diff mbox

add file desc to gdbserver client_state

Message ID d30fd2c3-c26e-92e1-8ed6-3a2a2897d3fe@redhat.com
State New
Headers show

Commit Message

Stan Cox Feb. 6, 2020, 7:41 p.m. UTC
This patch adds struct multi_client_states for managing multiple clients
and adds gdb_fildes_t support to routines write_prim, read_prim, readchar
for handling client specific io,with each client associated with its
corresponding file desc.   Thispatch adds the corresponding file desc to
the client_state and adds afile desc parameter to the gdbserver I/O ops.
It also adds structmulti_client_states which currently just manages a 
primary
client_statebut will later allow managing  a collection of client_states
where each client_state is the state for an individualclient.  This patch
defines get_client_state using multi_client_statesdefines.  Concurrent with
this patch is an strace patch that adds a gdbserver backend to strace.

Add struct multi_client_states

* server.h (struct multi_client_states):  New.
* server.c (g_client_states)
   (get_client_states, multi_client_sates::add_client_state):  New.
   (captured_main):  Set multi_client_states.client_states
* remote-utils.c (gdb_connected, remote_prepare, remote_close)
   (putpkt_binary_1, getpkt)  Use client_state.remote_desc.
   (handle_accept_event):  Set the client state for this remote file  desc.
   (write_prim, read_prim, readchar): Add gdb_fildes_t parameter.
    Change all callers.
diff mbox

Patch

    Add struct multi_client_states
    
    * server.h (struct multi_client_states):  New.
    * server.c (g_client_states)
      (get_client_states, multi_client_sates::add_client_state):  New.
      (captured_main):  Set multi_client_states.client_states
    * remote-utils.c (gdb_connected, remote_prepare, remote_close)
      (putpkt_binary_1, getpkt)  Use client_state.remote_desc.
      (handle_accept_event):  Set the client state for this remote file desc.
      (write_prim, read_prim, readchar): Add gdb_fildes_t parameter.
      Change all callers.
---
 gdb/gdbserver/ChangeLog      | 12 ++++++++++++
 gdb/gdbserver/remote-utils.c | 78 +++++++++++++++++++++++++++++++++++++++++++++---------------------------------
 gdb/gdbserver/server.c       | 28 +++++++++++++++++++++++-----
 gdb/gdbserver/server.h       | 31 +++++++++++++++++++++++++++++--
 4 files changed, 109 insertions(+), 40 deletions(-)

diff --git a/gdb/gdbserver/remote-utils.c b/gdb/gdbserver/remote-utils.c
index b8a8c6576f9..63d3cad9597 100644
--- a/gdb/gdbserver/remote-utils.c
+++ b/gdb/gdbserver/remote-utils.c
@@ -94,7 +94,7 @@  enum {
    Either NOT_SCHEDULED or the callback id.  */
 static int readchar_callback = NOT_SCHEDULED;
 
-static int readchar (void);
+static int readchar (gdb_fildes_t);
 static void reset_readchar (void);
 static void reschedule (void);
 
@@ -108,7 +108,6 @@  struct sym_cache
 
 static int remote_is_stdio = 0;
 
-static gdb_fildes_t remote_desc = INVALID_DESCRIPTOR;
 static gdb_fildes_t listen_desc = INVALID_DESCRIPTOR;
 
 #ifdef USE_WIN32API
@@ -119,7 +118,8 @@  static gdb_fildes_t listen_desc = INVALID_DESCRIPTOR;
 int
 gdb_connected (void)
 {
-  return remote_desc != INVALID_DESCRIPTOR;
+  client_state &cs = get_client_state ();
+  return cs.remote_desc != INVALID_DESCRIPTOR;
 }
 
 /* Return true if the remote connection is over stdio.  */
@@ -149,6 +149,7 @@  handle_accept_event (int err, gdb_client_data client_data)
 {
   struct sockaddr_storage sockaddr;
   socklen_t len = sizeof (sockaddr);
+  gdb_fildes_t remote_desc;
 
   if (debug_threads)
     debug_printf ("handling possible accept event\n");
@@ -157,6 +158,8 @@  handle_accept_event (int err, gdb_client_data client_data)
   if (remote_desc == -1)
     perror_with_name ("Accept failed");
 
