Merge branch 'jc/cache-tree'

* jc/cache-tree: (26 commits)
  builtin-rm: squelch compiler warnings.
  git-write-tree writes garbage on sparc64
  Fix crash when reading the empty tree
  fsck-objects: do not segfault on missing tree in cache-tree
  cache-tree: a bit more debugging support.
  read-tree: invalidate cache-tree entry when a new index entry is added.
  Fix test-dump-cache-tree in one-tree disappeared case.
  fsck-objects: mark objects reachable from cache-tree
  cache-tree: replace a sscanf() by two strtol() calls
  cache-tree.c: typefix
  test-dump-cache-tree: validate the cached data as well.
  cache_tree_update: give an option to update cache-tree only.
  read-tree: teach 1-way merege and plain read to prime cache-tree.
  read-tree: teach 1 and 2 way merges about cache-tree.
  update-index: when --unresolve, smudge the relevant cache-tree entries.
  test-dump-cache-tree: report number of subtrees.
  cache-tree: sort the subtree entries.
  Teach fsck-objects about cache-tree.
  index: make the index file format extensible.
  cache-tree: protect against "git prune".
  ...

Conflicts:

	Makefile, builtin.h, git.c: resolved the same way as in next.

.gitignore

@@ -125,6 +125,7 @@ git-write-tree
 git-core-*/?*
 test-date
 test-delta
+test-dump-cache-tree
 common-cmds.h
 *.tar.gz
 *.dsc

Makefile

@@ -210,7 +210,7 @@ DIFF_OBJS = \
 	diffcore-delta.o log-tree.o
 
 LIB_OBJS = \
-	blob.o commit.o connect.o csum-file.o base85.o \
+	blob.o commit.o connect.o csum-file.o cache-tree.o base85.o \
 	date.o diff-delta.o entry.o exec_cmd.o ident.o index.o \
 	object.o pack-check.o patch-delta.o path.o pkt-line.o \
 	quote.o read-cache.o refs.o run-command.o dir.o \
@@ -626,6 +626,9 @@ test-date$X: test-date.c date.o ctype.o
 test-delta$X: test-delta.c diff-delta.o patch-delta.o
 	$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $^
 
+test-dump-cache-tree$X: dump-cache-tree.o $(GITLIBS)
+	$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
+
 check:
 	for i in *.c; do sparse $(ALL_CFLAGS) $(SPARSE_FLAGS) $$i || exit; done
 

builtin-add.c

@@ -8,6 +8,7 @@
 #include "cache.h"
 #include "builtin.h"
 #include "dir.h"
+#include "cache-tree.h"
 
 static const char builtin_add_usage[] =
 "git-add [-n] [-v] <filepattern>...";
@@ -117,6 +118,7 @@ static int add_file_to_index(const char *path, int verbose)
 		die("unable to add %s to index",path);
 	if (verbose)
 		printf("add '%s'\n", path);
+	cache_tree_invalidate_path(active_cache_tree, path);
 	return 0;
 }
 

builtin-apply.c

@@ -8,6 +8,7 @@
  */
 #include <fnmatch.h>
 #include "cache.h"
+#include "cache-tree.h"
 #include "quote.h"
 #include "blob.h"
 #include "delta.h"
@@ -1918,6 +1919,7 @@ static void remove_file(struct patch *patch)
 	if (write_index) {
 		if (remove_file_from_cache(patch->old_name) < 0)
 			die("unable to remove %s from index", patch->old_name);
+		cache_tree_invalidate_path(active_cache_tree, patch->old_name);
 	}
 	if (!cached)
 		unlink(patch->old_name);
@@ -2019,8 +2021,9 @@ static void create_file(struct patch *patch)
 
 	if (!mode)
 		mode = S_IFREG | 0644;
-	create_one_file(path, mode, buf, size);	
+	create_one_file(path, mode, buf, size);
 	add_index_file(path, mode, buf, size);
+	cache_tree_invalidate_path(active_cache_tree, path);
 }
 
 static void write_out_one_result(struct patch *patch)

builtin-read-tree.c

@@ -9,6 +9,7 @@
 
 #include "object.h"
 #include "tree.h"
+#include "cache-tree.h"
 #include <sys/time.h>
 #include <signal.h>
 #include "builtin.h"
@@ -427,6 +428,12 @@ 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);
+}
+
 /*
  * We do not want to remove or overwrite a working tree file that
  * is not tracked.
@@ -457,10 +464,13 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
 			*merge = *old;
 		} else {
 			verify_uptodate(old);
+			invalidate_ce_path(old);
 		}
 	}
-	else
+	else {
 		verify_absent(merge->name, "overwritten");
+		invalidate_ce_path(merge);
+	}
 
 	merge->ce_flags &= ~htons(CE_STAGEMASK);
 	add_cache_entry(merge, ADD_CACHE_OK_TO_ADD);
@@ -475,6 +485,7 @@ static int deleted_entry(struct cache_entry *ce, struct cache_entry *old)
 		verify_absent(ce->name, "removed");
 	ce->ce_mode = 0;
 	add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
+	invalidate_ce_path(ce);
 	return 1;
 }
 
@@ -750,6 +761,7 @@ 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)
@@ -760,6 +772,39 @@ static int read_cache_unmerged(void)
 	return deleted;
 }
 
+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] [-u | -i] <sha1> [<sha2> [<sha3>]])";
 
 static struct cache_file cache_file;
@@ -861,10 +906,9 @@ int cmd_read_tree(int argc, const char **argv, char **envp)
 			fn = twoway_merge;
 			break;
 		case 3:
-			fn = threeway_merge;
-			break;
 		default:
 			fn = threeway_merge;
+			cache_tree_free(&active_cache_tree);
 			break;
 		}
 
@@ -875,6 +919,18 @@ int cmd_read_tree(int argc, const char **argv, char **envp)
 	}
 
 	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 && trees->item && (!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");

builtin-rm.c

@@ -6,6 +6,7 @@
 #include "cache.h"
 #include "builtin.h"
 #include "dir.h"
+#include "cache-tree.h"
 
 static const char builtin_rm_usage[] =
 "git-rm [-n] [-v] [-f] <filepattern>...";
@@ -117,6 +118,7 @@ int cmd_rm(int argc, const char **argv, char **envp)
 
 		if (remove_file_from_cache(path))
 			die("git rm: unable to remove %s", path);
+		cache_tree_invalidate_path(active_cache_tree, path);
 	}
 
 	/*