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Beego/vendor/gopkg.in/yaml.v2/emitterc.go
2018-07-31 21:18:07 +08:00

1686 lines
44 KiB
Go

package yaml
import (
"bytes"
"fmt"
)
// Flush the buffer if needed.
func flush(emitter *yaml_emitter_t) bool {
if emitter.buffer_pos+5 >= len(emitter.buffer) {
return yaml_emitter_flush(emitter)
}
return true
}
// Put a character to the output buffer.
func put(emitter *yaml_emitter_t, value byte) bool {
if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
return false
}
emitter.buffer[emitter.buffer_pos] = value
emitter.buffer_pos++
emitter.column++
return true
}
// Put a line break to the output buffer.
func put_break(emitter *yaml_emitter_t) bool {
if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
return false
}
switch emitter.line_break {
case yaml_CR_BREAK:
emitter.buffer[emitter.buffer_pos] = '\r'
emitter.buffer_pos += 1
case yaml_LN_BREAK:
emitter.buffer[emitter.buffer_pos] = '\n'
emitter.buffer_pos += 1
case yaml_CRLN_BREAK:
emitter.buffer[emitter.buffer_pos+0] = '\r'
emitter.buffer[emitter.buffer_pos+1] = '\n'
emitter.buffer_pos += 2
default:
panic("unknown line break setting")
}
emitter.column = 0
emitter.line++
return true
}
// Copy a character from a string into buffer.
func write(emitter *yaml_emitter_t, s []byte, i *int) bool {
if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
return false
}
p := emitter.buffer_pos
w := width(s[*i])
switch w {
case 4:
emitter.buffer[p+3] = s[*i+3]
fallthrough
case 3:
emitter.buffer[p+2] = s[*i+2]
fallthrough
case 2:
emitter.buffer[p+1] = s[*i+1]
fallthrough
case 1:
emitter.buffer[p+0] = s[*i+0]
default:
panic("unknown character width")
}
emitter.column++
emitter.buffer_pos += w
*i += w
return true
}
// Write a whole string into buffer.
func write_all(emitter *yaml_emitter_t, s []byte) bool {
for i := 0; i < len(s); {
if !write(emitter, s, &i) {
return false
}
}
return true
}
// Copy a line break character from a string into buffer.
func write_break(emitter *yaml_emitter_t, s []byte, i *int) bool {
if s[*i] == '\n' {
if !put_break(emitter) {
return false
}
*i++
} else {
if !write(emitter, s, i) {
return false
}
emitter.column = 0
emitter.line++
}
return true
}
// Set an emitter error and return false.
func yaml_emitter_set_emitter_error(emitter *yaml_emitter_t, problem string) bool {
emitter.error = yaml_EMITTER_ERROR
emitter.problem = problem
return false
}
// Emit an event.
func yaml_emitter_emit(emitter *yaml_emitter_t, event *yaml_event_t) bool {
emitter.events = append(emitter.events, *event)
for !yaml_emitter_need_more_events(emitter) {
event := &emitter.events[emitter.events_head]
if !yaml_emitter_analyze_event(emitter, event) {
return false
}
if !yaml_emitter_state_machine(emitter, event) {
return false
}
yaml_event_delete(event)
emitter.events_head++
}
return true
}
// Check if we need to accumulate more events before emitting.
//
// We accumulate extra
// - 1 event for DOCUMENT-START
// - 2 events for SEQUENCE-START
// - 3 events for MAPPING-START
//
func yaml_emitter_need_more_events(emitter *yaml_emitter_t) bool {
if emitter.events_head == len(emitter.events) {
return true
}
var accumulate int
switch emitter.events[emitter.events_head].typ {
case yaml_DOCUMENT_START_EVENT:
accumulate = 1
break
case yaml_SEQUENCE_START_EVENT:
accumulate = 2
break
case yaml_MAPPING_START_EVENT:
accumulate = 3
break
default:
return false
}
if len(emitter.events)-emitter.events_head > accumulate {
return false
}
var level int
for i := emitter.events_head; i < len(emitter.events); i++ {
switch emitter.events[i].typ {
case yaml_STREAM_START_EVENT, yaml_DOCUMENT_START_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT:
level++
case yaml_STREAM_END_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_END_EVENT, yaml_MAPPING_END_EVENT:
level--
}
if level == 0 {
return false
}
}
return true
}
// Append a directive to the directives stack.
func yaml_emitter_append_tag_directive(emitter *yaml_emitter_t, value *yaml_tag_directive_t, allow_duplicates bool) bool {
for i := 0; i < len(emitter.tag_directives); i++ {
if bytes.Equal(value.handle, emitter.tag_directives[i].handle) {
if allow_duplicates {
return true
}
return yaml_emitter_set_emitter_error(emitter, "duplicate %TAG directive")
}
}
// [Go] Do we actually need to copy this given garbage collection
// and the lack of deallocating destructors?
tag_copy := yaml_tag_directive_t{
handle: make([]byte, len(value.handle)),
prefix: make([]byte, len(value.prefix)),
}
copy(tag_copy.handle, value.handle)
copy(tag_copy.prefix, value.prefix)
emitter.tag_directives = append(emitter.tag_directives, tag_copy)
return true
}
// Increase the indentation level.
func yaml_emitter_increase_indent(emitter *yaml_emitter_t, flow, indentless bool) bool {
emitter.indents = append(emitter.indents, emitter.indent)
if emitter.indent < 0 {
if flow {
emitter.indent = emitter.best_indent
} else {
emitter.indent = 0
}
} else if !indentless {
emitter.indent += emitter.best_indent
}
return true
}
// State dispatcher.
