curl/lib
Tobias Stoeckmann 851c29269b hostip: Fix signal race in Curl_resolv_timeout.
A signal handler for SIGALRM is installed in Curl_resolv_timeout. It is
configured to interrupt system calls and uses siglongjmp to return into
the function if alarm() goes off.

The signal handler is installed before curl_jmpenv is initialized.
This means that an already installed alarm timer could trigger the
newly installed signal handler, leading to undefined behavior when it
accesses the uninitialized curl_jmpenv.

Even if there is no previously installed alarm available, the code in
Curl_resolv_timeout itself installs an alarm before the environment is
fully set up. If the process is sent into suspend right after that, the
signal handler could be called too early as in previous scenario.

To fix this, the signal handler should only be installed and the alarm
timer only be set after sigsetjmp has been called.
2015-03-14 18:24:11 +01:00
..
vtls openssl: use colons properly in the ciphers list 2015-03-12 23:29:46 +01:00
.gitignore
amigaos.c
amigaos.h
arpa_telnet.h
asyn-ares.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
asyn-thread.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
asyn.h
base64.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
bundles.c
bundles.h
checksrc.pl
CMakeLists.txt cmake: install the dll file to the correct directory 2015-02-20 14:17:32 +01:00
config-amigaos.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-dos.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-mac.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-os400.h
config-riscos.h
config-symbian.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-tpf.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-vxworks.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-win32.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
config-win32ce.h
conncache.c proxy: re-use proxy connections (regression) 2015-03-11 11:54:22 +01:00
conncache.h proxy: re-use proxy connections (regression) 2015-03-11 11:54:22 +01:00
connect.c conncontrol: only log changes to the connection bit 2015-03-07 19:18:49 +01:00
connect.h
content_encoding.c
content_encoding.h
cookie.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
cookie.h
curl_addrinfo.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_addrinfo.h
curl_base64.h
curl_config.h.cmake openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_des.c openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_des.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_endian.c
curl_endian.h
curl_fnmatch.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_fnmatch.h
curl_gethostname.c
curl_gethostname.h
curl_gssapi.c
curl_gssapi.h
curl_hmac.h
curl_ldap.h
curl_md4.h
curl_md5.h
curl_memory.h
curl_memrchr.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_memrchr.h
curl_multibyte.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_multibyte.h
curl_ntlm.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_ntlm.h
curl_ntlm_core.c openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_ntlm_core.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_ntlm_msgs.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_ntlm_msgs.h
curl_ntlm_wb.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_ntlm_wb.h
curl_printf.h vtls: use curl_printf.h all over 2015-03-03 23:17:43 +01:00
curl_rtmp.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_rtmp.h
curl_sasl.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_sasl.h
curl_sasl_gssapi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_sasl_sspi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_sec.h
curl_setup.h openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
curl_setup_once.h
curl_sspi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_sspi.h
curl_threads.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
curl_threads.h
curlx.h vtls: use curl_printf.h all over 2015-03-03 23:17:43 +01:00
dict.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
dict.h
dotdot.c
dotdot.h
easy.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
easyif.h
escape.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
escape.h
file.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
file.h
fileinfo.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
fileinfo.h
firefox-db2pem.sh
formdata.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
formdata.h
ftp.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
ftp.h
ftplistparser.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
ftplistparser.h
getenv.c
getinfo.c openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
getinfo.h
gopher.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
gopher.h
hash.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
hash.h
hmac.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
hostasyn.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
hostcheck.c openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
hostcheck.h
hostip.c hostip: Fix signal race in Curl_resolv_timeout. 2015-03-14 18:24:11 +01:00
hostip.h
hostip4.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
hostip6.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
hostsyn.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
http.c http: always send Host: header as first header 2015-03-12 12:15:24 +01:00
http.h http2: Return error if stream was closed with other than NO_ERROR 2015-02-27 21:17:27 +00:00
http2.c http2: detect prematures close without data transfered 2015-03-14 18:19:51 +01:00
http2.h
http_chunks.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
http_chunks.h
http_digest.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
http_digest.h
http_negotiate.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
http_negotiate.h
http_negotiate_sspi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
http_proxy.c multi: fix *getsock() with CONNECT 2015-03-07 19:19:22 +01:00
http_proxy.h
idn_win32.c
if2ip.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
if2ip.h
imap.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
imap.h
inet_ntop.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
inet_ntop.h
inet_pton.c
inet_pton.h
krb5.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
ldap.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
libcurl.def
libcurl.plist
libcurl.rc
libcurl.vers.in
llist.c
llist.h
Makefile.am
makefile.amiga
Makefile.b32 openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
makefile.dj
Makefile.inc mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
Makefile.m32 openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
Makefile.netware
Makefile.vc6 openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
Makefile.vxworks
Makefile.Watcom
md4.c MD(4|5): make the MD4_* and MD5_* functions static 2015-02-06 14:26:32 +01:00
md5.c openssl: remove all uses of USE_SSLEAY 2015-03-05 10:57:52 +01:00
memdebug.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
memdebug.h
mk-ca-bundle.pl mk-ca-bundle bugfix: Don't report SHA1 numbers with "-q". 2015-03-11 14:47:41 +01:00
mk-ca-bundle.vbs
mprintf.c
multi.c multi: fix *getsock() with CONNECT 2015-03-07 19:19:22 +01:00
multihandle.h multi: fix *getsock() with CONNECT 2015-03-07 19:19:22 +01:00
multiif.h
netrc.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
netrc.h
non-ascii.c
non-ascii.h
nonblock.c
nonblock.h
nwlib.c
nwos.c
objnames-test08.sh
objnames-test10.sh
objnames.inc
openldap.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
parsedate.c
parsedate.h
pingpong.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
pingpong.h
pipeline.c
pipeline.h
pop3.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
pop3.h
progress.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
progress.h
rawstr.c
rawstr.h
README.ares
README.curl_off_t
README.curlx
README.encoding
README.hostip
README.http2
README.httpauth
README.memoryleak
README.multi_socket
README.pingpong
README.pipelining
rtsp.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
rtsp.h
security.c security: avoid compiler warning 2015-01-28 10:10:59 +01:00
select.c
select.h
sendf.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
sendf.h
setup-os400.h
setup-vms.h
share.c
share.h
sigpipe.h
slist.c
slist.h
smb.c
smb.h
smtp.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
smtp.h
sockaddr.h
socks.c
socks.h
socks_gssapi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
socks_sspi.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
speedcheck.c
speedcheck.h
splay.c
splay.h
ssh.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
ssh.h
strdup.c
strdup.h
strequal.c
strequal.h
strerror.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
strerror.h
strtok.c
strtok.h
strtoofft.c
strtoofft.h
telnet.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
telnet.h
tftp.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
tftp.h
timeval.c
timeval.h
transfer.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
transfer.h
url.c proxy: re-use proxy connections (regression) 2015-03-11 11:54:22 +01:00
url.h
urldata.h http2: use CURL_HTTP_VERSION_* symbols instead of NPN_* 2015-03-07 11:10:30 +01:00
version.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
warnless.c
warnless.h
wildcard.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
wildcard.h
x509asn1.c mprintf.h: remove #ifdef CURLDEBUG 2015-03-03 12:36:18 +01:00
x509asn1.h

