diff options
Diffstat (limited to 'Godeps/_workspace/src/github.com/lib/pq/encode.go')
| -rw-r--r-- | Godeps/_workspace/src/github.com/lib/pq/encode.go | 538 |
1 files changed, 0 insertions, 538 deletions
diff --git a/Godeps/_workspace/src/github.com/lib/pq/encode.go b/Godeps/_workspace/src/github.com/lib/pq/encode.go deleted file mode 100644 index 88422eb3d..000000000 --- a/Godeps/_workspace/src/github.com/lib/pq/encode.go +++ /dev/null @@ -1,538 +0,0 @@ -package pq - -import ( - "bytes" - "database/sql/driver" - "encoding/binary" - "encoding/hex" - "fmt" - "math" - "strconv" - "strings" - "sync" - "time" - - "github.com/lib/pq/oid" -) - -func binaryEncode(parameterStatus *parameterStatus, x interface{}) []byte { - switch v := x.(type) { - case []byte: - return v - default: - return encode(parameterStatus, x, oid.T_unknown) - } - panic("not reached") -} - -func encode(parameterStatus *parameterStatus, x interface{}, pgtypOid oid.Oid) []byte { - switch v := x.(type) { - case int64: - return strconv.AppendInt(nil, v, 10) - case float64: - return strconv.AppendFloat(nil, v, 'f', -1, 64) - case []byte: - if pgtypOid == oid.T_bytea { - return encodeBytea(parameterStatus.serverVersion, v) - } - - return v - case string: - if pgtypOid == oid.T_bytea { - return encodeBytea(parameterStatus.serverVersion, []byte(v)) - } - - return []byte(v) - case bool: - return strconv.AppendBool(nil, v) - case time.Time: - return formatTs(v) - - default: - errorf("encode: unknown type for %T", v) - } - - panic("not reached") -} - -func decode(parameterStatus *parameterStatus, s []byte, typ oid.Oid, f format) interface{} { - if f == formatBinary { - return binaryDecode(parameterStatus, s, typ) - } else { - return textDecode(parameterStatus, s, typ) - } -} - -func binaryDecode(parameterStatus *parameterStatus, s []byte, typ oid.Oid) interface{} { - switch typ { - case oid.T_bytea: - return s - case oid.T_int8: - return int64(binary.BigEndian.Uint64(s)) - case oid.T_int4: - return int64(int32(binary.BigEndian.Uint32(s))) - case oid.T_int2: - return int64(int16(binary.BigEndian.Uint16(s))) - - default: - errorf("don't know how to decode binary parameter of type %u", uint32(typ)) - } - - panic("not reached") -} - -func textDecode(parameterStatus *parameterStatus, s []byte, typ oid.Oid) interface{} { - switch typ { - case oid.T_bytea: - return parseBytea(s) - case oid.T_timestamptz: - return parseTs(parameterStatus.currentLocation, string(s)) - case oid.T_timestamp, oid.T_date: - return parseTs(nil, string(s)) - case oid.T_time: - return mustParse("15:04:05", typ, s) - case oid.T_timetz: - return mustParse("15:04:05-07", typ, s) - case oid.T_bool: - return s[0] == 't' - case oid.T_int8, oid.T_int4, oid.T_int2: - i, err := strconv.ParseInt(string(s), 10, 64) - if err != nil { - errorf("%s", err) - } - return i - case oid.T_float4, oid.T_float8: - bits := 64 - if typ == oid.T_float4 { - bits = 32 - } - f, err := strconv.ParseFloat(string(s), bits) - if err != nil { - errorf("%s", err) - } - return f - } - - return s -} - -// appendEncodedText encodes item in text format as required by COPY -// and appends to buf -func appendEncodedText(parameterStatus *parameterStatus, buf []byte, x interface{}) []byte { - switch v := x.