free(d->child);
free(d);
- return 1;
+ return 0;
}
/*
return -1;
}
- return 1;
+ return 0;
}
return 0;
}
/*
- * Function parameters and return types have a few restrictions that are
- * really easy to check in comparison to the above absurdity.
+ * Returns nonzero iff the given specifier list contains a specifier
+ * of the indicated type.
*/
-static int
-check_parameters(struct cdecl_declarator **p, struct cdecl_declarator *d)
+static int have_specifier(struct cdecl_declspec *s, unsigned type)
{
- struct cdecl_declspec *spec;
- struct cdecl *param;
-
- if (d->type != CDECL_DECL_FUNCTION)
- return 0;
-
- for (param = d->u.function.parameters; param; param = param->next) {
- if (!valid_declspecs(param, false))
- return -1;
-
- /* Check for "void" function parameters as a special case. */
- for (spec = param->specifiers; spec; spec = spec->next) {
- if (param->declarators->type != CDECL_DECL_NULL)
- continue;
- if (spec->type != CDECL_TYPE_VOID)
- continue;
-
- if (spec != param->specifiers || spec->next != NULL) {
- cdecl__errmsg(CDECL__EVOIDPARAM);
- return -1;
- } else if (d->u.function.parameters->next) {
- cdecl__errmsg(CDECL__EVOIDPARAM);
- return -1;
- } else if (d->u.function.variadic) {
- cdecl__errmsg(CDECL__EVOIDPARAM);
- return -1;
- }
- }
- }
-
+ for (; s; s = s->next)
+ if (s->type == type)
+ return 1;
return 0;
}
/*
- * Functions cannot return arrays or functions. Since the parse tree is
- * "inside-out", we need to look for functions as the child declarator.
+ * Check syntax restrictions on a function declarator's child declarator.
+ * That is, "pointer to function", "array of function" and "function
+ * returning function".
+ *
+ * Returns -1 if the declaration is invalid, or 0 otherwise.
*/
-static int
-check_rettypes(struct cdecl_declarator **p, struct cdecl_declarator *d)
+static int check_function_child(struct cdecl_declarator *d)
{
- if (!d->child || d->child->type != CDECL_DECL_FUNCTION)
- return 0;
+ struct cdecl_pointer *ptr;
switch (d->type) {
+ case CDECL_DECL_POINTER:
+ ptr = &d->u.pointer;
+ if (have_specifier(ptr->qualifiers, CDECL_QUAL_RESTRICT)) {
+ /* pointer to function cannot be restrict qualified. */
+ cdecl__errmsg(CDECL__ERESTRICTFUNC);
+ return -1;
+ }
+ return 0;
case CDECL_DECL_FUNCTION:
+ /* function returning function is never allowed. */
cdecl__errmsg(CDECL__ERETFUNC);
return -1;
case CDECL_DECL_ARRAY:
- cdecl__errmsg(CDECL__ERETARRAY);
+ /* array of function is never allowed. */
+ cdecl__errmsg(CDECL__EFUNCARRAY);
return -1;
}
return 0;
}
-static int
-check_arrays(struct cdecl_declarator **p, struct cdecl_declarator *d)
+/*
+ * Check a function parameter declaration for validity, which means it has a
+ * valid combination of declaration specifiers and, if it is a void parameter,
+ * that it is the one special case where this is allowed.
+ *
+ * Returns -1 if the declaration is invalid, or 0 otherwise.
