stabs.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

    /* ar<typeinfo_nodef>;<int>;<int>;<typeinfo> */

    PTS_ABORTIF(ptd, *ptd->ptr++ != 'r');
    /* FIXME: range type is lost, always assume int */
    PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &rdt) == -1);
    PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */
    PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &lo) == -1);
    PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */
    PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &hi) == -1);
    PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */

    PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &rdt) == -1);

    *adt = &symt_new_array(ptd->module, lo, hi, rdt)->symt;
    return 0;
}

static int stabs_pts_read_type_def(struct ParseTypedefData* ptd, const char* typename,
                                   struct symt** ret_dt)
{
    int			idx;
    long                sz = -1;
    struct symt*        new_dt = NULL; /* newly created data type */
    struct symt*        ref_dt;		   /* referenced data type (pointer...) */
    long		filenr1, subnr1, tmp;

    /* things are a bit complicated because of the way the typedefs are stored inside
     * the file, because addresses can change when realloc is done, so we must call
     * over and over stabs_find_ref() to keep the correct values around
     */
    PTS_ABORTIF(ptd, stabs_pts_read_type_reference(ptd, &filenr1, &subnr1) == -1);

    while (*ptd->ptr == '=')
    {
	ptd->ptr++;
	PTS_ABORTIF(ptd, new_dt != btNoType);

	/* first handle attribute if any */
	switch (*ptd->ptr)      
        {
	case '@':
	    if (*++ptd->ptr == 's')
            {
		ptd->ptr++;
		if (stabs_pts_read_number(ptd, &sz) == -1)
                {
		    ERR("Not an attribute... NIY\n");
		    ptd->ptr -= 2;
		    return -1;
		}
		PTS_ABORTIF(ptd, *ptd->ptr++ != ';');
	    }
	    break;
	}
	/* then the real definitions */
	switch (*ptd->ptr++)
        {
	case '*':
        case '&':
	    PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &ref_dt) == -1);
	    new_dt = &symt_new_pointer(ptd->module, ref_dt)->symt;
           break;
        case 'k': /* 'const' modifier */
        case 'B': /* 'volatile' modifier */
            /* just kinda ignore the modifier, I guess -gmt */
            PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, typename, &new_dt) == -1);
	    break;
	case '(':
	    ptd->ptr--;
            PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, typename, &new_dt) == -1);
	    break;
	case 'a':
	    PTS_ABORTIF(ptd, stabs_pts_read_array(ptd, &new_dt) == -1);
	    break;
	case 'r':
	    PTS_ABORTIF(ptd, stabs_pts_read_range(ptd, typename, &new_dt) == -1);
	    assert(!*stabs_find_ref(filenr1, subnr1));
	    *stabs_find_ref(filenr1, subnr1) = new_dt;
	    break;
	case 'f':
	    PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &ref_dt) == -1);
	    new_dt = &symt_new_function_signature(ptd->module, ref_dt)->symt;
	    break;
	case 'e':
	    new_dt = &symt_new_enum(ptd->module, typename)->symt;
	    PTS_ABORTIF(ptd, stabs_pts_read_enum(ptd, (struct symt_enum*)new_dt) == -1);
	    break;
	case 's':
	case 'u':
            {
                struct symt_udt*    udt;
                enum UdtKind kind = (ptd->ptr[-1] == 's') ? UdtStruct : UdtUnion;
                /* udt can have been already defined in a forward definition */
                udt = (struct symt_udt*)*stabs_find_ref(filenr1, subnr1);
                if (!udt)
                {
                    udt = symt_new_udt(ptd->module, typename, 0, kind);
                    /* we need to set it here, because a struct can hold a pointer
                     * to itself
                     */
                    new_dt = *stabs_find_ref(filenr1, subnr1) = &udt->symt;
                }
                else
                {
                    if (udt->symt.tag != SymTagUDT)
                    {
                        ERR("Forward declaration (%p/%s) is not an aggregate (%u)\n",
                            udt, symt_get_name(&udt->symt), udt->symt.tag);
                        return -1;
                    }
                    if (strcmp(udt->hash_elt.name, typename))
                        ERR("Forward declaration name mismatch %s <> %s\n",
                            udt->hash_elt.name, typename);
                    /* should check typename is the same too */
                    new_dt = &udt->symt;
                }
                PTS_ABORTIF(ptd, stabs_pts_read_aggregate(ptd, udt) == -1);
	    }
	    break;
	case 'x':
	    idx = ptd->idx;
            tmp = *ptd->ptr++;
	    PTS_ABORTIF(ptd, stabs_pts_read_id(ptd) == -1);
	    switch (tmp)
            {
	    case 'e':
                new_dt = &symt_new_enum(ptd->module, ptd->buf + idx)->symt;
                break;
	    case 's':
                new_dt = &symt_new_udt(ptd->module, ptd->buf + idx, 0, UdtStruct)->symt;
	        break;
            case 'u':
                new_dt = &symt_new_udt(ptd->module, ptd->buf + idx, 0, UdtUnion)->symt;
	        break;
	    default:
                return -1;
	    }
	    ptd->idx = idx;
	    break;
	case '-':
            {
                PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &tmp) == -1);
                PTS_ABORTIF(ptd, stabs_get_basic(ptd, tmp, &new_dt) == -1);
                PTS_ABORTIF(ptd, *ptd->ptr++ != ';');
            }
	    break;
        case '#':
            if (*ptd->ptr == '#')
            {
                ptd->ptr++;
                PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &ref_dt) == -1);
                new_dt = &symt_new_function_signature(ptd->module, ref_dt)->symt;
            }
            else
            {
                struct symt*    cls_dt;
                struct symt*    pmt_dt;

                PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &cls_dt) == -1);
                PTS_ABORTIF(ptd, *ptd->ptr++ != ',');
                PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &ref_dt) == -1);
                new_dt = &symt_new_function_signature(ptd->module, ref_dt)->symt;
                while (*ptd->ptr == ',')
                {
                    ptd->ptr++;
                    PTS_ABORTIF(ptd, stabs_pts_read_type_def(ptd, NULL, &pmt_dt) == -1);
                }
            }
            break;
        case 'R':
            {
                long    type, len, unk;
                int     basic;
                
                PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &type) == -1);
                PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */
                PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &len) == -1);
                PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */
                PTS_ABORTIF(ptd, stabs_pts_read_number(ptd, &unk) == -1);
                PTS_ABORTIF(ptd, *ptd->ptr++ != ';');	/* ';' */

                switch (type) /* see stabs_get_basic for the details */
                {
                case 1: basic = 12; break;
                case 2: basic = 13; break;
                case 3: basic = 25; break;
                case 4: basic = 26; break;
                case 5: basic = 35; break;
                case 6: basic = 14; break;
                default: PTS_ABORTIF(ptd, 1);
                }
                PTS_ABORTIF(ptd, stabs_get_basic(ptd, basic, &new_dt) == -1);
            }
            break;
	default:
	    ERR("Unknown type '%c'\n", ptd->ptr[-1]);
	    return -1;
	}
    }

    if (!new_dt)
    {
        /* is it a forward declaration that has been filled ? */
	new_dt = *stabs_find_ref(filenr1, subnr1);
        /* if not, this should be void (which is defined as a ref to itself, but we
         * don't correctly catch it)
         */
        if (!new_dt && typename)
        {
            new_dt = &symt_new_basic(ptd->module, btVoid, typename, 0)->symt;
            PTS_ABORTIF(ptd, strcmp(typename, "void"));
        }
    }            

    *stabs_find_ref(filenr1, subnr1) = *ret_dt = new_dt;

    TRACE("Adding (%ld,%ld) %s\n", filenr1, subnr1, typename);

    return 0;
}

static int stabs_parse_typedef(struct module* module, const char* ptr, 
                               const char* typename)
{
    struct ParseTypedefData	ptd;
    struct symt*                dt;
    int				ret = -1;

