tcc.c

Tiny C&C++,看看吧,也许用的着

        q++;
    }
    if (ptr)
        *ptr = p;
    return 1;
}

/* memory management */
#ifdef MEM_DEBUG
int mem_cur_size;
int mem_max_size;
#endif

static inline void tcc_free(void *ptr)
{
#ifdef MEM_DEBUG
    mem_cur_size -= malloc_usable_size(ptr);
#endif
    free(ptr);
}

static void *tcc_malloc(unsigned long size)
{
    void *ptr;
    ptr = malloc(size);
    if (!ptr && size)
        error("memory full");
#ifdef MEM_DEBUG
    mem_cur_size += malloc_usable_size(ptr);
    if (mem_cur_size > mem_max_size)
        mem_max_size = mem_cur_size;
#endif
    return ptr;
}

static void *tcc_mallocz(unsigned long size)
{
    void *ptr;
    ptr = tcc_malloc(size);
    memset(ptr, 0, size);
    return ptr;
}

static inline void *tcc_realloc(void *ptr, unsigned long size)
{
    void *ptr1;
#ifdef MEM_DEBUG
    mem_cur_size -= malloc_usable_size(ptr);
#endif
    ptr1 = realloc(ptr, size);
#ifdef MEM_DEBUG
    /* NOTE: count not correct if alloc error, but not critical */
    mem_cur_size += malloc_usable_size(ptr1);
    if (mem_cur_size > mem_max_size)
        mem_max_size = mem_cur_size;
#endif
    return ptr1;
}

static char *tcc_strdup(const char *str)
{
    char *ptr;
    ptr = tcc_malloc(strlen(str) + 1);
    strcpy(ptr, str);
    return ptr;
}

#define free(p) use_tcc_free(p)
#define malloc(s) use_tcc_malloc(s)
#define realloc(p, s) use_tcc_realloc(p, s)

static void dynarray_add(void ***ptab, int *nb_ptr, void *data)
{
    int nb, nb_alloc;
    void **pp;
    
    nb = *nb_ptr;
    pp = *ptab;
    /* every power of two we double array size */
    if ((nb & (nb - 1)) == 0) {
        if (!nb)
            nb_alloc = 1;
        else
            nb_alloc = nb * 2;
        pp = tcc_realloc(pp, nb_alloc * sizeof(void *));
        if (!pp)
            error("memory full");
        *ptab = pp;
    }
    pp[nb++] = data;
    *nb_ptr = nb;
}

/* symbol allocator */
static Sym *__sym_malloc(void)
{
    Sym *sym_pool, *sym, *last_sym;
    int i;

    sym_pool = tcc_malloc(SYM_POOL_NB * sizeof(Sym));

    last_sym = sym_free_first;
    sym = sym_pool;
    for(i = 0; i < SYM_POOL_NB; i++) {
        sym->next = last_sym;
        last_sym = sym;
        sym++;
    }
    sym_free_first = last_sym;
    return last_sym;
}

static inline Sym *sym_malloc(void)
{
    Sym *sym;
    sym = sym_free_first;
    if (!sym)
        sym = __sym_malloc();
    sym_free_first = sym->next;
    return sym;
}

static inline void sym_free(Sym *sym)
{
    sym->next = sym_free_first;
    sym_free_first = sym;
}

Section *new_section(TCCState *s1, const char *name, int sh_type, int sh_flags)
{
    Section *sec;

    sec = tcc_mallocz(sizeof(Section) + strlen(name));
    strcpy(sec->name, name);
    sec->sh_type = sh_type;
    sec->sh_flags = sh_flags;
    switch(sh_type) {
    case SHT_HASH:
    case SHT_REL:
    case SHT_DYNSYM:
    case SHT_SYMTAB:
    case SHT_DYNAMIC:
        sec->sh_addralign = 4;
        break;
    case SHT_STRTAB:
        sec->sh_addralign = 1;
        break;
    default:
        sec->sh_addralign = 32; /* default conservative alignment */
        break;
    }

