tcc.c

Tiny C&C++,看看吧,也许用的着

            file->buf_ptr = p;
            c = handle_eob();
            p = file->buf_ptr;
            if (c == '\\') {
                PEEKC_EOB(c, p);
                if (c == '\n') {
                    file->line_num++;
                    PEEKC_EOB(c, p);
                } else if (c == '\r') {
                    PEEKC_EOB(c, p);
                    if (c == '\n') {
                        file->line_num++;
                        PEEKC_EOB(c, p);
                    }
                }
            } else {
                goto redo;
            }
        } else {
            p++;
        }
    }
    return p;
}

/* C comments */
static uint8_t *parse_comment(uint8_t *p)
{
    int c;
    
    p++;
    for(;;) {
        /* fast skip loop */
        for(;;) {
            c = *p;
            if (c == '\n' || c == '*' || c == '\\')
                break;
            p++;
            c = *p;
            if (c == '\n' || c == '*' || c == '\\')
                break;
            p++;
        }
        /* now we can handle all the cases */
        if (c == '\n') {
            file->line_num++;
            p++;
        } else if (c == '*') {
            p++;
            for(;;) {
                c = *p;
                if (c == '*') {
                    p++;
                } else if (c == '/') {
                    goto end_of_comment;
                } else if (c == '\\') {
                    file->buf_ptr = p;
                    c = handle_eob();
                    p = file->buf_ptr;
                    if (c == '\\') {
                        /* skip '\[\r]\n', otherwise just skip the stray */
                        while (c == '\\') {
                            PEEKC_EOB(c, p);
                            if (c == '\n') {
                                file->line_num++;
                                PEEKC_EOB(c, p);
                            } else if (c == '\r') {
                                PEEKC_EOB(c, p);
                                if (c == '\n') {
                                    file->line_num++;
                                    PEEKC_EOB(c, p);
                                }
                            } else {
                                goto after_star;
                            }
                        }
                    }
                } else {
                    break;
                }
            }
        after_star: ;
        } else {
            /* stray, eob or eof */
            file->buf_ptr = p;
            c = handle_eob();
            p = file->buf_ptr;
            if (c == CH_EOF) {
                error("unexpected end of file in comment");
            } else if (c == '\\') {
                p++;
            }
        }
    }
 end_of_comment:
    p++;
    return p;
}

#define cinp minp

/* space exlcuding newline */
static inline int is_space(int ch)
{
    return ch == ' ' || ch == '\t' || ch == '\v' || ch == '\f' || ch == '\r';
}

static inline void skip_spaces(void)
{
    while (is_space(ch))
        cinp();
}

/* parse a string without interpreting escapes */
static uint8_t *parse_pp_string(uint8_t *p,
                                int sep, CString *str)
{
    int c;
    p++;
    for(;;) {
        c = *p;
        if (c == sep) {
            break;
        } else if (c == '\\') {
            file->buf_ptr = p;
            c = handle_eob();
            p = file->buf_ptr;
            if (c == CH_EOF) {
            unterminated_string:
                /* XXX: indicate line number of start of string */
                error("missing terminating %c character", sep);
            } else if (c == '\\') {
                /* escape : just skip \[\r]\n */
                PEEKC_EOB(c, p);
                if (c == '\n') {
                    file->line_num++;
                    p++;
                } else if (c == '\r') {
                    PEEKC_EOB(c, p);
                    if (c != '\n')
                        expect("'\n' after '\r'");
                    file->line_num++;
                    p++;
                } else if (c == CH_EOF) {
                    goto unterminated_string;
                } else {
                    if (str) {
                        cstr_ccat(str, '\\');
                        cstr_ccat(str, c);
                    }
                    p++;
                }
            }
        } else if (c == '\n') {
            file->line_num++;
            goto add_char;
        } else if (c == '\r') {
            PEEKC_EOB(c, p);
            if (c != '\n') {
                if (str)
                    cstr_ccat(str, '\r');
            } else {
                file->line_num++;
                goto add_char;
            }
        } else {
        add_char:
            if (str)
                cstr_ccat(str, c);
            p++;
        }
    }
    p++;
    return p;
}

