Fix dependency issues for preinst scripts

There is a problem with dependency order when installing packages. The key
problem revolves around the satisfy_dependencies_for() function which is
called from opkg_install_pkg just before the installation (and preinst)
happens.

The satisfy_dependencies_for() function calls pkg_hash_fetch_unsatisfied_dependencies()
which will only return packages which were previously not marked as
*going* to be installed at some point. For the purposes of
opkg_install_pkg() we really need to know which dependencies haven't been
installed yet.

This patch adds pkg_hash_fetch_satisfied_dependencies() which returns a
list of package dependencies. We can then directly check the status of
these and ensure any hard dependencies (not suggestions or recommendations)
are installed before returning.

Consider the situation (where -> means 'depends on'):

X -> A,E
A -> B,E
E -> B
B -> C

Currently X would install A and E. When installing A the packages B, E
and C would be marked as "to install". When the package B is considered
the second time (as a dependency of E rather than A), it would install
straight away even though C was not currently installed, just marked
as needing to be installed.

The patch changes the behaviour so B can't install until C really is installed.

This change is required to run the postinst scripts in the correct order.

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

git-svn-id: http://opkg.googlecode.com/svn/trunk@638 e8e0d7a0-c8d9-11dd-a880-a1081c7ac358

1 files changed, 21 insertions, 0 deletions

diff --git a/libopkg/opkg_install.c b/libopkg/opkg_install.c
index 3925f58..6ed67d2 100644
--- a/libopkg/opkg_install.c
+++ b/libopkg/opkg_install.c
@@ -77,6 +77,27 @@ satisfy_dependencies_for(pkg_t *pkg)
 
      if (ndepends <= 0) {
 	  pkg_vec_free(depends);
+	  depends = pkg_hash_fetch_satisfied_dependencies(pkg);
+
+	  for (i = 0; i < depends->len; i++) {
+	       dep = depends->pkgs[i];
+	       /* The package was uninstalled when we started, but another
+	          dep earlier in this loop may have depended on it and pulled
+	          it in, so check first. */
+	       if ((dep->state_status != SS_INSTALLED) && (dep->state_status != SS_UNPACKED)) {
+		    opkg_msg(DEBUG2,"Calling opkg_install_pkg.\n");
+		    err = opkg_install_pkg(dep, 0);
+		    /* mark this package as having been automatically installed to
+		     * satisfy a dependency */
+		    dep->auto_installed = 1;
+		    if (err) {
+			 pkg_vec_free(depends);
+			 return err;
+		    }
+	       }
+	  }
+
+	  pkg_vec_free(depends);
 	  return 0;
      }