+  get_client_states ().add_client_state (remote_desc);
+
   /* Enable TCP keep alive process. */
   socklen_t tmp = 1;
   setsockopt (remote_desc, SOL_SOCKET, SO_KEEPALIVE,
@@ -269,6 +272,8 @@  remote_prepare (const char *name)
     }
 #endif
 
+  cs.remote_desc = INVALID_DESCRIPTOR;
+
   int r = getaddrinfo (parsed.host_str.c_str (), parsed.port_str.c_str (),
 		       &hint, &ainfo);
 
@@ -325,6 +330,7 @@  void
 remote_open (const char *name)
 {
   const char *port_str;
+  gdb_fildes_t remote_desc;
 
   port_str = strchr (name, ':');
 #ifdef USE_WIN32API
@@ -417,17 +423,19 @@  remote_open (const char *name)
 void
 remote_close (void)
 {
-  delete_file_handler (remote_desc);
+  client_state &cs = get_client_state ();
+
+  delete_file_handler (cs.remote_desc);
 
   disable_async_io ();
 
 #ifdef USE_WIN32API
-  closesocket (remote_desc);
+  closesocket (cs.remote_desc);
 #else
   if (! remote_connection_is_stdio ())
-    close (remote_desc);
+    close (cs.remote_desc);
 #endif
-  remote_desc = INVALID_DESCRIPTOR;
+  cs.remote_desc = INVALID_DESCRIPTOR;
 
   reset_readchar ();
 }
@@ -608,12 +616,12 @@  read_ptid (const char *buf, const char **obuf)
    This may return less than COUNT.  */
 
 static int
-write_prim (const void *buf, int count)
+write_prim (gdb_fildes_t fd, const void *buf, int count)
 {
   if (remote_connection_is_stdio ())
     return write (fileno (stdout), buf, count);
   else
-    return write (remote_desc, buf, count);
+    return write (fd, buf, count);
 }
 
 /* Read COUNT bytes from the client and store in BUF.
@@ -621,12 +629,12 @@  write_prim (const void *buf, int count)
    This may return less than COUNT.  */
 
 static int
-read_prim (void *buf, int count)
+read_prim (gdb_fildes_t fd, void *buf, int count)
 {
   if (remote_connection_is_stdio ())
     return read (fileno (stdin), buf, count);
   else
-    return read (remote_desc, buf, count);
+    return read (fd, buf, count);
 }
 
 /* Send a packet to the remote machine, with error checking.
@@ -667,7 +675,7 @@  putpkt_binary_1 (char *buf, int cnt, int is_notif)
 
   do
     {
-      if (write_prim (buf2, p - buf2) != p - buf2)
+      if (write_prim (cs.remote_desc, buf2, p - buf2) != p - buf2)
 	{
 	  perror ("putpkt(write)");
 	  free (buf2);
@@ -680,9 +688,9 @@  putpkt_binary_1 (char *buf, int cnt, int is_notif)
 	  if (remote_debug)
 	    {
 	      if (is_notif)
-		debug_printf ("putpkt (\"%s\"); [notif]\n", buf2);
+	  	debug_printf ("putpkt (%d, \"%s\"); [notif]\n", cs.remote_desc, buf2);
 	      else
-		debug_printf ("putpkt (\"%s\"); [noack mode]\n", buf2);
+		debug_printf ("putpkt (%d, \"%s\"); [noack mode]\n", cs.remote_desc, buf2);
 	      debug_flush ();
 	    }
 	  break;
@@ -690,11 +698,11 @@  putpkt_binary_1 (char *buf, int cnt, int is_notif)
 
       if (remote_debug)
 	{
-	  debug_printf ("putpkt (\"%s\"); [looking for ack]\n", buf2);
+	  debug_printf ("putpkt (%d, \"%s\"); [looking for ack]\n", cs.remote_desc, buf2);
 	  debug_flush ();
 	}
 
-      cc = readchar ();
+      cc = readchar (cs.remote_desc);
 
       if (cc < 0)
 	{
@@ -749,6 +757,7 @@  putpkt_notif (char *buf)
 static void
 input_interrupt (int unused)
 {
+  client_state &cs = get_client_state ();
   fd_set readset;
   struct timeval immediate = { 0, 0 };
 
@@ -756,13 +765,13 @@  input_interrupt (int unused)
      be a problem under NetBSD 1.4 and 1.5.  */
 
