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