release/src/router/busybox/libbb/wfopen_input.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * wfopen_input implementation for busybox
   4  *
   5  * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 /* A number of applets need to open a file for reading, where the filename
  11  * is a command line arg.  Since often that arg is '-' (meaning stdin),
  12  * we avoid testing everywhere by consolidating things in this routine.
  13  */
  14
  15 #include "libbb.h"
  16
  17 FILE* FAST_FUNC fopen_or_warn_stdin(const char *filename)
  18 {
  19         FILE *fp = stdin;
  20
  21         if (filename != bb_msg_standard_input
  22          && NOT_LONE_DASH(filename)
  23         ) {
  24                 fp = fopen_or_warn(filename, "r");
  25         }
  26         return fp;
  27 }
  28
  29 FILE* FAST_FUNC xfopen_stdin(const char *filename)
  30 {
  31         FILE *fp = fopen_or_warn_stdin(filename);
  32         if (fp)
  33                 return fp;
  34         xfunc_die();  /* We already output an error message. */
  35 }
  36
  37 int FAST_FUNC open_or_warn_stdin(const char *filename)
  38 {
  39         int fd = STDIN_FILENO;
  40
  41         if (filename != bb_msg_standard_input
  42          && NOT_LONE_DASH(filename)
  43         ) {
  44                 fd = open_or_warn(filename, O_RDONLY);
  45         }
  46
  47         return fd;
  48 }
  49
  50 int FAST_FUNC xopen_stdin(const char *filename)
  51 {
  52         int fd = open_or_warn_stdin(filename);
  53         if (fd >= 0)
  54                 return fd;
  55         xfunc_die();  /* We already output an error message. */
  56 }