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-rw-r--r--lib/libc/gen/sysconf.c188
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diff --git a/lib/libc/gen/sysconf.c b/lib/libc/gen/sysconf.c
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+/*-
+ * Copyright (c) 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Sean Eric Fagan of Cygnus Support.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/sysctl.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+/*
+ * sysconf --
+ * get configurable system variables.
+ *
+ * XXX
+ * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values
+ * not change during the lifetime of the calling process. This would seem
+ * to require that any change to system limits kill all running processes.
+ * A workaround might be to cache the values when they are first retrieved
+ * and then simply return the cached value on subsequent calls. This is
+ * less useful than returning up-to-date values, however.
+ */
+long
+sysconf(name)
+ int name;
+{
+ struct clockinfo clk;
+ struct rlimit rl;
+ size_t len;
+ int mib[2], value;
+
+ len = sizeof(value);
+
+ switch (name) {
+/* 1003.1 */
+ case _SC_ARG_MAX:
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_ARGMAX;
+ break;
+ case _SC_CHILD_MAX:
+ return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur);
+ case _SC_CLK_TCK:
+ return (CLK_TCK);
+ case _SC_JOB_CONTROL:
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_JOB_CONTROL;
+ goto yesno;
+ case _SC_NGROUPS_MAX:
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_NGROUPS;
+ break;
+ case _SC_OPEN_MAX:
+ return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur);
+ case _SC_STREAM_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_STREAM_MAX;
+ break;
+ case _SC_TZNAME_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_TZNAME_MAX;
+ break;
+ case _SC_SAVED_IDS:
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_SAVED_IDS;
+ goto yesno;
+ case _SC_VERSION:
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_POSIX1;
+ break;
+
+/* 1003.2 */
+ case _SC_BC_BASE_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_BC_BASE_MAX;
+ break;
+ case _SC_BC_DIM_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_BC_DIM_MAX;
+ break;
+ case _SC_BC_SCALE_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_BC_SCALE_MAX;
+ break;
+ case _SC_BC_STRING_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_BC_STRING_MAX;
+ break;
+ case _SC_COLL_WEIGHTS_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_COLL_WEIGHTS_MAX;
+ break;
+ case _SC_EXPR_NEST_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_EXPR_NEST_MAX;
+ break;
+ case _SC_LINE_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_LINE_MAX;
+ break;
+ case _SC_RE_DUP_MAX:
+ mib[0] = CTL_USER;
+ mib[1] = USER_RE_DUP_MAX;
+ break;
+ case _SC_2_VERSION:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_VERSION;
+ break;
+ case _SC_2_C_BIND:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_C_BIND;
+ goto yesno;
+ case _SC_2_C_DEV:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_C_DEV;
+ goto yesno;
+ case _SC_2_CHAR_TERM:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_CHAR_TERM;
+ goto yesno;
+ case _SC_2_FORT_DEV:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_FORT_DEV;
+ goto yesno;
+ case _SC_2_FORT_RUN:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_FORT_RUN;
+ goto yesno;
+ case _SC_2_LOCALEDEF:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_LOCALEDEF;
+ goto yesno;
+ case _SC_2_SW_DEV:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_SW_DEV;
+ goto yesno;
+ case _SC_2_UPE:
+ mib[0] = CTL_USER;
+ mib[1] = USER_POSIX2_UPE;
+yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
+ return (-1);
+ if (value == 0)
+ return (-1);
+ return (value);
+ break;
+ default:
+ errno = EINVAL;
+ return (-1);
+ }
+ return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value);
+}
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