/* Generic serial interface functions.
- Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2003,
- 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 1992-2022 Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "serial.h"
#include "ser-base.h"
-#include "event-loop.h"
+#include "gdbsupport/event-loop.h"
-#include "gdb_select.h"
-#include "gdb_string.h"
-#include <sys/time.h>
+#include "gdbsupport/gdb_select.h"
+#include "gdbsupport/gdb_sys_time.h"
#ifdef USE_WIN32API
#include <winsock2.h>
#endif
/* Value of scb->async_state: */
enum {
- /* >= 0 (TIMER_SCHEDULED) */
- /* The ID of the currently scheduled timer event. This state is
- rarely encountered. Timer events are one-off so as soon as the
- event is delivered the state is shanged to NOTHING_SCHEDULED. */
- FD_SCHEDULED = -1,
+ /* When >= 0, this contains the ID of the currently scheduled timer event.
+ This state is rarely encountered. Timer events are one-off so as soon as
+ the event is delivered the state is changed to NOTHING_SCHEDULED. */
+
/* The fd_event() handler is scheduled. It is called when ever the
file descriptor becomes ready. */
- NOTHING_SCHEDULED = -2
+ FD_SCHEDULED = -1,
+
/* Either no task is scheduled (just going into ASYNC mode) or a
timer event has just gone off and the current state has been
forced into nothing scheduled. */
+ NOTHING_SCHEDULED = -2
};
/* Identify and schedule the next ASYNC task based on scb->async_state
case NOTHING_SCHEDULED:
if (scb->bufcnt == 0)
{
- add_file_handler (scb->fd, fd_event, scb);
+ add_file_handler (scb->fd, fd_event, scb, "serial");
next_state = FD_SCHEDULED;
}
else
if (scb->bufcnt == 0)
{
delete_timer (scb->async_state);
- add_file_handler (scb->fd, fd_event, scb);
+ add_file_handler (scb->fd, fd_event, scb, "serial");
next_state = FD_SCHEDULED;
}
else
}
}
+/* Run the SCB's async handle, and reschedule, if the handler doesn't
+ close SCB. */
+
+static void
+run_async_handler_and_reschedule (struct serial *scb)
+{
+ int is_open;
+
+ /* Take a reference, so a serial_close call within the handler
+ doesn't make SCB a dangling pointer. */
+ serial_ref (scb);
+
+ /* Run the handler. */
+ scb->async_handler (scb, scb->async_context);
+
+ is_open = serial_is_open (scb);
+ serial_unref (scb);
+
+ /* Get ready for more, if not already closed. */
+ if (is_open)
+ reschedule (scb);
+}
+
/* FD_EVENT: This is scheduled when the input FIFO is empty (and there
is no pending error). As soon as data arrives, it is read into the
input FIFO and the client notified. The client should then drain
static void
fd_event (int error, void *context)
{
- struct serial *scb = context;
+ struct serial *scb = (struct serial *) context;
if (error != 0)
{
scb->bufcnt = SERIAL_ERROR;
else if (scb->bufcnt == 0)
{
/* Prime the input FIFO. The readchar() function is used to
- pull characters out of the buffer. See also
- generic_readchar(). */
+ pull characters out of the buffer. See also
+ generic_readchar(). */
int nr;
- nr = scb->ops->read_prim (scb, BUFSIZ);
+
+ do
+ {
+ nr = scb->ops->read_prim (scb, BUFSIZ);
+ }
+ while (nr < 0 && errno == EINTR);
+
if (nr == 0)
{
scb->bufcnt = SERIAL_EOF;
scb->bufcnt = SERIAL_ERROR;
}
}
- scb->async_handler (scb, scb->async_context);
- reschedule (scb);
+ run_async_handler_and_reschedule (scb);
}
/* PUSH_EVENT: The input FIFO is non-empty (or there is a pending
error). Nag the client until all the data has been read. In the
case of errors, the client will need to close or de-async the
- device before naging stops. */
+ device before nagging stops. */
static void
push_event (void *context)
{
- struct serial *scb = context;
+ struct serial *scb = (struct serial *) context;
scb->async_state = NOTHING_SCHEDULED; /* Timers are one-off */
- scb->async_handler (scb, scb->async_context);
- /* re-schedule */
- reschedule (scb);
+ run_async_handler_and_reschedule (scb);
}
