-use anyhow::{anyhow, Result};
use float_next_after::NextAfter;
use num::{Bounded, Zero};
use ordered_float::OrderedFloat;
use std::{
collections::{hash_map::Entry, HashMap},
- fmt::Display,
- iter::{repeat, Peekable},
- str::Chars,
+ error::Error as StdError,
+ fmt::{Display, Formatter, Result as FmtResult},
+ iter::repeat,
};
use crate::endian::{Endian, ToBytes};
-pub fn sack(input: &str, endian: Endian) -> Result<Vec<u8>> {
+pub type Result<T, F = Error> = std::result::Result<T, F>;
+
+#[derive(Debug)]
+pub struct Error {
+ pub file_name: Option<String>,
+ pub line_number: Option<usize>,
+ pub token: Option<String>,
+ pub message: String,
+}
+
+impl Error {
+ fn new(
+ file_name: Option<&str>,
+ line_number: Option<usize>,
+ token: Option<&str>,
+ message: String,
+ ) -> Error {
+ Error {
+ file_name: file_name.map(String::from),
+ line_number,
+ token: token.map(String::from),
+ message,
+ }
+ }
+}
+
+impl StdError for Error {}
+
+impl Display for Error {
+ fn fmt(&self, f: &mut Formatter) -> FmtResult {
+ match (self.file_name.as_ref(), self.line_number) {
+ (Some(ref file_name), Some(line_number)) => write!(f, "{file_name}:{line_number}: ")?,
+ (Some(ref file_name), None) => write!(f, "{file_name}: ")?,
+ (None, Some(line_number)) => write!(f, "line {line_number}: ")?,
+ (None, None) => (),
+ }
+ if let Some(ref token) = self.token {
+ write!(f, "at '{token}': ")?;
+ }
+ write!(f, "{}", self.message)
+ }
+}
+
+pub fn sack(input: &str, input_file_name: Option<&str>, endian: Endian) -> Result<Vec<u8>> {
let mut symbol_table = HashMap::new();
- let output = _sack(input, endian, &mut symbol_table)?;
+ let output = _sack(input, input_file_name, endian, &mut symbol_table)?;
let output = if !symbol_table.is_empty() {
+ for (k, v) in symbol_table.iter() {
+ println!("{k} => {v:?}");
+ }
for (k, v) in symbol_table.iter() {
if v.is_none() {
- return Err(anyhow!("label {k} used but never defined"));
+ Err(Error::new(
+ input_file_name,
+ None,
+ None,
+ format!("label {k} used but never defined"),
+ ))?
}
}
- _sack(input, endian, &mut symbol_table)?
+ _sack(input, input_file_name, endian, &mut symbol_table)?
} else {
output
};
fn _sack(
input: &str,
+ input_file_name: Option<&str>,
endian: Endian,
symbol_table: &mut HashMap<String, Option<u32>>,
) -> Result<Vec<u8>> {
- let mut lexer = Lexer::new(input, endian)?;
+ let mut lexer = Lexer::new(input, input_file_name, endian)?;
let mut output = Vec::new();
while parse_data_item(&mut lexer, &mut output, symbol_table)? {}
Ok(output)
let initial_len = output.len();
match lexer.take()? {
- Token::Integer(integer) => output.extend_from_slice(&lexer.endian.to_bytes(integer)),
+ Token::Integer(integer) => {
+ if let Ok(integer) = TryInto::<i32>::try_into(integer) {
+ output.extend_from_slice(&lexer.endian.to_bytes(integer));
+ } else if let Ok(integer) = TryInto::<u32>::try_into(integer) {
+ output.extend_from_slice(&lexer.endian.to_bytes(integer));
+ } else {
+ Err(lexer.error(format!(
+ "{integer} is not in the valid range [{},{}]",
+ i32::min_value(),
+ u32::max_value()
+ )))?;
+ };
+ }
Token::Float(float) => output.extend_from_slice(&lexer.endian.to_bytes(float.0)),
Token::PcSysmis => {
output.extend_from_slice(&[0xf5, 0x1e, 0x26, 0x02, 0x8a, 0x8c, 0xed, 0xff])
Token::I64 => put_integers::<i64, 8>(lexer, "i64", output)?,
Token::String(string) => output.extend_from_slice(string.as_bytes()),
Token::S(size) => {
- let Some(Token::String(ref string)) = lexer.token else {
- return Err(anyhow!("string expected after 's{size}'"));
+ let Some((Token::String(ref string), _)) = lexer.token else {
+ Err(lexer.error(format!("string expected after 's{size}'")))?
