{"record":{"id":"9355330145468d71","repo":"lionsoul2014/ip2region","slug":"open-xdb-file-s-w-935533","errorCode":null,"errorMessage":"open xdb file `%s`: %w","messagePattern":"open xdb file `(.+?)`: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"binding/golang/xdb/util.go","lineNumber":180,"sourceCode":"\t// to sure that the MaxFilePointer does no overflow\n\tstat, err := handle.Stat()\n\tif err != nil {\n\t\treturn fmt.Errorf(\"file stat: %w\", err)\n\t}\n\n\tmaxFilePtr := (int64(1) << (runtimePtrBytes * 8)) - 1\n\tif stat.Size() > maxFilePtr {\n\t\treturn fmt.Errorf(\"xdb file exceeds the maximum supported bytes: %d\", maxFilePtr)\n\t}\n\n\treturn nil\n}\n\n// VerifyFromFile check Verify for details\nfunc VerifyFromFile(dbFile string) error {\n\thandle, err := os.OpenFile(dbFile, os.O_RDONLY, 0600)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"open xdb file `%s`: %w\", dbFile, err)\n\t}\n\tdefer handle.Close()\n\n\treturn Verify(handle)\n}\n\n// LoadHeader load the header info from the specified handle\nfunc LoadHeader(handle io.ReadSeeker) (*Header, error) {\n\t_, err := handle.Seek(0, 0)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"seek to the header: %w\", err)\n\t}\n\n\tvar buff = make([]byte, HeaderInfoLength)\n\trLen, err := handle.Read(buff)\n\tif err != nil {\n\t\treturn nil, err\n\t}","sourceCodeStart":162,"sourceCodeEnd":198,"githubUrl":"https://github.com/lionsoul2014/ip2region/blob/c1a1fc7d5941760db3f8431dc05c48cf7f0e30a1/binding/golang/xdb/util.go#L162-L198","documentation":"VerifyFromFile opens the xdb file read-only before delegating to Verify; if os.OpenFile fails, the OS error is wrapped with the file path as \"open xdb file `%s`: %w\". This is a path/permission problem, not a data-format problem.","triggerScenarios":"VerifyFromFile(\"/path/ip2region.xdb\") with a nonexistent path (ENOENT), no read permission (EACCES), the path being a directory (EISDIR), or a bad symlink.","commonSituations":"Wrong relative path because the working directory differs in deployment; missing xdb file in a container image; running the service as a user without read access; typo'd environment variable for the db path.","solutions":["Print the resolved absolute path and check it exists with os.Stat before calling VerifyFromFile","Fix file permissions (chmod/chown) or run as a user with read access","Fix the path/environment variable pointing at the xdb file, including packaging the file in the image","Confirm the path is a file, not a directory"],"exampleFix":"// before\nerr := xdb.VerifyFromFile(os.Getenv(\"XDB_PATH\")) // open xdb file ``: no such file or directory\n// after\nxdbPath := os.Getenv(\"XDB_PATH\")\nif xdbPath == \"\" { xdbPath = \"./ip2region.xdb\" }\nif _, err := os.Stat(xdbPath); err != nil { log.Fatalf(\"xdb not found at %s\", xdbPath) }\nerr = xdb.VerifyFromFile(xdbPath)","handlingStrategy":"validation","validationCode":"func resolveXDB(path string) (string, error) {\n    abs, err := filepath.Abs(path)\n    if err != nil { return \"\", err }\n    info, err := os.Stat(abs)\n    if err != nil { return \"\", fmt.Errorf(\"xdb %s: %w\", abs, err) }\n    if info.IsDir() { return \"\", fmt.Errorf(\"%s is a directory\", abs) }\n    f, err := os.OpenFile(abs, os.O_RDONLY, 0600)\n    if err != nil { return \"\", err }\n    f.Close()\n    return abs, nil\n}","typeGuard":null,"tryCatchPattern":"if err := xdb.VerifyFromFile(dbPath); err != nil {\n    var pe *os.PathError\n    if errors.As(err, &pe) {\n        return fmt.Errorf(\"cannot open xdb %s: %v (check path/permissions)\", pe.Path, pe.Err)\n    }\n    return err\n}","preventionTips":["Resolve the xdb path to an absolute path at startup and fail fast if missing","Package the xdb file inside container images and verify after build","Give the service user read permission on the data file","Log the absolute path in the error to catch working-directory assumptions"],"tags":["go","filesystem","file-not-found","permissions"],"backgroundTag":"file-open-failed","analyzedSha":"c1a1fc7d5941760db3f8431dc05c48cf7f0e30a1","analyzedAt":"2026-09-02T16:58:39.988Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-09T21:17:11.164Z"}