X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/768d7355deef8b14f6d2d5bdc9bc8d5f01d2d0aa..f9635e06947ec6bc61c7977e7a3f9dba2c43d784:/server/server.c

diff --git a/server/server.c b/server/server.c
index 5a11b8c..64502c0 100644
--- a/server/server.c
+++ b/server/server.c
@@ -63,6 +63,7 @@
 #include "eventlog.h"
 #include "defs.h"
 #include "cache.h"
+#include "unicode.h"
 
 #ifndef NONCE_SIZE
 # define NONCE_SIZE 16
@@ -81,22 +82,35 @@ struct listener {
   int pf;
 };
 
+/** @brief One client connection */
 struct conn {
+  /** @brief Read commands from here */
   ev_reader *r;
+  /** @brief Send responses to here */
   ev_writer *w;
+  /** @brief Underlying file descriptor */
   int fd;
+  /** @brief Unique identifier for connection used in log messages */
   unsigned tag;
+  /** @brief Login name or NULL */
   char *who;
+  /** @brief Event loop */
   ev_source *ev;
+  /** @brief Nonce chosen for this connection */
   unsigned char nonce[NONCE_SIZE];
+  /** @brief Current reader callback
+   *
+   * We change this depending on whether we're servicing the @b log command
+   */
   ev_reader_callback *reader;
+  /** @brief Event log output sending to this connection */
   struct eventlog_output *lo;
+  /** @brief Parent listener */
   const struct listener *l;
 };
 
 static int reader_callback(ev_source *ev,
 			   ev_reader *reader,
-			   int fd,
 			   void *ptr,
 			   size_t bytes,
 			   int eof,
@@ -104,49 +118,54 @@ static int reader_callback(ev_source *ev,
 
 static const char *noyes[] = { "no", "yes" };
 
+/** @brief Called when a connection's writer fails or is shut down
+ *
+ * If the connection still has a raeder that is cancelled.
+ */
 static int writer_error(ev_source attribute((unused)) *ev,
-			int fd,
 			int errno_value,
 			void *u) {
   struct conn *c = u;
 
-  D(("server writer_error %d %d", fd, errno_value));
+  D(("server writer_error S%x %d", c->tag, errno_value));
   if(errno_value == 0) {
     /* writer is done */
-    c->w = 0;
-    if(c->r == 0) {
-      D(("server writer_error closes %d", fd));
-      xclose(fd);		/* reader is done too, close */
-    } else {
-      D(("server writer_error shutdown %d SHUT_WR", fd));
-      xshutdown(fd, SHUT_WR);	/* reader is not done yet */
-    }
+    D(("S%x writer completed", c->tag));
   } else {
     if(errno_value != EPIPE)
       error(errno_value, "S%x write error on socket", c->tag);
-    if(c->r)
+    if(c->r) {
+      D(("cancel reader"));
       ev_reader_cancel(c->r);
-    xclose(fd);
+      c->r = 0;
+    }
+    D(("done cancel reader"));
   }
+  c->w = 0;
+  ev_report(ev);
   return 0;
 }
 
+/** @brief Called when a conncetion's reader fails or is shut down
+ *
+ * If connection still has a writer then it is closed.
+ */
 static int reader_error(ev_source attribute((unused)) *ev,
-			int fd,
 			int errno_value,
 			void *u) {
   struct conn *c = u;
 
-  D(("server reader_error %d %d", fd, errno_value));
-  error(errno, "S%x read error on socket", c->tag);
-  ev_writer_cancel(c->w);
+  D(("server reader_error S%x %d", c->tag, errno_value));
+  error(errno_value, "S%x read error on socket", c->tag);
+  if(c->w)
+    ev_writer_close(c->w);
+  c->w = 0;
+  c->r = 0;
   ev_report(ev);
-  info("closing fd %d", fd);
-  xclose(fd);
   return 0;
 }
 
-/* return true if we are talking to a trusted user */
+/** @brief Return true if we are talking to a trusted user */
 static int trusted(struct conn *c) {
   int n;
   
@@ -665,21 +684,19 @@ static int c_random_enabled(struct conn *c,
   return 1;			/* completed */
 }
 
+static void got_stats(char *stats, void *u) {
+  struct conn *const c = u;
+
+  sink_printf(ev_writer_sink(c->w), "253 stats\n%s\n.\n", stats);
+  /* Now we can start processing commands again */
+  ev_reader_enable(c->r);
+}
+
 static int c_stats(struct conn *c,
 		   char attribute((unused)) **vec,
 		   int attribute((unused)) nvec) {
-  char **v;
-  int nv, n;
-
-  v = trackdb_stats(&nv);
-  sink_printf(ev_writer_sink(c->w), "253 stats\n");
-  for(n = 0; n < nv; ++n) {
-    if(v[n][0] == '.')
-      sink_writes(ev_writer_sink(c->w), ".");
-    sink_printf(ev_writer_sink(c->w), "%s\n", v[n]);
-  }
-  sink_writes(ev_writer_sink(c->w), ".\n");
-  return 1;
+  trackdb_stats_subprocess(c->ev, got_stats, c);
+  return 0;				/* not yet complete */
 }
 
 static int c_volume(struct conn *c,
@@ -719,29 +736,41 @@ static int c_volume(struct conn *c,
   return 1;
 }
 
