read-tree: --prefix=<path>/ option.
[gitweb.git] / read-tree.c
index 4422dbf424a5f4fd491811648acd3273aba529f3..8b91affe899e065349979c8f4b347560ecd0063a 100644 (file)
@@ -9,6 +9,7 @@
 
 #include "object.h"
 #include "tree.h"
+#include "cache-tree.h"
 #include <sys/time.h>
 #include <signal.h>
 
@@ -20,6 +21,7 @@ static int trivial_merges_only = 0;
 static int aggressive = 0;
 static int verbose_update = 0;
 static volatile int progress_update = 0;
+static const char *prefix = NULL;
 
 static int head_idx = -1;
 static int merge_size = 0;
@@ -133,11 +135,9 @@ static int unpack_trees_rec(struct tree_entry_list **posns, int len,
                pathlen = strlen(first);
                ce_size = cache_entry_size(baselen + pathlen);
 
-               src = xmalloc(sizeof(struct cache_entry *) * src_size);
-               memset(src, 0, sizeof(struct cache_entry *) * src_size);
+               src = xcalloc(src_size, sizeof(struct cache_entry *));
 
-               subposns = xmalloc(sizeof(struct tree_list_entry *) * len);
-               memset(subposns, 0, sizeof(struct tree_list_entry *) * len);
+               subposns = xcalloc(len, sizeof(struct tree_list_entry *));
 
                if (cache_name && !strcmp(cache_name, first)) {
                        any_files = 1;
@@ -177,8 +177,7 @@ static int unpack_trees_rec(struct tree_entry_list **posns, int len,
                        else
                                ce_stage = 2;
 
-                       ce = xmalloc(ce_size);
-                       memset(ce, 0, ce_size);
+                       ce = xcalloc(1, ce_size);
                        ce->ce_mode = create_ce_mode(posns[i]->mode);
                        ce->ce_flags = create_ce_flags(baselen + pathlen,
                                                       ce_stage);
@@ -371,7 +370,8 @@ static int unpack_trees(merge_fn_t fn)
                        posns[i] = ((struct tree *) posn->item)->entries;
                        posn = posn->next;
                }
-               if (unpack_trees_rec(posns, len, "", fn, &indpos))
+               if (unpack_trees_rec(posns, len, prefix ? prefix : "",
+                                    fn, &indpos))
                        return -1;
        }
 
@@ -424,6 +424,12 @@ static void verify_uptodate(struct cache_entry *ce)
        die("Entry '%s' not uptodate. Cannot merge.", ce->name);
 }
 
+static void invalidate_ce_path(struct cache_entry *ce)
+{
+       if (ce)
+               cache_tree_invalidate_path(active_cache_tree, ce->name);
+}
+
 static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
 {
        merge->ce_flags |= htons(CE_UPDATE);
@@ -439,6 +445,7 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
                        *merge = *old;
                } else {
                        verify_uptodate(old);
+                       invalidate_ce_path(old);
                }
        }
        merge->ce_flags &= ~htons(CE_STAGEMASK);
@@ -452,6 +459,7 @@ static int deleted_entry(struct cache_entry *ce, struct cache_entry *old)
                verify_uptodate(old);
        ce->ce_mode = 0;
        add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
+       invalidate_ce_path(ce);
        return 1;
 }
 
@@ -671,6 +679,28 @@ static int twoway_merge(struct cache_entry **src)
                return deleted_entry(oldtree, current);
 }
 
+/*
+ * Bind merge.
+ *
+ * Keep the index entries at stage0, collapse stage1 but make sure
+ * stage0 does not have anything in prefix.
+ */
+static int bind_merge(struct cache_entry **src)
+{
+       struct cache_entry *old = src[0];
+       struct cache_entry *a = src[1];
+
+       if (merge_size != 1)
+               return error("Cannot do a bind merge of %d trees\n",
+                            merge_size);
+       if (!a)
+               return merged_entry(old, NULL);
+       if (old)
+               die("Entry '%s' overlaps.  Cannot bind.", a->name);
+
+       return merged_entry(a, NULL);
+}
+
 /*
  * One-way merge.
  *
@@ -686,8 +716,10 @@ static int oneway_merge(struct cache_entry **src)
                return error("Cannot do a oneway merge of %d trees",
                             merge_size);
 
-       if (!a)
+       if (!a) {
+               invalidate_ce_path(old);
                return 0;
+       }
        if (old && same(old, a)) {
                return keep_entry(old);
        }
@@ -706,6 +738,7 @@ static int read_cache_unmerged(void)
                struct cache_entry *ce = active_cache[i];
                if (ce_stage(ce)) {
                        deleted++;
+                       invalidate_ce_path(ce);
                        continue;
                }
                if (deleted)
@@ -716,7 +749,40 @@ static int read_cache_unmerged(void)
        return deleted;
 }
 
