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 <limits.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <ctype.h>
  27 #include "gmqcc.h"
  28
  29 /* compile-time constant for type constants */
  30 typedef struct {
  31         char *name;
  32         int   type;
  33         float value[3];
  34         char *string; /* string value if constant is string literal */
  35 } constant;
  36 VECTOR_MAKE(constant, compile_constants);
  37
  38 /*
  39  * Generates a parse tree out of the lexees generated by the lexer.  This
  40  * is where the tree is built.  This is where valid check is performed.
  41  */
  42 int parse_gen(struct lex_file *file) {
  43         int     token = 0;
  44         while ((token = lex_token(file)) != ERROR_LEX      && \
  45                     token                    != ERROR_COMPILER && \
  46                     token                    != ERROR_INTERNAL && \
  47                     token                    != ERROR_PARSE    && \
  48                     token                    != ERROR_PREPRO   && file->length >= 0) {
  49                 switch (token) {
  50                         case TOKEN_TYPEDEF: {
  51                                 char *f; /* from */
  52                                 char *t; /* to   */
  53
  54                                 token = lex_token(file);
  55                                 token = lex_token(file); f = util_strdup(file->lastok);
  56                                 token = lex_token(file);
  57                                 token = lex_token(file); t = util_strdup(file->lastok);
  58
  59                                 typedef_add(f, t);
  60                                 mem_d(f);
  61                                 mem_d(t);
  62
  63                                 token = lex_token(file);
  64                                 if (token == ' ')
  65                                         token = lex_token(file);
  66
  67                                 if (token != ';')
  68                                         error(ERROR_PARSE, "%s:%d Expected a `;` at end of typedef statement\n", file->name, file->line);
  69
  70                                 token = lex_token(file);
  71                                 break;
  72                         }
  73
  74                         case TOKEN_VOID:   goto fall;
  75                         case TOKEN_STRING: goto fall;
  76                         case TOKEN_VECTOR: goto fall;
  77                         case TOKEN_ENTITY: goto fall;
  78                         case TOKEN_FLOAT:  goto fall;
  79                         {
  80                         fall:;
  81                                 char *name = NULL;
  82                                 int   type = token; /* story copy */
  83
  84                                 /* skip over space */
  85                                 token = lex_token(file);
  86                                 if (token == ' ')
  87                                         token = lex_token(file);
  88
  89                                 /* save name */
  90                                 name = util_strdup(file->lastok);
  91
  92                                 /* skip spaces */
  93                                 token = lex_token(file);
  94                                 if (token == ' ')
  95                                         token = lex_token(file);
  96
  97                                 if (token == ';') {
  98                                         /*
  99                                          * Definitions go to the defs table, they don't have
 100                                          * any sort of data with them yet.
 101                                          */
 102                                 } else if (token == '=') {
 103                                         token = lex_token(file);
 104                                         if (token == ' ')
 105                                                 token = lex_token(file);
 106
 107                                         /* strings are in file->lastok */
 108                                         switch (type) {
 109                                                 case TOKEN_VOID:
 110                                                         return error(ERROR_PARSE, "%s:%d Cannot assign value to type void\n", file->name, file->line);
 111
 112                                                 /* TODO: Validate (end quote), strip quotes for constant add, name constant */
 113                                                 case TOKEN_STRING:
 114                                                         if (*file->lastok != '"')
 115                                                                 error(ERROR_PARSE, "%s:%d Expected a '\"' (quote) for string constant\n", file->name, file->line);
 116                                                         /* add the compile-time constant */
 117                                                         compile_constants_add((constant){
 118                                                                 .name   = util_strdup(name),
 119                                                                 .type   = TYPE_STRING,
 120                                                                 .value  = {0,0,0},
 121                                                                 .string = util_strdup(file->lastok)
 122                                                         });
 123                                                         break;
 124                                                 /* TODO: name constant, old qc vec literals, whitespace fixes, name constant */
 125                                                 case TOKEN_VECTOR: {
 126                                                         float compile_calc_x = 0;
 127                                                         float compile_calc_y = 0;
 128                                                         float compile_calc_z = 0;
 129                                                         int   compile_calc_d = 0; /* dot?        */
 130                                                         int   compile_calc_s = 0; /* sign (-, +) */
 131
 132                                                         char  compile_data[1024];
 133                                                         char *compile_eval = compile_data;
 134
 135                                                         if (token != '{')
 136                                                                 error(ERROR_PARSE, "%s:%d Expected initializer list `{`,`}` for vector constant\n", file->name, file->line);
 137
 138                                                         /*
 139                                                          * This parses a single vector element: x,y & z.  This will handle all the
 140                                                          * complicated mechanics of a vector, and can be extended as well.  This
 141                                                          * is a rather large macro, and is #undef'd after it's use below.
