X-Git-Url: https://git.draconx.ca/gitweb/cdecl99.git/blobdiff_plain/1a419df06c74bc8389316ffbb2cce9d6a2312f63..b9d67c6ec4c59b204883dfbf346e3b7fca54a84b:/src/parse-decl.c
diff --git a/src/parse-decl.c b/src/parse-decl.c
index dd4bd19..7e181c0 100644
--- a/src/parse-decl.c
+++ b/src/parse-decl.c
@@ -1,39 +1,86 @@
/*
- * Parse and validate C declarations.
- * Copyright © 2011 Nick Bowler
+ * Parse and validate C declarations.
+ * Copyright © 2011-2012, 2020-2021, 2023 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"
+#include "errmsg.h"
+
+/*
+ * We can represent type specifiers as a bitmap, which gives us a finite
+ * list of acceptable bitmap values according to the C standard. However,
+ * the "long" specifier is allowed to occur more than once, but only at most
+ * 2 times. Treat it as a special case, assigning an unused bit to represent
+ * the second long.
+ */
+#define MAP_LLONG_BIT 31
+#define MAP_LONG_BIT (CDECL_TYPE_LONG-CDECL_SPEC_TYPE)
+#define CDECL_TYPE_LLONG (CDECL_SPEC_TYPE+MAP_LLONG_BIT)
+
+#include "typemap.h"
/*
- * Determine if a declarator declares an identifier (other than a function
- * parameter).
+ * Convert the declaration specifiers to a bitmap with each bit
+ * corresponding to one specific type specifier.
*/
-static bool is_abstract(struct cdecl_declarator *d)
+static int valid_typespec(struct cdecl_declspec *s)
{
- while (d->child)
- d = d->child;
+ unsigned long map = 0;
+
+ for (struct cdecl_declspec *c = s; c; c = c->next) {
+ unsigned long bit;
- return d->type != CDECL_DECL_IDENT;
+ if (cdecl_spec_kind(c) != CDECL_SPEC_TYPE)
+ continue;
+
+ bit = c->type - CDECL_SPEC_TYPE;
+ assert(bit < MAP_LLONG_BIT);
+ bit = 1ul << bit;
+
+ /* "long" special case */
+ if ((map & bit) == 1ul << MAP_LONG_BIT)
+ bit = 1ul << MAP_LLONG_BIT;
+
+ if (map & bit) {
+ if (bit == 1ul << MAP_LLONG_BIT)
+ cdecl__errmsg(CDECL__ETOOLONG);
+ else
+ cdecl__errmsg(CDECL__EDUPTYPE);
+ return false;
+ }
+ map |= bit;
+ }
+
+ if (typemap_is_valid(map))
+ return true;
+
+ if (map == 0)
+ cdecl__errmsg(CDECL__ENOTYPE);
+ else
+ cdecl__errmsg(CDECL__EBADTYPE);
+
+ return false;
}
/*
@@ -45,14 +92,11 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
{
struct cdecl_declspec *specs = decl->specifiers;
struct cdecl_declarator *d = decl->declarators;
- bool abstract = is_abstract(d);
+ bool abstract = cdecl_is_abstract(d);
unsigned num_storage = 0;
- unsigned long typemap;
-
- typemap = cdecl__build_typemap(specs);
- if (typemap == -1)
- return -1;
+ if (!valid_typespec(specs))
+ return false;
for (struct cdecl_declspec *c = specs; c; c = c->next) {
switch (cdecl_spec_kind(c)) {
@@ -60,23 +104,23 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
if (c->type == CDECL_TYPE_VOID &&
(d->type == CDECL_DECL_IDENT
|| d->type == CDECL_DECL_ARRAY)) {
- fprintf(stderr, "invalid declaration of type void\n");
+ cdecl__errmsg(CDECL__EBADVOID);
return false;
}
continue;
case CDECL_SPEC_STOR:
if (top && abstract) {
- fprintf(stderr, "type names cannot have storage-class specifiers\n");
+ cdecl__errmsg(CDECL__ETYPESTOR);
return false;
}
if (!top && c->type != CDECL_STOR_REGISTER) {
- fprintf(stderr, "function parameters may only have register storage\n");
+ cdecl__errmsg(CDECL__EFUNCSTOR);
return false;
}
if (++num_storage > 1) {
- fprintf(stderr, "too many storage-class specifiers\n");
+ cdecl__errmsg(CDECL__EMANYSTOR);
return false;
}
break;
@@ -86,20 +130,16 @@ static bool valid_declspecs(struct cdecl *decl, bool top)
* pointer qualifier list, which isn't checked here.
