mosesdecoder/moses/LM/Remote.cpp
2012-11-12 19:56:18 +00:00

145 lines
3.7 KiB
C++

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include "Remote.h"
#include "moses/Factor.h"
namespace Moses
{
const Factor* LanguageModelRemote::BOS = NULL;
const Factor* LanguageModelRemote::EOS = (LanguageModelRemote::BOS + 1);
bool LanguageModelRemote::Load(const std::string &filePath
, FactorType factorType
, size_t nGramOrder)
{
m_factorType = factorType;
m_nGramOrder = nGramOrder;
int cutAt = filePath.find(':',0);
std::string host = filePath.substr(0,cutAt);
//std::cerr << "port string = '" << filePath.substr(cutAt+1,filePath.size()-cutAt) << "'\n";
int port = atoi(filePath.substr(cutAt+1,filePath.size()-cutAt).c_str());
bool good = start(host,port);
if (!good) {
std::cerr << "failed to connect to lm server on " << host << " on port " << port << std::endl;
}
ClearSentenceCache();
return good;
}
bool LanguageModelRemote::start(const std::string& host, int port)
{
//std::cerr << "host = " << host << ", port = " << port << "\n";
sock = socket(AF_INET, SOCK_STREAM, 0);
hp = gethostbyname(host.c_str());
if (hp==NULL) {
herror("gethostbyname failed");
exit(1);
}
bzero((char *)&server, sizeof(server));
bcopy(hp->h_addr, (char *)&server.sin_addr, hp->h_length);
server.sin_family = hp->h_addrtype;
server.sin_port = htons(port);
int errors = 0;
while (connect(sock, (struct sockaddr *)&server, sizeof(server)) < 0) {
//std::cerr << "Error: connect()\n";
sleep(1);
errors++;
if (errors > 5) return false;
}
return true;
}
LMResult LanguageModelRemote::GetValue(const std::vector<const Word*> &contextFactor, State* finalState) const
{
LMResult ret;
ret.unknown = false;
size_t count = contextFactor.size();
if (count == 0) {
if (finalState) *finalState = NULL;
ret.score = 0.0;
return ret;
}
//std::cerr << "contextFactor.size() = " << count << "\n";
size_t max = m_nGramOrder;
const FactorType factor = GetFactorType();
if (max > count) max = count;
Cache* cur = &m_cache;
int pc = static_cast<int>(count) - 1;
for (int i = 0; i < pc; ++i) {
const Factor* f = contextFactor[i]->GetFactor(factor);
cur = &cur->tree[f ? f : BOS];
}
const Factor* event_word = contextFactor[pc]->GetFactor(factor);
cur = &cur->tree[event_word ? event_word : EOS];
if (cur->prob) {
if (finalState) *finalState = cur->boState;
ret.score = cur->prob;
return ret;
}
cur->boState = *reinterpret_cast<const State*>(&m_curId);
++m_curId;
std::ostringstream os;
os << "prob ";
if (event_word == NULL) {
os << "</s>";
} else {
os << event_word->GetString();
}
for (size_t i=1; i<max; i++) {
const Factor* f = contextFactor[count-1-i]->GetFactor(factor);
if (f == NULL) {
os << " <s>";
} else {
os << ' ' << f->GetString();
}
}
os << std::endl;
std::string out = os.str();
write(sock, out.c_str(), out.size());
char res[6];
int r = read(sock, res, 6);
int errors = 0;
int cnt = 0;
while (1) {
if (r < 0) {
errors++;
sleep(1);
//std::cerr << "Error: read()\n";
if (errors > 5) exit(1);
} else if (r==0 || res[cnt] == '\n') {
break;
} else {
cnt += r;
if (cnt==6) break;
read(sock, &res[cnt], 6-cnt);
}
}
cur->prob = FloorScore(TransformLMScore(*reinterpret_cast<float*>(res)));
if (finalState) {
*finalState = cur->boState;
}
ret.score = cur->prob;
return ret;
}
LanguageModelRemote::~LanguageModelRemote()
{
// Step 8 When finished send all lingering transmissions and close the connection
close(sock);
}
}