func yaml_emitter_state_machine(emitter *yaml_emitter_t, event *yaml_event_t) bool {
switch emitter.state {
default:
case yaml_EMIT_STREAM_START_STATE:
return yaml_emitter_emit_stream_start(emitter, event)
case yaml_EMIT_FIRST_DOCUMENT_START_STATE:
return yaml_emitter_emit_document_start(emitter, event, true)
case yaml_EMIT_DOCUMENT_START_STATE:
return yaml_emitter_emit_document_start(emitter, event, false)
case yaml_EMIT_DOCUMENT_CONTENT_STATE:
return yaml_emitter_emit_document_content(emitter, event)
case yaml_EMIT_DOCUMENT_END_STATE:
return yaml_emitter_emit_document_end(emitter, event)
case yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE:
return yaml_emitter_emit_flow_sequence_item(emitter, event, true)
case yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE:
return yaml_emitter_emit_flow_sequence_item(emitter, event, false)
case yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE:
return yaml_emitter_emit_flow_mapping_key(emitter, event, true)
case yaml_EMIT_FLOW_MAPPING_KEY_STATE:
return yaml_emitter_emit_flow_mapping_key(emitter, event, false)
case yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE:
return yaml_emitter_emit_flow_mapping_value(emitter, event, true)
case yaml_EMIT_FLOW_MAPPING_VALUE_STATE:
return yaml_emitter_emit_flow_mapping_value(emitter, event, false)
case yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE:
return yaml_emitter_emit_block_sequence_item(emitter, event, true)
case yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE:
return yaml_emitter_emit_block_sequence_item(emitter, event, false)
case yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE:
return yaml_emitter_emit_block_mapping_key(emitter, event, true)
case yaml_EMIT_BLOCK_MAPPING_KEY_STATE:
return yaml_emitter_emit_block_mapping_key(emitter, event, false)
case yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE:
return yaml_emitter_emit_block_mapping_value(emitter, event, true)
case yaml_EMIT_BLOCK_MAPPING_VALUE_STATE:
return yaml_emitter_emit_block_mapping_value(emitter, event, false)
case yaml_EMIT_END_STATE:
return yaml_emitter_set_emitter_error(emitter, "expected nothing after STREAM-END")
}
panic("invalid emitter state")
}
// Expect STREAM-START.
func yaml_emitter_emit_stream_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if event.typ != yaml_STREAM_START_EVENT {
return yaml_emitter_set_emitter_error(emitter, "expected STREAM-START")
}
if emitter.encoding == yaml_ANY_ENCODING {
emitter.encoding = event.encoding
if emitter.encoding == yaml_ANY_ENCODING {
emitter.encoding = yaml_UTF8_ENCODING
}
}
if emitter.best_indent < 2 || emitter.best_indent > 9 {
emitter.best_indent = 2
}
if emitter.best_width >= 0 && emitter.best_width <= emitter.best_indent*2 {
emitter.best_width = 80
}
if emitter.best_width < 0 {
emitter.best_width = 1<<31 - 1
}
if emitter.line_break == yaml_ANY_BREAK {
emitter.line_break = yaml_LN_BREAK
}
emitter.indent = -1
emitter.line = 0
emitter.column = 0
emitter.whitespace = true
emitter.indention = true
if emitter.encoding != yaml_UTF8_ENCODING {
if !yaml_emitter_write_bom(emitter) {
return false
}
}
emitter.state = yaml_EMIT_FIRST_DOCUMENT_START_STATE
return true
}
// Expect DOCUMENT-START or STREAM-END.
func yaml_emitter_emit_document_start(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
if event.typ == yaml_DOCUMENT_START_EVENT {
if event.version_directive != nil {
if !yaml_emitter_analyze_version_directive(emitter, event.version_directive) {
return false
}
}
for i := 0; i < len(event.tag_directives); i++ {
tag_directive := &event.tag_directives[i]
if !yaml_emitter_analyze_tag_directive(emitter, tag_directive) {
return false
}
if !yaml_emitter_append_tag_directive(emitter, tag_directive, false) {
return false
}
}
for i := 0; i < len(default_tag_directives); i++ {
tag_directive := &default_tag_directives[i]
if !yaml_emitter_append_tag_directive(emitter, tag_directive, true) {
return false
}
}
implicit := event.implicit
if !first || emitter.canonical {
implicit = false
}
if emitter.open_ended && (event.version_directive != nil || len(event.tag_directives) > 0) {
if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if event.version_directive != nil {
implicit = false
if !yaml_emitter_write_indicator(emitter, []byte("%YAML"), true, false, false) {
return false
}
if !yaml_emitter_write_indicator(emitter, []byte("1.1"), true, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if len(event.tag_directives) > 0 {
implicit = false
for i := 0; i < len(event.tag_directives); i++ {
tag_directive := &event.tag_directives[i]
if !yaml_emitter_write_indicator(emitter, []byte("%TAG"), true, false, false) {
return false
}
if !yaml_emitter_write_tag_handle(emitter, tag_directive.handle) {
return false
}
if !yaml_emitter_write_tag_content(emitter, tag_directive.prefix, true) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
}
if yaml_emitter_check_empty_document(emitter) {
implicit = false
}
if !implicit {
if !yaml_emitter_write_indent(emitter) {
return false
}
if !yaml_emitter_write_indicator(emitter, []byte("---"), true, false, false) {
return false
}
if emitter.canonical {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
}
emitter.state = yaml_EMIT_DOCUMENT_CONTENT_STATE
return true
}
if event.typ == yaml_STREAM_END_EVENT {
if emitter.open_ended {
if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !yaml_emitter_flush(emitter) {
return false
}
emitter.state = yaml_EMIT_END_STATE
return true
}
return yaml_emitter_set_emitter_error(emitter, "expected DOCUMENT-START or STREAM-END")
}
// Expect the root node.
