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+/**
+ * @file llavatarnamecache.cpp
+ * @brief Provides lookup of avatar SLIDs ("bobsmith123") and display names
+ * ("James Cook") from avatar UUIDs.
+ *
+ * $LicenseInfo:firstyear=2010&license=viewergpl$
+ *
+ * Copyright (c) 2010, Linden Research, Inc.
+ *
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab. Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ *
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ *
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ *
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+#include "linden_common.h"
+
+#include "llavatarnamecache.h"
+
+#include "llcachename.h" // we wrap this system
+#include "llframetimer.h"
+#include "llhttpclient.h"
+#include "llsd.h"
+#include "llsdserialize.h"
+
+#include <boost/tokenizer.hpp>
+
+#include <map>
+#include <set>
+
+namespace LLAvatarNameCache
+{
+ // Manual override for display names - can disable even if the region
+ // supports it.
+ bool sUseDisplayNames = true;
+
+ // Cache starts in a paused state until we can determine if the
+ // current region supports display names.
+ bool sRunning = false;
+
+ // Base lookup URL for name service.
+ // On simulator, loaded from indra.xml
+ // On viewer, usually a simulator capability (at People API team's request)
+ // Includes the trailing slash, like "http://pdp60.lindenlab.com:8000/agents/"
+ std::string sNameLookupURL;
+
+ // accumulated agent IDs for next query against service
+ typedef std::set<LLUUID> ask_queue_t;
+ ask_queue_t sAskQueue;
+
+ // agent IDs that have been requested, but with no reply
+ // maps agent ID to frame time request was made
+ typedef std::map<LLUUID, F64> pending_queue_t;
+ pending_queue_t sPendingQueue;
+
+ // Callbacks to fire when we received a name.
+ // May have multiple callbacks for a single ID, which are
+ // represented as multiple slots bound to the signal.
+ // Avoid copying signals via pointers.
+ typedef std::map<LLUUID, callback_signal_t*> signal_map_t;
+ signal_map_t sSignalMap;
+
+ // names we know about
+ typedef std::map<LLUUID, LLAvatarName> cache_t;
+ cache_t sCache;
+
+ // Send bulk lookup requests a few times a second at most
+ // only need per-frame timing resolution
+ LLFrameTimer sRequestTimer;
+
+ // Periodically clean out expired entries from the cache
+ //LLFrameTimer sEraseExpiredTimer;
+
+ //-----------------------------------------------------------------------
+ // Internal methods
+ //-----------------------------------------------------------------------
+
+ // Handle name response off network.
+ // Optionally skip adding to cache, used when this is a fallback to the
+ // legacy name system.
+ void processName(const LLUUID& agent_id,
+ const LLAvatarName& av_name,
+ bool add_to_cache);
+
+ void requestNamesViaCapability();
+
+ // Legacy name system callback
+ void legacyNameCallback(const LLUUID& agent_id,
+ const std::string& full_name,
+ bool is_group);
+
+ void requestNamesViaLegacy();
+
+ // Fill in an LLAvatarName with the legacy name data
+ void buildLegacyName(const std::string& full_name,
+ LLAvatarName* av_name);
+
+ // Do a single callback to a given slot
+ void fireSignal(const LLUUID& agent_id,
+ const callback_slot_t& slot,
+ const LLAvatarName& av_name);
+
+ // Is a request in-flight over the network?
