printf: scaffolding for C99 hex float

src/printf/tokenize/num_format/format_field.rs

@@ -4,6 +4,7 @@
 pub enum FieldType {
     Strf,
     Floatf,
+    CninetyNineHexFloatf,
     Scif,
     Decf,
     Intf,

src/printf/tokenize/num_format/formatters/base_conv/mod.rs

@@ -1,5 +1,5 @@
 pub fn arrnum_int_mult(
-    arrnum : &Vec<u8>,
+    arr_num : &Vec<u8>,
     basenum : u8,
     base_ten_int_fact : u8 
     ) -> Vec<u8> {
@@ -10,7 +10,7 @@ pub fn arrnum_int_mult(
     let base : u16 = basenum as u16;
      
     let mut ret_rev : Vec<u8> = Vec::new();
-    let mut it = arrnum.iter().rev();
+    let mut it = arr_num.iter().rev();
     loop {
         let i = it.next();
         match i {
@@ -35,41 +35,119 @@ pub fn arrnum_int_mult(
     ret
 }
 
-pub struct Remainder {    
-    position : usize,
-    replace : Option<u8>
+pub struct Remainder<'a> {    
+    pub position: usize,
+    pub replace: Vec<u8>,
+    pub arr_num: &'a Vec<u8>
 }
 
-pub struct DivOut {
-    quotient : u8,
-    remainder: Remainder
+pub struct DivOut<'a> {
+    pub quotient: u8,
+    pub remainder: Remainder<'a>
 }
 
-pub fn arrnum_int_div(
-    arrnum : &Vec<u8>,
-    basenum : u8,
-    base_ten_int_divisor : u8,
-    rem_in : Remainder
-        ) -> DivOut  {
+pub fn arrnum_int_div_step<'a>(
+    rem_in: Remainder<'a>,
+    radix_in: u8,
+    base_ten_int_divisor: u8,
+    after_decimal: bool
+        ) -> DivOut<'a>  {
 
     let mut rem_out = Remainder {
         position: rem_in.position,
-        replace : None
+        replace: Vec::new(),
+        arr_num: rem_in.arr_num
     };
 
-    let mut bufferval : u16 = 0;
-    let base : u16 = basenum as u16;
-    let divisor : u16 = base_ten_int_divisor as u16;
+    let mut bufferval: u16 = 0;
+    let base: u16 = radix_in as u16;
+    let divisor: u16 = base_ten_int_divisor as u16;
+    let mut traversed = 0;
 
     let mut quotient = 0;
-    let mut u_cur : Option<&u8> = Some(match rem_in.replace {
-        Some(ref u) => { u }
-        None => { &arrnum[rem_in.position] }
-    });
+    let refd_vals = &rem_in.arr_num[rem_in.position+rem_in.replace.len()..];
+    let mut it_replace = rem_in.replace.iter();
+    let mut it_f = refd_vals.iter();
+    loop {
+        let u = match it_replace.next() {
+            Some(u_rep) => { u_rep.clone() as u16 }
+            None => {
+                match it_f.next() {
+                    Some(u_orig) => {
+                        u_orig.clone() as u16
+                    }
+                    None => {
+                        if !after_decimal {
+                            break;
+                        }
+                        0
+                    }
+                }
+            }
+        };
+        traversed += 1;
+        bufferval += u;
+        if bufferval > divisor {
+            while bufferval >= divisor {
+                quotient+=1;
+                bufferval -= divisor;
+            }
+            rem_out.replace = if bufferval == 0 {
+                Vec::new()
+            } else {
+                let remainder_as_arrnum = unsigned_to_arrnum(bufferval);
+                let remainder_as_base_arrnum = base_conv_vec(
+                    &remainder_as_arrnum,
+                    10,
+                    radix_in
+                );
+                remainder_as_base_arrnum
+            };
+            rem_out.position += 1+(traversed - rem_out.replace.len());
+            break;
+        } else {
+            bufferval *= base;            
+        }
+    }
+    DivOut { quotient: quotient, remainder: rem_out }
+}
+/*
+pub struct ArrFloat {
+    pub leading_zeros: u8,
+    pub values: Vec<u8>,
+    pub basenum: u8
+}
 
