t7201.24: Add refspec to keep --track working
[git] / tree.c
1 #include "cache.h"
2 #include "cache-tree.h"
3 #include "tree.h"
4 #include "blob.h"
5 #include "commit.h"
6 #include "tag.h"
7 #include "tree-walk.h"
8
9 const char *tree_type = "tree";
10
11 static int read_one_entry_opt(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, int opt)
12 {
13         int len;
14         unsigned int size;
15         struct cache_entry *ce;
16
17         if (S_ISDIR(mode))
18                 return READ_TREE_RECURSIVE;
19
20         len = strlen(pathname);
21         size = cache_entry_size(baselen + len);
22         ce = xcalloc(1, size);
23
24         ce->ce_mode = create_ce_mode(mode);
25         ce->ce_flags = create_ce_flags(stage);
26         ce->ce_namelen = baselen + len;
27         memcpy(ce->name, base, baselen);
28         memcpy(ce->name + baselen, pathname, len+1);
29         hashcpy(ce->sha1, sha1);
30         return add_cache_entry(ce, opt);
31 }
32
33 static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
34 {
35         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
36                                   ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
37 }
38
39 /*
40  * This is used when the caller knows there is no existing entries at
41  * the stage that will conflict with the entry being added.
42  */
43 static int read_one_entry_quick(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
44 {
45         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
46                                   ADD_CACHE_JUST_APPEND);
47 }
48
49 static int read_tree_1(struct tree *tree, struct strbuf *base,
50                        int stage, struct pathspec *pathspec,
51                        read_tree_fn_t fn, void *context)
52 {
53         struct tree_desc desc;
54         struct name_entry entry;
55         unsigned char sha1[20];
56         int len, oldlen = base->len;
57         enum interesting retval = entry_not_interesting;
58
59         if (parse_tree(tree))
60                 return -1;
61
62         init_tree_desc(&desc, tree->buffer, tree->size);
63
64         while (tree_entry(&desc, &entry)) {
65                 if (retval != all_entries_interesting) {
66                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
67                         if (retval == all_entries_not_interesting)
68                                 break;
69                         if (retval == entry_not_interesting)
70                                 continue;
71                 }
72
73                 switch (fn(entry.sha1, base->buf, base->len,
74                            entry.path, entry.mode, stage, context)) {
75                 case 0:
76                         continue;
77                 case READ_TREE_RECURSIVE:
78                         break;
79                 default:
80                         return -1;
81                 }
82
83                 if (S_ISDIR(entry.mode))
84                         hashcpy(sha1, entry.sha1);
85                 else if (S_ISGITLINK(entry.mode)) {
86                         struct commit *commit;
87
88                         commit = lookup_commit(entry.sha1);
89                         if (!commit)
90                                 die("Commit %s in submodule path %s%s not found",
91                                     sha1_to_hex(entry.sha1),
92                                     base->buf, entry.path);
93
94                         if (parse_commit(commit))
95                                 die("Invalid commit %s in submodule path %s%s",
96                                     sha1_to_hex(entry.sha1),
97                                     base->buf, entry.path);
98
99                         hashcpy(sha1, commit->tree->object.sha1);
100                 }
101                 else
102                         continue;
103
104                 len = tree_entry_len(&entry);
105                 strbuf_add(base, entry.path, len);
106                 strbuf_addch(base, '/');
107                 retval = read_tree_1(lookup_tree(sha1),
108                                      base, stage, pathspec,
109                                      fn, context);
110                 strbuf_setlen(base, oldlen);
111                 if (retval)
112                         return -1;
113         }
114         return 0;
115 }
116
117 int read_tree_recursive(struct tree *tree,
118                         const char *base, int baselen,
119                         int stage, struct pathspec *pathspec,
120                         read_tree_fn_t fn, void *context)
121 {
122         struct strbuf sb = STRBUF_INIT;
123         int ret;
124
125         strbuf_add(&sb, base, baselen);
126         ret = read_tree_1(tree, &sb, stage, pathspec, fn, context);
127         strbuf_release(&sb);
128         return ret;
129 }
130
131 static int cmp_cache_name_compare(const void *a_, const void *b_)
132 {
133         const struct cache_entry *ce1, *ce2;
134
135         ce1 = *((const struct cache_entry **)a_);
136         ce2 = *((const struct cache_entry **)b_);
137         return cache_name_stage_compare(ce1->name, ce1->ce_namelen, ce_stage(ce1),
138                                   ce2->name, ce2->ce_namelen, ce_stage(ce2));
139 }
140
141 int read_tree(struct tree *tree, int stage, struct pathspec *match)
142 {
143         read_tree_fn_t fn = NULL;
144         int i, err;
145
146         /*
147          * Currently the only existing callers of this function all
148          * call it with stage=1 and after making sure there is nothing
149          * at that stage; we could always use read_one_entry_quick().
