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[or-cvs] r9117: Try to reconcile (except for whitespace) eventdns with versi (in tor/trunk: . doc src/or)
- To: or-cvs@xxxxxxxxxxxxx
- Subject: [or-cvs] r9117: Try to reconcile (except for whitespace) eventdns with versi (in tor/trunk: . doc src/or)
- From: nickm@xxxxxxxx
- Date: Fri, 15 Dec 2006 01:12:11 -0500 (EST)
- Delivered-to: archiver@seul.org
- Delivered-to: or-cvs-outgoing@seul.org
- Delivered-to: or-cvs@seul.org
- Delivery-date: Fri, 15 Dec 2006 01:13:09 -0500
- Reply-to: or-talk@xxxxxxxxxxxxx
- Sender: owner-or-cvs@xxxxxxxxxxxxx
Author: nickm
Date: 2006-12-15 01:12:01 -0500 (Fri, 15 Dec 2006)
New Revision: 9117
Modified:
tor/trunk/
tor/trunk/doc/TODO
tor/trunk/src/or/eventdns.c
tor/trunk/src/or/eventdns.h
tor/trunk/src/or/eventdns_tor.h
Log:
r11584@Kushana: nickm | 2006-12-15 01:10:45 -0500
Try to reconcile (except for whitespace) eventdns with version in libevent, so it is easier for me to send merges. These changes should be cosmetic. (Ha!)
Property changes on: tor/trunk
___________________________________________________________________
svk:merge ticket from /tor/trunk [r11584] on c95137ef-5f19-0410-b913-86e773d04f59
Modified: tor/trunk/doc/TODO
===================================================================
--- tor/trunk/doc/TODO 2006-12-15 05:12:52 UTC (rev 9116)
+++ tor/trunk/doc/TODO 2006-12-15 06:12:01 UTC (rev 9117)
@@ -134,6 +134,12 @@
- address_is_invalid_destination() is the right thing to call here
(and feel free to make that function smarter)
+d - Eventdns improvements
+ - Have a way to query for AAAA and A records simultaneously.
+ - Improve request API: At the very least, add the ability to construct
+ a more-or-less arbitrary request and get a response.
+ - (Can we suppress cnames? Should we?)
+
- Performance improvements
x - Better estimates in the directory of whether servers have good uptime
Modified: tor/trunk/src/or/eventdns.c
===================================================================
--- tor/trunk/src/or/eventdns.c 2006-12-15 05:12:52 UTC (rev 9116)
+++ tor/trunk/src/or/eventdns.c 2006-12-15 06:12:01 UTC (rev 9117)
@@ -7,16 +7,13 @@
* reformat the whitespace, add Tor dependencies, or so on.
*
* TODO:
- * - Have a way to query for AAAA and A records simultaneously.
- * - Improve request API: At the very least, add the ability to construct
- * a more-or-less arbitrary request and get a response.
- * - (Can we suppress cnames? Should we?)
* - Replace all externally visible magic numbers with #defined constants.
* - Write documentation for APIs of all external functions.
*/
/* Async DNS Library
* Adam Langley <agl@xxxxxxxxxxxxxxxxxx>
+ * http://www.imperialviolet.org/eventdns.html
* Public Domain code
*
* This software is Public Domain. To view a copy of the public domain dedication,
@@ -34,195 +31,9 @@
* the source verbatim in their source distributions)
*
* Version: 0.1b
- *
- *
- * Welcome, gentle reader
- *
- * Async DNS lookups are really a whole lot harder than they should be,
- * mostly stemming from the fact that the libc resolver has never been
- * very good at them. Before you use this library you should see if libc
- * can do the job for you with the modern async call getaddrinfo_a
- * (see http://www.imperialviolet.org/page25.html#e498). Otherwise,
- * please continue.
- *
- * This code is based on libevent and you must call event_init before
- * any of the APIs in this file. You must also seed the OpenSSL random
- * source if you are using OpenSSL for ids (see below).
- *
- * This library is designed to be included and shipped with your source
- * code. You statically link with it. You should also test for the
- * existence of strtok_r and define HAVE_STRTOK_R if you have it.
- *
- * The DNS protocol requires a good source of id numbers and these
- * numbers should be unpredictable for spoofing reasons. There are
- * three methods for generating them here and you must define exactly
- * one of them. In increasing order of preference:
- *
- * DNS_USE_GETTIMEOFDAY_FOR_ID:
- * Using the bottom 16 bits of the usec result from gettimeofday. This
- * is a pretty poor solution but should work anywhere.
