fix possible link problem

1 files changed, 515 insertions, 0 deletions

diff --git a/training/utils/sentserver.cc b/training/utils/sentserver.cc
new file mode 100644
index 00000000..b425955f
--- /dev/null
+++ b/training/utils/sentserver.cc
@@ -0,0 +1,515 @@
+/* Copyright (c) 2001 by David Chiang. All rights reserved.*/
+
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <sched.h>
+#include <pthread.h>
+#include <errno.h>
+
+#include "sentserver.h"
+
+#define MAX_CLIENTS 64
+
+struct clientinfo {
+  int s;
+  struct sockaddr_in sin;
+};
+
+struct line {
+  int id;
+  char *s;
+  int status;
+  struct line *next;
+} *head, **ptail;
+
+int n_sent = 0, n_received=0, n_flushed=0;
+
+#define STATUS_RUNNING 0
+#define STATUS_ABORTED 1
+#define STATUS_FINISHED 2
+
+pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t clients_mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t input_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+int n_clients = 0;
+int s;
+int expect_multiline_output = 0;
+int log_mutex = 0;
+int stay_alive = 0;		/* dont panic and die with zero clients */
+
+void queue_finish(struct line *node, char *s, int fid);
+char * read_line(int fd, int multiline);
+void done (int code);
+
+struct line * queue_get(int fid) {
+	struct line *cur;
+	char *s, *synch;
+
+	if (log_mutex) fprintf(stderr, "Getting for data for fid %d\n", fid);
+	if (log_mutex) fprintf(stderr, "Locking queue mutex (%d)\n", fid);
+	pthread_mutex_lock(&queue_mutex);
+
+	/* First, check for aborted sentences. */
+
+	if (log_mutex) fprintf(stderr, "  Checking queue for aborted jobs (fid %d)\n", fid);
+	for (cur = head; cur != NULL; cur = cur->next) {
+		if (cur->status == STATUS_ABORTED) {
+			cur->status = STATUS_RUNNING;
+
+			if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+			pthread_mutex_unlock(&queue_mutex);
+
+			return cur;
+		}
+	}
+	if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+	pthread_mutex_unlock(&queue_mutex);
+
+	/* Otherwise, read a new one. */
+	if (log_mutex) fprintf(stderr, "Locking input mutex (%d)\n", fid);
+	if (log_mutex) fprintf(stderr, "  Reading input for new data (fid %d)\n", fid);
+	pthread_mutex_lock(&input_mutex);
+	s = read_line(0,0);
+
+	while (s) {
+		if (log_mutex) fprintf(stderr, "Locking queue mutex (%d)\n", fid);
+		pthread_mutex_lock(&queue_mutex);
+		if (log_mutex) fprintf(stderr, "Unlocking input mutex (%d)\n", fid);
+		pthread_mutex_unlock(&input_mutex);
+
+		cur = (line*)malloc(sizeof (struct line));
+		cur->id = n_sent;
+		cur->s = s;
+		cur->next = NULL;
+
+		*ptail = cur;
+		ptail = &cur->next;
+
+		n_sent++;
+
+		if (strcmp(s,"===SYNCH===\n")==0){
+			fprintf(stderr, "Received ===SYNCH=== signal (fid %d)\n", fid);
+			// Note: queue_finish calls free(cur->s).
+			// Therefore we need to create a new string here.
