Initial implementation of an async DNS client API with getaddrinfo + pthreads.

This commit is contained in:
Jan Vidar Krey 2012-10-24 23:19:14 +02:00
parent 19559f4974
commit 793790d089
7 changed files with 521 additions and 8 deletions

View File

@ -83,10 +83,6 @@ if (SQLITE_SUPPORT)
target_link_libraries(mod_auth_sqlite sqlite3 utils)
target_link_libraries(uhub-passwd sqlite3 utils)
set_target_properties(mod_auth_sqlite PROPERTIES PREFIX "")
if (UNIX)
target_link_libraries(uhub pthread)
endif()
endif()
@ -121,11 +117,12 @@ target_link_libraries(mod_logging network)
if(UNIX)
add_library(adcclient STATIC ${adcclient_SOURCES})
add_executable(uhub-admin ${PROJECT_SOURCE_DIR}/tools/admin.c)
target_link_libraries(uhub-admin adcclient adc network utils)
target_link_libraries(uhub-admin adcclient adc network utils pthread)
target_link_libraries(uhub pthread)
if (ADC_STRESS)
add_executable(adcrush ${PROJECT_SOURCE_DIR}/tools/adcrush.c ${adcclient_SOURCES})
target_link_libraries(adcrush adcclient adc network utils)
target_link_libraries(adcrush adcclient adc network utils pthread)
endif()
endif()

View File

@ -146,6 +146,9 @@ int net_backend_process()
return 0;
}
// Process pending DNS results
net_dns_process();
g_backend->handler.backend_process(g_backend->data, res);
net_cleanup_process(g_backend->cleaner);

