X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/763d5e6ad88ef3ba1cd1d7742d060e4f1e54c6b8..ad58ebcc8a950f4624cfb1a836e18a703c3b6610:/lib/eclient.c

diff --git a/lib/eclient.c b/lib/eclient.c
index 971dc4c..43fafac 100644
--- a/lib/eclient.c
+++ b/lib/eclient.c
@@ -17,6 +17,9 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  * USA
  */
+/** @file lib/eclient.c
+ * @brief Client code for event-driven programs
+ */
 
 #include <config.h>
 #include "types.h"
@@ -57,16 +60,18 @@
 
 /* Types *********************************************************************/
 
+/** @brief Client state */
 enum client_state {
-  state_disconnected,                   /* not connected */
-  state_connecting,                     /* waiting for connect() */
-  state_connected,                      /* connected but not authenticated */
-  state_idle,                           /* not doing anything */
-  state_cmdresponse,                    /* waiting for command resonse */
-  state_body,                           /* accumulating body */
-  state_log,                            /* monitoring log */
+  state_disconnected,          /**< @brief not connected */
+  state_connecting,            /**< @brief waiting for connect() */
+  state_connected,             /**< @brief connected but not authenticated */
+  state_idle,                  /**< @brief not doing anything */
+  state_cmdresponse,           /**< @brief waiting for command resonse */
+  state_body,                  /**< @brief accumulating body */
+  state_log,                   /**< @brief monitoring log */
 };
 
+/** @brief Names for @ref client_state */
 static const char *const states[] = {
   "disconnected",
   "connecting",
@@ -79,42 +84,50 @@ static const char *const states[] = {
 
 struct operation;                       /* forward decl */
 
+/** @brief Type of an operation callback */
 typedef void operation_callback(disorder_eclient *c, struct operation *op);
 
-/* A pending operation.  This can be either a command or part of the
- * authentication protocol.  In the former case new commands are appended to
- * the list, in the latter case they are inserted at the front. */
+/** @brief A pending operation.
+ *
+ * This can be either a command or part of the authentication protocol.  In the
+ * former case new commands are appended to the list, in the latter case they
+ * are inserted at the front. */
 struct operation {
-  struct operation *next;               /* next operation */
-  char *cmd;                            /* command to send or 0 */
-  operation_callback *opcallback;       /* internal completion callback */
-  void (*completed)();                  /* user completion callback or 0 */
-  void *v;                              /* data for COMPLETED */
-  disorder_eclient *client;             /* owning client */
-  int sent;                             /* true if sent to server */
+  struct operation *next;          /**< @brief next operation */
+  char *cmd;                       /**< @brief command to send or 0 */
+  operation_callback *opcallback;  /**< @brief internal completion callback */
+  void (*completed)();             /**< @brief user completion callback or 0 */
+  void *v;                         /**< @brief data for COMPLETED */
+  disorder_eclient *client;        /**< @brief owning client */
+
+  /** @brief true if sent to server
+   *
+   * This is cleared by disorder_eclient_close(), forcing all queued
+   * commands to be transparently resent.
+   */
+  int sent;
 };
 
+/** @brief Client structure */
 struct disorder_eclient {
   const char *ident;
-  int fd;
-  enum client_state state;              /* current state */
-  int authenticated;                    /* true when authenicated */
-  struct dynstr output;                 /* output buffer */
-  struct dynstr input;                  /* input buffer */
-  int eof;                              /* input buffer is at EOF */
-  /* error reporting callbacks */
-  const disorder_eclient_callbacks *callbacks;
-  void *u;
-  /* operation queuue */
-  struct operation *ops, **opstail;
+  int fd;                               /**< @brief connection to server */
+  enum client_state state;              /**< @brief current state */
+  int authenticated;                    /**< @brief true when authenicated */
+  struct dynstr output;                 /**< @brief output buffer */
+  struct dynstr input;                  /**< @brief input buffer */
+  int eof;                              /**< @brief input buffer is at EOF */
+  const disorder_eclient_callbacks *callbacks; /**< @brief error callbacks */
+  void *u;                              /**< @brief user data */
+  struct operation *ops;                /**< @brief queue of operations */
+  struct operation **opstail;           /**< @brief queue tail */
   /* accumulated response */
-  int rc;                               /* response code */
-  char *line;                           /* complete line */
-  struct vector vec;                    /* body */
-  /* log client callback */
-  const disorder_eclient_log_callbacks *log_callbacks;
-  void *log_v;
-  unsigned long statebits;              /* current state */
+  int rc;                               /**< @brief response code */
+  char *line;                           /**< @brief complete line */
+  struct vector vec;                    /**< @brief body */
+  const disorder_eclient_log_callbacks *log_callbacks; /**< @brief log callbacks */
+  void *log_v;                          /**< @brief user data */
+  unsigned long statebits;              /**< @brief current state */
 };
 
 /* Forward declarations ******************************************************/
@@ -160,13 +173,18 @@ static void logentry_volume(disorder_eclient *c, int nvec, char **vec);
 
