/* Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
Contributed by Andy Vaught
F2003 I/O support contributed by Jerry DeLisle
This file is part of the GNU Fortran 95 runtime library (libgfortran).
Libgfortran is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
Libgfortran is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
. */
#ifndef GFOR_IO_H
#define GFOR_IO_H
/* IO library include. */
#include "libgfortran.h"
#include
/* Forward declarations. */
struct st_parameter_dt;
typedef struct stream stream;
struct fbuf;
struct format_data;
typedef struct fnode fnode;
struct gfc_unit;
/* Macros for testing what kinds of I/O we are doing. */
#define is_array_io(dtp) ((dtp)->internal_unit_desc)
#define is_internal_unit(dtp) ((dtp)->u.p.unit_is_internal)
#define is_stream_io(dtp) ((dtp)->u.p.current_unit->flags.access == ACCESS_STREAM)
#define is_char4_unit(dtp) ((dtp)->u.p.unit_is_internal && (dtp)->common.unit)
/* The array_loop_spec contains the variables for the loops over index ranges
that are encountered. Since the variables can be negative, ssize_t
is used. */
typedef struct array_loop_spec
{
/* Index counter for this dimension. */
ssize_t idx;
/* Start for the index counter. */
ssize_t start;
/* End for the index counter. */
ssize_t end;
/* Step for the index counter. */
ssize_t step;
}
array_loop_spec;
/* A stucture to build a hash table for format data. */
#define FORMAT_HASH_SIZE 16
typedef struct format_hash_entry
{
char *key;
gfc_charlen_type key_len;
struct format_data *hashed_fmt;
}
format_hash_entry;
/* Representation of a namelist object in libgfortran
Namelist Records
&GROUPNAME OBJECT=value[s] [,OBJECT=value[s]].../
or
&GROUPNAME OBJECT=value[s] [,OBJECT=value[s]]...&END
The object can be a fully qualified, compound name for an intrinsic
type, derived types or derived type components. So, a substring
a(:)%b(4)%ch(2:4)(1:7) has to be treated correctly in namelist
read. Hence full information about the structure of the object has
to be available to list_read.c and write.
These requirements are met by the following data structures.
namelist_info type contains all the scalar information about the
object and arrays of descriptor_dimension and array_loop_spec types for
arrays. */
typedef struct namelist_type
{
/* Object type. */
bt type;
/* Object name. */
char * var_name;
/* Address for the start of the object's data. */
void * mem_pos;
/* Flag to show that a read is to be attempted for this node. */
int touched;
/* Length of intrinsic type in bytes. */
int len;
/* Rank of the object. */
int var_rank;
/* Overall size of the object in bytes. */
index_type size;
/* Length of character string. */
index_type string_length;
descriptor_dimension * dim;
array_loop_spec * ls;
struct namelist_type * next;
}
namelist_info;
/* Options for the OPEN statement. */
typedef enum
{ ACCESS_SEQUENTIAL, ACCESS_DIRECT, ACCESS_APPEND, ACCESS_STREAM,
ACCESS_UNSPECIFIED
}
unit_access;
typedef enum
{ ACTION_READ, ACTION_WRITE, ACTION_READWRITE,
ACTION_UNSPECIFIED
}
unit_action;
typedef enum
{ BLANK_NULL, BLANK_ZERO, BLANK_UNSPECIFIED }
unit_blank;
typedef enum
{ DELIM_NONE, DELIM_APOSTROPHE, DELIM_QUOTE,
DELIM_UNSPECIFIED