};
let len = string.len();
if len > size {
- return Err(anyhow!(
+ Err(lexer.error(format!(
"{len}-byte string is longer than pad length {size}"
- ));
+ )))?
}
output.extend_from_slice(string.as_bytes());
output.extend(repeat(b' ').take(size - len));
lexer.get()?;
}
Token::LParen => {
- while lexer.token != Some(Token::RParen) {
+ while !matches!(lexer.token, Some((Token::RParen, _))) {
parse_data_item(lexer, output, symbol_table)?;
}
lexer.get()?;
Token::Count => put_counted_items::<u32, 4>(lexer, "COUNT", output, symbol_table)?,
Token::Count8 => put_counted_items::<u8, 1>(lexer, "COUNT8", output, symbol_table)?,
Token::Hex => {
- let Some(Token::String(ref string)) = lexer.token else {
- return Err(anyhow!("string expected after 'hex'"));
+ let Some((Token::String(ref string), _)) = lexer.token else {
+ Err(lexer.error(String::from("string expected after 'hex'")))?
};
- let mut i = string.chars();
+ let mut string = &string[..];
loop {
+ string = string.trim_start();
+ if string.is_empty() {
+ break;
+ };
+
+ let mut i = string.chars();
let Some(c0) = i.next() else { return Ok(true) };
let Some(c1) = i.next() else {
- return Err(anyhow!("hex string has odd number of characters"));
+ Err(lexer.error(String::from("hex string has odd number of characters")))?
};
+
let (Some(digit0), Some(digit1)) = (c0.to_digit(16), c1.to_digit(16)) else {
- return Err(anyhow!("invalid digit in hex string"));
+ Err(lexer.error(String::from("invalid digit in hex string")))?
};
let byte = digit0 * 16 + digit1;
output.push(byte as u8);
+
+ string = i.as_str();
}
+ lexer.get()?;
}
Token::Label(name) => {
+ println!("define {name}");
let value = output.len() as u32;
- match symbol_table.entry(name) {
+ match symbol_table.entry(name.clone()) {
Entry::Vacant(v) => {
v.insert(Some(value));
}
- Entry::Occupied(o) => {
- if let Some(v) = o.get() {
- if *v != value {
- return Err(anyhow!("syntax error"));
+ Entry::Occupied(mut o) => {
+ match o.get() {
+ Some(v) => {
+ if *v != value {
+ Err(lexer.error(format!("{name}: can't redefine label for offset {:#x} with offset {:#x}", *v, value)))?
+ }
}
+ None => drop(o.insert(Some(value))),
}
}
};
+ return Ok(true);
}
Token::At(name) => {
- let mut value = symbol_table.entry(name).or_insert(None).unwrap_or(0);
- lexer.get()?;
+ let mut value = *symbol_table.entry(name.clone()).or_insert(None);
loop {
let plus = match lexer.token {
- Some(Token::Plus) => true,
- Some(Token::Minus) => false,
+ Some((Token::Plus, _)) => true,
+ Some((Token::Minus, _)) => false,
_ => break,
};
lexer.get()?;
let operand = match lexer.token {
- Some(Token::At(ref name)) => if let Some(value) = symbol_table.get(name) {
- *value
- } else {
- symbol_table.insert(name.clone(), None);
- None
+ Some((Token::At(ref name), _)) => {
+ *symbol_table.entry(name.clone()).or_insert(None)
}
- .unwrap_or(0),
- Some(Token::Integer(integer)) => integer
- .try_into()
- .map_err(|msg| anyhow!("bad offset literal ({msg})"))?,
- _ => return Err(anyhow!("expecting @label or integer literal")),
+ Some((Token::Integer(integer), _)) => Some(
+ integer
+ .try_into()
+ .map_err(|msg| lexer.error(format!("bad offset literal ({msg})")))?,
+ ),
+ _ => Err(lexer.error(String::from("expecting @label or integer literal")))?,
};
lexer.get()?;
- value = if plus {
- value.checked_add(operand)
- } else {
- value.checked_sub(operand)
- }
- .ok_or_else(|| anyhow!("overflow in offset arithmetic"))?;
+ value = match (value, operand) {
+ (Some(a), Some(b)) => Some(
+ if plus {
+ a.checked_add(b)
+ } else {
+ a.checked_sub(b)
+ }
+ .ok_or_else(|| {
+ lexer.error(String::from("overflow in offset arithmetic"))
+ })?,
+ ),
+ _ => None,
+ };
}
+ let value = value.unwrap_or(0);
output.extend_from_slice(&lexer.endian.to_bytes(value));
}
_ => (),
};
- if lexer.token == Some(Token::Asterisk) {
+ if let Some((Token::Asterisk, _)) = lexer.token {
lexer.get()?;
let Token::Integer(count) = lexer.take()? else {
- return Err(anyhow!("positive integer expected after '*'"));
+ Err(lexer.error(String::from("positive integer expected after '*'")))?
