HGKeeper

/**

* @file dnsquery.c DNS query API

* @ingroup core

/* purple

* Purple is the legal property of its developers, whose names are too numerous

* to list here. Please refer to the COPYRIGHT file distributed with this

* source distribution.

* 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 2 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, write to the Free Software

* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA

#define _PURPLE_DNSQUERY_C_

#include "internal.h"

#include "debug.h"

#include "dnsquery.h"

#include "glibcompat.h"

#include "network.h"

#include "notify.h"

#include "prefs.h"

#include "util.h"

#ifndef _WIN32

#include <resolv.h>

#endif

#define MAX_ADDR_RESPONSE_LEN 1048576

#if (defined(__APPLE__) || defined (__unix__)) && !defined(__osf__)

#define PURPLE_DNSQUERY_USE_FORK

#endif

/**************************************************************************

* DNS query API

**************************************************************************/

static PurpleDnsQueryUiOps *dns_query_ui_ops = NULL;

typedef struct _PurpleDnsQueryResolverProcess PurpleDnsQueryResolverProcess;

struct _PurpleDnsQueryData {

char *hostname;

int port;

PurpleDnsQueryConnectFunction callback;

gpointer data;

guint timeout;

PurpleAccount *account;

#if defined(PURPLE_DNSQUERY_USE_FORK)

PurpleDnsQueryResolverProcess *resolver;

#elif defined _WIN32 /* end PURPLE_DNSQUERY_USE_FORK */

GThread *resolver;

GSList *hosts;

gchar *error_message;

#endif

};

#if defined(PURPLE_DNSQUERY_USE_FORK)

#define MAX_DNS_CHILDREN 4

* This structure keeps a reference to a child resolver process.

struct _PurpleDnsQueryResolverProcess {

guint inpa;

int fd_in, fd_out;

pid_t dns_pid;

};

static GSList *free_dns_children = NULL;

/* TODO: Make me a GQueue when we require >= glib 2.4 */

static GSList *queued_requests = NULL;

static int number_of_dns_children = 0;

* This is a convenience struct used to pass data to

* the child resolver process.

typedef struct {

char hostname[512];

int port;

} dns_params_t;

#endif /* end PURPLE_DNSQUERY_USE_FORK */

static void

purple_dnsquery_resolved(PurpleDnsQueryData *query_data, GSList *hosts)

{

purple_debug_info("dnsquery", "IP resolved for %s\n", query_data->hostname);

if (query_data->callback != NULL)

query_data->callback(hosts, query_data->data, NULL);

else

{

* Callback is a required parameter, but it can get set to

* NULL if we cancel a thread-based DNS lookup. So we need

* to free hosts.

while (hosts != NULL)

{

hosts = g_slist_remove(hosts, hosts->data);

g_free(hosts->data);

hosts = g_slist_remove(hosts, hosts->data);

}

#ifdef PURPLE_DNSQUERY_USE_FORK

* Add the resolver to the list of available resolvers, and set it

* to NULL so that it doesn't get destroyed along with the query_data

if (query_data->resolver)

{

free_dns_children = g_slist_prepend(free_dns_children, query_data->resolver);

query_data->resolver = NULL;

}

#endif /* PURPLE_DNSQUERY_USE_FORK */

purple_dnsquery_destroy(query_data);

}

static void

purple_dnsquery_failed(PurpleDnsQueryData *query_data, const gchar *error_message)

{

purple_debug_error("dnsquery", "%s\n", error_message);

if (query_data->callback != NULL)

query_data->callback(NULL, query_data->data, error_message);

purple_dnsquery_destroy(query_data);

}

static gboolean

purple_dnsquery_ui_resolve(PurpleDnsQueryData *query_data)

{

PurpleDnsQueryUiOps *ops = purple_dnsquery_get_ui_ops();

if (ops && ops->resolve_host)

return ops->resolve_host(query_data, purple_dnsquery_resolved, purple_dnsquery_failed);

return FALSE;