- * DNS_USE_CPU_CLOCK_FOR_ID:
- * Using the bottom 16 bits of the nsec result from the CPU's time
- * counter. This is better, but may not work everywhere. Requires
- * POSIX realtime support and you'll need to link against -lrt on
- * glibc systems at least.
- * DNS_USE_OPENSSL_FOR_ID:
- * Uses the OpenSSL RAND_bytes call to generate the data. You must
- * have seeded the pool before making any calls to this library.
- *
- * The library keeps track of the state of nameservers and will avoid
- * them when they go down. Otherwise it will round robin between them.
- *
- * Quick start guide:
- * #include "eventdns.h"
- * void callback(int result, char type, int count, int ttl,
- * void *addresses, void *arg);
- * evdns_resolv_conf_parse(DNS_OPTIONS_ALL, "/etc/resolv.conf");
- * evdns_resolve("www.hostname.com", 0, callback, NULL);
- *
- * When the lookup is complete the callback function is called. The
- * first argument will be one of the DNS_ERR_* defines in eventdns.h.
- * Hopefully it will be DNS_ERR_NONE, in which case type will be
- * DNS_IPv4_A, count will be the number of IP addresses, ttl is the time
- * which the data can be cached for (in seconds), addresses will point
- * to an array of uint32_t's and arg will be whatever you passed to
- * evdns_resolve.
- *
- * Searching:
- *
- * In order for this library to be a good replacement for glibc's resolver it
- * supports searching. This involves setting a list of default domains, in
- * which names will be queried for. The number of dots in the query name
- * determines the order in which this list is used.
- *
- * Searching appears to be a single lookup from the point of view of the API,
- * although many DNS queries may be generated from a single call to
- * evdns_resolve. Searching can also drastically slow down the resolution
- * of names.
- *
- * To disable searching:
- * 1. Never set it up. If you never call evdns_resolv_conf_parse or
- * evdns_search_add then no searching will occur.
- *
- * 2. If you do call evdns_resolv_conf_parse then don't pass
- * DNS_OPTION_SEARCH (or DNS_OPTIONS_ALL, which implies it).
- *
- * 3. When calling evdns_resolve, pass the DNS_QUERY_NO_SEARCH flag.
- *
- * The order of searches depends on the number of dots in the name. If the
- * number is greater than the ndots setting then the names is first tried
- * globally. Otherwise each search domain is appended in turn.
- *
- * The ndots setting can either be set from a resolv.conf, or by calling
- * evdns_search_ndots_set.
- *
- * For example, with ndots set to 1 (the default) and a search domain list of
- * ["myhome.net"]:
- * Query: www
- * Order: www.myhome.net, www.
- *
- * Query: www.abc
- * Order: www.abc., www.abc.myhome.net
- *
- * API reference:
- *
- * int evdns_nameserver_add(unsigned long int address)
- * Add a nameserver. The address should be an IP address in
- * network byte order. The type of address is chosen so that
- * it matches in_addr.s_addr.
- * Returns non-zero on error.
- *
- * int evdns_nameserver_ip_add(const char *ip_as_string)
- * This wraps the above function by parsing a string as an IP
- * address and adds it as a nameserver.
- * Returns non-zero on error
- *
- * int evdns_resolve(const char *name, int flags,
- * evdns_callback_type callback,
- * void *ptr)
- * Resolve a name. The name parameter should be a DNS name.
- * The flags parameter should be 0, or DNS_QUERY_NO_SEARCH
- * which disables searching for this query. (see defn of
- * searching above).
- *
- * The callback argument is a function which is called when
- * this query completes and ptr is an argument which is passed
- * to that callback function.
- *
- * Returns non-zero on error
- *
- * void evdns_search_clear()
- * Clears the list of search domains
- *
- * void evdns_search_add(const char *domain)
- * Add a domain to the list of search domains
- *
- * void evdns_search_ndots_set(int ndots)
- * Set the number of dots which, when found in a name, causes
- * the first query to be without any search domain.
- *
- * int evdns_count_nameservers(void)
- * Return the number of configured nameservers (not necessarily the
- * number of running nameservers). This is useful for double-checking
- * whether our calls to the various nameserver configuration functions
- * have been successful.
