#include "cache.h"
#include "split-index.h"
+#include "ewah/ewok.h"
struct split_index *init_split_index(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;
}
+static int write_strbuf(void *user_data, const void *data, size_t len)
+{
+ struct strbuf *sb = user_data;
+ strbuf_add(sb, data, len);
+ return len;
+}
+
int write_link_extension(struct strbuf *sb,
struct index_state *istate)
{
struct split_index *si = istate->split_index;
strbuf_add(sb, si->base_sha1, 20);
+ if (!si->delete_bitmap && !si->replace_bitmap)
+ return 0;
+ ewah_serialize_to(si->delete_bitmap, write_strbuf, sb);
+ ewah_serialize_to(si->replace_bitmap, write_strbuf, sb);
return 0;
}
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)
{
struct split_index *si = init_split_index(istate);
- /* take cache[] out temporarily */
+ struct cache_entry **entries = NULL, *ce;
+ int i, nr_entries = 0, nr_alloc = 0;
+
+ si->delete_bitmap = ewah_new();
+ si->replace_bitmap = ewah_new();
+
+ if (si->base) {
+ /* Go through istate->cache[] and mark CE_MATCHED to
+ * entry with positive index. We'll go through
+ * base->cache[] later to delete all entries in base
+ * that are not marked eith either CE_MATCHED or
+ * CE_UPDATE_IN_BASE. If istate->cache[i] is a
+ * duplicate, deduplicate it.
+ */
+ for (i = 0; i < istate->cache_nr; i++) {
+ struct cache_entry *base;
+ /* namelen is checked separately */
+ const unsigned int ondisk_flags =
+ CE_STAGEMASK | CE_VALID | CE_EXTENDED_FLAGS;
+ unsigned int ce_flags, base_flags, ret;
+ ce = istate->cache[i];
+ if (!ce->index)
+ continue;
+ if (ce->index > si->base->cache_nr) {
+ ce->index = 0;
+ continue;
+ }
+ ce->ce_flags |= CE_MATCHED; /* or "shared" */
+ base = si->base->cache[ce->index - 1];
+ if (ce == base)
+ continue;
+ if (ce->ce_namelen != base->ce_namelen ||
+ strcmp(ce->name, base->name)) {
+ ce->index = 0;
+ continue;
+ }
+ ce_flags = ce->ce_flags;
+ base_flags = base->ce_flags;
+ /* only on-disk flags matter */
+ ce->ce_flags &= ondisk_flags;
+ base->ce_flags &= ondisk_flags;
+ ret = memcmp(&ce->ce_stat_data, &base->ce_stat_data,
+ offsetof(struct cache_entry, name) -
+ offsetof(struct cache_entry, ce_stat_data));
+ ce->ce_flags = ce_flags;
+ base->ce_flags = base_flags;
+ if (ret)
+ ce->ce_flags |= CE_UPDATE_IN_BASE;
+ free(base);
+ si->base->cache[ce->index - 1] = ce;
+ }
+ for (i = 0; i < si->base->cache_nr; i++) {
+ ce = si->base->cache[i];
+ if ((ce->ce_flags & CE_REMOVE) ||
+ !(ce->ce_flags & CE_MATCHED))
+ 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;
+ }
+ }
+ }
+
+ 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;
+ }
+ ce->ce_flags &= ~CE_MATCHED;
+ }
+
+ /*
+ * take cache[] out temporarily, put entries[] in its place
+ * for writing
+ */
+ si->saved_cache = istate->cache;
si->saved_cache_nr = istate->cache_nr;
- istate->cache_nr = 0;
+ istate->cache = entries;
+ istate->cache_nr = nr_entries;
}
void finish_writing_split_index(struct index_state *istate)
{
struct split_index *si = init_split_index(istate);
+
+ ewah_free(si->delete_bitmap);
+ ewah_free(si->replace_bitmap);
+ si->delete_bitmap = NULL;
+ si->replace_bitmap = NULL;
+ free(istate->cache);
+ istate->cache = si->saved_cache;
istate->cache_nr = si->saved_cache_nr;
}
else
free(ce);
}
+
+void replace_index_entry_in_base(struct index_state *istate,
+ struct cache_entry *old,
+ struct cache_entry *new)
+{
+ if (old->index &&
+ istate->split_index &&
+ istate->split_index->base &&
+ old->index <= istate->split_index->base->cache_nr) {
+ new->index = old->index;
+ if (old != istate->split_index->base->cache[new->index - 1])
+ free(istate->split_index->base->cache[new->index - 1]);
+ istate->split_index->base->cache[new->index - 1] = new;
+ }
+}