Reorganize code for one-at-a-time resolving

This change reorganizes the internal code so that packages are
resolved one at a time instead of all at once from a list.  This will
allow a future checkin to prompt the user to see if they'd rather
remove unresolvable packages from the transaction and continue, or
fail the transaction.  This change does not affect the actual behavior
of libalpm and all tests pass without changes.

Signed-off-by: Bryan Ischo <bryan@ischo.com>
Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 36 insertions, 11 deletions

diff --git a/lib/libalpm/sync.c b/lib/libalpm/sync.c
index b458874d..5e5ca92e 100644
--- a/lib/libalpm/sync.c
+++ b/lib/libalpm/sync.c
@@ -399,6 +399,7 @@ int _alpm_sync_prepare(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t *dbs_sync
 {
 	alpm_list_t *deps = NULL;
 	alpm_list_t *list = NULL, *remove = NULL; /* allow checkdeps usage with trans->packages */
+	alpm_list_t *unresolvable = NULL;
 	alpm_list_t *i, *j;
 	int ret = 0;
 
@@ -411,15 +412,13 @@ int _alpm_sync_prepare(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t *dbs_sync
 		*data = NULL;
 	}
 
-	for(i = trans->packages; i; i = i->next) {
-		pmsyncpkg_t *sync = i->data;
-		list = alpm_list_add(list, sync->pkg);
-	}
-
-	if(!(trans->flags & PM_TRANS_FLAG_NODEPS)) {
-		/* store a pointer to the last original target so we can tell what was
-		 * pulled by resolvedeps */
-		alpm_list_t *pulled = alpm_list_last(list);
+	if(trans->flags & PM_TRANS_FLAG_NODEPS) {
+		for(i = trans->packages; i; i = i->next) {
+			pmsyncpkg_t *sync = i->data;
+			list = alpm_list_add(list, sync->pkg);
+		}
+	} else {
+		/* Build up list by repeatedly resolving each transaction package */
 		/* Resolve targets dependencies */
 		EVENT(trans, PM_TRANS_EVT_RESOLVEDEPS_START, NULL, NULL);
 		_alpm_log(PM_LOG_DEBUG, "resolving target's dependencies\n");
@@ -432,14 +431,39 @@ int _alpm_sync_prepare(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t *dbs_sync
 			}
 		}
 
-		if(_alpm_resolvedeps(db_local, dbs_sync, list, remove, data) == -1) {
+		/* Resolve packages in the transaction one at a time, in addtion
+		   building up a list of packages which could not be resolved. */
+		for(i = trans->packages; i; i = i->next) {
+			pmpkg_t *pkg = ((pmsyncpkg_t *) i->data)->pkg;
+			if(_alpm_resolvedeps(db_local, dbs_sync, pkg, &list, remove, data) == -1) {
+				unresolvable = alpm_list_add(unresolvable, pkg);
+			}
+			/* Else, [list] now additionally contains [pkg] and all of its
+			   dependencies not already on the list */
+		}
+
+		/* If there were unresolvable top-level packages, fail the
+		   transaction. */
+		if(unresolvable != NULL) {
 			/* pm_errno is set by resolvedeps */
 			ret = -1;
 			goto cleanup;
 		}
 
-		for(i = pulled->next; i; i = i->next) {
+		/* Add all packages which were "pulled" (i.e. weren't already in the
+		   transaction) to the transaction in pmsyncpkg_t structures */
+		for(i = list; i; i = i->next) {
 			pmpkg_t *spkg = i->data;
+			for(j = trans->packages; j; j = j->next) {
+				if(_alpm_pkg_cmp(spkg, ((pmsyncpkg_t *) j->data)->pkg) == 0) {
+					spkg = NULL;
+					break;
+				}
+			}
+			if (spkg == NULL) {
+				continue;
+			}
+
 			pmsyncpkg_t *sync = _alpm_sync_new(PM_PKG_REASON_DEPEND, spkg, NULL);
 			if(sync == NULL) {
 				ret = -1;
@@ -627,6 +651,7 @@ int _alpm_sync_prepare(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t *dbs_sync
 cleanup:
 	alpm_list_free(list);
 	alpm_list_free(remove);
+	alpm_list_free(unresolvable);
 
 	return(ret);
 }