}
unit_delim;
typedef enum
{ FORM_FORMATTED, FORM_UNFORMATTED, FORM_UNSPECIFIED }
unit_form;
typedef enum
{ POSITION_ASIS, POSITION_REWIND, POSITION_APPEND,
POSITION_UNSPECIFIED
}
unit_position;
typedef enum
{ STATUS_UNKNOWN, STATUS_OLD, STATUS_NEW, STATUS_SCRATCH,
STATUS_REPLACE, STATUS_UNSPECIFIED
}
unit_status;
typedef enum
{ PAD_YES, PAD_NO, PAD_UNSPECIFIED }
unit_pad;
typedef enum
{ DECIMAL_POINT, DECIMAL_COMMA, DECIMAL_UNSPECIFIED }
unit_decimal;
typedef enum
{ ENCODING_UTF8, ENCODING_DEFAULT, ENCODING_UNSPECIFIED }
unit_encoding;
typedef enum
{ ROUND_UP, ROUND_DOWN, ROUND_ZERO, ROUND_NEAREST, ROUND_COMPATIBLE,
ROUND_PROCDEFINED, ROUND_UNSPECIFIED }
unit_round;
/* NOTE: unit_sign must correspond with the sign_status enumerator in
st_parameter_dt to not break the ABI. */
typedef enum
{ SIGN_PROCDEFINED, SIGN_SUPPRESS, SIGN_PLUS, SIGN_UNSPECIFIED }
unit_sign;
typedef enum
{ ADVANCE_YES, ADVANCE_NO, ADVANCE_UNSPECIFIED }
unit_advance;
typedef enum
{READING, WRITING}
unit_mode;
typedef enum
{ ASYNC_YES, ASYNC_NO, ASYNC_UNSPECIFIED }
unit_async;
typedef enum
{ SIGN_S, SIGN_SS, SIGN_SP }
unit_sign_s;
#define CHARACTER1(name) \
char * name; \
gfc_charlen_type name ## _len
#define CHARACTER2(name) \
gfc_charlen_type name ## _len; \
char * name
typedef struct
{
st_parameter_common common;
GFC_INTEGER_4 recl_in;
CHARACTER2 (file);
CHARACTER1 (status);
CHARACTER2 (access);
CHARACTER1 (form);
CHARACTER2 (blank);
CHARACTER1 (position);
CHARACTER2 (action);
CHARACTER1 (delim);
CHARACTER2 (pad);
CHARACTER1 (convert);
CHARACTER2 (decimal);
CHARACTER1 (encoding);
CHARACTER2 (round);
CHARACTER1 (sign);
CHARACTER2 (asynchronous);
GFC_INTEGER_4 *newunit;
}
st_parameter_open;
#define IOPARM_CLOSE_HAS_STATUS (1 << 7)
typedef struct
{
st_parameter_common common;
CHARACTER1 (status);
}
st_parameter_close;
typedef struct
{
st_parameter_common common;
}
st_parameter_filepos;
#define IOPARM_INQUIRE_HAS_EXIST (1 << 7)
#define IOPARM_INQUIRE_HAS_OPENED (1 << 8)
#define IOPARM_INQUIRE_HAS_NUMBER (1 << 9)
#define IOPARM_INQUIRE_HAS_NAMED (1 << 10)
#define IOPARM_INQUIRE_HAS_NEXTREC (1 << 11)
#define IOPARM_INQUIRE_HAS_RECL_OUT (1 << 12)
#define IOPARM_INQUIRE_HAS_STRM_POS_OUT (1 << 13)
#define IOPARM_INQUIRE_HAS_FILE (1 << 14)
#define IOPARM_INQUIRE_HAS_ACCESS (1 << 15)
#define IOPARM_INQUIRE_HAS_FORM (1 << 16)
#define IOPARM_INQUIRE_HAS_BLANK (1 << 17)
#define IOPARM_INQUIRE_HAS_POSITION (1 << 18)
#define IOPARM_INQUIRE_HAS_ACTION (1 << 19)
#define IOPARM_INQUIRE_HAS_DELIM (1 << 20)
#define IOPARM_INQUIRE_HAS_PAD (1 << 21)
#define IOPARM_INQUIRE_HAS_NAME (1 << 22)
#define IOPARM_INQUIRE_HAS_SEQUENTIAL (1 << 23)
#define IOPARM_INQUIRE_HAS_DIRECT (1 << 24)
#define IOPARM_INQUIRE_HAS_FORMATTED (1 << 25)
#define IOPARM_INQUIRE_HAS_UNFORMATTED (1 << 26)
#define IOPARM_INQUIRE_HAS_READ (1 << 27)
#define IOPARM_INQUIRE_HAS_WRITE (1 << 28)
#define IOPARM_INQUIRE_HAS_READWRITE (1 << 29)
#define IOPARM_INQUIRE_HAS_CONVERT (1 << 30)
#define IOPARM_INQUIRE_HAS_FLAGS2 (1 << 31)
#define IOPARM_INQUIRE_HAS_ASYNCHRONOUS (1 << 0)
#define IOPARM_INQUIRE_HAS_DECIMAL (1 << 1)
#define IOPARM_INQUIRE_HAS_ENCODING (1 << 2)
#define IOPARM_INQUIRE_HAS_ROUND (1 << 3)