}

static gboolean

resolve_ip(PurpleDnsQueryData *query_data)

{

#if defined(HAVE_GETADDRINFO) && defined(AI_NUMERICHOST)

struct addrinfo hints, *res;

char servname[20];

g_snprintf(servname, sizeof(servname), "%d", query_data->port);

memset(&hints, 0, sizeof(hints));

hints.ai_family = AF_UNSPEC;

hints.ai_flags |= AI_NUMERICHOST;

if (0 == getaddrinfo(query_data->hostname, servname, &hints, &res))

{

GSList *hosts = NULL;

hosts = g_slist_append(hosts, GINT_TO_POINTER(res->ai_addrlen));

hosts = g_slist_append(hosts, g_memdup2(res->ai_addr, res->ai_addrlen));

purple_dnsquery_resolved(query_data, hosts);

freeaddrinfo(res);

return TRUE;

}

#else /* defined(HAVE_GETADDRINFO) && defined(AI_NUMERICHOST) */

struct sockaddr_in sin;

if (inet_aton(query_data->hostname, &sin.sin_addr))

{

* The given "hostname" is actually an IP address, so we

* don't need to do anything.

GSList *hosts = NULL;

sin.sin_family = AF_INET;

sin.sin_port = htons(query_data->port);

hosts = g_slist_append(hosts, GINT_TO_POINTER(sizeof(sin)));

hosts = g_slist_append(hosts, g_memdup2(&sin, sizeof(sin)));

purple_dnsquery_resolved(query_data, hosts);

return TRUE;

}

#endif

return FALSE;

}

#ifdef USE_IDN

static gboolean

dns_str_is_ascii(const char *name)

{

guchar *c;

for (c = (guchar *)name; c && *c; ++c) {

if (*c > 0x7f)

return FALSE;

}

return TRUE;

}

#endif

#if defined(PURPLE_DNSQUERY_USE_FORK)

* Unix!

* Begin the DNS resolver child process functions.

#ifdef HAVE_SIGNAL_H

G_GNUC_NORETURN static void

trap_gdb_bug(int sig)

{

const char *message =

"Purple's DNS child got a SIGTRAP signal.\n"

"This can be caused by trying to run purple inside gdb.\n"

"There is a known gdb bug which prevents this. Supposedly purple\n"

"should have detected you were using gdb and used an ugly hack,\n"

"check cope_with_gdb_brokenness() in dnsquery.c.\n\n"

"For more info about this bug, see http://sources.redhat.com/ml/gdb/2001-07/msg00349.html\n";

fputs("\n* * *\n",stderr);

fputs(message,stderr);

fputs("* * *\n\n",stderr);

execlp("xmessage","xmessage","-center", message, NULL);

_exit(1);

}

#endif

static void

write_to_parent(int fd, const void *buf, size_t count)

{

ssize_t written;

written = write(fd, buf, count);

if (written < 0 || (gsize)written != count) {

if (written < 0)

fprintf(stderr, "dns[%d]: Error writing data to "

"parent: %s\n", getpid(), strerror(errno));

else

fprintf(stderr, "dns[%d]: Error: Tried to write %"

G_GSIZE_FORMAT " bytes to parent but instead "

"wrote %" G_GSIZE_FORMAT " bytes\n",

getpid(), count, written);

}

G_GNUC_NORETURN static void

purple_dnsquery_resolver_run(int child_out, int child_in, gboolean show_debug)

{

dns_params_t dns_params;

const size_t zero = 0;

int rc;

#ifdef HAVE_GETADDRINFO

struct addrinfo hints, *res, *tmp;

char servname[20];

#else

struct sockaddr_in sin;

const size_t addrlen = sizeof(sin);

#endif

char *hostname;

#ifdef HAVE_SIGNAL_H

purple_restore_default_signal_handlers();

signal(SIGTRAP, trap_gdb_bug);

#endif

* We resolve 1 host name for each iteration of this

* while loop.

