gdb/serial.h

   1 /* Remote serial support interface definitions for GDB, the GNU Debugger.
   2    Copyright (C) 1992-1996, 1998-2001, 2004-2012 Free Software
   3    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.  The new serial object has a reference count of 1.
  41    Note that some open calls can block and, if possible, should be
  42    written to be non-blocking, with calls to ui_look_hook so they can
  43    be cancelled.  An async interface for open could be added to GDB if
  44    necessary.  */
  45
  46 extern struct serial *serial_open (const char *name);
  47
  48 /* Returns true if SCB is open.  */
  49
  50 extern int serial_is_open (struct serial *scb);
  51
  52 /* Find an already opened serial stream using a file handle.  */
  53
  54 extern struct serial *serial_for_fd (int fd);
  55
  56 /* Open a new serial stream using a file handle.  */
  57
  58 extern struct serial *serial_fdopen (const int fd);
  59
  60 /* Push out all buffers, close the device and unref SCB.  */
  61
  62 extern void serial_close (struct serial *scb);
  63
  64 /* Increment reference count of SCB.  */
  65
  66 extern void serial_ref (struct serial *scb);
  67
  68 /* Decrement reference count of SCB.  */
  69
  70 extern void serial_unref (struct serial *scb);
  71
  72 /* Create a pipe, and put the read end in files[0], and the write end
  73    in filde[1].  Returns 0 for success, negative value for error (in
  74    which case errno contains the error).  */
  75
  76 extern int gdb_pipe (int fildes[2]);
  77
  78 /* Create a pipe with each end wrapped in a `struct serial' interface.
  79    Put the read end in scbs[0], and the write end in scbs[1].  Returns
  80    0 for success, negative value for error (in which case errno
  81    contains the error).  */
  82
  83 extern int serial_pipe (struct serial *scbs[2]);
  84
  85 /* Push out all buffers and destroy SCB without closing the device.  */
  86
  87 extern void serial_un_fdopen (struct serial *scb);
  88
  89 /* Read one char from the serial device with TIMEOUT seconds to wait
  90    or -1 to wait forever.  Use timeout of 0 to effect a poll.
  91    Infinite waits are not permitted.  Returns unsigned char if ok, else
  92    one of the following codes.  Note that all error return-codes are
  93    guaranteed to be < 0.  */
  94
  95 enum serial_rc {
  96   SERIAL_ERROR = -1,    /* General error.  */
  97   SERIAL_TIMEOUT = -2,  /* Timeout or data-not-ready during read.
  98                            Unfortunately, through
  99                            deprecated_ui_loop_hook (), this can also
 100                            be a QUIT indication.  */
 101   SERIAL_EOF = -3       /* General end-of-file or remote target
 102                            connection closed, indication.  Includes
 103                            things like the line dropping dead.  */
 104 };
 105
 106 extern int serial_readchar (struct serial *scb, int timeout);
 107
 108 /* Write LEN chars from STRING to the port SCB.  Returns 0 for
 109    success, non-zero for failure.  */
 110
 111 extern int serial_write (struct serial *scb, const char *str, int len);
 112
 113 /* Write a printf style string onto the serial port.  */
 114
 115 extern void serial_printf (struct serial *desc,
 116                            const char *,...) ATTRIBUTE_PRINTF (2, 3);
 117
 118 /* Allow pending output to drain.  */
 119
 120 extern int serial_drain_output (struct serial *);
 121
 122 /* Flush (discard) pending output.  Might also flush input (if this
 123    system can't flush only output).  */
 124
 125 extern int serial_flush_output (struct serial *);
 126
 127 /* Flush pending input.  Might also flush output (if this system can't
 128    flush only input).  */
 129
 130 extern int serial_flush_input (struct serial *);
 131
 132 /* Send a break between 0.25 and 0.5 seconds long.  */
 133
 134 extern int serial_send_break (struct serial *scb);
 135
 136 /* Turn the port into raw mode.  */
 137
 138 extern void serial_raw (struct serial *scb);
 139
 140 /* Return a pointer to a newly malloc'd ttystate containing the state
 141    of the tty.  */
 142
 143 extern serial_ttystate serial_get_tty_state (struct serial *scb);
 144
 145 /* Return a pointer to a newly malloc'd ttystate containing a copy
 146    of the state in TTYSTATE.  */
 147
 148 extern serial_ttystate serial_copy_tty_state (struct serial *scb,
 149                                               serial_ttystate ttystate);
 150
 151 /* Set the state of the tty to TTYSTATE.  The change is immediate.
