Implementation of getrlimit and getdtablesize

include/sys/resource.h

@@ -15,4 +15,32 @@
 int getpriority(int, int);
 int setpriority(int, int, int);
 
+#ifdef _POSIX_SOURCE
+
+#include <sys/time.h>
+
+typedef unsigned long rlim_t;
+
+#define RLIM_INFINITY ((rlim_t) -1)
+#define RLIM_SAVED_CUR RLIM_INFINITY
+#define RLIM_SAVED_MAX RLIM_INFINITY
+
+struct rlimit
+{
+	rlim_t rlim_cur;
+	rlim_t rlim_max;
+};
+
+#define RLIMIT_CORE	1
+#define RLIMIT_CPU	2
+#define RLIMIT_DATA	3
+#define RLIMIT_FSIZE	4
+#define RLIMIT_NOFILE	5
+#define RLIMIT_STACK	6
+#define RLIMIT_AS	7
+
+int getrlimit(int resource, struct rlimit *rlp);
+
+#endif /* defined(_POSIX_SOURCE) */
+
 #endif

include/unistd.h

@@ -216,4 +216,8 @@ _PROTOTYPE( int initgroups, (const char *name, gid_t basegid)		);
 
 #endif
 
+#ifdef _POSIX_SOURCE
+_PROTOTYPE( int getdtablesize, (void)                                   );
+#endif
+
 #endif /* _UNISTD_H */

lib/other/Makefile.in

@@ -77,6 +77,7 @@ libc_FILES=" \
 	random.c \
 	realpath.c \
 	rindex.c \
+	rlimit.c \
 	setenv.c \
 	setgroups.c \
 	settimeofday.c \

lib/other/rlimit.c

@@ -0,0 +1,55 @@
+/*	getdtablesize, getrlimit              Author: Erik van der Kouwe
+ *      query resource consumtion limits      4 December 2009
+ *
+ * Based on these specifications:
+ * http://www.opengroup.org/onlinepubs/007908775/xsh/getdtablesize.html 
+ * http://www.opengroup.org/onlinepubs/007908775/xsh/getrlimit.html 
+ */
+ 
+#include <errno.h>
+#include <limits.h>
+#include <sys/resource.h>
+#include <unistd.h>
+
+int getdtablesize(void)
+{
+	return OPEN_MAX;
+}
+
+int getrlimit(int resource, struct rlimit *rlp)
+{
+	rlim_t limit;
+	
+	switch (resource)
+	{
+		case RLIMIT_CORE:
+			/* no core currently produced */
+			limit = 0;
+			break;
+
+		case RLIMIT_CPU:
+		case RLIMIT_DATA:
+		case RLIMIT_FSIZE:
+		case RLIMIT_STACK:
+		case RLIMIT_AS:
+			/* no limit enforced (however architectural limits 
+			 * may apply) 
+			 */	
+			limit = RLIM_INFINITY;
+			break;
+
+		case RLIMIT_NOFILE:
+			limit = OPEN_MAX;
+			break;
+
+		default:
+			errno = EINVAL;
+			return -1;
+	}		
+
+	/* return limit */
+	rlp->rlim_cur = limit;
+	rlp->rlim_max = limit;
+	return 0;
+}
+

man/man3/getdtablesize.3

@@ -0,0 +1,16 @@
+.TH GETDTABLESIZE 3  "December 4, 2009"
+.UC 4
+.SH NAME
+getdtablesize \- query maximum number of open files
+.SH SYNOPSIS
+.nf
+.ft B
+#include <unistd.h>
+
+int getdtablesize(void);
+.fi
+.SH DESCRIPTION
+getdtablesize returns the number of files that may be open at the same time
+in a process.
+.SH "RETURN VALUE
+The number of files that may be open at the same time in a process is returned.

man/man3/getrlimit.3

@@ -0,0 +1,23 @@
+.TH GETRLIMIT 3  "December 4, 2009"
+.UC 4
+.SH NAME
+getrlimit \- query resource consumption limits
+.SH SYNOPSIS
+.nf
+.ft B
+#include <sys/resource.h>
+
+int getrlimit(int \fIresource\fP, struct rlimit *\fIrlp\fP);
+.fi
+.SH DESCRIPTION
+getrlimit queries the current resource limit regarding the specified
+\fIresource\fP. This can be one of the following: RLIMIT_CORE, RLIMIT_CPU,
+RLIMIT_DATA, RLIMIT_FSIZE, RLIMIT_NOFILE, RLIMIT_STACK or RLIMIT_AS.
+The soft limit is specified in \fIrlp\fP\->rlim_cur and the hard limit in
+\fIrlp\fP\->rlim_max. On MINIX, these are currently always the same.
+A value of RLIM_INFINITY specifies that no limit is enforced, although
+architectural limits may still apply.
+.SH "RETURN VALUE
+If the function succeeds, 0 is returned.
+If the function fails, -1 is returned and errno is set to indicate the
+cause of the failure.