src/declare.c

   1 /*
   2  *  Render C declarations.
   3  *  Copyright © 2011 Nick Bowler
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 #include <config.h>
  19 #include <stdio.h>
  20 #include <assert.h>
  21
  22 #include "cdecl.h"
  23 #include "output.h"
  24
  25 static size_t declare_specs(char *buf, size_t n, struct cdecl_declspec *s)
  26 {
  27         size_t ret = 0, rc;
  28
  29         if (!s)
  30                 return 0;
  31
  32         rc = cdecl__explain_pre_specs(buf, n, s);
  33         ret += cdecl__advance(&buf, &n, rc);
  34
  35         rc = cdecl__explain_post_specs(buf, n, s);
  36         return ret + rc;
  37 }
  38
  39 static size_t
  40 declare_declarator(char *buf, size_t n, struct cdecl_declarator *d);
  41
  42 static size_t declare_decl(char *buf, size_t n, struct cdecl *decl)
  43 {
  44         size_t ret = 0, rc;
  45
  46         rc = declare_specs(buf, n, decl->specifiers);
  47         if (decl->declarators->type != CDECL_DECL_NULL)
  48                 ret += cdecl__advance(&buf, &n, rc);
  49         else
  50                 ret += cdecl__advance_(&buf, &n, rc);
  51
  52         return ret + declare_declarator(buf, n, decl->declarators);
  53 }
  54
  55 static size_t
  56 declare_postfix_child(char *buf, size_t n, struct cdecl_declarator *d)
  57 {
  58         size_t ret = 0, rc;
  59
  60         if (d->type == CDECL_DECL_POINTER) {
  61                 rc = snprintf(buf, n, "(");
  62                 ret += cdecl__advance_(&buf, &n, rc);
  63         }
  64
  65         rc = declare_declarator(buf, n, d);
  66         ret += cdecl__advance_(&buf, &n, rc);
  67
  68         if (d->type == CDECL_DECL_POINTER) {
  69                 rc = snprintf(buf, n, ")");
  70                 ret += cdecl__advance_(&buf, &n, rc);
  71         }
  72
  73         return ret;
  74 }
  75
  76 static size_t declare_pointer(char *buf, size_t n, struct cdecl_pointer *p)
  77 {
  78         size_t ret = 0, rc;
  79
  80         rc = snprintf(buf, n, "*");
  81         if (p->qualifiers)
  82                 ret += cdecl__advance(&buf, &n, rc);
  83         else
  84                 ret += cdecl__advance_(&buf, &n, rc);
  85
  86         rc = cdecl__explain_specs(buf, n, p->qualifiers, CDECL_SPEC_QUAL);
  87         return ret + cdecl__advance(&buf, &n, rc);
  88 }
  89
  90 static size_t declare_array(char *buf, size_t n, struct cdecl_array *a)
  91 {
  92         size_t ret = 0, rc;
  93
  94         rc = snprintf(buf, n, "[");
  95         ret += cdecl__advance_(&buf, &n, rc);
  96
  97         if (a->vla)
  98                 rc = snprintf(buf, n, "%s", a->vla[0] ? a->vla : "*");
  99         else
 100                 rc = snprintf(buf, n, "%.0ju", a->length);
 101         ret += cdecl__advance_(&buf, &n, rc);
 102
 103         return ret + snprintf(buf, n, "]");
 104 }
 105
 106 static size_t declare_function(char *buf, size_t n, struct cdecl_function *f)
 107 {
 108         size_t ret = 0, rc;
 109
 110         rc = snprintf(buf, n, "(");
 111         ret += cdecl__advance_(&buf, &n, rc);
 112
 113         for (struct cdecl *p = f->parameters; p; p = p->next) {
 114                 rc = declare_decl(buf, n, p);
 115                 ret += cdecl__advance_(&buf, &n, rc);
 116
 117                 rc = 0;
 118                 if (p->next)
 119                         rc = snprintf(buf, n, ", ");
 120                 else if (f->variadic)
 121                         rc = snprintf(buf, n, ", ...");
 122                 ret += cdecl__advance_(&buf, &n, rc);
 123         }
 124
 125         return ret + snprintf(buf, n, ")");
 126 }
 127
 128 static size_t
 129 declare_declarator(char *buf, size_t n, struct cdecl_declarator *d)
 130 {
 131         size_t ret = 0, rc;
 132
 133         for (; d; d = d->child) {
 134                 switch (d->type) {
 135                 case CDECL_DECL_NULL:
 136                         break;
 137                 case CDECL_DECL_IDENT:
 138                         rc = snprintf(buf, n, "%s", d->u.ident);
 139                         ret += cdecl__advance_(&buf, &n, rc);
 140                         break;
 141                 case CDECL_DECL_POINTER:
 142                         rc = declare_pointer(buf, n, &d->u.pointer);
 143                         ret += cdecl__advance_(&buf, &n, rc);
 144                         break;
 145                 /*
 146                  * Arrays and functions are special: since they are postfix,
 147                  * we need to render the children before rendering their
 148                  * "bodies".
 149                  */
 150                 case CDECL_DECL_ARRAY:
 151                         rc = declare_postfix_child(buf, n, d->child);
 152                         ret += cdecl__advance_(&buf, &n, rc);
 153                         return ret + declare_array(buf, n, &d->u.array);
 154                 case CDECL_DECL_FUNCTION:
 155                         rc = declare_postfix_child(buf, n, d->child);
 156                         ret += cdecl__advance_(&buf, &n, rc);
 157                         return ret + declare_function(buf, n, &d->u.function);
 158                 default:
 159                         assert(0);
 160                 }
 161         }
 162
 163         return ret;
 164 }
 165
 166 size_t cdecl_declare(char *buf, size_t n, struct cdecl *decl)
 167 {
 168         return declare_decl(buf, n, decl);
 169 }