 152    When changing to or from raw mode, input might be discarded.
 153    Returns 0 for success, negative value for error (in which case
 154    errno contains the error).  */
 155
 156 extern int serial_set_tty_state (struct serial *scb, serial_ttystate ttystate);
 157
 158 /* printf_filtered a user-comprehensible description of ttystate on
 159    the specified STREAM.  FIXME: At present this sends output to the
 160    default stream - GDB_STDOUT.  */
 161
 162 extern void serial_print_tty_state (struct serial *scb,
 163                                     serial_ttystate ttystate,
 164                                     struct ui_file *);
 165
 166 /* Set the tty state to NEW_TTYSTATE, where OLD_TTYSTATE is the
 167    current state (generally obtained from a recent call to
 168    serial_get_tty_state()), but be careful not to discard any input.
 169    This means that we never switch in or out of raw mode, even if
 170    NEW_TTYSTATE specifies a switch.  */
 171
 172 extern int serial_noflush_set_tty_state (struct serial *scb,
 173                                          serial_ttystate new_ttystate,
 174                                          serial_ttystate old_ttystate);
 175
 176 /* Set the baudrate to the decimal value supplied.  Returns 0 for
 177    success, -1 for failure.  */
 178
 179 extern int serial_setbaudrate (struct serial *scb, int rate);
 180
 181 /* Set the number of stop bits to the value specified.  Returns 0 for
 182    success, -1 for failure.  */
 183
 184 #define SERIAL_1_STOPBITS 1
 185 #define SERIAL_1_AND_A_HALF_STOPBITS 2  /* 1.5 bits, snicker...  */
 186 #define SERIAL_2_STOPBITS 3
 187
 188 extern int serial_setstopbits (struct serial *scb, int num);
 189
 190 /* Asynchronous serial interface: */
 191
 192 /* Can the serial device support asynchronous mode?  */
 193
 194 extern int serial_can_async_p (struct serial *scb);
 195
 196 /* Has the serial device been put in asynchronous mode?  */
 197
 198 extern int serial_is_async_p (struct serial *scb);
 199
 200 /* For ASYNC enabled devices, register a callback and enable
 201    asynchronous mode.  To disable asynchronous mode, register a NULL
 202    callback.  */
 203
 204 typedef void (serial_event_ftype) (struct serial *scb, void *context);
 205 extern void serial_async (struct serial *scb,
 206                           serial_event_ftype *handler, void *context);
 207
 208 /* Provide direct access to the underlying FD (if any) used to
 209    implement the serial device.  This interface is clearly
 210    deprecated.  Will call internal_error() if the operation isn't
 211    applicable to the current serial device.  */
 212
 213 extern int deprecated_serial_fd (struct serial *scb);
 214
 215 /* Trace/debug mechanism.
 216
 217    serial_debug() enables/disables internal debugging.
 218    serial_debug_p() indicates the current debug state.  */
 219
 220 extern void serial_debug (struct serial *scb, int debug_p);
 221
 222 extern int serial_debug_p (struct serial *scb);
 223
 224
 225 /* Details of an instance of a serial object.  */
 226
 227 struct serial
 228   {
 229     /* serial objects are ref counted (but not the underlying
 230        connection, just the object's lifetime in memory).  */
 231     int refcnt;
 232
 233     int fd;                     /* File descriptor */
 234     /* File descriptor for a separate error stream that should be
 235        immediately forwarded to gdb_stderr.  This may be -1.