/* Wait for input on scb, with timeout seconds. Returns 0 on success,
otherwise SERIAL_TIMEOUT or SERIAL_ERROR. */
+/* NOTE: Some of the code below is dead. The only possible values of
+ the TIMEOUT parameter are ONE and ZERO. OTOH, we should probably
+ get rid of the deprecated_ui_loop_hook call in do_ser_base_readchar
+ instead and support infinite time outs here. */
+
static int
ser_base_wait_for (struct serial *scb, int timeout)
{
int numfds;
struct timeval tv;
fd_set readfds, exceptfds;
+ int nfds;
/* NOTE: Some OS's can scramble the READFDS when the select()
- call fails (ex the kernel with Red Hat 5.2). Initialize all
- arguments before each call. */
+ call fails (ex the kernel with Red Hat 5.2). Initialize all
+ arguments before each call. */
tv.tv_sec = timeout;
tv.tv_usec = 0;
FD_SET (scb->fd, &readfds);
FD_SET (scb->fd, &exceptfds);
+ QUIT;
+
+ nfds = scb->fd + 1;
if (timeout >= 0)
- numfds = gdb_select (scb->fd + 1, &readfds, 0, &exceptfds, &tv);
+ numfds = interruptible_select (nfds, &readfds, 0, &exceptfds, &tv);
else
- numfds = gdb_select (scb->fd + 1, &readfds, 0, &exceptfds, 0);
+ numfds = interruptible_select (nfds, &readfds, 0, &exceptfds, 0);
if (numfds <= 0)
{
}
}
-/* Read a character with user-specified timeout. TIMEOUT is number of seconds
- to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns
- char if successful. Returns -2 if timeout expired, EOF if line dropped
- dead, or -3 for any other error (see errno in that case). */
+/* Read any error output we might have. */
+
+static void
+ser_base_read_error_fd (struct serial *scb, int close_fd)
+{
+ if (scb->error_fd != -1)
+ {
+ ssize_t s;
+ char buf[GDB_MI_MSG_WIDTH + 1];
+
+ for (;;)
+ {
+ char *current;
+ char *newline;
+ int to_read = GDB_MI_MSG_WIDTH;
+ int num_bytes = -1;
+
+ if (scb->ops->avail)
+ num_bytes = (scb->ops->avail)(scb, scb->error_fd);
+
+ if (num_bytes != -1)
+ to_read = (num_bytes < to_read) ? num_bytes : to_read;
+
+ if (to_read == 0)
+ break;
+
+ s = read (scb->error_fd, &buf, to_read);
+ if ((s == -1) || (s == 0 && !close_fd))
+ break;
+
+ if (s == 0 && close_fd)
+ {
+ /* End of file. */
+ if (serial_is_async_p (scb))
+ delete_file_handler (scb->error_fd);
+ close (scb->error_fd);
+ scb->error_fd = -1;
+ break;
+ }
+
+ /* In theory, embedded newlines are not a problem.
+ But for MI, we want each output line to have just
+ one newline for legibility. So output things
+ in newline chunks. */
+ gdb_assert (s > 0 && s <= GDB_MI_MSG_WIDTH);
+ buf[s] = '\0';
+ current = buf;
+ while ((newline = strstr (current, "\n")) != NULL)
+ {
+ *newline = '\0';
+ fputs_unfiltered (current, gdb_stderr);
+ fputs_unfiltered ("\n", gdb_stderr);
+ current = newline + 1;
+ }
+
+ fputs_unfiltered (current, gdb_stderr);
+ }
+ }
+}
+
+/* Event-loop callback for a serial's error_fd. Flushes any error
+ output we might have. */
+
+static void
+handle_error_fd (int error, gdb_client_data client_data)
+{
+ serial *scb = (serial *) client_data;
+
+ ser_base_read_error_fd (scb, 0);
+}
+
+/* Read a character with user-specified timeout. TIMEOUT is number of
+ seconds to wait, or -1 to wait forever. Use timeout of 0 to effect
+ a poll. Returns char if successful. Returns SERIAL_TIMEOUT if
+ timeout expired, SERIAL_EOF if line dropped dead, or SERIAL_ERROR
+ for any other error (see errno in that case). */
static int
do_ser_base_readchar (struct serial *scb, int timeout)
while (1)
{
/* N.B. The UI may destroy our world (for instance by calling
- remote_stop,) in which case we want to get out of here as
- quickly as possible. It is not safe to touch scb, since
- someone else might have freed it. The
- deprecated_ui_loop_hook signals that we should exit by
- returning 1. */
+ remote_stop,) in which case we want to get out of here as
+ quickly as possible. It is not safe to touch scb, since
+ someone else might have freed it. The
+ deprecated_ui_loop_hook signals that we should exit by
