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-rw-r--r--third_party/git/split-index.c473
1 files changed, 0 insertions, 473 deletions
diff --git a/third_party/git/split-index.c b/third_party/git/split-index.c
deleted file mode 100644
index e6154e4ea9..0000000000
--- a/third_party/git/split-index.c
+++ /dev/null
@@ -1,473 +0,0 @@
-#include "cache.h"
-#include "split-index.h"
-#include "ewah/ewok.h"
-
-struct split_index *init_split_index(struct index_state *istate)
-{
-	if (!istate->split_index) {
-		istate->split_index = xcalloc(1, sizeof(*istate->split_index));
-		istate->split_index->refcount = 1;
-	}
-	return istate->split_index;
-}
-
-int read_link_extension(struct index_state *istate,
-			 const void *data_, unsigned long sz)
-{
-	const unsigned char *data = data_;
-	struct split_index *si;
-	int ret;
-
-	if (sz < the_hash_algo->rawsz)
-		return error("corrupt link extension (too short)");
-	si = init_split_index(istate);
-	hashcpy(si->base_oid.hash, data);
-	data += the_hash_algo->rawsz;
-	sz -= the_hash_algo->rawsz;
-	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;
-}
-
-int write_link_extension(struct strbuf *sb,
-			 struct index_state *istate)
-{
-	struct split_index *si = istate->split_index;
-	strbuf_add(sb, si->base_oid.hash, the_hash_algo->rawsz);
-	if (!si->delete_bitmap && !si->replace_bitmap)
-		return 0;
-	ewah_serialize_strbuf(si->delete_bitmap, sb);
-	ewah_serialize_strbuf(si->replace_bitmap, sb);
-	return 0;
-}
-
-static void mark_base_index_entries(struct index_state *base)
-{
-	int i;
-	/*
-	 * To keep track of the shared entries between
-	 * istate->base->cache[] and istate->cache[], base entry
-	 * position is stored in each base entry. All positions start
-	 * from 1 instead of 0, which is reserved to say "this is a new
-	 * entry".
-	 */
-	for (i = 0; i < base->cache_nr; i++)
-		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;
-
-	/*
-	 * If there was a previous base index, then transfer ownership of allocated
-	 * entries to the parent index.
-	 */
-	if (si->base &&
-		si->base->ce_mem_pool) {
-
-		if (!istate->ce_mem_pool)
-			mem_pool_init(&istate->ce_mem_pool, 0);
-
-		mem_pool_combine(istate->ce_mem_pool, istate->split_index->base->ce_mem_pool);
-	}
-
-	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;
-
-	/*
-	 * The mem_pool needs to move with the allocated entries.
-	 */
-	si->base->ce_mem_pool = istate->ce_mem_pool;
-	istate->ce_mem_pool = NULL;
-
-	COPY_ARRAY(si->base->cache, 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++;
-}
-
-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);
-	discard_cache_entry(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);
-
-	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);
-	COPY_ARRAY(istate->cache, si->base->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, 0);
-
-	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_AND_NULL(si->saved_cache);
-	si->delete_bitmap  = NULL;
-	si->replace_bitmap = NULL;
-	si->saved_cache_nr = 0;
-}
-
-/*
- * Compare most of the fields in two cache entries, i.e. all except the
- * hashmap_entry and the name.
- */
-static int compare_ce_content(struct cache_entry *a, struct cache_entry *b)
-{
-	const unsigned int ondisk_flags = CE_STAGEMASK | CE_VALID |
-					  CE_EXTENDED_FLAGS;
-	unsigned int ce_flags = a->ce_flags;
-	unsigned int base_flags = b->ce_flags;
-	int ret;
-
-	/* only on-disk flags matter */
-	a->ce_flags &= ondisk_flags;
-	b->ce_flags &= ondisk_flags;
-	ret = memcmp(&a->ce_stat_data, &b->ce_stat_data,
-		     offsetof(struct cache_entry, name) -
-		     offsetof(struct cache_entry, ce_stat_data));
-	a->ce_flags = ce_flags;
-	b->ce_flags = base_flags;
-
-	return ret;
-}
-
-void prepare_to_write_split_index(struct index_state *istate)
-{
-	struct split_index *si = init_split_index(istate);
-	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 with 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;
-			ce = istate->cache[i];
-			if (!ce->index) {
-				/*
-				 * During simple update index operations this
-				 * is a cache entry that is not present in
-				 * the shared index.  It will be added to the
-				 * split index.
-				 *
-				 * However, it might also represent a file
-				 * that already has a cache entry in the
-				 * shared index, but a new index has just
-				 * been constructed by unpack_trees(), and
-				 * this entry now refers to different content
-				 * than what was recorded in the original
-				 * index, e.g. during 'read-tree -m HEAD^' or
-				 * 'checkout HEAD^'.  In this case the
-				 * original entry in the shared index will be
-				 * marked as deleted, and this entry will be
-				 * added to the split index.
-				 */
-				continue;
-			}
-			if (ce->index > si->base->cache_nr) {
-				BUG("ce refers to a shared ce at %d, which is beyond the shared index size %d",
-				    ce->index, si->base->cache_nr);
-			}
-			ce->ce_flags |= CE_MATCHED; /* or "shared" */
-			base = si->base->cache[ce->index - 1];
-			if (ce == base) {
-				/* The entry is present in the shared index. */
-				if (ce->ce_flags & CE_UPDATE_IN_BASE) {
-					/*
-					 * Already marked for inclusion in
-					 * the split index, either because
-					 * the corresponding file was
-					 * modified and the cached stat data
-					 * was refreshed, or because there
-					 * is already a replacement entry in
-					 * the split index.