func yaml_emitter_emit_document_content(emitter *yaml_emitter_t, event *yaml_event_t) bool {
emitter.states = append(emitter.states, yaml_EMIT_DOCUMENT_END_STATE)
return yaml_emitter_emit_node(emitter, event, true, false, false, false)
}
// Expect DOCUMENT-END.
func yaml_emitter_emit_document_end(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if event.typ != yaml_DOCUMENT_END_EVENT {
return yaml_emitter_set_emitter_error(emitter, "expected DOCUMENT-END")
}
if !yaml_emitter_write_indent(emitter) {
return false
}
if !event.implicit {
// [Go] Allocate the slice elsewhere.
if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !yaml_emitter_flush(emitter) {
return false
}
emitter.state = yaml_EMIT_DOCUMENT_START_STATE
emitter.tag_directives = emitter.tag_directives[:0]
return true
}
// Expect a flow item node.
func yaml_emitter_emit_flow_sequence_item(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
if first {
if !yaml_emitter_write_indicator(emitter, []byte{'['}, true, true, false) {
return false
}
if !yaml_emitter_increase_indent(emitter, true, false) {
return false
}
emitter.flow_level++
}
if event.typ == yaml_SEQUENCE_END_EVENT {
emitter.flow_level--
emitter.indent = emitter.indents[len(emitter.indents)-1]
emitter.indents = emitter.indents[:len(emitter.indents)-1]
if emitter.canonical && !first {
if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !yaml_emitter_write_indicator(emitter, []byte{']'}, false, false, false) {
return false
}
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
if !first {
if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
return false
}
}
if emitter.canonical || emitter.column > emitter.best_width {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
emitter.states = append(emitter.states, yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE)
return yaml_emitter_emit_node(emitter, event, false, true, false, false)
}
// Expect a flow key node.
func yaml_emitter_emit_flow_mapping_key(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
if first {
if !yaml_emitter_write_indicator(emitter, []byte{'{'}, true, true, false) {
return false
}
if !yaml_emitter_increase_indent(emitter, true, false) {
return false
}
emitter.flow_level++
}
if event.typ == yaml_MAPPING_END_EVENT {
emitter.flow_level--
emitter.indent = emitter.indents[len(emitter.indents)-1]
emitter.indents = emitter.indents[:len(emitter.indents)-1]
if emitter.canonical && !first {
if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
return false
}
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !yaml_emitter_write_indicator(emitter, []byte{'}'}, false, false, false) {
return false
}
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
if !first {
if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
return false
}
}
if emitter.canonical || emitter.column > emitter.best_width {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !emitter.canonical && yaml_emitter_check_simple_key(emitter) {
emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, true)
}
if !yaml_emitter_write_indicator(emitter, []byte{'?'}, true, false, false) {
return false
}
emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_VALUE_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, false)
}
// Expect a flow value node.
func yaml_emitter_emit_flow_mapping_value(emitter *yaml_emitter_t, event *yaml_event_t, simple bool) bool {
if simple {
if !yaml_emitter_write_indicator(emitter, []byte{':'}, false, false, false) {
return false
}
} else {
if emitter.canonical || emitter.column > emitter.best_width {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !yaml_emitter_write_indicator(emitter, []byte{':'}, true, false, false) {
return false
}
}
emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_KEY_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, false)
}
// Expect a block item node.
func yaml_emitter_emit_block_sequence_item(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
if first {
if !yaml_emitter_increase_indent(emitter, false, emitter.mapping_context && !emitter.indention) {
return false
}
}
if event.typ == yaml_SEQUENCE_END_EVENT {
emitter.indent = emitter.indents[len(emitter.indents)-1]
emitter.indents = emitter.indents[:len(emitter.indents)-1]
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
if !yaml_emitter_write_indent(emitter) {
return false
}
if !yaml_emitter_write_indicator(emitter, []byte{'-'}, true, false, true) {
return false
}
emitter.states = append(emitter.states, yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE)
return yaml_emitter_emit_node(emitter, event, false, true, false, false)
}
// Expect a block key node.
func yaml_emitter_emit_block_mapping_key(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
if first {
if !yaml_emitter_increase_indent(emitter, false, false) {
return false
}
}
if event.typ == yaml_MAPPING_END_EVENT {
emitter.indent = emitter.indents[len(emitter.indents)-1]
emitter.indents = emitter.indents[:len(emitter.indents)-1]
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
if !yaml_emitter_write_indent(emitter) {
return false
}
if yaml_emitter_check_simple_key(emitter) {
emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, true)
}
if !yaml_emitter_write_indicator(emitter, []byte{'?'}, true, false, true) {
return false
}
emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_VALUE_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, false)
}
// Expect a block value node.
func yaml_emitter_emit_block_mapping_value(emitter *yaml_emitter_t, event *yaml_event_t, simple bool) bool {
if simple {
if !yaml_emitter_write_indicator(emitter, []byte{':'}, false, false, false) {
return false
}
} else {
if !yaml_emitter_write_indent(emitter) {
return false
}
if !yaml_emitter_write_indicator(emitter, []byte{':'}, true, false, true) {
return false
}
}
emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_KEY_STATE)
return yaml_emitter_emit_node(emitter, event, false, false, true, false)
}
// Expect a node.
