path: root/wiretap/candump_parser.lemon

%include {

/* candump_parser.lemon
 *
 * Wiretap Library
 * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
 *
 * Support for candump log file format
 * Copyright (c) 2019 by Maksim Salau <maksim.salau@gmail.com>
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include <ws_diag_control.h>
#include <assert.h>
#include <string.h>
#include <wiretap/file_wrappers.h>
#include <wsutil/array.h>
#include "candump_priv.h"

extern void *CandumpParserAlloc(void *(*mallocProc)(size_t));
extern void CandumpParser(void *yyp, int yymajor, token_t yyminor, candump_state_t *state);
extern void CandumpParserFree(void *p, void (*freeProc)(void*));

#ifdef CANDUMP_DEBUG
extern void CandumpParserTrace(FILE *TraceFILE, char *zTracePrompt);
#endif

static void merge_msg_data(msg_data_t *dst, const msg_data_t *a, const msg_data_t *b)
{
    dst->length = a->length + b->length;
    memcpy(&dst->data[0], &a->data[0], a->length);
    memcpy(&dst->data[a->length], &b->data[0], b->length);
}

DIAG_OFF_LEMON()
} /* end of %include */

%code {
DIAG_ON_LEMON()
}

%name CandumpParser

%token_prefix TOKEN_

%token_type { token_t }

%token_destructor
{
    (void)state;
    (void)yypParser;
    (void)yypminor;
}

%extra_argument { candump_state_t* state }

%syntax_error
{
    (void)yypParser;
    (void)yyminor;

#ifdef CANDUMP_DEBUG
    const int n = array_length(yyTokenName);
    candump_debug_printf("%s: got token: %s\n", G_STRFUNC, yyTokenName[yymajor]);
    for (int i = 0; i < n; ++i) {
        int a = yy_find_shift_action((YYCODETYPE)i, yypParser->yytos->stateno);
        if (a < YYNSTATE + YYNRULE) {
            candump_debug_printf("%s: possible token: %s\n", G_STRFUNC, yyTokenName[i]);
        }
    }
#endif

    g_free(state->parse_error);
    state->parse_error = ws_strdup_printf("Syntax Error");
#ifdef CANDUMP_DEBUG
    candump_debug_printf("%s: Syntax Error\n", G_STRFUNC);
#endif
}

%parse_failure
{
    g_free(state->parse_error);
    state->parse_error = g_strdup("Parse Error");
#ifdef CANDUMP_DEBUG
    candump_debug_printf("%s: Parse Error\n", G_STRFUNC);
#endif
}

%type msg { msg_t }

%type timestamp { nstime_t }
%type id { uint32_t }
%type flags { uint8_t }

%type byte { uint8_t }
%type data_max_8 { msg_data_t }
%type data_max_64 { msg_data_t }
%type data0 { msg_data_t }
%type data1 { msg_data_t }
%type data2 { msg_data_t }
%type data3 { msg_data_t }
%type data4 { msg_data_t }
%type data5 { msg_data_t }
%type data6 { msg_data_t }
%type data7 { msg_data_t }
%type data8 { msg_data_t }
%type data12 { msg_data_t }
%type data16 { msg_data_t }
%type data20 { msg_data_t }
%type data24 { msg_data_t }
%type data32 { msg_data_t }
%type data48 { msg_data_t }
%type data64 { msg_data_t }

%start_symbol line

line ::= maybe_spaces msg(M) .
{
#ifdef CANDUMP_DEBUG
    candump_debug_printf("%s: read message\n", G_STRFUNC);
#endif

    state->msg          = M;
    state->is_msg_valid = true;
}

line ::= maybe_spaces .
{
#ifdef CANDUMP_DEBUG
    candump_debug_printf("%s: read empty line\n", G_STRFUNC);
#endif
}

maybe_spaces ::= maybe_spaces SPACE .
maybe_spaces ::= .

msg(M) ::= timestamp(T) SPACE ifname SPACE id(I) RTR(R) .
{
    M.ts          = T;
    M.is_fd       = false;
    M.id          = I | CAN_RTR_FLAG;
    M.data.length = (uint8_t)R.v0;

    memset(M.data.data, 0, sizeof(M.data.data));
}

msg(M) ::= timestamp(T) SPACE ifname SPACE id(I) data_max_8(D) .
{
    M.ts    = T;
    M.is_fd = false;
    M.id    = I;
    M.data  = D;
}

msg(M) ::= timestamp(T) SPACE ifname SPACE id(I) flags(F) data_max_64(D) .
{
    M.ts    = T;
    M.is_fd = true;
    M.id    = I;
    M.flags = F;
    M.data  = D;
}

timestamp(R) ::= TIMESTAMP(A) .
{
    R.secs  = (time_t)A.v0;
    R.nsecs = (int)A.v1 * 1000;
}

ifname ::= ifname any .
ifname ::= any .