- *
- * int evdns_clear_nameservers_and_suspend(void)
- * Remove all currently configured nameservers, and suspend all pending
- * resolves. Resolves will not necessarily be re-attempted until
- * evdns_resume() is called.
- *
- * int evdns_resume(void)
- * Re-attempt resolves left in limbo after an earlier call to
- * evdns_clear_nameservers_and_suspend().
- *
- * int evdns_config_windows_nameservers(void)
- * Attempt to configure a set of nameservers based on platform settings on
- * a win32 host. Preferentially tries to use GetNetworkParams; if that fails,
- * looks in the registry. Returns 0 on success, nonzero on failure.
- *
- * int evdns_resolv_conf_parse(int flags, const char *filename)
- * Parse a resolv.conf like file from the given filename.
- *
- * See the man page for resolv.conf for the format of this file.
- * The flags argument determines what information is parsed from
- * this file:
- * DNS_OPTION_SEARCH - domain, search and ndots options
- * DNS_OPTION_NAMESERVERS - nameserver lines
- * DNS_OPTION_MISC - timeout and attempts options
- * DNS_OPTIONS_ALL - all of the above
- * The following directives are not parsed from the file:
- * sortlist, rotate, no-check-names, inet6, debug
- *
- * Returns non-zero on error:
- * 0 no errors
- * 1 failed to open file
- * 2 failed to stat file
- * 3 file too large
- * 4 out of memory
- * 5 short read from file
- *
- * Internals:
- *
- * Requests are kept in two queues. The first is the inflight queue. In
- * this queue requests have an allocated transaction id and nameserver.
- * They will soon be transmitted if they haven't already been.
- *
- * The second is the waiting queue. The size of the inflight ring is
- * limited and all other requests wait in waiting queue for space. This
- * bounds the number of concurrent requests so that we don't flood the
- * nameserver. Several algorithms require a full walk of the inflight
- * queue and so bounding its size keeps thing going nicely under huge
- * (many thousands of requests) loads.
- *
- * If a nameserver loses too many requests it is considered down and we
- * try not to use it. After a while we send a probe to that nameserver
- * (a lookup for google.com) and, if it replies, we consider it working
- * again. If the nameserver fails a probe we wait longer to try again
- * with the next probe.
*/
-#include "eventdns.h"
+#include <sys/types.h>
#include "eventdns_tor.h"
//#define NDEBUG
#include "../common/torint.h"
@@ -259,10 +70,11 @@
#define _FORTIFY_SOURCE 3
#include <string.h>
-#include <sys/types.h>
#include <fcntl.h>
#include <sys/time.h>
-// #include <stdint.h>
+#ifdef HAVE_STDINT_H
+#include <stdint.h>
+#endif
#include <stdlib.h>
#include <string.h>
#include <errno.h>
@@ -274,6 +86,7 @@
#include <stdio.h>
#include <stdarg.h>
+#include "eventdns.h"
#ifdef WIN32
#include <windows.h>
#include <winsock2.h>
@@ -312,8 +125,6 @@
#define u16 uint16_t
#define u8 uint8_t
-#include "eventdns.h"
-
#define MAX_ADDRS 4 // maximum number of addresses from a single packet
// which we bother recording
@@ -502,7 +313,7 @@
static void server_port_free(struct evdns_server_port *port);
static void server_port_ready_callback(int fd, short events, void *arg);
-#if defined(MS_WINDOWS) || defined(WIN32)
+#ifdef WIN32
static int
last_error(int sock)
{
@@ -585,7 +396,7 @@
if (!evdns_log_fn)
return;
va_start(args,fmt);
-#if defined(MS_WINDOWS) || defined(WIN32)
+#ifdef WIN32
_vsnprintf(buf, sizeof(buf), fmt, args);
#else
vsnprintf(buf, sizeof(buf), fmt, args);
@@ -912,9 +723,9 @@
name_parse(u8 *packet, int length, int *idx, char *name_out, int name_out_len) {
int name_end = -1;
int j = *idx;
-#define GET32(x) do { if (j + 4 > length) return -1; memcpy(&_t32, packet + j, 4); j += 4; x = ntohl(_t32); } while(0);
-#define GET16(x) do { if (j + 2 > length) return -1; memcpy(&_t, packet + j, 2); j += 2; x = ntohs(_t); } while(0);
-#define GET8(x) do { if (j >= length) return -1; x = packet[j++]; } while(0);
+#define GET32(x) do { if (j + 4 > length) goto err; memcpy(&_t32, packet + j, 4); j += 4; x = ntohl(_t32); } while(0);
+#define GET16(x) do { if (j + 2 > length) goto err; memcpy(&_t, packet + j, 2); j += 2; x = ntohs(_t); } while(0);
+#define GET8(x) do { if (j >= length) goto err; x = packet[j++]; } while(0);
char *cp = name_out;
const char *const end = name_out + name_out_len;
@@ -955,6 +766,8 @@
else
*idx = name_end;
return 0;
+ err:
+ return -1;
}
// parses a raw request from a nameserver.
