make AllLocations accept a context (#2518)

The previous implementation would leak a goroutine if the caller of
AllLocations stopped iterating early. Now, accept a context so that the
caller can cancel the AllLocations iterator rather than leak the
goroutine.

Signed-off-by: Will Murphy <will.murphy@anchore.com>

syft/pkg/cataloger/binary/cataloger_test.go

@@ -1,6 +1,7 @@
 package binary
 
 import (
+	"context"
 	"errors"
 	"flag"
 	"fmt"
@@ -1237,7 +1238,7 @@ func (p *panicyResolver) RelativeFileByPath(_ file.Location, _ string) *file.Loc
 	return nil
 }
 
-func (p *panicyResolver) AllLocations() <-chan file.Location {
+func (p *panicyResolver) AllLocations(_ context.Context) <-chan file.Location {
 	return nil
 }
 

syft/pkg/cataloger/internal/pkgtest/observing_resolver.go

@@ -1,6 +1,7 @@
 package pkgtest
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"sort"
@@ -209,8 +210,8 @@ func (r *ObservingResolver) FileContentsByLocation(location file.Location) (io.R
 
 // For the remaining resolver methods...
 
-func (r *ObservingResolver) AllLocations() <-chan file.Location {
-	return r.decorated.AllLocations()
+func (r *ObservingResolver) AllLocations(ctx context.Context) <-chan file.Location {
+	return r.decorated.AllLocations(ctx)
 }
 
 func (r *ObservingResolver) HasPath(s string) bool {

syft/pkg/cataloger/nix/cataloger.go

@@ -4,6 +4,7 @@ Package nix provides a concrete Cataloger implementation for packages within the
 package nix
 
 import (
+	"context"
 	"fmt"
 
 	"github.com/bmatcuk/doublestar/v4"
@@ -31,7 +32,9 @@ func (c *StoreCataloger) Catalog(resolver file.Resolver) ([]pkg.Package, []artif
 	// we want to search for only directories, which isn't possible via the stereoscope API, so we need to apply the glob manually on all returned paths
 	var pkgs []pkg.Package
 	var filesByPath = make(map[string]*file.LocationSet)
-	for location := range resolver.AllLocations() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	for location := range resolver.AllLocations(ctx) {
 		matchesStorePath, err := doublestar.Match("**/nix/store/*", location.RealPath)
 		if err != nil {
 			return nil, nil, fmt.Errorf("failed to match nix store path: %w", err)

syft/pkg/cataloger/redhat/parse_rpm_db_test.go

@@ -1,6 +1,7 @@
 package redhat
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"testing"
@@ -34,7 +35,7 @@ func (r rpmdbTestFileResolverMock) FileContentsByLocation(location file.Location
 	panic("not implemented")
 }
 
-func (r rpmdbTestFileResolverMock) AllLocations() <-chan file.Location {
+func (r rpmdbTestFileResolverMock) AllLocations(_ context.Context) <-chan file.Location {
 	panic("not implemented")
 }