Implement lttng_iterate_fd wrapper

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/wrapper/fdtable.c b/wrapper/fdtable.c
new file mode 100644 (file)
index 0000000..a44beb5
--- /dev/null
+++ b/wrapper/fdtable.c
@@ -0,0 +1,57 @@
+/*
+ * wrapper/fdtable.c
+ *
+ * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This 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; only
+ * version 2.1 of the License.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/version.h>
+#include <linux/spinlock.h>
+#include "fdtable.h"
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,7,0))
+
+/*
+ * Reimplementation of iterate_fd() for kernels between 2.6.32 and 3.6
+ * (inclusive).
+ */
+int lttng_iterate_fd(struct files_struct *files,
+               unsigned int first,
+               int (*cb)(const void *, struct file *, unsigned int),
+               const void *ctx)
+{
+       struct fdtable *fdt;
+       struct file *filp;
+       unsigned int i;
+       int res = 0;
+
+       if (!files)
+               return 0;
+       spin_lock(&files->file_lock);
+       fdt = files_fdtable(files);
+       for (i = 0; i < fdt->max_fds; i++) {
+               filp = fcheck_files(files, i);
+               if (!filp)
+                       continue;
+               res = cb(ctx, filp, i);
+               if (res)
+                       break;
+       }
+       spin_unlock(&files->file_lock);
+       return res;
+}
+
+#endif

diff --git a/wrapper/fdtable.h b/wrapper/fdtable.h
new file mode 100644 (file)
index 0000000..7e74290
--- /dev/null
+++ b/wrapper/fdtable.h
@@ -0,0 +1,44 @@
+#ifndef _LTTNG_WRAPPER_FDTABLE_H
+#define _LTTNG_WRAPPER_FDTABLE_H
+
+/*
+ * wrapper/fdtable.h
+ *
+ * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This 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; only
+ * version 2.1 of the License.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/version.h>
+#include <linux/fdtable.h>
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,7,0))
+
+int lttng_iterate_fd(struct files_struct *files,
+               unsigned int first,
+               int (*cb)(const void *, struct file *, unsigned int),
+               const void *ctx);
+
+#else
+
+/*
+ * iterate_fd() appeared at commit
+ * c3c073f808b22dfae15ef8412b6f7b998644139a in the Linux kernel (first
+ * released kernel: v3.7).
+ */
+#define lttng_iterate_fd       iterate_fd
+
+#endif
+#endif /* _LTTNG_WRAPPER_FDTABLE_H */