};
if count < 1 {
- return Err(anyhow!("positive integer expected after '*'"));
+ Err(lexer.error(String::from("positive integer expected after '*'")))?
};
let final_len = output.len();
for _ in 1..count {
}
}
match lexer.token {
- Some(Token::Semicolon) => {
+ Some((Token::Semicolon, _)) => {
lexer.get()?;
}
- Some(Token::RParen) => (),
- _ => return Err(anyhow!("';' expected")),
+ Some((Token::RParen, _)) => (),
+ _ => Err(lexer.error(String::from("';' expected")))?,
}
Ok(true)
}
{
let old_size = output.len();
output.extend_from_slice(&lexer.endian.to_bytes(T::zero()));
- if lexer.token != Some(Token::LParen) {
- return Err(anyhow!("'(' expected after '{name}'"));
+ let start = output.len();
+ if !matches!(lexer.token, Some((Token::LParen, _))) {
+ Err(lexer.error(format!("'(' expected after '{name}'")))?
}
lexer.get()?;
- while lexer.token != Some(Token::RParen) {
+ while !matches!(lexer.token, Some((Token::RParen, _))) {
parse_data_item(lexer, output, symbol_table)?;
}
lexer.get()?;
- let delta = output.len() - old_size;
+ let delta = output.len() - start;
let Ok(delta): Result<T, _> = delta.try_into() else {
- return Err(anyhow!("{delta} bytes is too much for '{name}'"));
+ Err(lexer.error(format!("{delta} bytes is too much for '{name}'")))?
};
let dest = &mut output[old_size..old_size + N];
dest.copy_from_slice(&lexer.endian.to_bytes(delta));
T: Bounded + Display + TryFrom<i64> + Copy,
Endian: ToBytes<T, N>,
{
+ println!("put_integers {:?}", lexer.token);
let mut n = 0;
while let Some(integer) = lexer.take_if(|t| match t {
Token::Integer(integer) => Some(*integer),
_ => None,
})? {
+ println!("got integer {integer}");
let Ok(integer) = integer.try_into() else {
- return Err(anyhow!(
+ Err(lexer.error(format!(
"{integer} is not in the valid range [{},{}]",
T::min_value(),
T::max_value()
- ));
+ )))?
};
output.extend_from_slice(&lexer.endian.to_bytes(integer));
n += 1;
}
+ println!("put_integers {:?} {n}", lexer.token);
if n == 0 {
- return Err(anyhow!("integer expected after '{name}'"));
+ Err(lexer.error(format!("integer expected after '{name}'")))?
