preproc.c

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 * Common code for defining an smacro
 */
static bool define_smacro(Context *ctx, char *mname, bool casesense,
			  int nparam, Token *expansion)
{
    SMacro *smac, **smhead;
    struct hash_table *smtbl;

    if (smacro_defined(ctx, mname, nparam, &smac, casesense)) {
	if (!smac) {
	    error(ERR_WARNING|ERR_PASS1,
		  "single-line macro `%s' defined both with and"
		  " without parameters", mname);

	    /* Some instances of the old code considered this a failure,
	       some others didn't.  What is the right thing to do here? */
	    free_tlist(expansion);
	    return false;	/* Failure */
	} else {
	    /*
	     * We're redefining, so we have to take over an
	     * existing SMacro structure. This means freeing
	     * what was already in it.
	     */
	    nasm_free(smac->name);
	    free_tlist(smac->expansion);
	}
    } else {
	smtbl  = ctx ? &ctx->localmac : &smacros;
	smhead = (SMacro **) hash_findi_add(smtbl, mname);
	smac = nasm_malloc(sizeof(SMacro));
	smac->next = *smhead;
	*smhead = smac;
    }
    smac->name = nasm_strdup(mname);
    smac->casesense = casesense;
    smac->nparam = nparam;
    smac->expansion = expansion;
    smac->in_progress = false;
    return true;		/* Success */
}

/*
 * Undefine an smacro
 */
static void undef_smacro(Context *ctx, const char *mname)
{
    SMacro **smhead, *s, **sp;
    struct hash_table *smtbl;

    smtbl = ctx ? &ctx->localmac : &smacros;
    smhead = (SMacro **)hash_findi(smtbl, mname, NULL);

    if (smhead) {
	/*
	 * We now have a macro name... go hunt for it.
	 */
	sp = smhead;
	while ((s = *sp) != NULL) {
	    if (!mstrcmp(s->name, mname, s->casesense)) {
		*sp = s->next;
		nasm_free(s->name);
		free_tlist(s->expansion);
		nasm_free(s);
	    } else {
		sp = &s->next;
	    }
	}
    }
}

/*
 * Parse a mmacro specification.
 */
static bool parse_mmacro_spec(Token *tline, MMacro *def, const char *directive)
{
    bool err;

    tline = tline->next;
    skip_white_(tline);
    tline = expand_id(tline);
    if (!tok_type_(tline, TOK_ID)) {
	error(ERR_NONFATAL, "`%s' expects a macro name", directive);
	return false;
    }

    def->name = nasm_strdup(tline->text);
    def->plus = false;
    def->nolist = false;
    def->in_progress = 0;
    def->rep_nest = NULL;
    def->nparam_min = 0;
    def->nparam_max = 0;

    tline = expand_smacro(tline->next);
    skip_white_(tline);
    if (!tok_type_(tline, TOK_NUMBER)) {
	error(ERR_NONFATAL, "`%s' expects a parameter count", directive);
    } else {
	def->nparam_min = def->nparam_max =
	    readnum(tline->text, &err);
	if (err)
	    error(ERR_NONFATAL,
		  "unable to parse parameter count `%s'", tline->text);
    }
    if (tline && tok_is_(tline->next, "-")) {
	tline = tline->next->next;
	if (tok_is_(tline, "*")) {
	    def->nparam_max = INT_MAX;
	} else if (!tok_type_(tline, TOK_NUMBER)) {
	    error(ERR_NONFATAL,
		  "`%s' expects a parameter count after `-'", directive);
	} else {
	    def->nparam_max = readnum(tline->text, &err);
	    if (err) {
		error(ERR_NONFATAL, "unable to parse parameter count `%s'",
		      tline->text);
	    }
	    if (def->nparam_min > def->nparam_max) {
		error(ERR_NONFATAL, "minimum parameter count exceeds maximum");
	    }
	}
    }
    if (tline && tok_is_(tline->next, "+")) {
	tline = tline->next;
	def->plus = true;
    }
    if (tline && tok_type_(tline->next, TOK_ID) &&
	!nasm_stricmp(tline->next->text, ".nolist")) {
	tline = tline->next;
	def->nolist = true;
    }

