
130 24b5052a 2020-09-22 stsp 
131 2c20a3ed 2020-09-22 stsp 	if (output_info) {
132 2c20a3ed 2020-09-22 stsp 		*output_info = diff_output_info_alloc();
133 2c20a3ed 2020-09-22 stsp 		if (*output_info == NULL)
134 2c20a3ed 2020-09-22 stsp 			return ENOMEM;
135 2c20a3ed 2020-09-22 stsp 		outinfo = *output_info;
136 2c20a3ed 2020-09-22 stsp 	}
137 2c20a3ed 2020-09-22 stsp 
138 24b5052a 2020-09-22 stsp 	/* Write out all chunks on the left side. */
139 24b5052a 2020-09-22 stsp 	for (c_idx = cc->chunk.start; c_idx < cc->chunk.end; c_idx++) {
140 24b5052a 2020-09-22 stsp 		const struct diff_chunk *c = &result->chunks.head[c_idx];
141 24b5052a 2020-09-22 stsp 
142 fde86f3d 2020-10-07 stsp 		if (c->left_count) {
143 8cba9b5e 2020-09-22 stsp 			rc = diff_output_lines(outinfo, dest, "",
144 8cba9b5e 2020-09-22 stsp 			    c->left_start, c->left_count);
145 8cba9b5e 2020-09-22 stsp 			if (rc)
146 8cba9b5e 2020-09-22 stsp 				return rc;
147 fde86f3d 2020-10-07 stsp 		}
148 24b5052a 2020-09-22 stsp 	}
149 2c20a3ed 2020-09-22 stsp 
150 2c20a3ed 2020-09-22 stsp 	return DIFF_RC_OK;
151 24b5052a 2020-09-22 stsp }
152 24b5052a 2020-09-22 stsp 
153 2c20a3ed 2020-09-22 stsp int
154 2c20a3ed 2020-09-22 stsp diff_output_chunk_right_version(struct diff_output_info **output_info,
155 2c20a3ed 2020-09-22 stsp 				FILE *dest,
156 24b5052a 2020-09-22 stsp 				const struct diff_input_info *info,
157 24b5052a 2020-09-22 stsp 				const struct diff_result *result,
158 24b5052a 2020-09-22 stsp 				const struct diff_chunk_context *cc)
159 24b5052a 2020-09-22 stsp {
160 8cba9b5e 2020-09-22 stsp 	int rc, c_idx;
161 2c20a3ed 2020-09-22 stsp 	struct diff_output_info *outinfo = NULL;
162 24b5052a 2020-09-22 stsp 
163 24b5052a 2020-09-22 stsp 	if (diff_range_empty(&cc->right))
164 2c20a3ed 2020-09-22 stsp 		return DIFF_RC_OK;
165 24b5052a 2020-09-22 stsp 
166 2c20a3ed 2020-09-22 stsp 	if (output_info) {
167 2c20a3ed 2020-09-22 stsp 		*output_info = diff_output_info_alloc();
168 2c20a3ed 2020-09-22 stsp 		if (*output_info == NULL)
169 2c20a3ed 2020-09-22 stsp 			return ENOMEM;
170 2c20a3ed 2020-09-22 stsp 		outinfo = *output_info;
171 2c20a3ed 2020-09-22 stsp 	}
172 2c20a3ed 2020-09-22 stsp 
173 24b5052a 2020-09-22 stsp 	/* Write out all chunks on the right side. */
174 24b5052a 2020-09-22 stsp 	for (c_idx = cc->chunk.start; c_idx < cc->chunk.end; c_idx++) {
175 24b5052a 2020-09-22 stsp 		const struct diff_chunk *c = &result->chunks.head[c_idx];
176 24b5052a 2020-09-22 stsp 
177 8cba9b5e 2020-09-22 stsp 		if (c->right_count) {
178 8cba9b5e 2020-09-22 stsp 			rc = diff_output_lines(outinfo, dest, "", c->right_start,
179 24b5052a 2020-09-22 stsp 			    c->right_count);
180 8cba9b5e 2020-09-22 stsp 			if (rc)
181 8cba9b5e 2020-09-22 stsp 				return rc;
182 8cba9b5e 2020-09-22 stsp 		}
183 24b5052a 2020-09-22 stsp 	}
184 2c20a3ed 2020-09-22 stsp 
185 2c20a3ed 2020-09-22 stsp 	return DIFF_RC_OK;
186 24b5052a 2020-09-22 stsp }
187 24b5052a 2020-09-22 stsp 
188 7021523c 2020-10-16 stsp int
189 7021523c 2020-10-16 stsp diff_output_trailing_newline_msg(struct diff_output_info *outinfo, FILE *dest,
190 7021523c 2020-10-16 stsp 				 const struct diff_chunk *c)
191 7021523c 2020-10-16 stsp {
192 7021523c 2020-10-16 stsp 	enum diff_chunk_type chunk_type = diff_chunk_type(c);
193 7021523c 2020-10-16 stsp 	struct diff_atom *atom, *start_atom;
194 7021523c 2020-10-16 stsp 	unsigned int atom_count;