   FD_ZERO (&readset);
-  FD_SET (remote_desc, &readset);
-  if (select (remote_desc + 1, &readset, 0, 0, &immediate) > 0)
+  FD_SET (cs.remote_desc, &readset);
+  if (select (cs.remote_desc + 1, &readset, 0, 0, &immediate) > 0)
     {
       int cc;
       char c = 0;
 
-      cc = read_prim (&c, 1);
+      cc = read_prim (cs.remote_desc, &c, 1);
 
       if (cc == 0)
 	{
@@ -787,10 +796,11 @@  input_interrupt (int unused)
 void
 check_remote_input_interrupt_request (void)
 {
+  client_state &cs = get_client_state ();
   /* This function may be called before establishing communications,
      therefore we need to validate the remote descriptor.  */
 
-  if (remote_desc == INVALID_DESCRIPTOR)
+  if (cs.remote_desc == INVALID_DESCRIPTOR)
     return;
 
   input_interrupt (0);
@@ -816,6 +826,7 @@  block_unblock_async_io (int block)
 static void
 nto_comctrl (int enable)
 {
+  client_state &cs = get_client_state ();
   struct sigevent event;
 
   if (enable)
@@ -825,11 +836,11 @@  nto_comctrl (int enable)
       event.sigev_code = 0;
       event.sigev_value.sival_ptr = NULL;
       event.sigev_priority = -1;
-      ionotify (remote_desc, _NOTIFY_ACTION_POLLARM, _NOTIFY_COND_INPUT,
+      ionotify (cs.remote_desc, _NOTIFY_ACTION_POLLARM, _NOTIFY_COND_INPUT,
 		&event);
     }
   else
-    ionotify (remote_desc, _NOTIFY_ACTION_POLL, _NOTIFY_COND_INPUT, NULL);
+    ionotify (cs.remote_desc, _NOTIFY_ACTION_POLL, _NOTIFY_COND_INPUT, NULL);
 }
 #endif /* __QNX__ */
 
@@ -892,13 +903,13 @@  static unsigned char *readchar_bufp;
 /* Returns next char from remote GDB.  -1 if error.  */
 
 static int
-readchar (void)
+readchar (gdb_fildes_t fd)
 {
   int ch;
 
   if (readchar_bufcnt == 0)
     {
-      readchar_bufcnt = read_prim (readchar_buf, sizeof (readchar_buf));
+      readchar_bufcnt = read_prim (fd, readchar_buf, sizeof (readchar_buf));
 
       if (readchar_bufcnt <= 0)
 	{
@@ -973,6 +984,7 @@  getpkt (char *buf)
   char *bp;
   unsigned char csum, c1, c2;
   int c;
+  gdb_fildes_t fd = cs.remote_desc;
 
   while (1)
     {
@@ -980,7 +992,7 @@  getpkt (char *buf)
 
       while (1)
 	{
-	  c = readchar ();
+	  c = readchar (fd);
 
 	  /* The '\003' may appear before or after each packet, so
 	     check for an input interrupt.  */
@@ -1005,7 +1017,7 @@  getpkt (char *buf)
       bp = buf;
       while (1)
 	{
-	  c = readchar ();
+	  c = readchar (fd);
 	  if (c < 0)
 	    return -1;
 	  if (c == '#')
@@ -1015,8 +1027,8 @@  getpkt (char *buf)
 	}
       *bp = 0;
 
-      c1 = fromhex (readchar ());
-      c2 = fromhex (readchar ());
+      c1 = fromhex (readchar (fd));
+      c2 = fromhex (readchar (fd));
 
       if (csum == (c1 << 4) + c2)
 	break;
@@ -1033,7 +1045,7 @@  getpkt (char *buf)
 
       fprintf (stderr, "Bad checksum, sentsum=0x%x, csum=0x%x, buf=%s\n",
 	       (c1 << 4) + c2, csum, buf);
-      if (write_prim ("-", 1) != 1)
+      if (write_prim (fd, "-", 1) != 1)
 	return -1;
     }
 
@@ -1041,11 +1053,11 @@  getpkt (char *buf)
     {
       if (remote_debug)
 	{
-	  debug_printf ("getpkt (\"%s\");  [sending ack] \n", buf);
+	  debug_printf ("getpkt (%d, \"%s\");  [sending ack] \n", fd, buf);
 	  debug_flush ();
 	}
 
