mirror/flex
1
0
Fork 0
mirror of https://github.com/westes/flex.git synced 2026-01-26 15:39:06 +00:00
Code Issues Packages Projects Releases Wiki Activity

Deprecate input(); document yyinput() for the C back end...

Browse Source 
...leaving an "input" macro in place for legacy compatibility.

input() had already become yyinput() in the C++ back end in order to
avoid collision with predefibed C++ inoput. In a multi-language world,
this is good policy in general.  There's no real reason for C to
be different, and excellent reason to pull all possible entry
points into the yy namespace.
This commit is contained in:
Eric S. Raymond 2020-10-11 21:55:00 -04:00
parent 526be1f459
commit dad680611b
6 changed files with 28 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
doc/flex.texi
View File

@ -1409,8 +1409,8 @@ elsewhere, or build your scanner using @code{%array} instead
Finally, note that you cannot put back @samp{EOF} to attempt to mark the
input stream with an end-of-file.
@cindex input()
@code{input()} reads the next character from the input stream. For
@cindex yyinput()
@code{yyinput()} reads the next character from the input stream. For
example, the following is one way to eat up C comments:
@cindex comments, discarding
@ -1423,13 +1423,13 @@ example, the following is one way to eat up C comments:
for ( ; ; )
{
while ( (c = input()) != '*' &&
while ( (c = yyinput()) != '*' &&
c != EOF )
; /* eat up text of comment */
if ( c == '*' )
{
while ( (c = input()) == '*' )
while ( (c = yyinput()) == '*' )
;
if ( c == '/' )
break; /* found the end */
@ -1445,13 +1445,6 @@ example, the following is one way to eat up C comments:
@end verbatim
@end example
@cindex input(), and C++
@cindex yyinput()
(Note that if the scanner is compiled using @code{C++}, then
@code{input()} is instead referred to as @b{yyinput()}, in order to
avoid a name clash with the @code{C++} stream by the name of
@code{input}.)
@cindex flushing the internal buffer
@cindex YY_FLUSH_BUFFER
@code{YY_FLUSH_BUFFER;} flushes the scanner's internal buffer so that
@ -4607,7 +4600,8 @@ a per-scanner (single global variable) basis.
@code{yylineno} is not part of the POSIX specification.
@item
The @code{input()} routine is not redefinable, though it may be called
The @code{input()} routine (which has become @code{yyinput()} in modern
Flex) is not redefinable, though it may be called
to read characters following whatever has been matched by a rule. If
@code{input()} encounters an end-of-file the normal @code{yywrap()}
processing is done. A ``real'' end-of-file is returned by
@ -5439,7 +5433,7 @@ other characters. Dynamic resizing of the input buffer is slow, as it
entails rescanning all the text matched so far by the current (generally
huge) token. Due to both buffering of input and read-ahead, you cannot
intermix calls to @file{<stdio.h>} routines, such as, @b{getchar()},
with @code{flex} rules and expect it to work. Call @code{input()}
with @code{flex} rules and expect it to work. Call @code{yyinput()}
instead. The total table entries listed by the @samp{-v} flag excludes
the number of table entries needed to determine what rule has been
matched. The number of entries is equal to the number of DFA states if
@ -6235,7 +6229,7 @@ example,
@end example
(You need to be careful to update your bookkeeping if you use @code{yymore(}),
@code{yyless()}, @code{unput()}, or @code{input()}.)
@code{yyless()}, @code{unput()}, or @code{yyinput()}.)
@node How do I use my own I/O classes in a C++ scanner?
@section How do I use my own I/O classes in a C++ scanner?
@ -8806,6 +8800,10 @@ YYSTART: Replaced by yystart()
@item
YY_AT_BOL: Replaced by yy_at_bol()
@item
input(): Replaced by yyinput(). This function was already yyinput()
in the C++ back end.
@end itemize
Flex also provides @code{YYSTATE} as an alias for @code{yystart()}

