Merge git://git.kernel.org/pub/scm/gitk/gitk into maint
[git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11
12 #ifdef NO_FAST_WORKING_DIRECTORY
13 #define FAST_WORKING_DIRECTORY 0
14 #else
15 #define FAST_WORKING_DIRECTORY 1
16 #endif
17
18 static int use_size_cache;
19
20 static int diff_detect_rename_default;
21 static int diff_rename_limit_default = -1;
22 static int diff_use_color_default;
23
24 static char diff_colors[][COLOR_MAXLEN] = {
25         "\033[m",       /* reset */
26         "",             /* PLAIN (normal) */
27         "\033[1m",      /* METAINFO (bold) */
28         "\033[36m",     /* FRAGINFO (cyan) */
29         "\033[31m",     /* OLD (red) */
30         "\033[32m",     /* NEW (green) */
31         "\033[33m",     /* COMMIT (yellow) */
32         "\033[41m",     /* WHITESPACE (red background) */
33 };
34
35 static int parse_diff_color_slot(const char *var, int ofs)
36 {
37         if (!strcasecmp(var+ofs, "plain"))
38                 return DIFF_PLAIN;
39         if (!strcasecmp(var+ofs, "meta"))
40                 return DIFF_METAINFO;
41         if (!strcasecmp(var+ofs, "frag"))
42                 return DIFF_FRAGINFO;
43         if (!strcasecmp(var+ofs, "old"))
44                 return DIFF_FILE_OLD;
45         if (!strcasecmp(var+ofs, "new"))
46                 return DIFF_FILE_NEW;
47         if (!strcasecmp(var+ofs, "commit"))
48                 return DIFF_COMMIT;
49         if (!strcasecmp(var+ofs, "whitespace"))
50                 return DIFF_WHITESPACE;
51         die("bad config variable '%s'", var);
52 }
53
54 /*
55  * These are to give UI layer defaults.
56  * The core-level commands such as git-diff-files should
57  * never be affected by the setting of diff.renames
58  * the user happens to have in the configuration file.
59  */
60 int git_diff_ui_config(const char *var, const char *value)
61 {
62         if (!strcmp(var, "diff.renamelimit")) {
63                 diff_rename_limit_default = git_config_int(var, value);
64                 return 0;
65         }
66         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
67                 diff_use_color_default = git_config_colorbool(var, value);
68                 return 0;
69         }
70         if (!strcmp(var, "diff.renames")) {
71                 if (!value)
72                         diff_detect_rename_default = DIFF_DETECT_RENAME;
73                 else if (!strcasecmp(value, "copies") ||
74                          !strcasecmp(value, "copy"))
75                         diff_detect_rename_default = DIFF_DETECT_COPY;
76                 else if (git_config_bool(var,value))
77                         diff_detect_rename_default = DIFF_DETECT_RENAME;
78                 return 0;
79         }
80         if (!strncmp(var, "diff.color.", 11) || !strncmp(var, "color.diff.", 11)) {
81                 int slot = parse_diff_color_slot(var, 11);
82                 color_parse(value, var, diff_colors[slot]);
83                 return 0;
84         }
85         return git_default_config(var, value);
86 }
87
88 static char *quote_one(const char *str)
89 {
90         int needlen;
91         char *xp;
92
93         if (!str)
94                 return NULL;
95         needlen = quote_c_style(str, NULL, NULL, 0);
96         if (!needlen)
97                 return xstrdup(str);
98         xp = xmalloc(needlen + 1);
99         quote_c_style(str, xp, NULL, 0);
100         return xp;
101 }
102
103 static char *quote_two(const char *one, const char *two)
104 {
105         int need_one = quote_c_style(one, NULL, NULL, 1);
106         int need_two = quote_c_style(two, NULL, NULL, 1);
107         char *xp;
108
109         if (need_one + need_two) {
110                 if (!need_one) need_one = strlen(one);
111                 if (!need_two) need_one = strlen(two);
112
113                 xp = xmalloc(need_one + need_two + 3);
114                 xp[0] = '"';
115                 quote_c_style(one, xp + 1, NULL, 1);
116                 quote_c_style(two, xp + need_one + 1, NULL, 1);
117                 strcpy(xp + need_one + need_two + 1, "\"");
118                 return xp;
119         }
120         need_one = strlen(one);
121         need_two = strlen(two);
122         xp = xmalloc(need_one + need_two + 1);
123         strcpy(xp, one);
124         strcpy(xp + need_one, two);
125         return xp;
126 }
127
128 static const char *external_diff(void)
129 {
130         static const char *external_diff_cmd = NULL;
131         static int done_preparing = 0;
132
133         if (done_preparing)
134                 return external_diff_cmd;
135         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
136         done_preparing = 1;
137         return external_diff_cmd;
138 }
139
140 #define TEMPFILE_PATH_LEN               50
141
142 static struct diff_tempfile {
143         const char *name; /* filename external diff should read from */
144         char hex[41];
145         char mode[10];
146         char tmp_path[TEMPFILE_PATH_LEN];
147 } diff_temp[2];
148
149 static int count_lines(const char *data, int size)
150 {
151         int count, ch, completely_empty = 1, nl_just_seen = 0;
152         count = 0;
153         while (0 < size--) {
154                 ch = *data++;
155                 if (ch == '\n') {
156                         count++;
157                         nl_just_seen = 1;
158                         completely_empty = 0;
159                 }
160                 else {
161                         nl_just_seen = 0;
162                         completely_empty = 0;
163                 }
164         }
165         if (completely_empty)
166                 return 0;
167         if (!nl_just_seen)
168                 count++; /* no trailing newline */
169         return count;
170 }
171
172 static void print_line_count(int count)
173 {
174         switch (count) {
175         case 0:
176                 printf("0,0");
177                 break;
178         case 1:
179                 printf("1");
180                 break;
181         default:
182                 printf("1,%d", count);
183                 break;
184         }
185 }
186
187 static void copy_file(int prefix, const char *data, int size)
188 {
189         int ch, nl_just_seen = 1;
190         while (0 < size--) {
191                 ch = *data++;
192                 if (nl_just_seen)
193                         putchar(prefix);
194                 putchar(ch);
195                 if (ch == '\n')
196                         nl_just_seen = 1;
197                 else
198                         nl_just_seen = 0;
199         }
200         if (!nl_just_seen)
201                 printf("\n\\ No newline at end of file\n");
202 }
203
204 static void emit_rewrite_diff(const char *name_a,
205                               const char *name_b,
206                               struct diff_filespec *one,
207                               struct diff_filespec *two)
208 {
209         int lc_a, lc_b;
210         diff_populate_filespec(one, 0);
211         diff_populate_filespec(two, 0);
212         lc_a = count_lines(one->data, one->size);
213         lc_b = count_lines(two->data, two->size);
214         printf("--- a/%s\n+++ b/%s\n@@ -", name_a, name_b);
215         print_line_count(lc_a);
216         printf(" +");
217         print_line_count(lc_b);
218         printf(" @@\n");
219         if (lc_a)
220                 copy_file('-', one->data, one->size);
221         if (lc_b)
222                 copy_file('+', two->data, two->size);
223 }
224
225 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
226 {
227         if (!DIFF_FILE_VALID(one)) {
228                 mf->ptr = (char *)""; /* does not matter */
229                 mf->size = 0;
230                 return 0;
231         }
232         else if (diff_populate_filespec(one, 0))
233                 return -1;
234         mf->ptr = one->data;
235         mf->size = one->size;
236         return 0;
237 }
238
239 struct diff_words_buffer {
240         mmfile_t text;
241         long alloc;
242         long current; /* output pointer */
243         int suppressed_newline;
244 };
245
246 static void diff_words_append(char *line, unsigned long len,
247                 struct diff_words_buffer *buffer)
248 {
249         if (buffer->text.size + len > buffer->alloc) {
250                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
251                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
252         }
253         line++;
254         len--;
255         memcpy(buffer->text.ptr + buffer->text.size, line, len);
256         buffer->text.size += len;
257 }
258
259 struct diff_words_data {
260         struct xdiff_emit_state xm;
261         struct diff_words_buffer minus, plus;
262 };
263
264 static void print_word(struct diff_words_buffer *buffer, int len, int color,
265                 int suppress_newline)
266 {
267         const char *ptr;
268         int eol = 0;
269
270         if (len == 0)
271                 return;
272
273         ptr  = buffer->text.ptr + buffer->current;
274         buffer->current += len;
275
276         if (ptr[len - 1] == '\n') {
277                 eol = 1;
278                 len--;
279         }
280
281         fputs(diff_get_color(1, color), stdout);
282         fwrite(ptr, len, 1, stdout);
283         fputs(diff_get_color(1, DIFF_RESET), stdout);
284
285         if (eol) {
286                 if (suppress_newline)
287                         buffer->suppressed_newline = 1;
288                 else
289                         putchar('\n');
290         }
291 }
292
293 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
294 {
295         struct diff_words_data *diff_words = priv;
296
297         if (diff_words->minus.suppressed_newline) {
298                 if (line[0] != '+')
299                         putchar('\n');
300                 diff_words->minus.suppressed_newline = 0;
301         }
302
303         len--;
304         switch (line[0]) {
305                 case '-':
306                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
307                         break;
308                 case '+':
309                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
310                         break;
311                 case ' ':
312                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
313                         diff_words->minus.current += len;
314                         break;
315         }
316 }
317
318 /* this executes the word diff on the accumulated buffers */
319 static void diff_words_show(struct diff_words_data *diff_words)
320 {
321         xpparam_t xpp;
322         xdemitconf_t xecfg;
323         xdemitcb_t ecb;
324         mmfile_t minus, plus;
325         int i;
326
327         minus.size = diff_words->minus.text.size;
328         minus.ptr = xmalloc(minus.size);
329         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
330         for (i = 0; i < minus.size; i++)
331                 if (isspace(minus.ptr[i]))
332                         minus.ptr[i] = '\n';
333         diff_words->minus.current = 0;
334
335         plus.size = diff_words->plus.text.size;
336         plus.ptr = xmalloc(plus.size);
337         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
338         for (i = 0; i < plus.size; i++)
339                 if (isspace(plus.ptr[i]))
340                         plus.ptr[i] = '\n';
341         diff_words->plus.current = 0;
342
343         xpp.flags = XDF_NEED_MINIMAL;
344         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
345         xecfg.flags = 0;
346         ecb.outf = xdiff_outf;
347         ecb.priv = diff_words;
348         diff_words->xm.consume = fn_out_diff_words_aux;
349         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
350
351         free(minus.ptr);
352         free(plus.ptr);
353         diff_words->minus.text.size = diff_words->plus.text.size = 0;
354
355         if (diff_words->minus.suppressed_newline) {
356                 putchar('\n');
357                 diff_words->minus.suppressed_newline = 0;
358         }
359 }
360
361 struct emit_callback {
362         struct xdiff_emit_state xm;
363         int nparents, color_diff;
364         const char **label_path;
365         struct diff_words_data *diff_words;
366 };
367
368 static void free_diff_words_data(struct emit_callback *ecbdata)
369 {
370         if (ecbdata->diff_words) {
371                 /* flush buffers */
372                 if (ecbdata->diff_words->minus.text.size ||
373                                 ecbdata->diff_words->plus.text.size)
374                         diff_words_show(ecbdata->diff_words);
375
376                 if (ecbdata->diff_words->minus.text.ptr)
377                         free (ecbdata->diff_words->minus.text.ptr);
378                 if (ecbdata->diff_words->plus.text.ptr)
379                         free (ecbdata->diff_words->plus.text.ptr);
380                 free(ecbdata->diff_words);
381                 ecbdata->diff_words = NULL;
382         }
383 }
384
385 const char *diff_get_color(int diff_use_color, enum color_diff ix)
386 {
387         if (diff_use_color)
388                 return diff_colors[ix];
389         return "";
390 }
391
392 static void emit_line(const char *set, const char *reset, const char *line, int len)
393 {
394         if (len > 0 && line[len-1] == '\n')
395                 len--;
396         fputs(set, stdout);
397         fwrite(line, len, 1, stdout);
398         puts(reset);
399 }
400
401 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
402 {
403         int col0 = ecbdata->nparents;
404         int last_tab_in_indent = -1;
405         int last_space_in_indent = -1;
406         int i;
407         int tail = len;
408         int need_highlight_leading_space = 0;
409         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
410         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
411
412         if (!*ws) {
413                 emit_line(set, reset, line, len);
414                 return;
415         }
416
417         /* The line is a newly added line.  Does it have funny leading
418          * whitespaces?  In indent, SP should never precede a TAB.
