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 #include "libbb.h"
  10
  11 FILE* FAST_FUNC fopen_or_warn(const char *path, const char *mode)
  12 {
  13         FILE *fp = fopen(path, mode);
  14         if (!fp) {
  15                 bb_simple_perror_msg(path);
  16                 //errno = 0; /* why? */
  17         }
  18         return fp;
  19 }
  20
  21 FILE* FAST_FUNC fopen_for_read(const char *path)
  22 {
  23         return fopen(path, "r");
  24 }
  25
  26 FILE* FAST_FUNC xfopen_for_read(const char *path)
  27 {
  28         return xfopen(path, "r");
  29 }
  30
  31 FILE* FAST_FUNC fopen_for_write(const char *path)
  32 {
  33         return fopen(path, "w");
  34 }
  35
  36 FILE* FAST_FUNC xfopen_for_write(const char *path)
  37 {
  38         return xfopen(path, "w");
  39 }
  40
  41 static FILE* xfdopen_helper(unsigned fd_and_rw_bit)
  42 {
  43         FILE* fp = fdopen(fd_and_rw_bit >> 1, fd_and_rw_bit & 1 ? "w" : "r");
  44         if (!fp)
  45                 bb_die_memory_exhausted();
  46         return fp;
  47 }
  48 FILE* FAST_FUNC xfdopen_for_read(int fd)
  49 {
  50         return xfdopen_helper(fd << 1);
  51 }
  52 FILE* FAST_FUNC xfdopen_for_write(int fd)
  53 {
  54         return xfdopen_helper((fd << 1) + 1);
  55 }