-    let str_f = &arrnum[rem_in.position+1..];
-    let mut it_f = str_f.iter();
-    loop {        
+pub struct ArrFloatDivOut {
+    pub quotient: u8,
+    pub remainder: ArrFloat
+}
+
+pub fn arrfloat_int_div(
+    arrfloat_in : &ArrFloat,
+    base_ten_int_divisor : u8,
+    precision : u16
+) -> DivOut  {
+
+    let mut remainder = ArrFloat {
+        basenum: arrfloat_in.basenum,
+        leading_zeros: arrfloat_in.leading_zeroes,
+        values: Vec<u8>::new()
+    }
+    let mut quotient = 0;
+    
+    let mut bufferval : u16 = 0;
+    let base : u16 = arrfloat_in.basenum as u16;
+    let divisor : u16 = base_ten_int_divisor as u16;
+
+    let mut it_f = arrfloat_in.values.iter();
+    let mut position = 0 + arrfloat_in.leading_zeroes as u16;
+    let mut at_end = false;
+    while position< precision {
+        let next_digit = match it_f.next() {
+            Some(c) => {}
+            None => { 0 }
+        }
         match u_cur {
             Some(u) => {
                 bufferval += u.clone() as u16;
@@ -95,9 +173,9 @@ pub fn arrnum_int_div(
         u_cur = it_f.next().clone();
         rem_out.position+=1;
     }
-    DivOut { quotient: quotient, remainder: rem_out }
+    ArrFloatDivOut { quotient: quotient, remainder: remainder }
 }
-
+*/
 pub fn arrnum_int_add(
     arrnum : &Vec<u8>,
     basenum : u8,
@@ -153,7 +231,22 @@ pub fn base_conv_vec(
     result
 }
 
+pub fn unsigned_to_arrnum(
+    src : u16
+) -> Vec<u8> {
+    let mut result : Vec<u8> = Vec::new();
+    let mut src_tmp : u16 = src.clone();
+    while src_tmp > 0 {
+        result.push((src_tmp % 10) as u8);
+        src_tmp /= 10;
+    }
+    result.reverse();
+    result
+}
 
+
+//temporary needs-improvement-function
+#[allow(unused_variables)]
 pub fn base_conv_float(
     src : &Vec<u8>,
     radix_src : u8,
@@ -165,11 +258,10 @@ pub fn base_conv_float(
     // of how it would work.
     let mut result : Vec<u8> = Vec::new();
     result.push(0);
-    let mut factor : f64 = radix_dest as f64;
+    let mut factor : f64 = 1.;
     let radix_src_float : f64 = radix_src as f64;
     let mut i = 0;
     let mut r :f64 = 0 as f64;
-    factor /= 10.;
     for u in src {
         if i > 15 { break; }
         i+=1;
@@ -271,3 +363,4 @@ impl RadixDef for RadixHex {
     }
 }
 
+mod tests;

src/printf/tokenize/num_format/formatters/base_conv/tests.rs

@@ -0,0 +1,64 @@
+#[cfg(test)]
+
+use super::*;
+
+#[test]
+fn test_arrnum_int_mult() {
+    //(in base 10) 12 * 4 = 48
+    let factor : Vec<u8> = vec!(1, 2);
+    let base_num = 10;
+    let base_ten_int_fact : u8 = 4;
+    let should_output : Vec<u8> = vec![4, 8];
+    
+    let product = arrnum_int_mult(&factor,
+                                         base_num, base_ten_int_fact);
+    assert!(product == should_output);
+}
+
+#[test]
+fn test_arrnum_int_non_base_10() {
+    //(in base 3)
+    // 5 * 4 = 20
+    let factor : Vec<u8> = vec![1, 2];
+    let base_num = 3;
+    let base_ten_int_fact : u8 = 4;
+    let should_output : Vec<u8> = vec![2,0,2];
+    
+    let product = arrnum_int_mult(&factor,
+                                         base_num, base_ten_int_fact);
+    assert!(product == should_output);
+}
+
+#[test]
+fn test_arrnum_int_div_shortcircuit() {
+    //(
+    let arrnum : Vec<u8> = vec![5,5,5,5,0];
+    let base_num = 10;
+    let base_ten_int_divisor : u8 = 41;
+    let remainder_passed_in = Remainder {
+        position : 1,
+        replace : vec![1,3],
+        arr_num : &arrnum
+    };
+
+    //the "replace" should mean the number being divided
+    // is 1350, the first time you can get 41 to go into
+    // 1350, its at 135, where you can get a quotient of
+    // 3 and a remainder of 12;
+
+    let quotient_should_be : u8 = 3;
+    let remainder_position_should_be : usize = 3;
+    let remainder_replace_should_be = vec![1, 2];
+    
+    let result = arrnum_int_div_step(remainder_passed_in,
+                                            base_num,
+                                            base_ten_int_divisor,
+                                            false
+                                            
+    );
+    assert!(quotient_should_be == result.quotient);
+    assert!(remainder_position_should_be ==
+            result.remainder.position);
+    assert!(remainder_replace_should_be ==
+            result.remainder.replace);                
+}    