HTTP Pipelining with libcurl
============================

Background

Since pipelining implies that one or more requests are sent to a server before
the previous response(s) have been received, we only support it for multi
interface use.

Considerations

When using the multi interface, you create one easy handle for each transfer.
Bascially any number of handles can be created, added and used with the multi
interface - simultaneously. It is an interface designed to allow many
simultaneous transfers while still using a single thread. Pipelining does not
change any of these details.

API

We've added a new option to curl_multi_setopt() called CURLMOPT_PIPELINING
that enables "attempted pipelining" and then all easy handles used on that
handle will attempt to use an existing pipeline.

Details

- A pipeline is only created if a previous connection exists to the same IP
  address that the new request is being made to use.

- Pipelines are only supported for HTTP(S) as no other currently supported
  protocol has features resemembling this, but we still name this feature
  plain 'pipelining' to possibly one day support it for other protocols as
  well.

- HTTP Pipelining is for GET and HEAD requests only.

- When a pipeline is in use, we must take precautions so that when used easy
  handles (i.e those who still wait for a response) are removed from the multi
  handle, we must deal with the outstanding response nicely.

- Explicitly asking for pipelining handle X and handle Y won't be supported.
  It isn't easy for an app to do this association. The lib should probably
  still resolve the second one properly to make sure that they actually _can_
  be considered for pipelining. Also, asking for explicit pipelining on handle
  X may be tricky when handle X get a closed connection.