6 /* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004,
7 * 2006, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public License
11 * as published by the Free Software Foundation; either version 3 of
12 * the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
27 #include "libguile/__scm.h"
32 #include "libguile/gc.h"
33 #include "libguile/tags.h"
34 #include "libguile/error.h"
35 #include "libguile/print.h"
36 #include "libguile/struct.h"
37 #include "libguile/threads.h"
38 #include "libguile/strings.h"
42 #define SCM_INITIAL_PUTBACK_BUF_SIZE 4
44 /* values for the rw_active flag. */
45 typedef enum scm_t_port_rw_active
{
49 } scm_t_port_rw_active
;
51 /* C representation of a Scheme port. */
55 SCM port
; /* Link back to the port object. */
56 #if SCM_USE_PTHREAD_THREADS
57 scm_i_pthread_mutex_t lock
; /* A recursive lock for this port. */
60 int revealed
; /* 0 not revealed, > 1 revealed.
61 * Revealed ports do not get GC'd.
63 /* data for the underlying port implementation as a raw C value. */
66 SCM file_name
; /* debugging support. */
67 long line_number
; /* debugging support. */
68 int column_number
; /* debugging support. */
70 /* Character encoding support */
72 scm_t_string_failed_conversion_handler ilseq_handler
;
74 /* port buffers. the buffer(s) are set up for all ports.
75 in the case of string ports, the buffer is the string itself.
76 in the case of unbuffered file ports, the buffer is a
77 single char: shortbuf. */
79 /* this buffer is filled from read_buf to read_end using the ptob
80 buffer_fill. then input requests are taken from read_pos until
81 it reaches read_end. */
83 unsigned char *read_buf
; /* buffer start. */
84 const unsigned char *read_pos
;/* the next unread char. */
85 unsigned char *read_end
; /* pointer to last buffered char + 1. */
86 scm_t_off read_buf_size
; /* size of the buffer. */
88 /* when chars are put back into the buffer, e.g., using peek-char or
89 unread-string, the read-buffer pointers are switched to cbuf.
90 the original pointers are saved here and restored when the put-back
91 chars have been consumed. */
92 unsigned char *saved_read_buf
;
93 const unsigned char *saved_read_pos
;
94 unsigned char *saved_read_end
;
95 scm_t_off saved_read_buf_size
;
97 /* write requests are saved into this buffer at write_pos until it
98 reaches write_buf + write_buf_size, then the ptob flush is
101 unsigned char *write_buf
; /* buffer start. */
102 unsigned char *write_pos
; /* pointer to last buffered char + 1. */
103 unsigned char *write_end
; /* pointer to end of buffer + 1. */
104 scm_t_off write_buf_size
; /* size of the buffer. */
106 unsigned char shortbuf
; /* buffer for "unbuffered" streams. */
108 int rw_random
; /* true if the port is random access.
109 implies that the buffers must be
110 flushed before switching between
111 reading and writing, seeking, etc. */
113 scm_t_port_rw_active rw_active
; /* for random access ports,
114 indicates which of the buffers
115 is currently in use. can be
116 SCM_PORT_WRITE, SCM_PORT_READ,
117 or SCM_PORT_NEITHER. */
120 /* a buffer for un-read chars and strings. */
121 unsigned char *putback_buf
;
122 size_t putback_buf_size
; /* allocated size of putback_buf. */
124 /* input/output iconv conversion descriptors */
130 SCM_INTERNAL SCM scm_i_port_weak_set
;
133 #define SCM_READ_BUFFER_EMPTY_P(c_port) (c_port->read_pos >= c_port->read_end)
137 #define SCM_EOF_OBJECT_P(x) (scm_is_eq ((x), SCM_EOF_VAL))
140 * A set of flags characterizes a port.
141 * Note that we reserve the bits 1 << 24 and above for use by the
142 * routines in the port's scm_ptobfuns structure.