419          */
420         for (i = col0; i < len; i++) {
421                 if (line[i] == '\t') {
422                         last_tab_in_indent = i;
423                         if (0 <= last_space_in_indent)
424                                 need_highlight_leading_space = 1;
425                 }
426                 else if (line[i] == ' ')
427                         last_space_in_indent = i;
428                 else
429                         break;
430         }
431         fputs(set, stdout);
432         fwrite(line, col0, 1, stdout);
433         fputs(reset, stdout);
434         if (((i == len) || line[i] == '\n') && i != col0) {
435                 /* The whole line was indent */
436                 emit_line(ws, reset, line + col0, len - col0);
437                 return;
438         }
439         i = col0;
440         if (need_highlight_leading_space) {
441                 while (i < last_tab_in_indent) {
442                         if (line[i] == ' ') {
443                                 fputs(ws, stdout);
444                                 putchar(' ');
445                                 fputs(reset, stdout);
446                         }
447                         else
448                                 putchar(line[i]);
449                         i++;
450                 }
451         }
452         tail = len - 1;
453         if (line[tail] == '\n' && i < tail)
454                 tail--;
455         while (i < tail) {
456                 if (!isspace(line[tail]))
457                         break;
458                 tail--;
459         }
460         if ((i < tail && line[tail + 1] != '\n')) {
461                 /* This has whitespace between tail+1..len */
462                 fputs(set, stdout);
463                 fwrite(line + i, tail - i + 1, 1, stdout);
464                 fputs(reset, stdout);
465                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
466         }
467         else
468                 emit_line(set, reset, line + i, len - i);
469 }
470
471 static void fn_out_consume(void *priv, char *line, unsigned long len)
472 {
473         int i;
474         int color;
475         struct emit_callback *ecbdata = priv;
476         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
477         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
478
479         if (ecbdata->label_path[0]) {
480                 printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
481                 printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
482                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
483         }
484
485         /* This is not really necessary for now because
486          * this codepath only deals with two-way diffs.
487          */
488         for (i = 0; i < len && line[i] == '@'; i++)
489                 ;
490         if (2 <= i && i < len && line[i] == ' ') {
491                 ecbdata->nparents = i - 1;
492                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
493                           reset, line, len);
494                 return;
495         }
496
497         if (len < ecbdata->nparents) {
498                 set = reset;
499                 emit_line(reset, reset, line, len);
500                 return;
501         }
502
503         color = DIFF_PLAIN;
504         if (ecbdata->diff_words && ecbdata->nparents != 1)
505                 /* fall back to normal diff */
506                 free_diff_words_data(ecbdata);
507         if (ecbdata->diff_words) {
508                 if (line[0] == '-') {
509                         diff_words_append(line, len,
510                                           &ecbdata->diff_words->minus);
511                         return;
512                 } else if (line[0] == '+') {
513                         diff_words_append(line, len,
514                                           &ecbdata->diff_words->plus);
515                         return;
516                 }
517                 if (ecbdata->diff_words->minus.text.size ||
518                     ecbdata->diff_words->plus.text.size)
519                         diff_words_show(ecbdata->diff_words);
520                 line++;
521                 len--;
522                 emit_line(set, reset, line, len);
523                 return;
524         }
525         for (i = 0; i < ecbdata->nparents && len; i++) {
526                 if (line[i] == '-')
527                         color = DIFF_FILE_OLD;
528                 else if (line[i] == '+')
529                         color = DIFF_FILE_NEW;
530         }
531
532         if (color != DIFF_FILE_NEW) {
533                 emit_line(diff_get_color(ecbdata->color_diff, color),
534                           reset, line, len);
535                 return;
536         }
537         emit_add_line(reset, ecbdata, line, len);
538 }
539
540 static char *pprint_rename(const char *a, const char *b)
541 {
542         const char *old = a;
543         const char *new = b;
544         char *name = NULL;
545         int pfx_length, sfx_length;
546         int len_a = strlen(a);
547         int len_b = strlen(b);
548         int qlen_a = quote_c_style(a, NULL, NULL, 0);
549         int qlen_b = quote_c_style(b, NULL, NULL, 0);
550
551         if (qlen_a || qlen_b) {
552                 if (qlen_a) len_a = qlen_a;
553                 if (qlen_b) len_b = qlen_b;
554                 name = xmalloc( len_a + len_b + 5 );
555                 if (qlen_a)
556                         quote_c_style(a, name, NULL, 0);
557                 else
558                         memcpy(name, a, len_a);
559                 memcpy(name + len_a, " => ", 4);
560                 if (qlen_b)
561                         quote_c_style(b, name + len_a + 4, NULL, 0);
562                 else
563                         memcpy(name + len_a + 4, b, len_b + 1);
564                 return name;
565         }
566
567         /* Find common prefix */
568         pfx_length = 0;
569         while (*old && *new && *old == *new) {
570                 if (*old == '/')
571                         pfx_length = old - a + 1;
572                 old++;
573                 new++;
574         }
575
576         /* Find common suffix */
577         old = a + len_a;
578         new = b + len_b;
579         sfx_length = 0;
580         while (a <= old && b <= new && *old == *new) {
581                 if (*old == '/')
582                         sfx_length = len_a - (old - a);
583                 old--;
584                 new--;
585         }
586
587         /*
588          * pfx{mid-a => mid-b}sfx
589          * {pfx-a => pfx-b}sfx
590          * pfx{sfx-a => sfx-b}
591          * name-a => name-b
592          */
593         if (pfx_length + sfx_length) {
594                 int a_midlen = len_a - pfx_length - sfx_length;
595                 int b_midlen = len_b - pfx_length - sfx_length;
596                 if (a_midlen < 0) a_midlen = 0;
597                 if (b_midlen < 0) b_midlen = 0;
598
599                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
600                 sprintf(name, "%.*s{%.*s => %.*s}%s",
601                         pfx_length, a,
602                         a_midlen, a + pfx_length,
603                         b_midlen, b + pfx_length,
604                         a + len_a - sfx_length);
605         }
606         else {
607                 name = xmalloc(len_a + len_b + 5);
608                 sprintf(name, "%s => %s", a, b);
609         }
610         return name;
611 }
612
613 struct diffstat_t {
614         struct xdiff_emit_state xm;
615
616         int nr;
617         int alloc;
618         struct diffstat_file {
619                 char *name;
620                 unsigned is_unmerged:1;
621                 unsigned is_binary:1;
622                 unsigned is_renamed:1;
623                 unsigned int added, deleted;
624         } **files;
625 };
626
627 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
628                                           const char *name_a,
629                                           const char *name_b)
630 {
631         struct diffstat_file *x;
632         x = xcalloc(sizeof (*x), 1);
633         if (diffstat->nr == diffstat->alloc) {
634                 diffstat->alloc = alloc_nr(diffstat->alloc);
635                 diffstat->files = xrealloc(diffstat->files,
636                                 diffstat->alloc * sizeof(x));
637         }
638         diffstat->files[diffstat->nr++] = x;
639         if (name_b) {
640                 x->name = pprint_rename(name_a, name_b);
641                 x->is_renamed = 1;
642         }
643         else
644                 x->name = xstrdup(name_a);
645         return x;
646 }
647
648 static void diffstat_consume(void *priv, char *line, unsigned long len)
649 {
650         struct diffstat_t *diffstat = priv;
651         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
652
653         if (line[0] == '+')
654                 x->added++;
655         else if (line[0] == '-')
656                 x->deleted++;
657 }
658
659 const char mime_boundary_leader[] = "------------";
660
661 static int scale_linear(int it, int width, int max_change)
662 {
663         /*
664          * make sure that at least one '-' is printed if there were deletions,
665          * and likewise for '+'.
666          */
667         if (max_change < 2)
668                 return it;
669         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
670 }
671
672 static void show_name(const char *prefix, const char *name, int len,
673                       const char *reset, const char *set)
674 {
675         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
676 }
677
678 static void show_graph(char ch, int cnt, const char *set, const char *reset)
679 {
680         if (cnt <= 0)
681                 return;
682         printf("%s", set);
683         while (cnt--)
684                 putchar(ch);
685         printf("%s", reset);
686 }
687
688 static void show_stats(struct diffstat_t* data, struct diff_options *options)
689 {
690         int i, len, add, del, total, adds = 0, dels = 0;
691         int max_change = 0, max_len = 0;
692         int total_files = data->nr;
693         int width, name_width;
694         const char *reset, *set, *add_c, *del_c;
695
696         if (data->nr == 0)
697                 return;
698
699         width = options->stat_width ? options->stat_width : 80;
700         name_width = options->stat_name_width ? options->stat_name_width : 50;
701
702         /* Sanity: give at least 5 columns to the graph,
703          * but leave at least 10 columns for the name.
704          */
705         if (width < name_width + 15) {
706                 if (name_width <= 25)
707                         width = name_width + 15;
708                 else
709                         name_width = width - 15;
710         }
711
712         /* Find the longest filename and max number of changes */
713         reset = diff_get_color(options->color_diff, DIFF_RESET);
714         set = diff_get_color(options->color_diff, DIFF_PLAIN);
715         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
716         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
717
718         for (i = 0; i < data->nr; i++) {
719                 struct diffstat_file *file = data->files[i];
720                 int change = file->added + file->deleted;
721
722                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
723                         len = quote_c_style(file->name, NULL, NULL, 0);
724                         if (len) {
725                                 char *qname = xmalloc(len + 1);
726                                 quote_c_style(file->name, qname, NULL, 0);
727                                 free(file->name);
728                                 file->name = qname;
729                         }
730                 }
731
732                 len = strlen(file->name);
733                 if (max_len < len)
734                         max_len = len;
735
736                 if (file->is_binary || file->is_unmerged)
737                         continue;
738                 if (max_change < change)
739                         max_change = change;
740         }
741
742         /* Compute the width of the graph part;
743          * 10 is for one blank at the beginning of the line plus
744          * " | count " between the name and the graph.
745          *
746          * From here on, name_width is the width of the name area,
747          * and width is the width of the graph area.