(type) { - case int64: - return strconv.AppendInt(buf, v, 10) - case float64: - return strconv.AppendFloat(buf, v, 'f', -1, 64) - case []byte: - encodedBytea := encodeBytea(parameterStatus.serverVersion, v) - return appendEscapedText(buf, string(encodedBytea)) - case string: - return appendEscapedText(buf, v) - case bool: - return strconv.AppendBool(buf, v) - case time.Time: - return append(buf, formatTs(v)...) - case nil: - return append(buf, "\\N"...) - default: - errorf("encode: unknown type for %T", v) - } - - panic("not reached") -} - -func appendEscapedText(buf []byte, text string) []byte { - escapeNeeded := false - startPos := 0 - var c byte - - // check if we need to escape - for i := 0; i < len(text); i++ { - c = text[i] - if c == '\\' || c == '\n' || c == '\r' || c == '\t' { - escapeNeeded = true - startPos = i - break - } - } - if !escapeNeeded { - return append(buf, text...) - } - - // copy till first char to escape, iterate the rest - result := append(buf, text[:startPos]...) - for i := startPos; i < len(text); i++ { - c = text[i] - switch c { - case '\\': - result = append(result, '\\', '\\') - case '\n': - result = append(result, '\\', 'n') - case '\r': - result = append(result, '\\', 'r') - case '\t': - result = append(result, '\\', 't') - default: - result = append(result, c) - } - } - return result -} - -func mustParse(f string, typ oid.Oid, s []byte) time.Time { - str := string(s) - - // check for a 30-minute-offset timezone - if (typ == oid.T_timestamptz || typ == oid.T_timetz) && - str[len(str)-3] == ':' { - f += ":00" - } - t, err := time.Parse(f, str) - if err != nil { - errorf("decode: %s", err) - } - return t -} - -func expect(str, char string, pos int) { - if c := str[pos : pos+1]; c != char { - errorf("expected '%v' at position %v; got '%v'", char, pos, c) - } -} - -func mustAtoi(str string) int { - result, err := strconv.Atoi(str) - if err != nil { - errorf("expected number; got '%v'", str) - } - return result -} - -// The location cache caches the time zones typically used by the client. -type locationCache struct { - cache map[int]*time.Location - lock sync.Mutex -} - -// All connections share the same list of timezones. Benchmarking shows that -// about 5% speed could be gained by putting the cache in the connection and -// losing the mutex, at the cost of a small amount of memory and a somewhat -// significant increase in code complexity. -var globalLocationCache *locationCache = newLocationCache() - -func newLocationCache() *locationCache { - return &locationCache{cache: make(map[int]*time.Location)} -} - -// Returns the cached timezone for the specified offset, creating and caching -// it if necessary. -func (c *locationCache) getLocation(offset int) *time.Location { - c.lock.Lock() - defer c.lock.Unlock() - - location, ok := c.cache[offset] - if !ok { - location = time.FixedZone("", offset) - c.cache[offset] = location - } - - return location -} - -var infinityTsEnabled = false -var infinityTsNegative time.Time -var infinityTsPositive time.Time - -const ( - infinityTsEnabledAlready = "pq: infinity timestamp enabled already" - infinityTsNegativeMustBeSmaller = "pq: infinity timestamp: negative value must be smaller (before) than positive" -) - -/* - * If EnableInfinityTs is not called, "-infinity" and "infinity" will return - * []byte("-infinity") and []byte("infinity") respectively, and potentially - * cause error "sql: Scan error on column index 0: unsupported driver -> Scan pair: []uint8 -> *time.Time", - * when scanning into a time.Time value. - * - * Once EnableInfinityTs has been called, all connections created using this - * driver will decode Postgres' "-infinity" and "infinity" for "timestamp", - * "timestamp with time zone" and "date" types to the predefined minimum and - * maximum times, respectively. When encoding time.Time values, any time which - * equals or preceeds the predefined minimum time will be encoded to - * "-infinity". Any values at or past the maximum time will similarly be - * encoded to "infinity". - * - * - * If EnableInfinityTs is called with negative >= positive, it will panic. - * Calling