func yaml_emitter_emit_node(emitter *yaml_emitter_t, event *yaml_event_t,
root bool, sequence bool, mapping bool, simple_key bool) bool {
emitter.root_context = root
emitter.sequence_context = sequence
emitter.mapping_context = mapping
emitter.simple_key_context = simple_key
switch event.typ {
case yaml_ALIAS_EVENT:
return yaml_emitter_emit_alias(emitter, event)
case yaml_SCALAR_EVENT:
return yaml_emitter_emit_scalar(emitter, event)
case yaml_SEQUENCE_START_EVENT:
return yaml_emitter_emit_sequence_start(emitter, event)
case yaml_MAPPING_START_EVENT:
return yaml_emitter_emit_mapping_start(emitter, event)
default:
return yaml_emitter_set_emitter_error(emitter,
fmt.Sprintf("expected SCALAR, SEQUENCE-START, MAPPING-START, or ALIAS, but got %v", event.typ))
}
}
// Expect ALIAS.
func yaml_emitter_emit_alias(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if !yaml_emitter_process_anchor(emitter) {
return false
}
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
// Expect SCALAR.
func yaml_emitter_emit_scalar(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if !yaml_emitter_select_scalar_style(emitter, event) {
return false
}
if !yaml_emitter_process_anchor(emitter) {
return false
}
if !yaml_emitter_process_tag(emitter) {
return false
}
if !yaml_emitter_increase_indent(emitter, true, false) {
return false
}
if !yaml_emitter_process_scalar(emitter) {
return false
}
emitter.indent = emitter.indents[len(emitter.indents)-1]
emitter.indents = emitter.indents[:len(emitter.indents)-1]
emitter.state = emitter.states[len(emitter.states)-1]
emitter.states = emitter.states[:len(emitter.states)-1]
return true
}
// Expect SEQUENCE-START.
func yaml_emitter_emit_sequence_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if !yaml_emitter_process_anchor(emitter) {
return false
}
if !yaml_emitter_process_tag(emitter) {
return false
}
if emitter.flow_level > 0 || emitter.canonical || event.sequence_style() == yaml_FLOW_SEQUENCE_STYLE ||
yaml_emitter_check_empty_sequence(emitter) {
emitter.state = yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE
} else {
emitter.state = yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE
}
return true
}
// Expect MAPPING-START.
func yaml_emitter_emit_mapping_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
if !yaml_emitter_process_anchor(emitter) {
return false
}
if !yaml_emitter_process_tag(emitter) {
return false
}
if emitter.flow_level > 0 || emitter.canonical || event.mapping_style() == yaml_FLOW_MAPPING_STYLE ||
yaml_emitter_check_empty_mapping(emitter) {
emitter.state = yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE
} else {
emitter.state = yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE
}
return true
}
// Check if the document content is an empty scalar.
func yaml_emitter_check_empty_document(emitter *yaml_emitter_t) bool {
return false // [Go] Huh?
}
// Check if the next events represent an empty sequence.
func yaml_emitter_check_empty_sequence(emitter *yaml_emitter_t) bool {
if len(emitter.events)-emitter.events_head < 2 {
return false
}
return emitter.events[emitter.events_head].typ == yaml_SEQUENCE_START_EVENT &&
emitter.events[emitter.events_head+1].typ == yaml_SEQUENCE_END_EVENT
}
// Check if the next events represent an empty mapping.
func yaml_emitter_check_empty_mapping(emitter *yaml_emitter_t) bool {
if len(emitter.events)-emitter.events_head < 2 {
return false
}
return emitter.events[emitter.events_head].typ == yaml_MAPPING_START_EVENT &&
emitter.events[emitter.events_head+1].typ == yaml_MAPPING_END_EVENT
}
// Check if the next node can be expressed as a simple key.
func yaml_emitter_check_simple_key(emitter *yaml_emitter_t) bool {
length := 0
switch emitter.events[emitter.events_head].typ {
case yaml_ALIAS_EVENT:
length += len(emitter.anchor_data.anchor)
case yaml_SCALAR_EVENT:
if emitter.scalar_data.multiline {
return false
}
length += len(emitter.anchor_data.anchor) +
len(emitter.tag_data.handle) +
len(emitter.tag_data.suffix) +
len(emitter.scalar_data.value)
case yaml_SEQUENCE_START_EVENT:
if !yaml_emitter_check_empty_sequence(emitter) {
return false
}
length += len(emitter.anchor_data.anchor) +
len(emitter.tag_data.handle) +
len(emitter.tag_data.suffix)
case yaml_MAPPING_START_EVENT:
if !yaml_emitter_check_empty_mapping(emitter) {
return false
}
length += len(emitter.anchor_data.anchor) +
len(emitter.tag_data.handle) +
len(emitter.tag_data.suffix)
default:
return false
}
return length <= 128
}
// Determine an acceptable scalar style.
