Merge http://www.kernel.org/pub/scm/gitk/gitk
[git] / diffcore-pickaxe.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "diff.h"
6 #include "diffcore.h"
7
8 static unsigned int contains(struct diff_filespec *one,
9                              const char *needle, unsigned long len)
10 {
11         unsigned int cnt;
12         unsigned long offset, sz;
13         const char *data;
14         if (diff_populate_filespec(one, 0))
15                 return 0;
16
17         sz = one->size;
18         data = one->data;
19         cnt = 0;
20
21         /* Yes, I've heard of strstr(), but the thing is *data may
22          * not be NUL terminated.  Sue me.
23          */
24         for (offset = 0; offset + len <= sz; offset++) {
25                 /* we count non-overlapping occurrences of needle */
26                 if (!memcmp(needle, data + offset, len)) {
27                         offset += len - 1;
28                         cnt++;
29                 }
30         }
31         return cnt;
32 }
33
34 void diffcore_pickaxe(const char *needle, int opts)
35 {
36         struct diff_queue_struct *q = &diff_queued_diff;
37         unsigned long len = strlen(needle);
38         int i, has_changes;
39         struct diff_queue_struct outq;
40         outq.queue = NULL;
41         outq.nr = outq.alloc = 0;
42
43         if (opts & DIFF_PICKAXE_ALL) {
44                 /* Showing the whole changeset if needle exists */
45                 for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
46                         struct diff_filepair *p = q->queue[i];
47                         if (!DIFF_FILE_VALID(p->one)) {
48                                 if (!DIFF_FILE_VALID(p->two))
49                                         continue; /* ignore unmerged */
50                                 /* created */
51                                 if (contains(p->two, needle, len))
52                                         has_changes++;
53                         }
54                         else if (!DIFF_FILE_VALID(p->two)) {
55                                 if (contains(p->one, needle, len))
56                                         has_changes++;
57                         }
58                         else if (!diff_unmodified_pair(p) &&
59                                  contains(p->one, needle, len) !=
60                                  contains(p->two, needle, len))
61                                 has_changes++;
62                 }
63                 if (has_changes)
64                         return; /* not munge the queue */
65
66                 /* otherwise we will clear the whole queue
67                  * by copying the empty outq at the end of this
68                  * function, but first clear the current entries
69                  * in the queue.
70                  */
71                 for (i = 0; i < q->nr; i++)
72                         diff_free_filepair(q->queue[i]);
73         }
74         else 
75                 /* Showing only the filepairs that has the needle */
76                 for (i = 0; i < q->nr; i++) {
77                         struct diff_filepair *p = q->queue[i];
78                         has_changes = 0;
79                         if (!DIFF_FILE_VALID(p->one)) {
80                                 if (!DIFF_FILE_VALID(p->two))
81                                         ; /* ignore unmerged */
82                                 /* created */
83                                 else if (contains(p->two, needle, len))
84                                         has_changes = 1;
85                         }
86                         else if (!DIFF_FILE_VALID(p->two)) {
87                                 if (contains(p->one, needle, len))
88                                         has_changes = 1;
89                         }
90                         else if (!diff_unmodified_pair(p) &&
91                                  contains(p->one, needle, len) !=
92                                  contains(p->two, needle, len))
93                                 has_changes = 1;
94
95                         if (has_changes)
96                                 diff_q(&outq, p);
97                         else
98                                 diff_free_filepair(p);
99                 }
100
101         free(q->queue);
102         *q = outq;
103         return;
104 }