28
src/cpp-flex.skl
View File

@ -1424,18 +1424,17 @@ static void yy_flex_strncpy ( char *, const char *, int M4_YY_PROTO_LAST_ARG);
static int yy_flex_strlen ( const char * M4_YY_PROTO_LAST_ARG);
#endif
m4_ifdef([[M4_MODE_NO_INPUT]], [[#define YY_NO_INPUT 1]])
m4_ifdef([[M4_MODE_NO_YYINPUT]], [[#define YY_NO_YYINPUT 1]])
#ifndef YY_NO_INPUT
%if-c-only Standard (non-C++) definition
#ifndef YY_NO_YYINPUT
//%if-c-only Standard (non-C++) definition
%not-for-header
#ifdef __cplusplus
static int yyinput ( M4_YY_PROTO_ONLY_ARG );
#else
static int input ( M4_YY_PROTO_ONLY_ARG );
#ifndef __cplusplus
#define input yyinput
#endif
%ok-for-header
%endif
//%endif
#endif
@ -2720,13 +2719,8 @@ m4_ifdef( [[M4_MODE_YYLINENO]],
#endif
%if-c-only
#ifndef YY_NO_INPUT
#ifdef __cplusplus
static int yyinput (M4_YY_DEF_ONLY_ARG)
#else
static int input (M4_YY_DEF_ONLY_ARG)
#endif
#ifndef YY_NO_YYINPUT
int yyinput (M4_YY_DEF_ONLY_ARG)
%endif
%if-c++-only
int yyFlexLexer::yyinput()
@ -2774,11 +2768,7 @@ int yyFlexLexer::yyinput()
if ( ! YY_G(yy_did_buffer_switch_on_eof) ) {
YY_NEW_FILE;
}
#ifdef __cplusplus
return yyinput(M4_YY_CALL_ONLY_ARG);
#else
return input(M4_YY_CALL_ONLY_ARG);
#endif
case EOB_ACT_CONTINUE_SCAN:
YY_G(yy_c_buf_p) = YY_G(yytext_ptr) + offset;
@ -2810,7 +2800,7 @@ m4_ifdef([[M4_MODE_YYLINENO]], [[
return c;
}
%if-c-only
#endif /* ifndef YY_NO_INPUT */
#endif /* ifndef YY_NO_YYINPUT */
%endif
/** Immediately switch to a different input stream.

2
src/flexdef.h
View File

@ -338,7 +338,7 @@ struct ctrl_bundle_t {
bool never_interactive; // always use buffered input, don't check for tty.
bool lex_compat; // (-l), maximize compatibility with AT&T lex
bool long_align; // (-Ca flag), favor long-word alignment for speed
bool no_input; // Suppress use of imnput()
bool no_yyinput; // suppress use of yyinput()
bool no_unistd; // suppress inclusion of unistd.h
bool posix_compat; // (-X) maximize compatibility with POSIX lex
char *prefix; // prefix for externally visible names, default "yy"

5
src/main.c
View File

@ -1585,8 +1585,8 @@ void readin (void)
if (ctrl.prefix != NULL)
visible_define_str ( "M4_MODE_PREFIX", ctrl.prefix);
if (ctrl.no_input)
visible_define("M4_MODE_NO_INPUT");
if (ctrl.no_yyinput)
visible_define("M4_MODE_NO_YYINPUT");
if (ctrl.no_yy_push_state)
visible_define("M4_YY_NO_PUSH_STATE");
@ -1789,4 +1789,3 @@ void usage (void)
backing_name, "flex", outfile_path, "flex");
}

5
src/scan.l
View File

@ -384,7 +384,8 @@ M4QEND "]""]"
ctrl.useecs = ctrl.usemecs = false;
ctrl.use_read = ctrl.fulltbl = true;
}
input ctrl.no_input = ! option_sense;
input ctrl.no_yyinput = ! option_sense;
yyinput ctrl.no_yyinput = ! option_sense;
interactive ctrl.interactive = (trit)option_sense;
lex-compat ctrl.posix_compat = option_sense;
posix-compat ctrl.posix_compat = option_sense;
@ -659,7 +660,7 @@ M4QEND "]""]"
*/
&& (cclval = ccllookup( nmstr )) != 0 )
{
if ( input() != ']' )
if ( yyinput() != ']' )
synerr( _( "bad character class" ) );
yylval = cclval;

2
tests/yyextra.l
View File

@ -48,7 +48,7 @@ static void append_char (char c, yyscan_t scanner );
%}
%option 8bit prefix="test"
%option nounput nomain noyywrap nodefault noinput
%option nounput nomain noyywrap nodefault noyyinput
%option warn
%option reentrant