# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1334653995 0
# Node ID 089cc5154c1e75a96d17dbef65a4edd98a23ecce
# Parent  6cd5d4a279d68b4d41ace7c2d501cf7975afe0cb
IOV_MAX handling microoptimization.

We now stop on IOV_MAX iovec entries only if we are going to add new one,
i.e. next buffer can't be coalesced into last iovec.

This also fixes incorrect checks for trailer creation on FreeBSD and
Mac OS X, header.nelts was checked instead of trailer.nelts.

diff --git a/src/os/unix/ngx_darwin_sendfile_chain.c b/src/os/unix/ngx_darwin_sendfile_chain.c
--- a/src/os/unix/ngx_darwin_sendfile_chain.c
+++ b/src/os/unix/ngx_darwin_sendfile_chain.c
@@ -103,10 +103,8 @@ ngx_darwin_sendfile_chain(ngx_connection
         prev = NULL;
         iov = NULL;
 
-        for (cl = in;
-             cl && header.nelts < IOV_MAX && send < limit;
-             cl = cl->next)
-        {
+        for (cl = in; cl && send < limit; cl = cl->next) {
+
             if (ngx_buf_special(cl->buf)) {
                 continue;
             }
@@ -125,6 +123,10 @@ ngx_darwin_sendfile_chain(ngx_connection
                 iov->iov_len += (size_t) size;
 
             } else {
+                if (header.nelts >= IOV_MAX) {
+                    break;
+                }
+
                 iov = ngx_array_push(&header);
                 if (iov == NULL) {
                     return NGX_CHAIN_ERROR;
@@ -178,7 +180,7 @@ ngx_darwin_sendfile_chain(ngx_connection
             prev = NULL;
             iov = NULL;
 
-            while (cl && header.nelts < IOV_MAX && send < limit) {
+            while (cl && send < limit) {
 
                 if (ngx_buf_special(cl->buf)) {
                     cl = cl->next;
@@ -199,6 +201,10 @@ ngx_darwin_sendfile_chain(ngx_connection
                     iov->iov_len += (size_t) size;
 
                 } else {
+                    if (trailer.nelts >= IOV_MAX) {
+                        break;
+                    }
+
                     iov = ngx_array_push(&trailer);
                     if (iov == NULL) {
                         return NGX_CHAIN_ERROR;
diff --git a/src/os/unix/ngx_freebsd_sendfile_chain.c b/src/os/unix/ngx_freebsd_sendfile_chain.c
--- a/src/os/unix/ngx_freebsd_sendfile_chain.c
+++ b/src/os/unix/ngx_freebsd_sendfile_chain.c
@@ -107,10 +107,8 @@ ngx_freebsd_sendfile_chain(ngx_connectio
         prev = NULL;
         iov = NULL;
 
-        for (cl = in;
-             cl && header.nelts < IOV_MAX && send < limit;
-             cl = cl->next)
-        {
+        for (cl = in; cl && send < limit; cl = cl->next) {
+
             if (ngx_buf_special(cl->buf)) {
                 continue;
             }
@@ -129,6 +127,10 @@ ngx_freebsd_sendfile_chain(ngx_connectio
                 iov->iov_len += (size_t) size;
 
             } else {
+                if (header.nelts >= IOV_MAX){
+                    break;
+                }
+
                 iov = ngx_array_push(&header);
                 if (iov == NULL) {
                     return NGX_CHAIN_ERROR;
@@ -183,7 +185,7 @@ ngx_freebsd_sendfile_chain(ngx_connectio
             prev = NULL;
             iov = NULL;
 
-            while (cl && header.nelts < IOV_MAX && send < limit) {
+            while (cl && send < limit) {
 
                 if (ngx_buf_special(cl->buf)) {
                     cl = cl->next;
@@ -204,6 +206,10 @@ ngx_freebsd_sendfile_chain(ngx_connectio
                     iov->iov_len += (size_t) size;
 
