OSSP CVS Repository

ossp-pkg/cfg/cfg_syn_scan.l 1.1

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%{
/*
**  OSSP cfg - Configuration Parsing
**  Copyright (c) 1999-2002 Ralf S. Engelschall <rse@engelschall.com>
**  Copyright (c) 1999-2002 The OSSP Project (http://www.ossp.org/)
**  Copyright (c) 2001-2002 Cable & Wireless Deutschland (http://www.cw.com/de/)
**
**  This file is part of OSSP cfg, a configuration parsing
**  library which can be found at http://www.ossp.org/pkg/lib/cfg/.
**
**  Permission to use, copy, modify, and distribute this software for
**  any purpose with or without fee is hereby granted, provided that
**  the above copyright notice and this permission notice appear in all
**  copies.
**
**  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
**  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
**  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
**  IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
**  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
**  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
**  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
**  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
**  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
**  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
**  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
**  SUCH DAMAGE.
**
**  cfg_syn_scan.l: regular grammar specification for GNU Flex
**
**  ATTENTION: This requires GNU Flex 2.5.6 or newer!
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "cfg.h"
#include "cfg_syn.h"
#include "cfg_syn_parse.h"

/* how to find our own context */
#define CTX ((cfg_syn_ctx_t *)yyget_extra(yy_globals))

/* provide own input handling */
#define YY_NO_UNPUT 1
#undef  YY_INPUT
#define YY_INPUT(buf,result,max_size) (result = yyinput(CTX, buf, max_size))
static int yyinput(cfg_syn_ctx_t *ctx, char *buf, int max_size);

/* location tracking */
#define YY_USER_INIT \
    yylloc->first = 0; \
    yylloc->last  = 0;
#define YY_USER_ACTION \
    yylloc->first = yylloc->last; \
    yylloc->last += yyleng;
#define YY_USER_ACTION_ROLLBACK \
    yylloc->last = yylloc->first
%}

/* scanner options */
%pointer
%option stack
%option reentrant-bison
%option never-interactive
%option noyywrap

/* scanner states */
%x SS_DQ
%x SS_SQ
%x SS_CO_C

%%

    /* local variables */
    char  caStr[1024];
    char *cpStr = NULL;

    /* whitespaces */
[ \t\n]+ {
    /* no-op */
}

    /* C-style block comment */
"/*" {
    BEGIN(SS_CO_C);
}
<SS_CO_C>"*/" {
    BEGIN(INITIAL);
}
<SS_CO_C>(.|\n) {
    /* no-op */
}

    /* C++-style EOL comment */
"//"[^\n]* {
    /* no-op */
}

    /* Shell-style EOL comment */
"#"[^\n]* {
    /* no-op */
}

    /* double-quoted word ("...") */
\" {
    cpStr = caStr;
    BEGIN(SS_DQ);
}
<SS_DQ>\" {
    *cpStr = '\0';
    yylval->cpString = strdup(caStr);
    BEGIN(INITIAL);
    return T_STRING;
}
<SS_DQ>\\[0-7]{1,3} {
    unsigned int result;
    (void)sscanf(yytext+1, "%o", &result);
    if (result > 0xff) {
        cfg_syn_error(CTX, CFG_ERR_SYN, yylloc, "escape sequence out of bound");
        return 0;
    }
    *cpStr++ = result;
}
<SS_DQ>\\x[0-9a-fA-F]{2} {
    unsigned int result;
    (void)sscanf(yytext+1, "%x", &result);
    if (result > 0xff) {
        cfg_syn_error(CTX, CFG_ERR_SYN, yylloc, "escape sequence out of bound");
        return 0;
    }
    *cpStr++ = result;
}
<SS_DQ>\\n { *cpStr++ = '\n'; }
<SS_DQ>\\r { *cpStr++ = '\r'; }
<SS_DQ>\\t { *cpStr++ = '\t'; }
<SS_DQ>\\b { *cpStr++ = '\b'; }
<SS_DQ>\\f { *cpStr++ = '\f'; }
<SS_DQ>\\(.|\n) {
    *cpStr++ = yytext[1];
}
<SS_DQ>[^\\\"]+ {
    char *cp = yytext;
    while (*cp != '\0')
        *cpStr++ = *cp++;
}
<SS_DQ>(.|\n) {
    *cpStr++ = yytext[1];
}

    /* single-quoted word ('...') */
\' {
    cpStr = caStr;
    BEGIN(SS_SQ);
}
<SS_SQ>\' {
    *cpStr = '\0';
    yylval->cpString = strdup(caStr);
    BEGIN(INITIAL);
    return T_STRING;
}
<SS_SQ>\\(.|\n) {
    *cpStr++ = yytext[1];
}
<SS_SQ>[^\\\']+ {
    char *cp = yytext;
    while (*cp != '\0')
        *cpStr++ = *cp++;
}
<SS_SQ>(.|\n) {
    *cpStr++ = yytext[1];
}

    /* plain text word */
[^ \t\n;{}"']+ {
    yylval->cpString = strdup(yytext);
    return T_STRING;
}

   /* special tokens */
";" { return T_SEP; }
"{" { return T_OPEN; }
"}" { return T_CLOSE; }

   /* anything else is returned as is... */
.|\n {
    return yytext[0];
}

%%

/* external scanner state transitions */
void cfg_syn_scan_push(cfg_syn_ctx_t *ctx, const char *state);
void cfg_syn_scan_push(cfg_syn_ctx_t *ctx, const char *state)
{
    if (strcmp(state, "SS_SQ") == 0)
        yy_push_state(SS_SQ, ctx->yyscan);
}
void cfg_syn_scan_pop(cfg_syn_ctx_t *ctx);
void cfg_syn_scan_pop(cfg_syn_ctx_t *ctx)
{
    yy_pop_state(ctx->yyscan);
}

/* buffer-based input routine */
static int yyinput(cfg_syn_ctx_t *ctx, char *buf, int max_size)
{
    int n;

    n = (ctx->inputbuf + ctx->inputlen - ctx->inputptr);
    if (n > max_size)
        n = max_size;
    if (n <= 0)
        return YY_NULL;
    memcpy(buf, ctx->inputptr, n);
    ctx->inputptr += n;
    return n;
}

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