-					 * Nothing more to do here.
-					 */
-				} else if (!ce_uptodate(ce) &&
-					   is_racy_timestamp(istate, ce)) {
-					/*
-					 * A racily clean cache entry stored
-					 * only in the shared index: it must
-					 * be added to the split index, so
-					 * the subsequent do_write_index()
-					 * can smudge its stat data.
-					 */
-					ce->ce_flags |= CE_UPDATE_IN_BASE;
-				} else {
-					/*
-					 * The entry is only present in the
-					 * shared index and it was not
-					 * refreshed.
-					 * Just leave it there.
-					 */
-				}
-				continue;
-			}
-			if (ce->ce_namelen != base->ce_namelen ||
-			    strcmp(ce->name, base->name)) {
-				ce->index = 0;
-				continue;
-			}
-			/*
-			 * This is the copy of a cache entry that is present
-			 * in the shared index, created by unpack_trees()
-			 * while it constructed a new index.
-			 */
-			if (ce->ce_flags & CE_UPDATE_IN_BASE) {
-				/*
-				 * Already marked for inclusion in the split
-				 * index, either because the corresponding
-				 * file was modified and the cached stat data
-				 * was refreshed, or because the original
-				 * entry already had a replacement entry in
-				 * the split index.
-				 * Nothing to do.
-				 */
-			} else if (!ce_uptodate(ce) &&
-				   is_racy_timestamp(istate, ce)) {
-				/*
-				 * A copy of a racily clean cache entry from
-				 * the shared index.  It must be added to
-				 * the split index, so the subsequent
-				 * do_write_index() can smudge its stat data.
-				 */
-				ce->ce_flags |= CE_UPDATE_IN_BASE;
-			} else {
-				/*
-				 * Thoroughly compare the cached data to see
-				 * whether it should be marked for inclusion
-				 * in the split index.
-				 *
-				 * This comparison might be unnecessary, as
-				 * code paths modifying the cached data do
-				 * set CE_UPDATE_IN_BASE as well.
-				 */
-				if (compare_ce_content(ce, base))
-					ce->ce_flags |= CE_UPDATE_IN_BASE;
-			}
-			discard_cache_entry(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;
-			}
-			if (is_null_oid(&ce->oid))
-				istate->drop_cache_tree = 1;
-		}
-	}
-
-	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 = 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;
-}
-
-void discard_split_index(struct index_state *istate)
-{
-	struct split_index *si = istate->split_index;
-	if (!si)
-		return;
-	istate->split_index = NULL;
-	si->refcount--;
-	if (si->refcount)
-		return;
-	if (si->base) {
-		discard_index(si->base);
-		free(si->base);
-	}
-	free(si);
-}
-
-void save_or_free_index_entry(struct index_state *istate, struct cache_entry *ce)
-{
-	if (ce->index &&
-	    istate->split_index &&
-	    istate->split_index->base &&
-	    ce->index <= istate->split_index->base->cache_nr &&
-	    ce == istate->split_index->base->cache[ce->index - 1])
-		ce->ce_flags |= CE_REMOVE;
-	else
-		discard_cache_entry(ce);
-}
-
-void replace_index_entry_in_base(struct index_state *istate,
-				 struct cache_entry *old_entry,
-				 struct cache_entry *new_entry)
-{
-	if (old_entry->index &&
-	    istate->split_index &&
-	    istate->split_index->base &&
-	    old_entry->index <= istate->split_index->base->cache_nr) {
-		new_entry->index = old_entry->index;
-		if (old_entry != istate->split_index->base->cache[new_entry->index - 1])
-			discard_cache_entry(istate->split_index->base->cache[new_entry->index - 1]);
-		istate->split_index->base->cache[new_entry->index - 1] = new_entry;
-	}
-}
-
-void add_split_index(struct index_state *istate)
-{
-	if (!istate->split_index) {
-		init_split_index(istate);
-		istate->cache_changed |= SPLIT_INDEX_ORDERED;
-	}
-}
-
-void remove_split_index(struct index_state *istate)
-{
-	if (istate->split_index) {
-		if (istate->split_index->base) {
-			/*
-			 * When removing the split index, we need to move
-			 * ownership of the mem_pool associated with the
-			 * base index to the main index. There may be cache entries
-			 * allocated from the base's memory pool that are shared with
-			 * the_index.cache[].
-			 */
-			mem_pool_combine(istate->ce_mem_pool,
-					 istate->split_index->base->ce_mem_pool);
-
-			/*
-			 * The split index no longer owns the mem_pool backing
-			 * its cache array. As we are discarding this index,
-			 * mark the index as having no cache entries, so it
-			 * will not attempt to clean up the cache entries or
-			 * validate them.
-			 */
-			istate->split_index->base->cache_nr = 0;
-		}
-
-		/*
-		 * We can discard the split index because its
-		 * memory pool has been incorporated into the
-		 * memory pool associated with the the_index.
-		 */
-		discard_split_index(istate);
-
-		istate->cache_changed |= SOMETHING_CHANGED;
-	}
-}