LXR busybox/libbb/printable.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Utility routines.
   4 *
   5 * Copyright (C) 2007 Denys Vlasenko
   6 *
   7 * Licensed under GPLv2, see file LICENSE in this source tree.
   8 */
   9
  10#include "libbb.h"
  11
  12void FAST_FUNC fputc_printable(int ch, FILE *file)
  13{
  14        if ((ch & (0x80 + PRINTABLE_META)) == (0x80 + PRINTABLE_META)) {
  15                fputs("M-", file);
  16                ch &= 0x7f;
  17        }
  18        ch = (unsigned char) ch;
  19        if (ch == 0x9b) {
  20                /* VT100's CSI, aka Meta-ESC, is not printable on vt-100 */
  21                ch = '{';
  22                goto print_caret;
  23        }
  24        if (ch < ' ') {
  25                ch += '@';
  26                goto print_caret;
  27        }
  28        if (ch == 0x7f) {
  29                ch = '?';
  30 print_caret:
  31                fputc('^', file);
  32        }
  33        fputc(ch, file);
  34}
  35
  36void FAST_FUNC visible(unsigned ch, char *buf, int flags)
  37{
  38        if (ch == '\t' && !(flags & VISIBLE_SHOW_TABS)) {
  39                goto raw;
  40        }
  41        if (ch == '\n') {
  42                if (flags & VISIBLE_ENDLINE)
  43                        *buf++ = '$';
  44        } else {
  45                if (ch >= 128) {
  46                        ch -= 128;
  47                        *buf++ = 'M';
  48                        *buf++ = '-';
  49                }
  50                if (ch < 32 || ch == 127) {
  51                        *buf++ = '^';
  52                        ch ^= 0x40;
  53                }
  54        }
  55 raw:
  56        *buf++ = ch;
  57        *buf = '\0';
  58}
  59