od: implement -w (width)

Cargo.lock

@@ -667,6 +667,7 @@ dependencies = [
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "unindent 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "uucore 0.0.1",
 ]
 
 [[package]]

src/od/Cargo.toml

@@ -12,6 +12,7 @@ getopts = "*"
 libc = "*"
 unindent = "*"
 byteorder = "*"
+uucore = { path="../uucore" }
 
 [[bin]]
 name = "od"

src/od/od.rs

@@ -13,12 +13,16 @@ extern crate getopts;
 extern crate unindent;
 extern crate byteorder;
 
+#[macro_use]
+extern crate uucore;
+
 mod multifilereader;
 mod prn_int;
 mod prn_char;
 mod prn_float;
 
-use std::f64;
+use std::cmp;
+use std::io::Write;
 use unindent::*;
 use byteorder::*;
 use multifilereader::*;
@@ -73,7 +77,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
 
     opts.optopt("t", "format", "select output format or formats", "TYPE");
     opts.optflag("v", "output-duplicates", "do not use * to mark line suppression");
-    opts.optopt("w", "width",
+    opts.optflagopt("w", "width",
                 ("output BYTES bytes per output line. 32 is implied when BYTES is not \
                  specified."),
                 "BYTES");
@@ -209,23 +213,36 @@ pub fn uumain(args: Vec<String>) -> i32 {
             formats.push(mkfmt(2, &oct)); // 2 byte octal is the default
         }
 
-        odfunc(&input_offset_base, &inputs, &formats[..])
+        let mut line_bytes = match matches.opt_default("w", "32") {
+            None => 16,
+            Some(s) => {
+                match s.parse::<usize>() {
+                    Ok(i) => { i }
+                    Err(_) => { 2 }
+                }
+            }
+        };
+        let min_bytes = formats.iter().fold(2, |max, next| cmp::max(max, next.itembytes));
+        if line_bytes % min_bytes != 0 {
+            show_warning!("invalid width {}; using {} instead", line_bytes, min_bytes);
+            line_bytes = min_bytes;
         }
 
-const LINEBYTES:usize = 16;
+        odfunc(line_bytes, &input_offset_base, &inputs, &formats[..])
+}
 
-fn odfunc(input_offset_base: &Radix, fnames: &[InputSource], formats: &[OdFormat]) -> i32 {
+fn odfunc(line_bytes: usize, input_offset_base: &Radix, fnames: &[InputSource], formats: &[OdFormat]) -> i32 {
 
     let mut mf = MultifileReader::new(fnames);
     let mut addr = 0;
-    let bytes = &mut [b'\x00'; LINEBYTES];
+    let mut bytes: Vec<u8> = vec![b'\x00'; line_bytes];
     loop {
         // print each line data (or multi-format raster of several lines describing the same data).
 
         print_with_radix(input_offset_base, addr); // print offset
 		// if printing in multiple formats offset is printed only once
 
-        match mf.f_read(bytes) {
+        match mf.f_read(bytes.as_mut_slice()) {
             Ok(0) => {
                 print!("\n");
                 break;

tests/test_od.rs

@@ -223,3 +223,54 @@ fn mit_die_umlauten_getesten() {
     "0000000    U   n   i   v   e   r   s   i   t   ä  **   t       T   ü  **\n0000020    b   i   n   g   e   n\n0000026")
 }
 */
+
+#[test]
+fn test_width(){
+
+    let input : [u8; 8] = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00];
+    let expected_output = unindent("
+            0000000    000000  000000
+            0000004    000000  000000
+            0000010
+            ");
+
+    let result = new_ucmd!().arg("-w4").run_piped_stdin(&input[..]);
+
+    assert_empty_stderr!(result);
+    assert!(result.success);
+    assert_eq!(result.stdout, expected_output);
+}
+
+#[test]
+fn test_invalid_width(){
+
+    let input : [u8; 4] = [0x00, 0x00, 0x00, 0x00];
+    let expected_output = unindent("
+            0000000    000000
+            0000002    000000
+            0000004
+            ");
+
+    let result = new_ucmd!().arg("-w5").run_piped_stdin(&input[..]);
+
+    assert_eq!(result.stderr, "od: warning: invalid width 5; using 2 instead\n");
+    assert!(result.success);
+    assert_eq!(result.stdout, expected_output);
+}
+
+#[test]
+fn test_width_without_value(){
+
+    let input : [u8; 40] = [0 ; 40];
+    let expected_output = unindent("
+            0000000    000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000  000000
+            0000040    000000  000000  000000  000000
+            0000050
+            ");
+
+    let result = new_ucmd!().arg("-w").run_piped_stdin(&input[..]);
+
+    assert_empty_stderr!(result);
+    assert!(result.success);
+    assert_eq!(result.stdout, expected_output);
+}