src/parser.lex

   1 %{
   2
   3 #include <string.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include "q.h"
   7 #include "parser.h"
   8
   9 //RVALUE         {NUMBER}|{PERCENT}|{NAME}|\"{STRING}\"|{DIM}
  10 //<a>.                {printf("<a>%s\n", yytext);}
  11 // %x: exclusive, %s: inclusive
  12 char*type_names[] = {"twip","number","command","string","assignment","identifier","label","end"};
  13 static int line=1;
  14 static int column=1;
  15
  16 mem_t strings;
  17 mem_t tokens;
  18
  19 static void count(char*text, int len, int condition)
  20 {
  21     int t;
  22     for(t=0;t<len;t++) {
  23         if(text[t]=='\n') {
  24             line++;
  25             column=1;
  26         } else {
  27             column++;
  28         }
  29     }
  30 }
  31
  32 static char*prefix = 0;
  33
  34 static void unescapeString(string_t * tmp)
  35 {
  36     char *p, *p1;
  37     /* fixme - this routine expects the string to be
  38        null-terminated */
  39
  40     for (p1=tmp->str; (p=strchr(p1, '\\')); p1 = p+1)
  41     {
  42         switch(p[1])
  43         {
  44             case '\\': p[1] = '\\'; tmp->len--; break;
  45             case '"': p[1] = '"'; tmp->len--; break;
  46             case 'b': p[1] = '\b'; tmp->len--; break;
  47             case 'f': p[1] = '\f'; tmp->len--; break;
  48             case 'n': p[1] = '\n'; tmp->len--; break;
  49             case 'r': p[1] = '\r'; tmp->len--; break;
  50             case 't': p[1] = '\t'; tmp->len--; break;
  51             default:
  52                 continue;
  53         }
  54         strcpy(p, p+1);
  55     }
  56 }
  57
  58 static void store(enum type_t type, int line, int column, char*text, int length)
  59 {
  60     struct token_t token;
  61     string_t tmp;
  62     token.type = type;
  63     token.line = line;
  64     token.column = column;
  65     //printf("->%d(%s) %s\n", type, type_names[type], text);fflush(stdout);
  66
  67     token.text = 0;
  68     switch(type) {
  69         case END:
  70             string_set2(&tmp, "", 0);
  71             token.text = (char*)mem_putstring(&strings, tmp);
  72         break;
  73         case STRING:
  74             string_set2(&tmp, text+1, length-2);
  75             unescapeString(&tmp);
  76             token.text = (char*)mem_putstring(&strings, tmp);
  77         break;
  78         case TWIP:
  79         case NUMBER:
  80         case IDENTIFIER:
  81             string_set2(&tmp, text, length);
  82             if(prefix) {
  83                 //strcat
  84                 token.text = (char*)mem_put(&strings, prefix, strlen(prefix));
  85                 mem_putstring(&strings, tmp);
  86             } else {
  87                 token.text = (char*)mem_putstring(&strings, tmp);
  88             }
  89             prefix = 0;
  90         break;
  91         case LABEL:
  92             string_set2(&tmp, text, length-1);
  93             token.text = (char*)mem_putstring(&strings, tmp);
  94         break;
  95         case COMMAND:
  96             string_set2(&tmp, text+1, length-1);
  97             token.text = (char*)mem_putstring(&strings, tmp);
  98         break;
  99         case ASSIGNMENT: {
 100             char*x = &text[length-1];
 101             if(x[-1] == '-' || x[-1] == '+')
 102                 x--;
 103             do{x--;} while(*x==32 || *x==10 || *x==13 || *x=='\t');
 104             x++; //first space
 105             string_set2(&tmp, text, x-text);
 106             token.text = (char*)mem_putstring(&strings, tmp);
 107             /*char*y,*x = strchr(text, '=');
 108             if(!x) exit(1);
 109             y=x;
 110             do{y--;} while(*y==32 || *y==10 || *y==13 || *y=='\t');
 111             do{x++;} while(*x==32 || *x==10 || *x==13 || *x=='\t');
 112             token.text1 = (char*)put(&strings, text, y-text + 1, 1);
 113             token.text2 = (char*)put(&strings, x, length-(x-text), 1);*/
 114         } break;
 115     }
 116
 117     mem_put(&tokens, &token, sizeof(struct token_t));
 118     prefix = 0;
 119 }
 120
 121 #define MAX_INCLUDE_DEPTH 16
 122 YY_BUFFER_STATE include_stack[MAX_INCLUDE_DEPTH];
 123 int line_stack[MAX_INCLUDE_DEPTH];
 124 int column_stack[MAX_INCLUDE_DEPTH];
 125 int include_stack_ptr = 0;
 126
 127 void handleInclude(char*text, int len)
 128 {
 129     text+=9;len-=9;
 130     while(len >=1 && (text[0] == ' ' || text[0] == '\t')) {
 131         text++;len--;
 132     }
 133     while(len >= 1 && (text[len-1] == ' ' || text[len-1] == '\n')) {
 134         len--;
 135     }
 136     if(len >= 2 && text[0] == '"' && text[len-1] == '"') {
 137         text++; len-=2;
 138     }
 139     text[len] = 0;
 140     if(include_stack_ptr >= MAX_INCLUDE_DEPTH) {
 141         fprintf( stderr, "Includes nested too deeply" );
 142         exit( 1 );
 143     }
 144     include_stack[include_stack_ptr] = YY_CURRENT_BUFFER;
 145     line_stack[include_stack_ptr] = line;
 146     column_stack[include_stack_ptr] = column;
 147     include_stack_ptr++;
 148     yyin = fopen(text, "rb");
 149     if (!yyin) {
 150         fprintf(stderr, "Couldn't open %s\n", text);
 151         exit(1);
 152     }
 153     yy_switch_to_buffer(
 154         yy_create_buffer( yyin, YY_BUF_SIZE ) );