748          */
749         name_width = (name_width < max_len) ? name_width : max_len;
750         if (width < (name_width + 10) + max_change)
751                 width = width - (name_width + 10);
752         else
753                 width = max_change;
754
755         for (i = 0; i < data->nr; i++) {
756                 const char *prefix = "";
757                 char *name = data->files[i]->name;
758                 int added = data->files[i]->added;
759                 int deleted = data->files[i]->deleted;
760                 int name_len;
761
762                 /*
763                  * "scale" the filename
764                  */
765                 len = name_width;
766                 name_len = strlen(name);
767                 if (name_width < name_len) {
768                         char *slash;
769                         prefix = "...";
770                         len -= 3;
771                         name += name_len - len;
772                         slash = strchr(name, '/');
773                         if (slash)
774                                 name = slash;
775                 }
776
777                 if (data->files[i]->is_binary) {
778                         show_name(prefix, name, len, reset, set);
779                         printf("  Bin\n");
780                         goto free_diffstat_file;
781                 }
782                 else if (data->files[i]->is_unmerged) {
783                         show_name(prefix, name, len, reset, set);
784                         printf("  Unmerged\n");
785                         goto free_diffstat_file;
786                 }
787                 else if (!data->files[i]->is_renamed &&
788                          (added + deleted == 0)) {
789                         total_files--;
790                         goto free_diffstat_file;
791                 }
792
793                 /*
794                  * scale the add/delete
795                  */
796                 add = added;
797                 del = deleted;
798                 total = add + del;
799                 adds += add;
800                 dels += del;
801
802                 if (width <= max_change) {
803                         add = scale_linear(add, width, max_change);
804                         del = scale_linear(del, width, max_change);
805                         total = add + del;
806                 }
807                 show_name(prefix, name, len, reset, set);
808                 printf("%5d ", added + deleted);
809                 show_graph('+', add, add_c, reset);
810                 show_graph('-', del, del_c, reset);
811                 putchar('\n');
812         free_diffstat_file:
813                 free(data->files[i]->name);
814                 free(data->files[i]);
815         }
816         free(data->files);
817         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
818                set, total_files, adds, dels, reset);
819 }
820
821 static void show_shortstats(struct diffstat_t* data)
822 {
823         int i, adds = 0, dels = 0, total_files = data->nr;
824
825         if (data->nr == 0)
826                 return;
827
828         for (i = 0; i < data->nr; i++) {
829                 if (!data->files[i]->is_binary &&
830                     !data->files[i]->is_unmerged) {
831                         int added = data->files[i]->added;
832                         int deleted= data->files[i]->deleted;
833                         if (!data->files[i]->is_renamed &&
834                             (added + deleted == 0)) {
835                                 total_files--;
836                         } else {
837                                 adds += added;
838                                 dels += deleted;
839                         }
840                 }
841                 free(data->files[i]->name);
842                 free(data->files[i]);
843         }
844         free(data->files);
845
846         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
847                total_files, adds, dels);
848 }
849
850 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
851 {
852         int i;
853
854         for (i = 0; i < data->nr; i++) {
855                 struct diffstat_file *file = data->files[i];
856
857                 if (file->is_binary)
858                         printf("-\t-\t");
859                 else
860                         printf("%d\t%d\t", file->added, file->deleted);
861                 if (options->line_termination && !file->is_renamed &&
862                     quote_c_style(file->name, NULL, NULL, 0))
863                         quote_c_style(file->name, NULL, stdout, 0);
864                 else
865                         fputs(file->name, stdout);
866                 putchar(options->line_termination);
867         }
868 }
869
870 struct checkdiff_t {
871         struct xdiff_emit_state xm;
872         const char *filename;
873         int lineno;
874 };
875
876 static void checkdiff_consume(void *priv, char *line, unsigned long len)
877 {
878         struct checkdiff_t *data = priv;
879
880         if (line[0] == '+') {
881                 int i, spaces = 0;
882
883                 /* check space before tab */
884                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
885                         if (line[i] == ' ')
886                                 spaces++;
887                 if (line[i - 1] == '\t' && spaces)
888                         printf("%s:%d: space before tab:%.*s\n",
889                                 data->filename, data->lineno, (int)len, line);
890
891                 /* check white space at line end */
892                 if (line[len - 1] == '\n')
893                         len--;
894                 if (isspace(line[len - 1]))
895                         printf("%s:%d: white space at end: %.*s\n",
896                                 data->filename, data->lineno, (int)len, line);
897
898                 data->lineno++;
899         } else if (line[0] == ' ')
900                 data->lineno++;
901         else if (line[0] == '@') {
902                 char *plus = strchr(line, '+');
903                 if (plus)
904                         data->lineno = strtol(plus, NULL, 10);
905                 else
906                         die("invalid diff");
907         }
908 }
909
910 static unsigned char *deflate_it(char *data,
911                                  unsigned long size,
912                                  unsigned long *result_size)
913 {
914         int bound;
915         unsigned char *deflated;
916         z_stream stream;
917
918         memset(&stream, 0, sizeof(stream));
919         deflateInit(&stream, zlib_compression_level);
920         bound = deflateBound(&stream, size);
921         deflated = xmalloc(bound);
922         stream.next_out = deflated;
923         stream.avail_out = bound;
924
925         stream.next_in = (unsigned char *)data;
926         stream.avail_in = size;
927         while (deflate(&stream, Z_FINISH) == Z_OK)
928                 ; /* nothing */
929         deflateEnd(&stream);
930         *result_size = stream.total_out;
931         return deflated;
932 }
933
934 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
935 {
936         void *cp;
937         void *delta;
938         void *deflated;
939         void *data;
940         unsigned long orig_size;
941         unsigned long delta_size;
942         unsigned long deflate_size;
943         unsigned long data_size;
944
945         /* We could do deflated delta, or we could do just deflated two,
946          * whichever is smaller.
947          */
948         delta = NULL;
949         deflated = deflate_it(two->ptr, two->size, &deflate_size);
950         if (one->size && two->size) {
951                 delta = diff_delta(one->ptr, one->size,
952                                    two->ptr, two->size,
953                                    &delta_size, deflate_size);
954                 if (delta) {
955                         void *to_free = delta;
956                         orig_size = delta_size;
957                         delta = deflate_it(delta, delta_size, &delta_size);
958                         free(to_free);
959                 }
960         }
961
962         if (delta && delta_size < deflate_size) {
963                 printf("delta %lu\n", orig_size);
964                 free(deflated);
965                 data = delta;
966                 data_size = delta_size;
967         }
968         else {
969                 printf("literal %lu\n", two->size);
970                 free(delta);
971                 data = deflated;
972                 data_size = deflate_size;
973         }
974
975         /* emit data encoded in base85 */
976         cp = data;
977         while (data_size) {
978                 int bytes = (52 < data_size) ? 52 : data_size;
979                 char line[70];
980                 data_size -= bytes;
981                 if (bytes <= 26)
982                         line[0] = bytes + 'A' - 1;
983                 else
984                         line[0] = bytes - 26 + 'a' - 1;
985                 encode_85(line + 1, cp, bytes);
986                 cp = (char *) cp + bytes;
987                 puts(line);
988         }
989         printf("\n");
990         free(data);
991 }
992
993 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
994 {
995         printf("GIT binary patch\n");
996         emit_binary_diff_body(one, two);
997         emit_binary_diff_body(two, one);
998 }
999
1000 #define FIRST_FEW_BYTES 8000
1001 static int mmfile_is_binary(mmfile_t *mf)
1002 {
1003         long sz = mf->size;
1004         if (FIRST_FEW_BYTES < sz)
1005                 sz = FIRST_FEW_BYTES;
1006         return !!memchr(mf->ptr, 0, sz);
1007 }
1008
1009 static void builtin_diff(const char *name_a,
1010                          const char *name_b,
1011                          struct diff_filespec *one,
1012                          struct diff_filespec *two,
1013                          const char *xfrm_msg,
1014                          struct diff_options *o,
1015                          int complete_rewrite)
1016 {
1017         mmfile_t mf1, mf2;
1018         const char *lbl[2];
1019         char *a_one, *b_two;
1020         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
1021         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
1022
1023         a_one = quote_two("a/", name_a);
1024         b_two = quote_two("b/", name_b);
1025         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1026         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1027         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1028         if (lbl[0][0] == '/') {
1029                 /* /dev/null */
1030                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1031                 if (xfrm_msg && xfrm_msg[0])
1032                         printf("%s%s%s\n", set, xfrm_msg, reset);
1033         }
1034         else if (lbl[1][0] == '/') {
1035                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1036                 if (xfrm_msg && xfrm_msg[0])
1037                         printf("%s%s%s\n", set, xfrm_msg, reset);
1038         }
1039         else {
1040                 if (one->mode != two->mode) {
1041                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1042                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1043                 }
1044                 if (xfrm_msg && xfrm_msg[0])
1045                         printf("%s%s%s\n", set, xfrm_msg, reset);
1046                 /*
1047                  * we do not run diff between different kind
1048                  * of objects.
1049                  */
1050                 if ((one->mode ^ two->mode) & S_IFMT)
1051                         goto free_ab_and_return;
1052                 if (complete_rewrite) {
1053                         emit_rewrite_diff(name_a, name_b, one, two);
1054                         goto free_ab_and_return;
1055                 }
1056         }
1057
1058         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1059                 die("unable to read files to diff");
1060
1061         if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
1062                 /* Quite common confusing case */
1063                 if (mf1.size == mf2.size &&
1064                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1065                         goto free_ab_and_return;
1066                 if (o->binary)
1067                         emit_binary_diff(&mf1, &mf2);
1068                 else
1069                         printf("Binary files %s and %s differ\n",
1070                                lbl[0], lbl[1]);
1071         }
1072         else {
1073                 /* Crazy xdl interfaces.. */
1074                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1075                 xpparam_t xpp;
1076                 xdemitconf_t xecfg;
1077                 xdemitcb_t ecb;
1078                 struct emit_callback ecbdata;
1079
1080                 memset(&ecbdata, 0, sizeof(ecbdata));
1081                 ecbdata.label_path = lbl;
1082                 ecbdata.color_diff = o->color_diff;
1083                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1084                 xecfg.ctxlen = o->context;
1085                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1086                 if (!diffopts)
1087                         ;
1088                 else if (!strncmp(diffopts, "--unified=", 10))
1089                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1090                 else if (!strncmp(diffopts, "-u", 2))
1091                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1092                 ecb.outf = xdiff_outf;
1093                 ecb.priv = &ecbdata;
1094                 ecbdata.xm.consume = fn_out_consume;
1095                 if (o->color_diff_words)
1096                         ecbdata.diff_words =
1097                                 xcalloc(1, sizeof(struct diff_words_data));
1098                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1099                 if (o->color_diff_words)
1100                         free_diff_words_data(&ecbdata);
1101         }
1102
1103  free_ab_and_return:
1104         free(a_one);
1105         free(b_two);
1106         return;
1107 }
1108
1109 static void builtin_diffstat(const char *name_a, const char *name_b,
1110                              struct diff_filespec *one,
1111                              struct diff_filespec *two,
1112                              struct diffstat_t *diffstat,
1113                              struct diff_options *o,
1114                              int complete_rewrite)
1115 {
1116         mmfile_t mf1, mf2;
1117         struct diffstat_file *data;
1118
1119         data = diffstat_add(diffstat, name_a, name_b);
1120
1121         if (!one || !two) {
1122                 data->is_unmerged = 1;
1123                 return;
1124         }
1125         if (complete_rewrite) {
1126                 diff_populate_filespec(one, 0);
1127                 diff_populate_filespec(two, 0);
1128                 data->deleted = count_lines(one->data, one->size);
1129                 data->added = count_lines(two->data, two->size);
1130                 return;
1131         }
1132         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1133                 die("unable to read files to diff");
1134
1135         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
1136                 data->is_binary = 1;
1137         else {
1138                 /* Crazy xdl interfaces.. */
1139                 xpparam_t xpp;
1140                 xdemitconf_t xecfg;
1141                 xdemitcb_t ecb;
1142
1143                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1144                 xecfg.ctxlen = 0;
1145                 xecfg.flags = 0;
1146                 ecb.outf = xdiff_outf;
1147                 ecb.priv = diffstat;
1148                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1149         }
1150 }
1151
1152 static void builtin_checkdiff(const char *name_a, const char *name_b,
1153                              struct diff_filespec *one,
1154                              struct diff_filespec *two)
1155 {
1156         mmfile_t mf1, mf2;
1157         struct checkdiff_t data;
1158
1159         if (!two)
1160                 return;
1161
1162         memset(&data, 0, sizeof(data));
1163         data.xm.consume = checkdiff_consume;
1164         data.filename = name_b ? name_b : name_a;
1165         data.lineno = 0;
1166
1167         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1168                 die("unable to read files to diff");
1169
1170         if (mmfile_is_binary(&mf2))
1171                 return;
1172         else {
1173                 /* Crazy xdl interfaces.. */
1174                 xpparam_t xpp;
1175                 xdemitconf_t xecfg;
1176                 xdemitcb_t ecb;
1177
1178                 xpp.flags = XDF_NEED_MINIMAL;
1179                 xecfg.ctxlen = 0;
1180                 xecfg.flags = 0;
1181                 ecb.outf = xdiff_outf;
1182                 ecb.priv = &data;
1183                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1184         }
1185 }
1186
1187 struct diff_filespec *alloc_filespec(const char *path)
1188 {
1189         int namelen = strlen(path);
1190         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1191
1192         memset(spec, 0, sizeof(*spec));
1193         spec->path = (char *)(spec + 1);
1194         memcpy(spec->path, path, namelen+1);
1195         return spec;
1196 }
1197
1198 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1199                    unsigned short mode)
1200 {
1201         if (mode) {
1202                 spec->mode = canon_mode(mode);
1203                 hashcpy(spec->sha1, sha1);
1204                 spec->sha1_valid = !is_null_sha1(sha1);
1205         }
1206 }
1207
1208 /*
1209  * Given a name and sha1 pair, if the dircache tells us the file in
1210  * the work tree has that object contents, return true, so that
1211  * prepare_temp_file() does not have to inflate and extract.