195 7021523c 2020-10-16 stsp 	int rc, ch;
196 7021523c 2020-10-16 stsp 	off_t outoff = 0, *offp;
197 7021523c 2020-10-16 stsp 
198 7021523c 2020-10-16 stsp 	if (chunk_type == CHUNK_MINUS || chunk_type == CHUNK_SAME) {
199 7021523c 2020-10-16 stsp 		start_atom = c->left_start;
200 7021523c 2020-10-16 stsp 		atom_count = c->left_count;
201 7021523c 2020-10-16 stsp 	} else if (chunk_type == CHUNK_PLUS) {
202 7021523c 2020-10-16 stsp 		start_atom = c->right_start;
203 7021523c 2020-10-16 stsp 		atom_count = c->right_count;
204 7021523c 2020-10-16 stsp 	} else
205 7021523c 2020-10-16 stsp 		return EINVAL;
206 7021523c 2020-10-16 stsp 
207 7021523c 2020-10-16 stsp 	/* Locate the last atom. */
208 1b3c539b 2020-10-16 stsp 	if (atom_count == 0)
209 1b3c539b 2020-10-16 stsp 		return EINVAL;
210 1b3c539b 2020-10-16 stsp 	atom = &start_atom[atom_count - 1];
211 7021523c 2020-10-16 stsp 
212 7021523c 2020-10-16 stsp 	rc = get_atom_byte(&ch, atom, atom->len - 1);
213 7021523c 2020-10-16 stsp 	if (rc != DIFF_RC_OK)
214 7021523c 2020-10-16 stsp 		return rc;
215 7021523c 2020-10-16 stsp 
216 7021523c 2020-10-16 stsp 	if (ch != '\n') {
217 7021523c 2020-10-16 stsp 		if (outinfo && outinfo->line_offsets.len > 0) {
218 7021523c 2020-10-16 stsp 			unsigned int idx = outinfo->line_offsets.len - 1;
219 7021523c 2020-10-16 stsp 			outoff = outinfo->line_offsets.head[idx];
220 7021523c 2020-10-16 stsp 		}
221 7021523c 2020-10-16 stsp 		rc = fprintf(dest, "\\ No newline at end of file\n");
222 7021523c 2020-10-16 stsp 		if (rc < 0)
223 7021523c 2020-10-16 stsp 			return errno;
224 7021523c 2020-10-16 stsp 		if (outinfo) {
225 7021523c 2020-10-16 stsp 			ARRAYLIST_ADD(offp, outinfo->line_offsets);
226 7021523c 2020-10-16 stsp 			if (offp == NULL)
227 7021523c 2020-10-16 stsp 				return ENOMEM;
228 7021523c 2020-10-16 stsp 			outoff += rc;
229 7021523c 2020-10-16 stsp 			*offp = outoff;
230 7021523c 2020-10-16 stsp 		}
231 7021523c 2020-10-16 stsp 	}
232 7021523c 2020-10-16 stsp 
233 7021523c 2020-10-16 stsp 	return DIFF_RC_OK;
234 7021523c 2020-10-16 stsp }
235 7021523c 2020-10-16 stsp 
236 2c20a3ed 2020-09-22 stsp struct diff_output_info *
237 2c20a3ed 2020-09-22 stsp diff_output_info_alloc(void)
238 2c20a3ed 2020-09-22 stsp {
239 2c20a3ed 2020-09-22 stsp 	struct diff_output_info *output_info;
240 2c20a3ed 2020-09-22 stsp 	off_t *offp;
241 2c20a3ed 2020-09-22 stsp 
242 2c20a3ed 2020-09-22 stsp 	output_info = malloc(sizeof(*output_info));
243 2c20a3ed 2020-09-22 stsp 	if (output_info != NULL) {
244 2c20a3ed 2020-09-22 stsp 		ARRAYLIST_INIT(output_info->line_offsets, 128);
245 2c20a3ed 2020-09-22 stsp 		ARRAYLIST_ADD(offp, output_info->line_offsets);
246 dabc1008 2020-09-22 stsp 		if (offp == NULL) {
247 dabc1008 2020-09-22 stsp 			diff_output_info_free(output_info);
248 dabc1008 2020-09-22 stsp 			return NULL;
249 dabc1008 2020-09-22 stsp 		}
250 2c20a3ed 2020-09-22 stsp 		*offp = 0;
251 2c20a3ed 2020-09-22 stsp 	}
252 2c20a3ed 2020-09-22 stsp 	return output_info;
253 2c20a3ed 2020-09-22 stsp }
254 2c20a3ed 2020-09-22 stsp 
255 2c20a3ed 2020-09-22 stsp void
256 2c20a3ed 2020-09-22 stsp diff_output_info_free(struct diff_output_info *output_info)
257 2c20a3ed 2020-09-22 stsp {
258 2c20a3ed 2020-09-22 stsp 	ARRAYLIST_FREE(output_info->line_offsets);
259 2c20a3ed 2020-09-22 stsp 	free(output_info);
260 2c20a3ed 2020-09-22 stsp }