diff options
Diffstat (limited to 'gcc/cp/input.c')
| -rwxr-xr-x | gcc/cp/input.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/gcc/cp/input.c b/gcc/cp/input.c new file mode 100755 index 0000000..376546b --- /dev/null +++ b/gcc/cp/input.c @@ -0,0 +1,213 @@ +/* Input handling for G++. + Copyright (C) 1992, 93-98, 1999 Free Software Foundation, Inc. + Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing. + +This file is part of GNU CC. + +GNU CC 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 2, or (at your option) +any later version. + +GNU CC 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. + +You should have received a copy of the GNU General Public License +along with GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +/* G++ needs to do enough saving and re-parsing of text that it is + necessary to abandon the simple FILE* model and use a mechanism where + we can pre-empt one input stream with another derived from saved text; + we may need to do this arbitrarily often, and cannot depend on having + the GNU library available, so FILE objects just don't cut it. + + This file is written as a separate module, but can be included by + lex.c for very minor efficiency gains (primarily in function + inlining). */ + +#include "system.h" + +extern FILE *finput; + +struct input_source { + /* saved string */ + char *str; + int length; + /* current position, when reading as input */ + int offset; + /* linked list maintenance */ + struct input_source *next; + /* values to restore after reading all of current string */ + char *filename; + int lineno; + struct pending_input *input; + int putback_char; +}; + +static struct input_source *input, *free_inputs; + +extern char *input_filename; +extern int lineno; + +#ifdef __GNUC__ +#define inline __inline__ +#else +#define inline +#endif + +#if USE_CPPLIB +extern unsigned char *yy_cur, *yy_lim; +extern int yy_get_token (); +#define GETC() (yy_cur < yy_lim ? *yy_cur++ : yy_get_token ()) +#else +#define GETC() getc (finput) +#endif + +extern void feed_input PROTO((char *, int)); +extern void put_input PROTO((int)); +extern void put_back PROTO((int)); +extern int getch PROTO((void)); +extern int input_redirected PROTO((void)); + +static inline struct input_source * allocate_input PROTO((void)); +static inline void free_input PROTO((struct input_source *)); +static inline void end_input PROTO((void)); +static inline int sub_getch PROTO((void)); + +static inline struct input_source * +allocate_input () +{ + struct input_source *inp; + if (free_inputs) + { + inp = free_inputs; + free_inputs = inp->next; + inp->next = 0; + return inp; + } + inp = (struct input_source *) xmalloc (sizeof (struct input_source)); + inp->next = 0; + return inp; +} + +static inline void +free_input (inp) + struct input_source *inp; +{ + inp->str = 0; + inp->length = 0; + inp->next = free_inputs; + free_inputs = inp; +} + +static int putback_char = -1; + +/* Some of these external functions are declared inline in case this file + is included in lex.c. */ + +inline +void +feed_input (str, len) + char *str; + int len; +{ + struct input_source *inp = allocate_input (); + + /* This shouldn't be necessary. */ + while (len && !str[len-1]) + len--; + + inp->str = str; + inp->length = len; + inp->offset = 0; + inp->next = input; + inp->filename = input_filename; + inp->lineno = lineno; + inp->input = save_pending_input (); + inp->putback_char = putback_char; + putback_char = -1; + input = inp; +} + +struct pending_input *to_be_restored; /* XXX */ +extern int end_of_file; + +static inline void +end_input () +{ + struct input_source *inp = input; + + end_of_file = 0; + input = inp->next; + input_filename = inp->filename; + lineno = inp->lineno; + /* Get interface/implementation back in sync. */ + extract_interface_info (); + putback_char = inp->putback_char; + restore_pending_input (inp->input); + free_input (inp); +} + +static inline int +sub_getch () +{ + if (putback_char != -1) + { + int ch = putback_char; + putback_char = -1; + return ch; + } + if (input) + { + if (input->offset >= input->length) + { + my_friendly_assert (putback_char == -1, 223); + ++(input->offset); + if (input->offset - input->length < 64) + return EOF; + + /* We must be stuck in an error-handling rule; give up. */ + end_input (); + return getch (); + } + return (unsigned char)input->str[input->offset++]; + } + return GETC (); +} + +inline +void +put_back (ch) + int ch; +{ + if (ch != EOF) + { + my_friendly_assert (putback_char == -1, 224); + putback_char = ch; + } +} + +extern int linemode; + +int +getch () +{ + int ch = sub_getch (); + if (linemode && ch == '\n') + { + put_back (ch); + ch = EOF; + } + return ch; +} + +inline +int +input_redirected () +{ + return input != 0; +} |