commit 39ca0f230351837f370b79c1801c23d35b938b7e Author: Matthias Fulz Date: Fri Oct 4 12:28:45 2019 +0200 Initial implementation diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..9a3a8d8 --- /dev/null +++ b/.gitignore @@ -0,0 +1,14 @@ +# ---> Go +# Binaries for programs and plugins +*.exe +*.exe~ +*.dll +*.so +*.dylib + +# Test binary, build with `go test -c` +*.test + +# Output of the go coverage tool, specifically when used with LiteIDE +*.out + diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..ff08398 --- /dev/null +++ b/LICENSE @@ -0,0 +1,319 @@ +GNU GENERAL PUBLIC LICENSE + +Version 2, June 1991 + +Copyright (C) 1989, 1991 Free Software Foundation, Inc. + +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 , USA + +Everyone is permitted to copy and distribute verbatim copies of this license +document, but changing it is not allowed. + +Preamble + +The licenses for most software are designed to take away your freedom to share +and change it. By contrast, the GNU General Public License is intended to +guarantee your freedom to share and change free software--to make sure the +software is free for all its users. This General Public License applies to +most of the Free Software Foundation's software and to any other program whose +authors commit to using it. (Some other Free Software Foundation software +is covered by the GNU Lesser General Public License instead.) You can apply +it to your programs, too. + +When we speak of free software, we are referring to freedom, not price. Our +General Public Licenses are designed to make sure that you have the freedom +to distribute copies of free software (and charge for this service if you +wish), that you receive source code or can get it if you want it, that you +can change the software or use pieces of it in new free programs; and that +you know you can do these things. + +To protect your rights, we need to make restrictions that forbid anyone to +deny you these rights or to ask you to surrender the rights. These restrictions +translate to certain responsibilities for you if you distribute copies of +the software, or if you modify it. + +For example, if you distribute copies of such a program, whether gratis or +for a fee, you must give the recipients all the rights that you have. You +must make sure that they, too, receive or can get the source code. And you +must show them these terms so they know their rights. + +We protect your rights with two steps: (1) copyright the software, and (2) +offer you this license which gives you legal permission to copy, distribute +and/or modify the software. + +Also, for each author's protection and ours, we want to make certain that +everyone understands that there is no warranty for this free software. If +the software is modified by someone else and passed on, we want its recipients +to know that what they have is not the original, so that any problems introduced +by others will not reflect on the original authors' reputations. + +Finally, any free program is threatened constantly by software patents. We +wish to avoid the danger that redistributors of a free program will individually +obtain patent licenses, in effect making the program proprietary. To prevent +this, we have made it clear that any patent must be licensed for everyone's +free use or not licensed at all. + +The precise terms and conditions for copying, distribution and modification +follow. + +TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + +0. This License applies to any program or other work which contains a notice +placed by the copyright holder saying it may be distributed under the terms +of this General Public License. The "Program", below, refers to any such program +or work, and a "work based on the Program" means either the Program or any +derivative work under copyright law: that is to say, a work containing the +Program or a portion of it, either verbatim or with modifications and/or translated +into another language. (Hereinafter, translation is included without limitation +in the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not covered +by this License; they are outside its scope. The act of running the Program +is not restricted, and the output from the Program is covered only if its +contents constitute a work based on the Program (independent of having been +made by running the Program). Whether that is true depends on what the Program +does. + +1. You may copy and distribute verbatim copies of the Program's source code +as you receive it, in any medium, provided that you conspicuously and appropriately +publish on each copy an appropriate copyright notice and disclaimer of warranty; +keep intact all the notices that refer to this License and to the absence +of any warranty; and give any other recipients of the Program a copy of this +License along with the Program. + +You may charge a fee for the physical act of transferring a copy, and you +may at your option offer warranty protection in exchange for a fee. + +2. You may modify your copy or copies of the Program or any portion of it, +thus forming a work based on the Program, and copy and distribute such modifications +or work under the terms of