 /* Tables ********************************************************************/
 
-static const struct logentry_handler {
-  const char *name;
-  int min, max;
+/** @brief One possible log entry */
+struct logentry_handler {
+  const char *name;                     /**< @brief Entry name */
+  int min;                              /**< @brief Minimum arguments */
+  int max;                              /**< @brief Maximum arguments */
   void (*handler)(disorder_eclient *c,
                   int nvec,
-                  char **vec);
-} logentry_handlers[] = {
+                  char **vec);          /**< @brief Handler function */
+};
+
+/** @brief Table for parsing log entries */
+static const struct logentry_handler logentry_handlers[] = {
 #define LE(X, MIN, MAX) { #X, MIN, MAX, logentry_##X }
   LE(completed, 1, 1),
   LE(failed, 2, 2),
@@ -183,6 +201,10 @@ static const struct logentry_handler {
 
 /* Setup and teardown ********************************************************/
 
+/** @brief Create a new client
+ *
+ * Does NOT connect the client - connections are made (and re-made) on demand.
+ */
 disorder_eclient *disorder_eclient_new(const disorder_eclient_callbacks *cb,
                                        void *u) {
   disorder_eclient *c = xmalloc(sizeof *c);
@@ -194,9 +216,20 @@ disorder_eclient *disorder_eclient_new(const disorder_eclient_callbacks *cb,
   vector_init(&c->vec);
   dynstr_init(&c->input);
   dynstr_init(&c->output);
+  if(!config->password) {
+    error(0, "no password set");
+    return 0;
+  }
   return c;
 }
 
+/** @brief Disconnect a client
+ * @param c Client to disconnect
+ *
+ * NB that this routine just disconnnects the TCP connection.  It does not
+ * destroy the client!  If you continue to use it then it will attempt to
+ * reconnect.
+ */
 void disorder_eclient_close(disorder_eclient *c) {
   struct operation *op;
 
@@ -217,9 +250,34 @@ void disorder_eclient_close(disorder_eclient *c) {
     op->sent = 0;
 }
 
+/** @brief Return true if @c c is connected
+ *
+ * By connected it is meant that commands have a reasonable chance of being
+ * processed soon, not merely that a TCP connection exists - for instance if
+ * the client is still authenticating then that does not count as connected.
+ */
+int disorder_eclient_connected(const disorder_eclient *c) {
+  switch(c->state) {
+  case state_disconnected:
+  case state_connecting:
+  case state_connected:
+    return 0;
+  case state_idle:
+  case state_cmdresponse:
+  case state_body:
+  case state_log:
+    return 1;
+  }
+  assert(!"reached");
+}
+
 /* Error reporting ***********************************************************/
 
-/* called when a connection error occurs */
+/** @brief called when a connection error occurs
+ *
+ * After this called we will be disconnected (by disorder_eclient_close()),
+ * so there will be a reconnection before any commands can be sent.
+ */
 static int comms_error(disorder_eclient *c, const char *fmt, ...) {
   va_list ap;
   char *s;
@@ -233,7 +291,7 @@ static int comms_error(disorder_eclient *c, const char *fmt, ...) {
   return -1;
 }
 
-/* called when the server reports an error */
+/** @brief called when the server reports an error */
 static int protocol_error(disorder_eclient *c, struct operation *op,
                           int code, const char *fmt, ...) {
   va_list ap;
@@ -249,9 +307,18 @@ static int protocol_error(disorder_eclient *c, struct operation *op,
 
 /* State machine *************************************************************/
 
+/** @brief Called when there's something to do
+ * @param c Client
+ * @param mode bitmap of @ref DISORDER_POLL_READ and/or @ref DISORDER_POLL_WRITE.
+ *
+ * This should be called from by your code when the file descriptor is readable
+ * or writable (as requested by the @c poll callback, see @ref
+ * disorder_eclient_callbacks) and in any case from time to time (with @p mode
+ * = 0) to allow for retries to work.
+ */
 void disorder_eclient_polled(disorder_eclient *c, unsigned mode) {
   struct operation *op;
-
+  
   D(("disorder_eclient_polled fd=%d state=%s mode=[%s %s]",
      c->fd, states[c->state],
      mode & DISORDER_POLL_READ ? "READ" : "",
@@ -381,7 +448,7 @@ void disorder_eclient_polled(disorder_eclient *c, unsigned mode) {
   if(c->fd != -1) c->callbacks->poll(c->u, c, c->fd, mode);
 }
 
-/* Called to start connecting */
+/** @brief Called to start connecting */
 static int start_connect(void *cc,
 			 const struct sockaddr *sa,
 			 socklen_t len,
@@ -415,7 +482,7 @@ static int start_connect(void *cc,
   return 0;
 }
 
-/* Called when maybe connected */
+/** @brief Called when poll triggers while waiting for a connection */
 static void maybe_connected(disorder_eclient *c) {
   /* We either connected, or got an error. */
   int err;
@@ -546,8 +613,10 @@ static void read_input(disorder_eclient *c) {
     if(c->state > state_connecting)
       consume(&c->input, (nl - c->input.vec) + 1);
   }
-  if(c->eof)
+  if(c->eof) {
     comms_error(c, "reading from %s: server disconnected", c->ident);
+    c->authenticated = 0;
+  }
 }
 
 /* called with a line that has just been read */