#define IOPARM_INQUIRE_HAS_SIGN (1 << 4)
#define IOPARM_INQUIRE_HAS_PENDING (1 << 5)
#define IOPARM_INQUIRE_HAS_SIZE (1 << 6)
#define IOPARM_INQUIRE_HAS_ID (1 << 7)
typedef struct
{
st_parameter_common common;
GFC_INTEGER_4 *exist, *opened, *number, *named;
GFC_INTEGER_4 *nextrec, *recl_out;
GFC_IO_INT *strm_pos_out;
CHARACTER1 (file);
CHARACTER2 (access);
CHARACTER1 (form);
CHARACTER2 (blank);
CHARACTER1 (position);
CHARACTER2 (action);
CHARACTER1 (delim);
CHARACTER2 (pad);
CHARACTER1 (name);
CHARACTER2 (sequential);
CHARACTER1 (direct);
CHARACTER2 (formatted);
CHARACTER1 (unformatted);
CHARACTER2 (read);
CHARACTER1 (write);
CHARACTER2 (readwrite);
CHARACTER1 (convert);
GFC_INTEGER_4 flags2;
CHARACTER1 (asynchronous);
CHARACTER2 (decimal);
CHARACTER1 (encoding);
CHARACTER2 (round);
CHARACTER1 (sign);
GFC_INTEGER_4 *pending;
GFC_IO_INT *size;
GFC_INTEGER_4 *id;
}
st_parameter_inquire;
#define IOPARM_DT_LIST_FORMAT (1 << 7)
#define IOPARM_DT_NAMELIST_READ_MODE (1 << 8)
#define IOPARM_DT_HAS_REC (1 << 9)
#define IOPARM_DT_HAS_SIZE (1 << 10)
#define IOPARM_DT_HAS_IOLENGTH (1 << 11)
#define IOPARM_DT_HAS_FORMAT (1 << 12)
#define IOPARM_DT_HAS_ADVANCE (1 << 13)
#define IOPARM_DT_HAS_INTERNAL_UNIT (1 << 14)
#define IOPARM_DT_HAS_NAMELIST_NAME (1 << 15)
#define IOPARM_DT_HAS_ID (1 << 16)
#define IOPARM_DT_HAS_POS (1 << 17)
#define IOPARM_DT_HAS_ASYNCHRONOUS (1 << 18)
#define IOPARM_DT_HAS_BLANK (1 << 19)
#define IOPARM_DT_HAS_DECIMAL (1 << 20)
#define IOPARM_DT_HAS_DELIM (1 << 21)
#define IOPARM_DT_HAS_PAD (1 << 22)
#define IOPARM_DT_HAS_ROUND (1 << 23)
#define IOPARM_DT_HAS_SIGN (1 << 24)
#define IOPARM_DT_HAS_F2003 (1 << 25)
/* Internal use bit. */
#define IOPARM_DT_IONML_SET (1 << 31)
typedef struct st_parameter_dt
{
st_parameter_common common;
GFC_IO_INT rec;
GFC_IO_INT *size, *iolength;
gfc_array_char *internal_unit_desc;
CHARACTER1 (format);
CHARACTER2 (advance);
CHARACTER1 (internal_unit);
CHARACTER2 (namelist_name);
/* Private part of the structure. The compiler just needs
to reserve enough space. */
union
{
struct
{
void (*transfer) (struct st_parameter_dt *, bt, void *, int,
size_t, size_t);
struct gfc_unit *current_unit;
/* Item number in a formatted data transfer. Also used in namelist
read_logical as an index into line_buffer. */
int item_count;
unit_mode mode;
unit_blank blank_status;
unit_sign sign_status;
int scale_factor;
int max_pos; /* Maximum righthand column written to. */
/* Number of skips + spaces to be done for T and X-editing. */
int skips;
/* Number of spaces to be done for T and X-editing. */
int pending_spaces;
/* Whether an EOR condition was encountered. Value is:
0 if no EOR was encountered
1 if an EOR was encountered due to a 1-byte marker (LF)
2 if an EOR was encountered due to a 2-bytes marker (CRLF) */
int sf_seen_eor;
unit_advance advance_status;
unsigned reversion_flag : 1; /* Format reversion has occurred. */
unsigned first_item : 1;
unsigned seen_dollar : 1;
unsigned eor_condition : 1;
unsigned no_leading_blank : 1;
unsigned char_flag : 1;
unsigned input_complete : 1;
unsigned at_eol : 1;
unsigned comma_flag : 1;
/* A namelist specific flag used in the list directed library