* The top half of this reads in the hostname and port

* number from the socket with our parent. The bottom

* half of this resolves the IP (blocking) and sends

* the result back to our parent, when finished.

while (1) {

fd_set fds;

struct timeval tv = { .tv_sec = 20, .tv_usec = 0 };

FD_ZERO(&fds);

FD_SET(child_in, &fds);

rc = select(child_in + 1, &fds, NULL, NULL, &tv);

if (!rc) {

if (show_debug)

printf("dns[%d]: nobody needs me... =(\n", getpid());

break;

}

rc = read(child_in, &dns_params, sizeof(dns_params_t));

if (rc < 0) {

fprintf(stderr, "dns[%d]: Error: Could not read dns_params: "

"%s\n", getpid(), strerror(errno));

break;

}

if (rc == 0) {

if (show_debug)

printf("dns[%d]: Oops, father has gone, wait for me, wait...!\n", getpid());

_exit(0);

}

if (dns_params.hostname[0] == '\0') {

fprintf(stderr, "dns[%d]: Error: Parent requested resolution "

"of an empty hostname (port = %d)!!!\n", getpid(),

dns_params.port);

_exit(1);

}

#ifdef USE_IDN

if (!dns_str_is_ascii(dns_params.hostname)) {

rc = purple_network_convert_idn_to_ascii(dns_params.hostname, &hostname);

if (rc != 0) {

write_to_parent(child_out, &rc, sizeof(rc));

if (show_debug)

fprintf(stderr, "dns[%d] Error: IDN conversion returned "

"%d\n", getpid(), rc);

dns_params.hostname[0] = '\0';

break;

}

} else /* intentional to execute the g_strdup */

#endif

hostname = g_strdup(dns_params.hostname);

/* We have the hostname and port, now resolve the IP */

#ifdef HAVE_GETADDRINFO

g_snprintf(servname, sizeof(servname), "%d", dns_params.port);

memset(&hints, 0, sizeof(hints));

/* This is only used to convert a service

* name to a port number. As we know we are

* passing a number already, we know this

* value will not be really used by the C

* library.

hints.ai_socktype = SOCK_STREAM;

#ifdef AI_ADDRCONFIG

hints.ai_flags |= AI_ADDRCONFIG;

#endif /* AI_ADDRCONFIG */

rc = getaddrinfo(hostname, servname, &hints, &res);

write_to_parent(child_out, &rc, sizeof(rc));

if (rc != 0) {

if (show_debug)

printf("dns[%d] Error: getaddrinfo returned %d\n",

getpid(), rc);

dns_params.hostname[0] = '\0';

g_free(hostname);

hostname = NULL;

break;

}

tmp = res;

while (res) {

size_t ai_addrlen = res->ai_addrlen;

write_to_parent(child_out, &ai_addrlen, sizeof(ai_addrlen));

write_to_parent(child_out, res->ai_addr, res->ai_addrlen);

res = res->ai_next;

}

freeaddrinfo(tmp);

#else

struct hostent *hp;

if (!(hp = gethostbyname(hostname))) {

write_to_parent(child_out, &h_errno, sizeof(int));

close(child_out);

if (show_debug)

printf("DNS Error: %d\n", h_errno);

_exit(0);

}

memset(&sin, 0, sizeof(struct sockaddr_in));

memcpy(&sin.sin_addr.s_addr, hp->h_addr, hp->h_length);

sin.sin_family = hp->h_addrtype;

sin.sin_port = htons(dns_params.port);

rc = 0;

write_to_parent(child_out, &rc, sizeof(rc));

write_to_parent(child_out, &addrlen, sizeof(addrlen));

write_to_parent(child_out, &sin, addrlen);

#endif

write_to_parent(child_out, &zero, sizeof(zero));

dns_params.hostname[0] = '\0';

g_free(hostname);

hostname = NULL;

}

close(child_out);

close(child_in);

_exit(0);

}

* End the DNS resolver child process functions.

