tree.c

   1 #include "cache.h"
   2 #include "tree.h"
   3 #include "blob.h"
   4 #include "commit.h"
   5 #include "tag.h"
   6 #include "tree-walk.h"
   7
   8 const char *tree_type = "tree";
   9
  10 static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
  11 {
  12         int len;
  13         unsigned int size;
  14         struct cache_entry *ce;
  15
  16         if (S_ISDIR(mode))
  17                 return READ_TREE_RECURSIVE;
  18
  19         len = strlen(pathname);
  20         size = cache_entry_size(baselen + len);
  21         ce = xcalloc(1, size);
  22
  23         ce->ce_mode = create_ce_mode(mode);
  24         ce->ce_flags = create_ce_flags(baselen + len, stage);
  25         memcpy(ce->name, base, baselen);
  26         memcpy(ce->name + baselen, pathname, len+1);
  27         hashcpy(ce->sha1, sha1);
  28         return add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
  29 }
  30
  31 static int match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
  32 {
  33         const char *match;
  34         int pathlen;
  35
  36         if (!paths)
  37                 return 1;
  38         pathlen = strlen(path);
  39         while ((match = *paths++) != NULL) {
  40                 int matchlen = strlen(match);
  41
  42                 if (baselen >= matchlen) {
  43                         /* If it doesn't match, move along... */
  44                         if (strncmp(base, match, matchlen))
  45                                 continue;
  46                         /* The base is a subdirectory of a path which was specified. */
  47                         return 1;
  48                 }
  49
  50                 /* Does the base match? */
  51                 if (strncmp(base, match, baselen))
  52                         continue;
  53
  54                 match += baselen;
  55                 matchlen -= baselen;
  56
  57                 if (pathlen > matchlen)
  58                         continue;
  59
  60                 if (matchlen > pathlen) {
  61                         if (match[pathlen] != '/')
  62                                 continue;
  63                         if (!S_ISDIR(mode))
  64                                 continue;
  65                 }
  66
  67                 if (strncmp(path, match, pathlen))
  68                         continue;
  69
  70                 return 1;
  71         }
  72         return 0;
  73 }
  74
  75 int read_tree_recursive(struct tree *tree,
  76                         const char *base, int baselen,
  77                         int stage, const char **match,
  78                         read_tree_fn_t fn)
  79 {
  80         struct tree_desc desc;
  81         struct name_entry entry;
  82
  83         if (parse_tree(tree))
  84                 return -1;
  85
  86         init_tree_desc(&desc, tree->buffer, tree->size);
  87
  88         while (tree_entry(&desc, &entry)) {
  89                 if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
  90                         continue;
  91
  92                 switch (fn(entry.sha1, base, baselen, entry.path, entry.mode, stage)) {
  93                 case 0:
  94                         continue;
  95                 case READ_TREE_RECURSIVE:
  96                         break;;
  97                 default:
  98                         return -1;
  99                 }
 100                 if (S_ISDIR(entry.mode)) {
 101                         int retval;
 102                         char *newbase;
 103                         unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
 104
 105                         newbase = xmalloc(baselen + 1 + pathlen);
 106                         memcpy(newbase, base, baselen);
 107                         memcpy(newbase + baselen, entry.path, pathlen);
 108                         newbase[baselen + pathlen] = '/';
 109                         retval = read_tree_recursive(lookup_tree(entry.sha1),
 110                                                      newbase,
 111                                                      baselen + pathlen + 1,
 112                                                      stage, match, fn);
 113                         free(newbase);
 114                         if (retval)
 115                                 return -1;
 116                         continue;
 117                 }
 118         }
 119         return 0;
 120 }
 121
 122 int read_tree(struct tree *tree, int stage, const char **match)
 123 {
 124         return read_tree_recursive(tree, "", 0, stage, match, read_one_entry);
 125 }
 126
 127 struct tree *lookup_tree(const unsigned char *sha1)
 128 {
 129         struct object *obj = lookup_object(sha1);
 130         if (!obj) {
 131                 struct tree *ret = alloc_tree_node();
 132                 created_object(sha1, &ret->object);
 133                 ret->object.type = OBJ_TREE;
 134                 return ret;
 135         }
 136         if (!obj->type)
 137                 obj->type = OBJ_TREE;
 138         if (obj->type != OBJ_TREE) {
 139                 error("Object %s is a %s, not a tree",
 140                       sha1_to_hex(sha1), typename(obj->type));
 141                 return NULL;
 142         }
 143         return (struct tree *) obj;
 144 }
 145
 146 /*
 147  * NOTE! Tree refs to external git repositories
 148  * (ie gitlinks) do not count as real references.
 149  *
 150  * You don't have to have those repositories
 151  * available at all, much less have the objects
 152  * accessible from the current repository.
 153  */
 154 static void track_tree_refs(struct tree *item)
 155 {
 156         int n_refs = 0, i;
 157         struct object_refs *refs;
 158         struct tree_desc desc;
 159         struct name_entry entry;
 160
 161         /* Count how many entries there are.. */
 162         init_tree_desc(&desc, item->buffer, item->size);
 163         while (tree_entry(&desc, &entry)) {
 164                 if (S_ISDIRLNK(entry.mode))
 165                         continue;
 166                 n_refs++;
 167         }
 168
 169         /* Allocate object refs and walk it again.. */
 170         i = 0;
 171         refs = alloc_object_refs(n_refs);
 172         init_tree_desc(&desc, item->buffer, item->size);
 173         while (tree_entry(&desc, &entry)) {
 174                 struct object *obj;
 175
 176                 if (S_ISDIRLNK(entry.mode))
 177                         continue;
 178                 if (S_ISDIR(entry.mode))
 179                         obj = &lookup_tree(entry.sha1)->object;
 180                 else
 181                         obj = &lookup_blob(entry.sha1)->object;
 182                 refs->ref[i++] = obj;
 183         }
 184         set_object_refs(&item->object, refs);
 185 }
 186
 187 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 188 {
 189         if (item->object.parsed)
 190                 return 0;
 191         item->object.parsed = 1;
 192         item->buffer = buffer;
 193         item->size = size;
 194
 195         if (track_object_refs)
 196                 track_tree_refs(item);
 197         return 0;
 198 }
 199
 200 int parse_tree(struct tree *item)
 201 {
 202          enum object_type type;
 203          void *buffer;
 204          unsigned long size;
 205
 206         if (item->object.parsed)
 207                 return 0;
 208         buffer = read_sha1_file(item->object.sha1, &type, &size);
 209         if (!buffer)
 210                 return error("Could not read %s",
 211                              sha1_to_hex(item->object.sha1));
 212         if (type != OBJ_TREE) {
 213                 free(buffer);
 214                 return error("Object %s not a tree",
 215                              sha1_to_hex(item->object.sha1));
 216         }
 217         return parse_tree_buffer(item, buffer, size);
 218 }
 219
 220 struct tree *parse_tree_indirect(const unsigned char *sha1)
 221 {
 222         struct object *obj = parse_object(sha1);
 223         do {
 224                 if (!obj)
 225                         return NULL;
 226                 if (obj->type == OBJ_TREE)
 227                         return (struct tree *) obj;
 228                 else if (obj->type == OBJ_COMMIT)
 229                         obj = &(((struct commit *) obj)->tree->object);
 230                 else if (obj->type == OBJ_TAG)
 231                         obj = ((struct tag *) obj)->tagged;
 232                 else
 233                         return NULL;
 234                 if (!obj->parsed)
 235                         parse_object(obj->sha1);
 236         } while (1);
 237 }