/* skip block of text until #else, #elif or #endif. skip also pairs of
   #if/#endif */
void preprocess_skip(void)
{
    int a, start_of_line, c;
    uint8_t *p;

    p = file->buf_ptr;
    start_of_line = 1;
    a = 0;
    for(;;) {
    redo_no_start:
        c = *p;
        switch(c) {
        case ' ':
        case '\t':
        case '\f':
        case '\v':
        case '\r':
            p++;
            goto redo_no_start;
        case '\n':
            start_of_line = 1;
            file->line_num++;
            p++;
            goto redo_no_start;
        case '\\':
            file->buf_ptr = p;
            c = handle_eob();
            if (c == CH_EOF) {
                expect("#endif");
            } else if (c == '\\') {
                /* XXX: incorrect: should not give an error */
                ch = file->buf_ptr[0];
                handle_stray();
            }
            p = file->buf_ptr;
            goto redo_no_start;
            /* skip strings */
        case '\"':
        case '\'':
            p = parse_pp_string(p, c, NULL);
            break;
            /* skip comments */
        case '/':
            file->buf_ptr = p;
            ch = *p;
            minp();
            p = file->buf_ptr;
            if (ch == '*') {
                p = parse_comment(p);
            } else if (ch == '/') {
                p = parse_line_comment(p);
            }
            break;

        case '#':
            p++;
            if (start_of_line) {
                file->buf_ptr = p;
                next_nomacro();
                p = file->buf_ptr;
                if (a == 0 && 
                    (tok == TOK_ELSE || tok == TOK_ELIF || tok == TOK_ENDIF))
                    goto the_end;
                if (tok == TOK_IF || tok == TOK_IFDEF || tok == TOK_IFNDEF)
                    a++;
                else if (tok == TOK_ENDIF)
                    a--;
            }
            break;
        default:
            p++;
            break;
        }
        start_of_line = 0;
    }
 the_end: ;
    file->buf_ptr = p;
}

/* ParseState handling */

/* XXX: currently, no include file info is stored. Thus, we cannot display
   accurate messages if the function or data definition spans multiple
   files */

/* save current parse state in 's' */
void save_parse_state(ParseState *s)
{
    s->line_num = file->line_num;
    s->macro_ptr = macro_ptr;
    s->tok = tok;
    s->tokc = tokc;
}

/* restore parse state from 's' */
void restore_parse_state(ParseState *s)
{
    file->line_num = s->line_num;
    macro_ptr = s->macro_ptr;
    tok = s->tok;
    tokc = s->tokc;
}

/* return the number of additional 'ints' necessary to store the
   token */
static inline int tok_ext_size(int t)
{
    switch(t) {
        /* 4 bytes */
    case TOK_CINT:
    case TOK_CUINT:
    case TOK_CCHAR:
    case TOK_LCHAR:
    case TOK_CFLOAT:
    case TOK_LINENUM:
        return 1;
    case TOK_STR:
    case TOK_LSTR:
    case TOK_PPNUM:
        error("unsupported token");
        return 1;
    case TOK_CDOUBLE:
    case TOK_CLLONG:
    case TOK_CULLONG:
        return 2;
    case TOK_CLDOUBLE:
        return LDOUBLE_SIZE / 4;
    default:
        return 0;
    }
}

/* token string handling */

static inline void tok_str_new(TokenString *s)
{
    s->str = NULL;
    s->len = 0;
    s->allocated_len = 0;
    s->last_line_num = -1;
}

static void tok_str_free(int *str)
{
    tcc_free(str);
}

static int *tok_str_realloc(TokenString *s)
{
    int *str, len;

    if (s->allocated_len == 0) {
        len = 8;
    } else {
        len = s->allocated_len * 2;
    }
    str = tcc_realloc(s->str, len * sizeof(int));
    if (!str)
        error("memory full");
    s->allocated_len = len;
    s->str = str;
    return str;
}

static void tok_str_add(TokenString *s, int t)
{
    int len, *str;

    len = s->len;
    str = s->str;
    if (len >= s->allocated_len)
        str = tok_str_realloc(s);
    str[len++] = t;
    s->len = len;
}

static void tok_str_add2(TokenString *s, int t, CValue *cv)
{
    int len, *str;

    len = s->len;
    str = s->str;