 236        If != -1, this descriptor should be non-blocking or
 237        ops->avail should be non-NULL.  */
 238     int error_fd;
 239     struct serial_ops *ops;     /* Function vector */
 240     void *state;                /* Local context info for open FD */
 241     serial_ttystate ttystate;   /* Not used (yet) */
 242     int bufcnt;                 /* Amount of data remaining in receive
 243                                    buffer.  -ve for sticky errors.  */
 244     unsigned char *bufp;        /* Current byte */
 245     unsigned char buf[BUFSIZ];  /* Da buffer itself */
 246     int current_timeout;        /* (ser-unix.c termio{,s} only), last
 247                                    value of VTIME */
 248     int timeout_remaining;      /* (ser-unix.c termio{,s} only), we
 249                                    still need to wait for this many
 250                                    more seconds.  */
 251     char *name;                 /* The name of the device or host */
 252     struct serial *next;        /* Pointer to the next `struct serial *' */
 253     int debug_p;                /* Trace this serial devices operation.  */
 254     int async_state;            /* Async internal state.  */
 255     void *async_context;        /* Async event thread's context */
 256     serial_event_ftype *async_handler;/* Async event handler */
 257   };
 258
 259 struct serial_ops
 260   {
 261     char *name;
 262     struct serial_ops *next;
 263     int (*open) (struct serial *, const char *name);
 264     void (*close) (struct serial *);
 265     int (*fdopen) (struct serial *, int fd);
 266     int (*readchar) (struct serial *, int timeout);
 267     int (*write) (struct serial *, const char *str, int len);
 268     /* Discard pending output */
 269     int (*flush_output) (struct serial *);
 270     /* Discard pending input */
 271     int (*flush_input) (struct serial *);
 272     int (*send_break) (struct serial *);
 273     void (*go_raw) (struct serial *);
 274     serial_ttystate (*get_tty_state) (struct serial *);
 275     serial_ttystate (*copy_tty_state) (struct serial *, serial_ttystate);
 276     int (*set_tty_state) (struct serial *, serial_ttystate);
 277     void (*print_tty_state) (struct serial *, serial_ttystate,
 278                              struct ui_file *);
 279     int (*noflush_set_tty_state) (struct serial *, serial_ttystate,
 280                                   serial_ttystate);
 281     int (*setbaudrate) (struct serial *, int rate);
 282     int (*setstopbits) (struct serial *, int num);
 283     /* Wait for output to drain.  */
 284     int (*drain_output) (struct serial *);
 285     /* Change the serial device into/out of asynchronous mode, call
 286        the specified function when ever there is something
 287        interesting.  */
 288     void (*async) (struct serial *scb, int async_p);
 289     /* Perform a low-level read operation, reading (at most) COUNT
 290        bytes into SCB->BUF.  Return zero at end of file.  */
 291     int (*read_prim)(struct serial *scb, size_t count);
 292     /* Perform a low-level write operation, writing (at most) COUNT
 293        bytes from BUF.  */
 294     int (*write_prim)(struct serial *scb, const void *buf, size_t count);
 295     /* Return that number of bytes that can be read from FD
 296        without blocking.  Return value of -1 means that the
 297        read will not block even if less that requested bytes
 298        are available.  */
 299     int (*avail)(struct serial *scb, int fd);
 300
 301 #ifdef USE_WIN32API
 302     /* Return a handle to wait on, indicating available data from SCB
 303        when signaled, in *READ.  Return a handle indicating errors
 304        in *EXCEPT.  */
 305     void (*wait_handle) (struct serial *scb, HANDLE *read, HANDLE *except);
 306     void (*done_wait_handle) (struct serial *scb);
 307 #endif /* USE_WIN32API */
 308   };
 309
 310 /* Add a new serial interface to the interface list.  */
 311
 312 extern void serial_add_interface (struct serial_ops * optable);
 313
 314 /* File in which to record the remote debugging session.  */
 315
 316 extern void serial_log_command (const char *);
 317
 318 #ifdef USE_WIN32API
 319
 320 /* Windows-only: find or create handles that we can wait on for this
 321    serial device.  */
 322 extern void serial_wait_handle (struct serial *, HANDLE *, HANDLE *);
 323
 324 /* Windows-only: signal that we are done with the wait handles.  */
 325 extern void serial_done_wait_handle (struct serial *);
 326
 327 #endif /* USE_WIN32API */
 328
 329 #endif /* SERIAL_H */