gdb/serial.h

   1 /* Remote serial support interface definitions for GDB, the GNU Debugger.
   2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2004,
   3    2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef SERIAL_H
  21 #define SERIAL_H
  22
  23 #ifdef USE_WIN32API
  24 #include <winsock2.h>
  25 #include <windows.h>
  26 #endif
  27
  28 struct ui_file;
  29
  30 /* For most routines, if a failure is indicated, then errno should be
  31    examined.  */
  32
  33 /* Terminal state pointer.  This is specific to each type of
  34    interface.  */
  35
  36 typedef void *serial_ttystate;
  37 struct serial;
  38
  39 /* Try to open NAME.  Returns a new `struct serial *' on success, NULL
  40    on failure. Note that some open calls can block and, if possible,
  41    should be  written to be non-blocking, with calls to ui_look_hook
  42    so they can be cancelled. An async interface for open could be
  43    added to GDB if necessary.  */
  44
  45 extern struct serial *serial_open (const char *name);
  46
  47 /* Find an already opened serial stream using a file handle.  */
  48
  49 extern struct serial *serial_for_fd (int fd);
  50
  51 /* Open a new serial stream using a file handle.  */
  52
  53 extern struct serial *serial_fdopen (const int fd);
  54
  55 /* Push out all buffers, close the device and destroy SCB.  */
  56
  57 extern void serial_close (struct serial *scb);
  58
  59 /* Create a pipe, and put the read end in files[0], and the write end
  60    in filde[1].  Returns 0 for success, negative value for error (in
  61    which case errno contains the error).  */
  62
  63 extern int gdb_pipe (int fildes[2]);
  64
  65 /* Create a pipe with each end wrapped in a `struct serial' interface.
  66    Put the read end in scbs[0], and the write end in scbs[1].  Returns
  67    0 for success, negative value for error (in which case errno
  68    contains the error).  */
  69
  70 extern int serial_pipe (struct serial *scbs[2]);
  71
  72 /* Push out all buffers and destroy SCB without closing the device.  */
  73
  74 extern void serial_un_fdopen (struct serial *scb);
  75
  76 /* Read one char from the serial device with TIMEOUT seconds to wait
  77    or -1 to wait forever.  Use timeout of 0 to effect a poll.
  78    Infinite waits are not permitted. Returns unsigned char if ok, else
  79    one of the following codes.  Note that all error return-codes are
  80    guaranteed to be < 0.  */
  81
  82 enum serial_rc {
  83   SERIAL_ERROR = -1,    /* General error.  */
  84   SERIAL_TIMEOUT = -2,  /* Timeout or data-not-ready during read.
  85                            Unfortunately, through
  86                            deprecated_ui_loop_hook (), this can also
  87                            be a QUIT indication.  */
  88   SERIAL_EOF = -3       /* General end-of-file or remote target
  89                            connection closed, indication.  Includes
  90                            things like the line dropping dead.  */
  91 };
  92
  93 extern int serial_readchar (struct serial *scb, int timeout);
  94
  95 /* Write LEN chars from STRING to the port SCB.  Returns 0 for
  96    success, non-zero for failure.  */
  97
  98 extern int serial_write (struct serial *scb, const char *str, int len);
  99
 100 /* Write a printf style string onto the serial port.  */
 101
 102 extern void serial_printf (struct serial *desc,
 103                            const char *,...) ATTRIBUTE_PRINTF (2, 3);
 104
 105 /* Allow pending output to drain.  */
 106
 107 extern int serial_drain_output (struct serial *);
 108
 109 /* Flush (discard) pending output.  Might also flush input (if this
 110    system can't flush only output).  */
 111
 112 extern int serial_flush_output (struct serial *);
 113
 114 /* Flush pending input.  Might also flush output (if this system can't
 115    flush only input).  */
 116
 117 extern int serial_flush_input (struct serial *);
 118
 119 /* Send a break between 0.25 and 0.5 seconds long.  */
 120
 121 extern int serial_send_break (struct serial *scb);
 122
 123 /* Turn the port into raw mode.  */
 124
 125 extern void serial_raw (struct serial *scb);
 126
 127 /* Return a pointer to a newly malloc'd ttystate containing the state
 128    of the tty.  */
 129
 130 extern serial_ttystate serial_get_tty_state (struct serial *scb);
 131
 132 /* Set the state of the tty to TTYSTATE.  The change is immediate.