150          *
151          * But when we decide to straighten out git-read-tree not to
152          * use unpack_trees() in some cases, this will probably start
153          * to matter.
154          */
155
156         /*
157          * See if we have cache entry at the stage.  If so,
158          * do it the original slow way, otherwise, append and then
159          * sort at the end.
160          */
161         for (i = 0; !fn && i < active_nr; i++) {
162                 struct cache_entry *ce = active_cache[i];
163                 if (ce_stage(ce) == stage)
164                         fn = read_one_entry;
165         }
166
167         if (!fn)
168                 fn = read_one_entry_quick;
169         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
170         if (fn == read_one_entry || err)
171                 return err;
172
173         /*
174          * Sort the cache entry -- we need to nuke the cache tree, though.
175          */
176         cache_tree_free(&active_cache_tree);
177         qsort(active_cache, active_nr, sizeof(active_cache[0]),
178               cmp_cache_name_compare);
179         return 0;
180 }
181
182 struct tree *lookup_tree(const unsigned char *sha1)
183 {
184         struct object *obj = lookup_object(sha1);
185         if (!obj)
186                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
187         if (!obj->type)
188                 obj->type = OBJ_TREE;
189         if (obj->type != OBJ_TREE) {
190                 error("Object %s is a %s, not a tree",
191                       sha1_to_hex(sha1), typename(obj->type));
192                 return NULL;
193         }
194         return (struct tree *) obj;
195 }
196
197 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
198 {
199         if (item->object.parsed)
200                 return 0;
201         item->object.parsed = 1;
202         item->buffer = buffer;
203         item->size = size;
204
205         return 0;
206 }
207
208 int parse_tree(struct tree *item)
209 {
210          enum object_type type;
211          void *buffer;
212          unsigned long size;
213
214         if (item->object.parsed)
215                 return 0;
216         buffer = read_sha1_file(item->object.sha1, &type, &size);
217         if (!buffer)
218                 return error("Could not read %s",
219                              sha1_to_hex(item->object.sha1));
220         if (type != OBJ_TREE) {
221                 free(buffer);
222                 return error("Object %s not a tree",
223                              sha1_to_hex(item->object.sha1));
224         }
225         return parse_tree_buffer(item, buffer, size);
226 }
227
228 struct tree *parse_tree_indirect(const unsigned char *sha1)
229 {
230         struct object *obj = parse_object(sha1);
231         do {
232                 if (!obj)
233                         return NULL;
234                 if (obj->type == OBJ_TREE)
235                         return (struct tree *) obj;
236                 else if (obj->type == OBJ_COMMIT)
237                         obj = &(((struct commit *) obj)->tree->object);
238                 else if (obj->type == OBJ_TAG)
239                         obj = ((struct tag *) obj)->tagged;
240                 else
241                         return NULL;
242                 if (!obj->parsed)
243                         parse_object(obj->sha1);
244         } while (1);
245 }