* Begin the functions for dealing with the DNS child processes.

static void

cope_with_gdb_brokenness(void)

{

#ifdef __linux__

static gboolean already_done = FALSE;

char s[256], e[512];

int n;

pid_t ppid;

if(already_done)

return;

already_done = TRUE;

ppid = getppid();

g_snprintf(s, sizeof(s), "/proc/%d/exe", ppid);

n = readlink(s, e, sizeof(e));

if(n < 0)

return;

e[MIN((gsize)n,sizeof(e)-1)] = '\0';

if(strstr(e,"gdb")) {

purple_debug_info("dns",

"Debugger detected, performing useless query...\n");

gethostbyname("x.x.x.x.x");

}

#endif

}

static void

purple_dnsquery_resolver_destroy(PurpleDnsQueryResolverProcess *resolver)

{

g_return_if_fail(resolver != NULL);

/* Keep this before the kill() call below. */

if (resolver->inpa != 0) {

purple_input_remove(resolver->inpa);

resolver->inpa = 0;

}

* We might as well attempt to kill our child process. It really

* doesn't matter if this fails, because children will expire on

* their own after a few seconds.

if (resolver->dns_pid > 0)

kill(resolver->dns_pid, SIGKILL);

close(resolver->fd_in);

close(resolver->fd_out);

g_free(resolver);

number_of_dns_children--;

}

static PurpleDnsQueryResolverProcess *

purple_dnsquery_resolver_new(gboolean show_debug)

{

PurpleDnsQueryResolverProcess *resolver;

int child_out[2], child_in[2];

/* Create pipes for communicating with the child process */

if (pipe(child_out) || pipe(child_in)) {

purple_debug_error("dns",

"Could not create pipes: %s\n", g_strerror(errno));

return NULL;

}

resolver = g_new(PurpleDnsQueryResolverProcess, 1);

resolver->inpa = 0;

cope_with_gdb_brokenness();

/* "Go fork and multiply." --Tommy Caldwell (Emily's dad, not the climber) */

resolver->dns_pid = fork();

/* If we are the child process... */

if (resolver->dns_pid == 0) {

/* We should not access the parent's side of the pipes, so close them */

close(child_out[0]);

close(child_in[1]);

purple_dnsquery_resolver_run(child_out[1], child_in[0], show_debug);

/* The thread calls _exit() rather than returning, so we never get here */

}

/* We should not access the child's side of the pipes, so close them */

close(child_out[1]);

close(child_in[0]);

if (resolver->dns_pid == -1) {

purple_debug_error("dns",

"Could not create child process for DNS: %s\n",

g_strerror(errno));

purple_dnsquery_resolver_destroy(resolver);

return NULL;

}

resolver->fd_out = child_out[0];

resolver->fd_in = child_in[1];

number_of_dns_children++;

purple_debug_info("dns",

"Created new DNS child %d, there are now %d children.\n",

resolver->dns_pid, number_of_dns_children);

return resolver;

}

/**

* @return TRUE if the request was sent succesfully. FALSE

* if the request could not be sent. This isn't

* necessarily an error. If the child has expired,

* for example, we won't be able to send the message.

static gboolean

send_dns_request_to_child(PurpleDnsQueryData *query_data,

PurpleDnsQueryResolverProcess *resolver)

{

pid_t pid;

dns_params_t dns_params;

ssize_t rc;

/* This waitpid might return the child's PID if it has recently

* exited, or it might return an error if it exited "long

* enough" ago that it has already been reaped; in either

* instance, we can't use it. */

pid = waitpid(resolver->dns_pid, NULL, WNOHANG);

if (pid > 0) {

purple_debug_warning("dns", "DNS child %d no longer exists\n",

resolver->dns_pid);

purple_dnsquery_resolver_destroy(resolver);

return FALSE;

} else if (pid < 0) {

purple_debug_warning("dns", "Wait for DNS child %d failed: %s\n",

resolver->dns_pid, g_strerror(errno));

purple_dnsquery_resolver_destroy(resolver);

return FALSE;