 133    When changing to or from raw mode, input might be discarded.
 134    Returns 0 for success, negative value for error (in which case
 135    errno contains the error).  */
 136
 137 extern int serial_set_tty_state (struct serial *scb, serial_ttystate ttystate);
 138
 139 /* printf_filtered a user-comprehensible description of ttystate on
 140    the specified STREAM. FIXME: At present this sends output to the
 141    default stream - GDB_STDOUT.  */
 142
 143 extern void serial_print_tty_state (struct serial *scb,
 144                                     serial_ttystate ttystate,
 145                                     struct ui_file *);
 146
 147 /* Set the tty state to NEW_TTYSTATE, where OLD_TTYSTATE is the
 148    current state (generally obtained from a recent call to
 149    serial_get_tty_state()), but be careful not to discard any input.
 150    This means that we never switch in or out of raw mode, even if
 151    NEW_TTYSTATE specifies a switch.  */
 152
 153 extern int serial_noflush_set_tty_state (struct serial *scb,
 154                                          serial_ttystate new_ttystate,
 155                                          serial_ttystate old_ttystate);
 156
 157 /* Set the baudrate to the decimal value supplied.  Returns 0 for
 158    success, -1 for failure.  */
 159
 160 extern int serial_setbaudrate (struct serial *scb, int rate);
 161
 162 /* Set the number of stop bits to the value specified.  Returns 0 for
 163    success, -1 for failure.  */
 164
 165 #define SERIAL_1_STOPBITS 1
 166 #define SERIAL_1_AND_A_HALF_STOPBITS 2  /* 1.5 bits, snicker...  */
 167 #define SERIAL_2_STOPBITS 3
 168
 169 extern int serial_setstopbits (struct serial *scb, int num);
 170
 171 /* Asynchronous serial interface: */
 172
 173 /* Can the serial device support asynchronous mode? */
 174
 175 extern int serial_can_async_p (struct serial *scb);
 176
 177 /* Has the serial device been put in asynchronous mode? */
 178
 179 extern int serial_is_async_p (struct serial *scb);
 180
 181 /* For ASYNC enabled devices, register a callback and enable
 182    asynchronous mode.  To disable asynchronous mode, register a NULL
 183    callback.  */
 184
 185 typedef void (serial_event_ftype) (struct serial *scb, void *context);
 186 extern void serial_async (struct serial *scb,
 187                           serial_event_ftype *handler, void *context);
 188
 189 /* Provide direct access to the underlying FD (if any) used to
 190    implement the serial device.  This interface is clearly
 191    deprecated. Will call internal_error() if the operation isn't
 192    applicable to the current serial device.  */
 193
 194 extern int deprecated_serial_fd (struct serial *scb);
 195
 196 /* Trace/debug mechanism.
 197
 198    serial_debug() enables/disables internal debugging.
 199    serial_debug_p() indicates the current debug state.  */
 200
 201 extern void serial_debug (struct serial *scb, int debug_p);
 202
 203 extern int serial_debug_p (struct serial *scb);
 204
 205
 206 /* Details of an instance of a serial object */
 207
 208 struct serial
 209   {
 210     int fd;                     /* File descriptor */
 211     /* File descriptor for a separate error stream that should be
 212        immediately forwarded to gdb_stderr.  This may be -1.
