merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 398 insertions, 0 deletions

diff --git a/third_party/git/refs/debug.c b/third_party/git/refs/debug.c
new file mode 100644
index 000000000000..922e64fa6ad9
--- /dev/null
+++ b/third_party/git/refs/debug.c
@@ -0,0 +1,398 @@
+
+#include "refs-internal.h"
+#include "trace.h"
+
+static struct trace_key trace_refs = TRACE_KEY_INIT(REFS);
+
+struct debug_ref_store {
+	struct ref_store base;
+	struct ref_store *refs;
+};
+
+extern struct ref_storage_be refs_be_debug;
+
+struct ref_store *maybe_debug_wrap_ref_store(const char *gitdir, struct ref_store *store)
+{
+	struct debug_ref_store *res;
+	struct ref_storage_be *be_copy;
+
+	if (!trace_want(&trace_refs)) {
+		return store;
+	}
+	res = xmalloc(sizeof(struct debug_ref_store));
+	be_copy = xmalloc(sizeof(*be_copy));
+	*be_copy = refs_be_debug;
+	/* we never deallocate backends, so safe to copy the pointer. */
+	be_copy->name = store->be->name;
+	trace_printf_key(&trace_refs, "ref_store for %s\n", gitdir);
+	res->refs = store;
+	base_ref_store_init((struct ref_store *)res, be_copy);
+	return (struct ref_store *)res;
+}
+
+static int debug_init_db(struct ref_store *refs, struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
+	int res = drefs->refs->be->init_db(drefs->refs, err);
+	trace_printf_key(&trace_refs, "init_db: %d\n", res);
+	return res;
+}
+
+static int debug_transaction_prepare(struct ref_store *refs,
+				     struct ref_transaction *transaction,
+				     struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
+	int res;
+	transaction->ref_store = drefs->refs;
+	res = drefs->refs->be->transaction_prepare(drefs->refs, transaction,
+						   err);
+	trace_printf_key(&trace_refs, "transaction_prepare: %d\n", res);
+	return res;
+}
+
+static void print_update(int i, const char *refname,
+			 const struct object_id *old_oid,
+			 const struct object_id *new_oid, unsigned int flags,
+			 unsigned int type, const char *msg)
+{
+	char o[GIT_MAX_HEXSZ + 1] = "null";
+	char n[GIT_MAX_HEXSZ + 1] = "null";
+	if (old_oid)
+		oid_to_hex_r(o, old_oid);
+	if (new_oid)
+		oid_to_hex_r(n, new_oid);
+
+	type &= 0xf; /* see refs.h REF_* */
+	flags &= REF_HAVE_NEW | REF_HAVE_OLD | REF_NO_DEREF |
+		REF_FORCE_CREATE_REFLOG;
+	trace_printf_key(&trace_refs, "%d: %s %s -> %s (F=0x%x, T=0x%x) \"%s\"\n", i, refname,
+		o, n, flags, type, msg);
+}
+
+static void print_transaction(struct ref_transaction *transaction)
+{
+	int i;
+	trace_printf_key(&trace_refs, "transaction {\n");
+	for (i = 0; i < transaction->nr; i++) {
+		struct ref_update *u = transaction->updates[i];
+		print_update(i, u->refname, &u->old_oid, &u->new_oid, u->flags,
+			     u->type, u->msg);
+	}
+	trace_printf_key(&trace_refs, "}\n");
+}
+
+static int debug_transaction_finish(struct ref_store *refs,
+				    struct ref_transaction *transaction,
+				    struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
+	int res;
+	transaction->ref_store = drefs->refs;
+	res = drefs->refs->be->transaction_finish(drefs->refs, transaction,
+						  err);
+	print_transaction(transaction);
+	trace_printf_key(&trace_refs, "finish: %d\n", res);
+	return res;
+}
+
+static int debug_transaction_abort(struct ref_store *refs,
+				   struct ref_transaction *transaction,
+				   struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
+	int res;
+	transaction->ref_store = drefs->refs;
+	res = drefs->refs->be->transaction_abort(drefs->refs, transaction, err);
+	return res;
+}
+
+static int debug_initial_transaction_commit(struct ref_store *refs,
+					    struct ref_transaction *transaction,
+					    struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
+	int res;
+	transaction->ref_store = drefs->refs;
+	res = drefs->refs->be->initial_transaction_commit(drefs->refs,
+							  transaction, err);
+	return res;
+}
+
+static int debug_pack_refs(struct ref_store *ref_store, unsigned int flags)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->pack_refs(drefs->refs, flags);
+	trace_printf_key(&trace_refs, "pack_refs: %d\n", res);
+	return res;
+}
+
+static int debug_create_symref(struct ref_store *ref_store,
+			       const char *ref_name, const char *target,