EnableInfinityTs after a connection has been established results in - * undefined behavior. If EnableInfinityTs is called more than once, it will - * panic. - */ -func EnableInfinityTs(negative time.Time, positive time.Time) { - if infinityTsEnabled { - panic(infinityTsEnabledAlready) - } - if !negative.Before(positive) { - panic(infinityTsNegativeMustBeSmaller) - } - infinityTsEnabled = true - infinityTsNegative = negative - infinityTsPositive = positive -} - -/* - * Testing might want to toggle infinityTsEnabled - */ -func disableInfinityTs() { - infinityTsEnabled = false -} - -// This is a time function specific to the Postgres default DateStyle -// setting ("ISO, MDY"), the only one we currently support. This -// accounts for the discrepancies between the parsing available with -// time.Parse and the Postgres date formatting quirks. -func parseTs(currentLocation *time.Location, str string) interface{} { - switch str { - case "-infinity": - if infinityTsEnabled { - return infinityTsNegative - } - return []byte(str) - case "infinity": - if infinityTsEnabled { - return infinityTsPositive - } - return []byte(str) - } - - monSep := strings.IndexRune(str, '-') - // this is Gregorian year, not ISO Year - // In Gregorian system, the year 1 BC is followed by AD 1 - year := mustAtoi(str[:monSep]) - daySep := monSep + 3 - month := mustAtoi(str[monSep+1 : daySep]) - expect(str, "-", daySep) - timeSep := daySep + 3 - day := mustAtoi(str[daySep+1 : timeSep]) - - var hour, minute, second int - if len(str) > monSep+len("01-01")+1 { - expect(str, " ", timeSep) - minSep := timeSep + 3 - expect(str, ":", minSep) - hour = mustAtoi(str[timeSep+1 : minSep]) - secSep := minSep + 3 - expect(str, ":", secSep) - minute = mustAtoi(str[minSep+1 : secSep]) - secEnd := secSep + 3 - second = mustAtoi(str[secSep+1 : secEnd]) - } - remainderIdx := monSep + len("01-01 00:00:00") + 1 - // Three optional (but ordered) sections follow: the - // fractional seconds, the time zone offset, and the BC - // designation. We set them up here and adjust the other - // offsets if the preceding sections exist. - - nanoSec := 0 - tzOff := 0 - - if remainderIdx < len(str) && str[remainderIdx:remainderIdx+1] == "." { - fracStart := remainderIdx + 1 - fracOff := strings.IndexAny(str[fracStart:], "-+ ") - if fracOff < 0 { - fracOff = len(str) - fracStart - } - fracSec := mustAtoi(str[fracStart : fracStart+fracOff]) - nanoSec = fracSec * (1000000000 / int(math.Pow(10, float64(fracOff)))) - - remainderIdx += fracOff + 1 - } - if tzStart := remainderIdx; tzStart < len(str) && (str[tzStart:tzStart+1] == "-" || str[tzStart:tzStart+1] == "+") { - // time zone separator is always '-' or '+' (UTC is +00) - var tzSign int - if c := str[tzStart : tzStart+1]; c == "-" { - tzSign = -1 - } else if c == "+" { - tzSign = +1 - } else { - errorf("expected '-' or '+' at position %v; got %v", tzStart, c) - } - tzHours := mustAtoi(str[tzStart+1 : tzStart+3]) - remainderIdx += 3 - var tzMin, tzSec int - if tzStart+3 < len(str) && str[tzStart+3:tzStart+4] == ":" { - tzMin = mustAtoi(str[tzStart+4 : tzStart+6]) - remainderIdx += 3 - } - if tzStart+6 < len(str) && str[tzStart+6:tzStart+7] == ":" { - tzSec = mustAtoi(str[tzStart+7 : tzStart+9]) - remainderIdx += 3 - } - tzOff = tzSign * ((tzHours * 60 * 60) + (tzMin * 60) + tzSec) - } - var isoYear int - if remainderIdx < len(str) && str[remainderIdx:remainderIdx+3] == " BC" { - isoYear = 1 - year - remainderIdx += 3 - } else { - isoYear = year - } - if remainderIdx < len(str) { - errorf("expected end of input, got %v", str[remainderIdx:]) - } - t := time.Date(isoYear, time.Month(month), day, - hour, minute, second, nanoSec, - globalLocationCache.getLocation(tzOff)) - - if