tcc.c

Tiny C&C++,看看吧,也许用的着

            break;
        if (ts->len == len && !memcmp(ts->str, str, len))
            return ts;
        pts = &(ts->hash_next);
    }
    return tok_alloc_new(pts, str, len);
}

/* CString handling */

static void cstr_realloc(CString *cstr, int new_size)
{
    int size;
    void *data;

    size = cstr->size_allocated;
    if (size == 0)
        size = 8; /* no need to allocate a too small first string */
    while (size < new_size)
        size = size * 2;
    data = tcc_realloc(cstr->data_allocated, size);
    if (!data)
        error("memory full");
    cstr->data_allocated = data;
    cstr->size_allocated = size;
    cstr->data = data;
}

/* add a byte */
static inline void cstr_ccat(CString *cstr, int ch)
{
    int size;
    size = cstr->size + 1;
    if (size > cstr->size_allocated)
        cstr_realloc(cstr, size);
    ((unsigned char *)cstr->data)[size - 1] = ch;
    cstr->size = size;
}

static void cstr_cat(CString *cstr, const char *str)
{
    int c;
    for(;;) {
        c = *str;
        if (c == '\0')
            break;
        cstr_ccat(cstr, c);
        str++;
    }
}

/* add a wide char */
static void cstr_wccat(CString *cstr, int ch)
{
    int size;
    size = cstr->size + sizeof(int);
    if (size > cstr->size_allocated)
        cstr_realloc(cstr, size);
    *(int *)(((unsigned char *)cstr->data) + size - sizeof(int)) = ch;
    cstr->size = size;
}

static void cstr_new(CString *cstr)
{
    memset(cstr, 0, sizeof(CString));
}

/* free string and reset it to NULL */
static void cstr_free(CString *cstr)
{
    tcc_free(cstr->data_allocated);
    cstr_new(cstr);
}

#define cstr_reset(cstr) cstr_free(cstr)

/* XXX: unicode ? */
static void add_char(CString *cstr, int c)
{
    if (c == '\'' || c == '\"' || c == '\\') {
        /* XXX: could be more precise if char or string */
        cstr_ccat(cstr, '\\');
    }
    if (c >= 32 && c <= 126) {
        cstr_ccat(cstr, c);
    } else {
        cstr_ccat(cstr, '\\');
        if (c == '\n') {
            cstr_ccat(cstr, 'n');
        } else {
            cstr_ccat(cstr, '0' + ((c >> 6) & 7));
            cstr_ccat(cstr, '0' + ((c >> 3) & 7));
            cstr_ccat(cstr, '0' + (c & 7));
        }
    }
}

/* XXX: buffer overflow */
/* XXX: float tokens */
char *get_tok_str(int v, CValue *cv)
{
    static char buf[STRING_MAX_SIZE + 1];
    static CString cstr_buf;
    CString *cstr;
    unsigned char *q;
    char *p;
    int i, len;

    /* NOTE: to go faster, we give a fixed buffer for small strings */
    cstr_reset(&cstr_buf);
    cstr_buf.data = buf;
    cstr_buf.size_allocated = sizeof(buf);
    p = buf;

