X-Git-Url: https://git.draconx.ca/gitweb/cdecl99.git/blobdiff_plain/c92cdbdde6876aa06ad07828c8c315c7967128d5..41d0e2f8f2dc0ec50526ff6e4b8ff12936d1f90e:/src/explain.c
diff --git a/src/explain.c b/src/explain.c
index d7edc74..0d9c957 100644
--- a/src/explain.c
+++ b/src/explain.c
@@ -1,149 +1,164 @@
+/*
+ * Render C declarations as English.
+ * Copyright © 2011, 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 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 .
+ */
+
+#include
#include
#include
#include
-#include "cdecl.h"
-#include "typemap.h"
+#include
+#include
+#include
-/* declare [ident] as [storage] [function specs] [other crap] [qualifiers] [type specs] */
+#include "cdecl.h"
+#include "cdecl-internal.h"
+/*
+ * 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
-voutput(char *buf, size_t n, size_t off, const char *fmt, va_list ap)
+explain_prologue(char *buf, size_t n, struct cdecl_declarator *d, bool top)
{
- if (off >= n)
- return vsnprintf(NULL, 0, fmt, ap);
- return vsnprintf(buf+off, n-off, fmt, ap);
+ size_t ret = 0, rc = 0;
+
+ while (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;
+ }
+
+ assert(0);
}
-static size_t output(char *buf, size_t n, size_t off, const char *fmt, ...)
+static size_t
+explain_pointer(char *buf, size_t n, struct cdecl_pointer *p)
{
- va_list ap;
- size_t ret;
+ size_t ret = 0, rc;
- va_start(ap, fmt);
- ret = voutput(buf, n, off, fmt, ap);
- va_end(ap);
+ rc = cdecl__explain_specs(buf, n, p->qualifiers, CDECL_SPEC_QUAL);
+ ret += cdecl__advance(&buf, &n, rc);
- return ret;
+ return ret + snprintf(buf, n, "pointer to");
}
-/* Renders the type qualifiers and type specifiers in canonical form. */
static size_t
-explain_post_specs(char *buf, size_t n, struct cdecl_declspec *s)
+explain_array(char *buf, size_t n, struct cdecl_array *a)
{
- unsigned long qualmap = 0, typemap;
- const char *tag = NULL;
- size_t ret = 0;
-
- typemap = cdecl__build_typemap(s);
- if (typemap == -1)
- return 0;
-
- for (struct cdecl_declspec *c = s; c; c = c->next) {
- switch (cdecl_spec_kind(c)) {
- case CDECL_SPEC_QUAL:
- qualmap |= 1ul << (c->type & 0xff);
- break;
- case CDECL_SPEC_TYPE:
- /* Valid C types have at most one identifier. */
- if (c->ident)
- tag = c->ident;
- break;
- }
+ size_t ret = 0, rc = 0;
+
+ if (a->vla)
+ rc = snprintf(buf, n, "variable-length array");
+ else
+ rc = snprintf(buf, n, "array");
+ ret += cdecl__advance(&buf, &n, rc);
+
+ if (a->vla) {
+ rc = snprintf(buf, n, "%s", a->vla);
+ ret += cdecl__advance(&buf, &n, rc);
+ } else if (a->length) {
+ rc = snprintf(buf, n, "%" PRIuMAX, a->length);
+ ret += cdecl__advance(&buf, &n, rc);
}
- if (qualmap & (1ul << (CDECL_QUAL_RESTRICT & 0xff)))
- ret += output(buf, n, ret, "restrict ");
- if (qualmap & (1ul << (CDECL_QUAL_VOLATILE & 0xff)))
- ret += output(buf, n, ret, "volatile ");
- if (qualmap & (1ul << (CDECL_QUAL_CONST & 0xff)))
- ret += output(buf, n, ret, "const ");
-
- ret += output(buf, n, ret, "%s", cdecl__explain_typemap(typemap));
- if (tag)
- ret += output(buf, n, ret, " %s", tag);
- return ret;
+ return ret + snprintf(buf, n, "of");
}
-static const char *explain_storage(unsigned spec)
+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)
{
- switch (spec) {
- case CDECL_STOR_TYPEDEF:
- return "typedef";
- case CDECL_STOR_EXTERN:
- return "extern";
- case CDECL_STOR_STATIC:
- return "static";
- case CDECL_STOR_AUTO:
- return "auto";
- case CDECL_STOR_REGISTER:
- return "register";
- default:
- abort();
- }
+ size_t ret = 0, rc;
+
+ rc = explain_prologue(buf, n, decl->declarators, top);
+ ret += cdecl__advance(&buf, &n, rc);
+
+ rc = cdecl__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 + cdecl__explain_post_specs(buf, n, decl->specifiers);
}
-/* Renders the storage-class and function specifiers in canonical form. */
-static size_t explain_pre_specs(char *buf, size_t n, struct cdecl_declspec *s)
+static size_t explain_function(char *buf, size_t n, struct cdecl_function *f)
{
- unsigned long funcmap = 0;
- const char *storage = NULL;
- size_t ret = 0;
-
- for (struct cdecl_declspec *c = s; c; c = c->next) {
- switch (cdecl_spec_kind(c)) {
- case CDECL_SPEC_FUNC:
- funcmap |= 1ul << (c->type & 0xff);
- break;
- case CDECL_SPEC_STOR:
- /* Valid C declarations have at most one
- * storage-class specifier. */
- storage = explain_storage(c->type);
- break;
+ 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);
}
}
- 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;
+ return ret + snprintf(buf, n, "returning");
}
-static size_t advance(char **buf, size_t *n, size_t amount)
+static size_t
+explain_declarators(char *buf, size_t n, struct cdecl_declarator *d)
{
- if (!amount)
+ size_t ret = 0, rc;
+
+ if (d->type == CDECL_DECL_IDENT || d->type == CDECL_DECL_NULL)
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;
- }
- }
+ rc = explain_declarators(buf, n, d->child);
+ ret += cdecl__advance(&buf, &n, rc);
- return amount + 1;
+ 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;
-
- /*
- * XXX: This won't work when we add support for more complicated
- * declarators.
- */
- rc = output(buf, n, 0, "declare %s as", decl->declarators->ident);
- ret += advance(&buf, &n, rc);
-
- rc = explain_pre_specs(buf, n, decl->specifiers);
- ret += advance(&buf, &n, rc);
-
- return ret + explain_post_specs(buf, n, decl->specifiers);
+ return explain_decl(buf, n, decl, true);
}