contrib/git-svn: handle array values correctly
[git/git.git] / tree-walk.c
CommitLineData
1b0c7174
JH
1#include "cache.h"
2#include "tree-walk.h"
3
4void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
5{
6 unsigned long size = 0;
7 void *buf = NULL;
8
9 if (sha1) {
10 buf = read_object_with_reference(sha1, "tree", &size, NULL);
11 if (!buf)
12 die("unable to read tree %s", sha1_to_hex(sha1));
13 }
14 desc->size = size;
15 desc->buf = buf;
16 return buf;
17}
18
19static int entry_compare(struct name_entry *a, struct name_entry *b)
20{
21 return base_name_compare(
22 a->path, a->pathlen, a->mode,
23 b->path, b->pathlen, b->mode);
24}
25
26static void entry_clear(struct name_entry *a)
27{
28 memset(a, 0, sizeof(*a));
29}
30
31static void entry_extract(struct tree_desc *t, struct name_entry *a)
32{
33 a->sha1 = tree_entry_extract(t, &a->path, &a->mode);
34 a->pathlen = strlen(a->path);
35}
36
37void update_tree_entry(struct tree_desc *desc)
38{
39 void *buf = desc->buf;
40 unsigned long size = desc->size;
41 int len = strlen(buf) + 1 + 20;
42
43 if (size < len)
44 die("corrupt tree file");
45 desc->buf = buf + len;
46 desc->size = size - len;
47}
48
49const unsigned char *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
50{
51 void *tree = desc->buf;
52 unsigned long size = desc->size;
53 int len = strlen(tree)+1;
54 const unsigned char *sha1 = tree + len;
55 const char *path = strchr(tree, ' ');
56 unsigned int mode;
57
58 if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
59 die("corrupt tree file");
60 *pathp = path+1;
61 *modep = canon_mode(mode);
62 return sha1;
63}
64
65void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback)
66{
67 struct name_entry *entry = xmalloc(n*sizeof(*entry));
68
69 for (;;) {
70 struct name_entry entry[3];
71 unsigned long mask = 0;
72 int i, last;
73
74 last = -1;
75 for (i = 0; i < n; i++) {
76 if (!t[i].size)
77 continue;
78 entry_extract(t+i, entry+i);
79 if (last >= 0) {
80 int cmp = entry_compare(entry+i, entry+last);
81
82 /*
83 * Is the new name bigger than the old one?
84 * Ignore it
85 */
86 if (cmp > 0)
87 continue;
88 /*
89 * Is the new name smaller than the old one?
90 * Ignore all old ones
91 */
92 if (cmp < 0)
93 mask = 0;
94 }
95 mask |= 1ul << i;
96 last = i;
97 }
98 if (!mask)
99 break;
100
101 /*
102 * Update the tree entries we've walked, and clear
103 * all the unused name-entries.
104 */
105 for (i = 0; i < n; i++) {
106 if (mask & (1ul << i)) {
107 update_tree_entry(t+i);
108 continue;
109 }
110 entry_clear(entry + i);
111 }
112 callback(n, mask, entry, base);
113 }
114 free(entry);
115}
116