Merge copyfd and copy_file_chunk

git-svn-id: svn://busybox.net/trunk/busybox@6208 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 42 insertions, 15 deletions

diff --git a/libbb/copyfd.c b/libbb/copyfd.c
index 22d8c3996..4df1fd084 100644
--- a/libbb/copyfd.c
+++ b/libbb/copyfd.c
@@ -24,27 +24,54 @@
 #include <errno.h>
 #include "libbb.h"
 
-
-extern int copyfd(int fd1, int fd2)
+/* If chunksize is 0 copy untill EOF */
+extern int copyfd(int fd1, int fd2, const off_t chunksize)
 {
-        char buf[8192];
-        ssize_t nread, nwrote;
+        size_t nread;
+        size_t nwritten;
+        size_t size;
+        size_t remaining;
+        char buffer[BUFSIZ];
+
+        if (chunksize) {
+                remaining = chunksize;
+        } else {
+                remaining = -1;
+        }
+
+        do {
+                if ((chunksize > BUFSIZ) || (chunksize == 0)) {
+                        size = BUFSIZ;
+                } else {
+                        size = chunksize;
+                }
+
+                nread = safe_read(fd1, buffer, size);
 
-        while (1) {
-                nread = safe_read(fd1, buf, sizeof(buf));
-                if (nread == 0)
-                        break;
                 if (nread == -1) {
-                        perror_msg("read");
-                        return -1;
+                        perror_msg("read failure");
+                        return(-1);
                 }
+                else if (nread == 0) {
+                        if (chunksize) {
+                                error_msg("Unable to read all data");
+                                return(-1);
+                        } else {
+                                return(0);
+                        }
+                }
+
+                nwritten = full_write(fd2, buffer, nread);
 
-                nwrote = full_write(fd2, buf, nread);
-                if (nwrote == -1) {
-                        perror_msg("write");
-                        return -1;
+                if (nwritten != nread) {
+                        error_msg("Unable to write all data");
+                        return(-1);
                 }
-        }
+
+                if (chunksize) {
+                        remaining -= nwritten;
+                }
+        } while (remaining != 0);
 
         return 0;
 }