Section 1 above, provided that you also meet all +of these conditions: + +a) You must cause the modified files to carry prominent notices stating that +you changed the files and the date of any change. + +b) You must cause any work that you distribute or publish, that in whole or +in part contains or is derived from the Program or any part thereof, to be +licensed as a whole at no charge to all third parties under the terms of this +License. + +c) If the modified program normally reads commands interactively when run, +you must cause it, when started running for such interactive use in the most +ordinary way, to print or display an announcement including an appropriate +copyright notice and a notice that there is no warranty (or else, saying that +you provide a warranty) and that users may redistribute the program under +these conditions, and telling the user how to view a copy of this License. +(Exception: if the Program itself is interactive but does not normally print +such an announcement, your work based on the Program is not required to print +an announcement.) + +These requirements apply to the modified work as a whole. If identifiable +sections of that work are not derived from the Program, and can be reasonably +considered independent and separate works in themselves, then this License, +and its terms, do not apply to those sections when you distribute them as +separate works. But when you distribute the same sections as part of a whole +which is a work based on the Program, the distribution of the whole must be +on the terms of this License, whose permissions for other licensees extend +to the entire whole, and thus to each and every part regardless of who wrote +it. + +Thus, it is not the intent of this section to claim rights or contest your +rights to work written entirely by you; rather, the intent is to exercise +the right to control the distribution of derivative or collective works based +on the Program. + +In addition, mere aggregation of another work not based on the Program with +the Program (or with a work based on the Program) on a volume of a storage +or distribution medium does not bring the other work under the scope of this +License. + +3. You may copy and distribute the Program (or a work based on it, under Section +2) in object code or executable form under the terms of Sections 1 and 2 above +provided that you also do one of the following: + +a) Accompany it with the complete corresponding machine-readable source code, +which must be distributed under the terms of Sections 1 and 2 above on a medium +customarily used for software interchange; or, + +b) Accompany it with a written offer, valid for at least three years, to give +any third party, for a charge no more than your cost of physically performing +source distribution, a complete machine-readable copy of the corresponding +source code, to be distributed under the terms of Sections 1 and 2 above on +a medium customarily used for software interchange; or, + +c) Accompany it with the information you received as to the offer to distribute +corresponding source code. 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Each time you redistribute the Program (or any work based on the Program), +the recipient automatically receives a license from the original licensor +to copy, distribute or modify the Program subject to these terms and conditions. +You may not impose any further restrictions on the recipients' exercise of +the rights granted herein. You are not responsible for enforcing compliance +by third parties to this License. + +7. If, as a consequence of a court judgment or allegation of patent infringement +or for any other reason (not limited to patent issues), conditions are imposed +on you (whether by court order, agreement or otherwise) that contradict the +conditions of this License, they do not excuse you from the conditions of +this License. If you cannot distribute so as to satisfy simultaneously your +obligations under this License and any other pertinent obligations, then as +a consequence you may not distribute the Program at all. For example, if a +patent license would not permit royalty-free redistribution of the Program +by all those who receive copies directly or indirectly through you, then the +only way you could satisfy both it and this License would be to refrain entirely +from distribution of the Program. + +If any portion of this section is held invalid or unenforceable under any +particular circumstance, the balance of the section is intended to apply and +the section as a whole is intended to apply in other circumstances. + +It is not the purpose of this section to induce you to infringe any patents +or other property right claims or to contest validity of any such claims; +this section has the sole purpose of protecting the integrity of the free +software distribution system, which is implemented by public license practices. +Many people have made generous contributions to the wide range of software +distributed through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing to +distribute software through any other system and a licensee cannot impose +that choice. + +This section is