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00018 #ifndef _PASSENGER_MESSAGE_CHANNEL_H_
00019 #define _PASSENGER_MESSAGE_CHANNEL_H_
00020
00021 #include <algorithm>
00022 #include <string>
00023 #include <list>
00024 #include <vector>
00025
00026 #include <sys/types.h>
00027 #include <sys/socket.h>
00028 #include <arpa/inet.h>
00029 #include <errno.h>
00030 #include <unistd.h>
00031 #include <cstdarg>
00032
00033 #include "Exceptions.h"
00034 #include "Utils.h"
00035
00036 namespace Passenger {
00037
00038 using namespace std;
00039
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00094
00095 class MessageChannel {
00096 private:
00097 const static char DELIMITER = '\0';
00098 int fd;
00099
00100 public:
00101
00102
00103
00104
00105
00106
00107 MessageChannel() {
00108 this->fd = -1;
00109 }
00110
00111
00112
00113
00114 MessageChannel(int fd) {
00115 this->fd = fd;
00116 }
00117
00118
00119
00120
00121
00122 void close() {
00123 if (fd != -1) {
00124 ::close(fd);
00125 fd = -1;
00126 }
00127 }
00128
00129
00130
00131
00132
00133
00134
00135
00136
00137
00138 void write(const list<string> &args) {
00139 list<string>::const_iterator it;
00140 string data;
00141 uint16_t dataSize = 0;
00142
00143 for (it = args.begin(); it != args.end(); it++) {
00144 dataSize += it->size() + 1;
00145 }
00146 data.reserve(dataSize + sizeof(dataSize));
00147 dataSize = htons(dataSize);
00148 data.append((const char *) &dataSize, sizeof(dataSize));
00149 for (it = args.begin(); it != args.end(); it++) {
00150 data.append(*it);
00151 data.append(1, DELIMITER);
00152 }
00153
00154 writeRaw(data);
00155 }
00156
00157
00158
00159
00160
00161
00162
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00164
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00166
00167
00168 void write(const char *name, ...) {
00169 list<string> args;
00170 args.push_back(name);
00171
00172 va_list ap;
00173 va_start(ap, name);
00174 while (true) {
00175 const char *arg = va_arg(ap, const char *);
00176 if (arg == NULL) {
00177 break;
00178 } else {
00179 args.push_back(arg);
00180 }
00181 }
00182 va_end(ap);
00183 write(args);
00184 }
00185
00186
00187
00188
00189
00190
00191
00192
00193 void writeScalar(const string &str) {
00194 writeScalar(str.c_str(), str.size());
00195 }
00196
00197
00198
00199
00200
00201
00202
00203
00204
00205
00206 void writeScalar(const char *data, unsigned int size) {
00207 uint32_t l = htonl(size);
00208 writeRaw((const char *) &l, sizeof(uint32_t));
00209 writeRaw(data, size);
00210 }
00211
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00214
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00217
00218
00219
00220
00221
00222 void writeRaw(const char *data, unsigned int size) {
00223 ssize_t ret;
00224 unsigned int written = 0;
00225 do {
00226 do {
00227 ret = ::write(fd, data + written, size - written);
00228 } while (ret == -1 && errno == EINTR);
00229 if (ret == -1) {
00230 throw SystemException("write() failed", errno);
00231 } else {
00232 written += ret;
00233 }
00234 } while (written < size);
00235 }
00236
00237
00238
00239
00240
00241
00242
00243
00244
00245 void writeRaw(const string &data) {
00246 writeRaw(data.c_str(), data.size());
00247 }
00248
00249
00250
00251
00252
00253
00254
00255
00256
00257
00258 void writeFileDescriptor(int fileDescriptor) {
00259 struct msghdr msg;
00260 struct iovec vec[1];
00261 char buf[1];
00262 struct {
00263 struct cmsghdr hdr;
00264 int fd;
00265 } cmsg;
00266
00267 msg.msg_name = NULL;
00268 msg.msg_namelen = 0;
00269
00270
00271 buf[0] = '\0';
00272 vec[0].iov_base = buf;
00273 vec[0].iov_len = 1;
00274 msg.msg_iov = vec;
00275 msg.msg_iovlen = 1;
00276
00277 msg.msg_control = (caddr_t)&cmsg;
00278 msg.msg_controllen = CMSG_SPACE(sizeof(int));
00279 msg.msg_flags = 0;
00280 cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
00281 cmsg.hdr.cmsg_level = SOL_SOCKET;
