src/lexer.rl

   1 #include <stdio.h>
   2 #include <stdint.h>
   3 #include <stdlib.h>
   4 #include <errno.h>
   5 #include <unistr.h>
   6 #include "parser.tab.h"
   7 #include "apc.h"
   8 #include "print.h"
   9 /* Public */
  10 int  lexer_init(void);
  11 void lexer_quit(void);
  12 int  lexer_lexfile(uint8_t*);
  13 int  lexer_lexdir(uint8_t*);
  14 int  lexer_lexstring(uint8_t*, int);
  15 //apc.c
  16 static
  17 yypstate* pstate;
  18 static
  19 yycstate* cstate;
  20 /* Ring buffer for keeping lexical tokens valid for up to 255 tokens */
  21 static
  22 YYSTYPE   lval_stack[0xFF + 1];
  23 static
  24 uint8_t   lval_offs;
  25 #define $($)#$
  26 #define PUSHTOK(T,L) yypush_parse(pstate, T, (L), cstate)
  27 #define LEXTOK(T,Y,L) do {                                      \
  28     if (DEBUG) {                                                \
  29       ulc_fprintf(stdout, "["$(T));                             \
  30       switch (T) {                                              \
  31       case NAME: case PATH:                                     \
  32         ulc_fprintf(stdout, "->%U", L); break;                  \
  33       case REF:                                                 \
  34         ulc_fprintf(stdout, "->%X", L); break;                  \
  35       default: break;                                           \
  36       }                                                         \
  37       ulc_fprintf(stdout, "]");                                 \
  38     }                                                           \
  39     lval_stack[lval_offs].Y = L;                                \
  40     PUSHTOK(T,lval_stack + lval_offs);                          \
  41     lval_offs++;                                                \
  42     ntok++;                                                     \
  43   } while (0)
  44 #define PUSHFACE(F) LEXTOK(FACING, face, F)
  45 #define PUSHREF(R)  LEXTOK(REF, ref, R)
  46 #define PUSHLINK()  LEXTOK(LINK, val, 0)
  47 #define PUSHNUM(N)  LEXTOK(NUM, val, N)
  48 #define PUSHNAME(N) LEXTOK(NAME, str, N)
  49 #define PUSHOP(O)   LEXTOK(O, val, 0)
  50 #define PUSHPATH(P) LEXTOK(PATH, str, P)
  51
  52 /* Lexstring is the main lexer for APC and is generated by ragel. It lexes file names of files
  53    that have been scanned and pushes their types and values into the tok_stack, which yyparse
  54    eventually calls during parsing. */
  55
  56 %%{
  57   machine lexstring;
  58
  59   # set up yylval and tok_t to be pushed to stack
  60   action push_ref       { errno = 0;
  61                           lval.ref = strtoll((char*)ts,NULL,16);
  62                           if (errno)
  63                             { ulc_fprintf(stderr, "Invalid hex number in file %U\n",str);
  64                               exit(1);
  65                             }
  66                           PUSHREF(lval.ref);
  67                         }
  68   action push_link      { PUSHLINK(); }
  69   action push_val       { errno = 0;
  70                           lval.val = strtoll((char*)ts,NULL,10);
  71                           if (errno)
  72                             { ulc_fprintf(stderr, "strtoll could not parse %U\n",str);
  73                               exit(1);
  74                             }
  75                           PUSHNUM(lval.val);
  76                         }
  77   action push_name      { PUSHNAME(ts); }
  78   action push_map       { PUSHOP(MAP);  }
  79   action set_ts         { ts = p;       }
  80   action push_SS        { PUSHOP(SS);   }
  81   action push_S         { PUSHFACE(SFACE); }
  82   action push_SW        { PUSHFACE(SWFACE); }
  83   action push_W         { PUSHFACE(WFACE); }
