print errno when reporting a system call error
[gitweb.git] / unpack-trees.c
index 3a8ee19fe837aae6939c3a6b902f6b067dcde9e4..aa15111fefc8ca333edeeeb3ac77a8b946e4c6a5 100644 (file)
@@ -10,6 +10,8 @@
 #include "attr.h"
 #include "split-index.h"
 #include "dir.h"
+#include "submodule.h"
+#include "submodule-config.h"
 
 /*
  * Error messages expected by scripts out of plumbing commands such as
@@ -45,6 +47,9 @@ static const char *unpack_plumbing_errors[NB_UNPACK_TREES_ERROR_TYPES] = {
 
        /* ERROR_WOULD_LOSE_ORPHANED_REMOVED */
        "Working tree file '%s' would be removed by sparse checkout update.",
+
+       /* ERROR_WOULD_LOSE_SUBMODULE */
+       "Submodule '%s' cannot checkout new HEAD.",
 };
 
 #define ERRORMSG(o,type) \
@@ -161,6 +166,8 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
                _("The following working tree files would be overwritten by sparse checkout update:\n%s");
        msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
                _("The following working tree files would be removed by sparse checkout update:\n%s");
+       msgs[ERROR_WOULD_LOSE_SUBMODULE] =
+               _("Cannot update submodule:\n%s");
 
        opts->show_all_errors = 1;
        /* rejected paths may not have a static buffer */
@@ -240,12 +247,75 @@ static void display_error_msgs(struct unpack_trees_options *o)
                fprintf(stderr, _("Aborting\n"));
 }
 
+static int check_submodule_move_head(const struct cache_entry *ce,
+                                    const char *old_id,
+                                    const char *new_id,
+                                    struct unpack_trees_options *o)
+{
+       const struct submodule *sub = submodule_from_ce(ce);
+       if (!sub)
+               return 0;
+
+       switch (sub->update_strategy.type) {
+       case SM_UPDATE_UNSPECIFIED:
+       case SM_UPDATE_CHECKOUT:
+               if (submodule_move_head(ce->name, old_id, new_id, SUBMODULE_MOVE_HEAD_DRY_RUN))
+                       return o->gently ? -1 :
+                               add_rejected_path(o, ERROR_WOULD_LOSE_SUBMODULE, ce->name);
+               return 0;
+       case SM_UPDATE_NONE:
+               return 0;
+       case SM_UPDATE_REBASE:
+       case SM_UPDATE_MERGE:
+       case SM_UPDATE_COMMAND:
+       default:
+               warning(_("submodule update strategy not supported for submodule '%s'"), ce->name);
+               return -1;
+       }
+}
+
+static void reload_gitmodules_file(struct index_state *index,
+                                  struct checkout *state)
+{
+       int i;
+       for (i = 0; i < index->cache_nr; i++) {
+               struct cache_entry *ce = index->cache[i];
+               if (ce->ce_flags & CE_UPDATE) {
+                       int r = strcmp(ce->name, ".gitmodules");
+                       if (r < 0)
+                               continue;
+                       else if (r == 0) {
+                               submodule_free();
+                               checkout_entry(ce, state, NULL);
+                               gitmodules_config();
+                               git_config(submodule_config, NULL);
+                       } else
+                               break;
+               }
+       }
+}
+
 /*
  * Unlink the last component and schedule the leading directories for
  * removal, such that empty directories get removed.
  */
 static void unlink_entry(const struct cache_entry *ce)
 {
+       const struct submodule *sub = submodule_from_ce(ce);
+       if (sub) {
+               switch (sub->update_strategy.type) {
+               case SM_UPDATE_UNSPECIFIED:
+               case SM_UPDATE_CHECKOUT:
+               case SM_UPDATE_REBASE:
+               case SM_UPDATE_MERGE:
+                       submodule_move_head(ce->name, "HEAD", NULL,
+                                           SUBMODULE_MOVE_HEAD_FORCE);
+                       break;
+               case SM_UPDATE_NONE:
+               case SM_UPDATE_COMMAND:
+                       return; /* Do not touch the submodule. */
+               }
+       }
        if (!check_leading_path(ce->name, ce_namelen(ce)))
                return;
        if (remove_or_warn(ce->ce_mode, ce->name))
@@ -301,6 +371,9 @@ static int check_updates(struct unpack_trees_options *o)
        remove_marked_cache_entries(index);
        remove_scheduled_dirs();
 
