SIGPIPE: ignored while inside the library

... and restore the ordinary handling again when it returns. This is
done for curl_easy_perform() and curl_easy_cleanup() only for now - and
only when built to use OpenSSL as backend as this is the known culprit
for the spurious SIGPIPEs people have received.

Bug: http://curl.haxx.se/bug/view.cgi?id=1180
Reported by: Lluís Batlle i Rossell
This commit is contained in:
Daniel Stenberg 2013-03-11 00:39:52 +01:00
parent a2e0ce86ba
commit 7d80ed64e4
1 changed files with 56 additions and 0 deletions

View File

@ -50,6 +50,11 @@
#include <sys/param.h>
#endif
#if defined(HAVE_SIGNAL_H) && defined(HAVE_SIGACTION) && defined(USE_OPENSSL)
#define SIGPIPE_IGNORE 1
#include <signal.h>
#endif
#include "strequal.h"
#include "urldata.h"
#include <curl/curl.h>
@ -81,6 +86,49 @@
/* The last #include file should be: */
#include "memdebug.h"
#ifdef SIGPIPE_IGNORE
#define SIGPIPE_VARIABLE(x) struct sigaction x
/*
* sigpipe_ignore() makes sure we ignore SIGPIPE while running libcurl
* internals, and then sigpipe_restore() will restore the situation when we
* return from libcurl again.
*/
static void sigpipe_ignore(struct SessionHandle *data,
struct sigaction *pipe)
{
if(!data->set.no_signal) {
struct sigaction action;
/* first, extract the existing situation */
sigaction(SIGPIPE, NULL, pipe);
action = *pipe;
/* ignore this signal */
action.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &action, NULL);
}
}
/*
* sigpipe_restore() puts back the outside world's opinion of signal handler
* and SIGPIPE handling. It MUST only be called after a corresponding
* sigpipe_ignore() was used.
*/
static void sigpipe_restore(struct SessionHandle *data,
struct sigaction *pipe)
{
if(!data->set.no_signal) {
/* restore the outside state */
sigaction(SIGPIPE, pipe, NULL);
}
}
#else
/* for systems without sigaction */
#define sigpipe_ignore(x,y)
#define sigpipe_restore(x,y)
#define SIGPIPE_VARIABLE(x)
#endif
/* win32_cleanup() is for win32 socket cleanup functionality, the opposite
of win32_init() */
static void win32_cleanup(void)
@ -423,6 +471,7 @@ CURLcode curl_easy_perform(CURL *easy)
int without_fds = 0; /* count number of consecutive returns from
curl_multi_wait() without any filedescriptors */
struct timeval before;
SIGPIPE_VARIABLE(pipe);
if(!easy)
return CURLE_BAD_FUNCTION_ARGUMENT;
@ -455,6 +504,8 @@ CURLcode curl_easy_perform(CURL *easy)
return CURLE_FAILED_INIT;
}
sigpipe_ignore(data, &pipe);
/* assign this after curl_multi_add_handle() since that function checks for
it and rejects this handle otherwise */
data->multi = multi;
@ -511,6 +562,8 @@ CURLcode curl_easy_perform(CURL *easy)
a failure here, room for future improvement! */
(void)curl_multi_remove_handle(multi, easy);
sigpipe_restore(data, &pipe);
/* The multi handle is kept alive, owned by the easy handle */
return code;
}
@ -522,11 +575,14 @@ CURLcode curl_easy_perform(CURL *easy)
void curl_easy_cleanup(CURL *curl)
{
struct SessionHandle *data = (struct SessionHandle *)curl;
SIGPIPE_VARIABLE(pipe);
if(!data)
return;
sigpipe_ignore(data, &pipe);
Curl_close(data);
sigpipe_restore(data, &pipe);
}
/*