src/printf/tokenize/num_format/formatters/cninetyninehexfloatf.rs

@@ -0,0 +1,146 @@
+//! formatter for %a %F C99 Hex-floating-point subs
+use super::super::format_field::FormatField;
+use super::super::formatter::{InPrefix,FormatPrimitive,Formatter};
+use super::float_common::{FloatAnalysis,
+                          primitive_to_str_common};
+use super::base_conv;
+use super::base_conv::{RadixDef};
+
+
+pub struct CninetyNineHexFloatf {
+    as_num : f64
+}
+impl CninetyNineHexFloatf {
+    pub fn new() -> CninetyNineHexFloatf {
+        CninetyNineHexFloatf { as_num: 0.0 }
+    }
+}
+
+impl Formatter for CninetyNineHexFloatf {
+    fn get_primitive(
+        &self,
+        field : &FormatField,
+        inprefix : &InPrefix,
+        str_in : &str
+            ) -> Option<FormatPrimitive> {
+        let second_field = field.second_field.unwrap_or(6)+1;
+        let analysis = FloatAnalysis::analyze(
+            &str_in,
+            inprefix,
+            Some(second_field as usize),
+            None,
+            true);
+        let f = get_primitive_hex(
+            inprefix,
+            &str_in[inprefix.offset..],
+            &analysis,
+            second_field as usize,
+            *field.field_char == 'A');
+        Some(f)
+    }
+    fn primitive_to_str(
+        &self,
+        prim: &FormatPrimitive,
+        field: FormatField) -> String {
+        primitive_to_str_common(
+            prim,
+            &field
+            )
+    }
+}
+
+//c99 hex has unique requirements of all floating point subs in pretty much every part of building a primitive, from prefix and suffix to need for base conversion (in all other cases if you don't have decimal you must have decimal, here it's the other way around)
+
+// on the todo list is to have a trait for get_primitive that is implemented by each float formatter and can override a default. when that happens we can take the parts of get_primitive_dec specific to dec and spin them out to their own functions that can be overriden.
+#[allow(unused_variables)]
+#[allow(unused_assignments)]
+fn get_primitive_hex(
+    inprefix : &InPrefix,
+    str_in : &str,
+    analysis : &FloatAnalysis,
+    last_dec_place : usize,
+    capitalized : bool
+) -> FormatPrimitive {
+   
+    let mut f : FormatPrimitive = Default::default();
+    f.prefix = Some(String::from(
+        if inprefix.sign == -1 { "-0x" } else { "0x" }));
+
+    // assign the digits before and after the decimal points
+    // to separate slices. If no digits after decimal point,
+    // assign 0
+    let (mut first_segment_raw, second_segment_raw) =
+        match analysis.decimal_pos {
+            Some(pos) => {
+                (&str_in[..pos], &str_in[pos+1..])
+            },
+            None => { (&str_in[..], "0") }
+        };
+    if first_segment_raw.len() == 0 {
+        first_segment_raw = "0";
+    }
+    // convert to string, hexifying if input is in dec.
+    /*let (first_segment, second_segment) =
+        match inprefix.radix_in {
+            Base::Ten => {
+                (to_hex(first_segment_raw, true),
+                 to_hex(second_segment_raw, false))
+            }
+            _ => {
+                (String::from(first_segment_raw),
+                 String::from(second_segment_raw))
+            }
+        };
+    
+    
+    f.pre_decimal = Some(first_segment);
+    f.post_decimal = Some(second_segment);
+     */
+    //TODO actual conversion, make sure to get back mantissa.
+    // for hex to hex, it's really just a matter of moving the
+    // decimal point and calculating the mantissa by its initial
+    // position and its moves, with every position counting for
+    // the addition or subtraction of 4 (2**4, because 4 bits in a hex digit)
+    // to the exponent.
+    // decimal's going to be a little more complicated. correct simulation
+    // of glibc will require after-decimal division to a specified precisino.
+    // the difficult part of this (arrnum_int_div_step) is already implemented.
+
+    // the hex float name may be a bit misleading in terms of how to go about the
+    // conversion. The best way to do it is to just convert the floatnum
+    // directly to base 2 and then at the end translate back to hex.
+    let mantissa=0;
+    f.suffix = Some({
+        let ind = if capitalized { "P" } else { "p" };
+        if mantissa >=0 {
+            format!("{}+{}", ind, mantissa)
+        } else {
+            format!("{}{}", ind, mantissa)
+        }
+    });
+    f
+}
+
+fn to_hex(
+    src: &str,
+    before_decimal: bool
+        ) -> String {
+    let rten = base_conv::RadixTen;    
+    let rhex = base_conv::RadixHex;
+    if before_decimal {
+        base_conv::base_conv_str(src, &rten, &rhex)
+    } else {
+        let as_arrnum_ten =base_conv::str_to_arrnum(src, &rten);
+        let s = format!("{}", base_conv::base_conv_float(
+            &as_arrnum_ten,
+            rten.get_max(),
+            rhex.get_max()
+                ));
+        if s.len() > 2 {
+            String::from(&s[2..])
+        } else {
+            //zero
+            s
+        }
+    }
+}