+			synch = (char*)malloc((strlen("===SYNCH===\n")+2) * sizeof (char));
+			synch = strcpy(synch, s);
+
+			if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+			pthread_mutex_unlock(&queue_mutex);
+			queue_finish(cur, synch, fid); /* handles its own lock */
+
+			if (log_mutex) fprintf(stderr, "Locking input mutex (%d)\n", fid);
+			if (log_mutex) fprintf(stderr, "  Reading input for new data (fid %d)\n", fid);
+			pthread_mutex_lock(&input_mutex);
+
+			s = read_line(0,0);
+		} else {
+			if (log_mutex) fprintf(stderr, "  Received new data %d (fid %d)\n", cur->id, fid);
+			cur->status = STATUS_RUNNING;
+			if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+			pthread_mutex_unlock(&queue_mutex);
+			return cur;
+		}
+	}
+
+	if (log_mutex) fprintf(stderr, "Unlocking input mutex (%d)\n", fid);
+	pthread_mutex_unlock(&input_mutex);
+	/* Only way to reach this point: no more output */
+
+	if (log_mutex) fprintf(stderr, "Locking queue mutex (%d)\n", fid);
+	pthread_mutex_lock(&queue_mutex);
+	if (head == NULL) {
+		fprintf(stderr, "Reached end of file. Exiting.\n");
+		done(0);
+	} else
+		ptail = NULL; /* This serves as a signal that there is no more input */
+	if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+	pthread_mutex_unlock(&queue_mutex);
+
+	return NULL;
+}
+
+void queue_panic() {
+	struct line *next;
+	while (head && head->status == STATUS_FINISHED) {
+		/* Write out finished sentences */
+		if (head->status == STATUS_FINISHED) {
+			fputs(head->s, stdout);
+			fflush(stdout);
+		}
+		/* Write out blank line for unfinished sentences */
+		if (head->status == STATUS_ABORTED) {
+			fputs("\n", stdout);
+			fflush(stdout);
+		}
+		/* By defition, there cannot be any RUNNING sentences, since
+		function is only called when n_clients == 0 */
+		free(head->s);
+		next = head->next;
+		free(head);
+		head = next;
+		n_flushed++;
+	}
+	fclose(stdout);
+	fprintf(stderr, "All clients died. Panicking, flushing completed sentences and exiting.\n");
+	done(1);
+}
+
+void queue_abort(struct line *node, int fid) {
+	if (log_mutex) fprintf(stderr, "Locking queue mutex (%d)\n", fid);
+	pthread_mutex_lock(&queue_mutex);
+	node->status = STATUS_ABORTED;
+	if (n_clients == 0) {
+		if (stay_alive) {
+			fprintf(stderr, "Warning! No live clients detected! Staying alive, will retry soon.\n");
+		} else {
+			queue_panic();
+		}
+	}
+	if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+	pthread_mutex_unlock(&queue_mutex);
+}
+
+
+void queue_print() {
+  struct line *cur;
+
+  fprintf(stderr, "  Queue\n");
+
+  for (cur = head; cur != NULL; cur = cur->next) {
+    switch(cur->status) {
+    case STATUS_RUNNING:
+      fprintf(stderr, "    %d running  ", cur->id); break;
+    case STATUS_ABORTED:
+      fprintf(stderr, "    %d aborted  ", cur->id); break;
+    case STATUS_FINISHED:
+      fprintf(stderr, "    %d finished ", cur->id); break;
+
+    }
+	fprintf(stderr, "\n");
+    //fprintf(stderr, cur->s);
+  }
+}
+
+void queue_finish(struct line *node, char *s, int fid) {
+  struct line *next;
+  if (log_mutex) fprintf(stderr, "Locking queue mutex (%d)\n", fid);
+  pthread_mutex_lock(&queue_mutex);
+
+  free(node->s);
+  node->s = s;
+  node->status = STATUS_FINISHED;
+  n_received++;
+
+  /* Flush out finished nodes */
+  while (head && head->status == STATUS_FINISHED) {
+
+    if (log_mutex) fprintf(stderr, "  Flushing finished node %d\n", head->id);
+
+    fputs(head->s, stdout);
+    fflush(stdout);
+    if (log_mutex) fprintf(stderr, "  Flushed node %d\n", head->id);
+    free(head->s);
+
+    next = head->next;
+    free(head);
+
+    head = next;
+