144 #define SCM_OPN (1L<<16) /* Is the port open? */
145 #define SCM_RDNG (2L<<16) /* Is it a readable port? */
146 #define SCM_WRTNG (4L<<16) /* Is it writable? */
147 #define SCM_BUF0 (8L<<16) /* Is it unbuffered? */
148 #define SCM_BUFLINE (64L<<16) /* Is it line-buffered? */
150 #define SCM_PORTP(x) (SCM_HAS_TYP7 (x, scm_tc7_port))
151 #define SCM_OPPORTP(x) (SCM_PORTP (x) && (SCM_CELL_WORD_0 (x) & SCM_OPN))
152 #define SCM_INPUT_PORT_P(x) (SCM_PORTP (x) && (SCM_CELL_WORD_0 (x) & SCM_RDNG))
153 #define SCM_OUTPUT_PORT_P(x) (SCM_PORTP (x) && (SCM_CELL_WORD_0 (x) & SCM_WRTNG))
154 #define SCM_OPINPORTP(x) (SCM_OPPORTP (x) && SCM_INPUT_PORT_P (x))
155 #define SCM_OPOUTPORTP(x) (SCM_OPPORTP (x) && SCM_OUTPUT_PORT_P (x))
156 #define SCM_OPENP(x) (SCM_OPPORTP (x))
157 #define SCM_CLOSEDP(x) (!SCM_OPENP (x))
158 #define SCM_CLR_PORT_OPEN_FLAG(p) \
159 SCM_SET_CELL_WORD_0 ((p), SCM_CELL_WORD_0 (p) & ~SCM_OPN)
161 #define SCM_PTAB_ENTRY(x) ((scm_t_port *) SCM_CELL_WORD_1 (x))
162 #define SCM_PORT_DESCRIPTOR(port) ((scm_t_ptob_descriptor *) SCM_CELL_WORD_2 (port))
163 #define SCM_SETPTAB_ENTRY(x, ent) (SCM_SET_CELL_WORD_1 ((x), (scm_t_bits) (ent)))
164 #define SCM_STREAM(x) (SCM_PTAB_ENTRY(x)->stream)
165 #define SCM_SETSTREAM(x, s) (SCM_PTAB_ENTRY(x)->stream = (scm_t_bits) (s))
166 #define SCM_FILENAME(x) (SCM_PTAB_ENTRY(x)->file_name)
167 #define SCM_SET_FILENAME(x, n) (SCM_PTAB_ENTRY(x)->file_name = (n))
168 #define SCM_LINUM(x) (SCM_PTAB_ENTRY(x)->line_number)
169 #define SCM_COL(x) (SCM_PTAB_ENTRY(x)->column_number)
170 #define SCM_REVEALED(x) (SCM_PTAB_ENTRY(x)->revealed)
171 #define SCM_SETREVEALED(x, s) (SCM_PTAB_ENTRY(x)->revealed = (s))
173 #define SCM_INCLINE(port) do {SCM_LINUM (port) += 1; SCM_COL (port) = 0;} while (0)
174 #define SCM_ZEROCOL(port) do {SCM_COL (port) = 0;} while (0)
175 #define SCM_INCCOL(port) do {SCM_COL (port) += 1;} while (0)
176 #define SCM_DECCOL(port) do {if (SCM_COL (port) > 0) SCM_COL (port) -= 1;} while (0)
177 #define SCM_TABCOL(port) do {SCM_COL (port) += 8 - SCM_COL (port) % 8;} while (0)
179 /* Maximum number of port types. */
180 #define SCM_I_MAX_PORT_TYPE_COUNT 256
184 /* port-type description. */
185 typedef struct scm_t_ptob_descriptor
189 size_t (*free
) (SCM
);
190 int (*print
) (SCM exp
, SCM port
, scm_print_state
*pstate
);
191 SCM (*equalp
) (SCM
, SCM
);
192 int (*close
) (SCM port
);
194 void (*write
) (SCM port
, const void *data
, size_t size
);
195 void (*flush
) (SCM port
);
197 void (*end_input
) (SCM port
, int offset
);
198 int (*fill_input
) (SCM port
);
199 int (*input_waiting
) (SCM port
);
201 scm_t_off (*seek
) (SCM port
, scm_t_off OFFSET
, int WHENCE
);
202 void (*truncate
) (SCM port
, scm_t_off length
);
204 } scm_t_ptob_descriptor
;
206 #define SCM_TC2PTOBNUM(x) (0x0ff & ((x) >> 8))
207 #define SCM_PTOBNUM(x) (SCM_TC2PTOBNUM (SCM_CELL_TYPE (x)))
208 /* SCM_PTOBNAME can be 0 if name is missing */
209 #define SCM_PTOBNAME(ptobnum) (scm_c_port_type_ref (ptobnum)->name)
