iter_object.go 5.8 KB

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  1. package jsoniter
  2. import (
  3. "fmt"
  4. "unicode"
  5. )
  6. // ReadObject read one field from object.
  7. // If object ended, returns empty string.
  8. // Otherwise, returns the field name.
  9. func (iter *Iterator) ReadObject() (ret string) {
  10. c := iter.nextToken()
  11. switch c {
  12. case 'n':
  13. iter.skipThreeBytes('u', 'l', 'l')
  14. return "" // null
  15. case '{':
  16. c = iter.nextToken()
  17. if c == '"' {
  18. iter.unreadByte()
  19. field := iter.ReadString()
  20. c = iter.nextToken()
  21. if c != ':' {
  22. iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
  23. }
  24. return field
  25. }
  26. if c == '}' {
  27. return "" // end of object
  28. }
  29. iter.ReportError("ReadObject", `expect " after {, but found `+string([]byte{c}))
  30. return
  31. case ',':
  32. field := iter.ReadString()
  33. c = iter.nextToken()
  34. if c != ':' {
  35. iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
  36. }
  37. return field
  38. case '}':
  39. return "" // end of object
  40. default:
  41. iter.ReportError("ReadObject", fmt.Sprintf(`expect { or , or } or n, but found %s`, string([]byte{c})))
  42. return
  43. }
  44. }
  45. // CaseInsensitive
  46. func (iter *Iterator) readFieldHash() int64 {
  47. hash := int64(0x811c9dc5)
  48. c := iter.nextToken()
  49. if c != '"' {
  50. iter.ReportError("readFieldHash", `expect ", but found `+string([]byte{c}))
  51. return 0
  52. }
  53. for {
  54. for i := iter.head; i < iter.tail; i++ {
  55. // require ascii string and no escape
  56. b := iter.buf[i]
  57. if b == '\\' {
  58. iter.head = i
  59. for _, b := range iter.readStringSlowPath() {
  60. if 'A' <= b && b <= 'Z' && !iter.cfg.caseSensitive {
  61. b += 'a' - 'A'
  62. }
  63. hash ^= int64(b)
  64. hash *= 0x1000193
  65. }
  66. c = iter.nextToken()
  67. if c != ':' {
  68. iter.ReportError("readFieldHash", `expect :, but found `+string([]byte{c}))
  69. return 0
  70. }
  71. return hash
  72. }
  73. if b == '"' {
  74. iter.head = i + 1
  75. c = iter.nextToken()
  76. if c != ':' {
  77. iter.ReportError("readFieldHash", `expect :, but found `+string([]byte{c}))
  78. return 0
  79. }
  80. return hash
  81. }
  82. if 'A' <= b && b <= 'Z' && !iter.cfg.caseSensitive {
  83. b += 'a' - 'A'
  84. }
  85. hash ^= int64(b)
  86. hash *= 0x1000193
  87. }
  88. if !iter.loadMore() {
  89. iter.ReportError("readFieldHash", `incomplete field name`)
  90. return 0
  91. }
  92. }
  93. }
  94. func calcHash(str string, caseSensitive bool) int64 {
  95. hash := int64(0x811c9dc5)
  96. for _, b := range str {
  97. if caseSensitive {
  98. hash ^= int64(b)
  99. } else {
  100. hash ^= int64(unicode.ToLower(b))
  101. }
  102. hash *= 0x1000193
  103. }
  104. return int64(hash)
  105. }
  106. // ReadObjectCB read object with callback, the key is ascii only and field name not copied
  107. func (iter *Iterator) ReadObjectCB(callback func(*Iterator, string) bool) bool {
  108. c := iter.nextToken()
  109. var field string
  110. if c == '{' {
  111. c = iter.nextToken()
  112. if c == '"' {
  113. iter.unreadByte()
  114. field = iter.ReadString()
  115. c = iter.nextToken()
  116. if c != ':' {
  117. iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
  118. }
  119. if !callback(iter, field) {
  120. return false
