1 files changed, 275 insertions, 0 deletions
diff --git a/vendor/github.com/container-orchestrated-devices/container-device-interface/pkg/cdi/cache.go b/vendor/github.com/container-orchestrated-devices/container-device-interface/pkg/cdi/cache.go
new file mode 100644
index 000000000..c4befc83e
--- /dev/null
+++ b/vendor/github.com/container-orchestrated-devices/container-device-interface/pkg/cdi/cache.go
@@ -0,0 +1,275 @@
+/*
+   Copyright © 2021 The CDI Authors
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package cdi
+
+import (
+	"path/filepath"
+	"sort"
+	"strings"
+	"sync"
+
+	"github.com/hashicorp/go-multierror"
+	oci "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/pkg/errors"
+)
+
+// Option is an option to change some aspect of default CDI behavior.
+type Option func(*Cache) error
+
+// Cache stores CDI Specs loaded from Spec directories.
+type Cache struct {
+	sync.Mutex
+	specDirs []string
+	specs    map[string][]*Spec
+	devices  map[string]*Device
+	errors   map[string][]error
+}
+
+// NewCache creates a new CDI Cache. The cache is populated from a set
+// of CDI Spec directories. These can be specified using a WithSpecDirs
+// option. The default set of directories is exposed in DefaultSpecDirs.
+func NewCache(options ...Option) (*Cache, error) {
+	c := &Cache{}
+
+	if err := c.Configure(options...); err != nil {
+		return nil, err
+	}
+	if len(c.specDirs) == 0 {
+		c.Configure(WithSpecDirs(DefaultSpecDirs...))
+	}
+
+	return c, c.Refresh()
+}
+
+// Configure applies options to the cache. Updates the cache if options have
+// changed.
+func (c *Cache) Configure(options ...Option) error {
+	if len(options) == 0 {
+		return nil
+	}
+
+	c.Lock()
+	defer c.Unlock()
+
+	for _, o := range options {
+		if err := o(c); err != nil {
+			return errors.Wrapf(err, "failed to apply cache options")
+		}
+	}
+
+	return nil
+}
+
+// Refresh rescans the CDI Spec directories and refreshes the Cache.
+func (c *Cache) Refresh() error {
+	var (
+		specs      = map[string][]*Spec{}
+		devices    = map[string]*Device{}
+		conflicts  = map[string]struct{}{}
+		specErrors = map[string][]error{}
+		result     []error
+	)
+
+	// collect errors per spec file path and once globally
+	collectError := func(err error, paths ...string) {
+		result = append(result, err)
+		for _, path := range paths {
+			specErrors[path] = append(specErrors[path], err)
+		}
+	}
+	// resolve conflicts based on device Spec priority (order of precedence)
+	resolveConflict := func(name string, dev *Device, old *Device) bool {
+		devSpec, oldSpec := dev.GetSpec(), old.GetSpec()
+		devPrio, oldPrio := devSpec.GetPriority(), oldSpec.GetPriority()
+		switch {
+		case devPrio > oldPrio:
+			return false
+		case devPrio == oldPrio:
+			devPath, oldPath := devSpec.GetPath(), oldSpec.GetPath()
+			collectError(errors.Errorf("conflicting device %q (specs %q, %q)",
+				name, devPath, oldPath), devPath, oldPath)
+			conflicts[name] = struct{}{}
+		}
+		return true
+	}
+
+	_ = scanSpecDirs(c.specDirs, func(path string, priority int, spec *Spec, err error) error {
+		path = filepath.Clean(path)
+		if err != nil {
+			collectError(errors.Wrapf(err, "failed to load CDI Spec"), path)
+			return nil
+		}
+
+		vendor := spec.GetVendor()
+		specs[vendor] = append(specs[vendor], spec)
+
+		for _, dev := range spec.devices {
+			qualified := dev.GetQualifiedName()
+			other, ok := devices[qualified]
+			if ok {
+				if resolveConflict(qualified, dev, other) {
+					continue
+				}
+			}
+			devices[qualified] = dev
+		}
+
+		return nil
+	})
+
+	for conflict := range conflicts {
+		delete(devices, conflict)
+	}
+
+	c.Lock()
+	defer c.Unlock()
+
+	c.specs = specs
+	c.devices = devices
+	c.errors = specErrors
+
+	if len(result) > 0 {
+		return multierror.Append(nil, result...)