211 /* Port types, and their vtables. */
212 SCM_INTERNAL
long scm_c_num_port_types (void);
213 SCM_API scm_t_ptob_descriptor
* scm_c_port_type_ref (long ptobnum
);
214 SCM_API
long scm_c_port_type_add_x (scm_t_ptob_descriptor
*desc
);
215 SCM_API scm_t_bits
scm_make_port_type (char *name
,
216 int (*fill_input
) (SCM port
),
217 void (*write
) (SCM port
,
220 SCM_API
void scm_set_port_mark (scm_t_bits tc
, SCM (*mark
) (SCM
));
221 SCM_API
void scm_set_port_free (scm_t_bits tc
, size_t (*free
) (SCM
));
222 SCM_API
void scm_set_port_print (scm_t_bits tc
,
223 int (*print
) (SCM exp
,
225 scm_print_state
*pstate
));
226 SCM_API
void scm_set_port_equalp (scm_t_bits tc
, SCM (*equalp
) (SCM
, SCM
));
227 SCM_API
void scm_set_port_close (scm_t_bits tc
, int (*close
) (SCM
));
229 SCM_API
void scm_set_port_flush (scm_t_bits tc
, void (*flush
) (SCM port
));
230 SCM_API
void scm_set_port_end_input (scm_t_bits tc
,
231 void (*end_input
) (SCM port
,
233 SCM_API
void scm_set_port_seek (scm_t_bits tc
,
234 scm_t_off (*seek
) (SCM port
,
237 SCM_API
void scm_set_port_truncate (scm_t_bits tc
,
238 void (*truncate
) (SCM port
,
240 SCM_API
void scm_set_port_input_waiting (scm_t_bits tc
, int (*input_waiting
) (SCM
));
242 /* The input, output, error, and load ports. */
243 SCM_API SCM
scm_current_input_port (void);
244 SCM_API SCM
scm_current_output_port (void);
245 SCM_API SCM
scm_current_error_port (void);
246 SCM_API SCM
scm_current_load_port (void);
247 SCM_API SCM
scm_set_current_input_port (SCM port
);
248 SCM_API SCM
scm_set_current_output_port (SCM port
);
249 SCM_API SCM
scm_set_current_error_port (SCM port
);
250 SCM_API
void scm_dynwind_current_input_port (SCM port
);
251 SCM_API
void scm_dynwind_current_output_port (SCM port
);
252 SCM_API
void scm_dynwind_current_error_port (SCM port
);
253 SCM_INTERNAL
void scm_i_dynwind_current_load_port (SCM port
);
256 SCM_INTERNAL
long scm_i_mode_bits (SCM modes
);
257 SCM_API
long scm_mode_bits (char *modes
);
258 SCM_API SCM
scm_port_mode (SCM port
);
260 /* Low-level constructors. */
262 scm_c_make_port_with_encoding (scm_t_bits tag
,
263 unsigned long mode_bits
,
264 const char *encoding
,
265 scm_t_string_failed_conversion_handler handler
,
267 SCM_API SCM
scm_c_make_port (scm_t_bits tag
, unsigned long mode_bits
,
269 SCM_API SCM
scm_new_port_table_entry (scm_t_bits tag
);
272 SCM_API SCM
scm_port_p (SCM x
);
273 SCM_API SCM
scm_input_port_p (SCM x
);
274 SCM_API SCM
scm_output_port_p (SCM x
);
275 SCM_API SCM
scm_port_closed_p (SCM port
);
276 SCM_API SCM
scm_eof_object_p (SCM x
);
279 SCM_API SCM
scm_close_port (SCM port
);
280 SCM_API SCM
scm_close_input_port (SCM port
);
281 SCM_API SCM
scm_close_output_port (SCM port
);
283 /* Encoding characters to byte streams, and decoding byte streams to
285 SCM_INTERNAL
const char *scm_i_default_port_encoding (void);
286 SCM_INTERNAL
void scm_i_set_default_port_encoding (const char *);
287 SCM_INTERNAL
void scm_i_set_port_encoding_x (SCM port