intended to make thoroughly clear what is believed to be a +consequence of the rest of this License. + +8. If the distribution and/or use of the Program is restricted in certain +countries either by patents or by copyrighted interfaces, the original copyright +holder who places the Program under this License may add an explicit geographical +distribution limitation excluding those countries, so that distribution is +permitted only in or among countries not thus excluded. In such case, this +License incorporates the limitation as if written in the body of this License. + +9. The Free Software Foundation may publish revised and/or new versions of +the General Public License from time to time. Such new versions will be similar +in spirit to the present version, but may differ in detail to address new +problems or concerns. + +Each version is given a distinguishing version number. If the Program specifies +a version number of this License which applies to it and "any later version", +you have the option of following the terms and conditions either of that version +or of any later version published by the Free Software Foundation. If the +Program does not specify a version number of this License, you may choose +any version ever published by the Free Software Foundation. + +10. If you wish to incorporate parts of the Program into other free programs +whose distribution conditions are different, write to the author to ask for +permission. For software which is copyrighted by the Free Software Foundation, +write to the Free Software Foundation; we sometimes make exceptions for this. +Our decision will be guided by the two goals of preserving the free status +of all derivatives of our free software and of promoting the sharing and reuse +of software generally. + + NO WARRANTY + +11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR +THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE +STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM +"AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, +BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE +OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME +THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + +12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE +THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY +GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE +OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA +OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES +OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH +HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. +END OF TERMS AND CONDITIONS + +How to Apply These Terms to Your New Programs + +If you develop a new program, and you want it to be of the greatest possible +use to the public, the best way to achieve this is to make it free software +which everyone can redistribute and change under these terms. + +To do so, attach the following notices to the program. It is safest to attach +them to the start of each source file to most effectively convey the exclusion +of warranty; and each file should have at least the "copyright" line and a +pointer to where the full notice is found. + + + +Copyright (C) + +This program is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free Software +Foundation; either version 2 of the License, or (at your option) any later +version. + +This program is distributed in the hope that it will be useful, but WITHOUT +ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along with +this program; if not, write to the Free Software Foundation, Inc., 51 Franklin +Street, Fifth Floor, Boston, MA 02110-1301 , USA. + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this when +it starts in an interactive mode: + +Gnomovision version 69, Copyright (C) year name of author Gnomovision comes +with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, +and you are welcome to redistribute it under certain conditions; type `show +c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may be +called something other than `show w' and `show c'; they could even be mouse-clicks +or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your school, +if any, to sign a "copyright disclaimer" for the program, if necessary. Here +is a sample; alter the names: + +Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' +(which makes passes at compilers) written by James Hacker. + +< signature of Ty Coon > , 1 April 1989 Ty Coon, President of Vice This General +Public License does not permit incorporating your program into proprietary +programs. If your program is a subroutine library, you may consider it more +useful to permit linking proprietary applications with the library. If this +is what you want to do, use the GNU Lesser General Public License instead +of this License. diff --git a/README.md b/README.md new file mode 100644 index 0000000..23e47b1 --- /dev/null +++ b/README.md @@ -0,0 +1,4 @@ +# ssob + +Stupid simple object binary +gob like serializer intended to be easy to port and fast diff --git a/decoder.go b/decoder.go new file mode 100644 index 0000000..6f77f03 --- /dev/null +++ b/decoder.go @@ -0,0 +1,56 @@ +package ssob + +import ( + "encoding/binary" + "errors" + "io" + "reflect" + "sync" +) + +type Decoder struct { + mutex sync.Mutex + r io.Reader +} + +func NewDecoder(r io.Reader) *Decoder { + dec := new(Decoder) + dec.r = r + return dec +} + +func (dec *Decoder) Decode(e interface{}) (err error) { + return dec.DecodeValue(reflect.ValueOf(e)) +} + +func (dec *Decoder) DecodeValue(value reflect.Value) (err error) { + if value.Kind() == reflect.Invalid { + return errors.New("ssob: Cannot decode nil value") + } + + if value.Kind() == reflect.Ptr && value.IsNil() { + return errors.New("ssob: Cannot decode nil of type " + value.Type().String()) + } + + dec.mutex.Lock() + defer dec.mutex.Unlock() + + lb := make([]byte, 8) + err = binary.Read(dec.r, binary.BigEndian, lb) + if err != nil { + return err + } + l, n, err := unmarshalInt64(lb) + if err != nil || n != 8 { + return err + } + + bb := make([]byte, l) + err = binary.Read(dec.r, binary.BigEndian, bb) + if err != nil { + return err + } + + _, err = unmarshal(value.Interface(), bb) + return err +} diff --git a/encoder.go b/encoder.go new file mode 100644 index 0000000..bd39c04 --- /dev/null +++ b/encoder.go @@ -0,0 +1,46 @@ +package ssob + +import ( + "encoding/binary" + "errors" + "io" + "reflect" + "sync" +) + +type Encoder struct { + mutex sync.Mutex + w io.Writer +} + +func NewEncoder(w io.Writer) *Encoder { + enc := new(Encoder) + enc.w = w + return enc +} + +func (enc *Encoder) Encode(e interface{}) (err error) { + return enc.EncodeValue(reflect.ValueOf(e)) +} + +func (enc *Encoder) EncodeValue(value reflect.Value) (err error) { + if value.Kind() == reflect.Invalid { + return errors.New("ssob: Cannot encode nil value") + } + + if value.Kind() == reflect.Ptr && value.IsNil() { + return errors.New("ssob: Cannot encode nil of type " + value.Type().String()) + } + + b, err := marshal(value.Interface()) + if err != nil { + return err + } + bb := marshalInt64(int64(len(b))) + bb = append(bb, b...) + + enc.mutex.Lock() + defer enc.mutex.Unlock() + + return binary.Write(enc.w, binary.BigEndian, bb) +} diff --git a/marshal.go b/marshal.go new file mode 100644 index 0000000..560d369 --- /dev/null +++ b/marshal.go @@ -0,0 +1,260 @@ +package ssob + +import ( + "encoding/binary" + "errors" + "reflect" +) + +func marshalString(in string) (ret []byte) { + l := int64(len(in)) + b := marshalInt64(l) + b = append(b, []byte(in)...) + return b +} + +func marshalInt8(in int8) (ret []byte) { + return []byte{byte(in)} +} + +func marshalUint8(in uint8) (ret []byte) { + return []byte{byte(in)} +} + +func marshalInt16(in int16) (ret []byte) { + out := make([]byte, 2) + + binary.BigEndian.PutUint16(out, uint16(in)) + return out +} + +func marshalUint16(in uint16) (ret []byte) { + out := make([]byte, 2) + + binary.BigEndian.PutUint16(out, in) + return out +} + +func marshalInt32(in int32) (ret []byte) { + out := make([]byte, 4) + + binary.BigEndian.PutUint32(out, uint32(in)) + return out +} + +func marshalUint32(in uint32) (ret []byte) { + out := make([]byte, 4) + + binary.BigEndian.PutUint32(out, in) + return out +} + +func marshalFloat32(in float32) (ret []byte) { + out := make([]byte, 4) + + binary.BigEndian.PutUint32(out, uint32(in)) + return out +} + +func marshalInt64(in int64) (ret []byte) { + out := make([]byte, 8) + + binary.BigEndian.PutUint64(out, uint64(in)) + return out +} + +func marshalUint64(in uint64) (ret []byte) { + out := make([]byte, 8) + + binary.BigEndian.PutUint64(out, in) + return out +} + +func marshalFloat64(in float64) (ret []byte) { + out := make([]byte, 8) + + binary.BigEndian.PutUint64(out, uint64(in)) + return out +} + +type marshalFunc func(e interface{}) (ret []byte, err error) + +var encoderCache map[string]marshalFunc + +func init() { + encoderCache = make(map[string]marshalFunc) + encRegister(int8(0)) + encRegister(uint8(0)) + encRegister(int16(0)) + encRegister(uint16(0)) + encRegister(int32(0)) + encRegister(uint32(0)) + encRegister(float32(0)) + encRegister(int64(0)) + encRegister(uint64(0)) + encRegister(float64(0)) + encRegister(string("")) +} + +func encRegister(e interface{}) (err error) { + v := reflect.ValueOf(e) + t := reflect.TypeOf(e) + switch t.Kind() { + case reflect.Invalid: + return errors.New("ssob: Invalid type") + case reflect.Slice: + f := func(e interface{}) (ret []byte, err error) { + v := reflect.ValueOf(e) + l := v.Len() + ret, err = marshal(int64(l)) + if err != nil { + return nil, err + } + for i := 0; i < l; i++ { + b, err := marshal(v.Index(i).Interface()) + if err != nil { + return nil, err + } + ret = append(ret, b...) + } + + return ret, nil + } + encoderCache[string(t.Kind())] = f + case reflect.Struct: + f := func(e interface{}) (ret []byte, err error) { + n := v.NumField() + ret = []byte{} + for i := 0; i < n; i++ { + b, err := marshal(v.Field(i).Interface()) + if err != nil { + return nil, err + } + ret = append(ret, b...) + } + return ret, nil + } + encoderCache[t.Name()] = f + case reflect.Int8: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(int8); ok { + return marshalInt8(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected int8") + } + encoderCache[string(v.Kind())] = f + case