@@ -968,7 +781,7 @@
u16 trans_id, flags, questions, answers, authority, additional, datalength;
u32 ttl, ttl_r = 0xffffffff;
struct reply reply;
- struct request *req = NULL;
+ struct request *req;
unsigned int i;
GET16(trans_id);
@@ -977,16 +790,9 @@
GET16(answers);
GET16(authority);
GET16(additional);
- (void) authority;
- (void) additional;
+ (void) authority; /* suppress "unused variable" warnings. */
+ (void) additional; /* suppress "unused variable" warnings. */
- // This macro skips a name in the DNS reply.
-#define SKIP_NAME \
- do { tmp_name[0] = '\0'; \
- if (name_parse(packet, length, &j, tmp_name, sizeof(tmp_name))<0) \
- return -1; \
- } while(0);
-
req = request_find_from_trans_id(trans_id);
if (!req) return -1;
// XXXX should the other return points also call reply_handle? -NM
@@ -1001,6 +807,13 @@
}
// if (!answers) return; // must have an answer of some form
+ // This macro skips a name in the DNS reply.
+#define SKIP_NAME \
+ do { tmp_name[0] = '\0'; \
+ if (name_parse(packet, length, &j, tmp_name, sizeof(tmp_name))<0) \
+ goto err; \
+ } while(0);
+
reply.type = req->request_type;
// skip over each question in the reply
@@ -1079,11 +892,9 @@
reply_handle(req, flags, ttl_r, &reply);
return 0;
+ err:
+ return -1;
}
-#undef SKIP_NAME
-#undef GET32
-#undef GET16
-#undef GET8
// Parse a raw request (packet,length) sent to a nameserver port (port) from
// a DNS client (addr,addrlen), and if it's well-formed, call the corresponding
@@ -1095,9 +906,6 @@
u16 _t; // used by the macros
char tmp_name[256]; // used by the macros
-#define GET16(x) do { if (j + 2 > length) goto err; memcpy(&_t, packet + j, 2); j += 2; x = ntohs(_t); } while(0);
-#define GET8(x) do { if (j >= length) goto err; x = packet[j++]; } while(0);
-
int i;
u16 trans_id, flags, questions, answers, authority, additional;
struct server_request *server_req = NULL;
@@ -1163,9 +971,12 @@
free(server_req);
}
return -1;
-}
+
+#undef SKIP_NAME
+#undef GET32
#undef GET16
#undef GET8
+}
// Try to choose a strong transaction id which isn't already in flight
static u16
@@ -1463,6 +1274,13 @@
memcpy(buf + j, &_t, 2); \
j += 2; \
} while (0)
+#define APPEND32(x) do { \
+ if (j + 4 > (off_t)buf_len) \
+ goto overflow; \
+ _t32 = htonl(x); \
+ memcpy(buf + j, &_t32, 4); \
+ j += 4; \
+ } while (0)
if (name_len > 255) return -2;
@@ -1522,20 +1340,12 @@
//
// Returns the amount of space used. Negative on error.
static int
-evdns_request_data_build(const char *const name, const int name_len, const u16 trans_id,
- const u16 type, const u16 class,
+evdns_request_data_build(const char *const name, const int name_len,
+ const u16 trans_id, const u16 type, const u16 class,
u8 *const buf, size_t buf_len) {
off_t j = 0; // current offset into buf
u16 _t; // used by the macros
-#define APPEND32(x) do { \
- if (j + 4 > (off_t)buf_len) \
- goto overflow; \
- _t32 = htonl(x); \
- memcpy(buf + j, &_t32, 4); \
- j += 4; \
- } while (0)
-
APPEND16(trans_id);
APPEND16(0x0100); // standard query, recusion needed
APPEND16(1); // one question
@@ -2031,8 +1841,8 @@
evtimer_set(&req->timeout_event, evdns_request_timeout_callback, req);
if (evtimer_add(&req->timeout_event, &global_timeout) < 0) {
log(EVDNS_LOG_WARN,
- "Error from libevent when adding timer for "
- "request %lx", (unsigned long) req);
+ "Error from libevent when adding timer for request %lx",
+ (unsigned long) req);
// ???? Do more?