}

/* Copy the hostname and port into a single data structure */

strncpy(dns_params.hostname, query_data->hostname, sizeof(dns_params.hostname) - 1);

dns_params.hostname[sizeof(dns_params.hostname) - 1] = '\0';

dns_params.port = query_data->port;

/* Send the data structure to the child */

rc = write(resolver->fd_in, &dns_params, sizeof(dns_params));

if (rc < 0) {

purple_debug_error("dns", "Unable to write to DNS child %d: %s\n",

resolver->dns_pid, g_strerror(errno));

purple_dnsquery_resolver_destroy(resolver);

return FALSE;

}

if ((gsize)rc < sizeof(dns_params)) {

purple_debug_error("dns", "Tried to write %" G_GSSIZE_FORMAT

" bytes to child but only wrote %" G_GSSIZE_FORMAT "\n",

sizeof(dns_params), rc);

purple_dnsquery_resolver_destroy(resolver);

return FALSE;

}

purple_debug_info("dns",

"Successfully sent DNS request to child %d\n",

resolver->dns_pid);

query_data->resolver = resolver;

return TRUE;

}

static void host_resolved(gpointer data, gint source, PurpleInputCondition cond);

static void

handle_next_queued_request(void)

{

PurpleDnsQueryData *query_data;

PurpleDnsQueryResolverProcess *resolver;

if (queued_requests == NULL)

/* No more DNS queries, yay! */

return;

query_data = queued_requests->data;

queued_requests = g_slist_delete_link(queued_requests, queued_requests);

* If we have any children, attempt to have them perform the DNS

* query. If we're able to send the query then resolver will be

* set to the PurpleDnsQueryResolverProcess. Otherwise, resolver

* will be NULL and we'll need to create a new DNS request child.

while (free_dns_children != NULL)

{

resolver = free_dns_children->data;

free_dns_children = g_slist_remove(free_dns_children, resolver);

if (send_dns_request_to_child(query_data, resolver))

/* We found an acceptable child, yay */

break;

}

/* We need to create a new DNS request child */

if (query_data->resolver == NULL)

{

if (number_of_dns_children >= MAX_DNS_CHILDREN)

{

/* Apparently all our children are busy */

queued_requests = g_slist_prepend(queued_requests, query_data);

return;

}

resolver = purple_dnsquery_resolver_new(purple_debug_is_enabled());

if (resolver == NULL)

{

purple_dnsquery_failed(query_data, _("Unable to create new resolver process\n"));

return;

}

if (!send_dns_request_to_child(query_data, resolver))

{

purple_dnsquery_failed(query_data, _("Unable to send request to resolver process\n"));

return;

}

query_data->resolver->inpa = purple_input_add(query_data->resolver->fd_out,

PURPLE_INPUT_READ, host_resolved, query_data);

}

* End the functions for dealing with the DNS child processes.

static void

host_resolved(gpointer data, gint source, PurpleInputCondition cond)

{

PurpleDnsQueryData *query_data;

int rc, err;

GSList *hosts = NULL;

struct sockaddr *addr = NULL;

size_t addrlen;

char message[1024];

query_data = data;

purple_debug_info("dns", "Got response for '%s'\n", query_data->hostname);

purple_input_remove(query_data->resolver->inpa);

query_data->resolver->inpa = 0;

rc = read(query_data->resolver->fd_out, &err, sizeof(err));

if ((rc == 4) && (err != 0))

{

#ifdef HAVE_GETADDRINFO

g_snprintf(message, sizeof(message), _("Error resolving %s:\n%s"),

query_data->hostname, purple_gai_strerror(err));

#else

g_snprintf(message, sizeof(message), _("Error resolving %s: %d"),

query_data->hostname, err);

#endif

/* Re-read resolv.conf and friends in case DNS servers have changed */

res_init();

purple_dnsquery_failed(query_data, message);