, const char *str
);
288 SCM_API SCM
scm_port_encoding (SCM port
);
289 SCM_API SCM
scm_set_port_encoding_x (SCM port
, SCM encoding
);
290 SCM_INTERNAL scm_t_string_failed_conversion_handler
scm_i_get_conversion_strategy (SCM port
);
291 SCM_INTERNAL
void scm_i_set_conversion_strategy_x (SCM port
,
292 scm_t_string_failed_conversion_handler h
);
293 SCM_API SCM
scm_port_conversion_strategy (SCM port
);
294 SCM_API SCM
scm_set_port_conversion_strategy_x (SCM port
, SCM behavior
);
296 /* Acquiring and releasing the port lock. */
297 SCM_INLINE
int scm_c_lock_port (SCM port
);
298 SCM_INLINE
int scm_c_try_lock_port (SCM port
);
299 SCM_INLINE
int scm_c_unlock_port (SCM port
);
301 /* Revealed counts. */
302 SCM_API
int scm_revealed_count (SCM port
);
303 SCM_API SCM
scm_port_revealed (SCM port
);
304 SCM_API SCM
scm_set_port_revealed_x (SCM port
, SCM rcount
);
305 SCM_API SCM
scm_adjust_port_revealed_x (SCM port
, SCM addend
);
308 SCM_API
int scm_get_byte_or_eof (SCM port
);
309 SCM_INLINE
int scm_get_byte_or_eof_unlocked (SCM port
);
310 SCM_API
int scm_peek_byte_or_eof (SCM port
);
311 SCM_INLINE
int scm_peek_byte_or_eof_unlocked (SCM port
);
312 SCM_API
size_t scm_c_read (SCM port
, void *buffer
, size_t size
);
313 SCM_API
size_t scm_c_read_unlocked (SCM port
, void *buffer
, size_t size
);
314 SCM_API scm_t_wchar
scm_getc (SCM port
);
315 SCM_API scm_t_wchar
scm_getc_unlocked (SCM port
);
316 SCM_API SCM
scm_read_char (SCM port
);
319 SCM_INTERNAL
void scm_unget_byte (int c
, SCM port
);
320 SCM_INTERNAL
void scm_unget_byte_unlocked (int c
, SCM port
);
321 SCM_API
void scm_ungetc (scm_t_wchar c
, SCM port
);
322 SCM_API
void scm_ungetc_unlocked (scm_t_wchar c
, SCM port
);
323 SCM_API
void scm_ungets (const char *s
, int n
, SCM port
);
324 SCM_API
void scm_ungets_unlocked (const char *s
, int n
, SCM port
);
325 SCM_API SCM
scm_peek_char (SCM port
);
326 SCM_API SCM
scm_unread_char (SCM cobj
, SCM port
);
327 SCM_API SCM
scm_unread_string (SCM str
, SCM port
);
329 /* Manipulating the buffers. */
330 SCM_API
void scm_port_non_buffer (scm_t_port
*pt
);
331 SCM_API
int scm_fill_input (SCM port
);
332 SCM_INTERNAL
size_t scm_take_from_input_buffers (SCM port
, char *dest
, size_t read_len
);
333 SCM_API SCM
scm_drain_input (SCM port
);
334 SCM_API
void scm_end_input (SCM port
);
335 SCM_API SCM
scm_force_output (SCM port
);
336 SCM_API
void scm_flush (SCM port
);
339 SCM_INLINE
void scm_putc (char c
, SCM port
);
340 SCM_INLINE
void scm_puts (const char *str_data
, SCM port
);
341 SCM_API
void scm_c_write (SCM port
, const void *buffer
, size_t size
);
342 SCM_API
void scm_lfwrite (const char *ptr
, size_t size
, SCM port
);
343 SCM_INTERNAL
void scm_lfwrite_substr (SCM str
, size_t start
, size_t end
,
346 /* Querying and setting positions, and character availability. */
347 SCM_API SCM
scm_char_ready_p (SCM port
);
348 SCM_API SCM
scm_seek (SCM object
, SCM offset
, SCM whence
);
349 SCM_API SCM
scm_truncate_file (SCM object
