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, retval = 0, oldlen = base->len;
  56
  57         if (parse_tree(tree))
  58                 return -1;
  59
  60         init_tree_desc(&desc, tree->buffer, tree->size);
  61
  62         while (tree_entry(&desc, &entry)) {
  63                 if (retval != 2) {
  64                         retval = tree_entry_interesting(&entry, base, 0, pathspec);
  65                         if (retval < 0)
  66                                 break;
  67                         if (retval == 0)
  68                                 continue;
  69                 }
  70
  71                 switch (fn(entry.sha1, base->buf, base->len,
  72                            entry.path, entry.mode, stage, context)) {
  73                 case 0:
  74                         continue;
  75                 case READ_TREE_RECURSIVE:
  76                         break;
  77                 default:
  78                         return -1;
  79                 }
  80
  81                 if (S_ISDIR(entry.mode))
  82                         hashcpy(sha1, entry.sha1);
  83                 else if (S_ISGITLINK(entry.mode)) {
  84                         struct commit *commit;
  85
  86                         commit = lookup_commit(entry.sha1);
  87                         if (!commit)
  88                                 die("Commit %s in submodule path %s%s not found",
  89                                     sha1_to_hex(entry.sha1),
  90                                     base->buf, entry.path);
  91
  92                         if (parse_commit(commit))
  93                                 die("Invalid commit %s in submodule path %s%s",
  94                                     sha1_to_hex(entry.sha1),
  95                                     base->buf, entry.path);
  96
  97                         hashcpy(sha1, commit->tree->object.sha1);
  98                 }
  99                 else
 100                         continue;
 101
 102                 len = tree_entry_len(entry.path, entry.sha1);
 103                 strbuf_add(base, entry.path, len);
 104                 strbuf_addch(base, '/');
 105                 retval = read_tree_1(lookup_tree(sha1),
 106                                      base, stage, pathspec,
 107                                      fn, context);
 108                 strbuf_setlen(base, oldlen);
 109                 if (retval)
 110                         return -1;
 111         }
 112         return 0;
 113 }
 114
 115 int read_tree_recursive(struct tree *tree,
 116                         const char *base, int baselen,
 117                         int stage, struct pathspec *pathspec,
 118                         read_tree_fn_t fn, void *context)
 119 {
 120         struct strbuf sb = STRBUF_INIT;
 121         int ret;
 122
 123         strbuf_add(&sb, base, baselen);
 124         ret = read_tree_1(tree, &sb, stage, pathspec, fn, context);
 125         strbuf_release(&sb);
 126         return ret;
 127 }
 128
 129 static int cmp_cache_name_compare(const void *a_, const void *b_)
 130 {
 131         const struct cache_entry *ce1, *ce2;
 132
 133         ce1 = *((const struct cache_entry **)a_);
 134         ce2 = *((const struct cache_entry **)b_);
 135         return cache_name_compare(ce1->name, ce1->ce_flags,
 136                                   ce2->name, ce2->ce_flags);
 137 }
 138
 139 int read_tree(struct tree *tree, int stage, struct pathspec *match)
 140 {
 141         read_tree_fn_t fn = NULL;
 142         int i, err;
 143
 144         /*
 145          * Currently the only existing callers of this function all
 146          * call it with stage=1 and after making sure there is nothing
 147          * at that stage; we could always use read_one_entry_quick().
 148          *
 149          * But when we decide to straighten out git-read-tree not to
 150          * use unpack_trees() in some cases, this will probably start
 151          * to matter.
 152          */
 153
 154         /*
 155          * See if we have cache entry at the stage.  If so,
 156          * do it the original slow way, otherwise, append and then
 157          * sort at the end.
 158          */
 159         for (i = 0; !fn && i < active_nr; i++) {
 160                 struct cache_entry *ce = active_cache[i];
 161                 if (ce_stage(ce) == stage)
 162                         fn = read_one_entry;
 163         }
 164
 165         if (!fn)
 166                 fn = read_one_entry_quick;
 167         err = read_tree_recursive(tree, "", 0, stage, match, fn, NULL);
 168         if (fn == read_one_entry || err)
 169                 return err;
 170
 171         /*
 172          * Sort the cache entry -- we need to nuke the cache tree, though.
 173          */
 174         cache_tree_free(&active_cache_tree);
 175         qsort(active_cache, active_nr, sizeof(active_cache[0]),
 176               cmp_cache_name_compare);
 177         return 0;
 178 }
 179
 180 struct tree *lookup_tree(const unsigned char *sha1)
 181 {
 182         struct object *obj = lookup_object(sha1);
 183         if (!obj)
 184                 return create_object(sha1, OBJ_TREE, alloc_tree_node());
 185         if (!obj->type)
 186                 obj->type = OBJ_TREE;
 187         if (obj->type != OBJ_TREE) {
 188                 error("Object %s is a %s, not a tree",
 189                       sha1_to_hex(sha1), typename(obj->type));
 190                 return NULL;
 191         }
 192         return (struct tree *) obj;
 193 }
 194
 195 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 196 {
 197         if (item->object.parsed)
 198                 return 0;
 199         item->object.parsed = 1;
 200         item->buffer = buffer;
 201         item->size = size;
 202
 203         return 0;
 204 }
 205
 206 int parse_tree(struct tree *item)
 207 {
 208          enum object_type type;
 209          void *buffer;
 210          unsigned long size;
 211
 212         if (item->object.parsed)
 213                 return 0;
 214         buffer = read_sha1_file(item->object.sha1, &type, &size);
 215         if (!buffer)
 216                 return error("Could not read %s",
 217                              sha1_to_hex(item->object.sha1));
 218         if (type != OBJ_TREE) {
 219                 free(buffer);
 220                 return error("Object %s not a tree",
 221                              sha1_to_hex(item->object.sha1));
 222         }
 223         return parse_tree_buffer(item, buffer, size);
 224 }
 225
 226 struct tree *parse_tree_indirect(const unsigned char *sha1)
 227 {
 228         struct object *obj = parse_object(sha1);
 229         do {
 230                 if (!obj)
 231                         return NULL;
 232                 if (obj->type == OBJ_TREE)
 233                         return (struct tree *) obj;
 234                 else if (obj->type == OBJ_COMMIT)
 235                         obj = &(((struct commit *) obj)->tree->object);
 236                 else if (obj->type == OBJ_TAG)
 237                         obj = ((struct tag *) obj)->tagged;
 238                 else
 239                         return NULL;
 240                 if (!obj->parsed)
 241                         parse_object(obj->sha1);
 242         } while (1);
 243 }