X-Git-Url: https://git.draconx.ca/gitweb/cdecl99.git/blobdiff_plain/34d65b55a47f66bb907d30ae2b65c4fb64f38cc5..0c61f9637a469ac7a28b5a329551b03e6ad14d62:/src/parse-decl.c
diff --git a/src/parse-decl.c b/src/parse-decl.c
index c210f7c..2757703 100644
--- a/src/parse-decl.c
+++ b/src/parse-decl.c
@@ -1,26 +1,28 @@
/*
- * Parse and validate C declarations.
- * Copyright © 2011 Nick Bowler
+ * Parse and validate C declarations.
+ * Copyright © 2011-2012, 2020-2021 Nick Bowler
*
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
*
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
*
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see .
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
*/
+
+#include
#include
#include
#include
#include "cdecl.h"
-#include "typemap.h"
+#include "cdecl-internal.h"
#include "parse.h"
#include "scan.h"
@@ -33,12 +35,13 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
{
struct cdecl_declspec *specs = decl->specifiers;
struct cdecl_declarator *d = decl->declarators;
+ bool abstract = cdecl_is_abstract(d);
unsigned num_storage = 0;
unsigned long typemap;
typemap = cdecl__build_typemap(specs);
if (typemap == -1)
- return -1;
+ return false;
for (struct cdecl_declspec *c = specs; c; c = c->next) {
switch (cdecl_spec_kind(c)) {
@@ -51,6 +54,11 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
}
continue;
case CDECL_SPEC_STOR:
+ if (top && abstract) {
+ fprintf(stderr, "type names cannot have storage-class specifiers\n");
+ return false;
+ }
+
if (!top && c->type != CDECL_STOR_REGISTER) {
fprintf(stderr, "function parameters may only have register storage\n");
return false;
@@ -72,6 +80,11 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
}
break;
case CDECL_SPEC_FUNC:
+ if (abstract) {
+ fprintf(stderr, "type names cannot have function specifiers\n");
+ return false;
+ }
+
if (!top || d->type != CDECL_DECL_FUNCTION) {
fprintf(stderr, "only function declarations may have function specifiers.\n");
return false;
@@ -102,12 +115,6 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
* if a declarator could be interpreted as something other than a function,
* do that.
*
- * - The function declarator has a null child declarator.
- * - The function declarator has exactly one parameter, and is not variadic.
- * - The function parameter has a type specifier, and it is a typedef name.
- * - The function parameter has no other declaration specifiers.
- * - The function parameter does not declare an identifier.
- *
* Since cdecl99 supports things like [*] in any context (in C, such constructs
* are only valid in function parameter lists), we don't treat them specially
* here.
@@ -151,6 +158,8 @@ static bool function_is_reducible(struct cdecl_declarator *d)
return false; /* e.g. int (int) */
if (d->u.function.parameters->specifiers->next)
return false; /* e.g. int (size_t const) */
+ if (d->u.function.parameters->declarators->type == CDECL_DECL_POINTER)
+ return false; /* e.g. int (x *) */
return true;
}
@@ -251,6 +260,10 @@ reduce_parentheses(struct cdecl_declarator **p, struct cdecl_declarator *d)
return 0;
}
+/*
+ * Function parameters and return types have a few restrictions that are
+ * really easy to check in comparison to the above absurdity.
+ */
static int
check_parameters(struct cdecl_declarator **p, struct cdecl_declarator *d)
{
@@ -265,24 +278,108 @@ check_parameters(struct cdecl_declarator **p, struct cdecl_declarator *d)
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 (spec->type == CDECL_TYPE_VOID
- && param->declarators->type == CDECL_DECL_NULL)
- has_void = true;
+ if (param->declarators->type != CDECL_DECL_NULL)
+ continue;
+ if (spec->type != CDECL_TYPE_VOID)
+ continue;
+
+ if (spec != param->specifiers || spec->next != NULL) {
+ fprintf(stderr, "void parameter must not have extra specifiers\n");
+ return -1;
+ } else if (d->u.function.parameters->next) {
+ fprintf(stderr, "a void parameter must stand alone\n");
+ return -1;
+ } else if (d->u.function.variadic) {
+ fprintf(stderr, "variadic functions cannot have a void parameter\n");
+ return -1;
+ }
}
}
- if (has_void && d->u.function.parameters->next) {
- fprintf(stderr, "a void parameter must stand alone\n");
+ 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.