    /* only add section if not private */
    if (!(sh_flags & SHF_PRIVATE)) {
        sec->sh_num = s1->nb_sections;
        dynarray_add((void ***)&s1->sections, &s1->nb_sections, sec);
    }
    return sec;
}

static void free_section(Section *s)
{
    tcc_free(s->data);
    tcc_free(s);
}

/* realloc section and set its content to zero */
static void section_realloc(Section *sec, unsigned long new_size)
{
    unsigned long size;
    unsigned char *data;
    
    size = sec->data_allocated;
    if (size == 0)
        size = 1;
    while (size < new_size)
        size = size * 2;
    data = tcc_realloc(sec->data, size);
    if (!data)
        error("memory full");
    memset(data + sec->data_allocated, 0, size - sec->data_allocated);
    sec->data = data;
    sec->data_allocated = size;
}

/* reserve at least 'size' bytes in section 'sec' from
   sec->data_offset. */
static void *section_ptr_add(Section *sec, unsigned long size)
{
    unsigned long offset, offset1;

    offset = sec->data_offset;
    offset1 = offset + size;
    if (offset1 > sec->data_allocated)
        section_realloc(sec, offset1);
    sec->data_offset = offset1;
    return sec->data + offset;
}

/* return a reference to a section, and create it if it does not
   exists */
Section *find_section(TCCState *s1, const char *name)
{
    Section *sec;
    int i;
    for(i = 1; i < s1->nb_sections; i++) {
        sec = s1->sections[i];
        if (!strcmp(name, sec->name)) 
            return sec;
    }
    /* sections are created as PROGBITS */
    return new_section(s1, name, SHT_PROGBITS, SHF_ALLOC);
}

#define SECTION_ABS ((void *)1)

/* update sym->c so that it points to an external symbol in section
   'section' with value 'value' */
static void put_extern_sym(Sym *sym, Section *section, 
                           unsigned long value, unsigned long size)
{
    int sym_type, sym_bind, sh_num, info;
    Elf32_Sym *esym;
    const char *name;

    if (section == NULL)
        sh_num = SHN_UNDEF;
    else if (section == SECTION_ABS) 
        sh_num = SHN_ABS;
    else
        sh_num = section->sh_num;
    if (!sym->c) {
        if ((sym->type.t & VT_BTYPE) == VT_FUNC)
            sym_type = STT_FUNC;
        else
            sym_type = STT_OBJECT;
        if (sym->type.t & VT_STATIC)
            sym_bind = STB_LOCAL;
        else
            sym_bind = STB_GLOBAL;
        
        name = get_tok_str(sym->v, NULL);
#ifdef CONFIG_TCC_BCHECK
        if (do_bounds_check) {
            char buf[32];

            /* XXX: avoid doing that for statics ? */
            /* if bound checking is activated, we change some function
               names by adding the "__bound" prefix */
            switch(sym->v) {
#if 0
            /* XXX: we rely only on malloc hooks */
            case TOK_malloc: 
            case TOK_free: 
            case TOK_realloc: 
            case TOK_memalign: 
            case TOK_calloc: 
#endif
            case TOK_memcpy: 
            case TOK_memmove:
            case TOK_memset:
            case TOK_strlen:
            case TOK_strcpy:
                strcpy(buf, "__bound_");
                strcat(buf, name);
                name = buf;
                break;
            }
        }
#endif
        info = ELF32_ST_INFO(sym_bind, sym_type);
        sym->c = add_elf_sym(symtab_section, value, size, info, sh_num, name);
    } else {
        esym = &((Elf32_Sym *)symtab_section->data)[sym->c];
        esym->st_value = value;
        esym->st_size = size;
        esym->st_shndx = sh_num;
    }
}

/* add a new relocation entry to symbol 'sym' in section 's' */
static void greloc(Section *s, Sym *sym, unsigned long offset, int type)
{
    if (!sym->c) 
        put_extern_sym(sym, NULL, 0, 0);
    /* now we can add ELF relocation info */
    put_elf_reloc(symtab_section, s, offset, type, sym->c);
}

static inline int isid(int c)
{
    return (c >= 'a' && c <= 'z') ||
        (c >= 'A' && c <= 'Z') ||
        c == '_';
}

static inline int isnum(int c)
{
    return c >= '0' && c <= '9';
}

static inline int isoct(int c)
{
    return c >= '0' && c <= '7';
}

static inline int toup(int c)
{
    if (c >= 'a' && c <= 'z')
        return c - 'a' + 'A';
    else
        return c;
}

static void strcat_vprintf(char *buf, int buf_size, const char *fmt, va_list ap)
{
    int len;
    len = strlen(buf);
    vsnprintf(buf + len, buf_size - len, fmt, ap);
}

static void strcat_printf(char *buf, int buf_size, const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    strcat_vprintf(buf, buf_size, fmt, ap);
    va_end(ap);
}