to flag that calls are being made from namelist read (eg. to
ignore comments or to treat '/' as a terminator) */
unsigned namelist_mode : 1;
/* A namelist specific flag used in the list directed library
to flag read errors and return, so that an attempt can be
made to read a new object name. */
unsigned nml_read_error : 1;
/* A sequential formatted read specific flag used to signal that a
character string is being read so don't use commas to shorten a
formatted field width. */
unsigned sf_read_comma : 1;
/* A namelist specific flag used to enable reading input from
line_buffer for logical reads. */
unsigned line_buffer_enabled : 1;
/* An internal unit specific flag used to identify that the associated
unit is internal. */
unsigned unit_is_internal : 1;
/* An internal unit specific flag to signify an EOF condition for list
directed read. */
unsigned at_eof : 1;
/* Used for g0 floating point output. */
unsigned g0_no_blanks : 1;
/* Used to signal use of free_format_data. */
unsigned format_not_saved : 1;
/* 14 unused bits. */
/* Used for ungetc() style functionality. Possible values
are an unsigned char, EOF, or EOF - 1 used to mark the
field as not valid. */
int last_char;
char nml_delim;
int repeat_count;
int saved_length;
int saved_used;
bt saved_type;
char *saved_string;
char *scratch;
char *line_buffer;
struct format_data *fmt;
namelist_info *ionml;
/* A flag used to identify when a non-standard expanded namelist read
has occurred. */
int expanded_read;
/* Storage area for values except for strings. Must be
large enough to hold a complex value (two reals) of the
largest kind. */
char value[32];
GFC_IO_INT size_used;
} p;
/* This pad size must be equal to the pad_size declared in
trans-io.c (gfc_build_io_library_fndecls). The above structure
must be smaller or equal to this array. */
char pad[16 * sizeof (char *) + 32 * sizeof (int)];
} u;
GFC_INTEGER_4 *id;
GFC_IO_INT pos;
CHARACTER1 (asynchronous);
CHARACTER2 (blank);
CHARACTER1 (decimal);
CHARACTER2 (delim);
CHARACTER1 (pad);
CHARACTER2 (round);
CHARACTER1 (sign);
}
st_parameter_dt;
/* Ensure st_parameter_dt's u.pad is bigger or equal to u.p. */
extern char check_st_parameter_dt[sizeof (((st_parameter_dt *) 0)->u.pad)
>= sizeof (((st_parameter_dt *) 0)->u.p)
? 1 : -1];
#define IOPARM_WAIT_HAS_ID (1 << 7)
typedef struct
{
st_parameter_common common;
CHARACTER1 (id);
}
st_parameter_wait;
#undef CHARACTER1
#undef CHARACTER2
typedef struct
{
unit_access access;
unit_action action;
unit_blank blank;
unit_delim delim;
unit_form form;
int is_notpadded;
unit_position position;
unit_status status;
unit_pad pad;
unit_convert convert;
int has_recl;
unit_decimal decimal;
unit_encoding encoding;
unit_round round;
unit_sign sign;
unit_async async;
}
unit_flags;
typedef struct gfc_unit
{
int unit_number;
stream *s;
/* Treap links. */
struct gfc_unit *left, *right;
int priority;
int read_bad, current_record, saved_pos, previous_nonadvancing_write;
enum
{ NO_ENDFILE, AT_ENDFILE, AFTER_ENDFILE }
endfile;
unit_mode mode;
unit_flags flags;
unit_pad pad_status;
unit_decimal decimal_status;
unit_delim delim_status;
unit_round round_status;
/* recl -- Record length of the file.
