[svn] New option `--limit-rate'.

[wget] / src / retr.c

diff --git a/src/retr.c b/src/retr.c
index b8fb6c84b3a05e348a2784705294890438f7a670..9930cc1e0f4782bf27eea814672329ca344e2696 100644 (file)
--- a/src/retr.c
+++ b/src/retr.c
@@ -52,6 +52,50 @@ extern int errno;
 int global_download_count;
 
 \f
+static struct {
+  long bytes;
+  long dltime;
+} limit_data;
+
+static void
+limit_bandwidth_reset (void)
+{
+  limit_data.bytes  = 0;
+  limit_data.dltime = 0;
+}
+
+/* Limit the bandwidth by pausing the download for an amount of time.
+   BYTES is the number of bytes received from the network, DELTA is
+   how long it took to receive them, DLTIME the current download time,
+   TIMER the timer, and ADJUSTMENT the previous.  */
+
+static void
+limit_bandwidth (long bytes, long delta)
+{
+  long expected;
+
+  limit_data.bytes += bytes;
+  limit_data.dltime += delta;
+
+  expected = (long)(1000.0 * limit_data.bytes / opt.limit_rate);
+
+  if (expected > limit_data.dltime)
+    {
+      long slp = expected - limit_data.dltime;
+      if (slp < 200)
+       {
+         DEBUGP (("deferring a %ld ms sleep (%ld/%ld) until later.\n",
+                  slp, limit_data.bytes, limit_data.dltime));
+         return;
+       }
+      DEBUGP (("sleeping %ld ms\n", slp));
+      usleep (1000 * slp);
+    }
+
+  limit_data.bytes = 0;
+  limit_data.dltime = 0;
+}
+
 #define MIN(i, j) ((i) <= (j) ? (i) : (j))
 
 /* Reads the contents of file descriptor FD, until it is closed, or a
@@ -77,33 +121,43 @@ int global_download_count;
    from fd immediately, flush or discard the buffer.  */
 int
 get_contents (int fd, FILE *fp, long *len, long restval, long expected,
-             struct rbuf *rbuf, int use_expected)
+             struct rbuf *rbuf, int use_expected, long *elapsed)
 {
   int res = 0;
   static char c[8192];
   void *progress = NULL;
+  struct wget_timer *timer = wtimer_allocate ();
+  long dltime = 0, last_dltime = 0;
 
   *len = restval;
+
   if (opt.verbose)
     progress = progress_create (restval, expected);
 
   if (rbuf && RBUF_FD (rbuf) == fd)
     {
-      int need_flush = 0;
+      int sz = 0;
       while ((res = rbuf_flush (rbuf, c, sizeof (c))) != 0)
        {
-         if (fwrite (c, sizeof (char), res, fp) < res)
-           return -2;
-         if (opt.verbose)
-           progress_update (progress, res);
+         fwrite (c, sizeof (char), res, fp);
          *len += res;
-         need_flush = 1;
+         sz += res;
        }
-      if (need_flush)
+      if (sz)
        fflush (fp);
       if (ferror (fp))
-       return -2;
+       {
+         res = -2;
+         goto out;
+       }
+      if (opt.verbose)
+       progress_update (progress, sz, 0);
     }
+
+  if (opt.limit_rate)
+    limit_bandwidth_reset ();
+  wtimer_reset (timer);
+
   /* Read from fd while there is available data.
 
      Normally, if expected is 0, it means that it is not known how
@@ -115,14 +169,12 @@ get_contents (int fd, FILE *fp, long *len, long restval, long expected,
                            ? MIN (expected - *len, sizeof (c))
                            : sizeof (c));
 #ifdef HAVE_SSL
-               if (rbuf->ssl!=NULL) {
-                 res = ssl_iread (rbuf->ssl, c, amount_to_read);
-               } else {
-#endif /* HAVE_SSL */
-                 res = iread (fd, c, amount_to_read);
-#ifdef HAVE_SSL
-               }
+      if (rbuf->ssl!=NULL)
+       res = ssl_iread (rbuf->ssl, c, amount_to_read);
+      else
 #endif /* HAVE_SSL */
+       res = iread (fd, c, amount_to_read);
+
       if (res > 0)
        {
          fwrite (c, sizeof (char), res, fp);
@@ -131,9 +183,23 @@ get_contents (int fd, FILE *fp, long *len, long restval, long expected,
             packets typically won't be too tiny anyway.  */
          fflush (fp);
          if (ferror (fp))
-           return -2;
+           {
+             res = -2;
+             goto out;
+           }
+
+         /* If bandwidth is not limited, one call to wtimer_elapsed
+            is sufficient.  */
+         dltime = wtimer_elapsed (timer);
+         if (opt.limit_rate)
+           {
+             limit_bandwidth (res, dltime - last_dltime);
+             dltime = wtimer_elapsed (timer);
+             last_dltime = dltime;
+           }
+
          if (opt.verbose)
-           progress_update (progress, res);
+           progress_update (progress, res, dltime);
          *len += res;
        }
       else
@@ -141,8 +207,14 @@ get_contents (int fd, FILE *fp, long *len, long restval, long expected,
     }
   if (res < -1)
     res = -1;
+
+ out:
   if (opt.verbose)
-    progress_finish (progress);
+    progress_finish (progress, dltime);
+  if (elapsed)
+    *elapsed = dltime;
+  wtimer_delete (timer);
+
   return res;
 }
 \f
@@ -427,13 +499,21 @@ retrieve_url (const char *origurl, char **file, char **newloc,
     FREE_MAYBE (local_file);
 
   url_free (u);
-  if (redirections)
-    string_set_free (redirections);
 
-  if (newloc)
-    *newloc = url;
+  if (redirections)
+    {
+      string_set_free (redirections);
+      if (newloc)
+       *newloc = url;
+      else
+       xfree (url);
+    }
   else
-    xfree (url);
+    {
+      if (newloc)
+       *newloc = NULL;
+      xfree (url);
+    }
 
   ++global_download_count;