+ */
+static int
+check_rettypes(struct cdecl_declarator **p, struct cdecl_declarator *d)
+{
+ if (!d->child || d->child->type != CDECL_DECL_FUNCTION)
+ return 0;
+
+ switch (d->type) {
+ case CDECL_DECL_FUNCTION:
+ fprintf(stderr, "functions cannot return functions\n");
return -1;
- } else if (has_void && d->u.function.variadic) {
- fprintf(stderr, "variadic functions cannot have a void parameter\n");
+ case CDECL_DECL_ARRAY:
+ fprintf(stderr, "functions cannot return arrays\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int
+check_arrays(struct cdecl_declarator **p, struct cdecl_declarator *d)
+{
+ if (!d->child || d->child->type != CDECL_DECL_ARRAY)
+ return 0;
+
+ switch (d->type) {
+ case CDECL_DECL_FUNCTION:
+ fprintf(stderr, "array members cannot be functions\n");
return -1;
}
return 0;
}
+static int
+normalize_specs(struct cdecl_declarator **p, struct cdecl_declarator *d)
+{
+ struct cdecl_function *func;
+ struct cdecl_pointer *ptr;
+
+ 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;
+ }
+
+ return 0;
+}
+
+static int
+check_qualifiers(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)
+ 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) {
+ fprintf(stderr, "function pointers cannot be restrict-qualified\n");
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
/*
* Traverse the parse tree, calling a function on every declarator in a
* depth-first preorder traversal. The function is given a pointer to the
@@ -322,17 +419,37 @@ static bool forall_declarators(struct cdecl *decl,
struct cdecl *cdecl_parse_decl(const char *declstr)
{
+ struct cdecl_declspec *norm_specs;
YY_BUFFER_STATE state;
+ yyscan_t scanner;
struct cdecl *decl;
int rc;
- state = yy_scan_string(declstr);
- rc = yyparse(&decl);
- yy_delete_buffer(state);
+ cdecl__init_i18n();
+ rc = cdecl__yylex_init(&scanner);
if (rc != 0)
return NULL;
+ state = cdecl__yy_scan_string(declstr, scanner);
+ rc = cdecl__yyparse(scanner, &decl);
+ cdecl__yy_delete_buffer(state, scanner);
+ cdecl__yylex_destroy(scanner);
+
+ if (rc != 0)
+ return NULL;
+
+ /*
+ * 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.
+ */
+ norm_specs = cdecl__normalize_specs(decl->specifiers);
+ for (struct cdecl *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;
@@ -340,6 +457,65 @@ struct cdecl *cdecl_parse_decl(const char *declstr)
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;
+
+ if (!valid_declspecs(i, true))
+ goto err;
+
+ if (cdecl_is_abstract(i->declarators)
+ && (i != decl || i->next)) {
+ fprintf(stderr, "mixing type names and declarations is not allowed\n");
+ goto err;
+ }
+ }
+
+ return decl;
+err:
+ cdecl__free(decl);
+ return NULL;
+}
+
+struct cdecl *cdecl_parse_english(const char *english)
+{
+ YY_BUFFER_STATE state;
+ yyscan_t scanner;
+ struct cdecl *decl;
+ int rc;
+
+ cdecl__init_i18n();
+
+ rc = cdecl__yylex_init_extra(true, &scanner);
+ if (rc != 0)
+ return NULL;
+
+ state = cdecl__yy_scan_string(english, scanner);
+ rc = cdecl__yyparse(scanner, &decl);
+ cdecl__yy_delete_buffer(state, scanner);
+ cdecl__yylex_destroy(scanner);
+
+ if (rc != 0)
+ 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;
@@ -347,6 +523,11 @@ struct cdecl *cdecl_parse_decl(const char *declstr)
return decl;
err:
- cdecl_free(decl);
+ cdecl__free(decl);
return NULL;
}
+
+void cdecl_free(struct cdecl *decl)
+{
+ cdecl__free(decl);
+}