last_record -- Last record number read or written
maxrec -- Maximum record number in a direct access file
bytes_left -- Bytes left in current record.
strm_pos -- Current position in file for STREAM I/O.
recl_subrecord -- Maximum length for subrecord.
bytes_left_subrecord -- Bytes left in current subrecord. */
gfc_offset recl, last_record, maxrec, bytes_left, strm_pos,
recl_subrecord, bytes_left_subrecord;
/* Set to 1 if we have read a subrecord. */
int continued;
__gthread_mutex_t lock;
/* Number of threads waiting to acquire this unit's lock.
When non-zero, close_unit doesn't only removes the unit
from the UNIT_ROOT tree, but doesn't free it and the
last of the waiting threads will do that.
This must be either atomically increased/decreased, or
always guarded by UNIT_LOCK. */
int waiting;
/* Flag set by close_unit if the unit as been closed.
Must be manipulated under unit's lock. */
int closed;
/* For traversing arrays */
array_loop_spec *ls;
int rank;
int file_len;
char *file;
/* The format hash table. */
struct format_hash_entry format_hash_table[FORMAT_HASH_SIZE];
/* Formatting buffer. */
struct fbuf *fbuf;
}
gfc_unit;
/* unit.c */
/* Maximum file offset, computed at library initialization time. */
extern gfc_offset max_offset;
internal_proto(max_offset);
/* Unit number to be assigned when NEWUNIT is used in an OPEN statement. */
extern GFC_INTEGER_4 next_available_newunit;
internal_proto(next_available_newunit);
/* Unit tree root. */
extern gfc_unit *unit_root;
internal_proto(unit_root);
extern __gthread_mutex_t unit_lock;
internal_proto(unit_lock);
extern int close_unit (gfc_unit *);
internal_proto(close_unit);
extern gfc_unit *get_internal_unit (st_parameter_dt *);
internal_proto(get_internal_unit);
extern void free_internal_unit (st_parameter_dt *);
internal_proto(free_internal_unit);
extern gfc_unit *find_unit (int);
internal_proto(find_unit);
extern gfc_unit *find_or_create_unit (int);
internal_proto(find_or_create_unit);
extern gfc_unit *get_unit (st_parameter_dt *, int);
internal_proto(get_unit);
extern void unlock_unit (gfc_unit *);
internal_proto(unlock_unit);
extern void update_position (gfc_unit *);
internal_proto(update_position);
extern void finish_last_advance_record (gfc_unit *u);
internal_proto (finish_last_advance_record);
extern int unit_truncate (gfc_unit *, gfc_offset, st_parameter_common *);
internal_proto (unit_truncate);
extern GFC_INTEGER_4 get_unique_unit_number (st_parameter_open *);
internal_proto(get_unique_unit_number);
/* open.c */
extern gfc_unit *new_unit (st_parameter_open *, gfc_unit *, unit_flags *);
internal_proto(new_unit);
/* transfer.c */
#define SCRATCH_SIZE 300
extern const char *type_name (bt);
internal_proto(type_name);
extern void * read_block_form (st_parameter_dt *, int *);
internal_proto(read_block_form);
extern void * read_block_form4 (st_parameter_dt *, int *);
internal_proto(read_block_form4);
extern void *write_block (st_parameter_dt *, int);
internal_proto(write_block);
extern gfc_offset next_array_record (st_parameter_dt *, array_loop_spec *,
int*);
internal_proto(next_array_record);
extern gfc_offset init_loop_spec (gfc_array_char *, array_loop_spec *,
gfc_offset *);
internal_proto(init_loop_spec);
extern void next_record (st_parameter_dt *, int);
internal_proto(next_record);
extern void reverse_memcpy (void *, const void *, size_t);
internal_proto (reverse_memcpy);
extern void st_wait (st_parameter_wait *);
export_proto(st_wait);
extern void hit_eof (st_parameter_dt *);
internal_proto(hit_eof);
/* read.c */
