From 070718b3e00d0341d44dd5ad4b48fd4468d047c6 Mon Sep 17 00:00:00 2001

From: Daniel Stenberg <daniel@haxx.se>

Date: Sat, 9 Mar 2013 22:26:07 +0100

Subject: [PATCH 1/3] curl_multi_wait: avoid second loop if nothing to do

... hopefully this will also make clang-analyzer stop warning on

potentional NULL dereferences (which were false positives anyway).

Upstream-commit: 136a3a0ee25f28fec1dde216467389f9e6e4f65c

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 lib/multi.c | 55 ++++++++++++++++++++++++++++++++-----------------------

 1 file changed, 32 insertions(+), 23 deletions(-)

diff --git a/lib/multi.c b/lib/multi.c

index 6dfce9b..1136849 100644

--- a/lib/multi.c

+++ b/lib/multi.c

@@ -804,7 +804,8 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

   curl_socket_t sockbunch[MAX_SOCKSPEREASYHANDLE];

   int bitmap;

   unsigned int i;

-  unsigned int nfds = extra_nfds;

+  unsigned int nfds = 0;

+  unsigned int curlfds;

   struct pollfd *ufds = NULL;

   long timeout_internal;

@@ -842,6 +843,9 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

     easy = easy->next; /* check next handle */

   }

+  curlfds = nfds; /* number of internal file descriptors */

+  nfds += extra_nfds; /* add the externally provided ones */

+

   if(nfds) {

     ufds = malloc(nfds * sizeof(struct pollfd));

     if(!ufds)

@@ -849,32 +853,37 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

   }

   nfds = 0;

-  /* Add the curl handles to our pollfds first */

-  easy=multi->easy.next;

-  while(easy != &multi->easy) {

-    bitmap = multi_getsock(easy, sockbunch, MAX_SOCKSPEREASYHANDLE);

+  /* only do the second loop if we found descriptors in the first stage run

+     above */

-    for(i=0; i< MAX_SOCKSPEREASYHANDLE; i++) {

-      curl_socket_t s = CURL_SOCKET_BAD;

+  if(curlfds) {

+    /* Add the curl handles to our pollfds first */

+    easy=multi->easy.next;

+    while(easy != &multi->easy) {

+      bitmap = multi_getsock(easy, sockbunch, MAX_SOCKSPEREASYHANDLE);

-      if(bitmap & GETSOCK_READSOCK(i)) {

-        ufds[nfds].fd = sockbunch[i];

-        ufds[nfds].events = POLLIN;

-        ++nfds;

-        s = sockbunch[i];

-      }

-      if(bitmap & GETSOCK_WRITESOCK(i)) {

-        ufds[nfds].fd = sockbunch[i];

-        ufds[nfds].events = POLLOUT;

-        ++nfds;

-        s = sockbunch[i];

-      }

-      if(s == CURL_SOCKET_BAD) {

-        break;

+      for(i=0; i< MAX_SOCKSPEREASYHANDLE; i++) {

+        curl_socket_t s = CURL_SOCKET_BAD;

+

+        if(bitmap & GETSOCK_READSOCK(i)) {

+          ufds[nfds].fd = sockbunch[i];

+          ufds[nfds].events = POLLIN;

+          ++nfds;

+          s = sockbunch[i];

+        }

+        if(bitmap & GETSOCK_WRITESOCK(i)) {

+          ufds[nfds].fd = sockbunch[i];

+          ufds[nfds].events = POLLOUT;

+          ++nfds;

+          s = sockbunch[i];

+        }

+        if(s == CURL_SOCKET_BAD) {

+          break;

+        }

       }

-    }

-    easy = easy->next; /* check next handle */

+      easy = easy->next; /* check next handle */

+    }

   }

   /* Add external file descriptions from poll-like struct curl_waitfd */

-- 

2.5.5

From f8b84a52088a99d8128c2234f626ed233beabeae Mon Sep 17 00:00:00 2001

From: Evgeny Turnaev <turnaev.e@gmail.com>

Date: Thu, 18 Jul 2013 00:06:09 +0200

Subject: [PATCH 2/3] curl_multi_wait: set revents for extra fds

Pass back the revents that happened for the user-provided file

descriptors.

Upstream-commit: 6d30f8ebed34e7276c2a59ee20d466bff17fee56

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 lib/multi.c | 5 ++++-

 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/multi.c b/lib/multi.c

index 1136849..81bcfba 100644

--- a/lib/multi.c

+++ b/lib/multi.c

@@ -803,7 +803,7 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

   struct Curl_one_easy *easy;

   curl_socket_t sockbunch[MAX_SOCKSPEREASYHANDLE];

   int bitmap;

-  unsigned int i;

+  unsigned int i, j;

   unsigned int nfds = 0;

   unsigned int curlfds;

   struct pollfd *ufds = NULL;

@@ -905,6 +905,9 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

   else

     i = 0;

+  for(j = nfds - extra_nfds; j < nfds; j++)

+    extra_fds[j].revents = ufds[j].revents;

+

   Curl_safefree(ufds);

   if(ret)

     *ret = i;

-- 

2.5.5

From db2e5b5ffe5408aa892dee9e7f036fe0ea16963d Mon Sep 17 00:00:00 2001

From: Daniel Stenberg <daniel@haxx.se>

Date: Thu, 18 Jul 2013 23:36:59 +0200

Subject: [PATCH 3/3] curl_multi_wait: fix revents

Commit 6d30f8ebed34e7276 didn't work properly. First, it used the wrong

array index, but this fix also:

1 - only does the copying if indeed there was any activity

2 - makes sure to properly translate between internal and external

bitfields, which are not guaranteed to match

Reported-by: Evgeny Turnaev

Upstream-commit: 513e587c5eb966038731530c8f47fe0cf27513ce

Signed-off-by: Kamil Dudka <kdudka@redhat.com>

---

 lib/multi.c | 28 +++++++++++++++++++++++-----

 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/lib/multi.c b/lib/multi.c

index 81bcfba..0e0bb19 100644

--- a/lib/multi.c

+++ b/lib/multi.c

@@ -803,7 +803,7 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

   struct Curl_one_easy *easy;

   curl_socket_t sockbunch[MAX_SOCKSPEREASYHANDLE];

   int bitmap;

-  unsigned int i, j;

+  unsigned int i;

   unsigned int nfds = 0;

   unsigned int curlfds;

   struct pollfd *ufds = NULL;

@@ -899,15 +899,33 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,

     ++nfds;

   }

-  if(nfds)

+  if(nfds) {

     /* wait... */

     i = Curl_poll(ufds, nfds, timeout_ms);

+

+    if(i) {

+      unsigned int j;

+      /* copy revents results from the poll to the curl_multi_wait poll

+         struct, the bit values of the actual underlying poll() implementation

+         may not be the same as the ones in the public libcurl API! */

+      for(j = 0; j < extra_nfds; j++) {

+        unsigned short mask = 0;

+        unsigned r = ufds[curlfds + j].revents;

+

+        if(r & POLLIN)

+          mask |= CURL_WAIT_POLLIN;

+        if(r & POLLOUT)

+          mask |= CURL_WAIT_POLLOUT;

+        if(r & POLLPRI)

+          mask |= CURL_WAIT_POLLPRI;

+

+        extra_fds[j].revents = mask;

+      }

+    }

+  }

   else

     i = 0;

-  for(j = nfds - extra_nfds; j < nfds; j++)

-    extra_fds[j].revents = ufds[j].revents;

-

   Curl_safefree(ufds);

   if(ret)

     *ret = i;

-- 

2.5.5