+			       const char *logmsg)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->create_symref(drefs->refs, ref_name, target,
+						 logmsg);
+	trace_printf_key(&trace_refs, "create_symref: %s -> %s \"%s\": %d\n", ref_name,
+		target, logmsg, res);
+	return res;
+}
+
+static int debug_delete_refs(struct ref_store *ref_store, const char *msg,
+			     struct string_list *refnames, unsigned int flags)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res =
+		drefs->refs->be->delete_refs(drefs->refs, msg, refnames, flags);
+	int i;
+	trace_printf_key(&trace_refs, "delete_refs {\n");
+	for (i = 0; i < refnames->nr; i++)
+		trace_printf_key(&trace_refs, "%s\n", refnames->items[i].string);
+	trace_printf_key(&trace_refs, "}: %d\n", res);
+	return res;
+}
+
+static int debug_rename_ref(struct ref_store *ref_store, const char *oldref,
+			    const char *newref, const char *logmsg)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->rename_ref(drefs->refs, oldref, newref,
+					      logmsg);
+	trace_printf_key(&trace_refs, "rename_ref: %s -> %s \"%s\": %d\n", oldref, newref,
+		logmsg, res);
+	return res;
+}
+
+static int debug_copy_ref(struct ref_store *ref_store, const char *oldref,
+			  const char *newref, const char *logmsg)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res =
+		drefs->refs->be->copy_ref(drefs->refs, oldref, newref, logmsg);
+	trace_printf_key(&trace_refs, "copy_ref: %s -> %s \"%s\": %d\n", oldref, newref,
+		logmsg, res);
+	return res;
+}
+
+struct debug_ref_iterator {
+	struct ref_iterator base;
+	struct ref_iterator *iter;
+};
+
+static int debug_ref_iterator_advance(struct ref_iterator *ref_iterator)
+{
+	struct debug_ref_iterator *diter =
+		(struct debug_ref_iterator *)ref_iterator;
+	int res = diter->iter->vtable->advance(diter->iter);
+	if (res)
+		trace_printf_key(&trace_refs, "iterator_advance: (%d)\n", res);
+	else
+		trace_printf_key(&trace_refs, "iterator_advance: %s (0)\n",
+			diter->iter->refname);
+
+	diter->base.ordered = diter->iter->ordered;
+	diter->base.refname = diter->iter->refname;
+	diter->base.oid = diter->iter->oid;
+	diter->base.flags = diter->iter->flags;
+	return res;
+}
+
+static int debug_ref_iterator_peel(struct ref_iterator *ref_iterator,
+				   struct object_id *peeled)
+{
+	struct debug_ref_iterator *diter =
+		(struct debug_ref_iterator *)ref_iterator;
+	int res = diter->iter->vtable->peel(diter->iter, peeled);
+	trace_printf_key(&trace_refs, "iterator_peel: %s: %d\n", diter->iter->refname, res);
+	return res;
+}
+
+static int debug_ref_iterator_abort(struct ref_iterator *ref_iterator)
+{
+	struct debug_ref_iterator *diter =
+		(struct debug_ref_iterator *)ref_iterator;
+	int res = diter->iter->vtable->abort(diter->iter);
+	trace_printf_key(&trace_refs, "iterator_abort: %d\n", res);
+	return res;
+}
+
+static struct ref_iterator_vtable debug_ref_iterator_vtable = {
+	debug_ref_iterator_advance, debug_ref_iterator_peel,
+	debug_ref_iterator_abort
+};
+
+static struct ref_iterator *
+debug_ref_iterator_begin(struct ref_store *ref_store, const char *prefix,
+			 unsigned int flags)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	struct ref_iterator *res =
+		drefs->refs->be->iterator_begin(drefs->refs, prefix, flags);
+	struct debug_ref_iterator *diter = xcalloc(1, sizeof(*diter));
+	base_ref_iterator_init(&diter->base, &debug_ref_iterator_vtable, 1);
+	diter->iter = res;
+	trace_printf_key(&trace_refs, "ref_iterator_begin: %s (0x%x)\n", prefix, flags);
+	return &diter->base;
+}
+
+static int debug_read_raw_ref(struct ref_store *ref_store, const char *refname,
+			      struct object_id *oid, struct strbuf *referent,
+			      unsigned int *type)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = 0;
+
+	oidcpy(oid, &null_oid);
+	res = drefs->refs->be->read_raw_ref(drefs->refs, refname, oid, referent,
+					    type);
+
+	if (res == 0) {
+		trace_printf_key(&trace_refs, "read_raw_ref: %s: %s (=> %s) type %x: %d\n",
+			refname, oid_to_hex(oid), referent->buf, *type, res);
+	} else {
+		trace_printf_key(&trace_refs, "read_raw_ref: %s: %d\n", refname, res);
+	}
+	return res;
+}
+
+static struct ref_iterator *