-/* we are logging, and some data is available to read */
-static int logging_reader_callback(ev_source *ev,
+/** @brief Called when data arrives on a log connection
+ *
+ * We just discard all such data.  The client may occasionally send data as a
+ * keepalive.
+ */
+static int logging_reader_callback(ev_source attribute((unused)) *ev,
 				   ev_reader *reader,
-				   int fd,
-				   void *ptr,
+				   void attribute((unused)) *ptr,
 				   size_t bytes,
-				   int eof,
-				   void *u) {
+				   int attribute((unused)) eof,
+				   void attribute((unused)) *u) {
   struct conn *c = u;
 
-  /* don't log to this conn any more */
-  eventlog_remove(c->lo);
-  /* terminate the log output */
-  sink_writes(ev_writer_sink(c->w), ".\n");
-  /* restore the reader callback */
-  c->reader = reader_callback;
-  /* ...and exit via it */
-  return c->reader(ev, reader, fd, ptr, bytes, eof, u);
+  ev_reader_consume(reader, bytes);
+  if(eof) {
+    /* Oops, that's all for now */
+    D(("logging reader eof"));
+    if(c->w) {
+      D(("close writer"));
+      ev_writer_close(c->w);
+      c->w = 0;
+    }
+    c->r = 0;
+  }
+  return 0;
 }
 
 static void logclient(const char *msg, void *user) {
   struct conn *c = user;
 
+  if(!c->w || !c->r) {
+    /* This connection has gone up in smoke for some reason */
+    eventlog_remove(c->lo);
+    return;
+  }
   sink_printf(ev_writer_sink(c->w), "%"PRIxMAX" %s\n",
 	      (uintmax_t)time(0), msg);
 }
@@ -893,6 +922,10 @@ static int c_tags(struct conn *c,
 static int c_set_global(struct conn *c,
 			char **vec,
 			int attribute((unused)) nvec) {
+  if(vec[0][0] == '_') {
+    sink_writes(ev_writer_sink(c->w), "550 cannot set internal global preferences\n");
+    return 1;
+  }
   trackdb_set_global(vec[0], vec[1], c->who);
   sink_printf(ev_writer_sink(c->w), "250 OK\n");
   return 1;
@@ -1012,6 +1045,11 @@ static int command(struct conn *c, char *line) {
   int nvec, n;
 
   D(("server command %s", line));
+  /* We force everything into NFC as early as possible */
+  if(!(line = utf8_compose_canon(line, strlen(line), 0))) {
+    sink_writes(ev_writer_sink(c->w), "500 cannot normalize command\n");
+    return 1;
+  }
   if(!(vec = split(line, &nvec, SPLIT_QUOTES, command_error, c))) {
     sink_writes(ev_writer_sink(c->w), "500 cannot parse command\n");
     return 1;
@@ -1049,20 +1087,18 @@ static int command(struct conn *c, char *line) {
 /* redirect to the right reader callback for our current state */
 static int redirect_reader_callback(ev_source *ev,
 				    ev_reader *reader,
-				    int fd,
 				    void *ptr,
 				    size_t bytes,
 				    int eof,
 				    void *u) {
   struct conn *c = u;
 
-  return c->reader(ev, reader, fd, ptr, bytes, eof, u);
+  return c->reader(ev, reader, ptr, bytes, eof, u);
 }
 
 /* the main command reader */
 static int reader_callback(ev_source attribute((unused)) *ev,
 			   ev_reader *reader,
-			   int attribute((unused)) fd,
 			   void *ptr,
 			   size_t bytes,
 			   int eof,
@@ -1092,8 +1128,13 @@ static int reader_callback(ev_source attribute((unused)) *ev,
   if(eof) {
     if(bytes)
       error(0, "S%x unterminated line", c->tag);
+    D(("normal reader close"));
     c->r = 0;
-    return ev_writer_close(c->w);
+    if(c->w) {
+      D(("close associated writer"));
+      ev_writer_close(c->w);
+      c->w = 0;
+    }
   }
   return 0;
 }
@@ -1116,6 +1157,7 @@ static int listen_callback(ev_source *ev,
 		       "client writer");
   c->r = ev_reader_new(ev, fd, redirect_reader_callback, reader_error, c,
 		       "client reader");
+  ev_tie(c->r, c->w);
   c->fd = fd;
   c->reader = reader_callback;
   c->l = l;