+ */
+static int check_function_param(struct cdecl_function *f, struct cdecl *param)
{
- if (!d->child || d->child->type != CDECL_DECL_ARRAY)
- return 0;
-
- switch (d->type) {
- case CDECL_DECL_FUNCTION:
- cdecl__errmsg(CDECL__EFUNCARRAY);
+ if (!valid_declspecs(param, false))
return -1;
+
+ /* Check for "void" function parameters as a special case. */
+ if (param->declarators->type == CDECL_DECL_NULL
+ && have_specifier(param->specifiers, CDECL_TYPE_VOID))
+ {
+ struct cdecl *fp = f->parameters;
+
+ if (f->variadic || fp->next || fp->specifiers->next) {
+ cdecl__errmsg(CDECL__EVOIDPARAM);
+ return -1;
+ }
}
return 0;
}
-static int
-normalize_specs(struct cdecl_declarator **p, struct cdecl_declarator *d)
+/*
+ * Normalize the specifier lists for function parameters, and then check the
+ * function declarator for validity.
+ *
+ * Returns -1 if the declaration is invalid, or 0 otherwise.
+ */
+static int postproc_function(struct cdecl_declarator *d)
{
- struct cdecl_function *func;
- struct cdecl_pointer *ptr;
+ struct cdecl_function *func = &d->u.function;
+ struct cdecl *param;
+ int rc;
- switch (d->type) {
- case CDECL_DECL_POINTER:
- ptr = &d->u.pointer;
- ptr->qualifiers = cdecl__normalize_specs(ptr->qualifiers);
- break;
- case CDECL_DECL_FUNCTION:
- func = &d->u.function;
- for (struct cdecl *i = func->parameters; i; i = i->next)
- i->specifiers = cdecl__normalize_specs(i->specifiers);
- break;
+ for (param = func->parameters; param; param = param->next) {
+ param->specifiers = cdecl__normalize_specs(param->specifiers);
+
+ if ((rc = check_function_param(func, param)) < 0)
+ return rc;
}
- return 0;
+ return check_function_child(d->child);
}
static int
-check_qualifiers(struct cdecl_declarator **p, struct cdecl_declarator *d)
+postproc_common(struct cdecl_declarator **p, struct cdecl_declarator *d)
{
- struct cdecl_declspec *spec;
struct cdecl_pointer *ptr;
- if (!d->child || d->child->type != CDECL_DECL_POINTER)
+ switch (d->type) {
+ case CDECL_DECL_POINTER:
+ ptr = &d->u.pointer;
+ ptr->qualifiers = cdecl__normalize_specs(ptr->qualifiers);
return 0;
-
- ptr = &d->child->u.pointer;
- for (spec = ptr->qualifiers; spec; spec = spec->next) {
- if (spec->type == CDECL_QUAL_RESTRICT
- && d->type == CDECL_DECL_FUNCTION) {
- cdecl__errmsg(CDECL__ERESTRICTFUNC);
+ case CDECL_DECL_FUNCTION:
+ return postproc_function(d);
+ case CDECL_DECL_ARRAY:
+ if (d->child && d->child->type == CDECL_DECL_FUNCTION) {
+ /* function returning array is never allowed. */
+ cdecl__errmsg(CDECL__ERETARRAY);
return -1;
}
+ return 0;
}
return 0;
* depth-first preorder traversal. The function is given a pointer to the
* declarator as well as to the pointer which was used to reach that
* declarator: this can be used to rewrite entire subtrees.
+ *
+ * The called function may return a negative value to indicate an error
+ * which terminates traversal.
+ *
+ * Returns 0 on success, or a negative value on failure.
