Here's a revised patch to provide error returning copy-file as well as
error-raising copy-file.
Of particular interest:
1. What would you like to call the new function?
2. I haven't yet added a test; from looking at the tests for copy-file
it seems it should suffice to add a call to remove followed by an
asserted call to copy_file_preserving_error (or whatever it's called)
after the call to copy_file_preserving, i.e. just repeat the copy with
the other version of the function.
diff --git a/lib/copy-file.c b/lib/copy-file.c
index f9cd9c0..4ae8427 100644
--- a/lib/copy-file.c
+++ b/lib/copy-file.c
@@ -53,47 +53,79 @@
enum { IO_SIZE = 32 * 1024 };
-void
-copy_file_preserving (const char *src_filename, const char *dest_filename)
+enum {
+ ERR_OPEN_READ = 1,
+ ERR_OPEN_BACKUP_WRITE,
+ ERR_READ,
+ ERR_WRITE,
+ ERR_AFTER_READ,
+ ERR_ACL
+};
+
+
+int
+_copy_file_preserving (const char *src_filename, const char *dest_filename)
{
int src_fd;
struct stat statbuf;
int mode;
int dest_fd;
+ int err = 0;
char *buf = xmalloc (IO_SIZE);
src_fd = open (src_filename, O_RDONLY | O_BINARY);
- if (src_fd < 0 || fstat (src_fd, &statbuf) < 0)
- error (EXIT_FAILURE, errno, _("error while opening \"%s\" for reading"),
- src_filename);
+ if (src_fd < 0)
+ {
+ err = ERR_OPEN_READ;
+ goto error;
+ }
+ if (fstat (src_fd, &statbuf) < 0)
+ {
+ err = ERR_OPEN_READ;
+ goto error_src;
+ }
mode = statbuf.st_mode & 07777;
dest_fd = open (dest_filename, O_WRONLY | O_CREAT | O_TRUNC |
O_BINARY, 0600);
if (dest_fd < 0)
- error (EXIT_FAILURE, errno, _("cannot open backup file \"%s\" for
writing"),
- dest_filename);
+ {
+ err = ERR_OPEN_BACKUP_WRITE;
+ goto error_src;
+ }
/* Copy the file contents. */
for (;;)
{
size_t n_read = safe_read (src_fd, buf, IO_SIZE);
if (n_read == SAFE_READ_ERROR)
- error (EXIT_FAILURE, errno, _("error reading \"%s\""), src_filename);
+ {
+ err = ERR_READ;
+ goto error_src_dest;
+ }
if (n_read == 0)
break;
if (full_write (dest_fd, buf, n_read) < n_read)
- error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
+ {
+ err = ERR_WRITE;
+ goto error_src_dest;
+ }
}
free (buf);
#if !USE_ACL
if (close (dest_fd) < 0)
- error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
+ {
+ err = ERR_WRITE;
+ goto error_src;
+ }
if (close (src_fd) < 0)
- error (EXIT_FAILURE, errno, _("error after reading \"%s\""), src_filename);
+ {
+ err = ERR_AFTER_READ;
+ goto error;
+ }
#endif
/* Preserve the access and modification times. */
@@ -123,15 +155,73 @@ copy_file_preserving (const char *src_filename,
const char *dest_filename)
/* Preserve the access permissions. */
#if USE_ACL
if (copy_acl (src_filename, src_fd, dest_filename, dest_fd, mode))
- exit (EXIT_FAILURE);
+ {
+ err = ERR_ACL;
+ goto error_src_dest;
+ }
#else
chmod (dest_filename, mode);
#endif
#if USE_ACL
if (close (dest_fd) < 0)
- error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
+ {
+ err = ERR_WRITE;
+ goto error_src;
+ }
if (close (src_fd) < 0)
- error (EXIT_FAILURE, errno, _("error after reading \"%s\""), src_filename);
+ {
+ err = ERR_AFTER_READ;
+ goto error;
+ }
#endif
+
+ return 0;
+
+ error_src_dest:
+ close (dest_fd);
+ error_src:
+ close (src_fd);
+ error:
+ return -err;
+}
+
+void
+copy_file_preserving (const char *src_filename, const char *dest_filename)
+{
+ switch (_copy_file_preserving (src_filename, dest_filename))
+ {
+ case 0:
+ return;
+
+ case ERR_OPEN_READ:
+ error (EXIT_FAILURE, errno, _("error while opening \"%s\" for reading"),
+ src_filename);
+
+ case ERR_OPEN_BACKUP_WRITE:
+ error (EXIT_FAILURE, errno, _("cannot open backup file \"%s\"
for writing"),
+ dest_filename);
+
+ case ERR_READ:
+ error (EXIT_FAILURE, errno, _("error reading \"%s\""), src_filename);
+
+ case ERR_WRITE:
+ error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
+
+ case ERR_AFTER_READ:
+ error (EXIT_FAILURE, errno, _("error after reading \"%s\""),
src_filename);
+
+ case ERR_ACL:
+ exit (EXIT_FAILURE);
+
+ default:
+ exit (EXIT_FAILURE);
+ }
+}
+
+
+int
+copy_file_preserving_error (const char *src_filename, const char
*dest_filename)
+{
+ return _copy_file_preserving (src_filename, dest_filename) < 0 ? - 1 : 0;
}
diff --git a/lib/copy-file.h b/lib/copy-file.h
index cb8b1f7..0f0931c 100644
--- a/lib/copy-file.h
+++ b/lib/copy-file.h
@@ -28,6 +28,9 @@ extern "C" {
Exit upon failure. */
extern void copy_file_preserving (const char *src_filename, const
char *dest_filename);
+/* Error-returning version of copy_file_preserving. */
+extern int copy_file_preserving_error (const char *src_filename,
const char *dest_filename);
+
#ifdef __cplusplus
}