*/
if (c->type == CDECL_QUAL_RESTRICT) {
- fprintf(stderr, "only pointer types can be restrict-qualified.\n");
+ cdecl__errmsg(CDECL__EBADQUAL);
return false;
}
break;
case CDECL_SPEC_FUNC:
- if (abstract) {
- fprintf(stderr, "type names cannot have function specifiers\n");
+ if (abstract || !top || d->type != CDECL_DECL_FUNCTION) {
+ cdecl__errmsg(CDECL__ENOTFUNC);
return false;
}
- if (!top || d->type != CDECL_DECL_FUNCTION) {
- fprintf(stderr, "only function declarations may have function specifiers.\n");
- return false;
- }
break;
default:
assert(0);
@@ -126,12 +166,6 @@ 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.
@@ -175,6 +209,8 @@ 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;
}
@@ -241,7 +277,7 @@ reduce_parentheses(struct cdecl_declarator **p, struct cdecl_declarator *d)
}
if (d->child->type != CDECL_DECL_NULL) {
- fprintf(stderr, "invalid function parameter\n");
+ cdecl__errmsg(CDECL__EBADPARAM);
return -1;
}
@@ -265,7 +301,7 @@ reduce_parentheses(struct cdecl_declarator **p, struct cdecl_declarator *d)
if (decl->type == CDECL_DECL_FUNCTION
&& decl->child->type == CDECL_DECL_NULL
&& !function_is_reducible(decl)) {
- fprintf(stderr, "too many parentheses in function\n");
+ cdecl__errmsg(CDECL__EMANYPAREN);
return -1;
}
@@ -275,12 +311,15 @@ 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)
{
struct cdecl_declspec *spec;
struct cdecl *param;
- bool has_void = false;
if (d->type != CDECL_DECL_FUNCTION)
return 0;
@@ -289,24 +328,108 @@ 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) {
+ 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;
+ }
}
}
- 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:
+ cdecl__errmsg(CDECL__ERETFUNC);
return -1;
- } else if (has_void && d->u.function.variadic) {
- fprintf(stderr, "variadic functions cannot have a void parameter\n");
+ case CDECL_DECL_ARRAY:
+ cdecl__errmsg(CDECL__ERETARRAY);
+ 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:
+ cdecl__errmsg(CDECL__EFUNCARRAY);
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) {
+ cdecl__errmsg(CDECL__ERESTRICTFUNC);
+ 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
@@ -344,19 +467,49 @@ static bool forall_declarators(struct cdecl *decl,
return true;
}
-struct cdecl *cdecl_parse_decl(const char *declstr)
+static struct cdecl *do_parse(const char *str, int english_mode)
{
YY_BUFFER_STATE state;
+ yyscan_t scanner;
struct cdecl *decl;
- int rc;
- state = yy_scan_string(declstr);
- rc = yyparse(&decl);
- yy_delete_buffer(state);
+#if YYDEBUG
+ extern int cdecl__yydebug;
+ cdecl__yydebug = 1;
+#endif
+
+ cdecl__init_i18n();
+ if (cdecl__yylex_init_extra(english_mode, &scanner) != 0)
+ return NULL;
+
+ state = cdecl__yy_scan_string(str, scanner);
+ if (cdecl__yyparse(scanner, &decl) != 0)
+ decl = NULL;
+ cdecl__yy_delete_buffer(state, scanner);
+ cdecl__yylex_destroy(scanner);
+
+ return decl;
+}
- if (rc != 0)
+struct cdecl *cdecl_parse_decl(const char *declstr)
+{
+ struct cdecl_declspec *norm_specs;
+ struct cdecl *decl;
+
+ if (!(decl = do_parse(declstr, false)))
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;
@@ -364,6 +517,51 @@ 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)) {
+ cdecl__errmsg(CDECL__EDECLTYPE);
+ goto err;
+ }
+ }
+
+ return decl;
+err:
+ cdecl__free(decl);
+ return NULL;
+}
+
+struct cdecl *cdecl_parse_english(const char *english)
+{
+ struct cdecl *decl;
+
+ if (!(decl = do_parse(english, true)))
+ 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;
@@ -371,6 +569,11 @@ 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);
+}