func yaml_emitter_select_scalar_style(emitter *yaml_emitter_t, event *yaml_event_t) bool {
no_tag := len(emitter.tag_data.handle) == 0 && len(emitter.tag_data.suffix) == 0
if no_tag && !event.implicit && !event.quoted_implicit {
return yaml_emitter_set_emitter_error(emitter, "neither tag nor implicit flags are specified")
}
style := event.scalar_style()
if style == yaml_ANY_SCALAR_STYLE {
style = yaml_PLAIN_SCALAR_STYLE
}
if emitter.canonical {
style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
}
if emitter.simple_key_context && emitter.scalar_data.multiline {
style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
}
if style == yaml_PLAIN_SCALAR_STYLE {
if emitter.flow_level > 0 && !emitter.scalar_data.flow_plain_allowed ||
emitter.flow_level == 0 && !emitter.scalar_data.block_plain_allowed {
style = yaml_SINGLE_QUOTED_SCALAR_STYLE
}
if len(emitter.scalar_data.value) == 0 && (emitter.flow_level > 0 || emitter.simple_key_context) {
style = yaml_SINGLE_QUOTED_SCALAR_STYLE
}
if no_tag && !event.implicit {
style = yaml_SINGLE_QUOTED_SCALAR_STYLE
}
}
if style == yaml_SINGLE_QUOTED_SCALAR_STYLE {
if !emitter.scalar_data.single_quoted_allowed {
style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
}
}
if style == yaml_LITERAL_SCALAR_STYLE || style == yaml_FOLDED_SCALAR_STYLE {
if !emitter.scalar_data.block_allowed || emitter.flow_level > 0 || emitter.simple_key_context {
style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
}
}
if no_tag && !event.quoted_implicit && style != yaml_PLAIN_SCALAR_STYLE {
emitter.tag_data.handle = []byte{'!'}
}
emitter.scalar_data.style = style
return true
}
// Write an anchor.
func yaml_emitter_process_anchor(emitter *yaml_emitter_t) bool {
if emitter.anchor_data.anchor == nil {
return true
}
c := []byte{'&'}
if emitter.anchor_data.alias {
c[0] = '*'
}
if !yaml_emitter_write_indicator(emitter, c, true, false, false) {
return false
}
return yaml_emitter_write_anchor(emitter, emitter.anchor_data.anchor)
}
// Write a tag.
func yaml_emitter_process_tag(emitter *yaml_emitter_t) bool {
if len(emitter.tag_data.handle) == 0 && len(emitter.tag_data.suffix) == 0 {
return true
}
if len(emitter.tag_data.handle) > 0 {
if !yaml_emitter_write_tag_handle(emitter, emitter.tag_data.handle) {
return false
}
if len(emitter.tag_data.suffix) > 0 {
if !yaml_emitter_write_tag_content(emitter, emitter.tag_data.suffix, false) {
return false
}
}
} else {
// [Go] Allocate these slices elsewhere.
if !yaml_emitter_write_indicator(emitter, []byte("!<"), true, false, false) {
return false
}
if !yaml_emitter_write_tag_content(emitter, emitter.tag_data.suffix, false) {
return false
}
if !yaml_emitter_write_indicator(emitter, []byte{'>'}, false, false, false) {
return false
}
}
return true
}
// Write a scalar.
func yaml_emitter_process_scalar(emitter *yaml_emitter_t) bool {
switch emitter.scalar_data.style {
case yaml_PLAIN_SCALAR_STYLE:
return yaml_emitter_write_plain_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
case yaml_SINGLE_QUOTED_SCALAR_STYLE:
return yaml_emitter_write_single_quoted_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
case yaml_DOUBLE_QUOTED_SCALAR_STYLE:
return yaml_emitter_write_double_quoted_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
case yaml_LITERAL_SCALAR_STYLE:
return yaml_emitter_write_literal_scalar(emitter, emitter.scalar_data.value)
case yaml_FOLDED_SCALAR_STYLE:
return yaml_emitter_write_folded_scalar(emitter, emitter.scalar_data.value)
}
panic("unknown scalar style")
}
// Check if a %YAML directive is valid.
func yaml_emitter_analyze_version_directive(emitter *yaml_emitter_t, version_directive *yaml_version_directive_t) bool {
if version_directive.major != 1 || version_directive.minor != 1 {
return yaml_emitter_set_emitter_error(emitter, "incompatible %YAML directive")
}
return true
}
// Check if a %TAG directive is valid.
func yaml_emitter_analyze_tag_directive(emitter *yaml_emitter_t, tag_directive *yaml_tag_directive_t) bool {
handle := tag_directive.handle
prefix := tag_directive.prefix
if len(handle) == 0 {
return yaml_emitter_set_emitter_error(emitter, "tag handle must not be empty")
}
if handle[0] != '!' {
return yaml_emitter_set_emitter_error(emitter, "tag handle must start with '!'")
}
if handle[len(handle)-1] != '!' {
return yaml_emitter_set_emitter_error(emitter, "tag handle must end with '!'")
}
for i := 1; i < len(handle)-1; i += width(handle[i]) {
if !is_alpha(handle, i) {
return yaml_emitter_set_emitter_error(emitter, "tag handle must contain alphanumerical characters only")
}
}
if len(prefix) == 0 {
return yaml_emitter_set_emitter_error(emitter, "tag prefix must not be empty")
}
return true
}
// Check if an anchor is valid.
func yaml_emitter_analyze_anchor(emitter *yaml_emitter_t, anchor []byte, alias bool) bool {
if len(anchor) == 0 {
problem := "anchor value must not be empty"
if alias {
problem = "alias value must not be empty"
}
return yaml_emitter_set_emitter_error(emitter, problem)
}
for i := 0; i < len(anchor); i += width(anchor[i]) {
if !is_alpha(anchor, i) {
problem := "anchor value must contain alphanumerical characters only"
if alias {
problem = "alias value must contain alphanumerical characters only"
}
return yaml_emitter_set_emitter_error(emitter, problem)
}
}
emitter.anchor_data.anchor = anchor
emitter.anchor_data.alias = alias
return true
}
// Check if a tag is valid.
