wasm: simplify platform-specific page size handling

Replace os.Getpagesize() calls with common.DefaultPageSize constant and remove redundant pagesize.go implementation. Simplify WASM-specific code by removing custom initialization and page size handling. Update tests to use the new constant.

Signed-off-by: Travis Cline <[email protected]>

Author: tmc

bucket_test.go

@@ -20,6 +20,7 @@ import (
 	bolt "go.etcd.io/bbolt"
 	berrors "go.etcd.io/bbolt/errors"
 	"go.etcd.io/bbolt/internal/btesting"
+	"go.etcd.io/bbolt/internal/common"
 )
 
 // Ensure that a bucket that gets a non-existent key returns nil.
@@ -1350,7 +1351,7 @@ func TestBucket_Stats(t *testing.T) {
 func TestBucket_Stats_RandomFill(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping test in short mode.")
-	} else if os.Getpagesize() != 4096 {
+	} else if common.DefaultPageSize != 4096 {
 		t.Skip("invalid page size for test")
 	}
 

cmd/bbolt/main_test.go

@@ -15,6 +15,7 @@ import (
 	"testing"
 
 	"go.etcd.io/bbolt/internal/btesting"
+	"go.etcd.io/bbolt/internal/common"
 	"go.etcd.io/bbolt/internal/guts_cli"
 
 	"github.com/stretchr/testify/assert"
@@ -41,7 +42,7 @@ func TestInfoCommand_Run(t *testing.T) {
 // Ensure the "stats" command executes correctly with an empty database.
 func TestStatsCommand_Run_EmptyDatabase(t *testing.T) {
 	// Ignore
-	if os.Getpagesize() != 4096 {
+	if common.DefaultPageSize != 4096 {
 		t.Skip("system does not use 4KB page size")
 	}
 
@@ -199,7 +200,7 @@ func TestPageItemCommand_Run(t *testing.T) {
 // Ensure the "stats" command can execute correctly.
 func TestStatsCommand_Run(t *testing.T) {
 	// Ignore
-	if os.Getpagesize() != 4096 {
+	if common.DefaultPageSize != 4096 {
 		t.Skip("system does not use 4KB page size")
 	}
 

db_test.go

@@ -147,7 +147,7 @@ func TestOpen_ErrInvalid(t *testing.T) {
 
 // Ensure that opening a file with two invalid versions returns ErrVersionMismatch.
 func TestOpen_ErrVersionMismatch(t *testing.T) {
-	if pageSize != os.Getpagesize() {
+	if pageSize != common.DefaultPageSize {
 		t.Skip("page size mismatch")
 	}
 
@@ -241,7 +241,7 @@ func TestOpen_ReadPageSize_FromMeta1_OS(t *testing.T) {
 
 	// Reopen data file.
 	db = btesting.MustOpenDBWithOption(t, path, nil)
-	require.Equalf(t, common.GetPagesize(), db.Info().PageSize, "check page size failed")
+	require.Equalf(t, common.DefaultPageSize, db.Info().PageSize, "check page size failed")
 }
 
 // Ensure that it can read the page size from the second meta page if the first one is invalid.
@@ -584,7 +584,7 @@ func TestDB_Open_ReadOnly_NoCreate(t *testing.T) {
 // TestOpen_BigPage checks the database uses bigger pages when
 // changing PageSize.
 func TestOpen_BigPage(t *testing.T) {
-	pageSize := os.Getpagesize()
+	pageSize := common.DefaultPageSize
 
 	db1 := btesting.MustCreateDBWithOption(t, &bolt.Options{PageSize: pageSize * 2})
 

internal/common/bolt_386.go

@@ -4,4 +4,4 @@ package common
 const MaxMapSize = 0x7FFFFFFF // 2GB
 
 // MaxAllocSize is the size used when creating array pointers.
-const MaxAllocSize = 0xFFFFFFF
+const MaxAllocSize = 0xFFFFFF

internal/common/bolt_wasm.go

@@ -3,22 +3,7 @@
 package common
 
 // MaxMapSize represents the largest mmap size supported by Bolt.
-// Reduced for WASM due to memory constraints.
-const MaxMapSize = 0x10000000 // 256MB
+const MaxMapSize = 0x10000000
 
 // MaxAllocSize is the size used when creating array pointers.
-// Slightly larger than MaxMapSize to accommodate metadata overhead.
-const MaxAllocSize = 0x10100000 // 257MB
-
-func init() {
-	// Override the default page size for WASM to use 4KB instead of 64KB.
-	// This reduces memory usage and makes behavior more consistent with other platforms.
-	// Note: Databases created with different page sizes are not compatible.
-	DefaultPageSize = 4096
-}
-
-// GetPagesize returns the system page size.
-// On WASM platforms, we always return 4KB as the page size.
-func GetPagesize() int {
-	return 4096
-}
+const MaxAllocSize = 0x10100000

internal/common/pagesize.go

@@ -16,6 +16,7 @@ import (
 	bolt "go.etcd.io/bbolt"
 	berrors "go.etcd.io/bbolt/errors"
 	"go.etcd.io/bbolt/internal/btesting"
+	"go.etcd.io/bbolt/internal/common"
 )
 
 // TestTx_Check_ReadOnly tests consistency checking on a ReadOnly database.
@@ -701,7 +702,7 @@ func TestTx_releaseRange(t *testing.T) {
 	// Set initial mmap size well beyond the limit we will hit in this
 	// test, since we are testing with long running read transactions
 	// and will deadlock if db.grow is triggered.
-	db := btesting.MustCreateDBWithOption(t, &bolt.Options{InitialMmapSize: os.Getpagesize() * 100})
+	db := btesting.MustCreateDBWithOption(t, &bolt.Options{InitialMmapSize: common.DefaultPageSize * 100})
 
 	bucket := "bucket"