tools lib api fs: Add {tracefs,debugfs}_configured() functions

Add tracefs_configured() to return true if tracefs is configured in the
kernel (succeeds to find tracefs), and debugfs_configured() if debugfs
is configured in the kernel (succeeds to find debugfs).

Signed-off-by: Steven Rostedt <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/lib/api/fs/debugfs.c

···
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <stdbool.h>
 #include <sys/vfs.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <sys/mount.h>
 #include <linux/kernel.h>
 
···
 };
 
 static bool debugfs_found;
+
+bool debugfs_configured(void)
+{
+	return debugfs_find_mountpoint() != NULL;
+}
 
 /* find the path to the mounted debugfs */
 const char *debugfs_find_mountpoint(void)

tools/lib/api/fs/debugfs.h

···
 #define PERF_DEBUGFS_ENVIRONMENT "PERF_DEBUGFS_DIR"
 #endif
 
+bool debugfs_configured(void);
 const char *debugfs_find_mountpoint(void);
 char *debugfs_mount(const char *mountpoint);
 

tools/lib/api/fs/findfs.h

···
 #ifndef __API_FINDFS_H__
 #define __API_FINDFS_H__
 
+#include <stdbool.h>
+
 #define _STR(x) #x
 #define STR(x) _STR(x)
 

tools/lib/api/fs/tracefs.c

···
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <stdbool.h>
 #include <sys/vfs.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <sys/mount.h>
 #include <linux/kernel.h>
 
···
 };
 
 static bool tracefs_found;
+
+bool tracefs_configured(void)
+{
+	return tracefs_find_mountpoint() != NULL;
+}
 
 /* find the path to the mounted tracefs */
 const char *tracefs_find_mountpoint(void)

tools/lib/api/fs/tracefs.h

···
 #define PERF_TRACEFS_ENVIRONMENT "PERF_TRACEFS_DIR"
 #endif
 
+bool tracefs_configured(void);
 const char *tracefs_find_mountpoint(void);
 int tracefs_valid_mountpoint(const char *debugfs);
 char *tracefs_mount(const char *mountpoint);