+/*
+ * Render C declarations as English.
+ * Copyright © 2011 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 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/>.
+ */
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
+#include <stdbool.h>
#include <assert.h>
#include "cdecl.h"
#include "typemap.h"
-
-/* declare [ident] as [storage] [function specs] [other crap] [qualifiers] [type specs] */
-
-static size_t
-voutput(char *buf, size_t n, size_t off, const char *fmt, va_list ap)
-{
- if (off >= n)
- return vsnprintf(NULL, 0, fmt, ap);
- return vsnprintf(buf+off, n-off, fmt, ap);
-}
-
-static size_t output(char *buf, size_t n, size_t off, const char *fmt, ...)
-{
- va_list ap;
- size_t ret;
-
- va_start(ap, fmt);
- ret = voutput(buf, n, off, fmt, ap);
- va_end(ap);
-
- return ret;
-}
-
-static size_t advance(char **buf, size_t *n, size_t amount)
-{
- if (!amount)
- return 0;
-
- if (amount >= *n) {
- *n = 0;
- *buf = 0;
- } else {
- (*buf)[amount] = ' ';
- if (amount + 1 >= *n) {
- *buf = 0;
- *n = 0;
- } else {
- *buf += amount + 1;
- *n -= amount + 1;
- }
- }
-
- return amount + 1;
-}
+#include "output.h"
static size_t
explain_qualifiers(char *buf, size_t n, struct cdecl_declspec *s)
}
if (qualmap & (1ul << (CDECL_QUAL_RESTRICT & 0xff))) {
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
rc = snprintf(buf, n, "restrict");
}
if (qualmap & (1ul << (CDECL_QUAL_VOLATILE & 0xff))) {
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
rc = snprintf(buf, n, "volatile");
}
if (qualmap & (1ul << (CDECL_QUAL_CONST & 0xff))) {
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
rc = snprintf(buf, n, "const");
}
}
rc = explain_qualifiers(buf, n, s);
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
rc = snprintf(buf, n, "%s", cdecl__explain_typemap(typemap));
if (tag) {
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
rc = snprintf(buf, n, "%s", tag);
}
return ret + rc;
}
-static const char *explain_storage(unsigned spec)
+static size_t explain_storage(char *buf, size_t n, unsigned spec)
{
switch (spec) {
case CDECL_STOR_TYPEDEF:
- return "typedef";
+ return snprintf(buf, n, "typedef");
case CDECL_STOR_EXTERN:
- return "extern";
+ return snprintf(buf, n, "extern");
case CDECL_STOR_STATIC:
- return "static";
+ return snprintf(buf, n, "static");
case CDECL_STOR_AUTO:
- return "auto";
+ return snprintf(buf, n, "auto");
case CDECL_STOR_REGISTER:
- return "register";
+ return snprintf(buf, n, "register");
default:
assert(0);
}
static size_t explain_pre_specs(char *buf, size_t n, struct cdecl_declspec *s)
{
unsigned long funcmap = 0;
- const char *storage = NULL;
- size_t ret = 0;
+ size_t ret = 0, rc = 0;
for (struct cdecl_declspec *c = s; c; c = c->next) {
switch (cdecl_spec_kind(c)) {
case CDECL_SPEC_STOR:
/* Valid C declarations have at most one
* storage-class specifier. */
- storage = explain_storage(c->type);
+ rc = explain_storage(buf, n, c->type);
break;
}
}
- if (storage)
- ret += output(buf, n, ret, "%s", storage);
- if (funcmap & (1ul << (CDECL_FUNC_INLINE & 0xff)))
- ret += output(buf, n, ret, "%.*s%s", !!ret, "", "inline");
- return ret;
-}
-
-static struct cdecl_declarator *next_declarator(struct cdecl_declarator *d)
-{
- switch (d->type) {
- case CDECL_DECL_IDENT:
- return NULL;
- case CDECL_DECL_POINTER:
- return d->u.pointer.declarator;
- case CDECL_DECL_ARRAY:
- return d->u.array.declarator;
- default:
- assert(0);
+ if (funcmap & (1ul << (CDECL_FUNC_INLINE & 0xff))) {
+ ret += cdecl__advance(&buf, &n, rc);
+ rc = snprintf(buf, n, "inline");
}
+
+ return ret + rc;
}
-/* Renders the name of the thing being declared. */
+/*
+ * Renders the start of the thing being declared. If top is true, print
+ * the "declare" or "type" keywords at the front, as appropriate.