, SCM length
);
350 SCM_API SCM
scm_port_line (SCM port
);
351 SCM_API SCM
scm_set_port_line_x (SCM port
, SCM line
);
352 SCM_API SCM
scm_port_column (SCM port
);
353 SCM_API SCM
scm_set_port_column_x (SCM port
, SCM line
);
354 SCM_API SCM
scm_port_filename (SCM port
);
355 SCM_API SCM
scm_set_port_filename_x (SCM port
, SCM filename
);
357 /* Implementation helpers for port printing functions. */
358 SCM_API
int scm_port_print (SCM exp
, SCM port
, scm_print_state
*);
359 SCM_API
void scm_print_port_mode (SCM exp
, SCM port
);
361 /* Iterating over all ports. */
362 SCM_API SCM
scm_port_for_each (SCM proc
);
363 SCM_API
void scm_c_port_for_each (void (*proc
)(void *data
, SCM p
), void *data
);
364 SCM_API SCM
scm_flush_all_ports (void);
367 SCM_API SCM
scm_void_port (char * mode_str
);
368 SCM_API SCM
scm_sys_make_void_port (SCM mode
);
370 /* Initialization. */
371 SCM_INTERNAL
void scm_init_ports (void);
374 /* Inline function implementations. */
376 #if SCM_CAN_INLINE || defined SCM_INLINE_C_IMPLEMENTING_INLINES
377 SCM_INLINE_IMPLEMENTATION
int
378 scm_c_lock_port (SCM port
)
380 #if SCM_USE_PTHREAD_THREADS
381 return scm_i_pthread_mutex_lock (&SCM_PTAB_ENTRY (port
)->lock
);
387 SCM_INLINE_IMPLEMENTATION
int
388 scm_c_try_lock_port (SCM port
)
390 #if SCM_USE_PTHREAD_THREADS
391 return scm_i_pthread_mutex_trylock (&SCM_PTAB_ENTRY (port
)->lock
);
397 SCM_INLINE_IMPLEMENTATION
int
398 scm_c_unlock_port (SCM port
)
400 #if SCM_USE_PTHREAD_THREADS
401 return scm_i_pthread_mutex_unlock (&SCM_PTAB_ENTRY (port
)->lock
);
407 SCM_INLINE_IMPLEMENTATION
int
408 scm_get_byte_or_eof_unlocked (SCM port
)
411 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
413 if (pt
->rw_active
== SCM_PORT_WRITE
)
414 /* may be marginally faster than calling scm_flush. */
415 SCM_PORT_DESCRIPTOR (port
)->flush (port
);
418 pt
->rw_active
= SCM_PORT_READ
;
420 if (pt
->read_pos
>= pt
->read_end
)
422 if (SCM_UNLIKELY (scm_fill_input (port
) == EOF
))
426 c
= *(pt
->read_pos
++);
431 /* Like `scm_get_byte_or_eof' but does not change PORT's `read_pos'. */
432 SCM_INLINE_IMPLEMENTATION
int
433 scm_peek_byte_or_eof_unlocked (SCM port
)
436 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
438 if (pt
->rw_active
== SCM_PORT_WRITE
)
439 /* may be marginally faster than calling scm_flush. */
440 SCM_PORT_DESCRIPTOR (port
)->flush (port
);
443 pt
->rw_active
= SCM_PORT_READ
;
445 if (pt
->read_pos
>= pt
->read_end
)
447 if (SCM_UNLIKELY (scm_fill_input (port
) == EOF
))
456 SCM_INLINE_IMPLEMENTATION
void
457 scm_putc (char c
, SCM port
)
459 SCM_ASSERT_TYPE (SCM_OPOUTPORTP (port
), port
, 0, NULL
, "output port");
460 scm_lfwrite (&c
, 1, port
);
463 SCM_INLINE_IMPLEMENTATION
void
464 scm_puts (const char *s
, SCM port
)
466 SCM_ASSERT_TYPE (SCM_OPOUTPORTP (port
), port
, 0, NULL
, "output port");
467 scm_lfwrite (s
, strlen (s
), port
);
469 #endif /* SCM_CAN_INLINE || defined SCM_INLINE_C_IMPLEMENTING_INLINES */
471 #endif /* SCM_PORTS_H */