} else if (rc > 0) {

/* Success! */

while (rc > 0) {

rc = read(query_data->resolver->fd_out, &addrlen, sizeof(addrlen));

if (rc > 0 && addrlen > 0 && addrlen < MAX_ADDR_RESPONSE_LEN) {

addr = g_malloc(addrlen);

rc = read(query_data->resolver->fd_out, addr, addrlen);

hosts = g_slist_append(hosts, GINT_TO_POINTER(addrlen));

hosts = g_slist_append(hosts, addr);

} else {

break;

}

/* wait4(resolver->dns_pid, NULL, WNOHANG, NULL); */

purple_dnsquery_resolved(query_data, hosts);

} else if (rc == -1) {

g_snprintf(message, sizeof(message), _("Error reading from resolver process:\n%s"), g_strerror(errno));

purple_dnsquery_failed(query_data, message);

} else if (rc == 0) {

g_snprintf(message, sizeof(message), _("Resolver process exited without answering our request"));

purple_dnsquery_failed(query_data, message);

}

handle_next_queued_request();

}

static void

resolve_host(PurpleDnsQueryData *query_data)

{

queued_requests = g_slist_append(queued_requests, query_data);

handle_next_queued_request();

}

#elif defined _WIN32 /* end PURPLE_DNSQUERY_USE_FORK */

* Windows!

static gboolean

dns_main_thread_cb(gpointer data)

{

PurpleDnsQueryData *query_data = data;

/* We're done, so purple_dnsquery_destroy() shouldn't think it is canceling an in-progress lookup */

query_data->resolver = NULL;

if (query_data->error_message != NULL)

purple_dnsquery_failed(query_data, query_data->error_message);

else

{

GSList *hosts;

/* We don't want purple_dns_query_resolved() to free(hosts) */

hosts = query_data->hosts;

query_data->hosts = NULL;

purple_dnsquery_resolved(query_data, hosts);

}

return FALSE;

}

static gpointer

dns_thread(gpointer data)

{

PurpleDnsQueryData *query_data;

#ifdef HAVE_GETADDRINFO

int rc;

struct addrinfo hints, *res, *tmp;

char servname[20];

#else

struct sockaddr_in sin;

struct hostent *hp;

#endif

char *hostname;

query_data = data;

#ifdef USE_IDN

if (!dns_str_is_ascii(query_data->hostname)) {

rc = purple_network_convert_idn_to_ascii(query_data->hostname, &hostname);

if (rc != 0) {

query_data->error_message = g_strdup_printf(_("Error converting %s "

"to punycode: %d"), query_data->hostname, rc);

/* back to main thread */

purple_timeout_add(0, dns_main_thread_cb, query_data);

return 0;

}

} else /* intentional fallthru */

#endif

hostname = g_strdup(query_data->hostname);

#ifdef HAVE_GETADDRINFO

g_snprintf(servname, sizeof(servname), "%d", query_data->port);

memset(&hints,0,sizeof(hints));

* This is only used to convert a service

* name to a port number. As we know we are

* passing a number already, we know this

* value will not be really used by the C

* library.

hints.ai_socktype = SOCK_STREAM;

#ifdef AI_ADDRCONFIG

hints.ai_flags |= AI_ADDRCONFIG;

#endif /* AI_ADDRCONFIG */

if ((rc = getaddrinfo(hostname, servname, &hints, &res)) == 0) {

tmp = res;

while(res) {

query_data->hosts = g_slist_append(query_data->hosts,

GSIZE_TO_POINTER(res->ai_addrlen));

query_data->hosts = g_slist_append(query_data->hosts,

g_memdup2(res->ai_addr, res->ai_addrlen));

res = res->ai_next;

}

freeaddrinfo(tmp);

} else {

query_data->error_message = g_strdup_printf(_("Error resolving %s:\n%s"), query_data->hostname, purple_gai_strerror(rc));