any ::= UNKNOWN .
any ::= RTR .
any ::= STD_ID .
any ::= EXT_ID .
any ::= FLAGS .
any ::= TIMESTAMP .
any ::= BYTE .

id(R) ::= STD_ID(A) .
{
    R = (uint32_t)A.v0;
}

id(R) ::= EXT_ID(A) .
{
    R = (uint32_t)A.v0;

    if (!(R & CAN_ERR_FLAG))
        R |= CAN_EFF_FLAG;
}

flags(R) ::= FLAGS(A) .
{
    R = (uint8_t)A.v0;
}

data_max_8 ::= data0 .
data_max_8 ::= data1 .
data_max_8 ::= data2 .
data_max_8 ::= data3 .
data_max_8 ::= data4 .
data_max_8 ::= data5 .
data_max_8 ::= data6 .
data_max_8 ::= data7 .
data_max_8 ::= data8 .

data_max_64 ::= data_max_8 .
data_max_64 ::= data12 .
data_max_64 ::= data16 .
data_max_64 ::= data20 .
data_max_64 ::= data24 .
data_max_64 ::= data32 .
data_max_64 ::= data48 .
data_max_64 ::= data64 .

byte(R) ::= BYTE(A) .
{
    R = (uint8_t)A.v0;
}

data0(R) ::= .
{
    R.length = 0;
}

data1(R) ::= byte(A) .
{
    R.length  = 1;
    R.data[0] = A;
}

data2(R) ::= byte(A) byte(B) .
{
    R.length  = 2;
    R.data[0] = A;
    R.data[1] = B;
}

data3(R) ::= byte(A) byte(B) byte(C) .
{
    R.length  = 3;
    R.data[0] = A;
    R.data[1] = B;
    R.data[2] = C;
}

data4(R) ::= byte(A) byte(B) byte(C) byte(D) .
{
    R.length  = 4;
    R.data[0] = A;
    R.data[1] = B;
    R.data[2] = C;
    R.data[3] = D;
}

data5(R)  ::= data4(A)  data1(B) .  { merge_msg_data(&R, &A, &B); }
data6(R)  ::= data4(A)  data2(B) .  { merge_msg_data(&R, &A, &B); }
data7(R)  ::= data4(A)  data3(B) .  { merge_msg_data(&R, &A, &B); }
data8(R)  ::= data4(A)  data4(B) .  { merge_msg_data(&R, &A, &B); }
data12(R) ::= data8(A)  data4(B) .  { merge_msg_data(&R, &A, &B); }
data16(R) ::= data8(A)  data8(B) .  { merge_msg_data(&R, &A, &B); }
data20(R) ::= data16(A) data4(B) .  { merge_msg_data(&R, &A, &B); }
data24(R) ::= data16(A) data8(B) .  { merge_msg_data(&R, &A, &B); }
data32(R) ::= data16(A) data16(B) . { merge_msg_data(&R, &A, &B); }
data48(R) ::= data32(A) data16(B) . { merge_msg_data(&R, &A, &B); }
data64(R) ::= data32(A) data32(B) . { merge_msg_data(&R, &A, &B); }

%code {

#include "candump_scanner_lex.h"
#include "candump_parser.h"

bool
run_candump_parser(candump_state_t *state, int *err, char **err_info)
{
    int              lex_code;
    yyscan_t         scanner;
    void            *parser;

    state->err         = 0;
    state->err_info    = NULL;
    state->parse_error = NULL;

    if (candump_lex_init_extra(state, &scanner) != 0)
    {
        *err      = errno;
        *err_info = g_strdup(g_strerror(errno));

        return false;
    }

    parser = CandumpParserAlloc(g_malloc);

#ifdef CANDUMP_DEBUG
    CandumpParserTrace(stdout, "parser >> ");

    candump_debug_printf("%s: Starting parsing\n", G_STRFUNC);
#endif

    do
    {
        lex_code = candump_lex(scanner);

#ifdef CANDUMP_DEBUG
        if (lex_code)
            candump_debug_printf("%s: Feeding %s '%s'\n",
                            G_STRFUNC, yyTokenName[lex_code],
                            candump_get_text(scanner));
        else
            candump_debug_printf("%s: Feeding %s\n",
                            G_STRFUNC, yyTokenName[lex_code]);
#endif

        CandumpParser(parser, lex_code, state->token, state);

        if (state->err || state->err_info || state->parse_error)
            break;
    }
    while (lex_code);

#ifdef CANDUMP_DEBUG
    candump_debug_printf("%s: Done (%d)\n", G_STRFUNC, lex_code);
#endif

    CandumpParserFree(parser, g_free);
    candump_lex_destroy(scanner);

    if (state->err || state->err_info || state->parse_error)
    {
        if (state->err_info)
        {
            *err_info = state->err_info;
            g_free(state->parse_error);
        }
        else
        {
            *err_info = state->parse_error;
        }

        if (state->err)
            *err = state->err;
        else
            *err = WTAP_ERR_BAD_FILE;

        return false;
    }

    return true;
}

}