+    n_flushed++;
+
+    if (head == NULL) { /* empty queue */
+      if (ptail == NULL) { /* This can only happen if set in queue_get as signal that there is no more input. */
+        fprintf(stderr, "All sentences finished. Exiting.\n");
+        done(0);
+      } else /* ptail pointed at something which was just popped off the stack -- reset to head*/
+        ptail = &head;
+    }
+  }
+
+  if (log_mutex) fprintf(stderr, "  Flushing output %d\n", head->id);
+  fflush(stdout);
+  fprintf(stderr, "%d sentences sent, %d sentences finished, %d sentences flushed\n", n_sent, n_received, n_flushed);
+
+  if (log_mutex) fprintf(stderr, "Unlocking queue mutex (%d)\n", fid);
+  pthread_mutex_unlock(&queue_mutex);
+
+}
+
+char * read_line(int fd, int multiline) {
+  int size = 80;
+  char errorbuf[100];
+  char *s = (char*)malloc(size+2);
+  int result, errors=0;
+  int i = 0;
+
+  result = read(fd, s+i, 1);
+
+  while (1) {
+    if (result < 0) {
+      perror("read()");
+      sprintf(errorbuf, "Error code: %d\n", errno);
+      fputs(errorbuf, stderr);
+      errors++;
+      if (errors > 5) {
+	free(s);
+	return NULL;
+      } else {
+	sleep(1); /* retry after delay */
+      }
+    } else if (result == 0) {
+      break;
+    } else if (multiline==0 && s[i] == '\n') {
+      break;
+    } else {
+      if (s[i] == '\n'){
+	/* if we've reached this point,
+	   then multiline must be 1, and we're
+	   going to poll the fd for an additional
+	   line of data.  The basic design is to
+	   run a select on the filedescriptor fd.
+	   Select will return under two conditions:
+	   if there is data on the fd, or if a
+	   timeout is reached.  We'll select on this
+	   fd.  If select returns because there's data
+	   ready, keep going; else assume there's no
+	   more and return the data we already have.
+	*/
+
+	fd_set set;
+	FD_ZERO(&set);
+	FD_SET(fd, &set);
+
+	struct timeval timeout;
+	timeout.tv_sec = 3; // number of seconds for timeout
+	timeout.tv_usec = 0;
+
+	int ready = select(FD_SETSIZE, &set, NULL, NULL, &timeout);
+	if (ready<1){
+	  break; // no more data, stop looping
+	}
+      }
+      i++;
+
+      if (i == size) {
+	size = size*2;
+	s = (char*)realloc(s, size+2);
+      }
+    }
+
+    result = read(fd, s+i, 1);
+  }
+
+  if (result == 0 && i == 0) { /* end of file */
+    free(s);
+    return NULL;
+  }
+
+  s[i] = '\n';
+  s[i+1] = '\0';
+
+  return s;
+}
+
+void * new_client(void *arg) {
+  struct clientinfo *client = (struct clientinfo *)arg;
+  struct line *cur;
+  int result;
+  char *s;
+  char errorbuf[100];
+
+  pthread_mutex_lock(&clients_mutex);
+  n_clients++;
+  pthread_mutex_unlock(&clients_mutex);
+
+  fprintf(stderr, "Client connected (%d connected)\n", n_clients);
+
+  for (;;) {
+
+    cur = queue_get(client->s);
+
+    if (cur) {
+      /* fprintf(stderr, "Sending to client: %s", cur->s); */
+      fprintf(stderr, "Sending data %d to client (fid %d)\n", cur->id, client->s);
+      result = write(client->s, cur->s, strlen(cur->s));
+      if (result < strlen(cur->s)){
+        perror("write()");
+        sprintf(errorbuf, "Error code: %d\n", errno);
+        fputs(errorbuf, stderr);
+
+        pthread_mutex_lock(&clients_mutex);
+        n_clients--;
+        pthread_mutex_unlock(&clients_mutex);
+
+        fprintf(stderr, "Client died (%d connected)\n", n_clients);
+        queue_abort(cur, client->s);
+
+        close(client->s);
+        free(client);
+
+        pthread_exit(NULL);
+      }
+    } else {
+      close(client->s);
+      pthread_mutex_lock(&clients_mutex);
+      n_clients--;
+      pthread_mutex_unlock(&clients_mutex);