    /*
     * Handle default parameters.
     */
    if (tline && tline->next) {
	def->dlist = tline->next;
	tline->next = NULL;
	count_mmac_params(def->dlist, &def->ndefs, &def->defaults);
    } else {
	def->dlist = NULL;
	def->defaults = NULL;
    }
    def->expansion = NULL;

        if(def->defaults &&
           def->ndefs > def->nparam_max - def->nparam_min &&
           !def->plus)
         error(ERR_WARNING|ERR_PASS1|ERR_WARN_MDP,
	       "too many default macro parameters");

    return true;
}


/*
 * Decode a size directive
 */
static int parse_size(const char *str) {
    static const char *size_names[] =
	{ "byte", "dword", "oword", "qword", "tword", "word", "yword" };
    static const int sizes[] =
	{ 0, 1, 4, 16, 8, 10, 2, 32 };

    return sizes[bsii(str, size_names, elements(size_names))+1];
}

/**
 * find and process preprocessor directive in passed line
 * Find out if a line contains a preprocessor directive, and deal
 * with it if so.
 *
 * If a directive _is_ found, it is the responsibility of this routine
 * (and not the caller) to free_tlist() the line.
 *
 * @param tline a pointer to the current tokeninzed line linked list
 * @return DIRECTIVE_FOUND or NO_DIRECTIVE_FOUND
 *
 */
static int do_directive(Token * tline)
{
    enum preproc_token i;
    int j;
    bool err;
    int nparam;
    bool nolist;
    bool casesense;
    int k, m;
    int offset;
    char *p, *pp, *mname;
    Include *inc;
    Context *ctx;
    Cond *cond;
    MMacro *mmac, **mmhead;
    Token *t, *tt, *param_start, *macro_start, *last, **tptr, *origline;
    Line *l;
    struct tokenval tokval;
    expr *evalresult;
    MMacro *tmp_defining;       /* Used when manipulating rep_nest */
    int64_t count;
    size_t len;
    int severity;

    origline = tline;

    skip_white_(tline);
    if (!tline || !tok_type_(tline, TOK_PREPROC_ID) ||
        (tline->text[1] == '%' || tline->text[1] == '$'
         || tline->text[1] == '!'))
        return NO_DIRECTIVE_FOUND;

    i = pp_token_hash(tline->text);

    /*
     * If we're in a non-emitting branch of a condition construct,
     * or walking to the end of an already terminated %rep block,
     * we should ignore all directives except for condition
     * directives.
     */
    if (((istk->conds && !emitting(istk->conds->state)) ||
         (istk->mstk && !istk->mstk->in_progress)) && !is_condition(i)) {
        return NO_DIRECTIVE_FOUND;
    }

    /*
     * If we're defining a macro or reading a %rep block, we should
     * ignore all directives except for %macro/%imacro (which nest),
     * %endm/%endmacro, and (only if we're in a %rep block) %endrep.
     * If we're in a %rep block, another %rep nests, so should be let through.
     */
    if (defining && i != PP_MACRO && i != PP_IMACRO &&
        i != PP_ENDMACRO && i != PP_ENDM &&
        (defining->name || (i != PP_ENDREP && i != PP_REP))) {
        return NO_DIRECTIVE_FOUND;
    }

    if (defining) {
        if (i == PP_MACRO || i == PP_IMACRO) {
            nested_mac_count++;
            return NO_DIRECTIVE_FOUND;
        } else if (nested_mac_count > 0) {
            if (i == PP_ENDMACRO) {
                nested_mac_count--;
                return NO_DIRECTIVE_FOUND;
            }
        }
        if (!defining->name) {
            if (i == PP_REP) {
                nested_rep_count++;
                return NO_DIRECTIVE_FOUND;
            } else if (nested_rep_count > 0) {
                if (i == PP_ENDREP) {
                    nested_rep_count--;
                    return NO_DIRECTIVE_FOUND;
                }
            }
        }
    }

    switch (i) {
    case PP_INVALID:
        error(ERR_NONFATAL, "unknown preprocessor directive `%s'",
              tline->text);
        return NO_DIRECTIVE_FOUND;      /* didn't get it */