383
src/network/dnsresolver.c Normal file
View File

@ -0,0 +1,383 @@
/*
* uhub - A tiny ADC p2p connection hub
* Copyright (C) 2007-2012, Jan Vidar Krey
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "uhub.h"
#define DEBUG_LOOKUP_TIME 1
#define MAX_CONCURRENT_JOBS 25
static struct net_dns_job* find_and_remove_job(struct net_dns_job* job);
static struct net_dns_result* find_and_remove_result(struct net_dns_job* job);
struct net_dns_job
{
net_dns_job_cb callback;
void* ptr;
char* host;
int af;
#ifdef DEBUG_LOOKUP_TIME
struct timeval time_start;
struct timeval time_finish;
#endif
#ifdef POSIX_THREAD_SUPPORT
pthread_t thread_handle;
#endif
};
struct net_dns_result
{
struct linked_list* addr_list;
struct net_dns_job* job;
};
static void free_job(struct net_dns_job* job)
{
if (job)
{
hub_free(job->host);
hub_free(job);
}
}
// NOTE: Any job manipulating the members of this
// struct must lock the mutex!
struct net_dns_subsystem
{
struct linked_list* jobs; // currently running jobs
struct linked_list* results; // queue of results that are awaiting being delivered to callback.
#ifdef POSIX_THREAD_SUPPORT
pthread_mutex_t mutex;
#endif // POSIX_THREAD_SUPPORT
};
static struct net_dns_subsystem* g_dns = NULL;
void net_dns_initialize()
{
LOG_TRACE("net_dns_initialize()");
g_dns = (struct net_dns_subsystem*) hub_malloc_zero(sizeof(struct net_dns_subsystem));
g_dns->jobs = list_create();
g_dns->results = list_create();
#ifdef POSIX_THREAD_SUPPORT
pthread_mutex_init(&g_dns->mutex, NULL);
#endif
}
void net_dns_destroy()
{
#ifdef POSIX_THREAD_SUPPORT
struct net_dns_job* job;
pthread_mutex_lock(&g_dns->mutex);
LOG_TRACE("net_dns_destroy(): jobs=%d", (int) list_size(g_dns->jobs));
job = (struct net_dns_job*) list_get_first(g_dns->jobs);
pthread_mutex_unlock(&g_dns->mutex);
while (job)
{
net_dns_job_cancel(job);
pthread_mutex_lock(&g_dns->mutex);
job = (struct net_dns_job*) list_get_first(g_dns->jobs);
pthread_mutex_unlock(&g_dns->mutex);
}
#endif
}
#ifdef POSIX_THREAD_SUPPORT
static void dummy_free(void* ptr)
{
}
#endif
void net_dns_process()
{
#ifdef POSIX_THREAD_SUPPORT
struct net_dns_result* result;
pthread_mutex_lock(&g_dns->mutex);
LOG_DUMP("net_dns_process(): jobs=%d, results=%d", (int) list_size(g_dns->jobs), (int) list_size(g_dns->results));
for (result = (struct net_dns_result*) list_get_first(g_dns->results); result; result = (struct net_dns_result*) list_get_next(g_dns->results))
{
struct net_dns_job* job = result->job;
#ifdef DEBUG_LOOKUP_TIME
struct timeval time_result;
timersub(&result->job->time_finish, &result->job->time_start, &time_result);
LOG_TRACE("DNS lookup took %d ms", (time_result.tv_sec * 1000) + (time_result.tv_usec / 1000));
#endif
// wait for the work thread to finish
pthread_join(job->thread_handle, NULL);
// callback - should we delete the data immediately?
if (job->callback(job, result))
{
net_dns_result_free(result);
}
else
{
/* Caller wants to keep the result data, and
* thus needs to call net_dns_result_free() to release it later.
* We only clean up the job data here and keep the results intact.
*/
result->job = NULL;
free_job(job);
}
}
list_clear(g_dns->results, &dummy_free);
pthread_mutex_unlock(&g_dns->mutex);
#endif // POSIX_THREAD_SUPPORT
}
#ifdef POSIX_THREAD_SUPPORT
static void* job_thread_resolve_name(void* ptr)
{
struct net_dns_job* job = (struct net_dns_job*) ptr;
struct addrinfo hints, *result, *it;
struct net_dns_result* dns_results;
int ret;
memset(&hints, 0, sizeof(hints));
hints.ai_family = job->af;
hints.ai_protocol = IPPROTO_TCP;
ret = getaddrinfo(job->host, NULL, &hints, &result);
if (ret != 0)
{
LOG_WARN("getaddrinfo() failed: %s", gai_strerror(ret));
return NULL;
}
dns_results = (struct net_dns_result*) hub_malloc(sizeof(struct net_dns_result));
dns_results->addr_list = list_create();
dns_results->job = job;
for (it = result; it; it = it->ai_next)
{
struct ip_addr_encap* ipaddr = hub_malloc_zero(sizeof(struct ip_addr_encap));
ipaddr->af = it->ai_family;
if (it->ai_family == AF_INET)
{
struct sockaddr_in* addr4 = (struct sockaddr_in*) it->ai_addr;
memcpy(&ipaddr->internal_ip_data.in, &addr4->sin_addr, sizeof(struct in_addr));
}
else if (it->ai_family == AF_INET6)
{
struct sockaddr_in6* addr6 = (struct sockaddr_in6*) it->ai_addr;
memcpy(&ipaddr->internal_ip_data.in6, &addr6->sin6_addr, sizeof(struct in6_addr));
}
else
{
LOG_WARN("getaddrinfo() returned result with unknown address family: %d", it->ai_family);
hub_free(ipaddr);
continue;
}
LOG_WARN("getaddrinfo() - Address (%d): %s", ret++, ip_convert_to_string(ipaddr));
list_append(dns_results->addr_list, ipaddr);
}
freeaddrinfo(result);