+ bool isRequestPending(const LLUUID& agent_id);
+
+ // Erase expired names from cache
+ void eraseExpired();
+
+ bool expirationFromCacheControl(LLSD headers, F64 *expires);
+}
+
+/* Sample response:
+<?xml version="1.0"?>
+<llsd>
+ <map>
+ <key>agents</key>
+ <array>
+ <map>
+ <key>display_name_next_update</key>
+ <date>2010-04-16T21:34:02+00:00Z</date>
+ <key>display_name_expires</key>
+ <date>2010-04-16T21:32:26.142178+00:00Z</date>
+ <key>display_name</key>
+ <string>MickBot390 LLQABot</string>
+ <key>sl_id</key>
+ <string>mickbot390.llqabot</string>
+ <key>id</key>
+ <string>0012809d-7d2d-4c24-9609-af1230a37715</string>
+ <key>is_display_name_default</key>
+ <boolean>false</boolean>
+ </map>
+ <map>
+ <key>display_name_next_update</key>
+ <date>2010-04-16T21:34:02+00:00Z</date>
+ <key>display_name_expires</key>
+ <date>2010-04-16T21:32:26.142178+00:00Z</date>
+ <key>display_name</key>
+ <string>Bjork Gudmundsdottir</string>
+ <key>sl_id</key>
+ <string>sardonyx.linden</string>
+ <key>id</key>
+ <string>3941037e-78ab-45f0-b421-bd6e77c1804d</string>
+ <key>is_display_name_default</key>
+ <boolean>true</boolean>
+ </map>
+ </array>
+ </map>
+</llsd>
+*/
+
+class LLAvatarNameResponder : public LLHTTPClient::Responder
+{
+private:
+ // need to store agent ids that are part of this request in case of
+ // an error, so we can flag them as unavailable
+ std::vector<LLUUID> mAgentIDs;
+
+ // Need the headers to look up Expires: and Retry-After:
+ LLSD mHeaders;
+
+public:
+ LLAvatarNameResponder(const std::vector<LLUUID>& agent_ids)
+ : mAgentIDs(agent_ids),
+ mHeaders()
+ { }
+
+ /*virtual*/ void completedHeader(U32 status, const std::string& reason,
+ const LLSD& headers)
+ {
+ mHeaders = headers;
+ }
+
+ /*virtual*/ void result(const LLSD& content)
+ {
+ // Pull expiration out of headers if available
+ F64 expires = LLAvatarNameCache::nameExpirationFromHeaders(mHeaders);
+
+ LLSD agents = content["agents"];
+ LLSD::array_const_iterator it = agents.beginArray();
+ for ( ; it != agents.endArray(); ++it)
+ {
+ const LLSD& row = *it;
+ LLUUID agent_id = row["id"].asUUID();
+
+ LLAvatarName av_name;
+ av_name.fromLLSD(row);
+
+ // Use expiration time from header
+ av_name.mExpires = expires;
+
+ // Some avatars don't have explicit display names set
+ if (av_name.mDisplayName.empty())
+ {
+ av_name.mDisplayName = av_name.mUsername;
+ }
+
+ // cache it and fire signals
+ LLAvatarNameCache::processName(agent_id, av_name, true);
+ }
+
+ // Same logic as error response case
+ LLSD unresolved_agents = content["bad_ids"];
+ if (unresolved_agents.size() > 0)
+ {
+ const std::string DUMMY_NAME("\?\?\?");
+ LLAvatarName av_name;
+ av_name.mUsername = DUMMY_NAME;
+ av_name.mDisplayName = DUMMY_NAME;
+ av_name.mIsDisplayNameDefault = false;
+ av_name.mIsDummy = true;
+ av_name.mExpires = expires;
+
+ it = unresolved_agents.beginArray();
+ for ( ; it != unresolved_agents.endArray(); ++it)
+ {
+ const LLUUID& agent_id = *it;
+ // cache it and fire signals
+ LLAvatarNameCache::processName(agent_id, av_name, true);
+ }
+ }
+ }
+
+ /*virtual*/ void error(U32 status, const std::string& reason)
+ {
+ // We're going to construct a dummy record and cache it for a while,
+ // either briefly for a 503 Service Unavailable, or longer for other
+ // errors.
+ F64 retry_timestamp = errorRetryTimestamp(status);
+
+ // *NOTE: "??" starts trigraphs in C/C++, escape the question marks.
+ const std::string DUMMY_NAME("\?\?\?");
+ LLAvatarName av_name;
+ av_name.mUsername = DUMMY_NAME;
+ av_name.mDisplayName = DUMMY_NAME;
+ av_name.mIsDisplayNameDefault = false;
+ av_name.mIsDummy = true;
+ av_name.mExpires = retry_timestamp;
+
+ // Add dummy records for all agent IDs in this request
+ std::vector<LLUUID>::const_iterator it = mAgentIDs.begin();
+ for ( ; it != mAgentIDs.end(); ++it)
+ {
+ const LLUUID& agent_id = *it;
+ // cache it and fire signals
+ LLAvatarNameCache::processName(agent_id, av_name, true);
+ }
+ }
+
+ // Return time to retry a request that generated an error, based on
+ // error type and headers. Return value is seconds-since-epoch.
