parse.c

   1 /*
   2  * Copyright (C) 2012
   3  *     Dale Weiler
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
   6  * this software and associated documentation files (the "Software"), to deal in
   7  * the Software without restriction, including without limitation the rights to
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is furnished to do
  10  * so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in all
  13  * copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23 #include "gmqcc.h"
  24
  25 /* compile-time constant for type constants */
  26 typedef struct {
  27     char *name;
  28     int   type;
  29     float value[3];
  30     char *string; /* string value if constant is string literal */
  31 } constant;
  32 VECTOR_MAKE(constant, compile_constants);
  33
  34 void compile_constant_debug() {
  35     int iter = 0;
  36     for(; iter < compile_constants_elements; iter++) {
  37         constant *c = &compile_constants_data[iter];
  38         switch(c->type) {
  39             case TYPE_FLOAT:  printf("constant: %s FLOAT   %f\n",       c->name, c->value[0]);                           break;
  40             case TYPE_VECTOR: printf("constant: %s VECTOR {%f,%f,%f}\n",c->name, c->value[0], c->value[1], c->value[2]); break;
  41             case TYPE_STRING: printf("constant: %s STRING  %s\n",       c->name, c->string); break;
  42             case TYPE_VOID:   printf("constant: %s VOID    %s\n",       c->name, c->string); break;
  43         }
  44     }
  45 }
  46
  47 /*
  48  * Generates a parse tree out of the lexees generated by the lexer.  This
  49  * is where the tree is built.  This is where valid check is performed.
  50  */
  51 int parse_gen(lex_file *file) {
  52     int     token = 0;
  53     while ((token = lex_token(file)) != ERROR_LEX && file->length >= 0) {
  54         switch (token) {
  55             case TOKEN_TYPEDEF: {
  56                 char *f; /* from */
  57                 char *t; /* to   */
  58
  59                 token = lex_token(file);
  60                 token = lex_token(file); f = util_strdup(file->lastok);
  61                 token = lex_token(file);
  62                 token = lex_token(file); t = util_strdup(file->lastok);
  63
  64                 typedef_add(file, f, t);
  65                 mem_d(f);
  66                 mem_d(t);
  67
  68                 token = lex_token(file);
  69                 if (token == ' ')
  70                     token = lex_token(file);
  71
  72                 if (token != ';')
  73                     error(file, ERROR_PARSE, "Expected a `;` at end of typedef statement");
  74
  75                 token = lex_token(file);
  76                 break;
  77             }
  78
  79             case TOKEN_VOID:   goto fall;
  80             case TOKEN_STRING: goto fall;
  81             case TOKEN_VECTOR: goto fall;
  82             case TOKEN_ENTITY: goto fall;
  83             case TOKEN_FLOAT:  goto fall;
  84             {
  85             fall:;
  86                 char *name = NULL;
  87                 int   type = token; /* story copy */
  88
  89                 /* skip over space */
  90                 token = lex_token(file);
  91                 if (token == ' ')
  92                     token = lex_token(file);
  93
  94                 /* save name */
  95                 name = util_strdup(file->lastok);
  96
  97                 /* skip spaces */
  98                 token = lex_token(file);
  99                 if (token == ' ')
 100                     token = lex_token(file);
 101
 102                 if (token == ';') {
 103                     /*
 104                      * Definitions go to the defs table, they don't have
 105                      * any sort of data with them yet.