 213        If != -1, this descriptor should be non-blocking or
 214        ops->avail should be non-NULL.  */
 215     int error_fd;
 216     struct serial_ops *ops;     /* Function vector */
 217     void *state;                /* Local context info for open FD */
 218     serial_ttystate ttystate;   /* Not used (yet) */
 219     int bufcnt;                 /* Amount of data remaining in receive
 220                                    buffer.  -ve for sticky errors.  */
 221     unsigned char *bufp;        /* Current byte */
 222     unsigned char buf[BUFSIZ];  /* Da buffer itself */
 223     int current_timeout;        /* (ser-unix.c termio{,s} only), last
 224                                    value of VTIME */
 225     int timeout_remaining;      /* (ser-unix.c termio{,s} only), we
 226                                    still need to wait for this many
 227                                    more seconds.  */
 228     char *name;                 /* The name of the device or host */
 229     struct serial *next;        /* Pointer to the next `struct serial *' */
 230     int refcnt;                 /* Number of pointers to this block */
 231     int debug_p;                /* Trace this serial devices operation.  */
 232     int async_state;            /* Async internal state.  */
 233     void *async_context;        /* Async event thread's context */
 234     serial_event_ftype *async_handler;/* Async event handler */
 235   };
 236
 237 struct serial_ops
 238   {
 239     char *name;
 240     struct serial_ops *next;
 241     int (*open) (struct serial *, const char *name);
 242     void (*close) (struct serial *);
 243     int (*fdopen) (struct serial *, int fd);
 244     int (*readchar) (struct serial *, int timeout);
 245     int (*write) (struct serial *, const char *str, int len);
 246     /* Discard pending output */
 247     int (*flush_output) (struct serial *);
 248     /* Discard pending input */
 249     int (*flush_input) (struct serial *);
 250     int (*send_break) (struct serial *);
 251     void (*go_raw) (struct serial *);
 252     serial_ttystate (*get_tty_state) (struct serial *);
 253     int (*set_tty_state) (struct serial *, serial_ttystate);
 254     void (*print_tty_state) (struct serial *, serial_ttystate,
 255                              struct ui_file *);
 256     int (*noflush_set_tty_state) (struct serial *, serial_ttystate,
 257                                   serial_ttystate);
 258     int (*setbaudrate) (struct serial *, int rate);
 259     int (*setstopbits) (struct serial *, int num);
 260     /* Wait for output to drain */
 261     int (*drain_output) (struct serial *);
 262     /* Change the serial device into/out of asynchronous mode, call
 263        the specified function when ever there is something
 264        interesting.  */
 265     void (*async) (struct serial *scb, int async_p);
 266     /* Perform a low-level read operation, reading (at most) COUNT
 267        bytes into SCB->BUF.  Return zero at end of file.  */
 268     int (*read_prim)(struct serial *scb, size_t count);
 269     /* Perform a low-level write operation, writing (at most) COUNT
 270        bytes from BUF.  */
 271     int (*write_prim)(struct serial *scb, const void *buf, size_t count);
 272     /* Return that number of bytes that can be read from FD
 273        without blocking.  Return value of -1 means that the
 274        the read will not block even if less that requested bytes
 275        are available.  */
 276     int (*avail)(struct serial *scb, int fd);
 277
 278 #ifdef USE_WIN32API
 279     /* Return a handle to wait on, indicating available data from SCB
 280        when signaled, in *READ.  Return a handle indicating errors
 281        in *EXCEPT.  */
 282     void (*wait_handle) (struct serial *scb, HANDLE *read, HANDLE *except);
 283     void (*done_wait_handle) (struct serial *scb);
 284 #endif /* USE_WIN32API */
 285   };
 286
 287 /* Add a new serial interface to the interface list */
 288
 289 extern void serial_add_interface (struct serial_ops * optable);
 290
 291 /* File in which to record the remote debugging session */
 292
 293 extern void serial_log_command (const char *);
 294
 295 #ifdef USE_WIN32API
 296
 297 /* Windows-only: find or create handles that we can wait on for this
 298    serial device.  */
 299 extern void serial_wait_handle (struct serial *, HANDLE *, HANDLE *);
 300
 301 /* Windows-only: signal that we are done with the wait handles.  */
 302 extern void serial_done_wait_handle (struct serial *);
 303
 304 #endif /* USE_WIN32API */
 305
 306 #endif /* SERIAL_H */