t/helper: ignore only executable files
[git/git.git] / xdiff / xemit.c
CommitLineData
3443546f
LT
1/*
2 * LibXDiff by Davide Libenzi ( File Differential Library )
3 * Copyright (C) 2003 Davide Libenzi
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
48425792
TZ
16 * License along with this library; if not, see
17 * <http://www.gnu.org/licenses/>.
3443546f
LT
18 *
19 * Davide Libenzi <davidel@xmailserver.org>
20 *
21 */
22
23#include "xinclude.h"
24
3443546f
LT
25static long xdl_get_rec(xdfile_t *xdf, long ri, char const **rec) {
26
27 *rec = xdf->recs[ri]->ptr;
28
29 return xdf->recs[ri]->size;
30}
31
32
33static int xdl_emit_record(xdfile_t *xdf, long ri, char const *pre, xdemitcb_t *ecb) {
34 long size, psize = strlen(pre);
35 char const *rec;
36
37 size = xdl_get_rec(xdf, ri, &rec);
38 if (xdl_emit_diffrec(rec, size, pre, psize, ecb) < 0) {
39
40 return -1;
41 }
42
43 return 0;
44}
45
46
47/*
48 * Starting at the passed change atom, find the latest change atom to be included
49 * inside the differential hunk according to the specified configuration.
36617af7 50 * Also advance xscr if the first changes must be discarded.
3443546f 51 */
36617af7
AP
52xdchange_t *xdl_get_hunk(xdchange_t **xscr, xdemitconf_t const *xecfg)
53{
54 xdchange_t *xch, *xchp, *lxch;
6d0e674a 55 long max_common = 2 * xecfg->ctxlen + xecfg->interhunkctxlen;
36617af7
AP
56 long max_ignorable = xecfg->ctxlen;
57 unsigned long ignored = 0; /* number of ignored blank lines */
58
59 /* remove ignorable changes that are too far before other changes */
60 for (xchp = *xscr; xchp && xchp->ignore; xchp = xchp->next) {
61 xch = xchp->next;
62
63 if (xch == NULL ||
64 xch->i1 - (xchp->i1 + xchp->chg1) >= max_ignorable)
65 *xscr = xch;
66 }
67
68 if (*xscr == NULL)
69 return NULL;
70
71 lxch = *xscr;
3443546f 72
36617af7
AP
73 for (xchp = *xscr, xch = xchp->next; xch; xchp = xch, xch = xch->next) {
74 long distance = xch->i1 - (xchp->i1 + xchp->chg1);
75 if (distance > max_common)
3443546f
LT
76 break;
77
36617af7
AP
78 if (distance < max_ignorable && (!xch->ignore || lxch == xchp)) {
79 lxch = xch;
80 ignored = 0;
81 } else if (distance < max_ignorable && xch->ignore) {
82 ignored += xch->chg2;
83 } else if (lxch != xchp &&
84 xch->i1 + ignored - (lxch->i1 + lxch->chg1) > max_common) {
85 break;
86 } else if (!xch->ignore) {
87 lxch = xch;
88 ignored = 0;
89 } else {
90 ignored += xch->chg2;
91 }
92 }
93
94 return lxch;
3443546f
LT
95}
96
97
f258475a
JH
98static long def_ff(const char *rec, long len, char *buf, long sz, void *priv)
99{
100 if (len > 0 &&
101 (isalpha((unsigned char)*rec) || /* identifier? */
c01499ef 102 *rec == '_' || /* also identifier? */
f258475a
JH
103 *rec == '$')) { /* identifiers from VMS and other esoterico */
104 if (len > sz)
105 len = sz;