00282 cmsg.hdr.cmsg_type = SCM_RIGHTS;
00283 cmsg.fd = fileDescriptor;
00284
00285 if (sendmsg(fd, &msg, 0) == -1) {
00286 throw SystemException("Cannot send file descriptor with sendmsg()", errno);
00287 }
00288 }
00289
00290
00291
00292
00293
00294
00295
00296
00297
00298
00299 bool read(vector<string> &args) {
00300 uint16_t size;
00301 int ret;
00302 unsigned int alreadyRead = 0;
00303
00304 do {
00305 do {
00306 ret = ::read(fd, (char *) &size + alreadyRead, sizeof(size) - alreadyRead);
00307 } while (ret == -1 && errno == EINTR);
00308 if (ret == -1) {
00309 throw SystemException("read() failed", errno);
00310 } else if (ret == 0) {
00311 return false;
00312 }
00313 alreadyRead += ret;
00314 } while (alreadyRead < sizeof(size));
00315 size = ntohs(size);
00316
00317 string buffer;
00318 args.clear();
00319 buffer.reserve(size);
00320 while (buffer.size() < size) {
00321 char tmp[1024 * 8];
00322 do {
00323 ret = ::read(fd, tmp, min(size - buffer.size(), sizeof(tmp)));
00324 } while (ret == -1 && errno == EINTR);
00325 if (ret == -1) {
00326 throw SystemException("read() failed", errno);
00327 } else if (ret == 0) {
00328 return false;
00329 }
00330 buffer.append(tmp, ret);
00331 }
00332
00333 if (!buffer.empty()) {
00334 string::size_type start = 0, pos;
00335 const string &const_buffer(buffer);
00336 while ((pos = const_buffer.find('\0', start)) != string::npos) {
00337 args.push_back(const_buffer.substr(start, pos - start));
00338 start = pos + 1;
00339 }
00340 }
00341 return true;
00342 }
00343
00344
00345
00346
00347
00348
00349
00350
00351
00352 bool readScalar(string &output) {
00353 uint32_t size;
00354 unsigned int remaining;
00355
00356 if (!readRaw(&size, sizeof(uint32_t))) {
00357 return false;
00358 }
00359 size = ntohl(size);
00360
00361 output.clear();
00362 output.reserve(size);
00363 remaining = size;
00364 while (remaining > 0) {
00365 char buf[1024 * 32];
00366 unsigned int blockSize = min((unsigned int) sizeof(buf), remaining);
00367
00368 if (!readRaw(buf, blockSize)) {
00369 return false;
00370 }
00371 output.append(buf, blockSize);
00372 remaining -= blockSize;
00373 }
00374 return true;
00375 }
00376
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00390
00391
00392 bool readRaw(void *buf, unsigned int size) {
00393 ssize_t ret;
00394 unsigned int alreadyRead = 0;
00395
00396 while (alreadyRead < size) {
00397 do {
00398 ret = ::read(fd, (char *) buf + alreadyRead, size - alreadyRead);
00399 } while (ret == -1 && errno == EINTR);
00400 if (ret == -1) {
00401 throw SystemException("read() failed", errno);
00402 } else if (ret == 0) {
00403 return false;
00404 } else {
00405 alreadyRead += ret;
00406 }
00407 }
00408 return true;
00409 }
00410
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00419
00420
00421
00422 int readFileDescriptor() {
00423 struct msghdr msg;
00424 struct iovec vec[2];
00425 char buf[1];
00426 struct {
00427 struct cmsghdr hdr;
00428 int fd;
00429 } cmsg;
00430
00431 msg.msg_name = NULL;
00432 msg.msg_namelen = 0;
00433
00434 vec[0].iov_base = buf;
00435 vec[0].iov_len = sizeof(buf);
00436 msg.msg_iov = vec;
00437 msg.msg_iovlen = 1;
00438
00439 msg.msg_control = (caddr_t)&cmsg;
00440 msg.msg_controllen = CMSG_SPACE(sizeof(int));
00441 msg.msg_flags = 0;
00442 cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
00443 cmsg.hdr.cmsg_level = SOL_SOCKET;
00444 cmsg.hdr.cmsg_type = SCM_RIGHTS;
00445 cmsg.fd = -1;
00446
00447 if (recvmsg(fd, &msg, 0) == -1) {
00448 throw SystemException("Cannot read file descriptor with recvmsg()", errno);
00449 }
00450
00451 if (msg.msg_controllen != CMSG_SPACE(sizeof(int))
00452 || cmsg.hdr.cmsg_len != CMSG_SPACE(0) + sizeof(int)
00453 || cmsg.hdr.cmsg_level != SOL_SOCKET
00454 || cmsg.hdr.cmsg_type != SCM_RIGHTS) {
00455 throw IOException("No valid file descriptor received.");
00456 }
00457 return cmsg.fd;
00458 }
00459 };
00460
00461 }
00462
00463 #endif