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 match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
  49 {
  50         const char *match;
  51         int pathlen;
  52
  53         if (!paths)
  54                 return 1;
  55         pathlen = strlen(path);
  56         while ((match = *paths++) != NULL) {
  57                 int matchlen = strlen(match);
  58
  59                 if (baselen >= matchlen) {
  60                         /* If it doesn't match, move along... */
  61                         if (strncmp(base, match, matchlen))
  62                                 continue;
  63                         /* pathspecs match only at the directory boundaries */
  64                         if (!matchlen ||
  65                             baselen == matchlen ||
  66                             base[matchlen] == '/' ||
  67                             match[matchlen - 1] == '/')
  68                                 return 1;
  69                         continue;
  70                 }
  71
  72                 /* Does the base match? */
  73                 if (strncmp(base, match, baselen))
  74                         continue;
  75
  76                 match += baselen;
  77                 matchlen -= baselen;
  78
  79                 if (pathlen > matchlen)
  80                         continue;
  81
  82                 if (matchlen > pathlen) {
  83                         if (match[pathlen] != '/')
  84                                 continue;
  85                         if (!S_ISDIR(mode))
  86                                 continue;
  87                 }
  88
  89                 if (strncmp(path, match, pathlen))
  90                         continue;
  91
  92                 return 1;
  93         }
  94         return 0;
  95 }
  96
  97 int read_tree_recursive(struct tree *tree,
  98                         const char *base, int baselen,
  99                         int stage, const char **match,
 100                         read_tree_fn_t fn, void *context)
 101 {
 102         struct tree_desc desc;
 103         struct name_entry entry;
 104
 105         if (parse_tree(tree))
 106                 return -1;
 107
 108         init_tree_desc(&desc, tree->buffer, tree->size);
 109
 110         while (tree_entry(&desc, &entry)) {
 111                 if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
 112                         continue;
 113
 114                 switch (fn(entry.sha1, base, baselen, entry.path, entry.mode, stage, context)) {
 115                 case 0:
 116                         continue;
 117                 case READ_TREE_RECURSIVE:
 118                         break;
 119                 default:
 120                         return -1;
 121                 }
 122                 if (S_ISDIR(entry.mode)) {
 123                         int retval;
 124                         char *newbase;
 125                         unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
 126
 127                         newbase = xmalloc(baselen + 1 + pathlen);
 128                         memcpy(newbase, base, baselen);
 129                         memcpy(newbase + baselen, entry.path, pathlen);
 130                         newbase[baselen + pathlen] = '/';
 131                         retval = read_tree_recursive(lookup_tree(entry.sha1),
 132                                                      newbase,
 133                                                      baselen + pathlen + 1,
 134                                                      stage, match, fn, context);
 135                         free(newbase);
 136                         if (retval)
 137                                 return -1;
 138                         continue;
 139                 } else if (S_ISGITLINK(entry.mode)) {
 140                         int retval;
 141                         struct strbuf path;
 142                         unsigned int entrylen;
 143                         struct commit *commit;
 144
 145                         entrylen = tree_entry_len(entry.path, entry.sha1);
 146                         strbuf_init(&path, baselen + entrylen + 1);
 147                         strbuf_add(&path, base, baselen);
 148                         strbuf_add(&path, entry.path, entrylen);
 149                         strbuf_addch(&path, '/');
 150
 151                         commit = lookup_commit(entry.sha1);
 152                         if (!commit)
 153                                 die("Commit %s in submodule path %s not found",
 154                                     sha1_to_hex(entry.sha1), path.buf);
 155
 156                         if (parse_commit(commit))
 157                                 die("Invalid commit %s in submodule path %s",
 158                                     sha1_to_hex(entry.sha1), path.buf);
 159
 160                         retval = read_tree_recursive(commit->tree,
 161                                                      path.buf, path.len,
 162                                                      stage, match, fn, context);
 163                         strbuf_release(&path);
 164                         if (retval)
 165                                 return -1;
 166                         continue;
 167                 }
 168         }
 169         return 0;
 170 }
 171
 172 static int cmp_cache_name_compare(const void *a_, const void *b_)
 173 {
 174         const struct cache_entry *ce1, *ce2;
 175
 176         ce1 = *((const struct cache_entry **)a_);
 177         ce2 = *((const struct cache_entry **)b_);
 178         return cache_name_compare(ce1->name, ce1->ce_flags,
 179                                   ce2->name, ce2->ce_flags);
 180 }
 181
 182 int read_tree(struct tree *tree, int stage, const char **match)
 183 {
 184         read_tree_fn_t fn = NULL;
 185         int i, err;
 186
 187         /*
 188          * Currently the only existing callers of this function all
 189          * call it with stage=1 and after making sure there is nothing
 190          * at that stage; we could always use read_one_entry_quick().