106 while (0 < len && isspace((unsigned char)rec[len - 1]))
107 len--;
108 memcpy(buf, rec, len);
109 return len;
110 }
111 return -1;
112}
113
ff2981f7
RS
114static long match_func_rec(xdfile_t *xdf, xdemitconf_t const *xecfg, long ri,
115 char *buf, long sz)
116{
117 const char *rec;
118 long len = xdl_get_rec(xdf, ri, &rec);
119 if (!xecfg->find_func)
120 return def_ff(rec, len, buf, sz, xecfg->find_func_priv);
121 return xecfg->find_func(rec, len, buf, sz, xecfg->find_func_priv);
122}
123
cde32bf6
RS
124static int is_func_rec(xdfile_t *xdf, xdemitconf_t const *xecfg, long ri)
125{
126 char dummy[1];
127 return match_func_rec(xdf, xecfg, ri, dummy, sizeof(dummy)) >= 0;
128}
129
f99f4b36
RS
130struct func_line {
131 long len;
132 char buf[80];
133};
134
14937c2c 135static long get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
f99f4b36
RS
136 struct func_line *func_line, long start, long limit)
137{
14937c2c
RS
138 long l, size, step = (start > limit) ? -1 : 1;
139 char *buf, dummy[1];
f99f4b36 140
14937c2c
RS
141 buf = func_line ? func_line->buf : dummy;
142 size = func_line ? sizeof(func_line->buf) : sizeof(dummy);
143
144 for (l = start; l != limit && 0 <= l && l < xe->xdf1.nrec; l += step) {
ff2981f7 145 long len = match_func_rec(&xe->xdf1, xecfg, l, buf, size);
f99f4b36 146 if (len >= 0) {
14937c2c
RS
147 if (func_line)
148 func_line->len = len;
149 return l;
f99f4b36
RS
150 }
151 }
14937c2c 152 return -1;
f99f4b36
RS
153}
154
392f6d31
RS
155static int is_empty_rec(xdfile_t *xdf, long ri)
156{
157 const char *rec;
158 long len = xdl_get_rec(xdf, ri, &rec);
159
160 while (len > 0 && XDL_ISSPACE(*rec)) {
161 rec++;
162 len--;
163 }
164 return !len;
165}
166
3443546f
LT
167int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
168 xdemitconf_t const *xecfg) {
169 long s1, s2, e1, e2, lctx;
170 xdchange_t *xch, *xche;
c099789b 171 long funclineprev = -1;
f99f4b36 172 struct func_line func_line = { 0 };
3443546f 173
8e24cbae 174 for (xch = xscr; xch; xch = xche->next) {
36617af7
AP
175 xche = xdl_get_hunk(&xch, xecfg);
176 if (!xch)
177 break;
3443546f
LT
178
179 s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);
180 s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);
181
14937c2c 182 if (xecfg->flags & XDL_EMIT_FUNCCONTEXT) {
6d5badb2
RS
183 long fs1, i1 = xch->i1;
184
185 /* Appended chunk? */
186 if (i1 >= xe->xdf1.nrec) {
392f6d31 187 long i2 = xch->i2;
6d5badb2
RS
188
189 /*
190 * We don't need additional context if
540d3eb0 191 * a whole function was added.
6d5badb2 192 */
540d3eb0 193 while (i2 < xe->xdf2.nrec) {
cde32bf6 194 if (is_func_rec(&xe->xdf2, xecfg, i2))
540d3eb0 195 goto post_context_calculation;
392f6d31 196 i2++;
540d3eb0 197 }
6d5badb2
RS
198
199 /*
200 * Otherwise get more context from the
201 * pre-image.