+ F64 errorRetryTimestamp(S32 status)
+ {
+ F64 now = LLFrameTimer::getTotalSeconds();
+
+ // Retry-After takes priority
+ LLSD retry_after = mHeaders["retry-after"];
+ if (retry_after.isDefined())
+ {
+ // We only support the delta-seconds type
+ S32 delta_seconds = retry_after.asInteger();
+ if (delta_seconds > 0)
+ {
+ // ...valid delta-seconds
+ return now + F64(delta_seconds);
+ }
+ }
+
+ // If no Retry-After, look for Cache-Control max-age
+ F64 expires = 0.0;
+ if (LLAvatarNameCache::expirationFromCacheControl(mHeaders, &expires))
+ {
+ return expires;
+ }
+
+ // No information in header, make a guess
+ if (status == 503)
+ {
+ // ...service unavailable, retry soon
+ const F64 SERVICE_UNAVAILABLE_DELAY = 600.0; // 10 min
+ return now + SERVICE_UNAVAILABLE_DELAY;
+ }
+ else
+ {
+ // ...other unexpected error
+ const F64 DEFAULT_DELAY = 3600.0; // 1 hour
+ return now + DEFAULT_DELAY;
+ }
+ }
+};
+
+void LLAvatarNameCache::processName(const LLUUID& agent_id,
+ const LLAvatarName& av_name,
+ bool add_to_cache)
+{
+ if (add_to_cache)
+ {
+ sCache[agent_id] = av_name;
+ }
+
+ sPendingQueue.erase(agent_id);
+
+ // signal everyone waiting on this name
+ signal_map_t::iterator sig_it = sSignalMap.find(agent_id);
+ if (sig_it != sSignalMap.end())
+ {
+ callback_signal_t* signal = sig_it->second;
+ (*signal)(agent_id, av_name);
+
+ sSignalMap.erase(agent_id);
+
+ delete signal;
+ signal = NULL;
+ }
+}
+
+void LLAvatarNameCache::requestNamesViaCapability()
+{
+ F64 now = LLFrameTimer::getTotalSeconds();
+
+ // URL format is like:
+ // http://pdp60.lindenlab.com:8000/agents/?ids=3941037e-78ab-45f0-b421-bd6e77c1804d&ids=0012809d-7d2d-4c24-9609-af1230a37715&ids=0019aaba-24af-4f0a-aa72-6457953cf7f0
+ //
+ // Apache can handle URLs of 4096 chars, but let's be conservative
+ const U32 NAME_URL_MAX = 4096;
+ const U32 NAME_URL_SEND_THRESHOLD = 3000;
+ std::string url;
+ url.reserve(NAME_URL_MAX);
+
+ std::vector<LLUUID> agent_ids;
+ agent_ids.reserve(128);
+
+ ask_queue_t::const_iterator it = sAskQueue.begin();
+ for ( ; it != sAskQueue.end(); ++it)
+ {
+ const LLUUID& agent_id = *it;
+
+ if (url.empty())
+ {
+ // ...starting new request
+ url += sNameLookupURL;
+ url += "?ids=";
+ }
+ else
+ {
+ // ...continuing existing request
+ url += "&ids=";
+ }
+ url += agent_id.asString();
+ agent_ids.push_back(agent_id);
+
+ // mark request as pending
+ sPendingQueue[agent_id] = now;
+
+ if (url.size() > NAME_URL_SEND_THRESHOLD)
+ {
+ //llinfos << "requestNames " << url << llendl;
+ LLHTTPClient::get(url, new LLAvatarNameResponder(agent_ids));
+ url.clear();
+ agent_ids.clear();
+ }
+ }
+
+ if (!url.empty())
+ {
+ //llinfos << "requestNames " << url << llendl;
+ LLHTTPClient::get(url, new LLAvatarNameResponder(agent_ids));
+ url.clear();
+ agent_ids.clear();
+ }
+
+ // We've moved all asks to the pending request queue
+ sAskQueue.clear();
+}
+
+void LLAvatarNameCache::legacyNameCallback(const LLUUID& agent_id,
+ const std::string& full_name,
+ bool is_group)
+{
+ // Construct a dummy record for this name. By convention, SLID is blank
+ // Never expires, but not written to disk, so lasts until end of session.
