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, 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.sha1, 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.sha1);
  91                 else if (S_ISGITLINK(entry.mode)) {
  92                         struct commit *commit;
  93
  94                         commit = lookup_commit(entry.sha1);
  95                         if (!commit)
  96                                 die("Commit %s in submodule path %s%s not found",
  97                                     sha1_to_hex(entry.sha1),
  98                                     base->buf, entry.path);
  99
 100                         if (parse_commit(commit))
 101                                 die("Invalid commit %s in submodule path %s%s",
 102                                     sha1_to_hex(entry.sha1),
 103                                     base->buf, entry.path);
 104
 105                         hashcpy(sha1, commit->tree->object.sha1);
 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, sizeof(active_cache[0]),
 184               cmp_cache_name_compare);
 185         return 0;
 186 }
 187
 188 struct tree *lookup_tree(const unsigned char *sha1)
 189 {
 190         struct object *obj = lookup_object(sha1);
 191         if (!obj)
 192                 return create_object(sha1, alloc_tree_node());
 193         return object_as_type(obj, OBJ_TREE, 0);
 194 }
 195
 196 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 197 {
 198         if (item->object.parsed)
 199                 return 0;
 200         item->object.parsed = 1;
 201         item->buffer = buffer;
 202         item->size = size;
 203
 204         return 0;
 205 }
 206
 207 int parse_tree(struct tree *item)
 208 {
 209          enum object_type type;
 210          void *buffer;
 211          unsigned long size;
 212
 213         if (item->object.parsed)
 214                 return 0;
 215         buffer = read_sha1_file(item->object.sha1, &type, &size);
 216         if (!buffer)
 217                 return error("Could not read %s",
 218                              sha1_to_hex(item->object.sha1));
 219         if (type != OBJ_TREE) {
 220                 free(buffer);
 221                 return error("Object %s not a tree",
 222                              sha1_to_hex(item->object.sha1));
 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->sha1);
 251         } while (1);
 252 }