func yaml_emitter_analyze_tag(emitter *yaml_emitter_t, tag []byte) bool {
if len(tag) == 0 {
return yaml_emitter_set_emitter_error(emitter, "tag value must not be empty")
}
for i := 0; i < len(emitter.tag_directives); i++ {
tag_directive := &emitter.tag_directives[i]
if bytes.HasPrefix(tag, tag_directive.prefix) {
emitter.tag_data.handle = tag_directive.handle
emitter.tag_data.suffix = tag[len(tag_directive.prefix):]
return true
}
}
emitter.tag_data.suffix = tag
return true
}
// Check if a scalar is valid.
func yaml_emitter_analyze_scalar(emitter *yaml_emitter_t, value []byte) bool {
var (
block_indicators = false
flow_indicators = false
line_breaks = false
special_characters = false
leading_space = false
leading_break = false
trailing_space = false
trailing_break = false
break_space = false
space_break = false
preceded_by_whitespace = false
followed_by_whitespace = false
previous_space = false
previous_break = false
)
emitter.scalar_data.value = value
if len(value) == 0 {
emitter.scalar_data.multiline = false
emitter.scalar_data.flow_plain_allowed = false
emitter.scalar_data.block_plain_allowed = true
emitter.scalar_data.single_quoted_allowed = true
emitter.scalar_data.block_allowed = false
return true
}
if len(value) >= 3 && ((value[0] == '-' && value[1] == '-' && value[2] == '-') || (value[0] == '.' && value[1] == '.' && value[2] == '.')) {
block_indicators = true
flow_indicators = true
}
preceded_by_whitespace = true
for i, w := 0, 0; i < len(value); i += w {
w = width(value[i])
followed_by_whitespace = i+w >= len(value) || is_blank(value, i+w)
if i == 0 {
switch value[i] {
case '#', ',', '[', ']', '{', '}', '&', '*', '!', '|', '>', '\'', '"', '%', '@', '`':
flow_indicators = true
block_indicators = true
case '?', ':':
flow_indicators = true
if followed_by_whitespace {
block_indicators = true
}
case '-':
if followed_by_whitespace {
flow_indicators = true
block_indicators = true
}
}
} else {
switch value[i] {
case ',', '?', '[', ']', '{', '}':
flow_indicators = true
case ':':
flow_indicators = true
if followed_by_whitespace {
block_indicators = true
}
case '#':
if preceded_by_whitespace {
flow_indicators = true
block_indicators = true
}
}
}
if !is_printable(value, i) || !is_ascii(value, i) && !emitter.unicode {
special_characters = true
}
if is_space(value, i) {
if i == 0 {
leading_space = true
}
if i+width(value[i]) == len(value) {
trailing_space = true
}
if previous_break {
break_space = true
}
previous_space = true
previous_break = false
} else if is_break(value, i) {
line_breaks = true
if i == 0 {
leading_break = true
}
if i+width(value[i]) == len(value) {
trailing_break = true
}
if previous_space {
space_break = true
}
previous_space = false
previous_break = true
} else {
previous_space = false
previous_break = false
}
// [Go]: Why 'z'? Couldn't be the end of the string as that's the loop condition.
preceded_by_whitespace = is_blankz(value, i)
}
emitter.scalar_data.multiline = line_breaks
emitter.scalar_data.flow_plain_allowed = true
emitter.scalar_data.block_plain_allowed = true
emitter.scalar_data.single_quoted_allowed = true
emitter.scalar_data.block_allowed = true
if leading_space || leading_break || trailing_space || trailing_break {
emitter.scalar_data.flow_plain_allowed = false
emitter.scalar_data.block_plain_allowed = false
}
if trailing_space {
emitter.scalar_data.block_allowed = false
}
if break_space {
emitter.scalar_data.flow_plain_allowed = false
emitter.scalar_data.block_plain_allowed = false
emitter.scalar_data.single_quoted_allowed = false
}
if space_break || special_characters {
emitter.scalar_data.flow_plain_allowed = false
emitter.scalar_data.block_plain_allowed = false
emitter.scalar_data.single_quoted_allowed = false
emitter.scalar_data.block_allowed = false
}
if line_breaks {
emitter.scalar_data.flow_plain_allowed = false
emitter.scalar_data.block_plain_allowed = false
}
if flow_indicators {
emitter.scalar_data.flow_plain_allowed = false
}
if block_indicators {
emitter.scalar_data.block_plain_allowed = false
}
return true
}
// Check if the event data is valid.
func yaml_emitter_analyze_event(emitter *yaml_emitter_t, event *yaml_event_t) bool {
emitter.anchor_data.anchor = nil
emitter.tag_data.handle = nil
emitter.tag_data.suffix = nil
emitter.scalar_data.value = nil
switch event.typ {
case yaml_ALIAS_EVENT:
if !yaml_emitter_analyze_anchor(emitter, event.anchor, true) {
return false
}
case yaml_SCALAR_EVENT:
if len(event.anchor) > 0 {
if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
return false
}
}
if len(event.tag) > 0 && (emitter.canonical || (!event.implicit && !event.quoted_implicit)) {
if !yaml_emitter_analyze_tag(emitter, event.tag) {
return false
}
}
if !yaml_emitter_analyze_scalar(emitter, event.value) {
return false
}
case yaml_SEQUENCE_START_EVENT:
if len(event.anchor) > 0 {
if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
return false
}
}
if len(event.tag) > 0 && (emitter.canonical || !event.implicit) {
if !yaml_emitter_analyze_tag(emitter, event.tag) {
return false
}
}
case yaml_MAPPING_START_EVENT:
if len(event.anchor) > 0 {
if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
return false
}
}
if len(event.tag) > 0 && (emitter.canonical || !event.implicit) {
if !yaml_emitter_analyze_tag(emitter, event.tag) {
return false
}
}
}
return true
}
// Write the BOM character.
