New remove option : -u / --unneeded (FS#6505).

With --unneeded option 'pacman -R' doesn't stop in case of dependency error;
it removes the needed-dependency targets from the target-list instead.  See
also: http://archlinux.org/pipermail/pacman-dev/2007-October/009653.html .

The patch also adds a new causingpkg field to pmdepmissing_t which indicates
the to-be-removed package which would cause a dependency break. This is
needed, because miss->depend.name may be a provision. miss->causingpkg will
be useful in -R dependency error messages too.

[Xavier: renamed inducer to causingpkg, removed the _alpm_pkgname_pkg_cmp
helper function as requested by Aaron. This might be added by a further
commit.  Other small cleanups, updated manpage and bash completion.]

Signed-off-by: Chantry Xavier <shiningxc@gmail.com>

1 files changed, 25 insertions, 1 deletions

diff --git a/lib/libalpm/remove.c b/lib/libalpm/remove.c
index 10a055bb..a0c308fb 100644
--- a/lib/libalpm/remove.c
+++ b/lib/libalpm/remove.c
@@ -124,11 +124,35 @@ int _alpm_remove_prepare(pmtrans_t *trans, pmdb_t *db, alpm_list_t **data)
 					alpm_list_free(lp);
 					lp = alpm_checkdeps(db, 1, trans->packages, NULL);
 				}
+			} else if (trans->flags & PM_TRANS_FLAG_UNNEEDED) {
+				/* Remove needed packages (which break dependencies) from the target list */
+				while(lp != NULL) {
+					alpm_list_t *i;
+					for(i = lp; i; i = i->next) {
+						pmdepmissing_t *miss = (pmdepmissing_t *)i->data;
+						void *vpkg;
+						pmpkg_t *pkg;
+						pmpkg_t *dummy = _alpm_pkg_new(miss->causingpkg, NULL);
+						trans->packages = alpm_list_remove(trans->packages, dummy,
+								_alpm_pkg_cmp, &vpkg);
+						_alpm_pkg_free(dummy);
+						pkg = vpkg;
+						if(pkg) {
+							_alpm_log(PM_LOG_WARNING, "removing %s from the target-list\n",
+									alpm_pkg_get_name(pkg));
+							_alpm_pkg_free(pkg);
+						}
+					}
+					alpm_list_free_inner(lp, (alpm_list_fn_free)_alpm_depmiss_free);
+					alpm_list_free(lp);
+					lp = alpm_checkdeps(db, 1, trans->packages, NULL);
+				}
 			} else {
 				if(data) {
 					*data = lp;
 				} else {
-					FREELIST(lp);
+					alpm_list_free_inner(lp, (alpm_list_fn_free)_alpm_depmiss_free);
+					alpm_list_free(lp);
 				}
 				RET_ERR(PM_ERR_UNSATISFIED_DEPS, -1);
 			}