commit 65e37b4a128e5c4fe88721c790fd6f5c13102a62
author Gleb Smirnoff <glebius@nginx.com> Thu Aug 08 15:06:39 2013 +0400
committer Gleb Smirnoff <glebius@nginx.com> Thu Aug 08 15:06:39 2013 +0400
tree 13df7393a0d4f489ca50b6541e49cfb7a6bf09bb
parent be27365bb10e255330d3baeda2b918ea9fd79b8e

Don't lose pointer to first nonempty buf in ngx_*_sendfile_chain().

In ngx_*_sendfile_chain() when calculating pointer to a first
non-zero sized buf, use "in" as iterator.  This fixes processing
of zero sized buf(s) after EINTR.  Otherwise function can return
zero sized buf to caller, and later ngx_http_write_filter()
logs warning.

src/os/unix/ngx_solaris_sendfilev_chain.c

diff --git a/src/os/unix/ngx_solaris_sendfilev_chain.c b/src/os/unix/ngx_solaris_sendfilev_chain.c
index 520eaaa..37bb09d 100644
--- a/src/os/unix/ngx_solaris_sendfilev_chain.c
+++ b/src/os/unix/ngx_solaris_sendfilev_chain.c
@@ -207,9 +207,9 @@
 
         c->sent += sent;
 
-        for (cl = in; cl; cl = cl->next) {
+        for ( /* void */ ; in; in = in->next) {
 
-            if (ngx_buf_special(cl->buf)) {
+            if (ngx_buf_special(in->buf)) {
                 continue;
             }
 
@@ -217,28 +217,28 @@
                 break;
             }
 
-            size = ngx_buf_size(cl->buf);
+            size = ngx_buf_size(in->buf);
 
             if ((off_t) sent >= size) {
                 sent = (size_t) ((off_t) sent - size);
 
-                if (ngx_buf_in_memory(cl->buf)) {
-                    cl->buf->pos = cl->buf->last;
+                if (ngx_buf_in_memory(in->buf)) {
+                    in->buf->pos = in->buf->last;
                 }
 
-                if (cl->buf->in_file) {
-                    cl->buf->file_pos = cl->buf->file_last;
+                if (in->buf->in_file) {
+                    in->buf->file_pos = in->buf->file_last;
                 }
 
                 continue;
             }
 
-            if (ngx_buf_in_memory(cl->buf)) {
-                cl->buf->pos += sent;
+            if (ngx_buf_in_memory(in->buf)) {
+                in->buf->pos += sent;
             }
 
-            if (cl->buf->in_file) {
-                cl->buf->file_pos += sent;
+            if (in->buf->in_file) {
+                in->buf->file_pos += sent;
             }
 
             break;
@@ -250,13 +250,11 @@
 
         if (!complete) {
             wev->ready = 0;
-            return cl;
+            return in;
         }
 
-        if (send >= limit || cl == NULL) {
-            return cl;
+        if (send >= limit || in == NULL) {
+            return in;
         }
-
-        in = cl;
     }
 }