X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fgetdtablesize.c;h=9947405af61b9773e5fc06d96d25ca66990ab76e;hb=a77413333408e54b8d6c4e19918098794cef4b4b;hp=5be1e8337310058744f7cb5f09b79df77dca5ba2;hpb=a7b40bdb82e8d3448d8007b061077ecfb3b6bfdc;p=gnulib.git diff --git a/lib/getdtablesize.c b/lib/getdtablesize.c index 5be1e8337..9947405af 100644 --- a/lib/getdtablesize.c +++ b/lib/getdtablesize.c @@ -1,5 +1,5 @@ /* getdtablesize() function for platforms that don't have it. - Copyright (C) 2008-2009 Free Software Foundation, Inc. + Copyright (C) 2008-2013 Free Software Foundation, Inc. Written by Bruno Haible , 2008. This program is free software: you can redistribute it and/or modify @@ -24,6 +24,29 @@ #include +#include "msvc-inval.h" + +#if HAVE_MSVC_INVALID_PARAMETER_HANDLER +static int +_setmaxstdio_nothrow (int newmax) +{ + int result; + + TRY_MSVC_INVAL + { + result = _setmaxstdio (newmax); + } + CATCH_MSVC_INVAL + { + result = -1; + } + DONE_MSVC_INVAL; + + return result; +} +# define _setmaxstdio _setmaxstdio_nothrow +#endif + /* Cache for the previous getdtablesize () result. */ static int dtablesize; @@ -33,27 +56,27 @@ getdtablesize (void) if (dtablesize == 0) { /* We are looking for the number N such that the valid file descriptors - are 0..N-1. It can be obtained through a loop as follows: - { - int fd; - for (fd = 3; fd < 65536; fd++) - if (dup2 (0, fd) == -1) - break; - return fd; - } - On Windows XP, the result is 2048. - The drawback of this loop is that it allocates memory for a libc - internal array that is never freed. - - The number N can also be obtained as the upper bound for - _getmaxstdio (). _getmaxstdio () returns the maximum number of open - FILE objects. The sanity check in _setmaxstdio reveals the maximum - number of file descriptors. This too allocates memory, but it is - freed when we call _setmaxstdio with the original value. */ + are 0..N-1. It can be obtained through a loop as follows: + { + int fd; + for (fd = 3; fd < 65536; fd++) + if (dup2 (0, fd) == -1) + break; + return fd; + } + On Windows XP, the result is 2048. + The drawback of this loop is that it allocates memory for a libc + internal array that is never freed. + + The number N can also be obtained as the upper bound for + _getmaxstdio (). _getmaxstdio () returns the maximum number of open + FILE objects. The sanity check in _setmaxstdio reveals the maximum + number of file descriptors. This too allocates memory, but it is + freed when we call _setmaxstdio with the original value. */ int orig_max_stdio = _getmaxstdio (); unsigned int bound; for (bound = 0x10000; _setmaxstdio (bound) < 0; bound = bound / 2) - ; + ; _setmaxstdio (orig_max_stdio); dtablesize = bound; }