Stop a cancelled backup at once under --skip-errors (closes #286)

After Ctrl-C or SIGTERM, phase 2 of a --skip-errors backup treated the
cancellation error from each remaining file like an unreadable file: it
opened the file, printed an error line, counted it as failed and moved
on to the next. The processing loop now checks for cancellation before
each file, and an error from a file once the run is cancelled stops the
run instead of being skipped. The loop check is what stops a run
cancelled while an empty file is open, since an empty file has no
chunks and nothing reads the context while it is backed up.

The --skip-errors test helper now takes the scan's context.

Model: opus-5-5

README.md

@@ -412,8 +412,7 @@ destination store.
 entirely. Remote storage is unaffected; the next backup will do a full
 scan and re-deduplicate against existing remote blobs, and the local
 index will re-bind to the currently configured storage destination.
-Use this after changing `storage_url`, or `s3.endpoint`, `s3.bucket` or
-`s3.prefix`, to a different destination.
+Use this after changing `storage_url` to a different destination.
 * `--force`: Skip confirmation prompt
 
 ---

TODO.md

@@ -22,34 +22,6 @@ the tag exists and is exercised; what is left is merging `next` to
 
 # Completed Steps
 
-- 2026-10-13: Made an exclude pattern starting with `**/` also match
-  directly under the snapshot path
-  ([issue #303](https://git.eeqj.de/sneak/vaultik/issues/303)).
-  `**/node_modules` and `**/*.pyc`, the patterns `config.example.yml`
-  uses, excluded `sub/node_modules` and `sub/y.pyc` but backed up
-  `node_modules/` and `x.pyc` at the top of the path, since the pattern
-  required a `/` before the name. As in gitignore, such a pattern now
-  matches at every depth, the top included.
-
-- 2026-10-12: Bound the local index to the destination an `s3.*` config
-  names ([issue #298](https://git.eeqj.de/sneak/vaultik/issues/298)).
-  Only `storage_url` was checked, so after `s3.bucket` or `s3.prefix`
-  changed, the next backup treated every chunk as already stored,
-  uploaded nothing, and completed a snapshot that could not be restored.
-  Without `storage_url`, the local index is now bound to `s3.endpoint`,
-  `s3.bucket` and `s3.prefix`, and a change is refused as a changed
-  `storage_url` is.
-
-- 2026-10-12: Rejected a retention duration longer than about 292 years
-  ([issue #289](https://git.eeqj.de/sneak/vaultik/issues/289)). The
-  number given to `--older-than` or `--keep-newer-than` was multiplied
-  by the length of its unit with no limit, so from `293y`, `15251w`,
-  `3559mo` or `106752d`, or a sum of parts such as `200y200y`, the
-  result wrapped to a negative duration. The cutoff then lay in the
-  future, every snapshot of the name was deleted, the one just made
-  included, and the command exited 0. Such a duration is now rejected
-  as invalid and nothing is deleted.
-
 - 2026-10-08: Made a backup cancelled under `--skip-errors` stop at once
   ([issue #286](https://git.eeqj.de/sneak/vaultik/issues/286)). After
   Ctrl-C or SIGTERM, phase 2 treated the cancellation error from each

internal/snapshot/exclude_test.go

@@ -531,50 +531,3 @@ func TestExcludePatterns_UnanchoredPatternFile(t *testing.T) {
 	require.Equal(t, 1, result.FilesScanned,
 		"Unanchored pattern for file should match anywhere")
 }
-
-func TestExcludePatterns_DoubleStarDirectoryAtEveryDepth(t *testing.T) {
-	t.Parallel()
-
-	// As in gitignore, a leading **/ also matches directly under the source dir
-	fs := setupAnchoredTestFS(t)
-
-	scanner, repos, cleanup := createTestScanner(t, fs, []string{"**/projectname"})
-	defer cleanup()
-
-	ctx := context.Background()
-	createSnapshotRecord(ctx, t, repos, "test-snapshot")
-
-	result, err := scanner.Scan(ctx, "/backup", "test-snapshot")
-	require.NoError(t, err)
-
-	// **/projectname should exclude BOTH:
-	// - /backup/projectname/file.txt
-	// - /backup/otherproject/projectname/file.txt
-	// Total files: 4, excluded: 2
-	require.Equal(t, 2, result.FilesScanned,
-		"**/ directory pattern should match at the top level and nested")
-}
-
-func TestExcludePatterns_DoubleStarFileAtEveryDepth(t *testing.T) {
-	t.Parallel()
-
-	// As in gitignore, a leading **/ also matches directly under the source dir
-	fs := setupAnchoredTestFS(t)
-
-	scanner, repos, cleanup := createTestScanner(t, fs, []string{"**/*.txt"})
-	defer cleanup()
-
-	ctx := context.Background()
-	createSnapshotRecord(ctx, t, repos, "test-snapshot")
-
-	result, err := scanner.Scan(ctx, "/backup", "test-snapshot")
-	require.NoError(t, err)
-
-	// **/*.txt should exclude ALL .txt files:
-	// - /backup/file.txt
-	// - /backup/projectname/file.txt
-	// - /backup/otherproject/projectname/file.txt
-	// Total files: 4, excluded: 3
-	require.Equal(t, 1, result.FilesScanned,
-		"**/ file pattern should match at the top level and nested")
-}

internal/snapshot/scanner.go

@@ -2013,14 +2013,6 @@ func compileExcludePatterns(patterns []string) []compiledPattern {
 		// Remove trailing slash if present (directory indicator)
 		pattern = strings.TrimSuffix(pattern, "/")
 