    switch(v) {
    case TOK_CINT:
    case TOK_CUINT:
        /* XXX: not quite exact, but only useful for testing */
        sprintf(p, "%u", cv->ui);
        break;
    case TOK_CLLONG:
    case TOK_CULLONG:
        /* XXX: not quite exact, but only useful for testing  */
        sprintf(p, "%Lu", cv->ull);
        break;
    case TOK_CCHAR:
    case TOK_LCHAR:
        cstr_ccat(&cstr_buf, '\'');
        add_char(&cstr_buf, cv->i);
        cstr_ccat(&cstr_buf, '\'');
        cstr_ccat(&cstr_buf, '\0');
        break;
    case TOK_PPNUM:
        cstr = cv->cstr;
        len = cstr->size - 1;
        for(i=0;i<len;i++)
            add_char(&cstr_buf, ((unsigned char *)cstr->data)[i]);
        cstr_ccat(&cstr_buf, '\0');
        break;
    case TOK_STR:
    case TOK_LSTR:
        cstr = cv->cstr;
        cstr_ccat(&cstr_buf, '\"');
        if (v == TOK_STR) {
            len = cstr->size - 1;
            for(i=0;i<len;i++)
                add_char(&cstr_buf, ((unsigned char *)cstr->data)[i]);
        } else {
            len = (cstr->size / sizeof(int)) - 1;
            for(i=0;i<len;i++)
                add_char(&cstr_buf, ((int *)cstr->data)[i]);
        }
        cstr_ccat(&cstr_buf, '\"');
        cstr_ccat(&cstr_buf, '\0');
        break;
    case TOK_LT:
        v = '<';
        goto addv;
    case TOK_GT:
        v = '>';
        goto addv;
    case TOK_A_SHL:
        return strcpy(p, "<<=");
    case TOK_A_SAR:
        return strcpy(p, ">>=");
    default:
        if (v < TOK_IDENT) {
            /* search in two bytes table */
            q = tok_two_chars;
            while (*q) {
                if (q[2] == v) {
                    *p++ = q[0];
                    *p++ = q[1];
                    *p = '\0';
                    return buf;
                }
                q += 3;
            }
        addv:
            *p++ = v;
            *p = '\0';
        } else if (v < tok_ident) {
            return table_ident[v - TOK_IDENT]->str;
        } else if (v >= SYM_FIRST_ANOM) {
            /* special name for anonymous symbol */
            sprintf(p, "L.%u", v - SYM_FIRST_ANOM);
        } else {
            /* should never happen */
            return NULL;
        }
        break;
    }
    return cstr_buf.data;
}

/* push, without hashing */
static Sym *sym_push2(Sym **ps, int v, int t, int c)
{
    Sym *s;
    s = sym_malloc();
    s->v = v;
    s->type.t = t;
    s->c = c;
    s->next = NULL;
    /* add in stack */
    s->prev = *ps;
    *ps = s;
    return s;
}

/* find a symbol and return its associated structure. 's' is the top
   of the symbol stack */
static Sym *sym_find2(Sym *s, int v)
{
    while (s) {
        if (s->v == v)
            return s;
        s = s->prev;
    }
    return NULL;
}

/* structure lookup */
static inline Sym *struct_find(int v)
{
    v -= TOK_IDENT;
    if ((unsigned)v >= (unsigned)(tok_ident - TOK_IDENT))
        return NULL;
    return table_ident[v]->sym_struct;
}

/* find an identifier */
static inline Sym *sym_find(int v)
{
    v -= TOK_IDENT;
    if ((unsigned)v >= (unsigned)(tok_ident - TOK_IDENT))
        return NULL;
    return table_ident[v]->sym_identifier;
}

/* push a given symbol on the symbol stack */
static Sym *sym_push(int v, CType *type, int r, int c)
{
    Sym *s, **ps;
    TokenSym *ts;

    if (local_stack)
        ps = &local_stack;
    else
        ps = &global_stack;
    s = sym_push2(ps, v, type->t, c);
    s->type.ref = type->ref;
    s->r = r;
    /* don't record fields or anonymous symbols */
    /* XXX: simplify */
    if (!(v & SYM_FIELD) && (v & ~SYM_STRUCT) < SYM_FIRST_ANOM) {
        /* record symbol in token array */
        ts = table_ident[(v & ~SYM_STRUCT) - TOK_IDENT];
        if (v & SYM_STRUCT)
            ps = &ts->sym_struct;
        else
            ps = &ts->sym_identifier;
        s->prev_tok = *ps;
        *ps = s;
    }
    return s;
}

/* push a global identifier */
static Sym *global_identifier_push(int v, int t, int c)
{
    Sym *s, **ps;
    s = sym_push2(&global_stack, v, t, c);
    /* don't record anonymous symbol */
    if (v < SYM_FIRST_ANOM) {
        ps = &table_ident[v - TOK_IDENT]->sym_identifier;
        /* modify the top most local identifier, so that
           sym_identifier will point to 's' when popped */
        while (*ps != NULL)
            ps = &(*ps)->prev_tok;
        s->prev_tok = NULL;
        *ps = s;
    }
    return s;
}

/* pop symbols until top reaches 'b' */
static void sym_pop(Sym **ptop, Sym *b)
{
    Sym *s, *ss, **ps;
    TokenSym *ts;
    int v;

    s = *ptop;
    while(s != b) {
        ss = s->prev;
        v = s->v;
        /* remove symbol in token array */
        /* XXX: simplify */
        if (!(v & SYM_FIELD) && (v & ~SYM_STRUCT) < SYM_FIRST_ANOM) {
            ts = table_ident[(v & ~SYM_STRUCT) - TOK_IDENT];
            if (v & SYM_STRUCT)
                ps = &ts->sym_struct;
            else
                ps = &ts->sym_identifier;
            *ps = s->prev_tok;
        }
        sym_free(s);
        s = ss;
    }
    *ptop = b;
}