+ LLAvatarName av_name;
+ buildLegacyName(full_name, &av_name);
+
+ // Don't add to cache, the data already exists in the legacy name system
+ // cache and we don't want or need duplicate storage, because keeping the
+ // two copies in sync is complex.
+ processName(agent_id, av_name, false);
+}
+
+void LLAvatarNameCache::requestNamesViaLegacy()
+{
+ F64 now = LLFrameTimer::getTotalSeconds();
+ std::string full_name;
+ ask_queue_t::const_iterator it = sAskQueue.begin();
+ for (; it != sAskQueue.end(); ++it)
+ {
+ const LLUUID& agent_id = *it;
+
+ // Mark as pending first, just in case the callback is immediately
+ // invoked below. This should never happen in practice.
+ sPendingQueue[agent_id] = now;
+
+ gCacheName->get(agent_id, false, // legacy compatibility
+ boost::bind(&LLAvatarNameCache::legacyNameCallback,
+ _1, _2, _3));
+ }
+
+ // We've either answered immediately or moved all asks to the
+ // pending queue
+ sAskQueue.clear();
+}
+
+void LLAvatarNameCache::initClass(bool running)
+{
+ sRunning = running;
+}
+
+void LLAvatarNameCache::cleanupClass()
+{
+}
+
+void LLAvatarNameCache::importFile(std::istream& istr)
+{
+ LLSD data;
+ S32 parse_count = LLSDSerialize::fromXMLDocument(data, istr);
+ if (parse_count < 1) return;
+
+ // by convention LLSD storage is a map
+ // we only store one entry in the map
+ LLSD agents = data["agents"];
+
+ LLUUID agent_id;
+ LLAvatarName av_name;
+ LLSD::map_const_iterator it = agents.beginMap();
+ for ( ; it != agents.endMap(); ++it)
+ {
+ agent_id.set(it->first);
+ av_name.fromLLSD( it->second );
+ sCache[agent_id] = av_name;
+ }
+ // entries may have expired since we last ran the viewer, just
+ // clean them out now
+ eraseExpired();
+ llinfos << "loaded " << sCache.size() << llendl;
+}
+
+void LLAvatarNameCache::exportFile(std::ostream& ostr)
+{
+ LLSD agents;
+ cache_t::const_iterator it = sCache.begin();
+ for ( ; it != sCache.end(); ++it)
+ {
+ const LLUUID& agent_id = it->first;
+ const LLAvatarName& av_name = it->second;
+ if (!av_name.mIsDummy)
+ {
+ // key must be a string
+ agents[agent_id.asString()] = av_name.asLLSD();
+ }
+ }
+ LLSD data;
+ data["agents"] = agents;
+ LLSDSerialize::toPrettyXML(data, ostr);
+}
+
+void LLAvatarNameCache::setNameLookupURL(const std::string& name_lookup_url)
+{
+ sNameLookupURL = name_lookup_url;
+}
+
+bool LLAvatarNameCache::hasNameLookupURL()
+{
+ return !sNameLookupURL.empty();
+}
+
+void LLAvatarNameCache::idle()
+{
+ // By convention, start running at first idle() call
+ sRunning = true;
+
+ // *TODO: Possibly re-enabled this based on People API load measurements
+ // 100 ms is the threshold for "user speed" operations, so we can
+ // stall for about that long to batch up requests.