*/
-static bool forall_declarators(struct cdecl *decl,
+static int forall_declarators(struct cdecl *decl,
int f(struct cdecl_declarator **, struct cdecl_declarator *))
{
struct cdecl_declarator *d, **p;
- for (p = &decl->declarators, d = *p; d; p = &d->child, d = *p) {
- switch (f(p, d)) {
- case 0:
- break;
- case 1:
- d = *p;
- break;
- case -1:
- return false;
- default:
- assert(0);
- }
+ for (p = &decl->declarators; *p; p = &d->child) {
+ int rc;
+
+ rc = f(p, *p);
+ if (rc < 0)
+ return rc;
+ d = *p;
if (d->type == CDECL_DECL_FUNCTION) {
struct cdecl *i;
for (i = d->u.function.parameters; i; i = i->next) {
- if (!forall_declarators(i, f))
- return false;
+ rc = forall_declarators(i, f);
+ if (rc < 0)
+ return rc;
}
}
}
- return true;
+ return 0;
}
static struct cdecl *do_parse(const char *str, int english_mode)
return decl;
}
-struct cdecl *cdecl_parse_decl(const char *declstr)
+static int do_postprocess(struct cdecl *decl, int english_mode)
{
struct cdecl_declspec *norm_specs;
- struct cdecl *decl;
-
- if (!(decl = do_parse(declstr, false)))
- return NULL;
+ struct cdecl *i;
/*
- * Since the top-level specifiers are shared between each top-level
- * declarator, we need to normalize them once and then propagate the
- * new specifier list.
+ * For a C declaration with more than one full declarator, the
+ * specifier list is common to all of them. Normalize it once,
+ * then propagate that to all the linked cdecl structures.
+ *
+ * In english mode, the cdecl structure list always has exactly
+ * one entry so we don't need to do anything differently.
*/
norm_specs = cdecl__normalize_specs(decl->specifiers);
- for (struct cdecl *i = decl; i; i = i->next) {
+ for (i = decl; i; i = i->next)
i->specifiers = norm_specs;
- }
- /* Now perform checks and simplifications on each declarator. */
- for (struct cdecl *i = decl; i; i = i->next) {
- if (!forall_declarators(i, reduce_parentheses))
- goto err;
- if (!forall_declarators(i, simplify_functions))
- goto err;
- if (!forall_declarators(i, check_parameters))
- goto err;
- if (!forall_declarators(i, check_rettypes))
- goto err;
- if (!forall_declarators(i, check_arrays))
- goto err;
- if (!forall_declarators(i, normalize_specs))
- goto err;
- if (!forall_declarators(i, check_qualifiers))
- goto err;
+ for (i = decl; i; i = i->next) {
+ if (!english_mode) {
+ if (forall_declarators(i, reduce_parentheses) < 0)
+ return 0;
+ if (forall_declarators(i, simplify_functions) < 0)
+ return 0;
+ }
+
+ if (forall_declarators(i, postproc_common) < 0)
+ return 0;
if (!valid_declspecs(i, true))
- goto err;
+ return 0;
if (cdecl_is_abstract(i->declarators)
&& (i != decl || i->next)) {
cdecl__errmsg(CDECL__EDECLTYPE);
- goto err;
+ return 0;
}
}
- return decl;
-err:
- cdecl__free(decl);
- return NULL;
+ return 1;
}
-struct cdecl *cdecl_parse_english(const char *english)
+static struct cdecl *parse_common(const char *str, int english_mode)
{
struct cdecl *decl;
- if (!(decl = do_parse(english, true)))
+ if (!(decl = do_parse(str, english_mode)))
return NULL;
- for (struct cdecl *i = decl; i; i = i->next) {
- i->specifiers = cdecl__normalize_specs(i->specifiers);
-
- if (!forall_declarators(i, check_parameters))
- goto err;
- if (!forall_declarators(i, check_rettypes))
- goto err;
- if (!forall_declarators(i, check_arrays))
- goto err;
- if (!forall_declarators(i, normalize_specs))
- goto err;
- if (!forall_declarators(i, check_qualifiers))
- goto err;
-
- if (!valid_declspecs(i, true))
- goto err;
+ if (!do_postprocess(decl, english_mode)) {
+ cdecl__free(decl);
+ return NULL;
}
return decl;
-err:
- cdecl__free(decl);
- return NULL;
+}
+
+struct cdecl *cdecl_parse_decl(const char *declstr)
+{
+ return parse_common(declstr, false);
+}
+
+struct cdecl *cdecl_parse_english(const char *english)
+{
+ return parse_common(english, true);
}
void cdecl_free(struct cdecl *decl)