func yaml_emitter_write_bom(emitter *yaml_emitter_t) bool {
if !flush(emitter) {
return false
}
pos := emitter.buffer_pos
emitter.buffer[pos+0] = '\xEF'
emitter.buffer[pos+1] = '\xBB'
emitter.buffer[pos+2] = '\xBF'
emitter.buffer_pos += 3
return true
}
func yaml_emitter_write_indent(emitter *yaml_emitter_t) bool {
indent := emitter.indent
if indent < 0 {
indent = 0
}
if !emitter.indention || emitter.column > indent || (emitter.column == indent && !emitter.whitespace) {
if !put_break(emitter) {
return false
}
}
for emitter.column < indent {
if !put(emitter, ' ') {
return false
}
}
emitter.whitespace = true
emitter.indention = true
return true
}
func yaml_emitter_write_indicator(emitter *yaml_emitter_t, indicator []byte, need_whitespace, is_whitespace, is_indention bool) bool {
if need_whitespace && !emitter.whitespace {
if !put(emitter, ' ') {
return false
}
}
if !write_all(emitter, indicator) {
return false
}
emitter.whitespace = is_whitespace
emitter.indention = (emitter.indention && is_indention)
emitter.open_ended = false
return true
}
func yaml_emitter_write_anchor(emitter *yaml_emitter_t, value []byte) bool {
if !write_all(emitter, value) {
return false
}
emitter.whitespace = false
emitter.indention = false
return true
}
func yaml_emitter_write_tag_handle(emitter *yaml_emitter_t, value []byte) bool {
if !emitter.whitespace {
if !put(emitter, ' ') {
return false
}
}
if !write_all(emitter, value) {
return false
}
emitter.whitespace = false
emitter.indention = false
return true
}
func yaml_emitter_write_tag_content(emitter *yaml_emitter_t, value []byte, need_whitespace bool) bool {
if need_whitespace && !emitter.whitespace {
if !put(emitter, ' ') {
return false
}
}
for i := 0; i < len(value); {
var must_write bool
switch value[i] {
case ';', '/', '?', ':', '@', '&', '=', '+', '$', ',', '_', '.', '~', '*', '\'', '(', ')', '[', ']':
must_write = true
default:
must_write = is_alpha(value, i)
}
if must_write {
if !write(emitter, value, &i) {
return false
}
} else {
w := width(value[i])
for k := 0; k < w; k++ {
octet := value[i]
i++
if !put(emitter, '%') {
return false
}
c := octet >> 4
if c < 10 {
c += '0'
} else {
c += 'A' - 10
}
if !put(emitter, c) {
return false
}
c = octet & 0x0f
if c < 10 {
c += '0'
} else {
c += 'A' - 10
}
if !put(emitter, c) {
return false
}
}
}
}
emitter.whitespace = false
emitter.indention = false
return true
}
func yaml_emitter_write_plain_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
if !emitter.whitespace {
if !put(emitter, ' ') {
return false
}
}
spaces := false
breaks := false
for i := 0; i < len(value); {
if is_space(value, i) {
if allow_breaks && !spaces && emitter.column > emitter.best_width && !is_space(value, i+1) {
if !yaml_emitter_write_indent(emitter) {
return false
}
i += width(value[i])
} else {
if !write(emitter, value, &i) {
return false
}
}
spaces = true
} else if is_break(value, i) {
if !breaks && value[i] == '\n' {
if !put_break(emitter) {
return false
}
}
if !write_break(emitter, value, &i) {
return false
}
emitter.indention = true
breaks = true
} else {
if breaks {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !write(emitter, value, &i) {
return false
}
emitter.indention = false
spaces = false
breaks = false
}
}
emitter.whitespace = false
emitter.indention = false
if emitter.root_context {
emitter.open_ended = true
}
return true
}
func yaml_emitter_write_single_quoted_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
if !yaml_emitter_write_indicator(emitter, []byte{'\''}, true, false, false) {
return false
}
spaces := false
breaks := false
for i := 0; i < len(value); {
if is_space(value, i) {
if allow_breaks && !spaces && emitter.column > emitter.best_width && i > 0 && i < len(value)-1 && !is_space(value, i+1) {
if !yaml_emitter_write_indent(emitter) {
return false
}
i += width(value[i])
} else {
if !write(emitter, value, &i) {
return false
}
}
spaces = true
} else if is_break(value, i) {
if !breaks && value[i] == '\n' {
if !put_break(emitter) {
return false
}
}
if !write_break(emitter, value, &i) {
return false
}
emitter.indention = true
breaks = true
} else {
if breaks {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if value[i] == '\'' {
if !put(emitter, '\'') {
return false
}
}
if !write(emitter, value, &i) {
return false
}
emitter.indention = false
spaces = false
breaks = false
}
}
if !yaml_emitter_write_indicator(emitter, []byte{'\''}, false, false, false) {
return false
}
emitter.whitespace = false
emitter.indention = false
return true
}
func yaml_emitter_write_double_quoted_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
spaces := false
if !yaml_emitter_write_indicator(emitter, []byte{'"'}, true, false, false) {