extern void set_integer (void *, GFC_INTEGER_LARGEST, int);
internal_proto(set_integer);
extern GFC_UINTEGER_LARGEST max_value (int, int);
internal_proto(max_value);
extern int convert_real (st_parameter_dt *, void *, const char *, int);
internal_proto(convert_real);
extern void read_a (st_parameter_dt *, const fnode *, char *, int);
internal_proto(read_a);
extern void read_a_char4 (st_parameter_dt *, const fnode *, char *, int);
internal_proto(read_a);
extern void read_f (st_parameter_dt *, const fnode *, char *, int);
internal_proto(read_f);
extern void read_l (st_parameter_dt *, const fnode *, char *, int);
internal_proto(read_l);
extern void read_x (st_parameter_dt *, int);
internal_proto(read_x);
extern void read_radix (st_parameter_dt *, const fnode *, char *, int, int);
internal_proto(read_radix);
extern void read_decimal (st_parameter_dt *, const fnode *, char *, int);
internal_proto(read_decimal);
/* list_read.c */
extern void list_formatted_read (st_parameter_dt *, bt, void *, int, size_t,
size_t);
internal_proto(list_formatted_read);
extern void finish_list_read (st_parameter_dt *);
internal_proto(finish_list_read);
extern void namelist_read (st_parameter_dt *);
internal_proto(namelist_read);
extern void namelist_write (st_parameter_dt *);
internal_proto(namelist_write);
/* write.c */
extern void write_a (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_a);
extern void write_a_char4 (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_a_char4);
extern void write_b (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_b);
extern void write_d (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_d);
extern void write_e (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_e);
extern void write_en (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_en);
extern void write_es (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_es);
extern void write_f (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_f);
extern void write_i (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_i);
extern void write_l (st_parameter_dt *, const fnode *, char *, int);
internal_proto(write_l);
extern void write_o (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_o);
extern void write_real (st_parameter_dt *, const char *, int);
internal_proto(write_real);
extern void write_real_g0 (st_parameter_dt *, const char *, int, int);
internal_proto(write_real_g0);
extern void write_x (st_parameter_dt *, int, int);
internal_proto(write_x);
extern void write_z (st_parameter_dt *, const fnode *, const char *, int);
internal_proto(write_z);
extern void list_formatted_write (st_parameter_dt *, bt, void *, int, size_t,
size_t);
internal_proto(list_formatted_write);
/* size_from_kind.c */
extern size_t size_from_real_kind (int);
internal_proto(size_from_real_kind);
extern size_t size_from_complex_kind (int);
internal_proto(size_from_complex_kind);
/* lock.c */
extern void free_ionml (st_parameter_dt *);
internal_proto(free_ionml);
static inline void
inc_waiting_locked (gfc_unit *u)
{
#ifdef HAVE_SYNC_FETCH_AND_ADD
(void) __sync_fetch_and_add (&u->waiting, 1);
#else
u->waiting++;
#endif
}
static inline int
predec_waiting_locked (gfc_unit *u)
{
#ifdef HAVE_SYNC_FETCH_AND_ADD
return __sync_add_and_fetch (&u->waiting, -1);
#else
return --u->waiting;
#endif
}
static inline void
dec_waiting_unlocked (gfc_unit *u)
{
#ifdef HAVE_SYNC_FETCH_AND_ADD
(void) __sync_fetch_and_add (&u->waiting, -1);
#else
__gthread_mutex_lock (&unit_lock);
u->waiting--;
__gthread_mutex_unlock (&unit_lock);
#endif
}
#endif