 106                      */
 107                 } else if (token == '=') {
 108                     token = lex_token(file);
 109                     if (token == ' ')
 110                         token = lex_token(file);
 111
 112                     /* strings are in file->lastok */
 113                     switch (type) {
 114                         case TOKEN_VOID:
 115                             error(file, ERROR_PARSE, "Cannot assign value to type void\n");
 116
 117                         /* TODO: Validate (end quote), strip quotes for constant add, name constant */
 118                         case TOKEN_STRING:
 119                             if (*file->lastok != '"')
 120                                 error(file, ERROR_PARSE, "Expected a '\"' (quote) for string constant\n");
 121                             /* add the compile-time constant */
 122                             compile_constants_add((constant){
 123                                 .name   = util_strdup(name),
 124                                 .type   = TYPE_STRING,
 125                                 .value  = {0,0,0},
 126                                 .string = util_strdup(file->lastok)
 127                             });
 128                             break;
 129                         /* TODO: name constant, old qc vec literals, whitespace fixes, name constant */
 130                         case TOKEN_VECTOR: {
 131                             float compile_calc_x = 0;
 132                             float compile_calc_y = 0;
 133                             float compile_calc_z = 0;
 134                             int   compile_calc_d = 0; /* dot?        */
 135                             int   compile_calc_s = 0; /* sign (-, +) */
 136
 137                             char  compile_data[1024];
 138                             char *compile_eval = compile_data;
 139
 140                             if (token != '{')
 141                                 error(file, ERROR_PARSE, "Expected initializer list {} for vector constant\n");
 142
 143                             /*
 144                              * This parses a single vector element: x,y & z.  This will handle all the
 145                              * complicated mechanics of a vector, and can be extended as well.  This
 146                              * is a rather large macro, and is #undef'd after it's use below.
 147                              */
 148                             #define PARSE_VEC_ELEMENT(NAME, BIT)                                                                                                           \
 149                                 token = lex_token(file);                                                                                                                   \
 150                                 if (token == ' ')                                                                                                                          \
 151                                     token = lex_token(file);                                                                                                               \
 152                                 if (token == '.')                                                                                                                          \
 153                                     compile_calc_d = 1;                                                                                                                    \
 154                                 if (!isdigit(token) && !compile_calc_d && token != '+' && token != '-')                                                                    \
 155                                     error(file, ERROR_PARSE,"Invalid constant initializer element %c for vector, must be numeric\n", NAME);                                \
 156                                 if (token == '+')                                                                                                                          \
 157                                     compile_calc_s = '+';                                                                                                                  \
 158                                 if (token == '-' && !compile_calc_s)                                                                                                       \
 159                                     compile_calc_s = '-';                                                                                                                  \
 160                                 while (isdigit(token) || token == '.' || token == '+' || token == '-') {                                                                   \
 161                                     *compile_eval++ = token;                                                                                                               \
 162                                     token           = lex_token(file);                                                                                                     \
 163                                     if (token == '.' && compile_calc_d) {                                                                                                  \
 164                                         error(file, ERROR_PARSE, "Invalid constant initializer element %c for vector, must be numeric.\n", NAME);                          \
 165                                         token = lex_token(file);                                                                                                           \
 166                                     }                                                                                                                                      \
 167                                     if ((token == '-' || token == '+') && compile_calc_s) {                                                                                \
 168                                         error(file, ERROR_PARSE, "Invalid constant initializer sign for vector element %c\n", NAME);                                       \
 169                                         token = lex_token(file);                                                                                                           \
 170                                     }                                                                                                                                      \
 171                                     else if (token == '.' && !compile_calc_d)                                                                                              \
 172                                         compile_calc_d = 1;                                                                                                                \
 173                                     else if (token == '-' && !compile_calc_s)                                                                                              \
 174                                         compile_calc_s = '-';                                                                                                              \
 175                                     else if (token == '+' && !compile_calc_s)                                                                                              \
 176                                         compile_calc_s = '+';                                                                                                              \
 177                                 }                                                                                                                                          \
 178                                 if (token == ' ')                                                                                                                          \
 179                                     token = lex_token(file);                                                                                                               \
 180                                 if (NAME != 'z') {                                                                                                                         \
 181                                     if (token != ',' && token != ' ')                                                                                                      \
 182                                         error(file, ERROR_PARSE, "invalid constant initializer element %c for vector (missing spaces, or comma delimited list?)\n", NAME); \
 183                                 } else if (token != '}') {                                                                                                                 \
 184                                     error(file, ERROR_PARSE, "Expected `}` on end of constant initialization for vector\n");                                               \
 185                                 }                                                                                                                                          \
 186                                 compile_calc_##BIT = atof(compile_data);                                                                                                   \
 187                                 compile_calc_d = 0;                                                                                                                        \
 188                                 compile_calc_s = 0;                                                                                                                        \
 189                                 compile_eval   = &compile_data[0];                                                                                                         \
 190                                 memset(compile_data, 0, sizeof(compile_data))
 191
 192                             /*
 193                              * Parse all elements using the macro above.
