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(baselen + len, stage);
  26         memcpy(ce->name, base, baselen);
  27         memcpy(ce->name + baselen, pathname, len+1);
  28         hashcpy(ce->sha1, sha1);
  29         return add_cache_entry(ce, opt);
  30 }
  31
  32 static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
  33 {
  34         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
  35                                   ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
  36 }
  37
  38 /*
  39  * This is used when the caller knows there is no existing entries at
  40  * the stage that will conflict with the entry being added.
  41  */
  42 static int read_one_entry_quick(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
  43 {
  44         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
  45                                   ADD_CACHE_JUST_APPEND);
  46 }
  47
  48 static int read_tree_1(struct tree *tree, struct strbuf *base,
  49                        int stage, struct pathspec *pathspec,
  50                        read_tree_fn_t fn, void *context)
  51 {
  52         struct tree_desc desc;
  53         struct name_entry entry;
  54         unsigned char sha1[20];
  55         int len, retval = 0, oldlen = base->len;
  56
  57         if (parse_tree(tree))
  58                 return -1;
  59
  60         init_tree_desc(&desc, tree->buffer, tree->size);
  61
  62         while (tree_entry(&desc, &entry)) {
  63                 if (retval != 2) {
  64                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
  65                         if (retval < 0)
  66                                 break;
  67                         if (retval == 0)
  68                                 continue;
  69                 }
  70
  71                 switch (fn(entry.sha1, base->buf, base->len,
  72                            entry.path, entry.mode, stage, context)) {
  73                 case 0:
  74                         continue;
  75                 case READ_TREE_RECURSIVE:
  76                         break;
  77                 default:
  78                         return -1;
  79                 }
  80
  81                 if (S_ISDIR(entry.mode))
  82                         hashcpy(sha1, entry.sha1);
  83                 else if (S_ISGITLINK(entry.mode)) {
  84                         struct commit *commit;
  85
  86                         commit = lookup_commit(entry.sha1);
  87                         if (!commit)
  88                                 die("Commit %s in submodule path %s%s not found",
  89                                     sha1_to_hex(entry.sha1),
  90                                     base->buf, entry.path);
  91
  92                         if (parse_commit(commit))
  93                                 die("Invalid commit %s in submodule path %s%s",
  94                                     sha1_to_hex(entry.sha1),
  95                                     base->buf, entry.path);
  96
  97                         hashcpy(sha1, commit->tree->object.sha1);
  98                 }
  99                 else
 100                         continue;
 101
 102                 len = tree_entry_len(entry.path, entry.sha1);
 103                 strbuf_add(base, entry.path, len);
 104                 strbuf_addch(base, '/');
 105                 retval = read_tree_1(lookup_tree(sha1),
 106                                      base, stage, pathspec,
 107                                      fn, context);
 108                 strbuf_setlen(base, oldlen);
 109                 if (retval)
 110                         return -1;
 111         }
 112         return 0;
 113 }
 114
 115 int read_tree_recursive(struct tree *tree,
 116                         const char *base, int baselen,
 117                         int stage, const char **match,
 118                         read_tree_fn_t fn, void *context)
 119 {
 120         struct strbuf sb = STRBUF_INIT;
 121         struct pathspec pathspec;
 122         int i, ret;
 123
 124         init_pathspec(&pathspec, match);
 125         for (i = 0; i < pathspec.nr; i++)
 126                 pathspec.items[i].has_wildcard = 0;
 127         strbuf_add(&sb, base, baselen);
 128         ret = read_tree_1(tree, &sb, stage, &pathspec, fn, context);
 129         strbuf_release(&sb);
 130         free_pathspec(&pathspec);
 131         return ret;
 132 }
 133
 134 static int cmp_cache_name_compare(const void *a_, const void *b_)
 135 {
 136         const struct cache_entry *ce1, *ce2;
 137
 138         ce1 = *((const struct cache_entry **)a_);
 139         ce2 = *((const struct cache_entry **)b_);
 140         return cache_name_compare(ce1->name, ce1->ce_flags,
 141                                   ce2->name, ce2->ce_flags);
 142 }
 143
 144 int read_tree(struct tree *tree, int stage, const char **match)
 145 {
 146         read_tree_fn_t fn = NULL;
 147         int i, err;
 148
 149         /*
 150          * Currently the only existing callers of this function all
 151          * call it with stage=1 and after making sure there is nothing
 152          * at that stage; we could always use read_one_entry_quick().
 153          *
 154          * But when we decide to straighten out git-read-tree not to
 155          * use unpack_trees() in some cases, this will probably start
 156          * to matter.
 157          */
 158
 159         /*
 160          * See if we have cache entry at the stage.  If so,
 161          * do it the original slow way, otherwise, append and then
 162          * sort at the end.
 163          */
 164         for (i = 0; !fn && i < active_nr; i++) {
 165                 struct cache_entry *ce = active_cache[i];
 166                 if (ce_stage(ce) == stage)
 167                         fn = read_one_entry;
 168         }
 169
 170         if (!fn)
 171                 fn = read_one_entry_quick;
 172         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
 173         if (fn == read_one_entry || err)
 174                 return err;
 175
 176         /*
 177          * Sort the cache entry -- we need to nuke the cache tree, though.
 178          */
 179         cache_tree_free(&active_cache_tree);
 180         qsort(active_cache, active_nr, sizeof(active_cache[0]),
 181               cmp_cache_name_compare);
 182         return 0;
 183 }
 184
 185 struct tree *lookup_tree(const unsigned char *sha1)
 186 {
 187         struct object *obj = lookup_object(sha1);
 188         if (!obj)
 189                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
 190         if (!obj->type)
 191                 obj->type = OBJ_TREE;
 192         if (obj->type != OBJ_TREE) {
 193                 error("Object %s is a %s, not a tree",
 194                       sha1_to_hex(sha1), typename(obj->type));
 195                 return NULL;
 196         }
 197         return (struct tree *) obj;
 198 }
 199
 200 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 201 {
 202         if (item->object.parsed)
 203                 return 0;
 204         item->object.parsed = 1;
 205         item->buffer = buffer;
 206         item->size = size;
 207
 208         return 0;
 209 }
 210
 211 int parse_tree(struct tree *item)
 212 {
 213          enum object_type type;
 214          void *buffer;
 215          unsigned long size;
 216
 217         if (item->object.parsed)
 218                 return 0;
 219         buffer = read_sha1_file(item->object.sha1, &type, &size);
 220         if (!buffer)
 221                 return error("Could not read %s",
 222                              sha1_to_hex(item->object.sha1));
 223         if (type != OBJ_TREE) {
 224                 free(buffer);
 225                 return error("Object %s not a tree",
 226                              sha1_to_hex(item->object.sha1));
 227         }
 228         return parse_tree_buffer(item, buffer, size);
 229 }
 230
 231 struct tree *parse_tree_indirect(const unsigned char *sha1)
 232 {
 233         struct object *obj = parse_object(sha1);
 234         do {
 235                 if (!obj)
 236                         return NULL;
 237                 if (obj->type == OBJ_TREE)
 238                         return (struct tree *) obj;
 239                 else if (obj->type == OBJ_COMMIT)
 240                         obj = &(((struct commit *) obj)->tree->object);
 241                 else if (obj->type == OBJ_TAG)
 242                         obj = ((struct tag *) obj)->tagged;
 243                 else
 244                         return NULL;
 245                 if (!obj->parsed)
 246                         parse_object(obj->sha1);
 247         } while (1);
 248 }