    case PP_STACKSIZE:
        /* Directive to tell NASM what the default stack size is. The
         * default is for a 16-bit stack, and this can be overriden with
         * %stacksize large.
         * the following form:
         *
         *      ARG arg1:WORD, arg2:DWORD, arg4:QWORD
         */
        tline = tline->next;
        if (tline && tline->type == TOK_WHITESPACE)
            tline = tline->next;
        if (!tline || tline->type != TOK_ID) {
            error(ERR_NONFATAL, "`%%stacksize' missing size parameter");
            free_tlist(origline);
            return DIRECTIVE_FOUND;
        }
        if (nasm_stricmp(tline->text, "flat") == 0) {
            /* All subsequent ARG directives are for a 32-bit stack */
            StackSize = 4;
            StackPointer = "ebp";
            ArgOffset = 8;
            LocalOffset = 0;
        } else if (nasm_stricmp(tline->text, "flat64") == 0) {
            /* All subsequent ARG directives are for a 64-bit stack */
            StackSize = 8;
            StackPointer = "rbp";
            ArgOffset = 8;
            LocalOffset = 0;
        } else if (nasm_stricmp(tline->text, "large") == 0) {
            /* All subsequent ARG directives are for a 16-bit stack,
             * far function call.
             */
            StackSize = 2;
            StackPointer = "bp";
            ArgOffset = 4;
            LocalOffset = 0;
        } else if (nasm_stricmp(tline->text, "small") == 0) {
            /* All subsequent ARG directives are for a 16-bit stack,
             * far function call. We don't support near functions.
             */
            StackSize = 2;
            StackPointer = "bp";
            ArgOffset = 6;
            LocalOffset = 0;
        } else {
            error(ERR_NONFATAL, "`%%stacksize' invalid size type");
            free_tlist(origline);
            return DIRECTIVE_FOUND;
        }
        free_tlist(origline);
        return DIRECTIVE_FOUND;

    case PP_ARG:
        /* TASM like ARG directive to define arguments to functions, in
         * the following form:
         *
         *      ARG arg1:WORD, arg2:DWORD, arg4:QWORD
         */
        offset = ArgOffset;
        do {
            char *arg, directive[256];
            int size = StackSize;

            /* Find the argument name */
            tline = tline->next;
            if (tline && tline->type == TOK_WHITESPACE)
                tline = tline->next;
            if (!tline || tline->type != TOK_ID) {
                error(ERR_NONFATAL, "`%%arg' missing argument parameter");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }
            arg = tline->text;

            /* Find the argument size type */
            tline = tline->next;
            if (!tline || tline->type != TOK_OTHER
                || tline->text[0] != ':') {
                error(ERR_NONFATAL,
                      "Syntax error processing `%%arg' directive");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }
            tline = tline->next;
            if (!tline || tline->type != TOK_ID) {
                error(ERR_NONFATAL, "`%%arg' missing size type parameter");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }

            /* Allow macro expansion of type parameter */
            tt = tokenize(tline->text);
            tt = expand_smacro(tt);
	    size = parse_size(tt->text);
	    if (!size) {
                error(ERR_NONFATAL,
                      "Invalid size type for `%%arg' missing directive");
                free_tlist(tt);
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }
            free_tlist(tt);

	    /* Round up to even stack slots */
	    size = (size+StackSize-1) & ~(StackSize-1);

            /* Now define the macro for the argument */
            snprintf(directive, sizeof(directive), "%%define %s (%s+%d)",
                     arg, StackPointer, offset);
            do_directive(tokenize(directive));
            offset += size;

            /* Move to the next argument in the list */
            tline = tline->next;
            if (tline && tline->type == TOK_WHITESPACE)
                tline = tline->next;
        } while (tline && tline->type == TOK_OTHER && tline->text[0] == ',');
	ArgOffset = offset;
        free_tlist(origline);
        return DIRECTIVE_FOUND;

    case PP_LOCAL:
        /* TASM like LOCAL directive to define local variables for a
         * function, in the following form:
         *
         *      LOCAL local1:WORD, local2:DWORD, local4:QWORD = LocalSize
         *
         * The '= LocalSize' at the end is ignored by NASM, but is
         * required by TASM to define the local parameter size (and used
         * by the TASM macro package).
         */
        offset = LocalOffset;
        do {
            char *local, directive[256];
            int size = StackSize;

            /* Find the argument name */
            tline = tline->next;
            if (tline && tline->type == TOK_WHITESPACE)
                tline = tline->next;
            if (!tline || tline->type != TOK_ID) {
                error(ERR_NONFATAL,
                      "`%%local' missing argument parameter");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }
            local = tline->text;

            /* Find the argument size type */
            tline = tline->next;
            if (!tline || tline->type != TOK_OTHER
                || tline->text[0] != ':') {
                error(ERR_NONFATAL,
                      "Syntax error processing `%%local' directive");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }
            tline = tline->next;
            if (!tline || tline->type != TOK_ID) {
                error(ERR_NONFATAL,
                      "`%%local' missing size type parameter");
                free_tlist(origline);
                return DIRECTIVE_FOUND;
            }

            /* Allow macro expansion of type parameter */
            tt = toke