+	}
+
+	return nil
+}
+
+// InjectDevices injects the given qualified devices to an OCI Spec. It
+// returns any unresolvable devices and an error if injection fails for
+// any of the devices.
+func (c *Cache) InjectDevices(ociSpec *oci.Spec, devices ...string) ([]string, error) {
+	var (
+		unresolved []string
+		specs      = map[*Spec]struct{}{}
+	)
+
+	if ociSpec == nil {
+		return devices, errors.Errorf("can't inject devices, nil OCI Spec")
+	}
+
+	c.Lock()
+	defer c.Unlock()
+
+	for _, device := range devices {
+		d := c.devices[device]
+		if d == nil {
+			unresolved = append(unresolved, device)
+			continue
+		}
+		if _, ok := specs[d.GetSpec()]; !ok {
+			specs[d.GetSpec()] = struct{}{}
+			d.GetSpec().ApplyEdits(ociSpec)
+		}
+		d.ApplyEdits(ociSpec)
+	}
+
+	if unresolved != nil {
+		return unresolved, errors.Errorf("unresolvable CDI devices %s",
+			strings.Join(devices, ", "))
+	}
+
+	return nil, nil
+}
+
+// GetDevice returns the cached device for the given qualified name.
+func (c *Cache) GetDevice(device string) *Device {
+	c.Lock()
+	defer c.Unlock()
+
+	return c.devices[device]
+}
+
+// ListDevices lists all cached devices by qualified name.
+func (c *Cache) ListDevices() []string {
+	var devices []string
+
+	c.Lock()
+	defer c.Unlock()
+
+	for name := range c.devices {
+		devices = append(devices, name)
+	}
+	sort.Strings(devices)
+
+	return devices
+}
+
+// ListVendors lists all vendors known to the cache.
+func (c *Cache) ListVendors() []string {
+	var vendors []string
+
+	c.Lock()
+	defer c.Unlock()
+
+	for vendor := range c.specs {
+		vendors = append(vendors, vendor)
+	}
+	sort.Strings(vendors)
+
+	return vendors
+}
+
+// ListClasses lists all device classes known to the cache.
+func (c *Cache) ListClasses() []string {
+	var (
+		cmap    = map[string]struct{}{}
+		classes []string
+	)
+
+	c.Lock()
+	defer c.Unlock()
+
+	for _, specs := range c.specs {
+		for _, spec := range specs {
+			cmap[spec.GetClass()] = struct{}{}
+		}
+	}
+	for class := range cmap {
+		classes = append(classes, class)
+	}
+	sort.Strings(classes)
+
+	return classes
+}
+
+// GetVendorSpecs returns all specs for the given vendor.
+func (c *Cache) GetVendorSpecs(vendor string) []*Spec {
+	c.Lock()
+	defer c.Unlock()
+
+	return c.specs[vendor]
+}
+
+// GetSpecErrors returns all errors encountered for the spec during the
+// last cache refresh.
+func (c *Cache) GetSpecErrors(spec *Spec) []error {
+	return c.errors[spec.GetPath()]
+}
+
+// GetErrors returns all errors encountered during the last
+// cache refresh.
+func (c *Cache) GetErrors() map[string][]error {
+	return c.errors
+}
+
+// GetSpecDirectories returns the CDI Spec directories currently in use.
+func (c *Cache) GetSpecDirectories() []string {
+	dirs := make([]string, len(c.specDirs))
+	copy(dirs, c.specDirs)
+	return dirs
+}