src/glsl/pp/sl_pp_if.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include "sl_pp_expression.h"
  31 #include "sl_pp_process.h"
  32
  33
  34 static int
  35 _macro_is_defined(struct sl_pp_context *context,
  36                   int macro_name)
  37 {
  38    unsigned int i;
  39    struct sl_pp_macro *macro;
  40
  41    for (i = 0; i < context->num_extensions; i++) {
  42       if (macro_name == context->extensions[i].name) {
  43          return context->extensions[i].enabled;
  44       }
  45    }
  46
  47    for (macro = context->macro; macro; macro = macro->next) {
  48       if (macro_name == macro->name) {
  49          return 1;
  50       }
  51    }
  52
  53    return 0;
  54 }
  55
  56 static int
  57 _parse_defined(struct sl_pp_context *context,
  58                struct sl_pp_token_buffer *buffer,
  59                struct sl_pp_process_state *state)
  60 {
  61    struct sl_pp_token_info input;
  62    int parens = 0;
  63    int defined;
  64    struct sl_pp_token_info result;
  65
  66    if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  67       return -1;
  68    }
  69
  70    if (input.token == SL_PP_LPAREN) {
  71       if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  72          return -1;
  73       }
  74       parens = 1;
  75    }
  76
  77    if (input.token != SL_PP_IDENTIFIER) {
  78       strcpy(context->error_msg, "expected an identifier");
  79       return -1;
  80    }
  81
  82    defined = _macro_is_defined(context, input.data.identifier);
  83
  84    if (parens) {
  85       if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  86          return -1;
  87       }
  88       if (input.token != SL_PP_RPAREN) {
  89          strcpy(context->error_msg, "expected `)'");
  90          return -1;
  91       }
  92    }
  93
  94    result.token = SL_PP_UINT;
  95    result.data._uint = (defined ? context->dict._1 : context->dict._0);
  96
  97    if (sl_pp_process_out(state, &result)) {
  98       strcpy(context->error_msg, "out of memory");
  99       return -1;
 100    }
 101
 102    return 0;
 103 }
 104
 105 static unsigned int
 106 _evaluate_if_stack(struct sl_pp_context *context)
 107 {
 108    unsigned int i;
 109
 110    for (i = context->if_ptr; i < SL_PP_MAX_IF_NESTING; i++) {
 111       if (!(context->if_stack[i] & 1)) {
 112          return 0;
 113       }
 114    }
 115    return 1;
 116 }
 117
 118 static int
 119 _parse_if(struct sl_pp_context *context,
 120           struct sl_pp_token_buffer *buffer)
 121 {
 122    struct sl_pp_process_state state;
 123    int found_end = 0;
 124    struct sl_pp_token_info eof;
 125    int result;
 126
 127    if (!context->if_ptr) {
 128       strcpy(context->error_msg, "`#if' nesting too deep");
 129       return -1;
 130    }
 131
 132    memset(&state, 0, sizeof(state));
 133    while (!found_end) {
 134       struct sl_pp_token_info input;
 135
 136       sl_pp_token_buffer_get(buffer, &input);
 137       switch (input.token) {
 138       case SL_PP_WHITESPACE:
 139          break;
 140
 141       case SL_PP_IDENTIFIER:
 142          if (input.data.identifier == context->dict.defined) {
 143             if (_parse_defined(context, buffer, &state)) {
 144                free(state.out);
 145                return -1;
 146             }
 147          } else {
 148             sl_pp_token_buffer_unget(buffer, &input);
 149             if (sl_pp_macro_expand(context, buffer, NULL, &state, sl_pp_macro_expand_unknown_to_0)) {
 150                free(state.out);
 151                return -1;
 152             }
 153          }
 154          break;
 155
 156       case SL_PP_NEWLINE:
 157       case SL_PP_EOF:
 158          found_end = 1;
 159          break;
 160
 161       default:
 162          if (sl_pp_process_out(&state, &input)) {
 163             strcpy(context->error_msg, "out of memory");
 164             free(state.out);
 165             return -1;
 166          }
 167       }
 168    }
 169
 170    eof.token = SL_PP_EOF;
 171    if (sl_pp_process_out(&state, &eof)) {
 172       strcpy(context->error_msg, "out of memory");
 173       free(state.out);
 174       return -1;
 175    }
 176
 177    if (sl_pp_execute_expression(context, state.out, &result)) {
 178       free(state.out);
 179       return -1;
 180    }
 181
 182    free(state.out);
 183
 184    context->if_ptr--;
