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-rw-r--r--debug/pcprofile.c75
1 files changed, 75 insertions, 0 deletions
diff --git a/debug/pcprofile.c b/debug/pcprofile.c
new file mode 100644
index 0000000000..b5dc4e709c
--- /dev/null
+++ b/debug/pcprofile.c
@@ -0,0 +1,75 @@
+/* Profile PC and write result to FIFO.
+   Copyright (C) 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+/* Nonzero if we are actually doing something.  */
+static int active;
+
+/* The file descriptor of the FIFO.  */
+static int fd;
+
+
+static void
+__attribute__ ((constructor))
+install (void)
+{
+  /* See whether the environment variable `PCPROFILE_OUTPUT' is defined.
+     If yes, it should name a FIFO.  We open it and mark ourself as active.  */
+  const char *outfile = getenv ("PCPROFILE_OUTPUT");
+
+  if (outfile != NULL && *outfile != '\0')
+    {
+      fd = open (outfile, O_RDWR);
+
+      if (fd != -1)
+	active = 1;
+    }
+}
+
+
+static void
+__attribute__ ((destructor))
+uninstall (void)
+{
+  if (active)
+    close (fd);
+}
+
+
+void
+__cyg_profile_func_enter (void *this_fn, void *call_site)
+{
+  void *buf[2];
+
+  if (! active)
+    return;
+
+  /* Now write out the current position and that of the caller.  We do
+     this now, and don't cache the because we want real-time output.  */
+  buf[0] = this_fn;
+  buf[1] = call_site;
+
+  write (fd, buf, sizeof buf);
+}
+/* We don't handle entry and exit differently here.  */
+strong_alias (__cyg_profile_func_enter, __cyg_profile_func_exit)