#ifdef DEBUG_LOOKUP_TIME
gettimeofday(&job->time_finish, NULL);
#endif
pthread_mutex_lock(&g_dns->mutex);
list_remove(g_dns->jobs, job);
list_append(g_dns->results, dns_results);
pthread_mutex_unlock(&g_dns->mutex);
return dns_results;
}
#endif
extern struct net_dns_job* net_dns_gethostbyname(const char* host, int af, net_dns_job_cb callback, void* ptr)
{
struct net_dns_job* job = (struct net_dns_job*) hub_malloc_zero(sizeof(struct net_dns_job));
job->host = strdup(host);
job->af = af;
job->callback = callback;
job->ptr = ptr;
#ifdef DEBUG_LOOKUP_TIME
gettimeofday(&job->time_start, NULL);
#endif
// FIXME - scheduling - what about a max number of threads?
#ifdef POSIX_THREAD_SUPPORT
pthread_mutex_lock(&g_dns->mutex);
int err = pthread_create(&job->thread_handle, NULL, job_thread_resolve_name, job);
if (err)
{
LOG_WARN("Unable to create thread: (%d) %s", err, strerror(err));
free_job(job);
job = NULL;
}
else
{
list_append(g_dns->jobs, job);
}
pthread_mutex_unlock(&g_dns->mutex);
#endif
return job;
}
extern struct net_dns_job* net_dns_gethostbyaddr(struct ip_addr_encap* ipaddr, net_dns_job_cb callback, void* ptr)
{
struct net_dns_job* job = (struct net_dns_job*) hub_malloc_zero(sizeof(struct net_dns_job));
// job->host = strdup(addr);
job->af = ipaddr->af;
job->callback = callback;
job->ptr = ptr;
#ifdef POSIX_THREAD_SUPPORT
// if (pthread_create(&job->thread_handle, NULL, start_job, job))
// {
// free_job(job);
// return NULL;
// }
#endif
return job;
}
// NOTE: mutex must be locked first!
static struct net_dns_job* find_and_remove_job(struct net_dns_job* job)
{
struct net_dns_job* it;
for (it = (struct net_dns_job*) list_get_first(g_dns->jobs); it; it = (struct net_dns_job*) list_get_next(g_dns->jobs))
{
if (it == job)
{
list_remove(g_dns->jobs, it);
return job;
}
}
return NULL;
}
// NOTE: mutex must be locked first!
static struct net_dns_result* find_and_remove_result(struct net_dns_job* job)
{
struct net_dns_result* it;
for (it = (struct net_dns_result*) list_get_first(g_dns->results); it; it = (struct net_dns_result*) list_get_next(g_dns->results))
{
if (it->job == job)
{
list_remove(g_dns->results, it);
return it;
}
}
return NULL;
}
extern int net_dns_job_cancel(struct net_dns_job* job)
{
#ifdef POSIX_THREAD_SUPPORT
int retval = 0;
struct net_dns_result* res;
LOG_TRACE("net_dns_job_cancel(): job=%p, name=%s", job, job->host);
/*
* This function looks up the job in the jobs queue (which contains only active jobs)
* If that is found then the thread is cancelled, and the object is deleted.
* If the job was not found, that is either because it was an invalid job, or because
* it was already finished. At which point it was not deleted.
* If the job is already finished, but the result has not been delivered, then this
* deletes the result and the job.
*/
pthread_mutex_lock(&g_dns->mutex);
if (find_and_remove_job(job))
{
// job still active - cancel it, then close it.
pthread_cancel(job->thread_handle);
pthread_join(job->thread_handle, NULL);
free_job(job);
retval = 1;
}
else if ((res = find_and_remove_result(job)))
{
// job already finished - close it.
pthread_join(job->thread_handle, NULL);
net_dns_result_free(res);
}
pthread_mutex_unlock(&g_dns->mutex);
return retval;
#endif
}
extern struct net_dns_result* net_dns_job_sync_wait(struct net_dns_job* job)
{
struct net_dns_result* res = NULL;
// Wait for job to finish (if not already)
// This should make sure the job is removed from jobs and a result is
// present in results.
pthread_join(job->thread_handle, NULL);
// Remove the result in order to prevent the callback from being called.
pthread_mutex_lock(&g_dns->mutex);
res = find_and_remove_result(job);
uhub_assert(res != NULL);
res->job = NULL;
free_job(job);
pthread_mutex_unlock(&g_dns->mutex);
return res;
}
void* net_dns_job_get_ptr(const struct net_dns_job* job)
{
return job->ptr;
}
extern size_t net_dns_result_size(const struct net_dns_result* res)
{
return list_size(res->addr_list);
}
extern struct ip_addr_encap* net_dns_result_first(const struct net_dns_result* res)
{
struct ip_addr_encap* ipaddr = list_get_first(res->addr_list);
LOG_TRACE("net_dns_result_first() - Address: %s", ip_convert_to_string(ipaddr));
return ipaddr;
}
extern struct ip_addr_encap* net_dns_result_next(const struct net_dns_result* res)
{
struct ip_addr_encap* ipaddr = list_get_next(res->addr_list);
LOG_TRACE("net_dns_result_next() - Address: %s", ip_convert_to_string(ipaddr));
return ipaddr;
}
extern void net_dns_result_free(struct net_dns_result* res)
{
list_clear(res->addr_list, &hub_free);
list_destroy(res->addr_list);
free_job(res->job);
hub_free(res);
}