}
Ok(())
}
-#[derive(PartialEq, Eq, Clone)]
+#[derive(PartialEq, Eq, Clone, Debug)]
enum Token {
Integer(i64),
Float(OrderedFloat<f64>),
}
struct Lexer<'a> {
- iter: Peekable<Chars<'a>>,
- token: Option<Token>,
+ input: &'a str,
+ token: Option<(Token, &'a str)>,
+ input_file_name: Option<&'a str>,
line_number: usize,
endian: Endian,
}
+fn skip_comments(mut s: &str) -> (&str, usize) {
+ let mut n_newlines = 0;
+ let s = loop {
+ s = s.trim_start_matches([' ', '\t', '\r', '<', '>']);
+ if let Some(remainder) = s.strip_prefix('#') {
+ let Some((_, remainder)) = remainder.split_once('\n') else {
+ break "";
+ };
+ s = remainder;
+ n_newlines += 1;
+ } else if let Some(remainder) = s.strip_prefix('\n') {
+ s = remainder;
+ n_newlines += 1;
+ } else {
+ break s;
+ }
+ };
+ (s, n_newlines)
+}
+
impl<'a> Lexer<'a> {
- fn new(input: &'a str, endian: Endian) -> Result<Lexer<'a>> {
+ fn new(input: &'a str, input_file_name: Option<&'a str>, endian: Endian) -> Result<Lexer<'a>> {
let mut lexer = Lexer {
- iter: input.chars().peekable(),
+ input,
token: None,
+ input_file_name,
line_number: 1,
endian,
};
- lexer.next()?;
+ lexer.token = lexer.next()?;
Ok(lexer)
}
+ fn error(&self, message: String) -> Error {
+ let repr = self.token.as_ref().map(|(_, repr)| *repr);
+ Error::new(self.input_file_name, Some(self.line_number), repr, message)
+ }
fn take(&mut self) -> Result<Token> {
let Some(token) = self.token.take() else {
- return Err(anyhow!("unexpected end of input"));
+ Err(self.error(String::from("unexpected end of input")))?
};
self.token = self.next()?;
- Ok(token)
+ Ok(token.0)
}
fn take_if<F, T>(&mut self, condition: F) -> Result<Option<T>>
where
let Some(ref token) = self.token else {
return Ok(None);
};
- match condition(token) {
+ match condition(&token.0) {
Some(value) => {
self.token = self.next()?;
Ok(Some(value))
}
fn get(&mut self) -> Result<Option<&Token>> {
if self.token.is_none() {
- Err(anyhow!("unexpected end of input"))
+ Err(self.error(String::from("unexpected end of input")))?
} else {
self.token = self.next()?;
- Ok((&self.token).into())
+ match self.token {
+ Some((ref token, _)) => Ok(Some(token)),
+ None => Ok(None),
+ }
}
}
- fn next(&mut self) -> Result<Option<Token>> {
+ fn next(&mut self) -> Result<Option<(Token, &'a str)>> {
// Get the first character of the token, skipping past white space and
// comments.
- let c = loop {
- let Some(c) = self.iter.next() else {
- return Ok(None);
- };
- let c = if c == '#' {
- loop {
- match self.iter.next() {
- None => return Ok(None),
- Some('\n') => break,
- _ => (),
- }
- }
- '\n'
- } else {
- c
- };
- if c == '\n' {
- self.line_number += 1
- } else if !c.is_whitespace() && c != '<' && c != '>' {
- break c;
- }
- };
+ let (s, n_newlines) = skip_comments(self.input);
+ self.line_number += n_newlines;
+ self.input = s;
- let token = match c {
+ let start = s;
+ let mut iter = s.chars();
+ let Some(c) = iter.next() else {
+ return Ok(None);
+ };
+ let (token, rest) = match c {
c if c.is_ascii_digit() || c == '-' => {
- let mut s = String::from(c);
- while let Some(c) = self
- .iter
- .next_if(|&c| c.is_ascii_digit() || c.is_alphabetic() || c == '.')
- {
- s.push(c);
- }
-
- if s == "-" {
+ let len = s
+ .find(|c: char| {
+ !(c.is_ascii_digit() || c.is_alphabetic() || c == '.' || c == '-')
+ })
+ .unwrap_or_else(|| s.len());
+ let (number, rest) = s.split_at(len);
+ let token = if number == "-" {
Token::Minus
- } else if !s.contains('.') {
- Token::Integer(
- s.parse()
- .map_err(|msg| anyhow!("bad integer literal '{s}' ({msg})"))?,
- )
+ } else if let Some(digits) = number.strip_prefix("0x") {
+ Token::Integer(i64::from_str_radix(digits, 16).map_err(|msg| {
+ self.error(format!("bad integer literal '{number}' ({msg})"))
+ })?)