 185    context->if_stack[context->if_ptr] = result ? 1 : 0;
 186    context->if_value = _evaluate_if_stack(context);
 187
 188    return 0;
 189 }
 190
 191 static int
 192 _parse_else(struct sl_pp_context *context)
 193 {
 194    if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
 195       strcpy(context->error_msg, "no matching `#if'");
 196       return -1;
 197    }
 198
 199    /* Bit b1 indicates we already went through #else. */
 200    if (context->if_stack[context->if_ptr] & 2) {
 201       strcpy(context->error_msg, "no matching `#if'");
 202       return -1;
 203    }
 204
 205    /* Invert current condition value and mark that we are in the #else block. */
 206    context->if_stack[context->if_ptr] = (1 - (context->if_stack[context->if_ptr] & 1)) | 2;
 207    context->if_value = _evaluate_if_stack(context);
 208
 209    return 0;
 210 }
 211
 212 int
 213 sl_pp_process_if(struct sl_pp_context *context,
 214                  struct sl_pp_token_buffer *buffer)
 215 {
 216    return _parse_if(context, buffer);
 217 }
 218
 219 int
 220 sl_pp_process_ifdef(struct sl_pp_context *context,
 221                     const struct sl_pp_token_info *input,
 222                     unsigned int first,
 223                     unsigned int last)
 224 {
 225    unsigned int i;
 226
 227    if (!context->if_ptr) {
 228       strcpy(context->error_msg, "`#if' nesting too deep");
 229       return -1;
 230    }
 231
 232    for (i = first; i < last; i++) {
 233       switch (input[i].token) {
 234       case SL_PP_IDENTIFIER:
 235          context->if_ptr--;
 236          context->if_stack[context->if_ptr] = _macro_is_defined(context, input[i].data.identifier);
 237          context->if_value = _evaluate_if_stack(context);
 238          return 0;
 239
 240       case SL_PP_WHITESPACE:
 241          break;
 242
 243       default:
 244          strcpy(context->error_msg, "expected an identifier");
 245          return -1;
 246       }
 247    }
 248
 249    strcpy(context->error_msg, "expected an identifier");
 250    return -1;
 251 }
 252
 253 int
 254 sl_pp_process_ifndef(struct sl_pp_context *context,
 255                      const struct sl_pp_token_info *input,
 256                      unsigned int first,
 257                      unsigned int last)
 258 {
 259    unsigned int i;
 260
 261    if (!context->if_ptr) {
 262       strcpy(context->error_msg, "`#if' nesting too deep");
 263       return -1;
 264    }
 265
 266    for (i = first; i < last; i++) {
 267       switch (input[i].token) {
 268       case SL_PP_IDENTIFIER:
 269          context->if_ptr--;
 270          context->if_stack[context->if_ptr] = !_macro_is_defined(context, input[i].data.identifier);
 271          context->if_value = _evaluate_if_stack(context);
 272          return 0;
 273
 274       case SL_PP_WHITESPACE:
 275          break;
 276
 277       default:
 278          strcpy(context->error_msg, "expected an identifier");
 279          return -1;
 280       }
 281    }
 282
 283    strcpy(context->error_msg, "expected an identifier");
 284    return -1;
 285 }
 286
 287 int
 288 sl_pp_process_elif(struct sl_pp_context *context,
 289                    struct sl_pp_token_buffer *buffer)
 290 {
 291    if (_parse_else(context)) {
 292       return -1;
 293    }
 294
 295    if (context->if_stack[context->if_ptr] & 1) {
 296       context->if_ptr++;
 297       if (_parse_if(context, buffer)) {
 298          return -1;
 299       }
 300    }
 301
 302    /* We are still in the #if block. */
 303    context->if_stack[context->if_ptr] = context->if_stack[context->if_ptr] & ~2;
 304
 305    return 0;
 306 }
 307
 308 int
 309 sl_pp_process_else(struct sl_pp_context *context,
 310                    const struct sl_pp_token_info *input,
 311                    unsigned int first,
 312                    unsigned int last)
 313 {
 314    return _parse_else(context);
 315 }
 316
 317 int
 318 sl_pp_process_endif(struct sl_pp_context *context,
 319                     const struct sl_pp_token_info *input,
 320                     unsigned int first,
 321                     unsigned int last)
 322 {
 323    if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
 324       strcpy(context->error_msg, "no matching `#if'");
 325       return -1;
 326    }
 327
 328    context->if_ptr++;
 329    context->if_value = _evaluate_if_stack(context);
 330
 331    return 0;
 332 }