  84   action push_NW        { PUSHFACE(NWFACE); }
  85   action push_N         { PUSHFACE(NFACE); }
  86   action push_NE        { PUSHFACE(NEFACE); }
  87   action push_E         { PUSHFACE(EFACE); }
  88   action push_SE        { PUSHFACE(SEFACE); }
  89   action ref_error      { ulc_fprintf(stderr, "ref from %U to %U has an inappropriate amount of hex digits, it must have eight.\n", ts, p);
  90                           exit(1);
  91                         }
  92   action p              { dprintf("Lexer_lexstring:: p = %U\n", p); }
  93
  94   N = 'N' %push_N;
  95   W = 'W' %push_W;
  96   S = 'S' %push_S;
  97   E = 'E' %push_E;
  98   NW = 'NW' %push_NW;
  99   NE = 'NE' %push_NW;
 100   SW = 'SW' %push_SW;
 101   SE = 'SE' %push_SE;
 102
 103   tok_delimiter = [_\0];
 104
 105   direction = (N | W | S | E | NW | NE | SW | SE) ;
 106   dimensions = (digit+ - '0') >set_ts %push_val 'x' (digit+ - '0') >set_ts  %push_val;
 107   link = '#'  %push_link;
 108   SS = ('+SS' %to(push_SS)) | ('+SS' %to(push_SS) link ) ;
 109   ref = '0x' >set_ts alnum{8} $err(ref_error) %push_ref ;
 110   val = digit+ >set_ts %push_val ;
 111   name = lower >set_ts (lower | digit)*  %push_name ;
 112   map = '+MAP' %to(push_map);
 113   tok = (name | val | ref | dimensions | map | link | SS | direction);
 114
 115
 116   main := (tok tok_delimiter)* tok [\0];
 117
 118   write data nofinal noerror noprefix;
 119
 120 }%%
 121
 122 int lexer_init
 123 ( void )
 124 { pstate = yypstate_new();
 125   cstate = yycstate_new();
 126   lval_offs = 0;
 127   return !pstate || !cstate;
 128   return en_main == 1;
 129 }
 130
 131 void lexer_quit
 132 ( void )
 133 { if (pstate) yypstate_delete(pstate);
 134   if (cstate) yycstate_delete(cstate);
 135 }
 136
 137 int lexer_lexstring
 138 ( uint8_t* str,
 139   int size
 140 )
 141 { uint8_t* p, * ts, * pe, * eof;
 142   int cs, ntok;
 143   YYSTYPE lval;
 144
 145   ntok = 0;
 146   p = ts = str;
 147   pe = eof =  p + size + 1;
 148
 149   dprintf("\n|---Begin lexstring on p = %U, pe = %p.---|\n",p, pe);
 150
 151   %%write init;
 152   %%write exec;
 153
 154   dprintf("\n|---Ending lexstring of file %U, pushed %d tokens.---|\n",str, ntok);
 155
 156   return ntok;
 157 }
 158
 159 /* Lexical analysis of a file
 160    Strips a filename to its base name, then sends it to lexer_lexstring before
 161    pushing a PATH token with the filename
 162    Returns the number of tokens pushed to the parser.
 163 */
 164 int lexer_lexfile
 165 ( uint8_t* filename )
 166 { uint8_t* last_period,* iter,* filename_end;
 167   int      ntok;
 168   last_period = NULL;
 169   for (iter = filename; *iter; iter++)
 170     switch (*iter)
 171       { // Keep track of the last 'dot' in the name
 172         case '.' : last_period = iter; continue;
 173         // replace '_' with '\0' so bison can use strlen on them as tokens.
 174         case '_' : *iter = '\0';
 175         default: continue;
 176       }
 177   // Mark the end of the filename
 178   filename_end = iter;
 179   // Lex from either the last period, if present, or filename end
 180   ntok = (last_period) ?
 181     lexer_lexstring(filename, (int)(last_period - filename))
 182   : lexer_lexstring(filename, (int)(iter - filename));
 183   // Replace nulls with their original '_'
 184   for (iter = filename; iter < filename_end; iter++)
 185     if (*iter == '\0')
 186       *iter = '_';
 187   PUSHPATH(filename);
 188   return ntok + 1;
 189 }
 190
 191 int lexer_lexdir
 192 ( uint8_t* dirname )
 193 { int ntok;
 194   ntok = 0;
 195   PUSHNAME(dirname);
 196   PUSHOP(CLOPEN);
 197   return ntok;
 198 }
 199
 200 int lexer_closedir
 201 ( void )
 202 { int ntok = 0;
 203   PUSHOP(CLCLOSE);
 204   return ntok;
 205 }