[PATCH] commands: truncate: report errors from ftruncate()

[Ahmad Fatoum]

From: Ahmad Fatoum <a.fat...@barebox.org>

ftruncate() and fstat() return a negative error code, not -1, so the
command only noticed an -EPERM and otherwise exited with 0 even when the
file wasn't resized, e.g. on a size ubootvarfs has no room for.

Let's check for any negative return value instead.

Fixes: f59a9574c22c ("commands: add new truncate command")
Assisted-by: Claude:opus-5.5
Signed-off-by: Ahmad Fatoum <a.fat...@barebox.org>
---
 commands/truncate.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/commands/truncate.c b/commands/truncate.c
index 1fd929337dd5..01d827007554 100644
--- a/commands/truncate.c
+++ b/commands/truncate.c
@@ -64,7 +64,7 @@ static int do_truncate(int argc, char *argv[])
                if (modify) {
                        struct stat st;
 
-                       if (fstat(fd, &st) == -1) {
+                       if (fstat(fd, &st) < 0) {
                                perror("fstat");
                                ret = 1;
                                close(fd);
@@ -74,7 +74,7 @@ static int do_truncate(int argc, char *argv[])
                        target_size = st.st_size + size;
                }
 
-               if (ftruncate(fd, target_size) == -1) {
+               if (ftruncate(fd, target_size) < 0) {
                        perror("truncate");
                        ret = 1;
                }
-- 
2.47.3