src/printf/tokenize/num_format/formatters/decf.rs

@@ -32,12 +32,14 @@ impl Formatter for Decf {
         str_in : &str
             ) -> Option<FormatPrimitive> {
         let second_field = field.second_field.unwrap_or(6)+1;
+        //default to scif interp. so as to not truncate input vals
+        //(that would be displayed in scif) based on relation to decimal place
         let analysis = FloatAnalysis::analyze(
             str_in,
             inprefix,
             Some(second_field as usize+1),            
-            None
-                );
+            None,
+            false);
         let mut f_sci = get_primitive_dec(
             inprefix,
             &str_in[inprefix.offset..],

src/printf/tokenize/num_format/formatters/float_common.rs

@@ -13,12 +13,37 @@ pub struct FloatAnalysis {
     pub decimal_pos: Option<usize>,
     pub follow: Option<char>
 }
+fn has_enough_digits(
+    hex_input: bool,
+    hex_output: bool,
+    string_position: usize,
+    starting_position: usize,
+    limit: usize,
+) -> bool {
+    //-1s are for rounding
+    if hex_output {
+        if hex_input {
+            ((string_position-1) - starting_position >= limit)
+        } else {
+            false //undecidable without converting
+        }
+    } else {
+        if hex_input {
+            ((((string_position-1) - starting_position)*9)/8 >= limit)
+        } else {
+            ((string_position-1) - starting_position >= limit)
+        }                            
+    }
+    
+}
+
 impl FloatAnalysis {
     pub fn analyze(
         str_in: &str,
         inprefix: &InPrefix,
         max_sd_opt: Option<usize>,
         max_after_dec_opt: Option<usize>,
+        hex_output: bool
         ) -> FloatAnalysis {
         // this fn assumes
         // the input string
@@ -29,20 +54,26 @@ impl FloatAnalysis {
             decimal_pos: None,
             follow: None
         };
+        let hex_input = match inprefix.radix_in {
+            Base::Hex => { true }
+            Base::Ten => { false }
+            Base::Octal => { panic!("this should never happen: floats should never receive octal input"); }
+        };
         let mut i=0;
+        let mut pos_before_first_nonzero_after_decimal : Option<usize> = None;
         while let Some(c) = str_it.next() { match c{
             e @ '0'...'9' | e @ 'A'...'F' | e @ 'a'...'f' => {
-                match inprefix.radix_in {
-                    Base::Ten => {
-                        match e {
-                            '0'...'9' => {},
-                            _ => {
-                                warn_incomplete_conv(str_in);
-                                break;
-                            }
+                if !hex_input {
+                    match e {
+                        '0'...'9' => {},
+                        _ => {
+                            warn_incomplete_conv(str_in);
+                            break;
                         }
                     }
-                    _ => {}
+                }
+                if ret.decimal_pos.is_some() && pos_before_first_nonzero_after_decimal.is_none() && e != '0' {
+                    pos_before_first_nonzero_after_decimal = Some(i-1);
                 }
                 if let Some(max_sd) = max_sd_opt {
                     if i == max_sd {
@@ -55,12 +86,18 @@ impl FloatAnalysis {
                         break;
                     }
                 }
-                if let Some(p) = ret.decimal_pos {
-                    if let Some(max_after_dec) = max_after_dec_opt {
-                        if (i-1) - p == max_after_dec {
-                            break
+                if let Some(max_after_dec) = max_after_dec_opt {
+                    if let Some(p) = ret.decimal_pos {
+                        if has_enough_digits(hex_input, hex_output, i, p, max_after_dec) {
+                            break;
                         }
                     }
+                } else if let Some(max_sd) = max_sd_opt {
+                    if let Some(p) = pos_before_first_nonzero_after_decimal {
+                        if has_enough_digits(hex_input, hex_output, i, p, max_sd) {
+                            break;
+                        }                        
+                    }
                 }
             },
             '.' => {
@@ -72,7 +109,6 @@ impl FloatAnalysis {
                 }
             }
             _ => {
-                println!("awarn2");
                 warn_incomplete_conv(str_in);
                 break;
             }