return false
}
for i := 0; i < len(value); {
if !is_printable(value, i) || (!emitter.unicode && !is_ascii(value, i)) ||
is_bom(value, i) || is_break(value, i) ||
value[i] == '"' || value[i] == '\\' {
octet := value[i]
var w int
var v rune
switch {
case octet&0x80 == 0x00:
w, v = 1, rune(octet&0x7F)
case octet&0xE0 == 0xC0:
w, v = 2, rune(octet&0x1F)
case octet&0xF0 == 0xE0:
w, v = 3, rune(octet&0x0F)
case octet&0xF8 == 0xF0:
w, v = 4, rune(octet&0x07)
}
for k := 1; k < w; k++ {
octet = value[i+k]
v = (v << 6) + (rune(octet) & 0x3F)
}
i += w
if !put(emitter, '\\') {
return false
}
var ok bool
switch v {
case 0x00:
ok = put(emitter, '0')
case 0x07:
ok = put(emitter, 'a')
case 0x08:
ok = put(emitter, 'b')
case 0x09:
ok = put(emitter, 't')
case 0x0A:
ok = put(emitter, 'n')
case 0x0b:
ok = put(emitter, 'v')
case 0x0c:
ok = put(emitter, 'f')
case 0x0d:
ok = put(emitter, 'r')
case 0x1b:
ok = put(emitter, 'e')
case 0x22:
ok = put(emitter, '"')
case 0x5c:
ok = put(emitter, '\\')
case 0x85:
ok = put(emitter, 'N')
case 0xA0:
ok = put(emitter, '_')
case 0x2028:
ok = put(emitter, 'L')
case 0x2029:
ok = put(emitter, 'P')
default:
if v <= 0xFF {
ok = put(emitter, 'x')
w = 2
} else if v <= 0xFFFF {
ok = put(emitter, 'u')
w = 4
} else {
ok = put(emitter, 'U')
w = 8
}
for k := (w - 1) * 4; ok && k >= 0; k -= 4 {
digit := byte((v >> uint(k)) & 0x0F)
if digit < 10 {
ok = put(emitter, digit+'0')
} else {
ok = put(emitter, digit+'A'-10)
}
}
}
if !ok {
return false
}
spaces = false
} else if is_space(value, i) {
if allow_breaks && !spaces && emitter.column > emitter.best_width && i > 0 && i < len(value)-1 {
if !yaml_emitter_write_indent(emitter) {
return false
}
if is_space(value, i+1) {
if !put(emitter, '\\') {
return false
}
}
i += width(value[i])
} else if !write(emitter, value, &i) {
return false
}
spaces = true
} else {
if !write(emitter, value, &i) {
return false
}
spaces = false
}
}
if !yaml_emitter_write_indicator(emitter, []byte{'"'}, false, false, false) {
return false
}
emitter.whitespace = false
emitter.indention = false
return true
}
func yaml_emitter_write_block_scalar_hints(emitter *yaml_emitter_t, value []byte) bool {
if is_space(value, 0) || is_break(value, 0) {
indent_hint := []byte{'0' + byte(emitter.best_indent)}
if !yaml_emitter_write_indicator(emitter, indent_hint, false, false, false) {
return false
}
}
emitter.open_ended = false
var chomp_hint [1]byte
if len(value) == 0 {
chomp_hint[0] = '-'
} else {
i := len(value) - 1
for value[i]&0xC0 == 0x80 {
i--
}
if !is_break(value, i) {
chomp_hint[0] = '-'
} else if i == 0 {
chomp_hint[0] = '+'
emitter.open_ended = true
} else {
i--
for value[i]&0xC0 == 0x80 {
i--
}
if is_break(value, i) {
chomp_hint[0] = '+'
emitter.open_ended = true
}
}
}
if chomp_hint[0] != 0 {
if !yaml_emitter_write_indicator(emitter, chomp_hint[:], false, false, false) {
return false
}
}
return true
}
func yaml_emitter_write_literal_scalar(emitter *yaml_emitter_t, value []byte) bool {
if !yaml_emitter_write_indicator(emitter, []byte{'|'}, true, false, false) {
return false
}
if !yaml_emitter_write_block_scalar_hints(emitter, value) {
return false
}
if !put_break(emitter) {
return false
}
emitter.indention = true
emitter.whitespace = true
breaks := true
for i := 0; i < len(value); {
if is_break(value, i) {
if !write_break(emitter, value, &i) {
return false
}
emitter.indention = true
breaks = true
} else {
if breaks {
if !yaml_emitter_write_indent(emitter) {
return false
}
}
if !write(emitter, value, &i) {
return false
}
emitter.indention = false
breaks = false
}
}
return true
}
func yaml_emitter_write_folded_scalar(emitter *yaml_emitter_t, value []byte) bool {
if !yaml_emitter_write_indicator(emitter, []byte{'>'}, true, false, false) {
return false
}
if !yaml_emitter_write_block_scalar_hints(emitter, value) {
return false
}
if !put_break(emitter) {
return false
}
emitter.indention = true
emitter.whitespace = true
breaks := true
leading_spaces := true
for i := 0; i < len(value); {
if is_break(value, i) {
if !breaks && !leading_spaces && value[i] == '\n' {
k := 0
for is_break(value, k) {
k += width(value[k])
}
if !is_blankz(value, k) {
if !put_break(emitter) {
return false
}
}
}
if !write_break(emitter, value, &i) {
return false
}
emitter.indention = true
breaks = true
} else {
if breaks {
if !yaml_emitter_write_indent(emitter) {
return false
}
leading_spaces = is_blank(value, i)
}
if !breaks && is_space(value, i) && !is_space(value, i+1) && emitter.column > emitter.best_width {
if !yaml_emitter_write_indent(emitter) {
return false
}
i += width(value[i])
} else {
if !write(emitter, value, &i) {
return false
}
}
emitter.indention = false
breaks = false
}
}
return true
}