xref: /llvm-project/libc/src/unistd/linux/sysconf.cpp (revision 7477b61b2416ca130bd3ed9bbc96988e5de17623)
11ac525b2SMichael Jones //===-- Linux implementation of sysconf -----------------------------------===//
21ac525b2SMichael Jones //
31ac525b2SMichael Jones // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
41ac525b2SMichael Jones // See https://llvm.org/LICENSE.txt for license information.
51ac525b2SMichael Jones // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
61ac525b2SMichael Jones //
71ac525b2SMichael Jones //===----------------------------------------------------------------------===//
81ac525b2SMichael Jones 
91ac525b2SMichael Jones #include "src/unistd/sysconf.h"
101ac525b2SMichael Jones 
111ac525b2SMichael Jones #include "src/__support/common.h"
121ac525b2SMichael Jones 
13*7477b61bSTristan Ross #include "hdr/unistd_macros.h"
145ff3ff33SPetr Hosek #include "src/__support/macros/config.h"
15803437dbSMichael Jones #include "src/errno/libc_errno.h"
160cf20c29SSchrodinger ZHU Yifan #include "src/sys/auxv/getauxval.h"
170cf20c29SSchrodinger ZHU Yifan #include <sys/auxv.h>
181ac525b2SMichael Jones 
195ff3ff33SPetr Hosek namespace LIBC_NAMESPACE_DECL {
201ac525b2SMichael Jones 
211ac525b2SMichael Jones LLVM_LIBC_FUNCTION(long, sysconf, (int name)) {
221ac525b2SMichael Jones   long ret = 0;
230cf20c29SSchrodinger ZHU Yifan   if (name == _SC_PAGESIZE)
240cf20c29SSchrodinger ZHU Yifan     return static_cast<long>(getauxval(AT_PAGESZ));
250cf20c29SSchrodinger ZHU Yifan 
261ac525b2SMichael Jones   // TODO: Complete the rest of the sysconf options.
271ac525b2SMichael Jones   if (ret < 0) {
28204587a3SSiva Chandra Reddy     libc_errno = EINVAL;
291ac525b2SMichael Jones     return -1;
301ac525b2SMichael Jones   }
311ac525b2SMichael Jones   return ret;
321ac525b2SMichael Jones }
331ac525b2SMichael Jones 
345ff3ff33SPetr Hosek } // namespace LIBC_NAMESPACE_DECL
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