+/* Lexer
+ If the token buffer is empty, 'lexer' will initialize the token buffer and
+ call 'lexer_scandir'. If SCAN_ERROR is returned, an error is printed
+ before sending a null return to bison. If 0 tokens are generated, the error
+ printing is skipped. In all other cases, 'yylval' is set, and the token's
+ integer representation is returned.
+*/
+int lexer
+#define $($)#$
+#define SCAN_ERROR -1
+#define TK_EMPTY (TK_STACKP == TK_STACKX)
+#define FAIL(...) \
+ do { \
+ fprintf(stderr,__VA_ARGS__); \
+ goto done; \
+ } while (0)
+()
+{ struct tok token;
+ start:
+ while (DE_LEN() > 0) //lex any directory entries in our stack
+ if (lexer_lexfile(DE_POP()->d_name) == 0)
+ FAIL("Lexer failed to tokenize [%s]\n",(*DE_STACKB)->d_name);
+ if (TK_EMPTY) //if there are no tokens,
+ { TK_INIT(); //initialize the token stack back to 0
+ switch (scanner())
+ { case SCAN_ERROR: //if an error occurred,
+ FAIL("Scanner error\n");
+ case 0: //if the the scanner finds no dirents,
+ goto done; //then we are done
+ default: //if we found some elements to scan,
+ goto start; //start over and lex them
+ }
+ }
+ token = TK_POP();
+ yylval = token.lval;
+ return token.tok_t;
+ done:
+ yylval.val = 0;