+ //const F32 SECS_BETWEEN_REQUESTS = 0.1f;
+ //if (!sRequestTimer.checkExpirationAndReset(SECS_BETWEEN_REQUESTS))
+ //{
+ // return;
+ //}
+
+ // Must be large relative to above
+
+ // No longer deleting expired entries, just re-requesting in the get
+ // this way first synchronous get call on an expired entry won't return
+ // legacy name. LF
+
+ //const F32 ERASE_EXPIRED_TIMEOUT = 60.f; // seconds
+ //if (sEraseExpiredTimer.checkExpirationAndReset(ERASE_EXPIRED_TIMEOUT))
+ //{
+ // eraseExpired();
+ //}
+
+ if (sAskQueue.empty())
+ {
+ return;
+ }
+
+ if (useDisplayNames())
+ {
+ requestNamesViaCapability();
+ }
+ else
+ {
+ // ...fall back to legacy name cache system
+ requestNamesViaLegacy();
+ }
+}
+
+bool LLAvatarNameCache::isRequestPending(const LLUUID& agent_id)
+{
+ const F64 PENDING_TIMEOUT_SECS = 5.0 * 60.0;
+ F64 now = LLFrameTimer::getTotalSeconds();
+ F64 expire_time = now - PENDING_TIMEOUT_SECS;
+
+ pending_queue_t::const_iterator it = sPendingQueue.find(agent_id);
+ if (it != sPendingQueue.end())
+ {
+ bool request_expired = (it->second < expire_time);
+ return !request_expired;
+ }
+ return false;
+}
+
+void LLAvatarNameCache::eraseExpired()
+{
+ F64 now = LLFrameTimer::getTotalSeconds();
+ cache_t::iterator it = sCache.begin();
+ while (it != sCache.end())
+ {
+ cache_t::iterator cur = it;
+ ++it;
+ const LLAvatarName& av_name = cur->second;
+ if (av_name.mExpires < now)
+ {
+ sCache.erase(cur);
+ }
+ }
+}
+
+void LLAvatarNameCache::buildLegacyName(const std::string& full_name,
+ LLAvatarName* av_name)
+{
+ llassert(av_name);
+ av_name->mUsername = "";
+ av_name->mDisplayName = full_name;
+ av_name->mIsDisplayNameDefault = true;
+ av_name->mIsDummy = true;
+ av_name->mExpires = F64_MAX;
+}
+
+// fills in av_name if it has it in the cache, even if expired (can check expiry time)
+// returns bool specifying if av_name was filled, false otherwise
+bool LLAvatarNameCache::get(const LLUUID& agent_id, LLAvatarName *av_name)
+{
+ if (sRunning)
+ {
+ // ...only do immediate lookups when cache is running
+ if (useDisplayNames())
+ {
+ // ...use display names cache
+ std::map<LLUUID,LLAvatarName>::iterator it = sCache.find(agent_id);
+ if (it != sCache.end())
+ {
+ *av_name = it->second;
+
+ // re-request name if entry is expired
+ if (av_name->mExpires < LLFrameTimer::getTotalSeconds())
+ {
+ if (!isRequestPending(agent_id))
+ {
+ sAskQueue.insert(agent_id);
+ }
+ }
+
+ return true;
+ }
+ }
+ else
+ {
+ // ...use legacy names cache
+ std::string full_name;
+ if (gCacheName->getFullName(agent_id, full_name))
+ {
+ buildLegacyName(full_name, av_name);
+ return true;
+ }
+ }
+ }
+
+ if (!isRequestPending(agent_id))
+ {
+ sAskQueue.insert(agent_id);
+ }
+
+ return false;
+}
+
+void LLAvatarNameCache::fireSignal(const LLUUID& agent_id,
+ const callback_slot_t& slot,
+ const LLAvatarName& av_name)
+{
+ callback_signal_t signal;
+ signal.connect(slot);
+ signal(agent_id, av_name);
+}
+
+void LLAvatarNameCache::get(const LLUUID& agent_id, callback_slot_t slot)
+{
+ if (sRunning)
+ {
+ // ...only do immediate lookups when cache is running
+ if (useDisplayNames())
+ {
+ // ...use new cache
+ std::map<LLUUID,LLAvatarName>::iterator it = sCache.find(agent_id);
+ if (it != sCache.end())
+ {
+ const LLAvatarName& av_name = it->second;
+
+ if (av_name.mExpires > LLFrameTimer::getTotalSeconds())
+ {
+ // ...name already exists in cache, fire callback now
+ fireSignal(agent_id, slot, av_name);
+
+ return;
+ }
+ }
+ }
+ else
+ {
+ // ...use old name system
+ std::string full_name;
+ if (gCacheName->getFullName(agent_id, full_name))
+ {
+ LLAvatarName av_name;
+ buildLegacyName(full_name, &av_name);
+ fireSignal(agent_id, slot, av_name);
+ return;
+ }
+ }
+ }
+
+ // schedule a request
+ if (!isRequestPending(agent_id))
+ {
+ sAskQueue.insert(agent_id);
+ }
+
+ // always store additional callback, even if request is pending
+ signal_map_t::iterator sig_it = sSignalMap.find(agent_id);
+ if (sig_it == sSignalMap.end())
+ {
+ // ...new callback for this id
+ callback_signal_t* signal = new callback_signal_t();
+ signal->connect(slot);
+ sSignalMap[agent_id] = signal;
+ }
+ else
+ {
+ // ...existing callback, bind additional slot
+ callback_signal_t* signal = sig_it->second;
+ signal->connect(slot);
+ }
+}
+
+
+void LLAvatarNameCache::setUseDisplayNames(bool use)
+{
+ if (use != sUseDisplayNames)
+ {
+ sUseDisplayNames = use;
+ // flush our cache
+ sCache.clear();
+ }
+}
+
+bool LLAvatarNameCache::useDisplayNames()
+{
+ // Must be both manually set on and able to look up names.
