libbb/wfopen.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  *
   5  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 #include "libbb.h"
  11
  12 FILE* FAST_FUNC fopen_or_warn(const char *path, const char *mode)
  13 {
  14         FILE *fp = fopen(path, mode);
  15         if (!fp) {
  16                 bb_simple_perror_msg(path);
  17                 //errno = 0; /* why? */
  18         }
  19         return fp;
  20 }
  21
  22 FILE* FAST_FUNC fopen_for_read(const char *path)
  23 {
  24         return fopen(path, "r");
  25 }
  26
  27 FILE* FAST_FUNC xfopen_for_read(const char *path)
  28 {
  29         return xfopen(path, "r");
  30 }
  31
  32 FILE* FAST_FUNC fopen_for_write(const char *path)
  33 {
  34         return fopen(path, "w");
  35 }
  36
  37 FILE* FAST_FUNC xfopen_for_write(const char *path)
  38 {
  39         return xfopen(path, "w");
  40 }
  41
  42 static FILE* xfdopen_helper(unsigned fd_and_rw_bit)
  43 {
  44         FILE* fp = fdopen(fd_and_rw_bit >> 1, fd_and_rw_bit & 1 ? "w" : "r");
  45         if (!fp)
  46                 bb_error_msg_and_die(bb_msg_memory_exhausted);
  47         return fp;
  48 }
  49 FILE* FAST_FUNC xfdopen_for_read(int fd)
  50 {
  51         return xfdopen_helper(fd << 1);
  52 }
  53 FILE* FAST_FUNC xfdopen_for_write(int fd)
  54 {
  55         return xfdopen_helper((fd << 1) + 1);
  56 }