 194                              * We must undef the macro afterwards.
 195                              */
 196                             PARSE_VEC_ELEMENT('x', x);
 197                             PARSE_VEC_ELEMENT('y', y);
 198                             PARSE_VEC_ELEMENT('z', z);
 199                             #undef PARSE_VEC_ELEMENT
 200
 201                             /* Check for the semi-colon... */
 202                             token = lex_token(file);
 203                             if (token == ' ')
 204                                 token = lex_token(file);
 205                             if (token != ';')
 206                                 error(file, ERROR_PARSE, "Expected `;` on end of constant initialization for vector\n");
 207
 208                             /* add the compile-time constant */
 209                             compile_constants_add((constant){
 210                                 .name   = util_strdup(name),
 211                                 .type   = TYPE_VECTOR,
 212                                 .value  = {
 213                                     [0] = compile_calc_x,
 214                                     [1] = compile_calc_y,
 215                                     [2] = compile_calc_z
 216                                 },
 217                                 .string = NULL
 218                             });
 219                             break;
 220                         }
 221
 222                         case TOKEN_ENTITY:
 223                         case TOKEN_FLOAT: /*TODO: validate, constant generation, name constant */
 224                             if (!isdigit(token))
 225                                 error(file, ERROR_PARSE, "Expected numeric constant for float constant\n");
 226                             compile_constants_add((constant){
 227                                 .name   = util_strdup(name),
 228                                 .type   = TOKEN_FLOAT,
 229                                 .value  = {0,0,0},
 230                                 .string = NULL
 231                             });
 232                             break;
 233                     }
 234                 } else if (token == '(') {
 235                     printf("FUNCTION ??\n");
 236                 }
 237                 mem_d(name);
 238             }
 239
 240             /*
 241              * From here down is all language punctuation:  There is no
 242              * need to actual create tokens from these because they're already
 243              * tokenized as these individual tokens (which are in a special area
 244              * of the ascii table which doesn't conflict with our other tokens
 245              * which are higer than the ascii table.)
 246              */
 247             case '#':
 248                 token = lex_token(file); /* skip '#' */
 249                 if (token == ' ')
 250                     token = lex_token(file);
 251                 /*
 252                  * If we make it here we found a directive, the supported
 253                  * directives so far are #include.
 254                  */
 255                 if (strncmp(file->lastok, "include", sizeof("include")) == 0) {
 256                     /*
 257                      * We only suport include " ", not <> like in C (why?)
 258                      * because the latter is silly.
 259                      */
 260                     while (*file->lastok != '"' && token != '\n')
 261                         token = lex_token(file);
 262                     if (token == '\n')
 263                         return error(file, ERROR_PARSE, "Invalid use of include preprocessor directive: wanted #include \"file.h\"\n");
 264
 265                     char      *copy = util_strdup(file->lastok);
 266                     lex_file  *next = lex_include(file,   copy);
 267
 268                     if (!next) {
 269                         error(file, ERROR_INTERNAL, "Include subsystem failure\n");
 270                         exit (-1);
 271                     }
 272                     compile_constants_add((constant) {
 273                             .name   = "#include",
 274                             .type   = TYPE_VOID,
 275                             .value  = {0,0,0},
 276                             .string = copy
 277                     });
 278                     parse_gen(next);
 279                     mem_d    (copy);
 280                     lex_close(next);
 281                 }
 282                 /* skip all tokens to end of directive */
 283                 while (token != '\n')
 284                     token = lex_token(file);
 285                 break;
 286
 287             case LEX_IDENT:
 288                 token = lex_token(file);
 289                 break;
 290         }
 291     }
 292     compile_constant_debug();
 293     lex_reset(file);
 294     /* free constants */
 295     {
 296                 size_t i = 0;
 297                 for (; i < compile_constants_elements; i++) {
 298                         mem_d(compile_constants_data[i].name);
 299                         mem_d(compile_constants_data[i].string);
 300                 }
 301                 mem_d(compile_constants_data);
 302         }
 303     return 1;
 304 }