    /* allocate space for worst case */
    if (len + TOK_MAX_SIZE > s->allocated_len)
        str = tok_str_realloc(s);
    str[len++] = t;
    switch(t) {
    case TOK_CINT:
    case TOK_CUINT:
    case TOK_CCHAR:
    case TOK_LCHAR:
    case TOK_CFLOAT:
    case TOK_LINENUM:
        str[len++] = cv->tab[0];
        break;
    case TOK_PPNUM:
    case TOK_STR:
    case TOK_LSTR:
        {
            int nb_words;
            CString *cstr;

            nb_words = (sizeof(CString) + cv->cstr->size + 3) >> 2;
            while ((len + nb_words) > s->allocated_len)
                str = tok_str_realloc(s);
            cstr = (CString *)(str + len);
            cstr->data = NULL;
            cstr->size = cv->cstr->size;
            cstr->data_allocated = NULL;
            cstr->size_allocated = cstr->size;
            memcpy((char *)cstr + sizeof(CString), 
                   cv->cstr->data, cstr->size);
            len += nb_words;
        }
        break;
    case TOK_CDOUBLE:
    case TOK_CLLONG:
    case TOK_CULLONG:
#if LDOUBLE_SIZE == 8
    case TOK_CLDOUBLE:
#endif
        str[len++] = cv->tab[0];
        str[len++] = cv->tab[1];
        break;
#if LDOUBLE_SIZE == 12
    case TOK_CLDOUBLE:
        str[len++] = cv->tab[0];
        str[len++] = cv->tab[1];
        str[len++] = cv->tab[2];
#elif LDOUBLE_SIZE != 8
#error add long double size support
#endif
        break;
    default:
        break;
    }
    s->len = len;
}

/* add the current parse token in token string 's' */
static void tok_str_add_tok(TokenString *s)
{
    CValue cval;

    /* save line number info */
    if (file->line_num != s->last_line_num) {
        s->last_line_num = file->line_num;
        cval.i = s->last_line_num;
        tok_str_add2(s, TOK_LINENUM, &cval);
    }
    tok_str_add2(s, tok, &tokc);
}

#if LDOUBLE_SIZE == 12
#define LDOUBLE_GET(p, cv)                      \
        cv.tab[0] = p[0];                       \
        cv.tab[1] = p[1];                       \
        cv.tab[2] = p[2];
#elif LDOUBLE_SIZE == 8
#define LDOUBLE_GET(p, cv)                      \
        cv.tab[0] = p[0];                       \
        cv.tab[1] = p[1];
#else
#error add long double size support
#endif


/* get a token from an integer array and increment pointer
   accordingly. we code it as a macro to avoid pointer aliasing. */
#define TOK_GET(t, p, cv)                       \
{                                               \
    t = *p++;                                   \
    switch(t) {                                 \
    case TOK_CINT:                              \
    case TOK_CUINT:                             \
    case TOK_CCHAR:                             \
    case TOK_LCHAR:                             \
    case TOK_CFLOAT:                            \
    case TOK_LINENUM:                           \
        cv.tab[0] = *p++;                       \
        break;                                  \
    case TOK_STR:                               \
    case TOK_LSTR:                              \
    case TOK_PPNUM:                             \
        cv.cstr = (CString *)p;                 \
        cv.cstr->data = (char *)p + sizeof(CString);\
        p += (sizeof(CString) + cv.cstr->size + 3) >> 2;\
        break;                                  \
    case TOK_CDOUBLE:                           \
    case TOK_CLLONG:                            \
    case TOK_CULLONG:                           \
        cv.tab[0] = p[0];                       \
        cv.tab[1] = p[1];                       \
        p += 2;                                 \
        break;                                  \
    case TOK_CLDOUBLE:                          \
        LDOUBLE_GET(p, cv);                     \
        p += LDOUBLE_SIZE / 4;                  \
        break;                                  \
    default:                                    \
        break;                                  \
    }                                           \