}

#else

if ((hp = gethostbyname(hostname))) {

memset(&sin, 0, sizeof(struct sockaddr_in));

memcpy(&sin.sin_addr.s_addr, hp->h_addr, hp->h_length);

sin.sin_family = hp->h_addrtype;

sin.sin_port = htons(query_data->port);

query_data->hosts = g_slist_append(query_data->hosts,

GSIZE_TO_POINTER(sizeof(sin)));

query_data->hosts = g_slist_append(query_data->hosts,

g_memdup2(&sin, sizeof(sin)));

} else {

query_data->error_message = g_strdup_printf(_("Error resolving %s: %d"), query_data->hostname, h_errno);

}

#endif

g_free(hostname);

/* back to main thread */

purple_timeout_add(0, dns_main_thread_cb, query_data);

return 0;

}

static void

resolve_host(PurpleDnsQueryData *query_data)

{

GError *err = NULL;

* Spin off a separate thread to perform the DNS lookup so

* that we don't block the UI.

query_data->resolver = g_thread_create(dns_thread,

query_data, FALSE, &err);

if (query_data->resolver == NULL)

{

char message[1024];

g_snprintf(message, sizeof(message), _("Thread creation failure: %s"),

(err && err->message) ? err->message : _("Unknown reason"));

g_error_free(err);

purple_dnsquery_failed(query_data, message);

}

#else /* not PURPLE_DNSQUERY_USE_FORK or _WIN32 */

* We weren't able to do anything fancier above, so use the

* fail-safe name resolution code, which is blocking.

static void

resolve_host(PurpleDnsQueryData *query_data)

{

struct sockaddr_in sin;

GSList *hosts = NULL;

struct hostent *hp;

gchar *hostname;

#ifdef USE_IDN

if (!dns_str_is_ascii(query_data->hostname)) {

int ret = purple_network_convert_idn_to_ascii(query_data->hostname,

&hostname);

if (ret != 0) {

char message[1024];

g_snprintf(message, sizeof(message), _("Error resolving %s: %d"),

query_data->hostname, ret);

purple_dnsquery_failed(query_data, message);

return;

}

} else /* fallthrough is intentional to the g_strdup */

#endif

hostname = g_strdup(query_data->hostname);

if(!(hp = gethostbyname(hostname))) {

char message[1024];

g_snprintf(message, sizeof(message), _("Error resolving %s: %d"),

query_data->hostname, h_errno);

purple_dnsquery_failed(query_data, message);

g_free(hostname);

return;

}

memset(&sin, 0, sizeof(struct sockaddr_in));

memcpy(&sin.sin_addr.s_addr, hp->h_addr, hp->h_length);

sin.sin_family = hp->h_addrtype;

g_free(hostname);

sin.sin_port = htons(query_data->port);

hosts = g_slist_append(hosts, GINT_TO_POINTER(sizeof(sin)));

hosts = g_slist_append(hosts, g_memdup2(&sin, sizeof(sin)));

purple_dnsquery_resolved(query_data, hosts);

}

#endif /* not PURPLE_DNSQUERY_USE_FORK or _WIN32 */

static gboolean

initiate_resolving(gpointer data)

{

PurpleDnsQueryData *query_data;

PurpleProxyType proxy_type;

query_data = data;

query_data->timeout = 0;

if (resolve_ip(query_data))

/* resolve_ip calls purple_dnsquery_resolved */

return FALSE;

proxy_type = purple_proxy_info_get_type(

purple_proxy_get_setup(query_data->account));

if (proxy_type == PURPLE_PROXY_TOR) {

purple_dnsquery_failed(query_data,

_("Aborting DNS lookup in Tor Proxy mode."));

return FALSE;

}

if (purple_dnsquery_ui_resolve(query_data))

/* The UI is handling the resolve; we're done */

return FALSE;

resolve_host(query_data);

return FALSE;

}

PurpleDnsQueryData *

purple_dnsquery_a_account(PurpleAccount *account, const char *hostname, int port,

