fix FAST_FUNC fallout

[oweals/busybox.git] / libbb / copyfd.c

diff --git a/libbb/copyfd.c b/libbb/copyfd.c
index e9300a97d53ce3ba414bcf8e6a18a5ff31172153..c5f8b5b8763a12437be5e74607e5587e67bde9d3 100644 (file)
--- a/libbb/copyfd.c
+++ b/libbb/copyfd.c
@@ -7,60 +7,94 @@
  * 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 "libbb.h"
 
+/* Used by NOFORK applets (e.g. cat) - must not use xmalloc */
+
+static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
+{
+       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 BUFSIZ < 4096
-#undef BUFSIZ
-#define BUFSIZ 4096
+       /* 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;
 
-static ssize_t bb_full_fd_action(int src_fd, int dst_fd, size_t size)
-{
-       int status = -1;
-       size_t total = 0;
-       RESERVE_CONFIG_BUFFER(buffer,BUFSIZ);
+       if (!size) {
+               size = buffer_size;
+               status = 1; /* copy until eof */
+       }
 
-       if (src_fd < 0) goto out;
-       while (!size || total < size) {
-               ssize_t wr, rd;
+       while (1) {
+               ssize_t rd;
 
-               rd = safe_read(src_fd, buffer,
-                               (!size || size - total > BUFSIZ) ? BUFSIZ : size - total);
+               rd = safe_read(src_fd, buffer, size > buffer_size ? buffer_size : size);
 
-               if (rd > 0) {
-                       /* A -1 dst_fd means we need to fake it... */
-                       wr = (dst_fd < 0) ? rd : full_write(dst_fd, buffer, rd);
+               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;
                        }
-                       total += wr;
-                       if (total == size) status = 0;
-               } else if (rd < 0) {
-                       bb_perror_msg(bb_msg_read_error);
-                       break;
-               } else if (rd == 0) {
-                       /* All done. */
-                       status = 0;
-                       break;
+               }
+               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:
 
-out:
-       RELEASE_CONFIG_BUFFER(buffer);
-
-       return status ? status : (ssize_t)total;
+#if CONFIG_FEATURE_COPYBUF_KB > 4
+       if (buffer_size != 4 * 1024)
+               munmap(buffer, buffer_size);
+#endif
+       return status ? -1 : total;
 }
 
 
-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);
@@ -68,7 +102,18 @@ int bb_copyfd_size(int fd1, int fd2, const off_t size)
        return 0;
 }
 
-int bb_copyfd_eof(int fd1, int fd2)
+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();
+}
+
+off_t FAST_FUNC bb_copyfd_eof(int fd1, int fd2)
 {
        return bb_full_fd_action(fd1, fd2, 0);
 }