【发布时间】：2011-03-17 22:03:30
【问题描述】：
所以我有一堆工作线程做简单的 curl 类，每个工作线程都有自己的 curl 简单句柄。他们只在随机网站上进行 HEAD 查找。还存在锁定功能以启用多线程 SSL，如文档 here 所述。除了 2 个网页 ilsole24ore.com（见下例）和 Ninemsn.com.au/ 外，一切正常，它们有时会产生 seg 错误，如此处所示的跟踪输出所示
#0 *__GI___libc_res_nquery (statp=0xb4d12df4, name=0x849e9bd "ilsole24ore.com", class=1, type=1, answer=0xb4d0ca10 "", anslen=1024, answerp=0xb4d0d234,
answerp2=0x0, nanswerp2=0x0, resplen2=0x0) at res_query.c:182
#1 0x00434e8b in __libc_res_nquerydomain (statp=0xb4d12df4, name=0xb4d0ca10 "", domain=0x0, class=1, type=1, answer=0xb4d0ca10 "", anslen=1024,
answerp=0xb4d0d234, answerp2=0x0, nanswerp2=0x0, resplen2=0x0) at res_query.c:576
#2 0x004352b5 in *__GI___libc_res_nsearch (statp=0xb4d12df4, name=0x849e9bd "ilsole24ore.com", class=1, type=1, answer=0xb4d0ca10 "", anslen=1024,
answerp=0xb4d0d234, answerp2=0x0, nanswerp2=0x0, resplen2=0x0) at res_query.c:377
#3 0x009c0bd6 in *__GI__nss_dns_gethostbyname3_r (name=0x849e9bd "ilsole24ore.com", af=2, result=0xb4d0d5fc, buffer=0xb4d0d300 "\177", buflen=512,
errnop=0xb4d12b30, h_errnop=0xb4d0d614, ttlp=0x0, canonp=0x0) at nss_dns/dns-host.c:197
#4 0x009c0f2b in _nss_dns_gethostbyname2_r (name=0x849e9bd "ilsole24ore.com", af=2, result=0xb4d0d5fc, buffer=0xb4d0d300 "\177", buflen=512,
errnop=0xb4d12b30, h_errnop=0xb4d0d614) at nss_dns/dns-host.c:251
#5 0x0079eacd in __gethostbyname2_r (name=0x849e9bd "ilsole24ore.com", af=2, resbuf=0xb4d0d5fc, buffer=0xb4d0d300 "\177", buflen=512, result=0xb4d0d618,
h_errnop=0xb4d0d614) at ../nss/getXXbyYY_r.c:253
#6 0x00760010 in gaih_inet (name=<value optimized out>, service=<value optimized out>, req=0xb4d0f83c, pai=0xb4d0d764, naddrs=0xb4d0d754)
at ../sysdeps/posix/getaddrinfo.c:531
#7 0x00761a65 in *__GI_getaddrinfo (name=0x849e9bd "ilsole24ore.com", service=0x0, hints=0xb4d0f83c, pai=0xb4d0f860) at ../sysdeps/posix/getaddrinfo.c:2160
#8 0x00917f9a in ?? () from /usr/lib/libkrb5support.so.0
#9 0x003b2f45 in krb5_sname_to_principal () from /usr/lib/libkrb5.so.3
#10 0x0028a278 in ?? () from /usr/lib/libgssapi_krb5.so.2
#11 0x0027eff2 in ?? () from /usr/lib/libgssapi_krb5.so.2
#12 0x0027fb00 in gss_init_sec_context () from /usr/lib/libgssapi_krb5.so.2
#13 0x00d8770e in ?? () from /usr/lib/libcurl.so.4
#14 0x00d62c27 in ?? () from /usr/lib/libcurl.so.4
#15 0x00d7e25b in ?? () from /usr/lib/libcurl.so.4
#16 0x00d7e597 in ?? () from /usr/lib/libcurl.so.4
#17 0x00d7f133 in curl_easy_perform () from /usr/lib/libcurl.so.4
我的函数看起来像这样
int do_http_check(taskinfo *info,standardResult *data)
{
standardResultInit(data);
char errorBuffer[CURL_ERROR_SIZE];
CURL *curl;
CURLcode result;
curl = curl_easy_init();
if(curl)
{
//required options first
curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errorBuffer);
curl_easy_setopt(curl, CURLOPT_URL, info->address.c_str());
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writer);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &data->body);
curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, writer);
curl_easy_setopt(curl, CURLOPT_WRITEHEADER, &data->head);
curl_easy_setopt(curl, CURLOPT_DNS_USE_GLOBAL_CACHE,0);
curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 30 );
curl_easy_setopt(curl, CURLOPT_NOSIGNAL,1);
curl_easy_setopt(curl, CURLOPT_NOBODY,1);
curl_easy_setopt(curl, CURLOPT_TIMEOUT ,240);
//optional options
if(info->options.follow)
{
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(curl, CURLOPT_MAXREDIRS, info->options.redirects);
}
result = curl_easy_perform(curl);
if (result == CURLE_OK)
{
data->success = true;
curl_easy_getinfo(curl,CURLINFO_RESPONSE_CODE,&data->httpMsg);
curl_easy_getinfo(curl,CURLINFO_REDIRECT_COUNT,&data->numRedirects);
data->msg = "OK";
}
else
{
... handle error
}
return 1;
}
现在，当我在没有任何线程的情况下调用函数时，只是从 main 调用它永远不会中断，所以我在想它连接到线程，或者可能是如何返回数据返回结构，但从我在跟踪中看到的看起来就像在 easy_perform() 调用中产生的错误一样，这让我很困惑。 因此，如果有人知道我接下来应该在哪里看，那将是最有帮助的，谢谢。
【问题讨论】：
标签： c curl segmentation-fault pthreads