+ */
static size_t
-explain_prologue(char *buf, size_t n, struct cdecl_declarator *d)
+explain_prologue(char *buf, size_t n, struct cdecl_declarator *d, bool top)
{
+ size_t ret = 0, rc = 0;
+
while (d) {
- if (d->type == CDECL_DECL_IDENT)
- return snprintf(buf, n, "declare %s as", d->u.ident);
- d = next_declarator(d);
+ switch (d->type) {
+ case CDECL_DECL_NULL:
+ if (top)
+ return snprintf(buf, n, "type");
+ return 0;
+ case CDECL_DECL_IDENT:
+ if (top)
+ rc = snprintf(buf, n, "declare");
+ ret += cdecl__advance(&buf, &n, rc);
+ return ret + snprintf(buf, n, "%s as", d->u.ident);
+ }
+
+ d = d->child;
}
}
size_t ret = 0, rc;
rc = explain_qualifiers(buf, n, p->qualifiers);
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
return ret + snprintf(buf, n, "pointer to");
}
rc = snprintf(buf, n, "variable-length array");
else
rc = snprintf(buf, n, "array");
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
if (a->vla) {
rc = snprintf(buf, n, "%s", a->vla);
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
} else if (a->length) {
rc = snprintf(buf, n, "%ju", a->length);
- ret += advance(&buf, &n, rc);
+ ret += cdecl__advance(&buf, &n, rc);
}
return ret + snprintf(buf, n, "of");
}
+static size_t
+explain_declarators(char *buf, size_t n, struct cdecl_declarator *decl);
+
+static size_t explain_decl(char *buf, size_t n, struct cdecl *decl, bool top)
+{
+ size_t ret = 0, rc;
+
+ rc = explain_prologue(buf, n, decl->declarators, top);
+ ret += cdecl__advance(&buf, &n, rc);
+
+ rc = explain_pre_specs(buf, n, decl->specifiers);
+ ret += cdecl__advance(&buf, &n, rc);
+
+ rc = explain_declarators(buf, n, decl->declarators);
+ ret += cdecl__advance(&buf, &n, rc);
+
+ return ret + explain_post_specs(buf, n, decl->specifiers);
+}
+
+static size_t explain_function(char *buf, size_t n, struct cdecl_function *f)
+{
+ size_t ret = 0, rc = 0;
+
+ rc = snprintf(buf, n, "function");
+ ret += cdecl__advance(&buf, &n, rc);
+
+ if (f->parameters) {
+ rc = snprintf(buf, n, "(");
+ ret += cdecl__advance_(&buf, &n, rc);
+
+ for (struct cdecl *p = f->parameters; p; p = p->next) {
+ rc = explain_decl(buf, n, p, false);
+ ret += cdecl__advance_(&buf, &n, rc);
+
+ if (p->next)
+ rc = snprintf(buf, n, ",");
+ else if (f->variadic)
+ rc = snprintf(buf, n, ", ...)");
+ else
+ rc = snprintf(buf, n, ")");
+ ret += cdecl__advance(&buf, &n, rc);
+ }
+ }
+
+ return ret + snprintf(buf, n, "returning");
+}
+
static size_t
explain_declarators(char *buf, size_t n, struct cdecl_declarator *d)
{
size_t ret = 0, rc;
- if (d->type == CDECL_DECL_IDENT)
+ if (d->type == CDECL_DECL_IDENT || d->type == CDECL_DECL_NULL)
return 0;
- rc = explain_declarators(buf, n, next_declarator(d));
- ret += advance(&buf, &n, rc);
+ rc = explain_declarators(buf, n, d->child);
+ ret += cdecl__advance(&buf, &n, rc);
switch (d->type) {
case CDECL_DECL_POINTER:
return ret + explain_pointer(buf, n, &d->u.pointer);
case CDECL_DECL_ARRAY:
return ret + explain_array(buf, n, &d->u.array);
+ case CDECL_DECL_FUNCTION:
+ return ret + explain_function(buf, n, &d->u.function);
default:
assert(0);
}
size_t cdecl_explain(char *buf, size_t n, struct cdecl *decl)
{
- size_t ret = 0, rc;
-
- rc = explain_prologue(buf, n, decl->declarators);
- ret += advance(&buf, &n, rc);
-
- rc = explain_pre_specs(buf, n, decl->specifiers);
- ret += advance(&buf, &n, rc);
-
- rc = explain_declarators(buf, n, decl->declarators);
- ret += advance(&buf, &n, rc);
-
- return ret + explain_post_specs(buf, n, decl->specifiers);
+ return explain_decl(buf, n, decl, true);
}