fix FAST_FUNC fallout
[oweals/busybox.git] / libbb / copyfd.c
index baf99df51949ca3da997bdb7d98c7f26022d47ab..c5f8b5b8763a12437be5e74607e5587e67bde9d3 100644 (file)
  *
  * 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 tarball for details.
  */
 
-#include <errno.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "busybox.h"
 #include "libbb.h"
 
+/* Used by NOFORK applets (e.g. cat) - must not use xmalloc */
 
-#if BUFSIZ < 4096
-#undef BUFSIZ
-#define BUFSIZ 4096
-#endif
-
-
-static size_t bb_full_fd_action(int src_fd, int dst_fd, const size_t size2)
+static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
 {
-       int status;
-       size_t xread, wrote, total, size = size2;
+       int status = -1;
+       off_t total = 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;
 
-       if ((dst_fd < 0) || (src_fd < 0)) {
-               return -1;
+       /* 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) {
+               buffer = alloca(4 * 1024);
+               buffer_size = 4 * 1024;
        }
+#endif
+
+       if (src_fd < 0)
+               goto out;
 
-       if (size == 0) {
-               /* If size is 0 copy until EOF */
-               size = ULONG_MAX;
+       if (!size) {
+               size = buffer_size;
+               status = 1; /* copy until eof */
        }
 
-       {
-               RESERVE_CONFIG_BUFFER(buffer,BUFSIZ);
-               total = 0;
-               wrote = 0;
-               status = -1;
-               while (total < size)
-               {
-                       xread = BUFSIZ;
-                       if (size < (wrote + BUFSIZ))
-                               xread = size - wrote;
-                       xread = bb_full_read(src_fd, buffer, xread);
-                       if (xread > 0) {
-                               wrote = bb_full_write(dst_fd, buffer, xread);
-                               if (wrote < xread) {
-                                       bb_perror_msg(bb_msg_write_error);
-                                       break;
-                               }
-                               total += wrote;
-                       } else if (xread < 0) {
-                               bb_perror_msg(bb_msg_read_error);
+       while (1) {
+               ssize_t rd;
+
+               rd = safe_read(src_fd, buffer, size > buffer_size ? buffer_size : size);
+
+               if (!rd) { /* eof - all done */
+                       status = 0;
+                       break;
+               }
+               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) {
+                               bb_perror_msg(bb_msg_write_error);
                                break;
-                       } else if (xread == 0) {
-                               /* All done. */
+                       }
+               }
+               total += rd;
+               if (status < 0) { /* if we aren't copying till EOF... */
+                       size -= rd;
+                       if (!size) {
+                               /* 'size' bytes copied - all done */
                                status = 0;
                                break;
                        }
                }
-               RELEASE_CONFIG_BUFFER(buffer);
        }
+ out:
 
-       if (status == 0 || wrote)
-               return wrote;
-       /* Some sortof error occured */
-       return -1;
+#if CONFIG_FEATURE_COPYBUF_KB > 4
+       if (buffer_size != 4 * 1024)
+               munmap(buffer, buffer_size);
+#endif
+       return status ? -1 : total;
 }
 
 
-extern int bb_copyfd_size(int fd1, int fd2, const off_t size)
+#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 bb_full_fd_action(fd1, fd2, size);
        }
-       return(0);
+       return 0;
+}
+
+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)
+               return;
+       if (sz != -1)
+               bb_error_msg_and_die("short read");
+       /* if sz == -1, bb_copyfd_XX already complained */
+       xfunc_die();
 }
 
-extern int bb_copyfd_eof(int fd1, int fd2)
+off_t FAST_FUNC bb_copyfd_eof(int fd1, int fd2)
 {
-       return(bb_full_fd_action(fd1, fd2, 0));
+       return bb_full_fd_action(fd1, fd2, 0);
 }