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 _parse_defined(struct sl_pp_context *context,
  36                struct sl_pp_token_buffer *buffer,
  37                struct sl_pp_process_state *state)
  38 {
  39    struct sl_pp_token_info input;
  40    int parens = 0;
  41    int macro_name;
  42    struct sl_pp_macro *macro;
  43    int defined = 0;
  44    struct sl_pp_token_info result;
  45
  46    if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  47       return -1;
  48    }
  49
  50    if (input.token == SL_PP_LPAREN) {
  51       if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  52          return -1;
  53       }
  54       parens = 1;
  55    }
  56
  57    if (input.token != SL_PP_IDENTIFIER) {
  58       strcpy(context->error_msg, "expected an identifier");
  59       return -1;
  60    }
  61
  62    macro_name = input.data.identifier;
  63    for (macro = context->macro; macro; macro = macro->next) {
  64       if (macro->name == macro_name) {
  65          defined = 1;
  66          break;
  67       }
  68    }
  69
  70    if (parens) {
  71       if (sl_pp_token_buffer_skip_white(buffer, &input)) {
  72          return -1;
  73       }
  74       if (input.token != SL_PP_RPAREN) {
  75          strcpy(context->error_msg, "expected `)'");
  76          return -1;
  77       }
  78    }
  79
  80    result.token = SL_PP_UINT;
  81    result.data._uint = (defined ? context->dict._1 : context->dict._0);
  82
  83    if (sl_pp_process_out(state, &result)) {
  84       strcpy(context->error_msg, "out of memory");
  85       return -1;
  86    }
  87
  88    return 0;
  89 }
  90
  91 static unsigned int
  92 _evaluate_if_stack(struct sl_pp_context *context)
  93 {
  94    unsigned int i;
  95
  96    for (i = context->if_ptr; i < SL_PP_MAX_IF_NESTING; i++) {
  97       if (!(context->if_stack[i] & 1)) {
  98          return 0;
  99       }
 100    }
 101    return 1;
 102 }
 103
 104 static int
 105 _parse_if(struct sl_pp_context *context,
 106           struct sl_pp_token_buffer *buffer)
 107 {
 108    struct sl_pp_process_state state;
 109    int found_end = 0;
 110    struct sl_pp_token_info eof;
 111    int result;
 112
 113    if (!context->if_ptr) {
 114       strcpy(context->error_msg, "`#if' nesting too deep");
 115       return -1;
 116    }
 117
 118    memset(&state, 0, sizeof(state));
 119    while (!found_end) {
 120       struct sl_pp_token_info input;
 121
 122       sl_pp_token_buffer_get(buffer, &input);
 123       switch (input.token) {
 124       case SL_PP_WHITESPACE:
 125          break;
 126
 127       case SL_PP_IDENTIFIER:
 128          if (input.data.identifier == context->dict.defined) {
 129             if (_parse_defined(context, buffer, &state)) {
 130                free(state.out);
 131                return -1;
 132             }
 133          } else {
 134             sl_pp_token_buffer_unget(buffer, &input);
 135             if (sl_pp_macro_expand(context, buffer, NULL, &state, sl_pp_macro_expand_unknown_to_0)) {
 136                free(state.out);
 137                return -1;
 138             }
 139          }
 140          break;
 141
 142       case SL_PP_NEWLINE:
 143       case SL_PP_EOF:
 144          found_end = 1;
 145          break;
 146
 147       default:
 148          if (sl_pp_process_out(&state, &input)) {
 149             strcpy(context->error_msg, "out of memory");
 150             free(state.out);
 151             return -1;
 152          }
 153       }
 154    }
 155
 156    eof.token = SL_PP_EOF;
 157    if (sl_pp_process_out(&state, &eof)) {
 158       strcpy(context->error_msg, "out of memory");
 159       free(state.out);
 160       return -1;
 161    }
 162
 163    if (sl_pp_execute_expression(context, state.out, &result)) {
 164       free(state.out);
 165       return -1;
 166    }
 167
 168    free(state.out);
 169
 170    context->if_ptr--;
 171    context->if_stack[context->if_ptr] = result ? 1 : 0;
 172    context->if_value = _evaluate_if_stack(context);
 173
 174    return 0;
 175 }
 176
 177 static int
 178 _parse_else(struct sl_pp_context *context)
 179 {
 180    if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
 181       strcpy(context->error_msg, "no matching `#if'");
 182       return -1;
 183    }
 184
 185    /* Bit b1 indicates we already went through #else. */
 186    if (context->if_stack[context->if_ptr] & 2) {
 187       strcpy(context->error_msg, "no matching `#if'");
 188       return -1;
 189    }
 190
 191    /* Invert current condition value and mark that we are in the #else block. */