reflect.Uint8: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(uint8); ok { + return marshalUint8(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected uint8") + } + encoderCache[string(v.Kind())] = f + case reflect.Int16: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(int16); ok { + return marshalInt16(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected int16") + } + encoderCache[string(v.Kind())] = f + case reflect.Uint16: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(uint16); ok { + return marshalUint16(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected uint16") + } + encoderCache[string(v.Kind())] = f + case reflect.Int32: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(int32); ok { + return marshalInt32(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected int32") + } + encoderCache[string(v.Kind())] = f + case reflect.Uint32: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(uint32); ok { + return marshalUint32(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected uint32") + } + encoderCache[string(v.Kind())] = f + case reflect.Float32: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(float32); ok { + return marshalFloat32(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected float32") + } + encoderCache[string(v.Kind())] = f + case reflect.Int64: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(int64); ok { + return marshalInt64(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected int64") + } + encoderCache[string(v.Kind())] = f + case reflect.Uint64: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(uint64); ok { + return marshalUint64(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected uint64") + } + encoderCache[string(v.Kind())] = f + case reflect.Float64: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(float64); ok { + return marshalFloat64(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected float64") + } + encoderCache[string(v.Kind())] = f + case reflect.String: + f := func(e interface{}) (ret []byte, err error) { + if i, ok := e.(string); ok { + return marshalString(i), nil + } + return nil, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected string") + } + encoderCache[string(v.Kind())] = f + default: + return errors.New("ssob: Unknown type " + string(v.Kind())) + } + + return nil +} + +func marshal(e interface{}) (ret []byte, err error) { + var key string + t := reflect.TypeOf(e) + v := reflect.ValueOf(e) + if t.Kind() == reflect.Ptr { + if v.IsNil() { + return nil, errors.New("ssob: Cannot marshal nil pointer") + } + p := reflect.Indirect(v) + return marshal(p.Interface()) + } + if t.Kind() == reflect.Struct { + key = reflect.TypeOf(e).Name() + } else { + key = string(t.Kind()) + } + + if f, ok := encoderCache[key]; ok { + return f(e) + } else { + err = encRegister(e) + if err != nil { + return nil, err + } + } + + return marshal(e) +} diff --git a/unmarshal.go b/unmarshal.go new file mode 100644 index 0000000..8c87c4f --- /dev/null +++ b/unmarshal.go @@ -0,0 +1,350 @@ +package ssob + +import ( + "encoding/binary" + "errors" + "reflect" +) + +func unmarshalString(in []byte) (ret string, n int, err error) { + if len(in) < 8 { + return "", 0, errors.New("ssob: Invalid input to decode string") + } + l := int64(binary.BigEndian.Uint64(in)) + + if len(in[8:]) < int(l) { + return "", 0, errors.New("ssob: Invalid length of string") + } + return string(in[8 : l+8]), int(l) + 8, nil +} + +func unmarshalInt8(in []byte) (ret int8, n int, err error) { + if len(in) < 1 { + return 0, 0, errors.New("ssob: Invalid input to decode int8") + } + + return int8(in[0]), 1, nil +} + +func unmarshalUint8(in []byte) (ret uint8, n int, err error) { + if len(in) < 1 { + return 0, 0, errors.New("ssob: Invalid input to decode uint8") + } + + return uint8(in[0]), 1, nil +} + +func unmarshalInt16(in []byte) (ret int16, n int, err error) { + if len(in) < 2 { + return 0, 0, errors.New("ssob: Invalid input to decode int16") + } + + return int16(binary.BigEndian.Uint16(in[0:2])), 2, nil +} + +func unmarshalUint16(in []byte) (ret uint16, n int, err error) { + if len(in) < 2 { + return 0, 0, errors.New("ssob: Invalid input to decode uint16") + } + + return binary.BigEndian.Uint16(in[0:1]), 2, nil +} + +func unmarshalInt32(in []byte) (ret int32, n int, err error) { + if len(in) < 4 { + return 0, 0, errors.New("ssob: Invalid input to decode int32") + } + + return int32(binary.BigEndian.Uint32(in[0:4])), 4, nil +} + +func unmarshalUint32(in []byte) (ret uint32, n int, err error) { + if len(in) < 4 { + return 0, 0, errors.New("ssob: Invalid input to decode uint32") + } + + return binary.BigEndian.Uint32(in[0:4]), 4, nil +} + +func unmarshalFloat32(in []byte) (ret float32, n int, err error) { + if len(in) < 4 { + return 0, 0, errors.New("ssob: Invalid input to decode float32") + } + + return float32(binary.BigEndian.Uint64(in[0:4])), 4, nil +} + +func unmarshalInt64(in []byte) (ret int64, n int, err error) { + if len(in) < 8 { + return 0, 0, errors.New("ssob: Invalid input to decode int64") + } + + return int64(binary.BigEndian.Uint64(in[0:8])), 8, nil +} + +func unmarshalUint64(in []byte) (ret uint64, n int, err error) { + if len(in) < 8 { + return 