+       if (should_update_submodules() && o->update && !o->dry_run)
+               reload_gitmodules_file(index, &state);
+
        for (i = 0; i < index->cache_nr; i++) {
                struct cache_entry *ce = index->cache[i];
 
@@ -531,12 +604,18 @@ static int switch_cache_bottom(struct traverse_info *info)
        return ret;
 }
 
+static inline int are_same_oid(struct name_entry *name_j, struct name_entry *name_k)
+{
+       return name_j->oid && name_k->oid && !oidcmp(name_j->oid, name_k->oid);
+}
+
 static int traverse_trees_recursive(int n, unsigned long dirmask,
                                    unsigned long df_conflicts,
                                    struct name_entry *names,
                                    struct traverse_info *info)
 {
        int i, ret, bottom;
+       int nr_buf = 0;
        struct tree_desc t[MAX_UNPACK_TREES];
        void *buf[MAX_UNPACK_TREES];
        struct traverse_info newinfo;
@@ -553,18 +632,40 @@ static int traverse_trees_recursive(int n, unsigned long dirmask,
        newinfo.pathlen += tree_entry_len(p) + 1;
        newinfo.df_conflicts |= df_conflicts;
 
+       /*
+        * Fetch the tree from the ODB for each peer directory in the
+        * n commits.
+        *
+        * For 2- and 3-way traversals, we try to avoid hitting the
+        * ODB twice for the same OID.  This should yield a nice speed
+        * up in checkouts and merges when the commits are similar.
+        *
+        * We don't bother doing the full O(n^2) search for larger n,
+        * because wider traversals don't happen that often and we
+        * avoid the search setup.
+        *
+        * When 2 peer OIDs are the same, we just copy the tree
+        * descriptor data.  This implicitly borrows the buffer
+        * data from the earlier cell.
+        */
        for (i = 0; i < n; i++, dirmask >>= 1) {
-               const unsigned char *sha1 = NULL;
-               if (dirmask & 1)
-                       sha1 = names[i].oid->hash;
-               buf[i] = fill_tree_descriptor(t+i, sha1);
+               if (i > 0 && are_same_oid(&names[i], &names[i - 1]))
+                       t[i] = t[i - 1];
+               else if (i > 1 && are_same_oid(&names[i], &names[i - 2]))
+                       t[i] = t[i - 2];
+               else {
+                       const unsigned char *sha1 = NULL;
+                       if (dirmask & 1)
+                               sha1 = names[i].oid->hash;
+                       buf[nr_buf++] = fill_tree_descriptor(t+i, sha1);
+               }
        }
 
        bottom = switch_cache_bottom(&newinfo);
        ret = traverse_trees(n, t, &newinfo);
        restore_cache_bottom(&newinfo, bottom);
 
-       for (i = 0; i < n; i++)
+       for (i = 0; i < nr_buf; i++)
                free(buf[i]);
 