                 } else {
+                    if (trailer.nelts >= IOV_MAX){
+                        break;
+                    }
+
                     iov = ngx_array_push(&trailer);
                     if (iov == NULL) {
                         return NGX_CHAIN_ERROR;
diff --git a/src/os/unix/ngx_linux_sendfile_chain.c b/src/os/unix/ngx_linux_sendfile_chain.c
--- a/src/os/unix/ngx_linux_sendfile_chain.c
+++ b/src/os/unix/ngx_linux_sendfile_chain.c
@@ -89,10 +89,8 @@ ngx_linux_sendfile_chain(ngx_connection_
 
         /* create the iovec and coalesce the neighbouring bufs */
 
-        for (cl = in;
-             cl && header.nelts < IOV_MAX && send < limit;
-             cl = cl->next)
-        {
+        for (cl = in; cl && send < limit; cl = cl->next) {
+
             if (ngx_buf_special(cl->buf)) {
                 continue;
             }
@@ -132,6 +130,10 @@ ngx_linux_sendfile_chain(ngx_connection_
                 iov->iov_len += (size_t) size;
 
             } else {
+                if (header.nelts >= IOV_MAX) {
+                    break;
+                }
+
                 iov = ngx_array_push(&header);
                 if (iov == NULL) {
                     return NGX_CHAIN_ERROR;
diff --git a/src/os/unix/ngx_solaris_sendfilev_chain.c b/src/os/unix/ngx_solaris_sendfilev_chain.c
--- a/src/os/unix/ngx_solaris_sendfilev_chain.c
+++ b/src/os/unix/ngx_solaris_sendfilev_chain.c
@@ -94,8 +94,8 @@ ngx_solaris_sendfilev_chain(ngx_connecti
 
         /* create the sendfilevec and coalesce the neighbouring bufs */
 
-        for (cl = in; cl && vec.nelts < IOV_MAX && send < limit; cl = cl->next)
-        {
+        for (cl = in; cl && send < limit; cl = cl->next) {
+
             if (ngx_buf_special(cl->buf)) {
                 continue;
             }
@@ -113,6 +113,10 @@ ngx_solaris_sendfilev_chain(ngx_connecti
                     sfv->sfv_len += (size_t) size;
 
                 } else {
+                    if (vec.nelts >= IOV_MAX) {
+                        break;
+                    }
+
                     sfv = ngx_array_push(&vec);
                     if (sfv == NULL) {
                         return NGX_CHAIN_ERROR;
@@ -147,6 +151,10 @@ ngx_solaris_sendfilev_chain(ngx_connecti
                     sfv->sfv_len += (size_t) size;
 
                 } else {
+                    if (vec.nelts >= IOV_MAX) {
+                        break;
+                    }
+
                     sfv = ngx_array_push(&vec);
                     if (sfv == NULL) {
                         return NGX_CHAIN_ERROR;
diff --git a/src/os/unix/ngx_writev_chain.c b/src/os/unix/ngx_writev_chain.c
--- a/src/os/unix/ngx_writev_chain.c
+++ b/src/os/unix/ngx_writev_chain.c
@@ -71,8 +71,8 @@ ngx_writev_chain(ngx_connection_t *c, ng
 
         /* create the iovec and coalesce the neighbouring bufs */
 
-        for (cl = in; cl && vec.nelts < IOV_MAX && send < limit; cl = cl->next)
-        {
+        for (cl = in; cl && send < limit; cl = cl->next) {
+
             if (ngx_buf_special(cl->buf)) {
                 continue;
             }
@@ -93,6 +93,10 @@ ngx_writev_chain(ngx_connection_t *c, ng
                 iov->iov_len += size;
 
             } else {
+                if (vec.nelts >= IOV_MAX) {
+                    break;
+                }
+
                 iov = ngx_array_push(&vec);
                 if (iov == NULL) {
                     return NGX_CHAIN_ERROR;