119
src/network/dnsresolver.h Normal file
View File

@ -0,0 +1,119 @@
/*
* uhub - A tiny ADC p2p connection hub
* Copyright (C) 2007-2012, Jan Vidar Krey
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef HAVE_UHUB_NETWORK_DNS_RESOLVER_H
#define HAVE_UHUB_NETWORK_DNS_RESOLVER_H
struct net_dns_job;
struct net_dns_result;
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
/// Initialize the DNS subsystem
void net_dns_initialize();
/// Shutdown and destroy the DNS subsystem. This will cancel any pending DNS jobs.
void net_dns_destroy();
/// Process finished DNS lookups.
void net_dns_process();
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
/**
* Callback to be called when the DNS job has finished.
* If the name or address could not be resolved to an IP address (host not found, or found but has no address)
* then 'result' contains an empty list (@see net_dns_result_size()).
* If resolving caused an error then result is NULL.
*
* After this callback is called the job is considered done, and is freed.
*
* @param If 1 is returned then result is deleted immediately after the callback,
* otherwise the callback becomes owner of the result data which must be freed with net_dns_result_free().
*/
typedef int (*net_dns_job_cb)(struct net_dns_job*, const struct net_dns_result* result);
/**
* Resolve a hostname.
*
* @param host the hostname to be resolved.
* @param af the indicated address family. Should be AF_INET, AF_INET6 (or AF_UNSPEC - which means both AF_INET and AF_INET6.
* @param callback the callback to be called when the hostname has been resolved.
* @param ptr A user-defined pointer value.
*
* @return A resolve job handle if the job has successfully started or NULL if unable to start resolving.
*/
extern struct net_dns_job* net_dns_gethostbyname(const char* host, int af, net_dns_job_cb callback, void* ptr);
/**
* Perform a reverse DNS lookup for a given IP address.
*
* @see net_dns_gethostbyname()
* @return A resolve job handle if the job has successfully started or NULL if unable to start resolving.
*/
extern struct net_dns_job* net_dns_gethostbyaddr(struct ip_addr_encap* ipaddr, net_dns_job_cb callback, void* ptr);
/**
* Cancel a DNS lookup job.
*
* It is only allowed to call this once after a job has been started (@see net_dns_gethostbyname(), @see net_dns_gethostbyaddr())
* but before it has finished and delivered a to the callback address (@see net_dns_job_cb).
*
* @returns 1 if cancelled, or 0 if not cancelled (because the job was not found!)
*/
extern int net_dns_job_cancel(struct net_dns_job* job);
/**
* Wait in a synchronous manner for a running DNS job to finished and
* return the result here.
* The job must be started with net_dns_gethostbyaddr/net_dns_gethostbyname
* and not finished or cancelled.
*
* If this function is invoked then the callback function will not be called and
* can therefore be NULL.
*
* <code>
* struct net_dns_job* job = net_dns_gethostbyname("www.example.com", AF_INET, NULL, NULL);
* struct net_dns_result* net_dns_job_sync_wait(job);
* </code>
*/
extern struct net_dns_result* net_dns_job_sync_wait(struct net_dns_job* job);
/**
* Returns the user specified pointer assigned to the resolving job
*/
extern void* net_dns_job_get_ptr(const struct net_dns_job* job);
/// Returns the number of results provided. This is 0 if the host could not be found (or has no matching IP address).
extern size_t net_dns_result_size(const struct net_dns_result*);
/// Returns the first result (if net_dns_result_size > 0), or NULL if not first result exists.
extern struct ip_addr_encap* net_dns_result_first(const struct net_dns_result*);
/// Returns the next result or NULL if no next result exists.
extern struct ip_addr_encap* net_dns_result_next(const struct net_dns_result*);
/// When finished with the results
extern void net_dns_result_free(struct net_dns_result*);
#endif /* HAVE_UHUB_NETWORK_DNS_RESOLVER_H */

View File

@ -60,6 +60,9 @@ int net_initialize()
#endif
return -1;
}
net_dns_initialize();
net_stats_initialize();
net_initialized = 1;
return 0;
@ -94,8 +97,10 @@ int net_destroy()
{
LOG_TRACE("Shutting down network monitor");
net_dns_destroy();
net_backend_shutdown();
#ifdef SSL_SUPPORT
net_ssl_library_shutdown();
#endif /* SSL_SUPPORT */
@ -490,7 +495,6 @@ int net_socket_create(int af, int type, int protocol)
}
}
#endif
return sd;
}

View File

@ -113,11 +113,13 @@
#define uhub_assert assert
#ifdef __linux__
#define POSIX_THREAD_SUPPORT
#define USE_EPOLL
#include <sys/epoll.h>
#endif
#ifdef BSD_LIKE
#define POSIX_THREAD_SUPPORT
/*
#define USE_KQUEUE
#include <sys/event.h>
@ -279,6 +281,10 @@ typedef unsigned __int64 uint64_t;
#define NEED_GETOPT
#endif
#ifdef POSIX_THREAD_SUPPORT
#include <pthread.h>
#endif
#if defined(__CYGWIN__) || defined(__MINGW32__) || defined(_MSC_VER)
#define PLUGIN_API __declspec(dllexport)
#else

View File

@ -74,6 +74,7 @@ extern "C" {
#include "network/network.h"
#include "network/connection.h"
#include "network/dnsresolver.h"
#include "network/ipcalc.h"
#include "network/timeout.h"