 192    context->if_stack[context->if_ptr] = (1 - (context->if_stack[context->if_ptr] & 1)) | 2;
 193    context->if_value = _evaluate_if_stack(context);
 194
 195    return 0;
 196 }
 197
 198 int
 199 sl_pp_process_if(struct sl_pp_context *context,
 200                  struct sl_pp_token_buffer *buffer)
 201 {
 202    return _parse_if(context, buffer);
 203 }
 204
 205 int
 206 sl_pp_process_ifdef(struct sl_pp_context *context,
 207                     const struct sl_pp_token_info *input,
 208                     unsigned int first,
 209                     unsigned int last)
 210 {
 211    unsigned int i;
 212
 213    if (!context->if_ptr) {
 214       strcpy(context->error_msg, "`#if' nesting too deep");
 215       return -1;
 216    }
 217
 218    for (i = first; i < last; i++) {
 219       switch (input[i].token) {
 220       case SL_PP_IDENTIFIER:
 221          {
 222             struct sl_pp_macro *macro;
 223             int macro_name = input[i].data.identifier;
 224             int defined = 0;
 225
 226             for (macro = context->macro; macro; macro = macro->next) {
 227                if (macro->name == macro_name) {
 228                   defined = 1;
 229                   break;
 230                }
 231             }
 232
 233             context->if_ptr--;
 234             context->if_stack[context->if_ptr] = defined ? 1 : 0;
 235             context->if_value = _evaluate_if_stack(context);
 236          }
 237          return 0;
 238
 239       case SL_PP_WHITESPACE:
 240          break;
 241
 242       default:
 243          strcpy(context->error_msg, "expected an identifier");
 244          return -1;
 245       }
 246    }
 247
 248    strcpy(context->error_msg, "expected an identifier");
 249    return -1;
 250 }
 251
 252 int
 253 sl_pp_process_ifndef(struct sl_pp_context *context,
 254                      const struct sl_pp_token_info *input,
 255                      unsigned int first,
 256                      unsigned int last)
 257 {
 258    unsigned int i;
 259
 260    if (!context->if_ptr) {
 261       strcpy(context->error_msg, "`#if' nesting too deep");
 262       return -1;
 263    }
 264
 265    for (i = first; i < last; i++) {
 266       switch (input[i].token) {
 267       case SL_PP_IDENTIFIER:
 268          {
 269             struct sl_pp_macro *macro;
 270             int macro_name = input[i].data.identifier;
 271             int defined = 0;
 272
 273             for (macro = context->macro; macro; macro = macro->next) {
 274                if (macro->name == macro_name) {
 275                   defined = 1;
 276                   break;
 277                }
 278             }
 279
 280             context->if_ptr--;
 281             context->if_stack[context->if_ptr] = defined ? 0 : 1;
 282             context->if_value = _evaluate_if_stack(context);
 283          }
 284          return 0;
 285
 286       case SL_PP_WHITESPACE:
 287          break;
 288
 289       default:
 290          strcpy(context->error_msg, "expected an identifier");
 291          return -1;
 292       }
 293    }
 294
 295    strcpy(context->error_msg, "expected an identifier");
 296    return -1;
 297 }
 298
 299 int
 300 sl_pp_process_elif(struct sl_pp_context *context,
 301                    struct sl_pp_token_buffer *buffer)
 302 {
 303    if (_parse_else(context)) {
 304       return -1;
 305    }
 306
 307    if (context->if_stack[context->if_ptr] & 1) {
 308       context->if_ptr++;
 309       if (_parse_if(context, buffer)) {
 310          return -1;
 311       }
 312    }
 313
 314    /* We are still in the #if block. */
 315    context->if_stack[context->if_ptr] = context->if_stack[context->if_ptr] & ~2;
 316
 317    return 0;
 318 }
 319
 320 int
 321 sl_pp_process_else(struct sl_pp_context *context,
 322                    const struct sl_pp_token_info *input,
 323                    unsigned int first,
 324                    unsigned int last)
 325 {
 326    return _parse_else(context);
 327 }
 328
 329 int
 330 sl_pp_process_endif(struct sl_pp_context *context,
 331                     const struct sl_pp_token_info *input,
 332                     unsigned int first,
 333                     unsigned int last)
 334 {
 335    if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
 336       strcpy(context->error_msg, "no matching `#if'");
 337       return -1;
 338    }
 339
 340    context->if_ptr++;
 341    context->if_value = _evaluate_if_stack(context);
 342
 343    return 0;
 344 }