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[rsync/rsync.git] / io.c

diff --git a/io.c b/io.c
index c01296d..3999688 100644 (file)
--- a/io.c
+++ b/io.c
@@ -1,5 +1,6 @@
-/* 
-   Copyright (C) Andrew Tridgell 1996
+/* -*- c-file-style: "linux" -*-
+   
+   Copyright (C) 1996-2000 by Andrew Tridgell 
    Copyright (C) Paul Mackerras 1996
    
    This program is free software; you can redistribute it and/or modify
@@ -27,6 +28,8 @@
 /* if no timeout is specified then use a 60 second select timeout */
 #define SELECT_TIMEOUT 60
 
+extern int bwlimit;
+
 static int io_multiplexing_out;
 static int io_multiplexing_in;
 static int multiplex_in_fd;
@@ -37,18 +40,13 @@ extern int verbose;
 extern int io_timeout;
 extern struct stats stats;
 
-static int buffer_f_in = -1;
 static int io_error_fd = -1;
 
 static void read_loop(int fd, char *buf, int len);
 
-void setup_readbuffer(int f_in)
-{
-       buffer_f_in = f_in;
-}
-
 static void check_timeout(void)
 {
+       extern int am_server, am_daemon;
        time_t t;
        
        if (!io_timeout) return;
@@ -61,8 +59,10 @@ static void check_timeout(void)
        t = time(NULL);
 
        if (last_io && io_timeout && (t-last_io) >= io_timeout) {
-               rprintf(FERROR,"io timeout after %d second - exiting\n", 
-                       (int)(t-last_io));
+               if (!am_server && !am_daemon) {
+                       rprintf(FERROR,"io timeout after %d second - exiting\n", 
+                               (int)(t-last_io));
+               }
                exit_cleanup(RERR_TIMEOUT);
        }
 }
@@ -104,9 +104,15 @@ static void read_error_fd(void)
 
 static int no_flush;
 
-/* read from a socket with IO timeout. return the number of
-   bytes read. If no bytes can be read then exit, never return
-   a number <= 0 */
+/*
+ * Read from a socket with IO timeout. return the number of bytes
+ * read. If no bytes can be read then exit, never return a number <= 0.
+ *
+ * TODO: If the remote shell connection fails, then current versions actually
+ * report an "unexpected EOF" error here.  Since it's a fairly common mistake
+ * to try to use rsh when ssh is required, we should trap that: if we fail
+ * to read any data at all, we should give a better explanation.
+ */
 static int read_timeout(int fd, char *buf, int len)
 {
        int n, ret=0;
@@ -159,6 +165,11 @@ static int read_timeout(int fd, char *buf, int len)
                        continue;
                }
 
+               if (n == -1 && 
+                   (errno == EWOULDBLOCK || errno == EAGAIN)) {
+                       continue;
+               }
+
 
                if (n == 0) {
                        if (eof_error) {
@@ -313,11 +324,7 @@ unsigned char read_byte(int f)
        return c;
 }
 
-
-
-/* write len bytes to fd, possibly reading from buffer_f_in if set
-   in order to unclog the pipe. don't return until all len
-   bytes have been written */
+/* write len bytes to fd */
 static void writefd_unbuffered(int fd,char *buf,int len)
 {
        int total = 0;
@@ -364,19 +371,36 @@ static void writefd_unbuffered(int fd,char *buf,int len)
                if (FD_ISSET(fd, &w_fds)) {
                        int ret, n = len-total;
                        
-                       if (n > PIPE_BUF) n = PIPE_BUF;
-
-                       ret = write(fd,buf+total,n?n:1);
+                       ret = write(fd,buf+total,n);
 
                        if (ret == -1 && errno == EINTR) {
                                continue;
                        }
 
+                       if (ret == -1 && 
+                           (errno == EWOULDBLOCK || errno == EAGAIN)) {
+                               msleep(1);
+                               continue;
+                       }
+
                        if (ret <= 0) {
                                rprintf(FERROR,"erroring writing %d bytes - exiting\n", len);
                                exit_cleanup(RERR_STREAMIO);
                        }
 
+                       /* Sleep after writing to limit I/O bandwidth */
+                       if (bwlimit)
+                       {
+                           tv.tv_sec = 0;
+                           tv.tv_usec = ret * 1000 / bwlimit;
+                           while (tv.tv_usec > 1000000)
+                           {
+                               tv.tv_sec++;
+                               tv.tv_usec -= 1000000;
+                           }
+                           select(0, NULL, NULL, NULL, &tv);
+                       }
+ 
                        total += ret;
 
                        if (io_timeout)
@@ -409,8 +433,8 @@ static void mplex_write(int fd, enum logcode code, char *buf, int len)
 
        SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
 
-       if (n > (sizeof(buf)-4)) {
-               n = sizeof(buf)-4;
+       if (n > (sizeof(buffer)-4)) {
+               n = sizeof(buffer)-4;
        }
 
        memcpy(&buffer[4], buf, n);
@@ -419,7 +443,9 @@ static void mplex_write(int fd, enum logcode code, char *buf, int len)
        len -= n;
        buf += n;
 
-       writefd_unbuffered(fd, buf, len);
+       if (len) {
+               writefd_unbuffered(fd, buf, len);
+       }
 }
 
 
@@ -436,6 +462,8 @@ void io_flush(void)
        io_buffer_count = 0;
 }
 
+
+/* XXX: fd is ignored, which seems a little strange. */
 void io_end_buffering(int fd)
 {
        io_flush();
@@ -445,6 +473,17 @@ void io_end_buffering(int fd)
        }
 }
 
+/* some OSes have a bug where an exit causes the pending writes on
+   a socket to be flushed. Do an explicit shutdown to try to prevent this */
+void io_shutdown(void)
+{
+       if (multiplex_out_fd != -1) close(multiplex_out_fd);
+       if (io_error_fd != -1) close(io_error_fd);
+       multiplex_out_fd = -1;
+       io_error_fd = -1;
+}
+
+
 static void writefd(int fd,char *buf,int len)
 {
        stats.total_written += len;
@@ -475,6 +514,11 @@ void write_int(int f,int32 x)
        writefd(f,b,4);
 }
 
+
+/*
+ * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
+ * 64-bit types on this platform.
+ */
 void write_longint(int f, int64 x)
 {
        extern int remote_version;
@@ -595,7 +639,3 @@ void io_multiplexing_close(void)
        io_multiplexing_out = 0;
 }
 
-void io_close_input(int fd)
-{
-       buffer_f_in = -1;
-}