+      fprintf(stderr, "Client dismissed (%d connected)\n", n_clients);
+      pthread_exit(NULL);
+    }
+
+    s = read_line(client->s,expect_multiline_output);
+    if (s) {
+      /* fprintf(stderr, "Client (fid %d) returned: %s", client->s, s); */
+      fprintf(stderr, "Client (fid %d) returned data %d\n", client->s, cur->id);
+//      queue_print();
+      queue_finish(cur, s, client->s);
+    } else {
+      pthread_mutex_lock(&clients_mutex);
+      n_clients--;
+      pthread_mutex_unlock(&clients_mutex);
+
+      fprintf(stderr, "Client died (%d connected)\n", n_clients);
+      queue_abort(cur, client->s);
+
+      close(client->s);
+      free(client);
+
+      pthread_exit(NULL);
+    }
+
+  }
+  return 0;
+}
+
+void done (int code) {
+  close(s);
+  exit(code);
+}
+
+
+
+int main (int argc, char *argv[]) {
+  struct sockaddr_in sin, from;
+  int g;
+  socklen_t len;
+  struct clientinfo *client;
+  int port;
+  int opt;
+  int errors = 0;
+  int argi;
+  char *key = NULL, *client_key;
+  int use_key = 0;
+  /* the key stuff here doesn't provide any
+  real measure of security, it's mainly to keep
+  jobs from bumping into each other.  */
+
+  pthread_t tid;
+  port = DEFAULT_PORT;
+
+  for (argi=1; argi < argc; argi++){
+    if (strcmp(argv[argi], "-m")==0){
+      expect_multiline_output = 1;
+    } else if (strcmp(argv[argi], "-k")==0){
+      argi++;
+      if (argi == argc){
+      	fprintf(stderr, "Key must be specified after -k\n");
+      	exit(1);
+      }
+      key = argv[argi];
+      use_key = 1;
+    } else if (strcmp(argv[argi], "--stay-alive")==0){
+      stay_alive = 1;    /* dont panic and die with zero clients */
+    } else {
+      port = atoi(argv[argi]);
+    }
+  }
+
+  /* Initialize data structures */
+  head = NULL;
+  ptail = &head;
+
+  /* Set up listener */
+  s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+  opt = 1;
+  setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
+
+  sin.sin_family = AF_INET;
+  sin.sin_addr.s_addr = htonl(INADDR_ANY);
+  sin.sin_port = htons(port);
+  while (bind(s, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
+	perror("bind()");
+	sleep(1);
+	errors++;
+	if (errors > 100)
+	  exit(1);
+  }
+
+  len = sizeof(sin);
+  getsockname(s, (struct sockaddr *) &sin, &len);
+
+  fprintf(stderr, "Listening on port %hu\n", ntohs(sin.sin_port));
+
+  while (listen(s, MAX_CLIENTS) < 0) {
+	perror("listen()");
+	sleep(1);
+	errors++;
+	if (errors > 100)
+	  exit(1);
+  }
+
+  for (;;) {
+    len = sizeof(from);
+    g = accept(s, (struct sockaddr *)&from, &len);
+    if (g < 0) {
+      perror("accept()");
+      sleep(1);
+      continue;
+    }
+    client = (clientinfo*)malloc(sizeof(struct clientinfo));
+    client->s = g;
+    bcopy(&from, &client->sin, len);
+
+	if (use_key){
+		fd_set set;
+		FD_ZERO(&set);
+		FD_SET(client->s, &set);
+
+		struct timeval timeout;
+		timeout.tv_sec = 3; // number of seconds for timeout
+		timeout.tv_usec = 0;
+
+		int ready = select(FD_SETSIZE, &set, NULL, NULL, &timeout);
+		if (ready<1){
+			fprintf(stderr, "Prospective client failed to respond with correct key.\n");
+			close(client->s);
+			free(client);
+		} else {
+			client_key = read_line(client->s,0);
+			client_key[strlen(client_key)-1]='\0'; /* chop trailing newline */
+			if (strcmp(key, client_key)==0){
+				pthread_create(&tid, NULL, new_client, client);
+			} else {
+				fprintf(stderr, "Prospective client failed to respond with correct key.\n");
+				close(client->s);
+				free(client);
+			}
+			free(client_key);
+		}
+	} else {
+		pthread_create(&tid, NULL, new_client, client);
+	}
+  }
+
+}
+
+
+