 142                                                          */
 143                                                         #define PARSE_VEC_ELEMENT(NAME, BIT)                                                                                                                                   \
 144                                                             token = lex_token(file);                                                                                                                                           \
 145                                                             if (token == ' ')                                                                                                                                                  \
 146                                                                 token = lex_token(file);                                                                                                                                       \
 147                                                             if (token == '.')                                                                                                                                                  \
 148                                                                 compile_calc_d = 1;                                                                                                                                            \
 149                                                             if (!isdigit(token) && !compile_calc_d && token != '+' && token != '-')                                                                                            \
 150                                                                 error(ERROR_PARSE,"%s:%d Invalid constant initializer element %c for vector, must be numeric\n", file->name, file->line, NAME);                                \
 151                                                             if (token == '+')                                                                                                                                                  \
 152                                                                 compile_calc_s = '+';                                                                                                                                          \
 153                                                             if (token == '-' && !compile_calc_s)                                                                                                                               \
 154                                                                 compile_calc_s = '-';                                                                                                                                          \
 155                                                             while (isdigit(token) || token == '.' || token == '+' || token == '-') {                                                                                           \
 156                                                                 *compile_eval++ = token;                                                                                                                                       \
 157                                                                 token           = lex_token(file);                                                                                                                             \
 158                                                                 if (token == '.' && compile_calc_d) {                                                                                                                          \
 159                                                                     error(ERROR_PARSE, "%s:%d Invalid constant initializer element %c for vector, must be numeric.\n", file->name, file->line, NAME);                          \
 160                                                                     token = lex_token(file);                                                                                                                                   \
 161                                                                 }                                                                                                                                                              \
 162                                                                 if ((token == '-' || token == '+') && compile_calc_s) {                                                                                                        \
 163                                                                     error(ERROR_PARSE, "%s:%d Invalid constant initializer sign for vector element %c\n", file->name, file->line, NAME);                                       \
 164                                                                     token = lex_token(file);                                                                                                                                   \
 165                                                                 }                                                                                                                                                              \
 166                                                                 else if (token == '.' && !compile_calc_d)                                                                                                                      \
 167                                                                     compile_calc_d = 1;                                                                                                                                        \
 168                                                                 else if (token == '-' && !compile_calc_s)                                                                                                                      \
 169                                                                     compile_calc_s = '-';                                                                                                                                      \
 170                                                                 else if (token == '+' && !compile_calc_s)                                                                                                                      \
 171                                                                     compile_calc_s = '+';                                                                                                                                      \
 172                                                             }                                                                                                                                                                  \
 173                                                             if (token == ' ')                                                                                                                                                  \
 174                                                                 token = lex_token(file);                                                                                                                                       \
 175                                                             if (NAME != 'z') {                                                                                                                                                 \
 176                                                                 if (token != ',' && token != ' ')                                                                                                                              \
 177                                                                     error(ERROR_PARSE, "%s:%d invalid constant initializer element %c for vector (missing spaces, or comma delimited list?)\n", file->name, file->line, NAME); \
 178                                                             } else if (token != '}') {                                                                                                                                         \
 179                                                                 error(ERROR_PARSE, "%s:%d Expected `}` on end of constant initialization for vector\n", file->name, file->line);                                               \
 180                                                             }                                                                                                                                                                  \
 181                                                             compile_calc_##BIT = atof(compile_data);                                                                                                                           \
 182                                                             compile_calc_d = 0;                                                                                                                                                \
 183                                                             compile_calc_s = 0;                                                                                                                                                \
 184                                                             compile_eval   = &compile_data[0];                                                                                                                                 \
 185                                                             memset(compile_data, 0, sizeof(compile_data))
 186
 187                                                         /*
 188                                                          * Parse all elements using the macro above.
