print.c

UNIX下SH的实现源码

/*
 * print -- loadable ksh-93 style print builtin
 */

#include "bashtypes.h"

#include <errno.h>
#include <limits.h>
#include <stdio.h>

#include "bashansi.h"
#include "shell.h"
#include "builtins.h"
#include "stdc.h"
#include "bashgetopt.h"

#if !defined (errno)
extern int errno;
#endif

int print_builtin ();
static int printargs ();

static FILE *ofp;

extern char *this_command_name;

static char *print_doc[] = {
  "Output the arguments.  The -f option means to use the argument as a",
  "format string as would be supplied to printf(1).  The rest of the",
  "options are as in ksh.",
  (char *)NULL
};

struct builtin print_struct = {
	"print",
	print_builtin,
	BUILTIN_ENABLED,
	print_doc,
	"print [-Rnprs] [-u unit] [-f format] [arguments]",
	(char *)0
};

#ifndef ISOPTION
#define ISOPTION(s, c)	(s[0] == '-' && s[2] == '\0' && s[1] == c)
#endif

int
print_builtin (list)
     WORD_LIST *list;
{
  int c, r, nflag, raw, ofd, sflag;
  char **v, *pfmt, *arg;
  WORD_LIST *l;

  nflag = raw = sflag = 0;
  ofd = 1;
  pfmt = 0;

  reset_internal_getopt ();
  while ((c = internal_getopt (list, "Rnprsu:f:")) != -1)
    {
      switch (c)
	{
	case 'R':
	  raw = 2;
	  loptend = lcurrent;
	  if (loptend && ISOPTION (loptend->word->word, 'n'))
	    {
	      loptend = loptend->next;
	      nflag = 1;
	    }
	  goto opt_end;
	case 'r':
	  raw = 1;
	  break;
	case 'n':
	  nflag = 1;
	  break;
	case 's':
	  sflag = 1;
	  break;
	case 'p':
	  break;	/* NOP */
	case 'u':
	  if (all_digits (list_optarg))
	    ofd = atoi (list_optarg);
	  else
	    {
	      for (l = list; l->next && l->next != lcurrent; l = l->next);
	      lcurrent = loptend = l;
	      goto opt_end;
	    }
	  break;
	case 'f':
	  pfmt = list_optarg;
	  break;
	default:
	  builtin_usage ();
	  return (EX_USAGE);
	}
    }

opt_end:
  list = loptend;

  ofp = (ofd == 1) ? stdout : fdopen (dup (ofd), "w");

  if (pfmt)
    {
      WORD_DESC *w;
      WORD_LIST *nlist;

      w = make_word (pfmt);
      nlist = make_word_list (w, list);
      r = printf_builtin (nlist);
      nlist->next = (WORD_LIST *)NULL;
      dispose_words (nlist);
      return (r);
    }

  if (raw)
    {
      for (l = list; l; l = l->next)
	{
	  fprintf (ofp, "%s", l->word->word);
	  if (l->next)
	    fprintf (ofp, " ");
	}
      if (nflag == 0)
	fprintf (ofp, "\n");
      fflush (ofp);
      return (0);	
    }
        
  r = printargs (list, ofp);
  if (r && nflag == 0)
    fprintf (ofp, "\n");
  if (ofd != 1)
    fclose (ofp);
  return 0;
}

static int
printargs (list, ofp)
     WORD_LIST *list;
     FILE *ofp;
{
  WORD_LIST *l;
  char *ostr;
  int sawc;

  for (sawc = 0, l = list; l; l = l->next)
    {
      ostr = ansicstr (l->word->word, strlen (l->word->word), 0, &sawc, (int *)0);
      fprintf (ofp, "%s", ostr);
      free (ostr);
      if (sawc)
        return (0);
      if (l->next)
        fprintf (ofp, " ");
    }
  return (1);
}