btrfs-progs: add helper for copying paths

Check the source path length and do the copy.

Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/utils.c b/utils.c
index 591b2a1..b458e6b 100644 (file)
--- a/utils.c
+++ b/utils.c
@@ -2871,3 +2871,22 @@ int btrfs_check_nodesize(u32 nodesize, u32 sectorsize)
        }
        return 0;
 }
+
+/*
+ * Copy a path argument from SRC to DEST and check the SRC length if it's at
+ * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
+ * the buffer.
+ * The destination buffer is zero terminated.
+ * Return < 0 for error, 0 otherwise.
+ */
+int arg_copy_path(char *dest, const char *src, int destlen)
+{
+       size_t len = strlen(src);
+
+       if (len >= PATH_MAX || len >= destlen)
+               return -ENAMETOOLONG;
+
+       __strncpy__null(dest, src, destlen);
+
+       return 0;
+}

diff --git a/utils.h b/utils.h
index 7260035..8ed18e1 100644 (file)
--- a/utils.h
+++ b/utils.h
@@ -135,6 +135,7 @@ int get_mountpt(char *dev, char *mntpt, size_t size);
 u64 parse_size(char *s);
 u64 parse_qgroupid(const char *p);
 u64 arg_strtou64(const char *str);
+int arg_copy_path(char *dest, const char *src, int destlen);
 int open_file_or_dir(const char *fname, DIR **dirstream);
 int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags);
 void close_file_or_dir(int fd, DIR *dirstream);