src/parser.lex

   1 %{
   2
   3 #include <string.h>
   4 #include "q.h"
   5 #include "parser.h"
   6
   7 //RVALUE         {NUMBER}|{PERCENT}|{NAME}|\"{STRING}\"|{DIM}
   8 //<a>.                {printf("<a>%s\n", yytext);}
   9 // %x: exclusive, %s: inclusive
  10 char*type_names[] = {"twip","number","command","string","assignment","identifier","label","end"};
  11 static int line=1;
  12 static int column=1;
  13
  14 mem_t strings;
  15 mem_t tokens;
  16
  17 static void count(char*text, int len, int condition)
  18 {
  19     int t;
  20     for(t=0;t<len;t++) {
  21         if(text[t]=='\n') {
  22             line++;
  23             column=1;
  24         } else {
  25             column++;
  26         }
  27     }
  28 }
  29
  30 static char*prefix = 0;
  31
  32 static void store(enum type_t type, int line, int column, char*text, int length)
  33 {
  34     struct token_t token;
  35     string_t tmp;
  36     token.type = type;
  37     token.line = line;
  38     token.column = column;
  39     //printf("->%d(%s) %s\n", type, type_names[type], text);fflush(stdout);
  40
  41     token.text = 0;
  42     switch(type) {
  43         case END:
  44             string_set2(&tmp, "", 0);
  45             token.text = (char*)mem_putstring(&strings, tmp);
  46         break;
  47         case STRING:
  48             string_set2(&tmp, text+1, length-2);
  49             token.text = (char*)mem_putstring(&strings, tmp);
  50         break;
  51         case TWIP:
  52         case NUMBER:
  53         case IDENTIFIER:
  54             string_set2(&tmp, text, length);
  55             if(prefix) {
  56                 //strcat
  57                 token.text = (char*)mem_put(&strings, prefix, strlen(prefix));
  58                 mem_putstring(&strings, tmp);
  59             } else {
  60                 token.text = (char*)mem_putstring(&strings, tmp);
  61             }
  62             prefix = 0;
  63         break;
  64         case LABEL:
  65             string_set2(&tmp, text, length-1);
  66             token.text = (char*)mem_putstring(&strings, tmp);
  67         break;
  68         case COMMAND:
  69             string_set2(&tmp, text+1, length-1);
  70             token.text = (char*)mem_putstring(&strings, tmp);
  71         break;
  72         case ASSIGNMENT: {
  73             char*x = &text[length-1];
  74             if(x[-1] == '-' || x[-1] == '+')
  75                 x--;
  76             do{x--;} while(*x==32 || *x==10 || *x==13 || *x=='\t');
  77             x++; //first space
  78             string_set2(&tmp, text, x-text);
  79             token.text = (char*)mem_putstring(&strings, tmp);
  80             /*char*y,*x = strchr(text, '=');
  81             if(!x) exit(1);
  82             y=x;
  83             do{y--;} while(*y==32 || *y==10 || *y==13 || *y=='\t');
  84             do{x++;} while(*x==32 || *x==10 || *x==13 || *x=='\t');
  85             token.text1 = (char*)put(&strings, text, y-text + 1, 1);
  86             token.text2 = (char*)put(&strings, x, length-(x-text), 1);*/
  87         } break;
  88     }
  89
  90     mem_put(&tokens, &token, sizeof(struct token_t));
  91     prefix = 0;
  92 }
  93
  94 #define c() {count(yytext, yyleng, YY_START);}
  95 #define s(type) {store(type, line, column, yytext, yyleng);}
  96 %}
  97
  98 %s R
  99 %x BINARY
 100
 101 NAME     [a-zA-Z_./](-*[a-zA-Z0-9_./])*
 102 TWIP     ([0-9]+(\.([0-9]([05])?)?)?)
 103 NUMBER   [0-9]+(\.[0-9]*)?
 104 PERCENT  {NUMBER}%
 105 STRING   (\\.|[^\\"\n])*
 106 S        [ \n\r\t]
 107 RVALUE   \"{STRING}\"|([^ \n\r\t]+)
 108
 109 %%
 110
 111 <BINARY>\] {c();BEGIN(0);}
 112 <BINARY>.  {c();}
 113 <BINARY>\n {c();}
 114 {TWIP}/[ \n\r\t]            {s(TWIP);c();BEGIN(0);}
 115 {NUMBER}/[ \n\r\t]          {s(NUMBER);c();BEGIN(0);}
 116 ^#[^\n]*\n                  {c();}
 117 [ \t\r]#[^\n]*\n            {c();}
 118 \"{STRING}\"                {s(STRING);c();BEGIN(0);}
 119 \"{STRING}$                 {c();printf("unterminated string in line %d: %s\n", line, yytext);exit(1);yyterminate();}
 120 {NAME}{S}*\+=               {s(ASSIGNMENT);prefix="<plus>";c();BEGIN(R);}
 121 {NAME}{S}*-=                {s(ASSIGNMENT);prefix="<minus>";c();BEGIN(R);}
 122 {NAME}{S}*=                 {s(ASSIGNMENT);c();BEGIN(R);}
 123 <R>{ /* values which appear only on the right-hand side of assignments, like: x=50% */
 124     [^ \n\t\r]*             {s(IDENTIFIER);c();BEGIN(0);}
 125 }
 126 \.{NAME}                    {s(COMMAND);c();}
 127 {NAME}{S}*:                 {s(LABEL);c();}
 128 {NAME}                      {s(IDENTIFIER);c();}
 129 "["                         {c();BEGIN(BINARY);}
 130 {S}                         {c();}
 131 .                           {char c,c1=0;
 132                              printf("Syntax error in line %d, %d: %s", line, column, yytext);
 133                              while(1) {
 134                                  c=input();
 135                                  if(!c1) c1=c;
 136                                  if(c=='\n' || c==EOF)
 137                                      break;
 138                                 printf("%c", c);
 139                              }
 140                              if(c1>='0' && c1<='9')
 141                                  printf(" (identifiers must not start with a digit)");
 142                              printf("\n");
 143                              exit(1);
 144                              yyterminate();
 145                             }
 146 <<EOF>>                     {c();s(END);yyterminate();}
 147 %%
 148
 149 int yywrap()
 150 {
 151     return 1;
 152 }
 153
 154 void freeTokens(struct token_t*file)
 155 {
 156     mem_clear(&strings);
 157     mem_clear(&tokens);
 158 }
 159
 160 struct token_t* generateTokens(char*filename)
 161 {
 162     FILE*fi = fopen(filename, "rb");
 163     int t;
 164     struct token_t*result;
 165     int num;
 166     if(!fi) {
 167         printf("Couldn't find file %s\n", filename);
 168         return 0;
 169     }
 170     yyin = fi;
 171
 172     mem_init(&strings);
 173     mem_init(&tokens);
 174     mem_put(&strings, &t, 1); //hack- make all valid strings start at position >0
 175
 176     line=1;
 177     column=1;
 178
 179     yylex();
 180     yy_delete_buffer(yy_current_buffer);
 181
 182     result = (struct token_t*)tokens.buffer;
 183     num = tokens.pos/sizeof(struct token_t);
 184
 185     for(t=0;t<tokens.pos/sizeof(struct token_t);t++) {
 186         if(result[t].text)
 187             result[t].text += (int)strings.buffer;
 188     }
 189
 190     fclose(fi);
 191     return result;
 192 }
 193