}
req->tx_count++;
@@ -2159,6 +1969,7 @@
return 0;
}
+
// exported function
int
evdns_resume(void)
@@ -2190,7 +2001,7 @@
ns->socket = socket(PF_INET, SOCK_DGRAM, 0);
if (ns->socket < 0) { err = 1; goto out1; }
-#if defined(MS_WINDOWS) || defined(WIN32)
+#ifdef WIN32
{
u_long nonblocking = 1;
ioctlsocket(ns->socket, FIONBIO, &nonblocking);
@@ -2342,7 +2153,7 @@
request_submit(req);
return (0);
} else {
- return search_request_new(TYPE_A, name, flags, callback, ptr);
+ return (search_request_new(TYPE_A, name, flags, callback, ptr));
}
}
@@ -2358,7 +2169,7 @@
request_submit(req);
return (0);
} else {
- return search_request_new(TYPE_AAAA, name, flags, callback, ptr);
+ return (search_request_new(TYPE_AAAA, name, flags, callback, ptr));
}
}
@@ -2386,7 +2197,6 @@
struct request *req;
int i;
assert(in);
-
cp = buf;
for (i=0; i < 16; ++i) {
u8 byte = in->s6_addr[i];
@@ -2404,6 +2214,7 @@
return 0;
}
+
/////////////////////////////////////////////////////////////////////
// Search support
//
@@ -2556,7 +2367,7 @@
// we ran off the end of the list and still didn't find the requested string
abort();
- return NULL; /* unreachable. */
+ return NULL; /* unreachable; stops warnings in some compilers. */
}
static int
@@ -2806,7 +2617,7 @@
return err;
}
-#if defined(MS_WINDOWS) || defined(WIN32)
+#ifdef WIN32
// Add multiple nameservers from a space-or-comma-separated list.
static int
evdns_nameserver_ip_add_line(const char *ips) {
@@ -2861,7 +2672,6 @@
buf = malloc(size);
if (!buf) { status = 4; goto done; }
- }
fixed = buf;
r = fn(fixed, &size);
if (r != ERROR_SUCCESS && r != ERROR_BUFFER_OVERFLOW) {
@@ -2900,7 +2710,6 @@
}
if (!added_any) {
- //should we ever get here? - mikec
log(EVDNS_LOG_DEBUG, "No nameservers added.");
status = -1;
}
@@ -3006,7 +2815,7 @@
evdns_init(void)
{
int res = 0;
-#if defined(MS_WINDOWS) || defined(WIN32)
+#ifdef WIN32
evdns_config_windows_nameservers();
#else
res = evdns_resolv_conf_parse(DNS_OPTIONS_ALL, "/etc/resolv.conf");
Modified: tor/trunk/src/or/eventdns.h
===================================================================
--- tor/trunk/src/or/eventdns.h 2006-12-15 05:12:52 UTC (rev 9116)
+++ tor/trunk/src/or/eventdns.h 2006-12-15 06:12:01 UTC (rev 9117)
@@ -1,4 +1,12 @@
-/* This software is Public Domain. To view a copy of the public domain dedication,
+
+/*
+ * The original DNS code is due to Adam Langley with heavy
+ * modifications by Nick Mathewson. Adam put his DNS software in the
+ * public domain. You can find his original copyright below. Please,
+ * aware that the code as part of libevent is governed by the 3-clause
+ * BSD license above.
+ *
+ * This software is Public Domain. To view a copy of the public domain dedication,
* visit http://creativecommons.org/licenses/publicdomain/ or send a letter to
* Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.
