3 //! This module contains the definitions for options and names for common options.
4 //! Options are used to set custom parameters in e.g. decoders or muxers.
6 //! As a rule target for options should provide a list of supported options and ignore unknown options.
11 /// A list specifying option parsing and validating errors.
12 #[derive(Clone,Copy,Debug,PartialEq)]
13 pub enum OptionError {
14 /// Input is not intended for the current option definition.
16 /// Option value is not in the expected format.
18 /// Option value was not in the range.
24 /// A specialised `Result` type for option parsing/validation.
25 pub type OptionResult<T> = Result<T, OptionError>;
27 /// Option definition type.
29 pub enum NAOptionDefinitionType {
30 /// Option may just be present.
32 /// Option is a boolean value.
34 /// Option is an integer with optional minimum and maximum value.
35 Int(Option<i64>, Option<i64>),
36 /// Option is a floating point number with optional minimum and maximum value.
37 Float(Option<f64>, Option<f64>),
38 /// Option is a string with an optional list of allowed values.
39 String(Option<&'static [&'static str]>),
40 /// Option is some binary data.
44 /// Option definition.
46 pub struct NAOptionDefinition {
48 pub name: &'static str,
50 pub description: &'static str,
52 pub opt_type: NAOptionDefinitionType,
55 impl NAOptionDefinition {
56 /// Tries to parse input string(s) as an option and returns new option and number of arguments used (1 or 2) on success.
57 pub fn parse(&self, name: &String, value: Option<&String>) -> OptionResult<(NAOption, usize)> {
58 let no_name = "no".to_owned() + self.name;
59 let opt_no_name = "--no".to_owned() + self.name;
60 if name == &no_name || name == &opt_no_name {
62 NAOptionDefinitionType::Bool => return Ok((NAOption { name: self.name, value: NAValue::Bool(false) }, 1)),
63 _ => return Err(OptionError::InvalidFormat),
66 let opt_name = "--".to_owned() + self.name;
67 if self.name != name && &opt_name != name {
68 return Err(OptionError::WrongName);
71 NAOptionDefinitionType::None => Ok((NAOption { name: self.name, value: NAValue::None }, 1)),
72 NAOptionDefinitionType::Bool => Ok((NAOption { name: self.name, value: NAValue::Bool(true) }, 1)),
73 NAOptionDefinitionType::Int(_, _) => {
74 if let Some(str) = value {
75 let ret = str.parse::<i64>();
76 if let Ok(val) = ret {
77 let opt = NAOption { name: self.name, value: NAValue::Int(val) };
81 Err(OptionError::ParseError)
84 Err(OptionError::ParseError)
87 NAOptionDefinitionType::Float(_, _) => {
88 if let Some(str) = value {
89 let ret = str.parse::<f64>();
90 if let Ok(val) = ret {
91 let opt = NAOption { name: self.name, value: NAValue::Float(val) };
95 Err(OptionError::ParseError)
98 Err(OptionError::ParseError)
101 NAOptionDefinitionType::String(_) => {
102 if let Some(str) = value {
103 let opt = NAOption { name: self.name, value: NAValue::String(str.to_string()) };
107 Err(OptionError::ParseError)
110 _ => unimplemented!(),
113 /// Checks whether input option conforms to the definition i.e. whether it has proper format and it lies in range.
114 pub fn check(&self, option: &NAOption) -> OptionResult<()> {
115 if option.name != self.name {
116 return Err(OptionError::WrongName);
119 NAValue::None => Ok(()),
120 NAValue::Bool(_) => Ok(()),
121 NAValue::Int(intval) => {
122 match self.opt_type {
123 NAOptionDefinitionType::Int(minval, maxval) => {
124 if let Some(minval) = minval {
125 if intval < minval { return Err(OptionError::InvalidValue); }
127 if let Some(maxval) = maxval {
128 if intval > maxval { return Err(OptionError::InvalidValue); }
131 NAOptionDefinitionType::Float(minval, maxval) => {
132 let fval = intval as f64;
133 if let Some(minval) = minval {
134 if fval < minval { return Err(OptionError::InvalidValue); }
136 if let Some(maxval) = maxval {
137 if fval > maxval { return Err(OptionError::InvalidValue); }
140 _ => return Err(OptionError::InvalidFormat),
144 NAValue::Float(fval) => {
145 match self.opt_type {
146 NAOptionDefinitionType::Int(minval, maxval) => {
147 let intval = fval as i64;
148 if let Some(minval) = minval {
149 if intval < minval { return Err(OptionError::InvalidValue); }
151 if let Some(maxval) = maxval {
152 if intval > maxval { return Err(OptionError::InvalidValue); }
155 NAOptionDefinitionType::Float(minval, maxval) => {
156 if let Some(minval) = minval {
157 if fval < minval { return Err(OptionError::InvalidValue); }
159 if let Some(maxval) = maxval {