+ returning 1. */
if (deprecated_ui_loop_hook)
{
status = ser_base_wait_for (scb, delta);
if (timeout > 0)
- timeout -= delta;
+ timeout -= delta;
/* If we got a character or an error back from wait_for, then we can
- break from the loop before the timeout is completed. */
+ break from the loop before the timeout is completed. */
if (status != SERIAL_TIMEOUT)
break;
/* If we have exhausted the original timeout, then generate
- a SERIAL_TIMEOUT, and pass it out of the loop. */
+ a SERIAL_TIMEOUT, and pass it out of the loop. */
else if (timeout == 0)
{
status = SERIAL_TIMEOUT;
break;
}
+
+ /* We also need to check and consume the stderr because it could
+ come before the stdout for some stubs. If we just sit and wait
+ for stdout, we would hit a deadlock for that case. */
+ ser_base_read_error_fd (scb, 0);
}
if (status < 0)
return status;
- status = scb->ops->read_prim (scb, BUFSIZ);
+ do
+ {
+ status = scb->ops->read_prim (scb, BUFSIZ);
+ }
+ while (status < 0 && errno == EINTR);
if (status <= 0)
{
if (status == 0)
- return SERIAL_EOF;
+ return SERIAL_EOF;
else
/* Got an error from read. */
return SERIAL_ERROR;
}
}
}
- /* Read any error output we might have. */
- if (scb->error_fd != -1)
- {
- ssize_t s;
- char buf[81];
-
- for (;;)
- {
- char *current;
- char *newline;
- int to_read = 80;
-
- int num_bytes = -1;
- if (scb->ops->avail)
- num_bytes = (scb->ops->avail)(scb, scb->error_fd);
- if (num_bytes != -1)
- to_read = (num_bytes < to_read) ? num_bytes : to_read;
-
- if (to_read == 0)
- break;
-
- s = read (scb->error_fd, &buf, to_read);
- if (s == -1)
- break;
- if (s == 0)
- {
- /* EOF */
- close (scb->error_fd);
- scb->error_fd = -1;
- break;
- }
- /* In theory, embedded newlines are not a problem.
- But for MI, we want each output line to have just
- one newline for legibility. So output things
- in newline chunks. */
- buf[s] = '\0';
- current = buf;
- while ((newline = strstr (current, "\n")) != NULL)
- {
- *newline = '\0';
- fputs_unfiltered (current, gdb_stderr);
- fputs_unfiltered ("\n", gdb_stderr);
- current = newline + 1;
- }
- fputs_unfiltered (current, gdb_stderr);
- }
- }
+ /* Read any error output we might have. */
+ ser_base_read_error_fd (scb, 1);
reschedule (scb);
return ch;
}
int
-ser_base_write (struct serial *scb, const char *str, int len)
+ser_base_write (struct serial *scb, const void *buf, size_t count)
{
+ const char *str = (const char *) buf;
int cc;
- while (len > 0)
+ while (count > 0)
{
- cc = scb->ops->write_prim (scb, str, len);
+ QUIT;
+
+ cc = scb->ops->write_prim (scb, str, count);
if (cc < 0)
- return 1;
- len -= cc;
+ {
+ if (errno == EINTR)
+ continue;
+ return 1;
+ }
+ count -= cc;
str += cc;
}
return 0;
ser_base_get_tty_state (struct serial *scb)
{
/* Allocate a dummy. */
- return (serial_ttystate) XMALLOC (int);
+ return (serial_ttystate) XNEW (int);
}
-int
-ser_base_set_tty_state (struct serial *scb, serial_ttystate ttystate)
+serial_ttystate
+ser_base_copy_tty_state (struct serial *scb, serial_ttystate ttystate)
{
- return 0;
+ /* Allocate another dummy. */
+ return (serial_ttystate) XNEW (int);
}
int
-ser_base_noflush_set_tty_state (struct serial *scb,
- serial_ttystate new_ttystate,
- serial_ttystate old_ttystate)
+ser_base_set_tty_state (struct serial *scb, serial_ttystate ttystate)
{
return 0;
}
return 0; /* Never fails! */
}
+/* Implement the "setparity" serial_ops callback. */
+
+int
+ser_base_setparity (struct serial *scb, int parity)
+{
+ return 0; /* Never fails! */
+}
+
/* Put the SERIAL device into/out-of ASYNC mode. */
void
fprintf_unfiltered (gdb_stdlog, "[fd%d->asynchronous]\n",
scb->fd);
reschedule (scb);
+
+ if (scb->error_fd != -1)
+ add_file_handler (scb->error_fd, handle_error_fd, scb, "serial-error");
}
else
{
delete_timer (scb->async_state);
break;
}
+
+ if (scb->error_fd != -1)
+ delete_file_handler (scb->error_fd);
}
}