read-tree -m -u: do not overwrite or remove untracked working tree files.

[git.git] / read-tree.c

diff --git a/read-tree.c b/read-tree.c
index 32fb6fa..82e2a9a 100644 (file)
--- a/read-tree.c
+++ b/read-tree.c
@@ -12,6 +12,7 @@
 #include <sys/time.h>
 #include <signal.h>
 
+static int reset = 0;
 static int merge = 0;
 static int update = 0;
 static int index_only = 0;
@@ -133,11 +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;
@@ -177,8 +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);
@@ -347,7 +345,7 @@ 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) {
@@ -410,20 +408,39 @@ static void verify_uptodate(struct cache_entry *ce)
 {
        struct stat st;
 
-       if (index_only)
+       if (index_only || reset)
                return;
 
        if (!lstat(ce->name, &st)) {
-               unsigned changed = ce_match_stat(ce, &st);
+               unsigned changed = ce_match_stat(ce, &st, 1);
                if (!changed)
                        return;
                errno = 0;
        }
+       if (reset) {
+               ce->ce_flags |= htons(CE_UPDATE);
+               return;
+       }
        if (errno == ENOENT)
                return;
        die("Entry '%s' not uptodate. Cannot merge.", ce->name);
 }
 
+/*
+ * We do not want to remove or overwrite a working tree file that
+ * is not tracked.
+ */
+static void verify_absent(const char *path, const char *action)
+{
+       struct stat st;
+
+       if (index_only || reset || !update)
+               return;
+       if (!lstat(path, &st))
+               die("Untracked working tree file '%s' "
+                   "would be %s by merge.", path, action);
+}
+
 static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
 {
        merge->ce_flags |= htons(CE_UPDATE);
@@ -441,6 +458,9 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
                        verify_uptodate(old);
                }
        }
+       else
+               verify_absent(merge->name, "overwritten");
+
        merge->ce_flags &= ~htons(CE_STAGEMASK);
        add_cache_entry(merge, ADD_CACHE_OK_TO_ADD);
        return 1;
@@ -450,6 +470,8 @@ static int deleted_entry(struct cache_entry *ce, struct cache_entry *old)
 {
        if (old)
                verify_uptodate(old);
+       else
+               verify_absent(ce->name, "removed");
        ce->ce_mode = 0;
        add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
        return 1;
@@ -485,6 +507,7 @@ static int threeway_merge(struct cache_entry **stages)
        int count;
        int head_match = 0;
        int remote_match = 0;
+       const char *path = NULL;
 
        int df_conflict_head = 0;
        int df_conflict_remote = 0;
@@ -496,8 +519,11 @@ static int threeway_merge(struct cache_entry **stages)
        for (i = 1; i < head_idx; i++) {
                if (!stages[i])
                        any_anc_missing = 1;
-               else
+               else {
+                       if (!path)
+                               path = stages[i]->name;
                        no_anc_exists = 0;
+               }
        }
 
        index = stages[0];
@@ -513,8 +539,15 @@ static int threeway_merge(struct cache_entry **stages)
                remote = NULL;
        }
 
+       if (!path && index)
+               path = index->name;
+       if (!path && head)
+               path = head->name;
+       if (!path && remote)
+               path = remote->name;
+
        /* First, if there's a #16 situation, note that to prevent #13
-        * and #14. 
+        * and #14.
         */
        if (!same(remote, head)) {
                for (i = 1; i < head_idx; i++) {
@@ -573,6 +606,8 @@ static int threeway_merge(struct cache_entry **stages)
                    (remote_deleted && head && head_match)) {
                        if (index)
                                return deleted_entry(index, index);
+                       else if (path)
+                               verify_absent(path, "removed");
                        return 0;
                }
                /*
@@ -590,6 +625,8 @@ static int threeway_merge(struct cache_entry **stages)
        if (index) {
                verify_uptodate(index);
        }
+       else if (path)
+               verify_absent(path, "overwritten");
 
        nontrivial_merge = 1;
 
@@ -687,11 +724,17 @@ static int oneway_merge(struct cache_entry **src)
                             merge_size);
 
        if (!a)
-               return 0;
+               return deleted_entry(old, old);
        if (old && same(old, a)) {
+               if (reset) {
+                       struct stat st;
+                       if (lstat(old->name, &st) ||
+                           ce_match_stat(old, &st, 1))
+                               old->ce_flags |= htons(CE_UPDATE);
+               }
                return keep_entry(old);
        }
-       return merged_entry(a, NULL);
+       return merged_entry(a, old);
 }
 
 static int read_cache_unmerged(void)
@@ -716,17 +759,18 @@ 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 const char read_tree_usage[] = "git-read-tree (<sha> | -m [--aggressive] [-u | -i] <sha1> [<sha2> [<sha3>]])";
 
 static struct cache_file cache_file;
 
 int main(int argc, char **argv)
 {
-       int i, newfd, reset, stage = 0;
+       int i, newfd, stage = 0;
        unsigned char sha1[20];
        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)
@@ -796,8 +840,8 @@ int main(int argc, char **argv)
                if (1 < index_only + update)
                        usage(read_tree_usage);
 
-               if (get_sha1(arg, sha1) < 0)
-                       usage(read_tree_usage);
+               if (get_sha1(arg, sha1))
+                       die("Not a valid object name %s", arg);
                if (list_tree(sha1) < 0)
                        die("failed to unpack tree object %s", arg);
                stage++;