libexplain  1.4.D001
libexplain/calloc_or_die.c
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00001 /*
00002  * libexplain - Explain errno values returned by libc functions
00003  * Copyright (C) 2010, 2012, 2013 Peter Miller
00004  *
00005  * This program is free software; you can redistribute it and/or modify it
00006  * under the terms of the GNU Lesser General Public License as published by
00007  * the Free Software Foundation; either version 3 of the License, or (at
00008  * your option) any later version.
00009  *
00010  * This program is distributed in the hope that it will be useful, but
00011  * WITHOUT ANY WARRANTY; without even the implied warranty of
00012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
00013  * General Public License for more details.
00014  *
00015  * You should have received a copy of the GNU Lesser General Public License
00016  * along with this program. If not, see <http://www.gnu.org/licenses/>.
00017  */
00018 
00019 #include <libexplain/ac/errno.h>
00020 #include <libexplain/ac/stdlib.h>
00021 
00022 #include <libexplain/calloc.h>
00023 #include <libexplain/output.h>
00024 
00025 
00026 void *
00027 explain_calloc_or_die(size_t nmemb, size_t size)
00028 {
00029     void            *result;
00030 
00031     result = explain_calloc_on_error(nmemb, size);
00032     if (!result)
00033     {
00034         explain_output_exit_failure();
00035     }
00036     return result;
00037 }
00038 
00039 
00040 void *
00041 explain_calloc_on_error(size_t nmemb, size_t size)
00042 {
00043     void            *result;
00044     int             hold_errno;
00045 
00046     hold_errno = errno;
00047     errno = 0;
00048     result = calloc(nmemb, size);
00049     if (!result)
00050     {
00051         /* this is deliberately conservative */
00052         size_t nmemb_avail = (((size_t)-1) / 3 * 2 / size);
00053         hold_errno = (errno ? errno : (nmemb_avail < nmemb ? EINVAL : ENOMEM));
00054         explain_output_error
00055         (
00056             "%s",
00057             explain_errno_calloc(hold_errno, nmemb, size)
00058         );
00059     }
00060     errno = hold_errno;
00061     return result;
00062 }
00063 
00064 
00065 /* vim: set ts=8 sw=4 et : */