Home | History | Annotate | Download | only in posix 
      1 /* cat.c - copy inputs to stdout.
      2  *
      3  * Copyright 2006 Rob Landley <rob (at) landley.net>
      4  *
      5  * See http://opengroup.org/onlinepubs/9699919799/utilities/cat.html
      6  *
      7  * And "Cat -v considered harmful" at
      8  *   http://cm.bell-labs.com/cm/cs/doc/84/kp.ps.gz
      9 
     10 USE_CAT(NEWTOY(cat, "u"USE_CAT_V("vte"), TOYFLAG_BIN))
     11 USE_CATV(NEWTOY(catv, USE_CATV("vte"), TOYFLAG_USR|TOYFLAG_BIN))
     12 
     13 config CAT
     14   bool "cat"
     15   default y
     16   help
     17     usage: cat [-u] [file...]
     18 
     19     Copy (concatenate) files to stdout.  If no files listed, copy from stdin.
     20     Filename "-" is a synonym for stdin.
     21 
     22     -u	Copy one byte at a time (slow)
     23 
     24 config CAT_V
     25   bool "cat -etv"
     26   default n
     27   depends on CAT
     28   help
     29     usage: cat [-evt]
     30 
     31     -e	Mark each newline with $
     32     -t	Show tabs as ^I
     33     -v	Display nonprinting characters as escape sequences with M-x for
     34     	high ascii characters (>127), and ^x for other nonprinting chars
     35 
     36 config CATV
     37   bool "catv"
     38   default y
     39   help
     40     usage: catv [-evt] [filename...]
     41 
     42     Display nonprinting characters as escape sequences. Use M-x for
     43     high ascii characters (>127), and ^x for other nonprinting chars.
     44 
     45     -e	Mark each newline with $
     46     -t	Show tabs as ^I
     47     -v	Don't use ^x or M-x escapes
     48 */
     49 
     50 #define FOR_cat
     51 #define FORCE_FLAGS
     52 #include "toys.h"
     53 
     54 static void do_cat(int fd, char *name)
     55 {
     56   int i, len, size=(toys.optflags & FLAG_u) ? 1 : sizeof(toybuf);
     57 
     58   for(;;) {
     59     len = read(fd, toybuf, size);
     60     if (len < 0) {
     61       toys.exitval = EXIT_FAILURE;
     62       perror_msg_raw(name);
     63     }
     64     if (len < 1) break;
     65     if ((CFG_CAT_V || CFG_CATV) && (toys.optflags&~FLAG_u)) {
     66       for (i=0; i<len; i++) {
     67         char c=toybuf[i];
     68 
     69         if (c > 126 && (toys.optflags & FLAG_v)) {
     70           if (c > 127) {
     71             printf("M-");
     72             c -= 128;
     73           }
     74           if (c == 127) {
     75             printf("^?");
     76             continue;
     77           }
     78         }
     79         if (c < 32) {
     80           if (c == 10) {
     81             if (toys.optflags & FLAG_e) xputc('$');
     82           } else if (toys.optflags & (c==9 ? FLAG_t : FLAG_v)) {
     83             printf("^%c", c+'@');
     84             continue;
     85           }
     86         }
     87         xputc(c);
     88       }
     89     } else xwrite(1, toybuf, len);
     90   }
     91 }
     92 
     93 void cat_main(void)
     94 {
     95   loopfiles(toys.optargs, do_cat);
     96 }
     97 
     98 void catv_main(void)
     99 {
    100   toys.optflags ^= FLAG_v;
    101   loopfiles(toys.optargs, do_cat);
    102 }
    103