        return ret;
@@ -1358,17 +1459,26 @@ static int verify_uptodate_1(const struct cache_entry *ce,
        if (!lstat(ce->name, &st)) {
                int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
                unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
+
+               if (submodule_from_ce(ce)) {
+                       int r = check_submodule_move_head(ce,
+                               "HEAD", oid_to_hex(&ce->oid), o);
+                       if (r)
+                               return o->gently ? -1 :
+                                       add_rejected_path(o, error_type, ce->name);
+                       return 0;
+               }
+
                if (!changed)
                        return 0;
                /*
-                * NEEDSWORK: the current default policy is to allow
-                * submodule to be out of sync wrt the superproject
-                * index.  This needs to be tightened later for
-                * submodules that are marked to be automatically
-                * checked out.
+                * Historic default policy was to allow submodule to be out
+                * of sync wrt the superproject index. If the submodule was
+                * not considered interesting above, we don't care here.
                 */
                if (S_ISGITLINK(ce->ce_mode))
                        return 0;
+
                errno = 0;
        }
        if (errno == ENOENT)
@@ -1407,11 +1517,16 @@ static void invalidate_ce_path(const struct cache_entry *ce,
  * Currently, git does not checkout subprojects during a superproject
  * checkout, so it is not going to overwrite anything.
  */
-static int verify_clean_submodule(const struct cache_entry *ce,
+static int verify_clean_submodule(const char *old_sha1,
+                                 const struct cache_entry *ce,
                                  enum unpack_trees_error_types error_type,
                                  struct unpack_trees_options *o)
 {
-       return 0;
+       if (!submodule_from_ce(ce))
+               return 0;
+
+       return check_submodule_move_head(ce, old_sha1,
+                                        oid_to_hex(&ce->oid), o);
 }
 
 static int verify_clean_subdirectory(const struct cache_entry *ce,
@@ -1427,16 +1542,18 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
        struct dir_struct d;
        char *pathbuf;
        int cnt = 0;
-       unsigned char sha1[20];
 
-       if (S_ISGITLINK(ce->ce_mode) &&
-           resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
-               /* If we are not going to update the submodule, then
+       if (S_ISGITLINK(ce->ce_mode)) {
+               unsigned char sha1[20];
+               int sub_head = resolve_gitlink_ref(ce->name, "HEAD", sha1);
+               /*
+                * If we are not going to update the submodule, then
                 * we don't care.
                 */
-               if (!hashcmp(sha1, ce->oid.hash))
+               if (!sub_head && !hashcmp(sha1, ce->oid.hash))
                        return 0;
-               return verify_clean_submodule(ce, error_type, o);
+               return verify_clean_submodule(sub_head ? NULL : sha1_to_hex(sha1),
+                                             ce, error_type, o);
        }
 
        /*
@@ -1575,9 +1692,15 @@ static int verify_absent_1(const struct cache_entry *ce,
                path = xmemdupz(ce->name, len);
                if (lstat(path, &st))
                        ret = error_errno("cannot stat '%s'", path);
-               else
-                       ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
-                                                &st, error_type, o);
+               else {
+                       if (submodule_from_ce(ce))
+                               ret = check_submodule_move_head(ce,
+                                                               oid_to_hex(&ce->oid),
+                                                               NULL, o);
+                       else
+                               ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
+                                                        &st, error_type, o);
+               }
                free(path);
                return ret;
        } else if (lstat(ce->name, &st)) {
@@ -1585,6 +1708,10 @@ static int verify_absent_1(const struct cache_entry *ce,
                        return error_errno("cannot stat '%s'", ce->name);
                return 0;
        } else {
+               if (submodule_from_ce(ce))
+                       return check_submodule_move_head(ce, oid_to_hex(&ce->oid),
+                                                        NULL, o);
+
                return check_ok_to_remove(ce->name, ce_namelen(ce),
                                          ce_to_dtype(ce), ce, &st,
                                          error_type, o);
@@ -1640,6 +1767,15 @@ static int merged_entry(const struct cache_entry *ce,
                        return -1;
                }
                invalidate_ce_path(merge, o);
+
+               if (submodule_from_ce(ce)) {
+                       int ret = check_submodule_move_head(ce, NULL,
+                                                           oid_to_hex(&ce->oid),
+                                                           o);
+                       if (ret)
+                               return ret;
+               }
+
        } else if (!(old->ce_flags & CE_CONFLICTED)) {
                /*
                 * See if we can re-use the old CE directly?
@@ -1660,6 +1796,14 @@ static int merged_entry(const struct cache_entry *ce,
                        update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
                        invalidate_ce_path(old, o);
                }
+
+               if (submodule_from_ce(ce)) {
+                       int ret = check_submodule_move_head(ce, oid_to_hex(&old->oid),
+                                                           oid_to_hex(&ce->oid),
+                                                           o);
+                       if (ret)
+                               return ret;
+               }
        } else {
                /*
                 * Previously unmerged entry left as an existence