-static const char read_tree_usage[] = "git-read-tree (<sha> | -m [--aggressive] [-u | -i] <sha1> [<sha2> [<sha3>]])";
+static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
+{
+       struct tree_entry_list *ent;
+       int cnt;
+       
+       memcpy(it->sha1, tree->object.sha1, 20);
+       for (cnt = 0, ent = tree->entries; ent; ent = ent->next) {
+               if (!ent->directory)
+                       cnt++;
+               else {
+                       struct cache_tree_sub *sub;
+                       struct tree *subtree = (struct tree *)ent->item.tree;
+                       if (!subtree->object.parsed)
+                               parse_tree(subtree);
+                       sub = cache_tree_sub(it, ent->name);
+                       sub->cache_tree = cache_tree();
+                       prime_cache_tree_rec(sub->cache_tree, subtree);
+                       cnt += sub->cache_tree->entry_count;
+               }
+       }
+       it->entry_count = cnt;
+}
+
+static void prime_cache_tree(void)
+{
+       struct tree *tree = (struct tree *)trees->item;
+       if (!tree)
+               return;
+       active_cache_tree = cache_tree();
+       prime_cache_tree_rec(active_cache_tree, tree);
+
+}
+
+static const char read_tree_usage[] = "git-read-tree (<sha> | [[-m [--aggressive] | --reset | --prefix=<prefix>] [-u | -i]] <sha1> [<sha2> [<sha3>]])";
 
 static struct cache_file cache_file;
 
@@ -761,9 +827,24 @@ int main(int argc, char **argv)
                        continue;
                }
 
+               /* "--prefix=<subdirectory>/" means keep the current index
+                *  entries and put the entries from the tree under the
+                * given subdirectory.
+                */
+               if (!strncmp(arg, "--prefix=", 9)) {
+                       if (stage || merge || prefix)
+                               usage(read_tree_usage);
+                       prefix = arg + 9;
+                       merge = 1;
+                       stage = 1;
+                       if (read_cache_unmerged())
+                               die("you need to resolve your current index first");
+                       continue;
+               }
+
                /* This differs from "-m" in that we'll silently ignore unmerged entries */
                if (!strcmp(arg, "--reset")) {
-                       if (stage || merge)
+                       if (stage || merge || prefix)
                                usage(read_tree_usage);
                        reset = 1;
                        merge = 1;
@@ -784,7 +865,7 @@ int main(int argc, char **argv)
 
                /* "-m" stands for "merge", meaning we start in stage 1 */
                if (!strcmp(arg, "-m")) {
-                       if (stage || merge)
+                       if (stage || merge || prefix)
                                usage(read_tree_usage);
                        if (read_cache_unmerged())
                                die("you need to resolve your current index first");
@@ -806,21 +887,39 @@ int main(int argc, char **argv)
        if ((update||index_only) && !merge)
                usage(read_tree_usage);
 
+       if (prefix) {
+               int pfxlen = strlen(prefix);
+               int pos;
+               if (prefix[pfxlen-1] != '/')
+                       die("prefix must end with /");
+               if (stage != 2)
+                       die("binding merge takes only one tree");
+               pos = cache_name_pos(prefix, pfxlen);
+               if (0 <= pos)
+                       die("corrupt index file");
+               pos = -pos-1;
+               if (pos < active_nr &&
+                   !strncmp(active_cache[pos]->name, prefix, pfxlen))
+                       die("subdirectory '%s' already exists.", prefix);
+               pos = cache_name_pos(prefix, pfxlen-1);
+               if (0 <= pos)
+                       die("file '%.*s' already exists.", pfxlen-1, prefix);
+       }
+
        if (merge) {
                if (stage < 2)
                        die("just how do you expect me to merge %d trees?", stage-1);
                switch (stage - 1) {
                case 1:
-                       fn = oneway_merge;
+                       fn = prefix ? bind_merge : oneway_merge;
                        break;
                case 2:
                        fn = twoway_merge;
                        break;
                case 3:
-                       fn = threeway_merge;
-                       break;
                default:
                        fn = threeway_merge;
+                       cache_tree_free(&active_cache_tree);
                        break;
                }
 
@@ -831,6 +930,18 @@ int main(int argc, char **argv)
        }
 
        unpack_trees(fn);
+
+       /*
+        * When reading only one tree (either the most basic form,
+        * "-m ent" or "--reset ent" form), we can obtain a fully
+        * valid cache-tree because the index must match exactly
+        * what came from the tree.
+        */
+       if (trees->item && !prefix && (!merge || (stage == 2))) {
+               cache_tree_free(&active_cache_tree);
+               prime_cache_tree();
+       }
+
        if (write_cache(newfd, active_cache, active_nr) ||
            commit_index_file(&cache_file))
                die("unable to write new index file");