aboutsummaryrefslogtreecommitdiff
path: root/rev-tree.c
blob: 95ec274fc7fa68d2e70446104c51732ac7815fe2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
#include "cache.h"
#include "commit.h"

/*
 * revision.h leaves the low 16 bits of the "flags" field of the
 * revision data structure unused. We use it for a "reachable from
 * this commit <N>" bitmask.
 */
#define MAX_COMMITS 16

static int show_edges = 0;
static int basemask = 0;

static void read_cache_file(const char *path)
{
	die("no revtree cache file yet");
}

/*
 * Some revisions are less interesting than others.
 *
 * For example, if we use a cache-file, that one may contain
 * revisions that were never used. They are never interesting.
 *
 * And sometimes we're only interested in "edge" commits, ie
 * places where the marking changes between parent and child.
 */
static int interesting(struct commit *rev)
{
	unsigned mask = rev->object.flags;

	if (!mask)
		return 0;
	if (show_edges) {
		struct commit_list *p = rev->parents;
		while (p) {
			if (mask != p->item->object.flags)
				return 1;
			p = p->next;
		}
		return 0;
	}
	if (mask & basemask)
		return 0;

	return 1;
}

void process_commit(unsigned char *sha1)
{
	struct commit_list *parents;
	struct commit *obj = lookup_commit(sha1);

	if (obj->object.parsed)
		return;

	parse_commit(obj);
	
	parents = obj->parents;
	while (parents) {
		process_commit(parents->item->object.sha1);
		parents = parents->next;
	}
}

/*
 * Usage: rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id2>]
 *
 * The cache-file can be quite important for big trees. This is an
 * expensive operation if you have to walk the whole chain of
 * parents in a tree with a long revision history.
 */
int main(int argc, char **argv)
{
	int i;
	int nr = 0;
	unsigned char sha1[MAX_COMMITS][20];

	/*
	 * First - pick up all the revisions we can (both from
	 * caches and from commit file chains).
	 */
	for (i = 1; i < argc ; i++) {
		char *arg = argv[i];

		if (!strcmp(arg, "--cache")) {
			read_cache_file(argv[++i]);
			continue;
		}

		if (!strcmp(arg, "--edges")) {
			show_edges = 1;
			continue;
		}

		if (arg[0] == '^') {
			arg++;
			basemask |= 1<<nr;
		}
		if (nr >= MAX_COMMITS || get_sha1_hex(arg, sha1[nr]))
			usage("rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id>]");
		process_commit(sha1[nr]);
		nr++;
	}

	/*
	 * Now we have the maximal tree. Walk the different sha files back to the root.
	 */
	for (i = 0; i < nr; i++)
		mark_reachable(&lookup_commit(sha1[i])->object, 1 << i);

	/*
	 * Now print out the results..
	 */
	for (i = 0; i < nr_objs; i++) {
		struct object *obj = objs[i];
		struct commit *commit;
		struct commit_list *p;

		if (obj->type != commit_type)
			continue;

		commit = (struct commit *) obj;

		if (!interesting(commit))
			continue;

		printf("%lu %s:%d", commit->date, sha1_to_hex(obj->sha1), 
		       obj->flags);
		p = commit->parents;
		while (p) {
			printf(" %s:%d", sha1_to_hex(p->item->object.sha1), 
			       p->item->object.flags);
			p = p->next;
		}
		printf("\n");
	}
	return 0;
}