convert: drop arguments other than 'path' from would_convert_to_git()
[gitweb.git] / split-index.c
index 57088071fce3503fdb983f3543c07b0b29e6000a..21485e20665979458fb794ee4c3cc77c27032fa8 100644 (file)
@@ -16,13 +16,27 @@ int read_link_extension(struct index_state *istate,
 {
        const unsigned char *data = data_;
        struct split_index *si;
+       int ret;
+
        if (sz < 20)
                return error("corrupt link extension (too short)");
        si = init_split_index(istate);
        hashcpy(si->base_sha1, data);
        data += 20;
        sz -= 20;
-       if (sz)
+       if (!sz)
+               return 0;
+       si->delete_bitmap = ewah_new();
+       ret = ewah_read_mmap(si->delete_bitmap, data, sz);
+       if (ret < 0)
+               return error("corrupt delete bitmap in link extension");
+       data += ret;
+       sz -= ret;
+       si->replace_bitmap = ewah_new();
+       ret = ewah_read_mmap(si->replace_bitmap, data, sz);
+       if (ret < 0)
+               return error("corrupt replace bitmap in link extension");
+       if (ret != sz)
                return error("garbage at the end of link extension");
        return 0;
 }
@@ -60,15 +74,113 @@ static void mark_base_index_entries(struct index_state *base)
                base->cache[i]->index = i + 1;
 }
 
+void move_cache_to_base_index(struct index_state *istate)
+{
+       struct split_index *si = istate->split_index;
+       int i;
+
+       /*
+        * do not delete old si->base, its index entries may be shared
+        * with istate->cache[]. Accept a bit of leaking here because
+        * this code is only used by short-lived update-index.
+        */
+       si->base = xcalloc(1, sizeof(*si->base));
+       si->base->version = istate->version;
+       /* zero timestamp disables racy test in ce_write_index() */
+       si->base->timestamp = istate->timestamp;
+       ALLOC_GROW(si->base->cache, istate->cache_nr, si->base->cache_alloc);
+       si->base->cache_nr = istate->cache_nr;
+       memcpy(si->base->cache, istate->cache,
+              sizeof(*istate->cache) * istate->cache_nr);
+       mark_base_index_entries(si->base);
+       for (i = 0; i < si->base->cache_nr; i++)
+               si->base->cache[i]->ce_flags &= ~CE_UPDATE_IN_BASE;
+}
+
+static void mark_entry_for_delete(size_t pos, void *data)
+{
+       struct index_state *istate = data;
+       if (pos >= istate->cache_nr)
+               die("position for delete %d exceeds base index size %d",
+                   (int)pos, istate->cache_nr);
+       istate->cache[pos]->ce_flags |= CE_REMOVE;
+       istate->split_index->nr_deletions = 1;
+}
+
+static void replace_entry(size_t pos, void *data)
+{
+       struct index_state *istate = data;
+       struct split_index *si = istate->split_index;
+       struct cache_entry *dst, *src;
+
+       if (pos >= istate->cache_nr)
+               die("position for replacement %d exceeds base index size %d",
+                   (int)pos, istate->cache_nr);
+       if (si->nr_replacements >= si->saved_cache_nr)
+               die("too many replacements (%d vs %d)",
+                   si->nr_replacements, si->saved_cache_nr);
+       dst = istate->cache[pos];
+       if (dst->ce_flags & CE_REMOVE)
+               die("entry %d is marked as both replaced and deleted",
+                   (int)pos);
+       src = si->saved_cache[si->nr_replacements];
+       if (ce_namelen(src))
+               die("corrupt link extension, entry %d should have "
+                   "zero length name", (int)pos);
+       src->index = pos + 1;
+       src->ce_flags |= CE_UPDATE_IN_BASE;
+       src->ce_namelen = dst->ce_namelen;
+       copy_cache_entry(dst, src);
+       free(src);
+       si->nr_replacements++;
+}
+
 void merge_base_index(struct index_state *istate)
 {
        struct split_index *si = istate->split_index;
+       unsigned int i;
 
        mark_base_index_entries(si->base);
-       istate->cache_nr = si->base->cache_nr;
+
+       si->saved_cache     = istate->cache;
+       si->saved_cache_nr  = istate->cache_nr;
+       istate->cache_nr    = si->base->cache_nr;
+       istate->cache       = NULL;
+       istate->cache_alloc = 0;
        ALLOC_GROW(istate->cache, istate->cache_nr, istate->cache_alloc);
        memcpy(istate->cache, si->base->cache,
               sizeof(*istate->cache) * istate->cache_nr);
+
+       si->nr_deletions = 0;
+       si->nr_replacements = 0;
+       ewah_each_bit(si->replace_bitmap, replace_entry, istate);
+       ewah_each_bit(si->delete_bitmap, mark_entry_for_delete, istate);
+       if (si->nr_deletions)
+               remove_marked_cache_entries(istate);
+
+       for (i = si->nr_replacements; i < si->saved_cache_nr; i++) {
+               if (!ce_namelen(si->saved_cache[i]))
+                       die("corrupt link extension, entry %d should "
+                           "have non-zero length name", i);
+               add_index_entry(istate, si->saved_cache[i],
+                               ADD_CACHE_OK_TO_ADD |
+                               ADD_CACHE_KEEP_CACHE_TREE |
+                               /*
+                                * we may have to replay what
+                                * merge-recursive.c:update_stages()
+                                * does, which has this flag on
+                                */
+                               ADD_CACHE_SKIP_DFCHECK);
+               si->saved_cache[i] = NULL;
+       }
+
+       ewah_free(si->delete_bitmap);
+       ewah_free(si->replace_bitmap);
+       free(si->saved_cache);
+       si->delete_bitmap  = NULL;
+       si->replace_bitmap = NULL;
+       si->saved_cache    = NULL;
+       si->saved_cache_nr = 0;
 }
 
 void prepare_to_write_split_index(struct index_state *istate)
@@ -132,6 +244,7 @@ void prepare_to_write_split_index(struct index_state *istate)
                                ewah_set(si->delete_bitmap, i);
                        else if (ce->ce_flags & CE_UPDATE_IN_BASE) {
                                ewah_set(si->replace_bitmap, i);
+                               ce->ce_flags |= CE_STRIP_NAME;
                                ALLOC_GROW(entries, nr_entries+1, nr_alloc);
                                entries[nr_entries++] = ce;
                        }
@@ -141,6 +254,7 @@ void prepare_to_write_split_index(struct index_state *istate)
        for (i = 0; i < istate->cache_nr; i++) {
                ce = istate->cache[i];
                if ((!si->base || !ce->index) && !(ce->ce_flags & CE_REMOVE)) {
+                       assert(!(ce->ce_flags & CE_STRIP_NAME));
                        ALLOC_GROW(entries, nr_entries+1, nr_alloc);
                        entries[nr_entries++] = ce;
                }