/* I/O layer */

BufferedFile *tcc_open(TCCState *s1, const char *filename)
{
    int fd;
    BufferedFile *bf;

    fd = open(filename, O_RDONLY | O_BINARY);
    if (fd < 0)
        return NULL;
    bf = tcc_malloc(sizeof(BufferedFile));
    if (!bf) {
        close(fd);
        return NULL;
    }
    bf->fd = fd;
    bf->buf_ptr = bf->buffer;
    bf->buf_end = bf->buffer;
    bf->buffer[0] = CH_EOB; /* put eob symbol */
    pstrcpy(bf->filename, sizeof(bf->filename), filename);
    bf->line_num = 1;
    bf->ifndef_macro = 0;
    bf->ifdef_stack_ptr = s1->ifdef_stack_ptr;
    //    printf("opening '%s'\n", filename);
    return bf;
}

void tcc_close(BufferedFile *bf)
{
    total_lines += bf->line_num;
    close(bf->fd);
    tcc_free(bf);
}

/* fill input buffer and peek next char */
static int tcc_peekc_slow(BufferedFile *bf)
{
    int len;
    /* only tries to read if really end of buffer */
    if (bf->buf_ptr >= bf->buf_end) {
        if (bf->fd != -1) {
#if defined(PARSE_DEBUG)
            len = 8;
#else
            len = IO_BUF_SIZE;
#endif
            len = read(bf->fd, bf->buffer, len);
            if (len < 0)
                len = 0;
        } else {
            len = 0;
        }
        total_bytes += len;
        bf->buf_ptr = bf->buffer;
        bf->buf_end = bf->buffer + len;
        *bf->buf_end = CH_EOB;
    }
    if (bf->buf_ptr < bf->buf_end) {
        return bf->buf_ptr[0];
    } else {
        bf->buf_ptr = bf->buf_end;
        return CH_EOF;
    }
}

/* return the current character, handling end of block if necessary
   (but not stray) */
static int handle_eob(void)
{
    return tcc_peekc_slow(file);
}

/* read next char from current input file and handle end of input buffer */
static inline void inp(void)
{
    ch = *(++(file->buf_ptr));
    /* end of buffer/file handling */
    if (ch == CH_EOB)
        ch = handle_eob();
}

/* handle '\[\r]\n' */
static void handle_stray(void)
{
    while (ch == '\\') {
        inp();
        if (ch == '\n') {
            file->line_num++;
            inp();
        } else if (ch == '\r') {
            inp();
            if (ch != '\n')
                goto fail;
            file->line_num++;
            inp();
        } else {
        fail:
            error("stray '\\' in program");
        }
    }
}

/* skip the stray and handle the \\n case. Output an error if
   incorrect char after the stray */
static int handle_stray1(uint8_t *p)
{
    int c;

    if (p >= file->buf_end) {
        file->buf_ptr = p;
        c = handle_eob();
        p = file->buf_ptr;
        if (c == '\\')
            goto parse_stray;
    } else {
    parse_stray:
        file->buf_ptr = p;
        ch = *p;
        handle_stray();
        p = file->buf_ptr;
        c = *p;
    }
    return c;
}

/* handle just the EOB case, but not stray */
#define PEEKC_EOB(c, p)\
{\
    p++;\
    c = *p;\
    if (c == '\\') {\
        file->buf_ptr = p;\
        c = handle_eob();\
        p = file->buf_ptr;\
    }\
}

/* handle the complicated stray case */
#define PEEKC(c, p)\
{\
    p++;\
    c = *p;\
    if (c == '\\') {\
        c = handle_stray1(p);\
        p = file->buf_ptr;\
    }\
}

/* input with '\[\r]\n' handling. Note that this function cannot
   handle other characters after '\', so you cannot call it inside
   strings or comments */
static void minp(void)
{
    inp();
    if (ch == '\\') 
        handle_stray();
}


/* single line C++ comments */
static uint8_t *parse_line_comment(uint8_t *p)
{
    int c;

    p++;
    for(;;) {
        c = *p;
    redo:
        if (c == '\n' || c == CH_EOF) {
            break;
        } else if (c == '\\') {