-      if (write_prim ("+", 1) != 1)
+      if (write_prim (fd, "+", 1) != 1)
 	return -1;
 
       if (remote_debug)
@@ -1058,7 +1070,7 @@  getpkt (char *buf)
     {
       if (remote_debug)
 	{
-	  debug_printf ("getpkt (\"%s\");  [no ack sent] \n", buf);
+	  debug_printf ("getpkt (%d, \"%s\");  [no ack sent] \n", fd, buf);
 	  debug_flush ();
 	}
     }
@@ -1075,7 +1087,7 @@  getpkt (char *buf)
   while (readchar_bufcnt > 0 && *readchar_bufp == '\003')
     {
       /* Consume the interrupt character in the buffer.  */
-      readchar ();
+      readchar (fd);
       (*the_target->request_interrupt) ();
     }
 
diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c
index 3fc026f78eb..8a5f23f9824 100644
--- a/gdb/gdbserver/server.c
+++ b/gdb/gdbserver/server.c
@@ -152,13 +152,30 @@  static struct btrace_config current_btrace_conf;
 
 /* The client remote protocol state. */
 
-static client_state g_client_state;
+static struct multi_client_states g_client_states;
+
+multi_client_states &
+get_client_states ()
+{
+  return g_client_states;
+}
+
+
+/* Add a new client state for a corresponding file descriptor fd */
 
 client_state &
-get_client_state ()
+multi_client_states::add_client_state (gdb_fildes_t fd)
 {
-  client_state &cs = g_client_state;
-  return cs;
+  if (fd == -1)
+    /* This is an initial client state setup in captured main */
+      client_states[fd] = client_state ();
+  else
+    /* Initialize this client state from the initial client state.
+     * If fd was disconnected / reconnected then it is reloaded.
+     */
+    client_states[fd] = client_states[-1];
+  client_states[fd].remote_desc = fd;
+  return set_current_client (fd);
 }
 
 
@@ -3556,7 +3573,8 @@  captured_main (int argc, char *argv[])
 #endif
 
   current_directory = getcwd (NULL, 0);
-  client_state &cs = get_client_state ();
+
+  client_state &cs = get_client_states ().add_client_state (-1);
 
   if (current_directory == NULL)
     {
diff --git a/gdb/gdbserver/server.h b/gdb/gdbserver/server.h
index 3c286862349..6c2b70e8004 100644
--- a/gdb/gdbserver/server.h
+++ b/gdb/gdbserver/server.h
@@ -107,6 +107,7 @@  extern int in_queued_stop_replies (ptid_t ptid);
 #include "utils.h"
 #include "debug.h"
 #include "gdbsupport/gdb_vecs.h"
+#include <map>
 
 /* Maximum number of bytes to read/write at once.  The value here
    is chosen to fill up a packet (the headers account for the 32).  */
@@ -141,9 +142,11 @@  extern unsigned long signal_pid;
 struct client_state
 {
   client_state ():
-    own_buf ((char *) xmalloc (PBUFSIZ + 1)) 
+    own_buf ((char *) xmalloc (PBUFSIZ + 1))
   {}
 
+  gdb_fildes_t remote_desc;
+
   /* The thread set with an `Hc' packet.  `Hc' is deprecated in favor of
      `vCont'.  Note the multi-process extensions made `vCont' a
      requirement, so `Hc pPID.TID' is pretty much undefined.  So
@@ -202,7 +205,31 @@  struct client_state
 
 };
 
-client_state &get_client_state ();
+/* Container of client remote protocol states for all the currently
+   connected clients.  */
+
+#define get_client_state() get_client_states ().get_current_client ()
+
+class multi_client_states
+{
+private:
+  /*  Mapping from the file descriptor to the associated client state */
+  std::map<gdb_fildes_t, client_state> client_states;
+  /*  The file descriptor of the current client we are focused on */
+  gdb_fildes_t current_fd;
+
+public:
+  /* Return the current client we are focused on. */
+  client_state &get_current_client () { return client_states[current_fd]; }
+
+  /* Set the current client we wish to focus on. */
+  client_state &set_current_client (gdb_fildes_t fd) { current_fd = fd; return client_states[current_fd]; }
+
+  /* Add the current client we wish to focus on */
+  client_state &add_client_state (gdb_fildes_t fd);
+};
+
+struct multi_client_states &get_client_states ();
 
 #include "gdbthread.h"
 #include "inferiors.h"