1212  */
1213 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1214 {
1215         struct cache_entry *ce;
1216         struct stat st;
1217         int pos, len;
1218
1219         /* We do not read the cache ourselves here, because the
1220          * benchmark with my previous version that always reads cache
1221          * shows that it makes things worse for diff-tree comparing
1222          * two linux-2.6 kernel trees in an already checked out work
1223          * tree.  This is because most diff-tree comparisons deal with
1224          * only a small number of files, while reading the cache is
1225          * expensive for a large project, and its cost outweighs the
1226          * savings we get by not inflating the object to a temporary
1227          * file.  Practically, this code only helps when we are used
1228          * by diff-cache --cached, which does read the cache before
1229          * calling us.
1230          */
1231         if (!active_cache)
1232                 return 0;
1233
1234         /* We want to avoid the working directory if our caller
1235          * doesn't need the data in a normal file, this system
1236          * is rather slow with its stat/open/mmap/close syscalls,
1237          * and the object is contained in a pack file.  The pack
1238          * is probably already open and will be faster to obtain
1239          * the data through than the working directory.  Loose
1240          * objects however would tend to be slower as they need
1241          * to be individually opened and inflated.
1242          */
1243         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1244                 return 0;
1245
1246         len = strlen(name);
1247         pos = cache_name_pos(name, len);
1248         if (pos < 0)
1249                 return 0;
1250         ce = active_cache[pos];
1251         if ((lstat(name, &st) < 0) ||
1252             !S_ISREG(st.st_mode) || /* careful! */
1253             ce_match_stat(ce, &st, 0) ||
1254             hashcmp(sha1, ce->sha1))
1255                 return 0;
1256         /* we return 1 only when we can stat, it is a regular file,
1257          * stat information matches, and sha1 recorded in the cache
1258          * matches.  I.e. we know the file in the work tree really is
1259          * the same as the <name, sha1> pair.
1260          */
1261         return 1;
1262 }
1263
1264 static struct sha1_size_cache {
1265         unsigned char sha1[20];
1266         unsigned long size;
1267 } **sha1_size_cache;
1268 static int sha1_size_cache_nr, sha1_size_cache_alloc;
1269
1270 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
1271                                                  int find_only,
1272                                                  unsigned long size)
1273 {
1274         int first, last;
1275         struct sha1_size_cache *e;
1276
1277         first = 0;
1278         last = sha1_size_cache_nr;
1279         while (last > first) {
1280                 int cmp, next = (last + first) >> 1;
1281                 e = sha1_size_cache[next];
1282                 cmp = hashcmp(e->sha1, sha1);
1283                 if (!cmp)
1284                         return e;
1285                 if (cmp < 0) {
1286                         last = next;
1287                         continue;
1288                 }
1289                 first = next+1;
1290         }
1291         /* not found */
1292         if (find_only)
1293                 return NULL;
1294         /* insert to make it at "first" */
1295         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
1296                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
1297                 sha1_size_cache = xrealloc(sha1_size_cache,
1298                                            sha1_size_cache_alloc *
1299                                            sizeof(*sha1_size_cache));
1300         }
1301         sha1_size_cache_nr++;
1302         if (first < sha1_size_cache_nr)
1303                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
1304                         (sha1_size_cache_nr - first - 1) *
1305                         sizeof(*sha1_size_cache));
1306         e = xmalloc(sizeof(struct sha1_size_cache));
1307         sha1_size_cache[first] = e;
1308         hashcpy(e->sha1, sha1);
1309         e->size = size;
1310         return e;
1311 }
1312
1313 /*
1314  * While doing rename detection and pickaxe operation, we may need to
1315  * grab the data for the blob (or file) for our own in-core comparison.
1316  * diff_filespec has data and size fields for this purpose.
1317  */
1318 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1319 {
1320         int err = 0;
1321         if (!DIFF_FILE_VALID(s))
1322                 die("internal error: asking to populate invalid file.");
1323         if (S_ISDIR(s->mode))
1324                 return -1;
1325
1326         if (!use_size_cache)
1327                 size_only = 0;
1328
1329         if (s->data)
1330                 return err;
1331         if (!s->sha1_valid ||
1332             reuse_worktree_file(s->path, s->sha1, 0)) {
1333                 struct stat st;
1334                 int fd;
1335                 if (lstat(s->path, &st) < 0) {
1336                         if (errno == ENOENT) {
1337                         err_empty:
1338                                 err = -1;
1339                         empty:
1340                                 s->data = (char *)"";
1341                                 s->size = 0;
1342                                 return err;
1343                         }
1344                 }
1345                 s->size = st.st_size;
1346                 if (!s->size)
1347                         goto empty;
1348                 if (size_only)
1349                         return 0;
1350                 if (S_ISLNK(st.st_mode)) {
1351                         int ret;
1352                         s->data = xmalloc(s->size);
1353                         s->should_free = 1;
1354                         ret = readlink(s->path, s->data, s->size);
1355                         if (ret < 0) {
1356                                 free(s->data);
1357                                 goto err_empty;
1358                         }
1359                         return 0;
1360                 }
1361                 fd = open(s->path, O_RDONLY);
1362                 if (fd < 0)
1363                         goto err_empty;
1364                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1365                 close(fd);
1366                 s->should_munmap = 1;
1367                 /* FIXME! CRLF -> LF conversion goes here, based on "s->path" */
1368         }
1369         else {
1370                 char type[20];
1371                 struct sha1_size_cache *e;
1372
1373                 if (size_only) {
1374                         e = locate_size_cache(s->sha1, 1, 0);
1375                         if (e) {
1376                                 s->size = e->size;
1377                                 return 0;
1378                         }
1379                         if (!sha1_object_info(s->sha1, type, &s->size))
1380                                 locate_size_cache(s->sha1, 0, s->size);
1381                 }
1382                 else {
1383                         s->data = read_sha1_file(s->sha1, type, &s->size);
1384                         s->should_free = 1;
1385                 }
1386         }
1387         return 0;
1388 }
1389
1390 void diff_free_filespec_data(struct diff_filespec *s)
1391 {
1392         if (s->should_free)
1393                 free(s->data);
1394         else if (s->should_munmap)
1395                 munmap(s->data, s->size);
1396         s->should_free = s->should_munmap = 0;
1397         s->data = NULL;
1398         free(s->cnt_data);
1399         s->cnt_data = NULL;
1400 }
1401
1402 static void prep_temp_blob(struct diff_tempfile *temp,
1403                            void *blob,
1404                            unsigned long size,
1405                            const unsigned char *sha1,
1406                            int mode)
1407 {
1408         int fd;
1409
1410         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1411         if (fd < 0)
1412                 die("unable to create temp-file");
1413         if (write_in_full(fd, blob, size) != size)
1414                 die("unable to write temp-file");
1415         close(fd);
1416         temp->name = temp->tmp_path;
1417         strcpy(temp->hex, sha1_to_hex(sha1));
1418         temp->hex[40] = 0;
1419         sprintf(temp->mode, "%06o", mode);
1420 }
1421
1422 static void prepare_temp_file(const char *name,
1423                               struct diff_tempfile *temp,
1424                               struct diff_filespec *one)
1425 {
1426         if (!DIFF_FILE_VALID(one)) {
1427         not_a_valid_file:
1428                 /* A '-' entry produces this for file-2, and
1429                  * a '+' entry produces this for file-1.
1430                  */
1431                 temp->name = "/dev/null";
1432                 strcpy(temp->hex, ".");
1433                 strcpy(temp->mode, ".");
1434                 return;
1435         }
1436
1437         if (!one->sha1_valid ||
1438             reuse_worktree_file(name, one->sha1, 1)) {
1439                 struct stat st;
1440                 if (lstat(name, &st) < 0) {
1441                         if (errno == ENOENT)
1442                                 goto not_a_valid_file;
1443                         die("stat(%s): %s", name, strerror(errno));
1444                 }
1445                 if (S_ISLNK(st.st_mode)) {
1446                         int ret;
1447                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1448                         if (sizeof(buf) <= st.st_size)
1449                                 die("symlink too long: %s", name);
1450                         ret = readlink(name, buf, st.st_size);
1451                         if (ret < 0)
1452                                 die("readlink(%s)", name);
1453                         prep_temp_blob(temp, buf, st.st_size,
1454                                        (one->sha1_valid ?
1455                                         one->sha1 : null_sha1),
1456                                        (one->sha1_valid ?
1457                                         one->mode : S_IFLNK));
1458                 }
1459                 else {
1460                         /* we can borrow from the file in the work tree */
1461                         temp->name = name;
1462                         if (!one->sha1_valid)
1463                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1464                         else
1465                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1466                         /* Even though we may sometimes borrow the
1467                          * contents from the work tree, we always want
1468                          * one->mode.  mode is trustworthy even when
1469                          * !(one->sha1_valid), as long as
1470                          * DIFF_FILE_VALID(one).