*
@@ -13,6 +21,193 @@
* the source verbatim in their source distributions)
*/
+/*
+ * Welcome, gentle reader
+ *
+ * Async DNS lookups are really a whole lot harder than they should be,
+ * mostly stemming from the fact that the libc resolver has never been
+ * very good at them. Before you use this library you should see if libc
+ * can do the job for you with the modern async call getaddrinfo_a
+ * (see http://www.imperialviolet.org/page25.html#e498). Otherwise,
+ * please continue.
+ *
+ * This code is based on libevent and you must call event_init before
+ * any of the APIs in this file. You must also seed the OpenSSL random
+ * source if you are using OpenSSL for ids (see below).
+ *
+ * This library is designed to be included and shipped with your source
+ * code. You statically link with it. You should also test for the
+ * existence of strtok_r and define HAVE_STRTOK_R if you have it.
+ *
+ * The DNS protocol requires a good source of id numbers and these
+ * numbers should be unpredictable for spoofing reasons. There are
+ * three methods for generating them here and you must define exactly
+ * one of them. In increasing order of preference:
+ *
+ * DNS_USE_GETTIMEOFDAY_FOR_ID:
+ * Using the bottom 16 bits of the usec result from gettimeofday. This
+ * is a pretty poor solution but should work anywhere.
+ * DNS_USE_CPU_CLOCK_FOR_ID:
+ * Using the bottom 16 bits of the nsec result from the CPU's time
+ * counter. This is better, but may not work everywhere. Requires
+ * POSIX realtime support and you'll need to link against -lrt on
+ * glibc systems at least.
+ * DNS_USE_OPENSSL_FOR_ID:
+ * Uses the OpenSSL RAND_bytes call to generate the data. You must
+ * have seeded the pool before making any calls to this library.
+ *
+ * The library keeps track of the state of nameservers and will avoid
+ * them when they go down. Otherwise it will round robin between them.
+ *
+ * Quick start guide:
+ * #include "evdns.h"
+ * void callback(int result, char type, int count, int ttl,
+ * void *addresses, void *arg);
+ * evdns_resolv_conf_parse(DNS_OPTIONS_ALL, "/etc/resolv.conf");
+ * evdns_resolve("www.hostname.com", 0, callback, NULL);
+ *
+ * When the lookup is complete the callback function is called. The
+ * first argument will be one of the DNS_ERR_* defines in evdns.h.
+ * Hopefully it will be DNS_ERR_NONE, in which case type will be
+ * DNS_IPv4_A, count will be the number of IP addresses, ttl is the time
+ * which the data can be cached for (in seconds), addresses will point
+ * to an array of uint32_t's and arg will be whatever you passed to
+ * evdns_resolve.
+ *
+ * Searching:
+ *
+ * In order for this library to be a good replacement for glibc's resolver it
+ * supports searching. This involves setting a list of default domains, in
+ * which names will be queried for. The number of dots in the query name
+ * determines the order in which this list is used.
+ *
+ * Searching appears to be a single lookup from the point of view of the API,
+ * although many DNS queries may be generated from a single call to
+ * evdns_resolve. Searching can also drastically slow down the resolution
+ * of names.
+ *
+ * To disable searching:
+ * 1. Never set it up. If you never call evdns_resolv_conf_parse or
+ * evdns_search_add then no searching will occur.
+ *
+ * 2. If you do call evdns_resolv_conf_parse then don't pass
+ * DNS_OPTION_SEARCH (or DNS_OPTIONS_ALL, which implies it).
+ *
+ * 3. When calling evdns_resolve, pass the DNS_QUERY_NO_SEARCH flag.
+ *
+ * The order of searches depends on the number of dots in the name. If the
+ * number is greater than the ndots setting then the names is first tried
+ * globally. Otherwise each search domain is appended in turn.
+ *
+ * The ndots setting can either be set from a resolv.conf, or by calling
+ * evdns_search_ndots_set.
+ *
+ * For example, with ndots set to 1 (the default) and a search domain list of
+ * ["myhome.net"]:
+ * Query: www
+ * Order: www.myhome.net, www.
+ *
+ * Query: www.abc
+ * Order: www.abc., www.abc.myhome.net
+ *
+ * API reference:
+ *
+ * int evdns_nameserver_add(unsigned long int address)
+ * Add a nameserver. The address should be an IP address in
+ * network byte order. The type of address is chosen so that
+ * it matches in_addr.s_addr.
+ * Returns non-zero on error.
