postgresql/contrib/cube/cubescan.l
Tom Lane fa96a5e15b Add %option nodefault to all our flex lexers. Fix a couple of rule gaps
exposed thereby.  AFAICT these would not lead to any worse problems than
junk emitted on the backend's stdout, but we should have the option to
catch possible worse errors in future.
2004-02-24 22:06:32 +00:00

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%{
/*
** A scanner for EMP-style numeric ranges
*/
#include "postgres.h"
/* No reason to constrain amount of data slurped */
#define YY_READ_BUF_SIZE 16777216
/* Avoid exit() on fatal scanner errors (a bit ugly -- see yy_fatal_error) */
#define fprintf(file, fmt, msg) ereport(ERROR, (errmsg_internal("%s", msg)))
/* Handles to the buffer that the lexer uses internally */
static YY_BUFFER_STATE scanbufhandle;
/* this is now declared in cubeparse.y: */
/* static char *scanbuf; */
/* static int scanbuflen; */
/* flex 2.5.4 doesn't bother with a decl for this */
int cube_yylex(void);
void cube_scanner_init(const char *str);
void cube_scanner_finish(void);
%}
%option 8bit
%option never-interactive
%option nodefault
%option nounput
%option noyywrap
%option prefix="cube_yy"
n [0-9]+
integer [+-]?{n}
real [+-]?({n}\.{n}?|\.{n})
float ({integer}|{real})([eE]{integer})?
%%
{float} yylval = yytext; return FLOAT;
\[ yylval = "("; return O_BRACKET;
\] yylval = ")"; return C_BRACKET;
\( yylval = "("; return O_PAREN;
\) yylval = ")"; return C_PAREN;
\, yylval = ")"; return COMMA;
[ \t\n\r\f]+ /* discard spaces */
. return yytext[0]; /* alert parser of the garbage */
%%
void
yyerror(const char *message)
{
if (*yytext == YY_END_OF_BUFFER_CHAR)
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("bad cube representation"),
/* translator: %s is typically "syntax error" */
errdetail("%s at end of input", message)));
}
else
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("bad cube representation"),
/* translator: first %s is typically "syntax error" */
errdetail("%s at or near \"%s\"", message, yytext)));
}
}
/*
* Called before any actual parsing is done
*/
void
cube_scanner_init(const char *str)
{
Size slen = strlen(str);
/*
* Might be left over after ereport()
*/
if (YY_CURRENT_BUFFER)
yy_delete_buffer(YY_CURRENT_BUFFER);
/*
* Make a scan buffer with special termination needed by flex.
*/
scanbuflen = slen;
scanbuf = palloc(slen + 2);
memcpy(scanbuf, str, slen);
scanbuf[slen] = scanbuf[slen + 1] = YY_END_OF_BUFFER_CHAR;
scanbufhandle = yy_scan_buffer(scanbuf, slen + 2);
BEGIN(INITIAL);
}
/*
* Called after parsing is done to clean up after cube_scanner_init()
*/
void
cube_scanner_finish(void)
{
yy_delete_buffer(scanbufhandle);
pfree(scanbuf);
}