1471                          */
1472                         sprintf(temp->mode, "%06o", one->mode);
1473                 }
1474                 return;
1475         }
1476         else {
1477                 if (diff_populate_filespec(one, 0))
1478                         die("cannot read data blob for %s", one->path);
1479                 prep_temp_blob(temp, one->data, one->size,
1480                                one->sha1, one->mode);
1481         }
1482 }
1483
1484 static void remove_tempfile(void)
1485 {
1486         int i;
1487
1488         for (i = 0; i < 2; i++)
1489                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1490                         unlink(diff_temp[i].name);
1491                         diff_temp[i].name = NULL;
1492                 }
1493 }
1494
1495 static void remove_tempfile_on_signal(int signo)
1496 {
1497         remove_tempfile();
1498         signal(SIGINT, SIG_DFL);
1499         raise(signo);
1500 }
1501
1502 static int spawn_prog(const char *pgm, const char **arg)
1503 {
1504         pid_t pid;
1505         int status;
1506
1507         fflush(NULL);
1508         pid = fork();
1509         if (pid < 0)
1510                 die("unable to fork");
1511         if (!pid) {
1512                 execvp(pgm, (char *const*) arg);
1513                 exit(255);
1514         }
1515
1516         while (waitpid(pid, &status, 0) < 0) {
1517                 if (errno == EINTR)
1518                         continue;
1519                 return -1;
1520         }
1521
1522         /* Earlier we did not check the exit status because
1523          * diff exits non-zero if files are different, and
1524          * we are not interested in knowing that.  It was a
1525          * mistake which made it harder to quit a diff-*
1526          * session that uses the git-apply-patch-script as
1527          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1528          * should also exit non-zero only when it wants to
1529          * abort the entire diff-* session.
1530          */
1531         if (WIFEXITED(status) && !WEXITSTATUS(status))
1532                 return 0;
1533         return -1;
1534 }
1535
1536 /* An external diff command takes:
1537  *
1538  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1539  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1540  *
1541  */
1542 static void run_external_diff(const char *pgm,
1543                               const char *name,
1544                               const char *other,
1545                               struct diff_filespec *one,
1546                               struct diff_filespec *two,
1547                               const char *xfrm_msg,
1548                               int complete_rewrite)
1549 {
1550         const char *spawn_arg[10];
1551         struct diff_tempfile *temp = diff_temp;
1552         int retval;
1553         static int atexit_asked = 0;
1554         const char *othername;
1555         const char **arg = &spawn_arg[0];
1556
1557         othername = (other? other : name);
1558         if (one && two) {
1559                 prepare_temp_file(name, &temp[0], one);
1560                 prepare_temp_file(othername, &temp[1], two);
1561                 if (! atexit_asked &&
1562                     (temp[0].name == temp[0].tmp_path ||
1563                      temp[1].name == temp[1].tmp_path)) {
1564                         atexit_asked = 1;
1565                         atexit(remove_tempfile);
1566                 }
1567                 signal(SIGINT, remove_tempfile_on_signal);
1568         }
1569
1570         if (one && two) {
1571                 *arg++ = pgm;
1572                 *arg++ = name;
1573                 *arg++ = temp[0].name;
1574                 *arg++ = temp[0].hex;
1575                 *arg++ = temp[0].mode;
1576                 *arg++ = temp[1].name;
1577                 *arg++ = temp[1].hex;
1578                 *arg++ = temp[1].mode;
1579                 if (other) {
1580                         *arg++ = other;
1581                         *arg++ = xfrm_msg;
1582                 }
1583         } else {
1584                 *arg++ = pgm;
1585                 *arg++ = name;
1586         }
1587         *arg = NULL;
1588         retval = spawn_prog(pgm, spawn_arg);
1589         remove_tempfile();
1590         if (retval) {
1591                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1592                 exit(1);
1593         }
1594 }
1595
1596 static void run_diff_cmd(const char *pgm,
1597                          const char *name,
1598                          const char *other,
1599                          struct diff_filespec *one,
1600                          struct diff_filespec *two,
1601                          const char *xfrm_msg,
1602                          struct diff_options *o,
1603                          int complete_rewrite)
1604 {
1605         if (pgm) {
1606                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1607                                   complete_rewrite);
1608                 return;
1609         }
1610         if (one && two)
1611                 builtin_diff(name, other ? other : name,
1612                              one, two, xfrm_msg, o, complete_rewrite);
1613         else
1614                 printf("* Unmerged path %s\n", name);
1615 }
1616
1617 static void diff_fill_sha1_info(struct diff_filespec *one)
1618 {
1619         if (DIFF_FILE_VALID(one)) {
1620                 if (!one->sha1_valid) {
1621                         struct stat st;
1622                         if (lstat(one->path, &st) < 0)
1623                                 die("stat %s", one->path);
1624                         if (index_path(one->sha1, one->path, &st, 0))
1625                                 die("cannot hash %s\n", one->path);
1626                 }
1627         }
1628         else
1629                 hashclr(one->sha1);
1630 }
1631
1632 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1633 {
1634         const char *pgm = external_diff();
1635         char msg[PATH_MAX*2+300], *xfrm_msg;
1636         struct diff_filespec *one;
1637         struct diff_filespec *two;
1638         const char *name;
1639         const char *other;
1640         char *name_munged, *other_munged;
1641         int complete_rewrite = 0;
1642         int len;
1643
1644         if (DIFF_PAIR_UNMERGED(p)) {
1645                 /* unmerged */
1646                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1647                 return;
1648         }
1649
1650         name = p->one->path;
1651         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1652         name_munged = quote_one(name);
1653         other_munged = quote_one(other);
1654         one = p->one; two = p->two;
1655
1656         diff_fill_sha1_info(one);
1657         diff_fill_sha1_info(two);
1658
1659         len = 0;
1660         switch (p->status) {
1661         case DIFF_STATUS_COPIED:
1662                 len += snprintf(msg + len, sizeof(msg) - len,
1663                                 "similarity index %d%%\n"
1664                                 "copy from %s\n"
1665                                 "copy to %s\n",
1666                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1667                                 name_munged, other_munged);
1668                 break;
1669         case DIFF_STATUS_RENAMED:
1670                 len += snprintf(msg + len, sizeof(msg) - len,
1671                                 "similarity index %d%%\n"
1672                                 "rename from %s\n"
1673                                 "rename to %s\n",
1674                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1675                                 name_munged, other_munged);
1676                 break;
1677         case DIFF_STATUS_MODIFIED:
1678                 if (p->score) {
1679                         len += snprintf(msg + len, sizeof(msg) - len,
1680                                         "dissimilarity index %d%%\n",
1681                                         (int)(0.5 + p->score *
1682                                               100.0/MAX_SCORE));
1683                         complete_rewrite = 1;
1684                         break;
1685                 }
1686                 /* fallthru */
1687         default:
1688                 /* nothing */
1689                 ;
1690         }
1691
1692         if (hashcmp(one->sha1, two->sha1)) {
1693                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1694
1695                 if (o->binary) {
1696                         mmfile_t mf;
1697                         if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
1698                             (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
1699                                 abbrev = 40;
1700                 }
1701                 len += snprintf(msg + len, sizeof(msg) - len,
1702                                 "index %.*s..%.*s",
1703                                 abbrev, sha1_to_hex(one->sha1),
1704                                 abbrev, sha1_to_hex(two->sha1));
1705                 if (one->mode == two->mode)
1706                         len += snprintf(msg + len, sizeof(msg) - len,
1707                                         " %06o", one->mode);
1708                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1709         }
1710
1711         if (len)
1712                 msg[--len] = 0;
1713         xfrm_msg = len ? msg : NULL;
1714
1715         if (!pgm &&
1716             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1717             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1718                 /* a filepair that changes between file and symlink
1719                  * needs to be split into deletion and creation.
1720                  */
1721                 struct diff_filespec *null = alloc_filespec(two->path);
1722                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1723                 free(null);
1724                 null = alloc_filespec(one->path);
1725                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1726                 free(null);
1727         }
1728         else
1729                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1730                              complete_rewrite);
1731
1732         free(name_munged);
1733         free(other_munged);
1734 }
1735
1736 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1737                          struct diffstat_t *diffstat)
1738 {
1739         const char *name;
1740         const char *other;
1741         int complete_rewrite = 0;
1742
1743         if (DIFF_PAIR_UNMERGED(p)) {
1744                 /* unmerged */
1745                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1746                 return;
1747         }
1748
1749         name = p->one->path;
1750         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1751
1752         diff_fill_sha1_info(p->one);
1753         diff_fill_sha1_info(p->two);
1754
1755         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1756                 complete_rewrite = 1;
1757         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1758 }
1759
1760 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1761 {
1762         const char *name;
1763         const char *other;
1764
1765         if (DIFF_PAIR_UNMERGED(p)) {
1766                 /* unmerged */
1767                 return;
1768         }
1769
1770         name = p->one->path;
1771         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1772
1773         diff_fill_sha1_info(p->one);
1774         diff_fill_sha1_info(p->two);
1775
1776         builtin_checkdiff(name, other, p->one, p->two);
1777 }
1778
1779 void diff_setup(struct diff_options *options)
1780 {
1781         memset(options, 0, sizeof(*options));
1782         options->line_termination = '\n';
1783         options->break_opt = -1;
1784         options->rename_limit = -1;
1785         options->context = 3;
1786         options->msg_sep = "";
1787
1788         options->change = diff_change;
1789         options->add_remove = diff_addremove;
1790         options->color_diff = diff_use_color_default;
1791         options->detect_rename = diff_detect_rename_default;
1792 }
1793
1794 int diff_setup_done(struct diff_options *options)
1795 {
1796         int count = 0;
1797
1798         if (options->output_format & DIFF_FORMAT_NAME)
1799                 count++;
1800         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
1801                 count++;
1802         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
1803                 count++;
1804         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
1805                 count++;
1806         if (count > 1)
1807                 die("--name-only, --name-status, --check and -s are mutually exclusive");
1808
1809         if (options->find_copies_harder)
1810                 options->detect_rename = DIFF_DETECT_COPY;
1811
1812         if (options->output_format & (DIFF_FORMAT_NAME |
1813                                       DIFF_FORMAT_NAME_STATUS |
1814                                       DIFF_FORMAT_CHECKDIFF |
1815                                       DIFF_FORMAT_NO_OUTPUT))
1816                 options->output_format &= ~(DIFF_FORMAT_RAW |
1817                                             DIFF_FORMAT_NUMSTAT |
1818                                             DIFF_FORMAT_DIFFSTAT |
1819                                             DIFF_FORMAT_SHORTSTAT |
1820                                             DIFF_FORMAT_SUMMARY |
1821                                             DIFF_FORMAT_PATCH);
1822
1823         /*
1824          * These cases always need recursive; we do not drop caller-supplied
1825          * recursive bits for other formats here.
1826          */
1827         if (options->output_format & (DIFF_FORMAT_PATCH |
1828                                       DIFF_FORMAT_NUMSTAT |
1829                                       DIFF_FORMAT_DIFFSTAT |
1830                                       DIFF_FORMAT_SHORTSTAT |
1831                                       DIFF_FORMAT_SUMMARY |
1832                                       DIFF_FORMAT_CHECKDIFF))
1833                 options->recursive = 1;
1834         /*
1835          * Also pickaxe would not work very well if you do not say recursive
1836          */
1837         if (options->pickaxe)
1838                 options->recursive = 1;
1839
1840         if (options->detect_rename && options->rename_limit < 0)
1841                 options->rename_limit = diff_rename_limit_default;
1842         if (options->setup & DIFF_SETUP_USE_CACHE) {
1843                 if (!active_cache)
1844                         /* read-cache does not die even when it fails
1845                          * so it is safe for us to do this here.  Also
1846                          * it does not smudge active_cache or active_nr
1847                          * when it fails, so we do not have to worry about
1848                          * cleaning it up ourselves either.
