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Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/ia64/get_clockfreq.c')
-rw-r--r--ports/sysdeps/unix/sysv/linux/ia64/get_clockfreq.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/ia64/get_clockfreq.c b/ports/sysdeps/unix/sysv/linux/ia64/get_clockfreq.c
new file mode 100644
index 0000000000..4c1777a516
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/ia64/get_clockfreq.c
@@ -0,0 +1,88 @@
+/* Get frequency of the system processor. IA-64/Linux version.
+ Copyright (C) 2001 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <libc-internal.h>
+
+
+hp_timing_t
+__get_clockfreq (void)
+{
+ /* We read the information from the /proc filesystem. It contains at
+ least one line like
+ itc MHz : 733.390988
+ We search for this line and convert the number in an integer. */
+ static hp_timing_t result;
+ int fd;
+
+ /* If this function was called before, we know the result. */
+ if (result != 0)
+ return result;
+
+ fd = open ("/proc/cpuinfo", O_RDONLY);
+ if (__builtin_expect (fd != -1, 1))
+ {
+ /* XXX AFAIK the /proc filesystem can generate "files" only up
+ to a size of 4096 bytes. */
+ char buf[4096];
+ ssize_t n;
+
+ n = read (fd, buf, sizeof buf);
+ if (__builtin_expect (n, 1) > 0)
+ {
+ char *mhz = memmem (buf, n, "itc MHz", 7);
+
+ if (__builtin_expect (mhz != NULL, 1))
+ {
+ char *endp = buf + n;
+ int seen_decpoint = 0;
+ int ndigits = 0;
+
+ /* Search for the beginning of the string. */
+ while (mhz < endp && (*mhz < '0' || *mhz > '9') && *mhz != '\n')
+ ++mhz;
+
+ while (mhz < endp && *mhz != '\n')
+ {
+ if (*mhz >= '0' && *mhz <= '9')
+ {
+ result *= 10;
+ result += *mhz - '0';
+ if (seen_decpoint)
+ ++ndigits;
+ }
+ else if (*mhz == '.')
+ seen_decpoint = 1;
+
+ ++mhz;
+ }
+
+ /* Compensate for missing digits at the end. */
+ while (ndigits++ < 6)
+ result *= 10;
+ }
+ }
+
+ close (fd);
+ }
+
+ return result;
+}