+ } else if !number.contains('.') {
+ Token::Integer(number.parse().map_err(|msg| {
+ self.error(format!("bad integer literal '{number}' ({msg})"))
+ })?)
} else {
- Token::Float(
- s.parse()
- .map_err(|msg| anyhow!("bad float literal '{s}' ({msg})"))?,
- )
- }
+ Token::Float(number.parse().map_err(|msg| {
+ self.error(format!("bad float literal '{number}' ({msg})"))
+ })?)
+ };
+ (token, rest)
}
'"' => {
- let mut s = String::from(c);
- loop {
- match self.iter.next() {
- None => return Err(anyhow!("end-of-file inside string")),
- Some('\n') => return Err(anyhow!("new-line inside string")),
- Some('"') => break,
- Some(c) => s.push(c),
- }
- }
- Token::String(s)
+ let s = iter.as_str();
+ let Some(len) = s.find(['\n', '"']) else {
+ Err(self.error(String::from("end-of-file inside string")))?
+ };
+ let (string, rest) = s.split_at(len);
+ let Some(rest) = rest.strip_prefix('"') else {
+ Err(self.error(format!("new-line inside string ({string}...{rest})")))?
+ };
+ (Token::String(string.into()), rest)
}
- ';' => Token::Semicolon,
- '*' => Token::Asterisk,
- '+' => Token::Plus,
- '(' => Token::LParen,
- ')' => Token::RParen,
+ ';' => (Token::Semicolon, iter.as_str()),
+ '*' => (Token::Asterisk, iter.as_str()),
+ '+' => (Token::Plus, iter.as_str()),
+ '(' => (Token::LParen, iter.as_str()),
+ ')' => (Token::RParen, iter.as_str()),
c if c.is_alphabetic() || c == '@' || c == '_' => {
- let mut s = String::from(c);
- while let Some(c) = self
- .iter
- .next_if(|&c| c.is_ascii_digit() || c.is_alphabetic() || c == '.' || c == '_')
- {
- s.push(c);
- }
- if self.iter.next_if_eq(&':').is_some() {
- Token::Label(s)
- } else if s.starts_with('@') {
- Token::At(s)
+ let len = s
+ .find(|c: char| {
+ !(c.is_ascii_digit()
+ || c.is_alphabetic()
+ || c == '@'
+ || c == '.'
+ || c == '_')
+ })
+ .unwrap_or_else(|| s.len());
+ let (s, rest) = s.split_at(len);
+ if let Some(rest) = rest.strip_prefix(':') {
+ (Token::Label(s.into()), rest)
+ } else if let Some(name) = s.strip_prefix('@') {
+ (Token::At(name.into()), rest)
} else if let Some(count) = s.strip_prefix('s') {
- Token::S(
- count
- .parse()
- .map_err(|msg| anyhow!("bad counted string '{s}' ({msg})"))?,
- )
+ let token =
+ Token::S(count.parse().map_err(|msg| {
+ self.error(format!("bad counted string '{s}' ({msg})"))
+ })?);
+ (token, rest)
} else {
- match &s[..] {
+ let token = match &s[..] {
"i8" => Token::I8,
"i16" => Token::I16,
"i64" => Token::I64,
"COUNT" => Token::Count,
"COUNT8" => Token::Count8,
"hex" => Token::Hex,
- _ => return Err(anyhow!("invalid token '{s}'")),
- }
+ _ => Err(self.error(format!("invalid token '{s}'")))?,
+ };
+ (token, rest)
}
}
- _ => return Err(anyhow!("invalid input byte '{c}'")),
+ _ => Err(self.error(format!("invalid input byte '{c}'")))?,
};
- Ok(Some(token))
+ self.input = rest;
+ let repr = &start[..start.len() - rest.len()];
+ println!("{token:?} {repr}");
+ Ok(Some((token, repr)))
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use crate::endian::Endian;
+ use crate::sack::sack;
+ use anyhow::Result;
+ use hexplay::HexView;
+
+ #[test]
+ fn basic_sack() -> Result<()> {
+ let input = r#"
+"$FL2"; s60 "$(#) SPSS DATA FILE PSPP synthetic test file";
+2; # Layout code
+28; # Nominal case size
+0; # Not compressed
+0; # Not weighted
+1; # 1 case.