1849                          */
1850                         read_cache();
1851         }
1852         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1853                 use_size_cache = 1;
1854         if (options->abbrev <= 0 || 40 < options->abbrev)
1855                 options->abbrev = 40; /* full */
1856
1857         return 0;
1858 }
1859
1860 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1861 {
1862         char c, *eq;
1863         int len;
1864
1865         if (*arg != '-')
1866                 return 0;
1867         c = *++arg;
1868         if (!c)
1869                 return 0;
1870         if (c == arg_short) {
1871                 c = *++arg;
1872                 if (!c)
1873                         return 1;
1874                 if (val && isdigit(c)) {
1875                         char *end;
1876                         int n = strtoul(arg, &end, 10);
1877                         if (*end)
1878                                 return 0;
1879                         *val = n;
1880                         return 1;
1881                 }
1882                 return 0;
1883         }
1884         if (c != '-')
1885                 return 0;
1886         arg++;
1887         eq = strchr(arg, '=');
1888         if (eq)
1889                 len = eq - arg;
1890         else
1891                 len = strlen(arg);
1892         if (!len || strncmp(arg, arg_long, len))
1893                 return 0;
1894         if (eq) {
1895                 int n;
1896                 char *end;
1897                 if (!isdigit(*++eq))
1898                         return 0;
1899                 n = strtoul(eq, &end, 10);
1900                 if (*end)
1901                         return 0;
1902                 *val = n;
1903         }
1904         return 1;
1905 }
1906
1907 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1908 {
1909         const char *arg = av[0];
1910         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1911                 options->output_format |= DIFF_FORMAT_PATCH;
1912         else if (opt_arg(arg, 'U', "unified", &options->context))
1913                 options->output_format |= DIFF_FORMAT_PATCH;
1914         else if (!strcmp(arg, "--raw"))
1915                 options->output_format |= DIFF_FORMAT_RAW;
1916         else if (!strcmp(arg, "--patch-with-raw")) {
1917                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
1918         }
1919         else if (!strcmp(arg, "--numstat")) {
1920                 options->output_format |= DIFF_FORMAT_NUMSTAT;
1921         }
1922         else if (!strcmp(arg, "--shortstat")) {
1923                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
1924         }
1925         else if (!strncmp(arg, "--stat", 6)) {
1926                 char *end;
1927                 int width = options->stat_width;
1928                 int name_width = options->stat_name_width;
1929                 arg += 6;
1930                 end = (char *)arg;
1931
1932                 switch (*arg) {
1933                 case '-':
1934                         if (!strncmp(arg, "-width=", 7))
1935                                 width = strtoul(arg + 7, &end, 10);
1936                         else if (!strncmp(arg, "-name-width=", 12))
1937                                 name_width = strtoul(arg + 12, &end, 10);
1938                         break;
1939                 case '=':
1940                         width = strtoul(arg+1, &end, 10);
1941                         if (*end == ',')
1942                                 name_width = strtoul(end+1, &end, 10);
1943                 }
1944
1945                 /* Important! This checks all the error cases! */
1946                 if (*end)
1947                         return 0;
1948                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
1949                 options->stat_name_width = name_width;
1950                 options->stat_width = width;
1951         }
1952         else if (!strcmp(arg, "--check"))
1953                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
1954         else if (!strcmp(arg, "--summary"))
1955                 options->output_format |= DIFF_FORMAT_SUMMARY;
1956         else if (!strcmp(arg, "--patch-with-stat")) {
1957                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
1958         }
1959         else if (!strcmp(arg, "-z"))
1960                 options->line_termination = 0;
1961         else if (!strncmp(arg, "-l", 2))
1962                 options->rename_limit = strtoul(arg+2, NULL, 10);
1963         else if (!strcmp(arg, "--full-index"))
1964                 options->full_index = 1;
1965         else if (!strcmp(arg, "--binary")) {
1966                 options->output_format |= DIFF_FORMAT_PATCH;
1967                 options->binary = 1;
1968         }
1969         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
1970                 options->text = 1;
1971         }
1972         else if (!strcmp(arg, "--name-only"))
1973                 options->output_format |= DIFF_FORMAT_NAME;
1974         else if (!strcmp(arg, "--name-status"))
1975                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
1976         else if (!strcmp(arg, "-R"))
1977                 options->reverse_diff = 1;
1978         else if (!strncmp(arg, "-S", 2))
1979                 options->pickaxe = arg + 2;
1980         else if (!strcmp(arg, "-s")) {
1981                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
1982         }
1983         else if (!strncmp(arg, "-O", 2))
1984                 options->orderfile = arg + 2;
1985         else if (!strncmp(arg, "--diff-filter=", 14))
1986                 options->filter = arg + 14;
1987         else if (!strcmp(arg, "--pickaxe-all"))
1988                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1989         else if (!strcmp(arg, "--pickaxe-regex"))
1990                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1991         else if (!strncmp(arg, "-B", 2)) {
1992                 if ((options->break_opt =
1993                      diff_scoreopt_parse(arg)) == -1)
1994                         return -1;
1995         }
1996         else if (!strncmp(arg, "-M", 2)) {
1997                 if ((options->rename_score =
1998                      diff_scoreopt_parse(arg)) == -1)
1999                         return -1;
2000                 options->detect_rename = DIFF_DETECT_RENAME;
2001         }
2002         else if (!strncmp(arg, "-C", 2)) {
2003                 if ((options->rename_score =
2004                      diff_scoreopt_parse(arg)) == -1)
2005                         return -1;
2006                 options->detect_rename = DIFF_DETECT_COPY;
2007         }
2008         else if (!strcmp(arg, "--find-copies-harder"))
2009                 options->find_copies_harder = 1;
2010         else if (!strcmp(arg, "--abbrev"))
2011                 options->abbrev = DEFAULT_ABBREV;
2012         else if (!strncmp(arg, "--abbrev=", 9)) {
2013                 options->abbrev = strtoul(arg + 9, NULL, 10);
2014                 if (options->abbrev < MINIMUM_ABBREV)
2015                         options->abbrev = MINIMUM_ABBREV;
2016                 else if (40 < options->abbrev)
2017                         options->abbrev = 40;
2018         }
2019         else if (!strcmp(arg, "--color"))
2020                 options->color_diff = 1;
2021         else if (!strcmp(arg, "--no-color"))
2022                 options->color_diff = 0;
2023         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2024                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2025         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2026                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2027         else if (!strcmp(arg, "--color-words"))
2028                 options->color_diff = options->color_diff_words = 1;
2029         else if (!strcmp(arg, "--no-renames"))
2030                 options->detect_rename = 0;
2031         else
2032                 return 0;
2033         return 1;
2034 }
2035
2036 static int parse_num(const char **cp_p)
2037 {
2038         unsigned long num, scale;
2039         int ch, dot;
2040         const char *cp = *cp_p;
2041
2042         num = 0;
2043         scale = 1;
2044         dot = 0;
2045         for(;;) {
2046                 ch = *cp;
2047                 if ( !dot && ch == '.' ) {
2048                         scale = 1;
2049                         dot = 1;
2050                 } else if ( ch == '%' ) {
2051                         scale = dot ? scale*100 : 100;
2052                         cp++;   /* % is always at the end */
2053                         break;
2054                 } else if ( ch >= '0' && ch <= '9' ) {
2055                         if ( scale < 100000 ) {
2056                                 scale *= 10;
2057                                 num = (num*10) + (ch-'0');
2058                         }
2059                 } else {
2060                         break;
2061                 }
2062                 cp++;
2063         }
2064         *cp_p = cp;
2065
2066         /* user says num divided by scale and we say internally that
2067          * is MAX_SCORE * num / scale.
2068          */
2069         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
2070 }
2071
2072 int diff_scoreopt_parse(const char *opt)
2073 {
2074         int opt1, opt2, cmd;
2075
2076         if (*opt++ != '-')
2077                 return -1;
2078         cmd = *opt++;
2079         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2080                 return -1; /* that is not a -M, -C nor -B option */
2081
2082         opt1 = parse_num(&opt);
2083         if (cmd != 'B')
2084                 opt2 = 0;
2085         else {
2086                 if (*opt == 0)
2087                         opt2 = 0;
2088                 else if (*opt != '/')
2089                         return -1; /* we expect -B80/99 or -B80 */
2090                 else {
2091                         opt++;
2092                         opt2 = parse_num(&opt);
2093                 }
2094         }
2095         if (*opt != 0)
2096                 return -1;
2097         return opt1 | (opt2 << 16);
2098 }
2099
2100 struct diff_queue_struct diff_queued_diff;
2101
2102 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2103 {
2104         if (queue->alloc <= queue->nr) {
2105                 queue->alloc = alloc_nr(queue->alloc);
2106                 queue->queue = xrealloc(queue->queue,
2107                                         sizeof(dp) * queue->alloc);
2108         }
2109         queue->queue[queue->nr++] = dp;
2110 }
2111
2112 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2113                                  struct diff_filespec *one,
2114                                  struct diff_filespec *two)
2115 {
2116         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2117         dp->one = one;
2118         dp->two = two;
2119         if (queue)
2120                 diff_q(queue, dp);
2121         return dp;
2122 }
2123
2124 void diff_free_filepair(struct diff_filepair *p)
2125 {
2126         diff_free_filespec_data(p->one);
2127         diff_free_filespec_data(p->two);
2128         free(p->one);
2129         free(p->two);
2130         free(p);
2131 }
2132
2133 /* This is different from find_unique_abbrev() in that
2134  * it stuffs the result with dots for alignment.
2135  */
2136 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2137 {
2138         int abblen;
2139         const char *abbrev;
2140         if (len == 40)
2141                 return sha1_to_hex(sha1);
2142
2143         abbrev = find_unique_abbrev(sha1, len);
2144         if (!abbrev)
2145                 return sha1_to_hex(sha1);
2146         abblen = strlen(abbrev);
2147         if (abblen < 37) {
2148                 static char hex[41];
2149                 if (len < abblen && abblen <= len + 2)
2150                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2151                 else
2152                         sprintf(hex, "%s...", abbrev);
2153                 return hex;
2154         }
2155         return sha1_to_hex(sha1);
2156 }
2157
2158 static void diff_flush_raw(struct diff_filepair *p,
2159                            struct diff_options *options)
2160 {
2161         int two_paths;
2162         char status[10];
2163         int abbrev = options->abbrev;
2164         const char *path_one, *path_two;
2165         int inter_name_termination = '\t';
2166         int line_termination = options->line_termination;
2167
2168         if (!line_termination)
2169                 inter_name_termination = 0;
2170
2171         path_one = p->one->path;
2172         path_two = p->two->path;
2173         if (line_termination) {
2174                 path_one = quote_one(path_one);
2175                 path_two = quote_one(path_two);
2176         }
2177
2178         if (p->score)
2179                 sprintf(status, "%c%03d", p->status,
2180                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
2181         else {
2182                 status[0] = p->status;
2183                 status[1] = 0;
2184         }
2185         switch (p->status) {
2186         case DIFF_STATUS_COPIED:
2187         case DIFF_STATUS_RENAMED:
2188                 two_paths = 1;
2189                 break;
2190         case DIFF_STATUS_ADDED:
2191         case DIFF_STATUS_DELETED:
2192                 two_paths = 0;
2193                 break;
2194         default:
2195                 two_paths = 0;
2196                 break;
2197         }
2198         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2199                 printf(":%06o %06o %s ",
2200                        p->one->mode, p->two->mode,
2201                        diff_unique_abbrev(p->one->sha1, abbrev));
2202                 printf("%s ",
2203                        diff_unique_abbrev(p->two->sha1, abbrev));
2204         }
2205         printf("%s%c%s", status, inter_name_termination, path_one);
2206         if (two_paths)
2207                 printf("%c%s", inter_name_termination, path_two);
2208         putchar(line_termination);
2209         if (path_one != p->one->path)
2210                 free((void*)path_one);
2211         if (path_two != p->two->path)
2212                 free((void*)path_two);
2213 }
2214
2215 static void diff_flush_name(struct diff_filepair *p, struct diff_options *opt)
2216 {
2217         char *path = p->two->path;
2218
2219         if (opt->line_termination)
2220                 path = quote_one(p->two->path);
2221         printf("%s%c", path, opt->line_termination);
2222         if (p->two->path != path)
2223                 free(path);
2224 }
2225
2226 int diff_unmodified_pair(struct diff_filepair *p)
2227 {
2228         /* This function is written stricter than necessary to support
2229          * the currently implemented transformers, but the idea is to
2230          * let transformers to produce diff_filepairs any way they want,
2231          * and filter and clean them up here before producing the output.