0, 0, errors.New("ssob: Invalid input to decode uint64") + } + + return binary.BigEndian.Uint64(in[0:8]), 8, nil +} + +func unmarshalFloat64(in []byte) (ret float64, n int, err error) { + if len(in) < 8 { + return 0, 0, errors.New("ssob: Invalid input to decode float64") + } + + return float64(binary.BigEndian.Uint64(in[0:8])), 8, nil +} + +type unmarshalFunc func(e interface{}, in []byte) (n int, err error) + +var decoderCache map[string]unmarshalFunc + +func init() { + decoderCache = make(map[string]unmarshalFunc) + decRegister(int8(0)) + decRegister(uint8(0)) + decRegister(int16(0)) + decRegister(uint16(0)) + decRegister(int32(0)) + decRegister(uint32(0)) + decRegister(float32(0)) + decRegister(int64(0)) + decRegister(uint64(0)) + decRegister(float64(0)) + decRegister(string("")) +} + +func decRegister(e interface{}) (err error) { + t := reflect.TypeOf(e) + v := reflect.ValueOf(e) + switch t.Kind() { + case reflect.Invalid: + return errors.New("ssob: Invalid type") + case reflect.Slice: + return errors.New("ssob: Unsupported type") + case reflect.Struct: + f := func(e interface{}, in []byte) (n int, err error) { + t := reflect.TypeOf(e) + v := reflect.ValueOf(e) + pos := 0 + + if t.Kind() != reflect.Ptr || v.IsNil() { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + + vi := reflect.Indirect(v) + l := vi.NumField() + for i := 0; i < l; i++ { + ni, err := unmarshal(vi.Field(i).Addr().Interface(), in[pos:]) + pos += ni + if err != nil { + return pos, err + } + } + + return pos, nil + } + decoderCache[t.Name()] = f + case reflect.Int8: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*int8); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalInt8(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *int8") + } + decoderCache[string(v.Kind())] = f + case reflect.Uint8: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*uint8); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalUint8(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *uint8") + } + decoderCache[string(v.Kind())] = f + case reflect.Int16: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*int16); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalInt16(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *int16") + } + decoderCache[string(v.Kind())] = f + case reflect.Uint16: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*uint16); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalUint16(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *uint16") + } + decoderCache[string(v.Kind())] = f + case reflect.Int32: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*int32); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalInt32(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *int32") + } + decoderCache[string(v.Kind())] = f + case reflect.Uint32: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*uint32); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalUint32(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *uint32") + } + decoderCache[string(v.Kind())] = f + case reflect.Float32: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*float32); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalFloat32(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *float32") + } + decoderCache[string(v.Kind())] = f + case reflect.Int64: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*int64); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalInt64(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *int64") + } + decoderCache[string(v.Kind())] = f + case reflect.Uint64: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*uint64); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalUint64(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *uint64") + } + decoderCache[string(v.Kind())] = f + case reflect.Float64: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*float64); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalFloat64(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *float64") + } + decoderCache[string(v.Kind())] = f + case reflect.String: + f := func(e interface{}, in []byte) (n int, err error) { + if i, ok := e.(*string); ok { + if i == nil { + return 0, errors.New("ssob: Cannot unmarshal to nil pointer") + } + *i, n, err = unmarshalString(in) + if err != nil { + return 0, err + } + return n, err + } + return 0, errors.New("ssob: Incompatible type " + string(v.Kind()) + " - expected *string") + } + decoderCache[string(v.Kind())] = f + default: + return errors.New("ssob: Unknown type " + string(v.Kind())) + } + + return nil +} + +func unmarshal(e interface{}, in []byte) (n int, err error) { + var key string + t := reflect.TypeOf(e) + v := reflect.ValueOf(e) + if t.Kind() != reflect.Ptr || v.IsNil() { + return 0, errors.New("ssob: Need a pointer that is fully allocated for unmarshalling") + } + + p := reflect.Indirect(v) + if p.Kind() != reflect.Ptr { + if p.Kind() == reflect.Struct { + key = reflect.TypeOf(p.Interface()).Name() + } else { + key = string(p.Kind()) + } + + if f, ok := decoderCache[key]; ok { + return f(v.Interface(), in) + } else { + err = decRegister(p.Interface()) + if err != nil { + return 0, err + } + } + } + + return unmarshal(e, in) +}