+100.0; # Bias.
+"01 Jan 11"; "20:53:52";
+"PSPP synthetic test file: "; i8 244; i8 245; i8 246; i8 248; s34 "";
+i8 0 *3;
+"#;
+ let output = sack(input, None, Endian::Big)?;
+ HexView::new(&output).print()?;
+ Ok(())
+ }
+
+ #[test]
+ fn pcp_sack() -> Result<()> {
+ let input = r#"
+# File header.
+2; 0;
+@MAIN; @MAIN_END - @MAIN;
+@VARS; @VARS_END - @VARS;
+@LABELS; @LABELS_END - @LABELS;
+@DATA; @DATA_END - @DATA;
+(0; 0) * 11;
+i8 0 * 128;
+
+MAIN:
+ i16 1; # Fixed.
+ s62 "PCSPSS PSPP synthetic test product";
+ PCSYSMIS;
+ 0; 0; i16 1; # Fixed.
+ i16 0;
+ i16 15;
+ 1;
+ i16 0; # Fixed.
+ 1;
+ s8 "11/28/14";
+ s8 "15:11:00";
+ s64 "PSPP synthetic test file";
+MAIN_END:
+
+VARS:
+ 0; 0; 0; 0x050800; s8 "$CASENUM"; PCSYSMIS;
+ 0; 0; 0; 0x010800; s8 "$DATE"; PCSYSMIS;
+ 0; 0; 0; 0x050802; s8 "$WEIGHT"; PCSYSMIS;
+
+ # Numeric variable, no label or missing values.
+ 0; 0; 0; 0x050800; s8 "NUM1"; PCSYSMIS;
+
+ # Numeric variable, variable label.
+ 0; 0; @NUM2_LABEL - @LABELS_OFS; 0x050800; s8 "NUM2"; PCSYSMIS;
+
+ # Numeric variable with missing value.
+ 0; 0; 0; 0x050800; s8 "NUM3"; 1.0;
+
+ # Numeric variable, variable label and missing value.
+ 0; 0; @NUM4_LABEL - @LABELS_OFS; 0x050800; s8 "NUM4"; 2.0;
+
+ # String variable, no label or missing values.
+ 0; 0; 0; 0x010800; s8 "STR1"; PCSYSMIS;
+
+ # String variable, variable label.
+ 0; 0; @STR2_LABEL - @LABELS_OFS; 0x010400; s8 "STR2"; PCSYSMIS;
+
+ # String variable with missing value.
+ 0; 0; 0; 0x010500; s8 "STR3"; s8 "MISS";
+
+ # String variable, variable label and missing value.
+ 0; 0; @STR4_LABEL - @LABELS_OFS; 0x010100; s8 "STR4"; s8 "OTHR";
+
+ # Long string variable
+ 0; 0; 0; 0x010b00; s8 "STR5"; PCSYSMIS;
+ 0 * 8;
+
+ # Long string variable with variable label
+ 0; 0; @STR6_LABEL - @LABELS_OFS; 0x010b00; s8 "STR6"; PCSYSMIS;
+ 0 * 8;
+VARS_END:
+
+LABELS:
+ 3; i8 0 0 0; LABELS_OFS: i8 0;
+ NUM2_LABEL: COUNT8("Numeric variable 2's label");
+ NUM4_LABEL: COUNT8("Another numeric variable label");
+ STR2_LABEL: COUNT8("STR2's variable label");
+ STR4_LABEL: COUNT8("STR4's variable label");
+ STR6_LABEL: COUNT8("Another string variable's label");
+LABELS_END:
+
+DATA:
+ 0.0; "11/28/14"; 1.0;
+ 0.0; 1.0; 2.0; PCSYSMIS; s8 "abcdefgh"; s8 "ijkl"; s8 "mnopq"; s8 "r";
+ s16 "stuvwxyzAB"; s16 "CDEFGHIJKLM";
+DATA_END:
+"#;
+ let output = sack(input, None, Endian::Big)?;
+ HexView::new(&output).print()?;
+ Ok(())
}
}