migrate filename glob helpers to internal

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

internal/archive/zip_file_manifest.go

@@ -2,7 +2,6 @@ package archive
 
 import (
 	"fmt"
-	"github.com/anchore/syft/syft/file"
 	"os"
 	"sort"
 	"strings"
@@ -49,7 +48,7 @@ func (z ZipFileManifest) GlobMatch(patterns ...string) []string {
 			// so that glob logic is consistent inside and outside of ZIP archives
 			normalizedEntry := normalizeZipEntryName(entry)
 
-			if file.GlobMatch(pattern, normalizedEntry) {
+			if internal.FileNameGlobMatch(pattern, normalizedEntry) {
 				uniqueMatches.Add(entry)
 			}
 		}

internal/filename_glob_match.go

@@ -0,0 +1,46 @@
+package internal
+
+// FileNameGlobMatch evaluates the given glob pattern against the given "name" string, indicating if there is a match or not.
+// Source: https://research.swtch.com/glob.go
+func FileNameGlobMatch(pattern, name string) bool {
+	px := 0
+	nx := 0
+	nextPx := 0
+	nextNx := 0
+	for px < len(pattern) || nx < len(name) {
+		if px < len(pattern) {
+			c := pattern[px]
+			switch c {
+			default: // ordinary character
+				if nx < len(name) && name[nx] == c {
+					px++
+					nx++
+					continue
+				}
+			case '?': // single-character wildcard
+				if nx < len(name) {
+					px++
+					nx++
+					continue
+				}
+			case '*': // zero-or-more-character wildcard
+				// Try to match at nx.
+				// If that doesn't work out,
+				// restart at nx+1 next.
+				nextPx = px
+				nextNx = nx + 1
+				px++
+				continue
+			}
+		}
+		// Mismatch. Maybe restart.
+		if 0 < nextNx && nextNx <= len(name) {
+			px = nextPx
+			nx = nextNx
+			continue
+		}
+		return false
+	}
+	// Matched all of pattern to all of name. Success.
+	return true
+}

internal/filename_glob_match_test.go

@@ -0,0 +1,39 @@
+package internal
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestGlobMatch(t *testing.T) {
+	var tests = []struct {
+		pattern string
+		data    string
+		ok      bool
+	}{
+		{"", "", true},
+		{"x", "", false},
+		{"", "x", false},
+		{"abc", "abc", true},
+		{"*", "abc", true},
+		{"*c", "abc", true},
+		{"*b", "abc", false},
+		{"a*", "abc", true},
+		{"b*", "abc", false},
+		{"a*", "a", true},
+		{"*a", "a", true},
+		{"a*b*c*d*e*", "axbxcxdxe", true},
+		{"a*b*c*d*e*", "axbxcxdxexxx", true},
+		{"a*b?c*x", "abxbbxdbxebxczzx", true},
+		{"a*b?c*x", "abxbbxdbxebxczzy", false},
+		{"a*a*a*a*b", strings.Repeat("a", 100), false},
+		{"*x", "xxx", true},
+		{"/home/place/**", "/home/place/a/thing", true},
+	}
+
+	for _, test := range tests {
+		if FileNameGlobMatch(test.pattern, test.data) != test.ok {
+			t.Errorf("failed glob='%s' data='%s'", test.pattern, test.data)
+		}
+	}
+}