-		// A leading "**/" demands a "/" before the name and so misses an
-		// entry directly under the source path. An unanchored pattern
-		// already matches at every depth, so drop the prefix: as in
-		// gitignore, "**/x" then also matches a top-level "x".
-		if !anchored {
-			pattern = strings.TrimPrefix(pattern, "**/")
-		}
-
 		// Compile the glob pattern
 		// For patterns without path separators, we need to match them as components
 		// e.g., ".git" should match ".git" anywhere in the path

internal/vaultik/helpers.go

@@ -3,7 +3,6 @@ package vaultik
 import (
 	"errors"
 	"fmt"
-	"math"
 	"regexp"
 	"strconv"
 	"strings"
@@ -48,10 +47,6 @@ const (
 	year  = 365 * day
 )
 
-// maxDuration is the largest value a time.Duration can hold, about 292
-// years.
-const maxDuration = time.Duration(math.MaxInt64)
-
 // A snapshot ID split on "_" has at least a hostname and a trailing
 // timestamp.
 const minSnapshotIDParts = 2
@@ -150,10 +145,10 @@ func parseSnapshotName(snapshotID, hostname string) string {
 // parseDuration parses a duration string with support for human-friendly units:
 // d/day/days, w/week/weeks, mo/month/months, y/year/years, plus standard Go
 // duration units. Following Go, m is minutes and mo is months. A bare number,
-// an unknown unit, a negative value, and a total longer than maxDuration are
-// all rejected. Outside the Go units the input must be whole numbers each
-// followed directly by a unit (2w3d), so 1.0y and 30 days are errors;
-// decimals work only in Go units (1.5h).
+// an unknown unit, and a negative value are all rejected. Outside the Go
+// units the input must be whole numbers each followed directly by a unit
+// (2w3d), so 1.0y and 30 days are errors; decimals work only in Go units
+// (1.5h).
 func parseDuration(s string) (time.Duration, error) {
 	if strings.HasPrefix(strings.TrimSpace(s), "-") {
 		return 0, errNegativeDuration
@@ -186,30 +181,19 @@ func parseDuration(s string) (time.Duration, error) {
 			return 0, fmt.Errorf("invalid number %q: %w", match[1], err)
 		}
 
-		var unitLength time.Duration
-
 		unit := strings.ToLower(match[2])
 		switch unit {
 		case "d", "day", "days":
-			unitLength = day
+			total += time.Duration(n) * day
 		case "w", "week", "weeks":
-			unitLength = week
+			total += time.Duration(n) * week
 		case "mo", "month", "months":
-			unitLength = month
+			total += time.Duration(n) * month
 		case "y", "year", "years":
-			unitLength = year
+			total += time.Duration(n) * year
 		default:
 			return 0, fmt.Errorf("%w %q", errUnknownTimeUnit, unit)
 		}
-
-		// Past maxDuration the sum wraps to a negative value, which would
-		// put the purge cutoff in the future.
-		if time.Duration(n) > (maxDuration-total)/unitLength {
-			return 0, fmt.Errorf("%w: %q is longer than about 292 years",
-				errInvalidDuration, s)
-		}
-
-		total += time.Duration(n) * unitLength
 	}
 
 	return total, nil

internal/vaultik/helpers_test.go

@@ -111,17 +111,6 @@ func TestParseDuration(t *testing.T) {
 		{"30 days", 0, true},
 		{"30 days ago", 0, true},
 		{"x7d", 0, true},
-		// The largest time.Duration is about 292 years. A larger value
-		// must be rejected, not wrapped to a negative one, which would
-		// put the cutoff in the future and select every snapshot.
-		{"292y", 292 * 365 * 24 * time.Hour, false},
-		{"293y", 0, true},
-		{"3559mo", 0, true},
-		{"15251w", 0, true},
-		{"106752d", 0, true},
-		{"2562048h", 0, true},
-		{"200y200y", 0, true},
-		{"292y6mo", 0, true},
 	}
 
 	for _, tt := range tests {

internal/vaultik/purge_per_name_test.go

@@ -267,29 +267,6 @@ func TestPurgeOlderThan_WithNameFilter(t *testing.T) {
 	assert.Contains(t, remaining, snapHomeT0)
 }
 