2232          */
2233         struct diff_filespec *one, *two;
2234
2235         if (DIFF_PAIR_UNMERGED(p))
2236                 return 0; /* unmerged is interesting */
2237
2238         one = p->one;
2239         two = p->two;
2240
2241         /* deletion, addition, mode or type change
2242          * and rename are all interesting.
2243          */
2244         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2245             DIFF_PAIR_MODE_CHANGED(p) ||
2246             strcmp(one->path, two->path))
2247                 return 0;
2248
2249         /* both are valid and point at the same path.  that is, we are
2250          * dealing with a change.
2251          */
2252         if (one->sha1_valid && two->sha1_valid &&
2253             !hashcmp(one->sha1, two->sha1))
2254                 return 1; /* no change */
2255         if (!one->sha1_valid && !two->sha1_valid)
2256                 return 1; /* both look at the same file on the filesystem. */
2257         return 0;
2258 }
2259
2260 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2261 {
2262         if (diff_unmodified_pair(p))
2263                 return;
2264
2265         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2266             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2267                 return; /* no tree diffs in patch format */
2268
2269         run_diff(p, o);
2270 }
2271
2272 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2273                             struct diffstat_t *diffstat)
2274 {
2275         if (diff_unmodified_pair(p))
2276                 return;
2277
2278         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2279             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2280                 return; /* no tree diffs in patch format */
2281
2282         run_diffstat(p, o, diffstat);
2283 }
2284
2285 static void diff_flush_checkdiff(struct diff_filepair *p,
2286                 struct diff_options *o)
2287 {
2288         if (diff_unmodified_pair(p))
2289                 return;
2290
2291         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2292             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2293                 return; /* no tree diffs in patch format */
2294
2295         run_checkdiff(p, o);
2296 }
2297
2298 int diff_queue_is_empty(void)
2299 {
2300         struct diff_queue_struct *q = &diff_queued_diff;
2301         int i;
2302         for (i = 0; i < q->nr; i++)
2303                 if (!diff_unmodified_pair(q->queue[i]))
2304                         return 0;
2305         return 1;
2306 }
2307
2308 #if DIFF_DEBUG
2309 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2310 {
2311         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2312                 x, one ? one : "",
2313                 s->path,
2314                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2315                 s->mode,
2316                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2317         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2318                 x, one ? one : "",
2319                 s->size, s->xfrm_flags);
2320 }
2321
2322 void diff_debug_filepair(const struct diff_filepair *p, int i)
2323 {
2324         diff_debug_filespec(p->one, i, "one");
2325         diff_debug_filespec(p->two, i, "two");
2326         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2327                 p->score, p->status ? p->status : '?',
2328                 p->source_stays, p->broken_pair);
2329 }
2330
2331 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2332 {
2333         int i;
2334         if (msg)
2335                 fprintf(stderr, "%s\n", msg);
2336         fprintf(stderr, "q->nr = %d\n", q->nr);
2337         for (i = 0; i < q->nr; i++) {
2338                 struct diff_filepair *p = q->queue[i];
2339                 diff_debug_filepair(p, i);
2340         }
2341 }
2342 #endif
2343
2344 static void diff_resolve_rename_copy(void)
2345 {
2346         int i, j;
2347         struct diff_filepair *p, *pp;
2348         struct diff_queue_struct *q = &diff_queued_diff;
2349
2350         diff_debug_queue("resolve-rename-copy", q);
2351
2352         for (i = 0; i < q->nr; i++) {
2353                 p = q->queue[i];
2354                 p->status = 0; /* undecided */
2355                 if (DIFF_PAIR_UNMERGED(p))
2356                         p->status = DIFF_STATUS_UNMERGED;
2357                 else if (!DIFF_FILE_VALID(p->one))
2358                         p->status = DIFF_STATUS_ADDED;
2359                 else if (!DIFF_FILE_VALID(p->two))
2360                         p->status = DIFF_STATUS_DELETED;
2361                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2362                         p->status = DIFF_STATUS_TYPE_CHANGED;
2363
2364                 /* from this point on, we are dealing with a pair
2365                  * whose both sides are valid and of the same type, i.e.
2366                  * either in-place edit or rename/copy edit.
2367                  */
2368                 else if (DIFF_PAIR_RENAME(p)) {
2369                         if (p->source_stays) {
2370                                 p->status = DIFF_STATUS_COPIED;
2371                                 continue;
2372                         }
2373                         /* See if there is some other filepair that
2374                          * copies from the same source as us.  If so
2375                          * we are a copy.  Otherwise we are either a
2376                          * copy if the path stays, or a rename if it
2377                          * does not, but we already handled "stays" case.
2378                          */
2379                         for (j = i + 1; j < q->nr; j++) {
2380                                 pp = q->queue[j];
2381                                 if (strcmp(pp->one->path, p->one->path))
2382                                         continue; /* not us */
2383                                 if (!DIFF_PAIR_RENAME(pp))
2384                                         continue; /* not a rename/copy */
2385                                 /* pp is a rename/copy from the same source */
2386                                 p->status = DIFF_STATUS_COPIED;
2387                                 break;
2388                         }
2389                         if (!p->status)
2390                                 p->status = DIFF_STATUS_RENAMED;
2391                 }
2392                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2393                          p->one->mode != p->two->mode)
2394                         p->status = DIFF_STATUS_MODIFIED;
2395                 else {
2396                         /* This is a "no-change" entry and should not
2397                          * happen anymore, but prepare for broken callers.
2398                          */
2399                         error("feeding unmodified %s to diffcore",
2400                               p->one->path);
2401                         p->status = DIFF_STATUS_UNKNOWN;
2402                 }
2403         }
2404         diff_debug_queue("resolve-rename-copy done", q);
2405 }
2406
2407 static int check_pair_status(struct diff_filepair *p)
2408 {
2409         switch (p->status) {
2410         case DIFF_STATUS_UNKNOWN:
2411                 return 0;
2412         case 0:
2413                 die("internal error in diff-resolve-rename-copy");
2414         default:
2415                 return 1;
2416         }
2417 }
2418
2419 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2420 {
2421         int fmt = opt->output_format;
2422
2423         if (fmt & DIFF_FORMAT_CHECKDIFF)
2424                 diff_flush_checkdiff(p, opt);
2425         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2426                 diff_flush_raw(p, opt);
2427         else if (fmt & DIFF_FORMAT_NAME)
2428                 diff_flush_name(p, opt);
2429 }
2430
2431 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2432 {
2433         char *name = quote_one(fs->path);
2434         if (fs->mode)
2435                 printf(" %s mode %06o %s\n", newdelete, fs->mode, name);
2436         else
2437                 printf(" %s %s\n", newdelete, name);
2438         free(name);
2439 }
2440
2441
2442 static void show_mode_change(struct diff_filepair *p, int show_name)
2443 {
2444         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2445                 if (show_name) {
2446                         char *name = quote_one(p->two->path);
2447                         printf(" mode change %06o => %06o %s\n",
2448                                p->one->mode, p->two->mode, name);
2449                         free(name);
2450                 }
2451                 else
2452                         printf(" mode change %06o => %06o\n",
2453                                p->one->mode, p->two->mode);
2454         }
2455 }
2456
2457 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2458 {
2459         char *names = pprint_rename(p->one->path, p->two->path);
2460
2461         printf(" %s %s (%d%%)\n", renamecopy, names,
2462                (int)(0.5 + p->score * 100.0/MAX_SCORE));
2463         free(names);
2464         show_mode_change(p, 0);
2465 }
2466
2467 static void diff_summary(struct diff_filepair *p)
2468 {
2469         switch(p->status) {
2470         case DIFF_STATUS_DELETED:
2471                 show_file_mode_name("delete", p->one);
2472                 break;
2473         case DIFF_STATUS_ADDED:
2474                 show_file_mode_name("create", p->two);
2475                 break;
2476         case DIFF_STATUS_COPIED:
2477                 show_rename_copy("copy", p);
2478                 break;
2479         case DIFF_STATUS_RENAMED:
2480                 show_rename_copy("rename", p);
2481                 break;
2482         default:
2483                 if (p->score) {
2484                         char *name = quote_one(p->two->path);
2485                         printf(" rewrite %s (%d%%)\n", name,
2486                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2487                         free(name);
2488                         show_mode_change(p, 0);
2489                 } else  show_mode_change(p, 1);
2490                 break;
2491         }
2492 }
2493
2494 struct patch_id_t {
2495         struct xdiff_emit_state xm;
2496         SHA_CTX *ctx;
2497         int patchlen;
2498 };
2499
2500 static int remove_space(char *line, int len)
2501 {
2502         int i;
2503         char *dst = line;
2504         unsigned char c;
2505
2506         for (i = 0; i < len; i++)
2507                 if (!isspace((c = line[i])))
2508                         *dst++ = c;
2509
2510         return dst - line;
2511 }
2512
2513 static void patch_id_consume(void *priv, char *line, unsigned long len)
2514 {
2515         struct patch_id_t *data = priv;
2516         int new_len;
2517
2518         /* Ignore line numbers when computing the SHA1 of the patch */
2519         if (!strncmp(line, "@@ -", 4))
2520                 return;
2521
2522         new_len = remove_space(line, len);
2523
2524         SHA1_Update(data->ctx, line, new_len);
2525         data->patchlen += new_len;
2526 }
2527
2528 /* returns 0 upon success, and writes result into sha1 */
2529 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2530 {
2531         struct diff_queue_struct *q = &diff_queued_diff;
2532         int i;
2533         SHA_CTX ctx;
2534         struct patch_id_t data;
2535         char buffer[PATH_MAX * 4 + 20];
2536
2537         SHA1_Init(&ctx);
2538         memset(&data, 0, sizeof(struct patch_id_t));
2539         data.ctx = &ctx;
2540         data.xm.consume = patch_id_consume;
2541
2542         for (i = 0; i < q->nr; i++) {
2543                 xpparam_t xpp;
2544                 xdemitconf_t xecfg;
2545                 xdemitcb_t ecb;
2546                 mmfile_t mf1, mf2;
2547                 struct diff_filepair *p = q->queue[i];
2548                 int len1, len2;
2549
2550                 if (p->status == 0)
2551                         return error("internal diff status error");
2552                 if (p->status == DIFF_STATUS_UNKNOWN)
2553                         continue;
2554                 if (diff_unmodified_pair(p))
2555                         continue;
2556                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2557                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2558                         continue;
2559                 if (DIFF_PAIR_UNMERGED(p))
2560                         continue;
2561
2562                 diff_fill_sha1_info(p->one);
2563                 diff_fill_sha1_info(p->two);
2564                 if (fill_mmfile(&mf1, p->one) < 0 ||
2565                                 fill_mmfile(&mf2, p->two) < 0)
2566                         return error("unable to read files to diff");
2567
2568                 /* Maybe hash p->two? into the patch id? */
2569                 if (mmfile_is_binary(&mf2))
2570                         continue;
2571
2572                 len1 = remove_space(p->one->path, strlen(p->one->path));
2573                 len2 = remove_space(p->two->path, strlen(p->two->path));
2574                 if (p->one->mode == 0)