    /* check for already existing definition */

    TRACE("%s\n", debugstr_a(ptr));
    ptd.module = module;
    ptd.idx = 0;
#ifdef PTS_DEBUG
    ptd.err_idx = 0;
#endif
    for (ptd.ptr = ptr - 1; ;)
    {
        ptd.ptr = strchr(ptd.ptr + 1, ':');
        if (ptd.ptr == NULL || *++ptd.ptr != ':') break;
    }
    if (ptd.ptr)
    {
	if (*ptd.ptr != '(') ptd.ptr++;
        /* most of type definitions take one char, except Tt */
	if (*ptd.ptr != '(') ptd.ptr++;
	ret = stabs_pts_read_type_def(&ptd, typename, &dt);
    }

    if (ret == -1 || *ptd.ptr) 
    {
#ifdef PTS_DEBUG
        int     i;
	TRACE("Failure on %s\n", debugstr_a(ptr));
        if (ret == -1)
        {
            for (i = 0; i < ptd.err_idx; i++)
            {
                TRACE("[%d]: line %d => %s\n", 
                      i, ptd.errors[i].line, debugstr_a(ptd.errors[i].ptr));
            }
        }
        else
            TRACE("[0]: => %s\n", debugstr_a(ptd.ptr));
            
#else
	ERR("Failure on %s at %s\n", debugstr_a(ptr), debugstr_a(ptd.ptr));
#endif
	return FALSE;
    }

    return TRUE;
}

static struct symt* stabs_parse_type(const char* stab)
{
    const char* c = stab - 1;

    /*
     * Look through the stab definition, and figure out what struct symt
     * this represents.  If we have something we know about, assign the
     * type.
     * According to "The \"stabs\" debug format" (Rev 2.130) the name may be
     * a C++ name and contain double colons e.g. foo::bar::baz:t5=*6.
     */
    do
    {
        if ((c = strchr(c + 1, ':')) == NULL) return NULL;
    } while (*++c == ':');

    /*
     * The next characters say more about the type (i.e. data, function, etc)
     * of symbol.  Skip them.  (C++ for example may have Tt).
     * Actually this is a very weak description; I think Tt is the only
     * multiple combination we should see.
     */
    while (*c && *c != '(' && !isdigit(*c))
        c++;
    /*
     * The next is either an integer or a (integer,integer).
     * The stabs_read_type_enum() takes care that stab_types is large enough.
     */
    return *stabs_read_type_enum(&c);
}

struct pending_loc_var
{
    char                name[256];
    struct symt*        type;
    unsigned            offset;
    unsigned            regno;
};

/******************************************************************
 *		stabs_finalize_function
 *
 * Ends function creation: mainly:
 * - cleans up line number information
 * - tries to set up a debug-start tag (FIXME: heuristic to be enhanced)
 * - for stabs which have abolute address in them, initializes the size of the 
 *   function (assuming that current function ends where next function starts)
 */
static void stabs_finalize_function(struct module* module, struct symt_function* func,
                                    unsigned long end)
{
    IMAGEHLP_LINE       il;
   
    if (!func) return;
    symt_normalize_function(module, func);
    /* To define the debug-start of the function, we use the second line number.
     * Not 100% bullet proof, but better than nothing
     */
    if (symt_fill_func_line_info(module, func, func->address, &il) &&
        symt_get_func_line_next(module, &il))
    {
        symt_add_function_point(module, func, SymTagFuncDebugStart, 
                                il.Address - func->address, NULL);
    }
    if (end) func->size = end - func->address;
}

BOOL stabs_parse(struct module* module, unsigned long load_offset, 
                 const void* pv_stab_ptr, int stablen,
                 const char* strs, int strtablen)
{
    struct symt_function*       curr_func = NULL;
    struct symt_block*          block = NULL;
    struct symt_compiland*      compiland = NULL;
    char                        currpath[PATH_MAX]; /* path to current file */
    char                        srcpath[PATH_MAX]; /* path to directory source file is in */
    int                         i, j;
    int                         nstab;
    const char*                 ptr;
    char*                       stabbuff;
    unsigned int                stabbufflen;
    const struct stab_nlist*    stab_ptr = pv_stab_ptr;
    const char*                 strs_end;
    int                         strtabinc;
    char                        symname[4096];
    unsigned                    incl[32];
    int                         incl_stk = -1;
    int                         source_idx = -1;
    struct pending_loc_var*     pending_vars = NULL;
    unsigned                    num_pending_vars = 0;
    unsigned                    num_allocated_pending_vars = 0;
    BOOL                        ret = TRUE;

    nstab = stablen / sizeof(struct stab_nlist);
    strs_end = strs + strtablen;