 189                                                          * We must undef the macro afterwards.
 190                                                          */
 191                                                         PARSE_VEC_ELEMENT('x', x);
 192                                                         PARSE_VEC_ELEMENT('y', y);
 193                                                         PARSE_VEC_ELEMENT('z', z);
 194                                                         #undef PARSE_VEC_ELEMENT
 195
 196                                                         /* Check for the semi-colon... */
 197                                                         token = lex_token(file);
 198                                                         if (token == ' ')
 199                                                                 token = lex_token(file);
 200                                                         if (token != ';')
 201                                                                 error(ERROR_PARSE, "%s:%d Expected `;` on end of constant initialization for vector\n", file->name, file->line);
 202
 203                                                         /* add the compile-time constant */
 204                                                         compile_constants_add((constant){
 205                                                                 .name   = util_strdup(name),
 206                                                                 .type   = TYPE_VECTOR,
 207                                                                 .value  = {
 208                                                                         [0] = compile_calc_x,
 209                                                                         [1] = compile_calc_y,
 210                                                                         [2] = compile_calc_z
 211                                                                 },
 212                                                                 .string = NULL
 213                                                         });
 214                                                         break;
 215                                                 }
 216
 217                                                 case TOKEN_ENTITY:
 218                                                 case TOKEN_FLOAT: /*TODO: validate, constant generation, name constant */
 219                                                         if (!isdigit(token))
 220                                                                 error(ERROR_PARSE, "%s:%d Expected numeric constant for float constant\n");
 221                                                         compile_constants_add((constant){
 222                                                                 .name   = util_strdup(name),
 223                                                                 .type   = TOKEN_FLOAT,
 224                                                                 .value  = {0,0,0},
 225                                                                 .string = NULL
 226                                                         });
 227                                                         break;
 228                                         }
 229                                 } else if (token == '(') {
 230                                         printf("FUNCTION ??\n");
 231                                 }
 232                                 mem_d(name);
 233                         }
 234
 235                         /*
 236                          * From here down is all language punctuation:  There is no
 237                          * need to actual create tokens from these because they're already
 238                          * tokenized as these individual tokens (which are in a special area
 239                          * of the ascii table which doesn't conflict with our other tokens
 240                          * which are higer than the ascii table.)
 241                          */
 242                         case '#':
 243                                 token = lex_token(file); /* skip '#' */
 244                                 if (token == ' ')
 245                                         token = lex_token(file);
 246                                 /*
 247                                  * If we make it here we found a directive, the supported
 248                                  * directives so far are #include.
 249                                  */
 250                                 if (strncmp(file->lastok, "include", sizeof("include")) == 0) {
 251                                         /*
 252                                          * We only suport include " ", not <> like in C (why?)
 253                                          * because the latter is silly.
 254                                          */
 255                                         while (*file->lastok != '"' && token != '\n')
 256                                                 token = lex_token(file);
 257                                         if (token == '\n')
 258                                                 return error(ERROR_PARSE, "%d: Invalid use of include preprocessor directive: wanted #include \"file.h\"\n", file->line-1);
 259
 260                                         char            *copy = util_strdup(file->lastok);
 261                                         struct lex_file *next = lex_include(file,   copy);
 262
 263                                         if (!next) {
 264                                                 error(ERROR_INTERNAL, "Include subsystem failure\n");
 265                                                 exit (-1);
 266                                         }
 267                                         parse_gen(next);
 268                                         mem_d    (copy);
 269                                         lex_close(next);
 270                                 }
 271                                 /* skip all tokens to end of directive */
 272                                 while (token != '\n')
 273                                         token = lex_token(file);
 274                                 break;
 275
 276                         case LEX_IDENT:
 277                                 token = lex_token(file);
 278                                 break;
 279                 }
 280         }
 281         lex_reset(file);
 282         return 1;
 283 }