+debug_reflog_iterator_begin(struct ref_store *ref_store)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	struct ref_iterator *res =
+		drefs->refs->be->reflog_iterator_begin(drefs->refs);
+	trace_printf_key(&trace_refs, "for_each_reflog_iterator_begin\n");
+	return res;
+}
+
+struct debug_reflog {
+	const char *refname;
+	each_reflog_ent_fn *fn;
+	void *cb_data;
+};
+
+static int debug_print_reflog_ent(struct object_id *old_oid,
+				  struct object_id *new_oid,
+				  const char *committer, timestamp_t timestamp,
+				  int tz, const char *msg, void *cb_data)
+{
+	struct debug_reflog *dbg = (struct debug_reflog *)cb_data;
+	int ret;
+	char o[GIT_MAX_HEXSZ + 1] = "null";
+	char n[GIT_MAX_HEXSZ + 1] = "null";
+	if (old_oid)
+		oid_to_hex_r(o, old_oid);
+	if (new_oid)
+		oid_to_hex_r(n, new_oid);
+
+	ret = dbg->fn(old_oid, new_oid, committer, timestamp, tz, msg,
+		      dbg->cb_data);
+	trace_printf_key(&trace_refs, "reflog_ent %s (ret %d): %s -> %s, %s %ld \"%s\"\n",
+		dbg->refname, ret, o, n, committer, (long int)timestamp, msg);
+	return ret;
+}
+
+static int debug_for_each_reflog_ent(struct ref_store *ref_store,
+				     const char *refname, each_reflog_ent_fn fn,
+				     void *cb_data)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	struct debug_reflog dbg = {
+		.refname = refname,
+		.fn = fn,
+		.cb_data = cb_data,
+	};
+
+	int res = drefs->refs->be->for_each_reflog_ent(
+		drefs->refs, refname, &debug_print_reflog_ent, &dbg);
+	trace_printf_key(&trace_refs, "for_each_reflog: %s: %d\n", refname, res);
+	return res;
+}
+
+static int debug_for_each_reflog_ent_reverse(struct ref_store *ref_store,
+					     const char *refname,
+					     each_reflog_ent_fn fn,
+					     void *cb_data)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	struct debug_reflog dbg = {
+		.refname = refname,
+		.fn = fn,
+		.cb_data = cb_data,
+	};
+	int res = drefs->refs->be->for_each_reflog_ent_reverse(
+		drefs->refs, refname, &debug_print_reflog_ent, &dbg);
+	trace_printf_key(&trace_refs, "for_each_reflog_reverse: %s: %d\n", refname, res);
+	return res;
+}
+
+static int debug_reflog_exists(struct ref_store *ref_store, const char *refname)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->reflog_exists(drefs->refs, refname);
+	trace_printf_key(&trace_refs, "reflog_exists: %s: %d\n", refname, res);
+	return res;
+}
+
+static int debug_create_reflog(struct ref_store *ref_store, const char *refname,
+			       int force_create, struct strbuf *err)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->create_reflog(drefs->refs, refname,
+						 force_create, err);
+	trace_printf_key(&trace_refs, "create_reflog: %s: %d\n", refname, res);
+	return res;
+}
+
+static int debug_delete_reflog(struct ref_store *ref_store, const char *refname)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->delete_reflog(drefs->refs, refname);
+	trace_printf_key(&trace_refs, "delete_reflog: %s: %d\n", refname, res);
+	return res;
+}
+
+static int debug_reflog_expire(struct ref_store *ref_store, const char *refname,
+			       const struct object_id *oid, unsigned int flags,
+			       reflog_expiry_prepare_fn prepare_fn,
+			       reflog_expiry_should_prune_fn should_prune_fn,
+			       reflog_expiry_cleanup_fn cleanup_fn,
+			       void *policy_cb_data)
+{
+	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
+	int res = drefs->refs->be->reflog_expire(drefs->refs, refname, oid,
+						 flags, prepare_fn,
+						 should_prune_fn, cleanup_fn,
+						 policy_cb_data);
+	trace_printf_key(&trace_refs, "reflog_expire: %s: %d\n", refname, res);
+	return res;
+}
+
+struct ref_storage_be refs_be_debug = {
+	NULL,
+	"debug",
+	NULL,
+	debug_init_db,
+	debug_transaction_prepare,
+	debug_transaction_finish,
+	debug_transaction_abort,
+	debug_initial_transaction_commit,
+
+	debug_pack_refs,
+	debug_create_symref,
+	debug_delete_refs,
+	debug_rename_ref,
+	debug_copy_ref,
+
+	debug_ref_iterator_begin,
+	debug_read_raw_ref,
+
+	debug_reflog_iterator_begin,
+	debug_for_each_reflog_ent,
+	debug_for_each_reflog_ent_reverse,
+	debug_reflog_exists,
+	debug_create_reflog,
+	debug_delete_reflog,
+	debug_reflog_expire,
+};