160 if fval > maxval { return Err(OptionError::InvalidValue); }
163 _ => return Err(OptionError::InvalidFormat),
167 NAValue::String(ref cur_str) => {
168 if let NAOptionDefinitionType::String(Some(ref strings)) = self.opt_type {
169 for str in strings.iter() {
174 Err(OptionError::InvalidValue)
179 NAValue::Data(_) => Ok(()),
184 impl fmt::Display for NAOptionDefinition {
185 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
186 match self.opt_type {
187 NAOptionDefinitionType::None => write!(f, "{}: {}", self.name, self.description),
188 NAOptionDefinitionType::Bool => write!(f, "[no]{}: {}", self.name, self.description),
189 NAOptionDefinitionType::String(ref str_list) => {
190 if let Some(ref opts) = str_list {
191 write!(f, "{} {}: {}", self.name, opts.join("|"), self.description)
193 write!(f, "{} <string>: {}", self.name, self.description)
196 NAOptionDefinitionType::Int(minval, maxval) => {
197 let range = match (&minval, &maxval) {
198 (Some(minval), None) => format!("{}-..", minval),
199 (None, Some(maxval)) => format!("..-{}", maxval),
200 (Some(minval), Some(maxval)) => format!("{}-{}", minval, maxval),
201 _ => "<integer>".to_string(),
203 write!(f, "{} {}: {}", self.name, range, self.description)
205 NAOptionDefinitionType::Float(minval, maxval) => {
206 let range = match (&minval, &maxval) {
207 (Some(minval), None) => format!("{}-..", minval),
208 (None, Some(maxval)) => format!("..-{}", maxval),
209 (Some(minval), Some(maxval)) => format!("{}-{}", minval, maxval),
210 _ => "<float>".to_string(),
212 write!(f, "{} {}: {}", self.name, range, self.description)
214 NAOptionDefinitionType::Data => write!(f, "{} <binary data>: {}", self.name, self.description),
220 #[derive(Clone,Debug,PartialEq)]
221 pub struct NAOption {
223 pub name: &'static str,
228 /// A list of accepted option values.
229 #[derive(Debug,Clone,PartialEq)]
237 /// Floating point value.
241 /// Binary data value.
245 /// Trait for all objects that handle `NAOption`.
246 pub trait NAOptionHandler {
247 /// Returns the options recognised by current object.
248 fn get_supported_options(&self) -> &[NAOptionDefinition];
249 /// Passes options for the object to set (or ignore).
250 fn set_options(&mut self, options: &[NAOption]);
251 /// Queries the current option value in the object (if present).
252 fn query_option_value(&self, name: &str) -> Option<NAValue>;
259 fn test_option_validation() {
260 let option = NAOption {name: "option", value: NAValue::Int(42) };
261 let mut def = NAOptionDefinition { name: "option", description: "", opt_type: NAOptionDefinitionType::Int(None, None) };
262 assert!(def.check(&option).is_ok());
263 def.opt_type = NAOptionDefinitionType::Int(None, Some(30));
264 assert_eq!(def.check(&option), Err(OptionError::InvalidValue));
265 def.opt_type = NAOptionDefinitionType::Int(Some(40), None);
266 assert!(def.check(&option).is_ok());
267 def.name = "option2";
268 assert_eq!(def.check(&option), Err(OptionError::WrongName));
269 let option = NAOption {name: "option", value: NAValue::String("test".to_string()) };
270 let mut def = NAOptionDefinition { name: "option", description: "", opt_type: NAOptionDefinitionType::String(None) };
271 assert!(def.check(&option).is_ok());
272 def.opt_type = NAOptionDefinitionType::String(Some(&["a string", "test string"]));
273 assert_eq!(def.check(&option), Err(OptionError::InvalidValue));
274 def.opt_type = NAOptionDefinitionType::String(Some(&["a string", "test"]));
275 assert!(def.check(&option).is_ok());
278 fn test_option_parsing() {
279 let mut def = NAOptionDefinition { name: "option", description: "", opt_type: NAOptionDefinitionType::Float(None, None) };
280 assert_eq!(def.parse(&"--option".to_string(), None), Err(OptionError::ParseError));
281 assert_eq!(def.parse(&"--nooption".to_string(), None), Err(OptionError::InvalidFormat));
282 assert_eq!(def.parse(&"--option".to_string(), Some(&"42".to_string())),
283 Ok((NAOption{name:"option",value: NAValue::Float(42.0)}, 2)));
284 def.opt_type = NAOptionDefinitionType::Float(None, Some(40.0));
285 assert_eq!(def.parse(&"--option".to_string(), Some(&"42".to_string())),
286 Err(OptionError::InvalidValue));
287 let def = NAOptionDefinition { name: "option", description: "", opt_type: NAOptionDefinitionType::Bool };
288 assert_eq!(def.parse(&"option".to_string(), None),
289 Ok((NAOption{name: "option", value: NAValue::Bool(true) }, 1)));
290 assert_eq!(def.parse(&"nooption".to_string(), None),
291 Ok((NAOption{name: "option", value: NAValue::Bool(false) }, 1)));