-func TestPurgeOlderThan_TooLargeDeletesNothing(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	snapshotIDs := []string{snapHomeT0, snapHomeT1}
-
-	v := setupPurgeTest(t, snapHostname, snapshotIDs)
-
-	err := v.PurgeSnapshotsWithOptions(&vaultik.SnapshotPurgeOptions{
-		OlderThan: "1000y",
-		Force:     true,
-	})
-	require.Error(t, err)
-
-	err = v.PurgeSnapshotsWithOptions(&vaultik.SnapshotPurgeOptions{
-		OlderThan: "292y",
-		Force:     true,
-	})
-	require.NoError(t, err)
-
-	assert.ElementsMatch(t, snapshotIDs, listRemainingSnapshots(t, v))
-}
-
 func TestPurgeKeepLatest_ThreeNames(t *testing.T) {
 	log.Initialize(log.Config{})
 	t.Parallel()

internal/vaultik/storage_bind.go

@@ -9,7 +9,7 @@ import (
 )
 
 // errStorageBindingMismatch is returned when the local index database is
-// bound to a different destination than the configured one.
+// bound to a different destination than the configured storage_url.
 var errStorageBindingMismatch = errors.New(
 	"local index is bound to a different backup destination")
 
@@ -24,9 +24,8 @@ var errStorageBindingMismatch = errors.New(
 //
 // Behaviour:
 //   - On first use (empty stored value), record the configured
-//     destination (storage_url, or the s3.* endpoint, bucket and
-//     prefix) and log the binding.
-//   - When the stored value matches the configured destination, do
+//     storage_url and log the binding.
+//   - When the stored value matches the configured storage_url, do
 //     nothing and return nil.
 //   - When the two differ, refuse with an error that tells the user
 //     how to recover (revert the config, or run `vaultik database
@@ -47,10 +46,12 @@ func (v *Vaultik) EnsureStorageBinding() error {
 
 	configured := v.Config.StorageURL
 	if configured == "" {
-		// The s3.* form: bind on its endpoint, bucket and prefix,
-		// written the way storage_url would name the same destination.
-		s3 := v.Config.S3
-		configured = "s3://" + s3.Bucket + "/" + s3.Prefix + "?endpoint=" + s3.Endpoint
+		// Some legacy configs still use the split s3.* keys instead of
+		// storage_url. Falling back to a synthetic URL for those would
+		// hide the fact that the binding is loose. Instead, treat
+		// unset as "nothing to bind against" — the check is
+		// necessarily best-effort for those configs.
+		return nil
 	}
 
 	stored, err := v.Repositories.LocalMeta.Get(v.ctx, database.LocalMetaKeyStorageURL)
@@ -95,8 +96,7 @@ func buildBindingMismatchMessage(stored, configured string) string {
 		"future snapshots referencing blobs that don't exist at the new destination.\n" +
 		"\n" +
 		"To proceed, either:\n" +
-		"  - revert storage_url (or the s3.* endpoint, bucket and prefix) in your\n" +
-		"    config to the bound destination, or\n" +
+		"  - revert storage_url in your config to the bound destination, or\n" +
 		"  - run 'vaultik database delete' to discard the local index and rebuild it\n" +
 		"    from a fresh full backup against the new destination"
 }

internal/vaultik/storage_bind_test.go

@@ -76,51 +76,3 @@ func TestEnsureStorageBinding_MismatchRefuses(t *testing.T) {
 	assert.Contains(t, err.Error(), "file:///mnt/backups/new")
 	assert.Contains(t, err.Error(), "vaultik database delete")
 }
-
-// A config with no storage_url names its destination with s3.endpoint,
-// s3.bucket and s3.prefix; a change to any of them must be refused just
-// as a changed storage_url is.
-func TestEnsureStorageBinding_S3FieldsChangeRefuses(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	bound := config.S3Config{
-		Endpoint: "https://s3.example.com",
-		Bucket:   "bucket-a",
-		Prefix:   "backups",
-	}
-
-	tests := []struct {
-		name    string
-		changed config.S3Config
-	}{
-		{"bucket", config.S3Config{
-			Endpoint: bound.Endpoint, Bucket: "bucket-b", Prefix: bound.Prefix,
-		}},
-		{"prefix", config.S3Config{
-			Endpoint: bound.Endpoint, Bucket: bound.Bucket, Prefix: "other",
-		}},
-		{"endpoint", config.S3Config{
-			Endpoint: "https://s3.other.com", Bucket: bound.Bucket, Prefix: bound.Prefix,
-		}},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			t.Parallel()
-
-			tv, _ := buildBindTestVaultik(t, "")
-
-			tv.Config.S3 = bound
-			require.NoError(t, tv.EnsureStorageBinding(), "first use binds")
-			require.NoError(t, tv.EnsureStorageBinding(), "same destination passes")
-
-			tv.Config.S3 = tt.changed
-			err := tv.EnsureStorageBinding()
-			require.Error(t, err)
-			assert.Contains(t, err.Error(),
-				"local index is bound to a different backup destination")
-			assert.Contains(t, err.Error(), "vaultik database delete")
-		})
-	}
-}