Changed read{,_line} to prevent heap allocation of slices.
diff --git a/scannerc.go b/scannerc.go
index 1066c4d..daad349 100644
--- a/scannerc.go
+++ b/scannerc.go
@@ -512,59 +512,59 @@
}
// Copy a character to a string buffer and advance pointers.
-func read(parser *yaml_parser_t, s *[]byte) bool {
+func read(parser *yaml_parser_t, s []byte) []byte {
w := width(parser.buffer[parser.buffer_pos])
if w == 0 {
panic("invalid character sequence")
}
- if len(*s) == 0 {
- *s = make([]byte, 0, 32)
+ if len(s) == 0 {
+ s = make([]byte, 0, 32)
}
- if w == 1 && len(*s)+w <= cap(*s) {
- *s = (*s)[:len(*s)+1]
- (*s)[len(*s)-1] = parser.buffer[parser.buffer_pos]
+ if w == 1 && len(s)+w <= cap(s) {
+ s = s[:len(s)+1]
+ s[len(s)-1] = parser.buffer[parser.buffer_pos]
parser.buffer_pos++
} else {
- *s = append(*s, parser.buffer[parser.buffer_pos:parser.buffer_pos+w]...)
+ s = append(s, parser.buffer[parser.buffer_pos:parser.buffer_pos+w]...)
parser.buffer_pos += w
}
parser.mark.index++
parser.mark.column++
parser.unread--
- return true
+ return s
}
// Copy a line break character to a string buffer and advance pointers.
-func read_line(parser *yaml_parser_t, s *[]byte) bool {
+func read_line(parser *yaml_parser_t, s []byte) []byte {
buf := parser.buffer
pos := parser.buffer_pos
switch {
case buf[pos] == '\r' && buf[pos+1] == '\n':
// CR LF . LF
- *s = append(*s, '\n')
+ s = append(s, '\n')
parser.buffer_pos += 2
parser.mark.index++
parser.unread--
case buf[pos] == '\r' || buf[pos] == '\n':
// CR|LF . LF
- *s = append(*s, '\n')
+ s = append(s, '\n')
parser.buffer_pos += 1
case buf[pos] == '\xC2' && buf[pos+1] == '\x85':
// NEL . LF
- *s = append(*s, '\n')
+ s = append(s, '\n')
parser.buffer_pos += 2
case buf[pos] == '\xE2' && buf[pos+1] == '\x80' && (buf[pos+2] == '\xA8' || buf[pos+2] == '\xA9'):
// LS|PS . LS|PS
- *s = append(*s, buf[parser.buffer_pos:pos+3]...)
+ s = append(s, buf[parser.buffer_pos:pos+3]...)
parser.buffer_pos += 3
default:
- return true
+ return s
}
parser.mark.index++
parser.mark.column = 0
parser.mark.line++
parser.unread--
- return true
+ return s
}
// Get the next token.
@@ -1605,9 +1605,7 @@
var s []byte
for is_alpha(parser.buffer, parser.buffer_pos) {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
}
@@ -1783,9 +1781,7 @@
}
for is_alpha(parser.buffer, parser.buffer_pos) {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
}
@@ -1929,18 +1925,14 @@
var s []byte
// Copy the '!' character.
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
// Copy all subsequent alphabetical and numerical characters.
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
}
for is_alpha(parser.buffer, parser.buffer_pos) {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
}
@@ -1948,9 +1940,7 @@
// Check if the trailing character is '!' and copy it.
if parser.buffer[parser.buffer_pos] == '!' {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
} else {
// It's either the '!' tag or not really a tag handle. If it's a %TAG
// directive, it's an error. If it's a tag token, it must be a part of URI.
@@ -2005,9 +1995,7 @@
return false
}
} else {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
}
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
@@ -2216,9 +2204,7 @@
// Consume the current line.
for !is_breakz(parser.buffer, parser.buffer_pos) {
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
return false
}
@@ -2229,9 +2215,7 @@
return false
}
- if !read_line(parser, &leading_break) {
- return false
- }
+ leading_break = read_line(parser, leading_break)
// Eat the following intendation spaces and line breaks.
if !yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks, start_mark, &end_mark) {
@@ -2298,9 +2282,8 @@
if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
return false
}
- if !read_line(parser, breaks) {
- return false
- }
+ // [Go] Should really be returning breaks instead.
+ *breaks = read_line(parser, *breaks)
*end_mark = parser.mark
}
@@ -2484,9 +2467,7 @@
}
} else {
// It is a non-escaped non-blank character.
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
}
if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
return false
@@ -2513,9 +2494,7 @@
if is_blank(parser.buffer, parser.buffer_pos) {
// Consume a space or a tab character.
if !leading_blanks {
- if !read(parser, &whitespaces) {
- return false
- }
+ whitespaces = read(parser, whitespaces)
} else {
skip(parser)
}
@@ -2527,14 +2506,10 @@
// Check if it is a first line break.
if !leading_blanks {
whitespaces = whitespaces[:0]
- if !read_line(parser, &leading_break) {
- return false
- }
+ leading_break = read_line(parser, leading_break)
leading_blanks = true
} else {
- if !read_line(parser, &trailing_breaks) {
- return false
- }
+ trailing_breaks = read_line(parser, trailing_breaks)
}
}
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
@@ -2659,9 +2634,7 @@
}
// Copy the character.
- if !read(parser, &s) {
- return false
- }
+ s = read(parser, s)
end_mark = parser.mark
if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
@@ -2691,9 +2664,7 @@
// Consume a space or a tab character.
if !leading_blanks {
- if !read(parser, &whitespaces) {
- return false
- }
+ whitespaces = read(parser, whitespaces)
} else {
skip(parser)
}
@@ -2705,14 +2676,10 @@
// Check if it is a first line break.
if !leading_blanks {
whitespaces = whitespaces[:0]
- if !read_line(parser, &leading_break) {
- return false
- }
+ leading_break = read_line(parser, leading_break)
leading_blanks = true
} else {
- if !read_line(parser, &trailing_breaks) {
- return false
- }
+ trailing_breaks = read_line(parser, trailing_breaks)
}
}
if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