currentLocation != nil { - // Set the location of the returned Time based on the session's - // TimeZone value, but only if the local time zone database agrees with - // the remote database on the offset. - lt := t.In(currentLocation) - _, newOff := lt.Zone() - if newOff == tzOff { - t = lt - } - } - - return t -} - -// formatTs formats t into a format postgres understands. -func formatTs(t time.Time) (b []byte) { - if infinityTsEnabled { - // t <= -infinity : ! (t > -infinity) - if !t.After(infinityTsNegative) { - return []byte("-infinity") - } - // t >= infinity : ! (!t < infinity) - if !t.Before(infinityTsPositive) { - return []byte("infinity") - } - } - // Need to send dates before 0001 A.D. with " BC" suffix, instead of the - // minus sign preferred by Go. - // Beware, "0000" in ISO is "1 BC", "-0001" is "2 BC" and so on - bc := false - if t.Year() <= 0 { - // flip year sign, and add 1, e.g: "0" will be "1", and "-10" will be "11" - t = t.AddDate((-t.Year())*2+1, 0, 0) - bc = true - } - b = []byte(t.Format(time.RFC3339Nano)) - - _, offset := t.Zone() - offset = offset % 60 - if offset != 0 { - // RFC3339Nano already printed the minus sign - if offset < 0 { - offset = -offset - } - - b = append(b, ':') - if offset < 10 { - b = append(b, '0') - } - b = strconv.AppendInt(b, int64(offset), 10) - } - - if bc { - b = append(b, " BC"...) - } - return b -} - -// Parse a bytea value received from the server. Both "hex" and the legacy -// "escape" format are supported. -func parseBytea(s []byte) (result []byte) { - if len(s) >= 2 && bytes.Equal(s[:2], []byte("\\x")) { - // bytea_output = hex - s = s[2:] // trim off leading "\\x" - result = make([]byte, hex.DecodedLen(len(s))) - _, err := hex.Decode(result, s) - if err != nil { - errorf("%s", err) - } - } else { - // bytea_output = escape - for len(s) > 0 { - if s[0] == '\\' { - // escaped '\\' - if len(s) >= 2 && s[1] == '\\' { - result = append(result, '\\') - s = s[2:] - continue - } - - // '\\' followed by an octal number - if len(s) < 4 { - errorf("invalid bytea sequence %v", s) - } - r, err := strconv.ParseInt(string(s[1:4]), 8, 9) - if err != nil { - errorf("could not parse bytea value: %s", err.Error()) - } - result = append(result, byte(r)) - s = s[4:] - } else { - // We hit an unescaped, raw byte. Try to read in as many as - // possible in one go. - i := bytes.IndexByte(s, '\\') - if i == -1 { - result = append(result, s...) - break - } - result = append(result, s[:i]...) - s = s[i:] - } - } - } - - return result -} - -func encodeBytea(serverVersion int, v []byte) (result []byte) { - if serverVersion >= 90000 { - // Use the hex format if we know that the server supports it - result = make([]byte, 2+hex.EncodedLen(len(v))) - result[0] = '\\' - result[1] = 'x' - hex.Encode(result[2:], v) - } else { - // .. or resort to "escape" - for _, b := range v { - if b == '\\' { - result = append(result, '\\', '\\') - } else if b < 0x20 || b > 0x7e { - result = append(result, []byte(fmt.Sprintf("\\%03o", b))...) - } else { - result = append(result, b) - } - } - } - - return result -} - -// NullTime represents a time.Time that may be null. NullTime implements the -// sql.Scanner interface so it can be used as a scan destination, similar to -// sql.NullString. -type NullTime struct { - Time time.Time - Valid bool // Valid is true if Time is not NULL -} - -// Scan implements the Scanner interface. -func (nt *NullTime) Scan(value interface{}) error { - nt.Time, nt.Valid = value.(time.Time) - return nil -} - -// Value implements the driver Valuer interface. -func (nt NullTime) Value() (driver.Value, error) { - if !nt.Valid { - return nil, nil - } - return nt.Time, nil -} |