 155     BEGIN(INITIAL);
 156 }
 157
 158 #define c() {count(yytext, yyleng, YY_START);}
 159 #define s(type) {store(type, line, column, yytext, yyleng);}
 160 %}
 161
 162 %s R
 163 %x BINARY
 164
 165 NAME     [a-zA-Z_./](-*[a-zA-Z0-9_./])*
 166 TWIP     ([0-9]+(\.([0-9]([05])?)?)?)
 167 NUMBER   [0-9]+(\.[0-9]*)?
 168 PERCENT  {NUMBER}%
 169 STRING   (\\.|[^\\"\n])*
 170 S        [ \n\r\t]
 171 RVALUE   \"{STRING}\"|([^ \n\r\t]+)
 172
 173 %%
 174
 175 <BINARY>\] {c();BEGIN(0);}
 176 <BINARY>.  {c();}
 177 <BINARY>\n {c();}
 178 {TWIP}/[ \n\r\t]            {s(TWIP);c();BEGIN(0);}
 179 {NUMBER}/[ \n\r\t]          {s(NUMBER);c();BEGIN(0);}
 180 ^#[^\n]*\n                  {c();}
 181 [ \t\r]#[^\n]*\n            {c();}
 182 \"{STRING}\"                {s(STRING);c();BEGIN(0);}
 183 \"{STRING}$                 {c();printf("unterminated string in line %d: %s\n", line, yytext);exit(1);yyterminate();}
 184 {NAME}{S}*\+=               {s(ASSIGNMENT);prefix="<plus>";c();BEGIN(R);}
 185 {NAME}{S}*-=                {s(ASSIGNMENT);prefix="<minus>";c();BEGIN(R);}
 186 {NAME}{S}*=                 {s(ASSIGNMENT);c();BEGIN(R);}
 187 <R>{ /* values which appear only on the right-hand side of assignments, like: x=50% */
 188     [^ \n\t\r]*             {s(IDENTIFIER);c();BEGIN(0);}
 189 }
 190 \.include{S}.*\n                    {handleInclude(yytext, yyleng);}
 191 \.{NAME}                    {s(COMMAND);c();}
 192 {NAME}{S}*:                 {s(LABEL);c();}
 193 {NAME}                      {s(IDENTIFIER);c();}
 194 "["                         {c();BEGIN(BINARY);}
 195 {S}                         {c();}
 196 .                           {char c,c1=yytext[0];
 197                              printf("Syntax error in line %d, %d: %s", line, column, yytext);
 198                              while(1) {
 199                                  c=input();
 200                                  if(c=='\n' || c==EOF)
 201                                      break;
 202                                 printf("%c", c);
 203                              }
 204                              if(c1>='0' && c1<='9')
 205                                  printf(" (identifiers must not start with a digit)");
 206                              printf("\n");
 207                              exit(1);
 208                              yyterminate();
 209                             }
 210 <<EOF>>                     {c();
 211                              if ( --include_stack_ptr < 0 ) {
 212                                 s(END);
 213                                 yyterminate();
 214                              } else {
 215                                  yy_delete_buffer( YY_CURRENT_BUFFER );
 216                                  yy_switch_to_buffer(
 217                                       include_stack[include_stack_ptr] );
 218                                  column = column_stack[include_stack_ptr];
 219                                  line = line_stack[include_stack_ptr];
 220                              }
 221                             }
 222
 223 %%
 224
 225 int yywrap()
 226 {
 227     return 1;
 228 }
 229
 230 void freeTokens(struct token_t*file)
 231 {
 232     mem_clear(&strings);
 233     mem_clear(&tokens);
 234 }
 235
 236 struct token_t* generateTokens(char*filename)
 237 {
 238     FILE*fi = fopen(filename, "rb");
 239     int t;
 240     struct token_t*result;
 241     int num;
 242     if(!fi) {
 243         printf("Couldn't find file %s\n", filename);
 244         return 0;
 245     }
 246     yyin = fi;
 247
 248     mem_init(&strings);
 249     mem_init(&tokens);
 250     mem_put(&strings, &t, 1); //hack- make all valid strings start at position >0
 251
 252     line=1;
 253     column=1;
 254
 255     yylex();
 256     yy_delete_buffer(yy_current_buffer);
 257
 258     result = (struct token_t*)tokens.buffer;
 259     num = tokens.pos/sizeof(struct token_t);
 260
 261     for(t=0;t<tokens.pos/sizeof(struct token_t);t++) {
 262         if(result[t].text)
 263             result[t].text += (int)strings.buffer;
 264     }
 265
 266     fclose(fi);
 267     return result;
 268 }
 269