diff options
Diffstat (limited to 'vendor/github.com/jesseduffield/yaml/emitterc.go')
-rw-r--r-- | vendor/github.com/jesseduffield/yaml/emitterc.go | 1685 |
1 files changed, 1685 insertions, 0 deletions
diff --git a/vendor/github.com/jesseduffield/yaml/emitterc.go b/vendor/github.com/jesseduffield/yaml/emitterc.go new file mode 100644 index 000000000..cf0db118a --- /dev/null +++ b/vendor/github.com/jesseduffield/yaml/emitterc.go @@ -0,0 +1,1685 @@ +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 achor. +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 + ) < |