From bde7ac5023ff634fb8bb282e16deab3fd477dcdf Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Thu, 3 May 2012 15:05:53 +0200 Subject: truncates the output to the width of stderr --- Truncater.java | 150 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 Truncater.java diff --git a/Truncater.java b/Truncater.java new file mode 100644 index 0000000..a5eb99d --- /dev/null +++ b/Truncater.java @@ -0,0 +1,150 @@ +import java.io.*; + +public class Truncater +{ + public static void main(final String... args) throws IOException + { + final int width; + if ((width = getWidth()) > 15) //sanity + { + final OutputStream stdout = new BufferedOutputStream(System.out); + OutputStream out = new OutputStream() + { + /** + * The number of column on the current line + */ + private int x = 0; + + /** + * Escape sequence state + */ + private int esc = 0; + + /** + * Last bytes as written + */ + private boolean ok = true; + + + /** + * {@inheritDoc} + */ + @Override + public void write(final int b) throws IOException + { + if (this.esc == 0) + { + if (b == '\n') + { + if (x >= width) + { + write('\033'); + write('['); + write('4'); + write('9'); + write('m'); + } + this.x = -1; + } + else if (b == '\t') + { + int nx = 8 - (x & 7); + for (int i = 0; i < nx; i++) + write(' '); + return; //(!) + } + else if (b == '\033') + this.esc = 1; + } + else if (this.esc == 1) + { + if (b == '[') this.esc = 2; + else if (b == ']') this.esc = 3; + else this.esc = 10; + } + else if (this.esc == 2) + { + if ((('a' <= b) && (b <= 'z')) || (('A' <= b) && (b <= 'Z'))) + this.esc = 10; + } + else if ((this.esc == 3) && (b == 'P')) + { + this.esc = ~0; + } + else if (this.esc < 0) + { + this.esc--; + if (this.esc == ~7) + this.esc = 10; + } + else + this.esc = 10; + + if ((x < width) || (this.esc != 0) || (ok && ((b & 0xC0) == 0x80))) + { + stdout.write(b); + if (this.esc == 0) + if ((b & 0xC0) != 0x80) + x++; + ok = true; + } + else + ok = false; + if (this.esc == 10) + this.esc = 0; + } + + /** + * {@inheritDoc} + */ + @Override + public void flush() throws IOException + { + stdout.flush(); + } + }; + + System.setOut(new PrintStream(out)); + } + + + InputStream in = System.in; + OutputStream out = System.out; + + for (int d; (d = in.read()) != -1;) + out.write(d); + out.flush(); + } + + /** + * Gets the width of the terminal + * + * @return The width of the terminal + */ + public static int getWidth() + { + try + { + Process process = (new ProcessBuilder("/bin/sh", "-c", "tput cols 2> " + (new File("/dev/stderr")).getCanonicalPath())).start(); + String rcs = new String(); + InputStream stream = process.getInputStream(); + int c; + while (((c = stream.read()) != '\n') && (c != -1)) + rcs += (char)c; + try + { + stream.close(); + } + catch (final Throwable err) + { + //Ignore + } + return Integer.parseInt(rcs); + } + catch (final Throwable err) + { + return -1; + } + } +} + -- cgit