void error1(TCCState *s1, int is_warning, const char *fmt, va_list ap)
{
    char buf[2048];
    BufferedFile **f;
    
    buf[0] = '\0';
    if (file) {
        for(f = s1->include_stack; f < s1->include_stack_ptr; f++)
            strcat_printf(buf, sizeof(buf), "In file included from %s:%d:\n", 
                          (*f)->filename, (*f)->line_num);
        if (file->line_num > 0) {
            strcat_printf(buf, sizeof(buf), 
                          "%s:%d: ", file->filename, file->line_num);
        } else {
            strcat_printf(buf, sizeof(buf),
                          "%s: ", file->filename);
        }
    } else {
        strcat_printf(buf, sizeof(buf),
                      "tcc: ");
    }
    if (is_warning)
        strcat_printf(buf, sizeof(buf), "warning: ");
    strcat_vprintf(buf, sizeof(buf), fmt, ap);

    if (!s1->error_func) {
        /* default case: stderr */
        fprintf(stderr, "%s\n", buf);
    } else {
        s1->error_func(s1->error_opaque, buf);
    }
    if (!is_warning || s1->warn_error)
        s1->nb_errors++;
}

#ifdef LIBTCC
void tcc_set_error_func(TCCState *s, void *error_opaque,
                        void (*error_func)(void *opaque, const char *msg))
{
    s->error_opaque = error_opaque;
    s->error_func = error_func;
}
#endif

/* error without aborting current compilation */
void error_noabort(const char *fmt, ...)
{
    TCCState *s1 = tcc_state;
    va_list ap;

    va_start(ap, fmt);
    error1(s1, 0, fmt, ap);
    va_end(ap);
}

void error(const char *fmt, ...)
{
    TCCState *s1 = tcc_state;
    va_list ap;

    va_start(ap, fmt);
    error1(s1, 0, fmt, ap);
    va_end(ap);
    /* better than nothing: in some cases, we accept to handle errors */
    if (s1->error_set_jmp_enabled) {
        longjmp(s1->error_jmp_buf, 1);
    } else {
        /* XXX: eliminate this someday */
        exit(1);
    }
}

void expect(const char *msg)
{
    error("%s expected", msg);
}

void warning(const char *fmt, ...)
{
    TCCState *s1 = tcc_state;
    va_list ap;

    if (s1->warn_none)
        return;

    va_start(ap, fmt);
    error1(s1, 1, fmt, ap);
    va_end(ap);
}

void skip(int c)
{
    if (tok != c)
        error("'%c' expected", c);
    next();
}

static void test_lvalue(void)
{
    if (!(vtop->r & VT_LVAL))
        expect("lvalue");
}

/* allocate a new token */
static TokenSym *tok_alloc_new(TokenSym **pts, const char *str, int len)
{
    TokenSym *ts, **ptable;
    int i;

    if (tok_ident >= SYM_FIRST_ANOM) 
        error("memory full");

    /* expand token table if needed */
    i = tok_ident - TOK_IDENT;
    if ((i % TOK_ALLOC_INCR) == 0) {
        ptable = tcc_realloc(table_ident, (i + TOK_ALLOC_INCR) * sizeof(TokenSym *));
        if (!ptable)
            error("memory full");
        table_ident = ptable;
    }

    ts = tcc_malloc(sizeof(TokenSym) + len);
    table_ident[i] = ts;
    ts->tok = tok_ident++;
    ts->sym_define = NULL;
    ts->sym_label = NULL;
    ts->sym_struct = NULL;
    ts->sym_identifier = NULL;
    ts->len = len;
    ts->hash_next = NULL;
    memcpy(ts->str, str, len);
    ts->str[len] = '\0';
    *pts = ts;
    return ts;
}

#define TOK_HASH_INIT 1
#define TOK_HASH_FUNC(h, c) ((h) * 263 + (c))

/* find a token and add it if not found */
static TokenSym *tok_alloc(const char *str, int len)
{
    TokenSym *ts, **pts;
    int i;
    unsigned int h;
    
    h = TOK_HASH_INIT;
    for(i=0;i<len;i++)
        h = TOK_HASH_FUNC(h, ((unsigned char *)str)[i]);
    h &= (TOK_HASH_SIZE - 1);

    pts = &hash_ident[h];
    for(;;) {
        ts = *pts;
        if (!ts)