2575                         len1 = snprintf(buffer, sizeof(buffer),
2576                                         "diff--gita/%.*sb/%.*s"
2577                                         "newfilemode%06o"
2578                                         "---/dev/null"
2579                                         "+++b/%.*s",
2580                                         len1, p->one->path,
2581                                         len2, p->two->path,
2582                                         p->two->mode,
2583                                         len2, p->two->path);
2584                 else if (p->two->mode == 0)
2585                         len1 = snprintf(buffer, sizeof(buffer),
2586                                         "diff--gita/%.*sb/%.*s"
2587                                         "deletedfilemode%06o"
2588                                         "---a/%.*s"
2589                                         "+++/dev/null",
2590                                         len1, p->one->path,
2591                                         len2, p->two->path,
2592                                         p->one->mode,
2593                                         len1, p->one->path);
2594                 else
2595                         len1 = snprintf(buffer, sizeof(buffer),
2596                                         "diff--gita/%.*sb/%.*s"
2597                                         "---a/%.*s"
2598                                         "+++b/%.*s",
2599                                         len1, p->one->path,
2600                                         len2, p->two->path,
2601                                         len1, p->one->path,
2602                                         len2, p->two->path);
2603                 SHA1_Update(&ctx, buffer, len1);
2604
2605                 xpp.flags = XDF_NEED_MINIMAL;
2606                 xecfg.ctxlen = 3;
2607                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2608                 ecb.outf = xdiff_outf;
2609                 ecb.priv = &data;
2610                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2611         }
2612
2613         SHA1_Final(sha1, &ctx);
2614         return 0;
2615 }
2616
2617 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2618 {
2619         struct diff_queue_struct *q = &diff_queued_diff;
2620         int i;
2621         int result = diff_get_patch_id(options, sha1);
2622
2623         for (i = 0; i < q->nr; i++)
2624                 diff_free_filepair(q->queue[i]);
2625
2626         free(q->queue);
2627         q->queue = NULL;
2628         q->nr = q->alloc = 0;
2629
2630         return result;
2631 }
2632
2633 static int is_summary_empty(const struct diff_queue_struct *q)
2634 {
2635         int i;
2636
2637         for (i = 0; i < q->nr; i++) {
2638                 const struct diff_filepair *p = q->queue[i];
2639
2640                 switch (p->status) {
2641                 case DIFF_STATUS_DELETED:
2642                 case DIFF_STATUS_ADDED:
2643                 case DIFF_STATUS_COPIED:
2644                 case DIFF_STATUS_RENAMED:
2645                         return 0;
2646                 default:
2647                         if (p->score)
2648                                 return 0;
2649                         if (p->one->mode && p->two->mode &&
2650                             p->one->mode != p->two->mode)
2651                                 return 0;
2652                         break;
2653                 }
2654         }
2655         return 1;
2656 }
2657
2658 void diff_flush(struct diff_options *options)
2659 {
2660         struct diff_queue_struct *q = &diff_queued_diff;
2661         int i, output_format = options->output_format;
2662         int separator = 0;
2663
2664         /*
2665          * Order: raw, stat, summary, patch
2666          * or:    name/name-status/checkdiff (other bits clear)
2667          */
2668         if (!q->nr)
2669                 goto free_queue;
2670
2671         if (output_format & (DIFF_FORMAT_RAW |
2672                              DIFF_FORMAT_NAME |
2673                              DIFF_FORMAT_NAME_STATUS |
2674                              DIFF_FORMAT_CHECKDIFF)) {
2675                 for (i = 0; i < q->nr; i++) {
2676                         struct diff_filepair *p = q->queue[i];
2677                         if (check_pair_status(p))
2678                                 flush_one_pair(p, options);
2679                 }
2680                 separator++;
2681         }
2682
2683         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2684                 struct diffstat_t diffstat;
2685
2686                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2687                 diffstat.xm.consume = diffstat_consume;
2688                 for (i = 0; i < q->nr; i++) {
2689                         struct diff_filepair *p = q->queue[i];
2690                         if (check_pair_status(p))
2691                                 diff_flush_stat(p, options, &diffstat);
2692                 }
2693                 if (output_format & DIFF_FORMAT_NUMSTAT)
2694                         show_numstat(&diffstat, options);
2695                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2696                         show_stats(&diffstat, options);
2697                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2698                         show_shortstats(&diffstat);
2699                 separator++;
2700         }
2701
2702         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2703                 for (i = 0; i < q->nr; i++)
2704                         diff_summary(q->queue[i]);
2705                 separator++;
2706         }
2707
2708         if (output_format & DIFF_FORMAT_PATCH) {
2709                 if (separator) {
2710                         if (options->stat_sep) {
2711                                 /* attach patch instead of inline */
2712                                 fputs(options->stat_sep, stdout);
2713                         } else {
2714                                 putchar(options->line_termination);
2715                         }
2716                 }
2717
2718                 for (i = 0; i < q->nr; i++) {
2719                         struct diff_filepair *p = q->queue[i];
2720                         if (check_pair_status(p))
2721                                 diff_flush_patch(p, options);
2722                 }
2723         }
2724
2725         if (output_format & DIFF_FORMAT_CALLBACK)
2726                 options->format_callback(q, options, options->format_callback_data);
2727
2728         for (i = 0; i < q->nr; i++)
2729                 diff_free_filepair(q->queue[i]);
2730 free_queue:
2731         free(q->queue);
2732         q->queue = NULL;
2733         q->nr = q->alloc = 0;
2734 }
2735
2736 static void diffcore_apply_filter(const char *filter)
2737 {
2738         int i;
2739         struct diff_queue_struct *q = &diff_queued_diff;
2740         struct diff_queue_struct outq;
2741         outq.queue = NULL;
2742         outq.nr = outq.alloc = 0;
2743
2744         if (!filter)
2745                 return;
2746
2747         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2748                 int found;
2749                 for (i = found = 0; !found && i < q->nr; i++) {
2750                         struct diff_filepair *p = q->queue[i];
2751                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2752                              ((p->score &&
2753                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2754                               (!p->score &&
2755                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2756                             ((p->status != DIFF_STATUS_MODIFIED) &&
2757                              strchr(filter, p->status)))
2758                                 found++;
2759                 }
2760                 if (found)
2761                         return;
2762
2763                 /* otherwise we will clear the whole queue
2764                  * by copying the empty outq at the end of this
2765                  * function, but first clear the current entries
2766                  * in the queue.
2767                  */
2768                 for (i = 0; i < q->nr; i++)
2769                         diff_free_filepair(q->queue[i]);
2770         }
2771         else {
2772                 /* Only the matching ones */
2773                 for (i = 0; i < q->nr; i++) {
2774                         struct diff_filepair *p = q->queue[i];
2775
2776                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2777                              ((p->score &&
2778                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2779                               (!p->score &&
2780                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2781                             ((p->status != DIFF_STATUS_MODIFIED) &&
2782                              strchr(filter, p->status)))
2783                                 diff_q(&outq, p);
2784                         else
2785                                 diff_free_filepair(p);
2786                 }
2787         }
2788         free(q->queue);
2789         *q = outq;
2790 }
2791
2792 void diffcore_std(struct diff_options *options)
2793 {
2794         if (options->break_opt != -1)
2795                 diffcore_break(options->break_opt);
2796         if (options->detect_rename)
2797                 diffcore_rename(options);
2798         if (options->break_opt != -1)
2799                 diffcore_merge_broken();
2800         if (options->pickaxe)
2801                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2802         if (options->orderfile)
2803                 diffcore_order(options->orderfile);
2804         diff_resolve_rename_copy();
2805         diffcore_apply_filter(options->filter);
2806 }
2807
2808
2809 void diffcore_std_no_resolve(struct diff_options *options)
2810 {
2811         if (options->pickaxe)
2812                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2813         if (options->orderfile)
2814                 diffcore_order(options->orderfile);
2815         diffcore_apply_filter(options->filter);
2816 }
2817
2818 void diff_addremove(struct diff_options *options,
2819                     int addremove, unsigned mode,
2820                     const unsigned char *sha1,
2821                     const char *base, const char *path)
2822 {
2823         char concatpath[PATH_MAX];
2824         struct diff_filespec *one, *two;
2825
2826         /* This may look odd, but it is a preparation for
2827          * feeding "there are unchanged files which should
2828          * not produce diffs, but when you are doing copy
2829          * detection you would need them, so here they are"
2830          * entries to the diff-core.  They will be prefixed
2831          * with something like '=' or '*' (I haven't decided
2832          * which but should not make any difference).
2833          * Feeding the same new and old to diff_change() 
2834          * also has the same effect.
2835          * Before the final output happens, they are pruned after
2836          * merged into rename/copy pairs as appropriate.
2837          */
2838         if (options->reverse_diff)
2839                 addremove = (addremove == '+' ? '-' :
2840                              addremove == '-' ? '+' : addremove);
2841
2842         if (!path) path = "";
2843         sprintf(concatpath, "%s%s", base, path);
2844         one = alloc_filespec(concatpath);
2845         two = alloc_filespec(concatpath);
2846
2847         if (addremove != '+')
2848                 fill_filespec(one, sha1, mode);
2849         if (addremove != '-')
2850                 fill_filespec(two, sha1, mode);
2851
2852         diff_queue(&diff_queued_diff, one, two);
2853 }
2854
2855 void diff_change(struct diff_options *options,
2856                  unsigned old_mode, unsigned new_mode,
2857                  const unsigned char *old_sha1,
2858                  const unsigned char *new_sha1,
2859                  const char *base, const char *path) 
2860 {
2861         char concatpath[PATH_MAX];
2862         struct diff_filespec *one, *two;
2863
2864         if (options->reverse_diff) {
2865                 unsigned tmp;
2866                 const unsigned char *tmp_c;
2867                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2868                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2869         }
2870         if (!path) path = "";
2871         sprintf(concatpath, "%s%s", base, path);
2872         one = alloc_filespec(concatpath);
2873         two = alloc_filespec(concatpath);
2874         fill_filespec(one, old_sha1, old_mode);
2875         fill_filespec(two, new_sha1, new_mode);
2876
2877         diff_queue(&diff_queued_diff, one, two);
2878 }
2879
2880 void diff_unmerge(struct diff_options *options,
2881                   const char *path,
2882                   unsigned mode, const unsigned char *sha1)
2883 {
2884         struct diff_filespec *one, *two;
2885         one = alloc_filespec(path);
2886         two = alloc_filespec(path);
2887         fill_filespec(one, sha1, mode);
2888         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
2889 }