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, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
  34 {
  35         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
  36                                   ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
  37 }
  38
  39 /*
  40  * This is used when the caller knows there is no existing entries at
  41  * the stage that will conflict with the entry being added.
  42  */
  43 static int read_one_entry_quick(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context)
  44 {
  45         return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
  46                                   ADD_CACHE_JUST_APPEND);
  47 }
  48
  49 static int read_tree_1(struct tree *tree, struct strbuf *base,
  50                        int stage, struct pathspec *pathspec,
  51                        read_tree_fn_t fn, void *context)
  52 {
  53         struct tree_desc desc;
  54         struct name_entry entry;
  55         unsigned char sha1[20];
  56         int len, oldlen = base->len;
  57         enum interesting retval = entry_not_interesting;
  58
  59         if (parse_tree(tree))
  60                 return -1;
  61
  62         init_tree_desc(&desc, tree->buffer, tree->size);
  63
  64         while (tree_entry(&desc, &entry)) {
  65                 if (retval != all_entries_interesting) {
  66                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
  67                         if (retval == all_entries_not_interesting)
  68                                 break;
  69                         if (retval == entry_not_interesting)
  70                                 continue;
  71                 }
  72
  73                 switch (fn(entry.sha1, base->buf, base->len,
  74                            entry.path, entry.mode, stage, context)) {
  75                 case 0:
  76                         continue;
  77                 case READ_TREE_RECURSIVE:
  78                         break;
  79                 default:
  80                         return -1;
  81                 }
  82
  83                 if (S_ISDIR(entry.mode))
  84                         hashcpy(sha1, entry.sha1);
  85                 else if (S_ISGITLINK(entry.mode)) {
  86                         struct commit *commit;
  87
  88                         commit = lookup_commit(entry.sha1);
  89                         if (!commit)
  90                                 die("Commit %s in submodule path %s%s not found",
  91                                     sha1_to_hex(entry.sha1),
  92                                     base->buf, entry.path);
  93
  94                         if (parse_commit(commit))
  95                                 die("Invalid commit %s in submodule path %s%s",
  96                                     sha1_to_hex(entry.sha1),
  97                                     base->buf, entry.path);
  98
  99                         hashcpy(sha1, commit->tree->object.sha1);
 100                 }
 101                 else
 102                         continue;
 103
 104                 len = tree_entry_len(&entry);
 105                 strbuf_add(base, entry.path, len);
 106                 strbuf_addch(base, '/');
 107                 retval = read_tree_1(lookup_tree(sha1),
 108                                      base, stage, pathspec,
 109                                      fn, context);
 110                 strbuf_setlen(base, oldlen);
 111                 if (retval)
 112                         return -1;
 113         }
 114         return 0;
 115 }
 116
 117 int read_tree_recursive(struct tree *tree,
 118                         const char *base, int baselen,
 119                         int stage, struct pathspec *pathspec,
 120                         read_tree_fn_t fn, void *context)
 121 {
 122         struct strbuf sb = STRBUF_INIT;
 123         int ret;
 124
 125         strbuf_add(&sb, base, baselen);
 126         ret = read_tree_1(tree, &sb, stage, pathspec, fn, context);
 127         strbuf_release(&sb);
 128         return ret;
 129 }
 130
 131 static int cmp_cache_name_compare(const void *a_, const void *b_)
 132 {
 133         const struct cache_entry *ce1, *ce2;
 134
 135         ce1 = *((const struct cache_entry **)a_);
 136         ce2 = *((const struct cache_entry **)b_);
 137         return cache_name_stage_compare(ce1->name, ce1->ce_namelen, ce_stage(ce1),
 138                                   ce2->name, ce2->ce_namelen, ce_stage(ce2));
 139 }
 140
 141 int read_tree(struct tree *tree, int stage, struct pathspec *match)
 142 {
 143         read_tree_fn_t fn = NULL;
 144         int i, err;
 145
 146         /*
 147          * Currently the only existing callers of this function all
 148          * call it with stage=1 and after making sure there is nothing
 149          * at that stage; we could always use read_one_entry_quick().
 150          *
 151          * But when we decide to straighten out git-read-tree not to
 152          * use unpack_trees() in some cases, this will probably start
 153          * to matter.
 154          */
 155
 156         /*
 157          * See if we have cache entry at the stage.  If so,
 158          * do it the original slow way, otherwise, append and then
 159          * sort at the end.
 160          */
 161         for (i = 0; !fn && i < active_nr; i++) {
 162                 const struct cache_entry *ce = active_cache[i];
 163                 if (ce_stage(ce) == stage)
 164                         fn = read_one_entry;
 165         }
 166
 167         if (!fn)
 168                 fn = read_one_entry_quick;
 169         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
 170         if (fn == read_one_entry || err)
 171                 return err;
 172
 173         /*
 174          * Sort the cache entry -- we need to nuke the cache tree, though.
 175          */
 176         cache_tree_free(&active_cache_tree);
 177         qsort(active_cache, active_nr, sizeof(active_cache[0]),
 178               cmp_cache_name_compare);
 179         return 0;
 180 }
 181
 182 struct tree *lookup_tree(const unsigned char *sha1)
 183 {
 184         struct object *obj = lookup_object(sha1);
 185         if (!obj)
 186                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
 187         if (!obj->type)
 188                 obj->type = OBJ_TREE;
 189         if (obj->type != OBJ_TREE) {
 190                 error("Object %s is a %s, not a tree",
 191                       sha1_to_hex(sha1), typename(obj->type));
 192                 return NULL;
 193         }
 194         return (struct tree *) obj;
 195 }
 196
 197 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 198 {
 199         if (item->object.parsed)
 200                 return 0;
 201         item->object.parsed = 1;
 202         item->buffer = buffer;
 203         item->size = size;
 204
 205         return 0;
 206 }
 207
 208 int parse_tree(struct tree *item)
 209 {
 210          enum object_type type;
 211          void *buffer;
 212          unsigned long size;
 213
 214         if (item->object.parsed)
 215                 return 0;
 216         buffer = read_sha1_file(item->object.sha1, &type, &size);
 217         if (!buffer)
 218                 return error("Could not read %s",
 219                              sha1_to_hex(item->object.sha1));
 220         if (type != OBJ_TREE) {
 221                 free(buffer);
 222                 return error("Object %s not a tree",
 223                              sha1_to_hex(item->object.sha1));
 224         }
 225         return parse_tree_buffer(item, buffer, size);
 226 }
 227
 228 struct tree *parse_tree_indirect(const unsigned char *sha1)
 229 {
 230         struct object *obj = parse_object(sha1);
 231         do {
 232                 if (!obj)
 233                         return NULL;
 234                 if (obj->type == OBJ_TREE)
 235                         return (struct tree *) obj;
 236                 else if (obj->type == OBJ_COMMIT)
 237                         obj = &(((struct commit *) obj)->tree->object);
 238                 else if (obj->type == OBJ_TAG)
 239                         obj = ((struct tag *) obj)->tagged;
 240                 else
 241                         return NULL;
 242                 if (!obj->parsed)
 243                         parse_object(obj->sha1);
 244         } while (1);
 245 }