Bump to version 1.22.1

[platform/upstream/busybox.git] / libbb / copyfd.c

diff --git a/libbb/copyfd.c b/libbb/copyfd.c
index aa938d1..eda2747 100644 (file)
--- a/libbb/copyfd.c
+++ b/libbb/copyfd.c
@@ -2,58 +2,134 @@
 /*
  * Utility routines.
  *
- * Copyright (C) 1999-2001 Erik Andersen <andersee@debian.org>
+ * Copyright (C) 1999-2005 by Erik Andersen <andersen@codepoet.org>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include <unistd.h>
-#include <string.h>
-#include <errno.h>
 #include "libbb.h"
 
-
-extern int copyfd(int fd1, int fd2)
+/* Used by NOFORK applets (e.g. cat) - must not use xmalloc.
+ * size < 0 means "ignore write errors", used by tar --to-command
+ * size = 0 means "copy till EOF"
+ */
+static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
 {
-       char buf[8192];
-       ssize_t nread, nwrote;
+       int status = -1;
+       off_t total = 0;
+       bool continue_on_write_error = 0;
+#if CONFIG_FEATURE_COPYBUF_KB <= 4
+       char buffer[CONFIG_FEATURE_COPYBUF_KB * 1024];
+       enum { buffer_size = sizeof(buffer) };
+#else
+       char *buffer;
+       int buffer_size;
+#endif
+
+       if (size < 0) {
+               size = -size;
+               continue_on_write_error = 1;
+       }
+
+#if CONFIG_FEATURE_COPYBUF_KB > 4
+       if (size > 0 && size <= 4 * 1024)
+               goto use_small_buf;
+       /* We want page-aligned buffer, just in case kernel is clever
+        * and can do page-aligned io more efficiently */
+       buffer = mmap(NULL, CONFIG_FEATURE_COPYBUF_KB * 1024,
+                       PROT_READ | PROT_WRITE,
+                       MAP_PRIVATE | MAP_ANON,
+                       /* ignored: */ -1, 0);
+       buffer_size = CONFIG_FEATURE_COPYBUF_KB * 1024;
+       if (buffer == MAP_FAILED) {
+ use_small_buf:
+               buffer = alloca(4 * 1024);
+               buffer_size = 4 * 1024;
+       }
+#endif
+
+       if (src_fd < 0)
+               goto out;
+
+       if (!size) {
+               size = buffer_size;
+               status = 1; /* copy until eof */
+       }
 
        while (1) {
-               nread = safe_read(fd1, buf, sizeof(buf));
-               if (nread == 0)
+               ssize_t rd;
+
+               rd = safe_read(src_fd, buffer, size > buffer_size ? buffer_size : size);
+
+               if (!rd) { /* eof - all done */
+                       status = 0;
                        break;
-               if (nread == -1) {
-                       perror_msg("read");
-                       return -1;
                }
-
-               nwrote = full_write(fd2, buf, nread);
-               if (nwrote == -1) {
-                       perror_msg("write");
-                       return -1;
+               if (rd < 0) {
+                       bb_perror_msg(bb_msg_read_error);
+                       break;
+               }
+               /* dst_fd == -1 is a fake, else... */
+               if (dst_fd >= 0) {
+                       ssize_t wr = full_write(dst_fd, buffer, rd);
+                       if (wr < rd) {
+                               if (!continue_on_write_error) {
+                                       bb_perror_msg(bb_msg_write_error);
+                                       break;
+                               }
+                               dst_fd = -1;
+                       }
+               }
+               total += rd;
+               if (status < 0) { /* if we aren't copying till EOF... */
+                       size -= rd;
+                       if (!size) {
+                               /* 'size' bytes copied - all done */
+                               status = 0;
+                               break;
+                       }
                }
        }
+ out:
+
+#if CONFIG_FEATURE_COPYBUF_KB > 4
+       if (buffer_size != 4 * 1024)
+               munmap(buffer, buffer_size);
+#endif
+       return status ? -1 : total;
+}
+
 
+#if 0
+void FAST_FUNC complain_copyfd_and_die(off_t sz)
+{
+       if (sz != -1)
+               bb_error_msg_and_die("short read");
+       /* if sz == -1, bb_copyfd_XX already complained */
+       xfunc_die();
+}
+#endif
+
+off_t FAST_FUNC bb_copyfd_size(int fd1, int fd2, off_t size)
+{
+       if (size) {
+               return bb_full_fd_action(fd1, fd2, size);
+       }
        return 0;
 }
 
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+void FAST_FUNC bb_copyfd_exact_size(int fd1, int fd2, off_t size)
+{
+       off_t sz = bb_copyfd_size(fd1, fd2, size);
+       if (sz == (size >= 0 ? size : -size))
+               return;
+       if (sz != -1)
+               bb_error_msg_and_die("short read");
+       /* if sz == -1, bb_copyfd_XX already complained */
+       xfunc_die();
+}
+
+off_t FAST_FUNC bb_copyfd_eof(int fd1, int fd2)
+{
+       return bb_full_fd_action(fd1, fd2, 0);
+}