tools lib fs: Adopt filename__read_int from tools/perf/

Will be useful for new helpers to read sysctl values.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/api/fs/fs.c

@@ -7,6 +7,10 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/vfs.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
 
 #include "debugfs.h"
 #include "fs.h"
@@ -163,3 +167,20 @@ const char *name##__mountpoint(void)	\
 
 FS__MOUNTPOINT(sysfs,  FS__SYSFS);
 FS__MOUNTPOINT(procfs, FS__PROCFS);
+
+int filename__read_int(const char *filename, int *value)
+{
+	char line[64];
+	int fd = open(filename, O_RDONLY), err = -1;
+
+	if (fd < 0)
+		return -1;
+
+	if (read(fd, line, sizeof(line)) > 0) {
+		*value = atoi(line);
+		err = 0;
+	}
+
+	close(fd);
+	return err;
+}

tools/lib/api/fs/fs.h

@@ -11,4 +11,6 @@
 
 const char *sysfs__mountpoint(void);
 const char *procfs__mountpoint(void);
+
+int filename__read_int(const char *filename, int *value);
 #endif /* __API_FS__ */

tools/perf/util/util.c

@@ -442,23 +442,6 @@ unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
 	return (unsigned long) -1;
 }
 
-int filename__read_int(const char *filename, int *value)
-{
-	char line[64];
-	int fd = open(filename, O_RDONLY), err = -1;
-
-	if (fd < 0)
-		return -1;
-
-	if (read(fd, line, sizeof(line)) > 0) {
-		*value = atoi(line);
-		err = 0;
-	}
-
-	close(fd);
-	return err;
-}
-
 int filename__read_str(const char *filename, char **buf, size_t *sizep)
 {
 	size_t size = 0, alloc_size = 0;

tools/perf/util/util.h

@@ -343,7 +343,6 @@ char *get_srcline(struct dso *dso, unsigned long addr, struct symbol *sym,
 		  bool show_sym);
 void free_srcline(char *srcline);
 
-int filename__read_int(const char *filename, int *value);
 int filename__read_str(const char *filename, char **buf, size_t *sizep);
 int perf_event_paranoid(void);