  121. }
  122. c = iter.nextToken()
  123. for c == ',' {
  124. field = iter.ReadString()
  125. c = iter.nextToken()
  126. if c != ':' {
  127. iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
  128. }
  129. if !callback(iter, field) {
  130. return false
  131. }
  132. c = iter.nextToken()
  133. }
  134. if c != '}' {
  135. iter.ReportError("ReadObjectCB", `object not ended with }`)
  136. return false
  137. }
  138. return true
  139. }
  140. if c == '}' {
  141. return true
  142. }
  143. iter.ReportError("ReadObjectCB", `expect " after }, but found `+string([]byte{c}))
  144. return false
  145. }
  146. if c == 'n' {
  147. iter.skipThreeBytes('u', 'l', 'l')
  148. return true // null
  149. }
  150. iter.ReportError("ReadObjectCB", `expect { or n, but found `+string([]byte{c}))
  151. return false
  152. }
  153. // ReadMapCB read map with callback, the key can be any string
  154. func (iter *Iterator) ReadMapCB(callback func(*Iterator, string) bool) bool {
  155. c := iter.nextToken()
  156. if c == '{' {
  157. c = iter.nextToken()
  158. if c == '"' {
  159. iter.unreadByte()
  160. field := iter.ReadString()
  161. if iter.nextToken() != ':' {
  162. iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
  163. return false
  164. }
  165. if !callback(iter, field) {
  166. return false
  167. }
  168. c = iter.nextToken()
  169. for c == ',' {
  170. field = iter.ReadString()
  171. if iter.nextToken() != ':' {
  172. iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
  173. return false
  174. }
  175. if !callback(iter, field) {
  176. return false
  177. }
  178. c = iter.nextToken()
  179. }
  180. if c != '}' {
  181. iter.ReportError("ReadMapCB", `object not ended with }`)
  182. return false
  183. }
  184. return true
  185. }
  186. if c == '}' {
  187. return true
  188. }
  189. iter.ReportError("ReadMapCB", `expect " after }, but found `+string([]byte{c}))
  190. return false
  191. }
  192. if c == 'n' {
  193. iter.skipThreeBytes('u', 'l', 'l')
  194. return true // null
  195. }
  196. iter.ReportError("ReadMapCB", `expect { or n, but found `+string([]byte{c}))
  197. return false
  198. }
  199. func (iter *Iterator) readObjectStart() bool {
  200. c := iter.nextToken()
  201. if c == '{' {
  202. c = iter.nextToken()
  203. if c == '}' {
  204. return false
  205. }
  206. iter.unreadByte()
  207. return true
  208. } else if c == 'n' {
  209. iter.skipThreeBytes('u', 'l', 'l')
  210. return false
  211. }
  212. iter.ReportError("readObjectStart", "expect { or n, but found "+string([]byte{c}))
  213. return false
  214. }
  215. func (iter *Iterator) readObjectFieldAsBytes() (ret []byte) {
  216. str := iter.ReadStringAsSlice()
  217. if iter.skipWhitespacesWithoutLoadMore() {
  218. if ret == nil {
  219. ret = make([]byte, len(str))
  220. copy(ret, str)
  221. }
  222. if !iter.loadMore() {
  223. return
  224. }
  225. }
  226. if iter.buf[iter.head] != ':' {
  227. iter.ReportError("readObjectFieldAsBytes", "expect : after object field, but found "+string([]byte{iter.buf[iter.head]}))
  228. return
  229. }
  230. iter.head++
  231. if iter.skipWhitespacesWithoutLoadMore() {
  232. if ret == nil {
  233. ret = make([]byte, len(str))
  234. copy(ret, str)
  235. }
  236. if !iter.loadMore() {
  237. return
  238. }
  239. }
  240. if ret == nil {
  241. return str
  242. }
  243. return ret
  244. }