/src/libyaml/writer.c

https://code.google.com/ · C · 141 lines · 88 code · 33 blank · 20 comment · 22 complexity · ede6fecf08c77109b81f1054d4224a91 MD5 · raw file

  1. #include "yaml_private.h"
  2. /*
  3. * Declarations.
  4. */
  5. static int
  6. yaml_emitter_set_writer_error(yaml_emitter_t *emitter, const char *problem);
  7. YAML_DECLARE(int)
  8. yaml_emitter_flush(yaml_emitter_t *emitter);
  9. /*
  10. * Set the writer error and return 0.
  11. */
  12. static int
  13. yaml_emitter_set_writer_error(yaml_emitter_t *emitter, const char *problem)
  14. {
  15. emitter->error = YAML_WRITER_ERROR;
  16. emitter->problem = problem;
  17. return 0;
  18. }
  19. /*
  20. * Flush the output buffer.
  21. */
  22. YAML_DECLARE(int)
  23. yaml_emitter_flush(yaml_emitter_t *emitter)
  24. {
  25. int low, high;
  26. assert(emitter); /* Non-NULL emitter object is expected. */
  27. assert(emitter->write_handler); /* Write handler must be set. */
  28. assert(emitter->encoding); /* Output encoding must be set. */
  29. emitter->buffer.last = emitter->buffer.pointer;
  30. emitter->buffer.pointer = emitter->buffer.start;
  31. /* Check if the buffer is empty. */
  32. if (emitter->buffer.start == emitter->buffer.last) {
  33. return 1;
  34. }
  35. /* If the output encoding is UTF-8, we don't need to recode the buffer. */
  36. if (emitter->encoding == YAML_UTF8_ENCODING)
  37. {
  38. if (emitter->write_handler(emitter->write_handler_data,
  39. emitter->buffer.start,
  40. emitter->buffer.last - emitter->buffer.start)) {
  41. emitter->buffer.last = emitter->buffer.start;
  42. emitter->buffer.pointer = emitter->buffer.start;
  43. return 1;
  44. }
  45. else {
  46. return yaml_emitter_set_writer_error(emitter, "write error");
  47. }
  48. }
  49. /* Recode the buffer into the raw buffer. */
  50. low = (emitter->encoding == YAML_UTF16LE_ENCODING ? 0 : 1);
  51. high = (emitter->encoding == YAML_UTF16LE_ENCODING ? 1 : 0);
  52. while (emitter->buffer.pointer != emitter->buffer.last)
  53. {
  54. unsigned char octet;
  55. unsigned int width;
  56. unsigned int value;
  57. size_t k;
  58. /*
  59. * See the "reader.c" code for more details on UTF-8 encoding. Note
  60. * that we assume that the buffer contains a valid UTF-8 sequence.
  61. */
  62. /* Read the next UTF-8 character. */
  63. octet = emitter->buffer.pointer[0];
  64. width = (octet & 0x80) == 0x00 ? 1 :
  65. (octet & 0xE0) == 0xC0 ? 2 :
  66. (octet & 0xF0) == 0xE0 ? 3 :
  67. (octet & 0xF8) == 0xF0 ? 4 : 0;
  68. value = (octet & 0x80) == 0x00 ? octet & 0x7F :
  69. (octet & 0xE0) == 0xC0 ? octet & 0x1F :
  70. (octet & 0xF0) == 0xE0 ? octet & 0x0F :
  71. (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
  72. for (k = 1; k < width; k ++) {
  73. octet = emitter->buffer.pointer[k];
  74. value = (value << 6) + (octet & 0x3F);
  75. }
  76. emitter->buffer.pointer += width;
  77. /* Write the character. */
  78. if (value < 0x10000)
  79. {
  80. emitter->raw_buffer.last[high] = value >> 8;
  81. emitter->raw_buffer.last[low] = value & 0xFF;
  82. emitter->raw_buffer.last += 2;
  83. }
  84. else
  85. {
  86. /* Write the character using a surrogate pair (check "reader.c"). */
  87. value -= 0x10000;
  88. emitter->raw_buffer.last[high] = 0xD8 + (value >> 18);
  89. emitter->raw_buffer.last[low] = (value >> 10) & 0xFF;
  90. emitter->raw_buffer.last[high+2] = 0xDC + ((value >> 8) & 0xFF);
  91. emitter->raw_buffer.last[low+2] = value & 0xFF;
  92. emitter->raw_buffer.last += 4;
  93. }
  94. }
  95. /* Write the raw buffer. */
  96. if (emitter->write_handler(emitter->write_handler_data,
  97. emitter->raw_buffer.start,
  98. emitter->raw_buffer.last - emitter->raw_buffer.start)) {
  99. emitter->buffer.last = emitter->buffer.start;
  100. emitter->buffer.pointer = emitter->buffer.start;
  101. emitter->raw_buffer.last = emitter->raw_buffer.start;
  102. emitter->raw_buffer.pointer = emitter->raw_buffer.start;
  103. return 1;
  104. }
  105. else {
  106. return yaml_emitter_set_writer_error(emitter, "write error");
  107. }
  108. }