+ *
+ * int evdns_nameserver_ip_add(const char *ip_as_string)
+ * This wraps the above function by parsing a string as an IP
+ * address and adds it as a nameserver.
+ * Returns non-zero on error
+ *
+ * int evdns_resolve(const char *name, int flags,
+ * evdns_callback_type callback,
+ * void *ptr)
+ * Resolve a name. The name parameter should be a DNS name.
+ * The flags parameter should be 0, or DNS_QUERY_NO_SEARCH
+ * which disables searching for this query. (see defn of
+ * searching above).
+ *
+ * The callback argument is a function which is called when
+ * this query completes and ptr is an argument which is passed
+ * to that callback function.
+ *
+ * Returns non-zero on error
+ *
+ * void evdns_search_clear()
+ * Clears the list of search domains
+ *
+ * void evdns_search_add(const char *domain)
+ * Add a domain to the list of search domains
+ *
+ * void evdns_search_ndots_set(int ndots)
+ * Set the number of dots which, when found in a name, causes
+ * the first query to be without any search domain.
+ *
+ * int evdns_count_nameservers(void)
+ * Return the number of configured nameservers (not necessarily the
+ * number of running nameservers). This is useful for double-checking
+ * whether our calls to the various nameserver configuration functions
+ * have been successful.
+ *
+ * int evdns_clear_nameservers_and_suspend(void)
+ * Remove all currently configured nameservers, and suspend all pending
+ * resolves. Resolves will not necessarily be re-attempted until
+ * evdns_resume() is called.
+ *
+ * int evdns_resume(void)
+ * Re-attempt resolves left in limbo after an earlier call to
+ * evdns_clear_nameservers_and_suspend().
+ *
+ * int evdns_config_windows_nameservers(void)
+ * Attempt to configure a set of nameservers based on platform settings on
+ * a win32 host. Preferentially tries to use GetNetworkParams; if that fails,
+ * looks in the registry. Returns 0 on success, nonzero on failure.
+ *
+ * int evdns_resolv_conf_parse(int flags, const char *filename)
+ * Parse a resolv.conf like file from the given filename.
+ *
+ * See the man page for resolv.conf for the format of this file.
+ * The flags argument determines what information is parsed from
+ * this file:
+ * DNS_OPTION_SEARCH - domain, search and ndots options
+ * DNS_OPTION_NAMESERVERS - nameserver lines
+ * DNS_OPTION_MISC - timeout and attempts options
+ * DNS_OPTIONS_ALL - all of the above
+ * The following directives are not parsed from the file:
+ * sortlist, rotate, no-check-names, inet6, debug
+ *
+ * Returns non-zero on error:
+ * 0 no errors
+ * 1 failed to open file
+ * 2 failed to stat file
+ * 3 file too large
+ * 4 out of memory
+ * 5 short read from file
+ *
+ * Internals:
+ *
+ * Requests are kept in two queues. The first is the inflight queue. In
+ * this queue requests have an allocated transaction id and nameserver.
+ * They will soon be transmitted if they haven't already been.
+ *
+ * The second is the waiting queue. The size of the inflight ring is
+ * limited and all other requests wait in waiting queue for space. This
+ * bounds the number of concurrent requests so that we don't flood the
+ * nameserver. Several algorithms require a full walk of the inflight
+ * queue and so bounding its size keeps thing going nicely under huge
+ * (many thousands of requests) loads.
+ *
+ * If a nameserver loses too many requests it is considered down and we
+ * try not to use it. After a while we send a probe to that nameserver
+ * (a lookup for google.com) and, if it replies, we consider it working
+ * again. If the nameserver fails a probe we wait longer to try again
+ * with the next probe.
+ */
+
#ifndef EVENTDNS_H
#define EVENTDNS_H
Modified: tor/trunk/src/or/eventdns_tor.h
===================================================================
--- tor/trunk/src/or/eventdns_tor.h 2006-12-15 05:12:52 UTC (rev 9116)
+++ tor/trunk/src/or/eventdns_tor.h 2006-12-15 06:12:01 UTC (rev 9117)
@@ -10,4 +10,10 @@
#ifdef MS_WINDOWS
#define inline __inline
#endif
+#include "../common/torint.h"
+#if defined(MS_WINDOWS) && !defined(WIN32)
+/* How did _this_ happen? */
+#define WIN32
+#endif
+