]> git.draconx.ca Git - cdecl99.git/blobdiff - src/parse-decl.c
Rework library error reporting.
[cdecl99.git] / src / parse-decl.c
index 3ffb1029ae181b596da102f367130f5f84bd83c4..f00442d31712c2dffef54ecf10bb8aa6c0b8d66b 100644 (file)
@@ -1,39 +1,85 @@
 /*
- *  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 <http://www.gnu.org/licenses/>.
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
+
+#include <config.h>
 #include <stdio.h>
 #include <assert.h>
 #include <stdbool.h>
 
 #include "cdecl.h"
-#include "typemap.h"
+#include "cdecl-internal.h"
 #include "parse.h"
 #include "scan.h"
 
 /*
- * Determine if a declarator declares an identifier (other than a function
- * parameter).
+ * 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"
+
+/*
+ * 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;
+
+               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__err(CDECL_EBADTYPE, _("too many long specifiers"));
+                       else
+                               cdecl__err(CDECL_EBADTYPE, _("duplicate type specifier"));
+                       return false;
+               }
+               map |= bit;
+       }
+
+       if (typemap_is_valid(map))
+               return true;
 
-       return d->type != CDECL_DECL_IDENT;
+       if (map == 0)
+               cdecl__err(CDECL_EBADTYPE, _("no type specified"));
+       else
+               cdecl__err(CDECL_EBADTYPE, _("invalid type specified"));
+
+       return false;
 }
 
 /*
@@ -45,12 +91,10 @@ 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)
+       if (!valid_typespec(specs))
                return false;
 
        for (struct cdecl_declspec *c = specs; c; c = c->next) {
@@ -59,23 +103,23 @@ 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__err(CDECL_EBADTYPE, _("invalid declaration of type void"));
                                return false;
                        }
                        continue;
                case CDECL_SPEC_STOR:
                        if (top && abstract) {
-                               fprintf(stderr, "type names cannot have storage-class specifiers\n");
+                               cdecl__err(CDECL_EBADSTOR, _("type names cannot have storage-class specifiers"));
                                return false;
                        }
 
                        if (!top && c->type != CDECL_STOR_REGISTER) {
-                               fprintf(stderr, "function parameters may only have register storage\n");
+                               cdecl__err(CDECL_EBADSTOR, _("function parameters may only have register storage"));
                                return false;
                        }
 
                        if (++num_storage > 1) {
-                               fprintf(stderr, "too many storage-class specifiers\n");
+                               cdecl__err(CDECL_EBADSTOR, _("too many storage-class specifiers"));
                                return false;
                        }
                        break;
@@ -85,18 +129,18 @@ 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__err(CDECL_EBADQUAL, _("only pointer types can be restrict-qualified"));
                                return false;
                        }
                        break;
                case CDECL_SPEC_FUNC:
                        if (abstract) {
-                               fprintf(stderr, "type names cannot have function specifiers\n");
+                               cdecl__err(CDECL_ENOTFUNC, _("type names cannot have function specifiers"));
                                return false;
                        }
 
                        if (!top || d->type != CDECL_DECL_FUNCTION) {
-                               fprintf(stderr, "only function declarations may have function specifiers.\n");
+                               cdecl__err(CDECL_ENOTFUNC, _("only function declarations can have function specifiers"));
                                return false;
                        }
                        break;
@@ -125,12 +169,6 @@ 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.
@@ -174,6 +212,8 @@ 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;
 }
@@ -240,7 +280,7 @@ reduce_parentheses(struct cdecl_declarator **p, struct cdecl_declarator *d)
                }
 
                if (d->child->type != CDECL_DECL_NULL) {
-                       fprintf(stderr, "invalid function parameter\n");
+                       cdecl__err(CDECL_EBADPARAMS, _("invalid function parameter"));
                        return -1;
                }
 
@@ -264,7 +304,7 @@ 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__err(CDECL_EBADPARAMS, _("too many parentheses in function"));
                        return -1;
                }
 
@@ -283,7 +323,6 @@ 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;
@@ -292,21 +331,26 @@ 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__err(CDECL_EVOIDPARAM, _("void parameter cannot have extra specifiers"));
+                               return -1;
+                       } else if (d->u.function.parameters->next) {
+                               cdecl__err(CDECL_EVOIDPARAM, _("void parameter must stand alone"));
+                               return -1;
+                       } else if (d->u.function.variadic) {
+                               cdecl__err(CDECL_EVOIDPARAM, _("variadic function cannot have void parameter"));
+                               return -1;
+                       }
                }
        }
 
-       if (has_void && d->u.function.parameters->next) {
-               fprintf(stderr, "a void parameter must stand alone\n");
-               return -1;
-       } else if (has_void && d->u.function.variadic) {
-               fprintf(stderr, "variadic functions cannot have a void parameter\n");
-               return -1;
-       }
-
        return 0;
 }
 
@@ -322,10 +366,10 @@ check_rettypes(struct cdecl_declarator **p, struct cdecl_declarator *d)
 
        switch (d->type) {
        case CDECL_DECL_FUNCTION:
-               fprintf(stderr, "functions cannot return functions\n");
+               cdecl__err(CDECL_EBADRETURN, _("functions cannot return functions"));
                return -1;
        case CDECL_DECL_ARRAY:
-               fprintf(stderr, "functions cannot return arrays\n");
+               cdecl__err(CDECL_EBADRETURN, _("functions cannot return arrays"));
                return -1;
        }
 
@@ -340,13 +384,55 @@ check_arrays(struct cdecl_declarator **p, struct cdecl_declarator *d)
 
        switch (d->type) {
        case CDECL_DECL_FUNCTION:
-               fprintf(stderr, "array members cannot be functions\n");
+               cdecl__err(CDECL_EBADARRAY, _("array members cannot be functions"));
                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__err(CDECL_EBADPOINTER, _("function pointers cannot be restrict-qualified"));
+                       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
@@ -386,11 +472,14 @@ 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;
 
+       cdecl__init_i18n();
+
        rc = cdecl__yylex_init(&scanner);
        if (rc != 0)
                return NULL;
@@ -403,6 +492,17 @@ struct cdecl *cdecl_parse_decl(const char *declstr)
        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;
@@ -414,19 +514,24 @@ struct cdecl *cdecl_parse_decl(const char *declstr)
                        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 (is_abstract(i->declarators) && (i != decl || i->next)) {
-                       fprintf(stderr, "mixing type names and declarations is not allowed\n");
+               if (cdecl_is_abstract(i->declarators)
+                   && (i != decl || i->next)) {
+                       cdecl__err(CDECL_EBADDECL, _("mixing type names and declarations is not allowed"));
                        goto err;
                }
        }
 
        return decl;
 err:
-       cdecl_free(decl);
+       cdecl__free(decl);
        return NULL;
 }
 
@@ -437,6 +542,8 @@ struct cdecl *cdecl_parse_english(const char *english)
        struct cdecl *decl;
        int rc;
 
+       cdecl__init_i18n();
+
        rc = cdecl__yylex_init_extra(true, &scanner);
        if (rc != 0)
                return NULL;
@@ -450,12 +557,18 @@ struct cdecl *cdecl_parse_english(const char *english)
                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;
@@ -463,6 +576,11 @@ struct cdecl *cdecl_parse_english(const char *english)
 
        return decl;
 err:
-       cdecl_free(decl);
+       cdecl__free(decl);
        return NULL;
 }
+
+void cdecl_free(struct cdecl *decl)
+{
+       cdecl__free(decl);
+}