xml_parser.go 4.7 KB

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  1. package plist
  2. import (
  3. "encoding/base64"
  4. "encoding/xml"
  5. "errors"
  6. "fmt"
  7. "io"
  8. "runtime"
  9. "strings"
  10. "time"
  11. )
  12. type xmlPlistParser struct {
  13. reader io.Reader
  14. xmlDecoder *xml.Decoder
  15. whitespaceReplacer *strings.Replacer
  16. ntags int
  17. }
  18. func (p *xmlPlistParser) parseDocument() (pval cfValue, parseError error) {
  19. defer func() {
  20. if r := recover(); r != nil {
  21. if _, ok := r.(runtime.Error); ok {
  22. panic(r)
  23. }
  24. if _, ok := r.(invalidPlistError); ok {
  25. parseError = r.(error)
  26. } else {
  27. // Wrap all non-invalid-plist errors.
  28. parseError = plistParseError{"XML", r.(error)}
  29. }
  30. }
  31. }()
  32. for {
  33. if token, err := p.xmlDecoder.Token(); err == nil {
  34. if element, ok := token.(xml.StartElement); ok {
  35. pval = p.parseXMLElement(element)
  36. if p.ntags == 0 {
  37. panic(invalidPlistError{"XML", errors.New("no elements encountered")})
  38. }
  39. return
  40. }
  41. } else {
  42. // The first XML parse turned out to be invalid:
  43. // we do not have an XML property list.
  44. panic(invalidPlistError{"XML", err})
  45. }
  46. }
  47. }
  48. func (p *xmlPlistParser) parseXMLElement(element xml.StartElement) cfValue {
  49. var charData xml.CharData
  50. switch element.Name.Local {
  51. case "plist":
  52. p.ntags++
  53. for {
  54. token, err := p.xmlDecoder.Token()
  55. if err != nil {
  56. panic(err)
  57. }
  58. if el, ok := token.(xml.EndElement); ok && el.Name.Local == "plist" {
  59. break
  60. }
  61. if el, ok := token.(xml.StartElement); ok {
  62. return p.parseXMLElement(el)
  63. }
  64. }
  65. return nil
  66. case "string":
  67. p.ntags++
  68. err := p.xmlDecoder.DecodeElement(&charData, &element)
  69. if err != nil {
  70. panic(err)
  71. }
  72. return cfString(charData)
  73. case "integer":
  74. p.ntags++
  75. err := p.xmlDecoder.DecodeElement(&charData, &element)
  76. if err != nil {
  77. panic(err)
  78. }
  79. s := string(charData)
  80. if len(s) == 0 {
  81. panic(errors.New("invalid empty <integer/>"))
  82. }
  83. if s[0] == '-' {
  84. s, base := unsignedGetBase(s[1:])
  85. n := mustParseInt("-"+s, base, 64)
  86. return &cfNumber{signed: true, value: uint64(n)}
  87. } else {
  88. s, base := unsignedGetBase(s)
  89. n := mustParseUint(s, base, 64)
  90. return &cfNumber{signed: false, value: n}
  91. }
  92. case "real":
  93. p.ntags++
  94. err := p.xmlDecoder.DecodeElement(&charData, &element)
  95. if err != nil {
  96. panic(err)
  97. }
  98. n := mustParseFloat(string(charData), 64)
  99. return &cfReal{wide: true, value: n}
  100. case "true", "false":
  101. p.ntags++
  102. p.xmlDecoder.Skip()
  103. b := element.Name.Local == "true"
  104. return cfBoolean(b)
  105. case "date":
  106. p.ntags++
  107. err := p.xmlDecoder.DecodeElement(&charData, &element)
  108. if err != nil {
  109. panic(err)
  110. }
  111. t, err := time.ParseInLocation(time.RFC3339, string(charData), time.UTC)
  112. if err != nil {
  113. panic(err)
  114. }
  115. return cfDate(t)
  116. case "data":
  117. p.ntags++
  118. err := p.xmlDecoder.DecodeElement(&charData, &element)
  119. if err != nil {
  120. panic(err)
  121. }
  122. str := p.whitespaceReplacer.Replace(string(charData))
  123. l := base64.StdEncoding.DecodedLen(len(str))
  124. bytes := make([]uint8, l)
  125. l, err = base64.StdEncoding.Decode(bytes, []byte(str))
  126. if err != nil {
  127. panic(err)
  128. }
  129. return cfData(bytes[:l])
  130. case "dict":
  131. p.ntags++
  132. var key *string
  133. keys := make([]string, 0, 32)
  134. values := make([]cfValue, 0, 32)
  135. for {
  136. token, err := p.xmlDecoder.Token()
  137. if err != nil {
  138. panic(err)
  139. }
  140. if el, ok := token.(xml.EndElement); ok && el.Name.Local == "dict" {
  141. if key != nil {
  142. panic(errors.New("missing value in dictionary"))
  143. }
  144. break
  145. }
  146. if el, ok := token.(xml.StartElement); ok {
  147. if el.Name.Local == "key" {
  148. var k string
  149. p.xmlDecoder.DecodeElement(&k, &el)
  150. key = &k
  151. } else {
  152. if key == nil {
  153. panic(errors.New("missing key in dictionary"))
  154. }
  155. keys = append(keys, *key)
  156. values = append(values, p.parseXMLElement(el))
  157. key = nil
  158. }
  159. }
  160. }
  161. if len(keys) == 1 && keys[0] == "CF$UID" && len(values) == 1 {
  162. if integer, ok := values[0].(*cfNumber); ok {
  163. return cfUID(integer.value)
  164. }
  165. }
  166. return &cfDictionary{keys: keys, values: values}
  167. case "array":
  168. p.ntags++
  169. values := make([]cfValue, 0, 10)
  170. for {
  171. token, err := p.xmlDecoder.Token()
  172. if err != nil {
  173. panic(err)
  174. }
  175. if el, ok := token.(xml.EndElement); ok && el.Name.Local == "array" {
  176. break
  177. }
  178. if el, ok := token.(xml.StartElement); ok {
  179. values = append(values, p.parseXMLElement(el))
  180. }
  181. }
  182. return &cfArray{values}
  183. }
  184. err := fmt.Errorf("encountered unknown element %s", element.Name.Local)
  185. if p.ntags == 0 {
  186. // If out first XML tag is invalid, it might be an openstep data element, ala <abab> or <0101>
  187. panic(invalidPlistError{"XML", err})
  188. }
  189. panic(err)
  190. }
  191. func newXMLPlistParser(r io.Reader) *xmlPlistParser {
  192. return &xmlPlistParser{r, xml.NewDecoder(r), strings.NewReplacer("\t", "", "\n", "", " ", "", "\r", ""), 0}
  193. }