Split code out into separate files and remove some global variables to

[rsync/rsync.git] / io.c

diff --git a/io.c b/io.c
index 9c4ac19..ed6a70c 100644 (file)
--- a/io.c
+++ b/io.c
@@ -2,7 +2,7 @@
    
    Copyright (C) 1996-2001 by Andrew Tridgell 
    Copyright (C) Paul Mackerras 1996
-   Copyright (C) 2001 by Martin Pool <mbp@samba.org>
+   Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.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
@@ -19,11 +19,21 @@
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
-/*
-  socket and pipe IO utilities used in rsync 
+/**
+ * @file io.c
+ *
+ * Socket and pipe IO utilities used in rsync.
+ *
+ * rsync provides its own multiplexing system, which is used to send
+ * stderr and stdout over a single socket.  We need this because
+ * stdout normally carries the binary data stream, and stderr all our
+ * error messages.
+ *
+ * For historical reasons this is off during the start of the
+ * connection, but it's switched on quite early using
+ * io_start_multiplex_out() and io_start_multiplex_in().
+ **/
 
-  tridge, June 1996
-  */
 #include "rsync.h"
 
 /* if no timeout is specified then use a 60 second select timeout */
@@ -377,7 +387,8 @@ unsigned char read_byte(int f)
        return c;
 }
 
-/* write len bytes to fd */
+/* Write len bytes to fd.  This underlies the multiplexing system,
+ * which is always called by application code.  */
 static void writefd_unbuffered(int fd,char *buf,size_t len)
 {
        size_t total = 0;
@@ -442,8 +453,11 @@ static void writefd_unbuffered(int fd,char *buf,size_t len)
                        }
 
                        if (ret <= 0) {
-                               rprintf(FERROR,
-                                       "error writing %d unbuffered bytes"
+                               /* Don't try to write errors back
+                                * across the stream */
+                               io_multiplexing_close();
+                               rprintf(FERROR, RSYNC_NAME
+                                       ": error writing %d unbuffered bytes"
                                        " - exiting: %s\n", len,
                                        strerror(errno));
                                exit_cleanup(RERR_STREAMIO);
@@ -527,8 +541,7 @@ void io_flush(void)
 }
 
 
-/* XXX: fd is ignored, which seems a little strange. */
-void io_end_buffering(int fd)
+void io_end_buffering(void)
 {
        io_flush();
        if (!io_multiplexing_out) {
@@ -549,7 +562,7 @@ static void writefd(int fd,char *buf,size_t len)
        }
 
        while (len) {
-               int n = MIN(len, IO_BUFFER_SIZE-io_buffer_count);
+               int n = MIN((int) len, IO_BUFFER_SIZE-io_buffer_count);
                if (n > 0) {
                        memcpy(io_buffer+io_buffer_count, buf, n);
                        buf += n;
@@ -610,12 +623,19 @@ void write_byte(int f,unsigned char c)
 
 
 
+/**
+ * Read a line of up to @p maxlen characters into @p buf.  Does not
+ * contain a trailing newline or carriage return.
+ *
+ * @return 1 for success; 0 for io error or truncation.
+ **/
 int read_line(int f, char *buf, size_t maxlen)
 {
        while (maxlen) {
                buf[0] = 0;
                read_buf(f, buf, 1);
-               if (buf[0] == 0) return 0;
+               if (buf[0] == 0)
+                       return 0;
                if (buf[0] == '\n') {
                        buf[0] = 0;
                        break;