tools: Avoid leaving extra data at the end of copied files

The copyfile() implementation has strange behaviour if the destination
file already exists. Update it to ensure that any existing data in the
destination file is dropped.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/tools/fit_common.c b/tools/fit_common.c
index 4370de2f61cf91e1e08d49ddd5299172631ea592..5ea43f5fec87256e5af411eefeeee389199cef97 100644 (file)
--- a/tools/fit_common.c
+++ b/tools/fit_common.c
@@ -134,7 +134,7 @@ int copyfile(const char *src, const char *dst)
                goto out;
        }
 
-       fd_dst = open(dst, O_WRONLY | O_CREAT, 0666);
+       fd_dst = open(dst, O_WRONLY | O_CREAT | O_TRUNC, 0666);
        if (fd_dst < 0) {
                printf("Can't open file %s (%s)\n", dst, strerror(errno));
                goto out;

diff --git a/tools/fit_common.h b/tools/fit_common.h
index 872d8afa1763b0042fcc41f0a6704ed5a2a216b9..c600dc2ba48a1ef74a5a6ee3bbdad332a066255a 100644 (file)
--- a/tools/fit_common.h
+++ b/tools/fit_common.h
@@ -44,6 +44,8 @@ int mmap_fdt(const char *cmdname, const char *fname, size_t size_inc,
  *
  * This uses read()/write() to copy file @src to file @dst
  *
+ * If @dst exists, it is overwritten and truncated to the correct size.
+ *
  * @src: Filename to read from
  * @dst: Filename to write to
  * @return 0 if OK, -1 on error