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, oldlen = base->len;
  56         enum interesting retval = entry_not_interesting;
  57
  58         if (parse_tree(tree))
  59                 return -1;
  60
  61         init_tree_desc(&desc, tree->buffer, tree->size);
  62
  63         while (tree_entry(&desc, &entry)) {
  64                 if (retval != all_entries_interesting) {
  65                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
  66                         if (retval == all_entries_not_interesting)
  67                                 break;
  68                         if (retval == entry_not_interesting)
  69                                 continue;
  70                 }
  71
  72                 switch (fn(entry.sha1, base->buf, base->len,
  73                            entry.path, entry.mode, stage, context)) {
  74                 case 0:
  75                         continue;
  76                 case READ_TREE_RECURSIVE:
  77                         break;
  78                 default:
  79                         return -1;
  80                 }
  81
  82                 if (S_ISDIR(entry.mode))
  83                         hashcpy(sha1, entry.sha1);
  84                 else if (S_ISGITLINK(entry.mode)) {
  85                         struct commit *commit;
  86
  87                         commit = lookup_commit(entry.sha1);
  88                         if (!commit)
  89                                 die("Commit %s in submodule path %s%s not found",
  90                                     sha1_to_hex(entry.sha1),
  91                                     base->buf, entry.path);
  92
  93                         if (parse_commit(commit))
  94                                 die("Invalid commit %s in submodule path %s%s",
  95                                     sha1_to_hex(entry.sha1),
  96                                     base->buf, entry.path);
  97
  98                         hashcpy(sha1, commit->tree->object.sha1);
  99                 }
 100                 else
 101                         continue;
 102
 103                 len = tree_entry_len(&entry);
 104                 strbuf_add(base, entry.path, len);
 105                 strbuf_addch(base, '/');
 106                 retval = read_tree_1(lookup_tree(sha1),
 107                                      base, stage, pathspec,
 108                                      fn, context);
 109                 strbuf_setlen(base, oldlen);
 110                 if (retval)
 111                         return -1;
 112         }
 113         return 0;
 114 }
 115
 116 int read_tree_recursive(struct tree *tree,
 117                         const char *base, int baselen,
 118                         int stage, struct pathspec *pathspec,
 119                         read_tree_fn_t fn, void *context)
 120 {
 121         struct strbuf sb = STRBUF_INIT;
 122         int ret;
 123
 124         strbuf_add(&sb, base, baselen);
 125         ret = read_tree_1(tree, &sb, stage, pathspec, fn, context);
 126         strbuf_release(&sb);
 127         return ret;
 128 }
 129
 130 static int cmp_cache_name_compare(const void *a_, const void *b_)
 131 {
 132         const struct cache_entry *ce1, *ce2;
 133
 134         ce1 = *((const struct cache_entry **)a_);
 135         ce2 = *((const struct cache_entry **)b_);
 136         return cache_name_compare(ce1->name, ce1->ce_flags,
 137                                   ce2->name, ce2->ce_flags);
 138 }
 139
 140 int read_tree(struct tree *tree, int stage, struct pathspec *match)
 141 {
 142         read_tree_fn_t fn = NULL;
 143         int i, err;
 144
 145         /*
 146          * Currently the only existing callers of this function all
 147          * call it with stage=1 and after making sure there is nothing
 148          * at that stage; we could always use read_one_entry_quick().
 149          *
 150          * But when we decide to straighten out git-read-tree not to
 151          * use unpack_trees() in some cases, this will probably start
 152          * to matter.
 153          */
 154
 155         /*
 156          * See if we have cache entry at the stage.  If so,
 157          * do it the original slow way, otherwise, append and then
 158          * sort at the end.
 159          */
 160         for (i = 0; !fn && i < active_nr; i++) {
 161                 struct cache_entry *ce = active_cache[i];
 162                 if (ce_stage(ce) == stage)
 163                         fn = read_one_entry;
 164         }
 165
 166         if (!fn)
 167                 fn = read_one_entry_quick;
 168         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
 169         if (fn == read_one_entry || err)
 170                 return err;
 171
 172         /*
 173          * Sort the cache entry -- we need to nuke the cache tree, though.
 174          */
 175         cache_tree_free(&active_cache_tree);
 176         qsort(active_cache, active_nr, sizeof(active_cache[0]),
 177               cmp_cache_name_compare);
 178         return 0;
 179 }
 180
 181 struct tree *lookup_tree(const unsigned char *sha1)
 182 {
 183         struct object *obj = lookup_object(sha1);
 184         if (!obj)
 185                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
 186         if (!obj->type)
 187                 obj->type = OBJ_TREE;
 188         if (obj->type != OBJ_TREE) {
 189                 error("Object %s is a %s, not a tree",
 190                       sha1_to_hex(sha1), typename(obj->type));
 191                 return NULL;
 192         }
 193         return (struct tree *) obj;
 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 struct tree *parse_tree_indirect(const unsigned char *sha1)
 228 {
 229         struct object *obj = parse_object(sha1);
 230         do {
 231                 if (!obj)
 232                         return NULL;
 233                 if (obj->type == OBJ_TREE)
 234                         return (struct tree *) obj;
 235                 else if (obj->type == OBJ_COMMIT)
 236                         obj = &(((struct commit *) obj)->tree->object);
 237                 else if (obj->type == OBJ_TAG)
 238                         obj = ((struct tag *) obj)->tagged;
 239                 else
 240                         return NULL;
 241                 if (!obj->parsed)
 242                         parse_object(obj->sha1);
 243         } while (1);
 244 }