remove unnecessary check before QSORT
[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->oid.hash, sha1);
30         return add_cache_entry(ce, opt);
31 }
32
33 static int read_one_entry(const unsigned char *sha1, struct strbuf *base,
34                           const char *pathname, unsigned mode, int stage,
35                           void *context)
36 {
37         return read_one_entry_opt(sha1, base->buf, base->len, pathname,
38                                   mode, stage,
39                                   ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
40 }
41
42 /*
43  * This is used when the caller knows there is no existing entries at
44  * the stage that will conflict with the entry being added.
45  */
46 static int read_one_entry_quick(const unsigned char *sha1, struct strbuf *base,
47                                 const char *pathname, unsigned mode, int stage,
48                                 void *context)
49 {
50         return read_one_entry_opt(sha1, base->buf, base->len, pathname,
51                                   mode, stage,
52                                   ADD_CACHE_JUST_APPEND);
53 }
54
55 static int read_tree_1(struct tree *tree, struct strbuf *base,
56                        int stage, const struct pathspec *pathspec,
57                        read_tree_fn_t fn, void *context)
58 {
59         struct tree_desc desc;
60         struct name_entry entry;
61         unsigned char sha1[20];
62         int len, oldlen = base->len;
63         enum interesting retval = entry_not_interesting;
64
65         if (parse_tree(tree))
66                 return -1;
67
68         init_tree_desc(&desc, tree->buffer, tree->size);
69
70         while (tree_entry(&desc, &entry)) {
71                 if (retval != all_entries_interesting) {
72                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
73                         if (retval == all_entries_not_interesting)
74                                 break;
75                         if (retval == entry_not_interesting)
76                                 continue;
77                 }
78
79                 switch (fn(entry.oid->hash, base,
80                            entry.path, entry.mode, stage, context)) {
81                 case 0:
82                         continue;
83                 case READ_TREE_RECURSIVE:
84                         break;
85                 default:
86                         return -1;
87                 }
88
89                 if (S_ISDIR(entry.mode))
90                         hashcpy(sha1, entry.oid->hash);
91                 else if (S_ISGITLINK(entry.mode)) {
92                         struct commit *commit;
93
94                         commit = lookup_commit(entry.oid->hash);
95                         if (!commit)
96                                 die("Commit %s in submodule path %s%s not found",
97                                     oid_to_hex(entry.oid),
98                                     base->buf, entry.path);
99
100                         if (parse_commit(commit))
101                                 die("Invalid commit %s in submodule path %s%s",
102                                     oid_to_hex(entry.oid),
103                                     base->buf, entry.path);
104
105                         hashcpy(sha1, commit->tree->object.oid.hash);
106                 }
107                 else
108                         continue;
109
110                 len = tree_entry_len(&entry);
111                 strbuf_add(base, entry.path, len);
112                 strbuf_addch(base, '/');
113                 retval = read_tree_1(lookup_tree(sha1),
114                                      base, stage, pathspec,
115                                      fn, context);
116                 strbuf_setlen(base, oldlen);
117                 if (retval)
118                         return -1;
119         }
120         return 0;
121 }
122
123 int read_tree_recursive(struct tree *tree,
124                         const char *base, int baselen,
125                         int stage, const struct pathspec *pathspec,
126                         read_tree_fn_t fn, void *context)
127 {
128         struct strbuf sb = STRBUF_INIT;
129         int ret;
130
131         strbuf_add(&sb, base, baselen);
132         ret = read_tree_1(tree, &sb, stage, pathspec, fn, context);
133         strbuf_release(&sb);
134         return ret;
135 }
136
137 static int cmp_cache_name_compare(const void *a_, const void *b_)
138 {
139         const struct cache_entry *ce1, *ce2;
140
141         ce1 = *((const struct cache_entry **)a_);
142         ce2 = *((const struct cache_entry **)b_);
143         return cache_name_stage_compare(ce1->name, ce1->ce_namelen, ce_stage(ce1),
144                                   ce2->name, ce2->ce_namelen, ce_stage(ce2));
145 }
146
147 int read_tree(struct tree *tree, int stage, struct pathspec *match)
148 {
149         read_tree_fn_t fn = NULL;
150         int i, err;
151
152         /*
153          * Currently the only existing callers of this function all
154          * call it with stage=1 and after making sure there is nothing
155          * at that stage; we could always use read_one_entry_quick().
156          *
157          * But when we decide to straighten out git-read-tree not to
158          * use unpack_trees() in some cases, this will probably start
159          * to matter.
160          */
161
162         /*
163          * See if we have cache entry at the stage.  If so,
164          * do it the original slow way, otherwise, append and then
165          * sort at the end.
166          */
167         for (i = 0; !fn && i < active_nr; i++) {
168                 const struct cache_entry *ce = active_cache[i];
169                 if (ce_stage(ce) == stage)
170                         fn = read_one_entry;
171         }
172
173         if (!fn)
174                 fn = read_one_entry_quick;
175         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
176         if (fn == read_one_entry || err)
177                 return err;
178
179         /*
180          * Sort the cache entry -- we need to nuke the cache tree, though.
181          */
182         cache_tree_free(&active_cache_tree);
183         QSORT(active_cache, active_nr, cmp_cache_name_compare);
184         return 0;
185 }
186
187 struct tree *lookup_tree(const unsigned char *sha1)
188 {
189         struct object *obj = lookup_object(sha1);
190         if (!obj)
191                 return create_object(sha1, alloc_tree_node());
192         return object_as_type(obj, OBJ_TREE, 0);
193 }
194
195 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
196 {
197         if (item->object.parsed)
198                 return 0;
199         item->object.parsed = 1;
200         item->buffer = buffer;
201         item->size = size;
202
203         return 0;
204 }
205
206 int parse_tree_gently(struct tree *item, int quiet_on_missing)
207 {
208          enum object_type type;
209          void *buffer;
210          unsigned long size;
211
212         if (item->object.parsed)
213                 return 0;
214         buffer = read_sha1_file(item->object.oid.hash, &type, &size);
215         if (!buffer)
216                 return quiet_on_missing ? -1 :
217                         error("Could not read %s",
218                              oid_to_hex(&item->object.oid));
219         if (type != OBJ_TREE) {
220                 free(buffer);
221                 return error("Object %s not a tree",
222                              oid_to_hex(&item->object.oid));
223         }
224         return parse_tree_buffer(item, buffer, size);
225 }
226
227 void free_tree_buffer(struct tree *tree)
228 {
229         free(tree->buffer);
230         tree->buffer = NULL;
231         tree->size = 0;
232         tree->object.parsed = 0;
233 }
234
235 struct tree *parse_tree_indirect(const unsigned char *sha1)
236 {
237         struct object *obj = parse_object(sha1);
238         do {
239                 if (!obj)
240                         return NULL;
241                 if (obj->type == OBJ_TREE)
242                         return (struct tree *) obj;
243                 else if (obj->type == OBJ_COMMIT)
244                         obj = &(((struct commit *) obj)->tree->object);
245                 else if (obj->type == OBJ_TAG)
246                         obj = ((struct tag *) obj)->tagged;
247                 else
248                         return NULL;
249                 if (!obj->parsed)
250                         parse_object(obj->oid.hash);
251         } while (1);
252 }