PurpleDnsQueryConnectFunction callback, gpointer data)

{

PurpleDnsQueryData *query_data;

g_return_val_if_fail(hostname != NULL, NULL);

g_return_val_if_fail(port != 0, NULL);

g_return_val_if_fail(callback != NULL, NULL);

purple_debug_info("dnsquery", "Performing DNS lookup for %s\n", hostname);

query_data = g_new0(PurpleDnsQueryData, 1);

query_data->hostname = g_strdup(hostname);

g_strstrip(query_data->hostname);

query_data->port = port;

query_data->callback = callback;

query_data->data = data;

query_data->account = account;

if (*query_data->hostname == '\0')

{

purple_dnsquery_destroy(query_data);

g_return_val_if_reached(NULL);

}

query_data->timeout = purple_timeout_add(0, initiate_resolving, query_data);

return query_data;

}

PurpleDnsQueryData *

purple_dnsquery_a(const char *hostname, int port,

PurpleDnsQueryConnectFunction callback, gpointer data)

{

return purple_dnsquery_a_account(NULL, hostname, port, callback, data);

}

void

purple_dnsquery_destroy(PurpleDnsQueryData *query_data)

{

PurpleDnsQueryUiOps *ops = purple_dnsquery_get_ui_ops();

if (ops && ops->destroy)

ops->destroy(query_data);

#if defined(PURPLE_DNSQUERY_USE_FORK)

queued_requests = g_slist_remove(queued_requests, query_data);

if (query_data->resolver != NULL)

* This is only non-NULL when we're cancelling an in-progress

* query. Ideally we would tell our resolver child to stop

* resolving shit and then we would add it back to the

* free_dns_children linked list. However, it's hard to tell

* children stuff, they just don't listen. So we'll just

* kill the process and allow a new child to be started if we

* have more stuff to resolve.

purple_dnsquery_resolver_destroy(query_data->resolver);

#elif defined _WIN32 /* end PURPLE_DNSQUERY_USE_FORK */

if (query_data->resolver != NULL)

{

* It's not really possible to kill a thread. So instead we

* just set the callback to NULL and let the DNS lookup

* finish.

query_data->callback = NULL;

return;

}

while (query_data->hosts != NULL)

{

/* Discard the length... */

query_data->hosts = g_slist_remove(query_data->hosts, query_data->hosts->data);

/* Free the address... */

g_free(query_data->hosts->data);

query_data->hosts = g_slist_remove(query_data->hosts, query_data->hosts->data);

}

g_free(query_data->error_message);

#endif /* end _WIN32 */

if (query_data->timeout > 0)

purple_timeout_remove(query_data->timeout);

g_free(query_data->hostname);

g_free(query_data);

}

char *

purple_dnsquery_get_host(PurpleDnsQueryData *query_data)

{

g_return_val_if_fail(query_data != NULL, NULL);

return query_data->hostname;

}

unsigned short

purple_dnsquery_get_port(PurpleDnsQueryData *query_data)

{

g_return_val_if_fail(query_data != NULL, 0);

return query_data->port;

}

void

purple_dnsquery_set_ui_ops(PurpleDnsQueryUiOps *ops)

{

dns_query_ui_ops = ops;

}

PurpleDnsQueryUiOps *

purple_dnsquery_get_ui_ops(void)

{

/* It is perfectly acceptable for dns_query_ui_ops to be NULL; this just

* means that the default platform-specific implementation will be used.

return dns_query_ui_ops;

}

void

purple_dnsquery_init(void)

{

}

void

purple_dnsquery_uninit(void)

{

#if defined(PURPLE_DNSQUERY_USE_FORK)

while (free_dns_children != NULL)

{

purple_dnsquery_resolver_destroy(free_dns_children->data);

free_dns_children = g_slist_remove(free_dns_children, free_dns_children->data);

}

#endif /* end PURPLE_DNSQUERY_USE_FORK */

}

pidgin/pidgin