src/printf/tokenize/num_format/formatters/floatf.rs

@@ -25,8 +25,8 @@ impl Formatter for Floatf {
             &str_in,
             inprefix,
             None,
-            Some(second_field as usize)
-                );
+            Some(second_field as usize),
+            false);
         let f = get_primitive_dec(
             inprefix,
             &str_in[inprefix.offset..],

src/printf/tokenize/num_format/formatters/mod.rs

@@ -1,5 +1,6 @@
 pub mod intf;
 pub mod floatf;
+pub mod cninetyninehexfloatf;
 pub mod scif;
 pub mod decf;
 mod float_common;

src/printf/tokenize/num_format/formatters/scif.rs

@@ -25,8 +25,8 @@ impl Formatter for Scif {
             str_in,
             inprefix,
             Some(second_field as usize+1),
-            None
-                );
+            None,
+            false);
         let f = get_primitive_dec(
             inprefix,
             &str_in[inprefix.offset..],

src/printf/tokenize/num_format/num_format.rs

@@ -7,6 +7,7 @@ use super::format_field::{FormatField, FieldType};
 use super::formatter::{Formatter, FormatPrimitive, InPrefix, Base};
 use super::formatters::intf::Intf;
 use super::formatters::floatf::Floatf;
+use super::formatters::cninetyninehexfloatf::CninetyNineHexFloatf;
 use super::formatters::scif::Scif;
 use super::formatters::decf::Decf;
 
@@ -200,6 +201,7 @@ pub fn num_format(
     let fmtr : Box<Formatter> = match *field.field_type {
         FieldType::Intf => Box::new(Intf::new()),
         FieldType::Floatf => Box::new(Floatf::new()),
+        FieldType::CninetyNineHexFloatf => Box::new(CninetyNineHexFloatf::new()),
         FieldType::Scif => Box::new(Scif::new()),
         FieldType::Decf => Box::new(Decf::new()),
         _ => { panic!("asked to do num format with non-num fieldtype"); }

src/printf/tokenize/sub.rs

@@ -67,6 +67,7 @@ impl Sub {
             's' | 'b' => FieldType::Strf,
             'd' | 'i' | 'u' | 'o' | 'x' | 'X' => FieldType::Intf,
             'f' | 'F' => FieldType::Floatf,
+            'a' | 'A' => FieldType::CninetyNineHexFloatf,
             'e' | 'E' => FieldType::Scif,
             'g' | 'G' => FieldType::Decf,
             'c' => FieldType::Charf,
@@ -157,9 +158,10 @@ impl SubParser {
         // though, as we want to mimic the original behavior of printing
         // the field as interpreted up until the error in the field.
 
-        let mut legal_fields=vec!['b', 'c', 'd', 'e', 'E',
-                                  'f', 'g', 'G', 'i', 'o',
-                                  's', 'u', 'x', 'X'];
+        let mut legal_fields=vec![
+            //'a', 'A', //c99 hex float implementation not yet complete
+                                  'b', 'c', 'd', 'e', 'E', 'f',
+                                  'F', 'g', 'G', 'i', 'o','s', 'u', 'x', 'X'];
         let mut specifiers=vec!['h', 'j', 'l', 'L', 't', 'z'];
         legal_fields.sort();
         specifiers.sort();