 191          *
 192          * But when we decide to straighten out git-read-tree not to
 193          * use unpack_trees() in some cases, this will probably start
 194          * to matter.
 195          */
 196
 197         /*
 198          * See if we have cache entry at the stage.  If so,
 199          * do it the original slow way, otherwise, append and then
 200          * sort at the end.
 201          */
 202         for (i = 0; !fn && i < active_nr; i++) {
 203                 struct cache_entry *ce = active_cache[i];
 204                 if (ce_stage(ce) == stage)
 205                         fn = read_one_entry;
 206         }
 207
 208         if (!fn)
 209                 fn = read_one_entry_quick;
 210         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
 211         if (fn == read_one_entry || err)
 212                 return err;
 213
 214         /*
 215          * Sort the cache entry -- we need to nuke the cache tree, though.
 216          */
 217         cache_tree_free(&active_cache_tree);
 218         qsort(active_cache, active_nr, sizeof(active_cache[0]),
 219               cmp_cache_name_compare);
 220         return 0;
 221 }
 222
 223 struct tree *lookup_tree(const unsigned char *sha1)
 224 {
 225         struct object *obj = lookup_object(sha1);
 226         if (!obj)
 227                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
 228         if (!obj->type)
 229                 obj->type = OBJ_TREE;
 230         if (obj->type != OBJ_TREE) {
 231                 error("Object %s is a %s, not a tree",
 232                       sha1_to_hex(sha1), typename(obj->type));
 233                 return NULL;
 234         }
 235         return (struct tree *) obj;
 236 }
 237
 238 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 239 {
 240         if (item->object.parsed)
 241                 return 0;
 242         item->object.parsed = 1;
 243         item->buffer = buffer;
 244         item->size = size;
 245
 246         return 0;
 247 }
 248
 249 int parse_tree(struct tree *item)
 250 {
 251          enum object_type type;
 252          void *buffer;
 253          unsigned long size;
 254
 255         if (item->object.parsed)
 256                 return 0;
 257         buffer = read_sha1_file(item->object.sha1, &type, &size);
 258         if (!buffer)
 259                 return error("Could not read %s",
 260                              sha1_to_hex(item->object.sha1));
 261         if (type != OBJ_TREE) {
 262                 free(buffer);
 263                 return error("Object %s not a tree",
 264                              sha1_to_hex(item->object.sha1));
 265         }
 266         return parse_tree_buffer(item, buffer, size);
 267 }
 268
 269 struct tree *parse_tree_indirect(const unsigned char *sha1)
 270 {
 271         struct object *obj = parse_object(sha1);
 272         do {
 273                 if (!obj)
 274                         return NULL;
 275                 if (obj->type == OBJ_TREE)
 276                         return (struct tree *) obj;
 277                 else if (obj->type == OBJ_COMMIT)
 278                         obj = &(((struct commit *) obj)->tree->object);
 279                 else if (obj->type == OBJ_TAG)
 280                         obj = ((struct tag *) obj)->tagged;
 281                 else
 282                         return NULL;
 283                 if (!obj->parsed)
 284                         parse_object(obj->sha1);
 285         } while (1);
 286 }