+ return sUseDisplayNames && !sNameLookupURL.empty();
+}
+
+void LLAvatarNameCache::erase(const LLUUID& agent_id)
+{
+ sCache.erase(agent_id);
+}
+
+void LLAvatarNameCache::fetch(const LLUUID& agent_id)
+{
+ // re-request, even if request is already pending
+ sAskQueue.insert(agent_id);
+}
+
+void LLAvatarNameCache::insert(const LLUUID& agent_id, const LLAvatarName& av_name)
+{
+ // *TODO: update timestamp if zero?
+ sCache[agent_id] = av_name;
+}
+
+F64 LLAvatarNameCache::nameExpirationFromHeaders(LLSD headers)
+{
+ F64 expires = 0.0;
+ if (expirationFromCacheControl(headers, &expires))
+ {
+ return expires;
+ }
+ else
+ {
+ // With no expiration info, default to an hour
+ const F64 DEFAULT_EXPIRES = 60.0 * 60.0;
+ F64 now = LLFrameTimer::getTotalSeconds();
+ return now + DEFAULT_EXPIRES;
+ }
+}
+
+bool LLAvatarNameCache::expirationFromCacheControl(LLSD headers, F64 *expires)
+{
+ // Allow the header to override the default
+ LLSD cache_control_header = headers["cache-control"];
+ if (cache_control_header.isDefined())
+ {
+ S32 max_age = 0;
+ std::string cache_control = cache_control_header.asString();
+ if (max_age_from_cache_control(cache_control, &max_age))
+ {
+ F64 now = LLFrameTimer::getTotalSeconds();
+ *expires = now + (F64)max_age;
+ return true;
+ }
+ }
+ return false;
+}
+
+static const std::string MAX_AGE("max-age");
+static const boost::char_separator<char> EQUALS_SEPARATOR("=");
+static const boost::char_separator<char> COMMA_SEPARATOR(",");
+
+bool max_age_from_cache_control(const std::string& cache_control, S32 *max_age)
+{
+ // Split the string on "," to get a list of directives
+ typedef boost::tokenizer<boost::char_separator<char> > tokenizer;
+ tokenizer directives(cache_control, COMMA_SEPARATOR);
+
+ tokenizer::iterator token_it = directives.begin();
+ for ( ; token_it != directives.end(); ++token_it)
+ {
+ // Tokens may have leading or trailing whitespace
+ std::string token = *token_it;
+ LLStringUtil::trim(token);
+
+ if (token.compare(0, MAX_AGE.size(), MAX_AGE) == 0)
+ {
+ // ...this token starts with max-age, so let's chop it up by "="
+ tokenizer subtokens(token, EQUALS_SEPARATOR);
+ tokenizer::iterator subtoken_it = subtokens.begin();
+
+ // Must have a token
+ if (subtoken_it == subtokens.end()) return false;
+ std::string subtoken = *subtoken_it;
+
+ // Must exactly equal "max-age"
+ LLStringUtil::trim(subtoken);
+ if (subtoken != MAX_AGE) return false;
+
+ // Must have another token
+ ++subtoken_it;
+ if (subtoken_it == subtokens.end()) return false;
+ subtoken = *subtoken_it;
+
+ // Must be a valid integer
+ // *NOTE: atoi() returns 0 for invalid values, so we have to
+ // check the string first.
+ // *TODO: Do servers ever send "0000" for zero? We don't handle it
+ LLStringUtil::trim(subtoken);
+ if (subtoken == "0")
+ {
+ *max_age = 0;
+ return true;
+ }
+ S32 val = atoi( subtoken.c_str() );
+ if (val > 0 && val < S32_MAX)
+ {
+ *max_age = val;
+ return true;
+ }
+ return false;
+ }
+ }
+ return false;
+}
+
+