Fix crash when reading the empty tree
[git.git] / read-tree.c
index 52f06e3..49436bf 100644 (file)
@@ -9,6 +9,9 @@
 
 #include "object.h"
 #include "tree.h"
+#include "cache-tree.h"
+#include <sys/time.h>
+#include <signal.h>
 
 static int merge = 0;
 static int update = 0;
@@ -16,6 +19,8 @@ static int index_only = 0;
 static int nontrivial_merge = 0;
 static int trivial_merges_only = 0;
 static int aggressive = 0;
+static int verbose_update = 0;
+static volatile int progress_update = 0;
 
 static int head_idx = -1;
 static int merge_size = 0;
@@ -129,11 +134,9 @@ 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;
@@ -173,8 +176,7 @@ 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);
@@ -267,6 +269,28 @@ static void unlink_entry(char *name)
        }
 }
 
+static void progress_interval(int signum)
+{
+       progress_update = 1;
+}
+
+static void setup_progress_signal(void)
+{
+       struct sigaction sa;
+       struct itimerval v;
+
+       memset(&sa, 0, sizeof(sa));
+       sa.sa_handler = progress_interval;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       sigaction(SIGALRM, &sa, NULL);
+
+       v.it_interval.tv_sec = 1;
+       v.it_interval.tv_usec = 0;
+       v.it_value = v.it_interval;
+       setitimer(ITIMER_REAL, &v, NULL);
+}
+
 static void check_updates(struct cache_entry **src, int nr)
 {
        static struct checkout state = {
@@ -276,8 +300,43 @@ static void check_updates(struct cache_entry **src, int nr)
                .refresh_cache = 1,
        };
        unsigned short mask = htons(CE_UPDATE);
+       unsigned last_percent = 200, cnt = 0, total = 0;
+
+       if (update && verbose_update) {
+               for (total = cnt = 0; cnt < nr; cnt++) {
+                       struct cache_entry *ce = src[cnt];
+                       if (!ce->ce_mode || ce->ce_flags & mask)
+                               total++;
+               }
+
+               /* Don't bother doing this for very small updates */
+               if (total < 250)
+                       total = 0;
+
+               if (total) {
+                       fprintf(stderr, "Checking files out...\n");
+                       setup_progress_signal();
+                       progress_update = 1;
+               }
+               cnt = 0;
+       }
+
        while (nr--) {
                struct cache_entry *ce = *src++;
+
+               if (total) {
+                       if (!ce->ce_mode || ce->ce_flags & mask) {
+                               unsigned percent;
+                               cnt++;
+                               percent = (cnt * 100) / total;
+                               if (percent != last_percent ||
+                                   progress_update) {
+                                       fprintf(stderr, "%4u%% (%u/%u) done\r",
+                                               percent, cnt, total);
+                                       last_percent = percent;
+                               }
+                       }
+               }
                if (!ce->ce_mode) {
                        if (update)
                                unlink_entry(ce->name);
@@ -286,9 +345,13 @@ static void check_updates(struct cache_entry **src, int nr)
                if (ce->ce_flags & mask) {
                        ce->ce_flags &= ~mask;
                        if (update)
-                               checkout_entry(ce, &state);
+                               checkout_entry(ce, &state, NULL);
                }
        }
+       if (total) {
+               signal(SIGALRM, SIG_IGN);
+               fputc('\n', stderr);
+       }
 }
 
 static int unpack_trees(merge_fn_t fn)
@@ -359,6 +422,12 @@ 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);
@@ -374,8 +443,11 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
                        *merge = *old;
                } else {
                        verify_uptodate(old);
+                       invalidate_ce_path(old);
                }
        }
+       else
+               invalidate_ce_path(merge);
        merge->ce_flags &= ~htons(CE_STAGEMASK);
        add_cache_entry(merge, ADD_CACHE_OK_TO_ADD);
        return 1;
@@ -387,6 +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;
 }
 
@@ -505,9 +578,11 @@ static int threeway_merge(struct cache_entry **stages)
                 */
                if ((head_deleted && remote_deleted) ||
                    (head_deleted && remote && remote_match) ||
-                   (remote_deleted && head && head_match))
+                   (remote_deleted && head && head_match)) {
+                       if (index)
+                               return deleted_entry(index, index);
                        return 0;
-
+               }
                /*
                 * Added in both, identically.
                 */
@@ -564,7 +639,7 @@ static int twoway_merge(struct cache_entry **src)
        struct cache_entry *oldtree = src[1], *newtree = src[2];
 
        if (merge_size != 2)
-               return error("Cannot do a twoway merge of %d trees\n",
+               return error("Cannot do a twoway merge of %d trees",
                             merge_size);
 
        if (current) {
@@ -616,11 +691,13 @@ static int oneway_merge(struct cache_entry **src)
        struct cache_entry *a = src[1];
 
        if (merge_size != 1)
-               return error("Cannot do a oneway merge of %d trees\n",
+               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);
        }
@@ -639,6 +716,7 @@ 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)
@@ -649,7 +727,40 @@ static int read_cache_unmerged(void)
        return deleted;
 }
 
-static const char read_tree_usage[] = "git-read-tree (<sha> | -m [-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] [-u | -i] <sha1> [<sha2> [<sha3>]])";
 
 static struct cache_file cache_file;
 
@@ -660,6 +771,7 @@ int main(int argc, char **argv)
        merge_fn_t fn = NULL;
 
        setup_git_directory();
+       git_config(git_default_config);
 
        newfd = hold_index_file_for_update(&cache_file, get_index_file());
        if (newfd < 0)
@@ -680,6 +792,11 @@ int main(int argc, char **argv)
                        continue;
                }
 
+               if (!strcmp(arg, "-v")) {
+                       verbose_update = 1;
+                       continue;
+               }
+
                /* "-i" means "index only", meaning that a merge will
                 * not even look at the working tree.
                 */
@@ -744,10 +861,9 @@ int main(int argc, char **argv)
                        fn = twoway_merge;
                        break;
                case 3:
-                       fn = threeway_merge;
-                       break;
                default:
                        fn = threeway_merge;
+                       cache_tree_free(&active_cache_tree);
                        break;
                }
 
@@ -758,6 +874,18 @@ 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 && 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");