202 */
203 i1 = xe->xdf1.nrec - 1;
204 }
205
206 fs1 = get_func_line(xe, xecfg, NULL, i1, -1);
5c3ed90f
RS
207 while (fs1 > 0 && !is_empty_rec(&xe->xdf1, fs1 - 1) &&
208 !is_func_rec(&xe->xdf1, xecfg, fs1 - 1))
209 fs1--;
14937c2c
RS
210 if (fs1 < 0)
211 fs1 = 0;
212 if (fs1 < s1) {
b777f3fd 213 s2 = XDL_MAX(s2 - (s1 - fs1), 0);
14937c2c
RS
214 s1 = fs1;
215 }
216 }
217
6d5badb2 218 post_context_calculation:
3443546f
LT
219 lctx = xecfg->ctxlen;
220 lctx = XDL_MIN(lctx, xe->xdf1.nrec - (xche->i1 + xche->chg1));
221 lctx = XDL_MIN(lctx, xe->xdf2.nrec - (xche->i2 + xche->chg2));
222
223 e1 = xche->i1 + xche->chg1 + lctx;
224 e2 = xche->i2 + xche->chg2 + lctx;
225
14937c2c
RS
226 if (xecfg->flags & XDL_EMIT_FUNCCONTEXT) {
227 long fe1 = get_func_line(xe, xecfg, NULL,
228 xche->i1 + xche->chg1,
229 xe->xdf1.nrec);
9e6a4cfc
RS
230 while (fe1 > 0 && is_empty_rec(&xe->xdf1, fe1 - 1))
231 fe1--;
14937c2c
RS
232 if (fe1 < 0)
233 fe1 = xe->xdf1.nrec;
234 if (fe1 > e1) {
b777f3fd 235 e2 = XDL_MIN(e2 + (fe1 - e1), xe->xdf2.nrec);
14937c2c
RS
236 e1 = fe1;
237 }
238
239 /*
240 * Overlap with next change? Then include it
241 * in the current hunk and start over to find
242 * its new end.
243 */
244 if (xche->next) {
6f8d9bcc
RS
245 long l = XDL_MIN(xche->next->i1,
246 xe->xdf1.nrec - 1);
45d2f75f 247 if (l - xecfg->ctxlen <= e1 ||
14937c2c
RS
248 get_func_line(xe, xecfg, NULL, l, e1) < 0) {
249 xche = xche->next;
6d5badb2 250 goto post_context_calculation;
14937c2c
RS
251 }
252 }
253 }
254
3443546f
LT
255 /*
256 * Emit current hunk header.
257 */
acb72577
MW
258
259 if (xecfg->flags & XDL_EMIT_FUNCNAMES) {
f99f4b36
RS
260 get_func_line(xe, xecfg, &func_line,
261 s1 - 1, funclineprev);
c099789b 262 funclineprev = s1 - 1;
acb72577
MW
263 }
264 if (xdl_emit_hunk_hdr(s1 + 1, e1 - s1, s2 + 1, e2 - s2,
f99f4b36 265 func_line.buf, func_line.len, ecb) < 0)
3443546f
LT
266 return -1;
267
268 /*
269 * Emit pre-context.
270 */
baf5aaa3
RS
271 for (; s2 < xch->i2; s2++)
272 if (xdl_emit_record(&xe->xdf2, s2, " ", ecb) < 0)
3443546f
LT
273 return -1;
274
275 for (s1 = xch->i1, s2 = xch->i2;; xch = xch->next) {
276 /*
277 * Merge previous with current change atom.
278 */
279 for (; s1 < xch->i1 && s2 < xch->i2; s1++, s2++)
baf5aaa3 280 if (xdl_emit_record(&xe->xdf2, s2, " ", ecb) < 0)
3443546f
LT
281 return -1;
282
283 /*
284 * Removes lines from the first file.
285 */
286 for (s1 = xch->i1; s1 < xch->i1 + xch->chg1; s1++)
287 if (xdl_emit_record(&xe->xdf1, s1, "-", ecb) < 0)
288 return -1;
289
290 /*
291 * Adds lines from the second file.
292 */
293 for (s2 = xch->i2; s2 < xch->i2 + xch->chg2; s2++)
294 if (xdl_emit_record(&xe->xdf2, s2, "+", ecb) < 0)
295 return -1;
296
297 if (xch == xche)
298 break;
299 s1 = xch->i1 + xch->chg1;
300 s2 = xch->i2 + xch->chg2;
301 }
302
303 /*
304 * Emit post-context.
305 */
baf5aaa3
RS
306 for (s2 = xche->i2 + xche->chg2; s2 < e2; s2++)
307 if (xdl_emit_record(&xe->xdf2, s2, " ", ecb) < 0)
3443546f
LT
308 return -1;
309 }
310
311 return 0;
312}