[Libguestfs] [PATCH] List all missing dependencies at once

[Matthew Booth]

When a conversion requires a file from the config file which isn't present, we
currently die and report which file was missing. If there are many missing
dependencies, using this method to find them all would take multiple runs.

This change attempts to find all missing dependencies in the first run.
---
 lib/Sys/VirtV2V/Config.pm         |    9 ----
 lib/Sys/VirtV2V/GuestOS/RedHat.pm |   83 +++++++++++++++++++++++++++++--------
 2 files changed, 65 insertions(+), 27 deletions(-)

diff --git a/lib/Sys/VirtV2V/Config.pm b/lib/Sys/VirtV2V/Config.pm
index 5aa9917..3fff455 100644
--- a/lib/Sys/VirtV2V/Config.pm
+++ b/lib/Sys/VirtV2V/Config.pm
@@ -258,15 +258,6 @@ sub match_app
                          xml => $app->toString()))) unless (defined($path));
     $path = $path->getData();
 
-    my ($pathroot) = $dom->findnodes('/virt-v2v/path-root/text()');
-    my $abs = defined($pathroot) ? $pathroot->getData()."/$path" : $path;
-
-    die(user_message(__x("Matched local file {path} for {search}. ".
-                         "However, this file is not available.",
-                         path => $abs,
-                         search => _get_app_search($desc, $name, $arch))))
-        unless (-r $abs);
-
     my @deps;
     foreach my $dep ($app->findnodes('dep/text()')) {
         push(@deps, $dep->getData());
diff --git a/lib/Sys/VirtV2V/GuestOS/RedHat.pm b/lib/Sys/VirtV2V/GuestOS/RedHat.pm
index 1fd7d14..77d9332 100644
--- a/lib/Sys/VirtV2V/GuestOS/RedHat.pm
+++ b/lib/Sys/VirtV2V/GuestOS/RedHat.pm
@@ -484,12 +484,22 @@ sub add_kernel
         return undef;
     }
 
-    return undef if ($self->_newer_installed($app));
+    my @missing;
+    if (!$self->{g}->exists($self->_transfer_path($app))) {
+        push(@missing, $app);
+    } else {
+        return undef if ($self->_newer_installed($app));
+    }
 
     my $user_arch = $kernel_arch eq 'i686' ? 'i386' : $kernel_arch;
 
+    my @deps = $self->_get_deppaths(\@missing, $user_arch, @$depnames);
+
+    # We can't proceed if there are any files missing
+    _die_missing(@missing) if (@missing > 0);
+
     # Install any required kernel dependencies
-    $self->_install_rpms(1, $self->_get_deppaths($user_arch, @$depnames));
+    $self->_install_rpms(1, @deps);
 
     # Inspect the rpm to work out what kernel version it contains
     my $version;
@@ -514,6 +524,15 @@ sub add_kernel
     return $version;
 }
 
+sub _die_missing
+{
+    # We can't proceed if there are any files missing
+    die(user_message(__x("Conversion cannot proceed because the following ".
+                         "files referenced in the configuration file are ".
+                         "required, but missing: {list}",
+                         list => join(' ', @_))));
+}
+
 # Inspect the guest description to work out what kernel package is in use
 # Returns ($kernel_pkg, $kernel_arch)
 sub _discover_kernel
@@ -612,13 +631,19 @@ sub add_application
     my $config = $self->{config};
     my ($app, $deps) = $config->match_app($self->{desc}, $label, $user_arch);
 
-    # Nothing to do if it's already installed
-    return if ($self->_newer_installed($app));
+    my @missing;
+    if (!$self->{g}->exists($self->_transfer_path($app))) {
+        push(@missing, $app);
+    } else {
+        return if ($self->_newer_installed($app));
+    }
 
     my @install = ($app);
 
     # Add any dependencies which aren't already installed to the install set
-    push(@install, $self->_get_deppaths($user_arch, @$deps));
+    push(@install, $self->_get_deppaths(\@missing, $user_arch, @$deps));
+
+    _die_missing(@missing) if (@missing > 0);
 
     $self->_install_rpms(1, @install);
 }
@@ -740,7 +765,7 @@ sub _newer_installed
 sub _get_deppaths
 {
     my $self = shift;
-    my ($arch, @apps) = @_;
+    my ($missing, $arch, @apps) = @_;
 
     my $desc = $self->{desc};
     my $config = $self->{config};
@@ -749,16 +774,23 @@ sub _get_deppaths
     foreach my $app (@apps) {
         my ($path, $deps) = $config->match_app($desc, $app, $arch);
 
-        if (!$self->_newer_installed($path)) {
+        my $exists = $self->{g}->exists($self->_transfer_path($path));
+
+        if (!$exists) {
+            push(@$missing, $path);
+        }
+
+        if (!$exists || !$self->_newer_installed($path)) {
             $required{$path} = 1;
 
-            foreach my $deppath ($self->_get_deppaths($arch, @$deps)) {
+            foreach my $deppath ($self->_get_deppaths($missing,
+                                                      $arch, @$deps)) {
                 $required{$deppath} = 1;
             }
         }
 
-        # For x86_64, also check if there is any i386 version installed. If
-        # there is, check if it needs to be upgraded.
+        # For x86_64, also check if there is any i386 or i686 version installed.
+        # If there is, check if it needs to be upgraded.
         if ($arch eq 'x86_64') {
             $path = undef;
             $deps = undef;
@@ -768,18 +800,33 @@ sub _get_deppaths
                 ($path, $deps) = $config->match_app($desc, $app, 'i386');
             };
 
-            if (defined($path) && !$self->_newer_installed($path)) {
-                my ($name, undef, undef, undef, $arch) =
-                    $self->_get_nevra($path);
+            if (defined($path)) {
+                if (!$self->{g}->exists($self->_transfer_path($path))) {
+                    push(@$missing, $path);
 
-                my @installed = $self->_get_installed($name, $arch);
-                if (@installed > 0) {
-                    $required{$path} = 1;
-
-                    foreach my $deppath ($self->_get_deppaths('i386', @$deps)) {
+                    foreach my $deppath ($self->_get_deppaths($missing,
+                                                              'i386', @$deps))
+                    {
                         $required{$deppath} = 1;
                     }
                 }
+
+                elsif (!$self->_newer_installed($path)) {
+                    my ($name, undef, undef, undef, $arch) =
+                        $self->_get_nevra($path);
+
+                    my @installed = $self->_get_installed($name, $arch);
+
+                    if (@installed > 0) {
+                        $required{$path} = 1;
+
+                        foreach my $deppath
+                            ($self->_get_deppaths($missing, 'i386', @$deps))
+                        {
+                            $required{$deppath} = 1;
+                        }
+                    }
+                }
             }
         }
     }
-- 
1.6.6.1