cloudflared-mirror/vendor/github.com/kshvakov/clickhouse/helpers.go

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package clickhouse
import (
"bytes"
"database/sql/driver"
"fmt"
"reflect"
"regexp"
"strings"
"time"
)
func numInput(query string) int {
var (
count int
args = make(map[string]struct{})
reader = bytes.NewReader([]byte(query))
quote, keyword bool
inBetween bool
like = newMatcher("like")
limit = newMatcher("limit")
between = newMatcher("between")
and = newMatcher("and")
)
for {
if char, _, err := reader.ReadRune(); err == nil {
switch char {
case '\'', '`':
quote = !quote
}
if quote {
continue
}
switch {
case char == '?' && keyword:
count++
case char == '@':
if param := paramParser(reader); len(param) != 0 {
if _, found := args[param]; !found {
args[param] = struct{}{}
count++
}
}
case
char == '=',
char == '<',
char == '>',
char == '(',
char == ',',
char == '[':
keyword = true
default:
if limit.matchRune(char) || like.matchRune(char) {
keyword = true
} else if between.matchRune(char) {
keyword = true
inBetween = true
} else if inBetween && and.matchRune(char) {
keyword = true
inBetween = false
} else {
keyword = keyword && (char == ' ' || char == '\t' || char == '\n')
}
}
} else {
break
}
}
return count
}
func paramParser(reader *bytes.Reader) string {
var name bytes.Buffer
for {
if char, _, err := reader.ReadRune(); err == nil {
if char == '_' || char >= '0' && char <= '9' || 'a' <= char && char <= 'z' || 'A' <= char && char <= 'Z' {
name.WriteRune(char)
} else {
reader.UnreadRune()
break
}
} else {
break
}
}
return name.String()
}
var selectRe = regexp.MustCompile(`\s+SELECT\s+`)
func isInsert(query string) bool {
if f := strings.Fields(query); len(f) > 2 {
return strings.EqualFold("INSERT", f[0]) && strings.EqualFold("INTO", f[1]) && !selectRe.MatchString(strings.ToUpper(query))
}
return false
}
func quote(v driver.Value) string {
switch v := reflect.ValueOf(v); v.Kind() {
case reflect.Slice:
values := make([]string, 0, v.Len())
for i := 0; i < v.Len(); i++ {
values = append(values, quote(v.Index(i).Interface()))
}
return strings.Join(values, ", ")
}
switch v := v.(type) {
case string:
return "'" + strings.NewReplacer(`\`, `\\`, `'`, `\'`).Replace(v) + "'"
case time.Time:
return formatTime(v)
}
return fmt.Sprint(v)
}
func formatTime(value time.Time) string {
if (value.Hour() + value.Minute() + value.Second() + value.Nanosecond()) == 0 {
return fmt.Sprintf("toDate(%d)", int(int16(value.Unix()/24/3600)))
}
return fmt.Sprintf("toDateTime(%d)", int(uint32(value.Unix())))
}