1 files changed, 117 insertions, 0 deletions
diff --git a/newlib/libc/sys/linux/machine/i386/get_clockfreq.c b/newlib/libc/sys/linux/machine/i386/get_clockfreq.c
new file mode 100644
index 000000000..ea46ed427
--- /dev/null
+++ b/newlib/libc/sys/linux/machine/i386/get_clockfreq.c
@@ -0,0 +1,117 @@
+/* Get frequency of the system processor.  i386/Linux version.
+   Copyright (C) 2000, 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <libc-internal.h>
+
+static
+void *memmem (const void *a, size_t len1, const void *b, size_t len2)
+{
+  char *end, *start;
+  char *ptr1, *ptr2;
+
+  if (len2 > len1)
+    return NULL;
+
+  start = (char *)a;
+  end = start + len1;
+
+  while (start < end)
+    {
+      size_t len = len2;
+      ptr1 = start;
+      ptr2 = (char *)b;
+      while (len > 0 && *ptr1++ == *ptr2++)
+        --len;
+      if (len == 0)
+        return start;
+      ++start;
+    }
+
+  return NULL;
+} 
+
+hp_timing_t
+__get_clockfreq (void)
+{
+  /* We read the information from the /proc filesystem.  It contains at
+     least one line like
+	cpu MHz         : 497.840237
+     or also
+	cpu MHz         : 497.841
+     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, "cpu 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;
+}