initial

1 files changed, 105 insertions, 0 deletions

diff --git a/other/gramble/input-driver.c b/other/gramble/input-driver.c
new file mode 100644
index 0000000..e68bdf3
--- /dev/null
+++ b/other/gramble/input-driver.c
@@ -0,0 +1,105 @@
+/* gramble - grammar ramble
+ *
+ * team teso
+ *
+ * main grammar parser driver functions
+ */
+
+#include <setjmp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "input.h"
+
+
+extern int yydebug;
+extern FILE * yyout;
+extern int yyparse (void);
+
+
+void *  in_grammar = NULL;      /* parser return */
+
+char *  in_input_ptr;
+int     in_input_lim;
+
+jmp_buf in_yy_error_jmp;        /* to catch errors in parser */
+
+
+/* overridden yacc functions
+ */
+
+int
+yyerror (char *str)
+{
+        longjmp (in_yy_error_jmp, 1);
+
+        exit (EXIT_FAILURE);
+}
+
+
+int
+yywrap (void)
+{
+        return (1);
+}
+
+
+/*** driver interface
+ */
+
+/* in_parse
+ *
+ * parse a grammar from buffer pointed to by 'buf', which is 'buf_len' bytes
+ * long.
+ *
+ * return NULL on failure
+ * return pointer to grammar on success
+ */
+
+void *  /* FIXME: real pointer */
+in_parse (char *buf, int buf_len)
+{
+        in_grammar = NULL;
+
+
+        in_input_ptr = buf;
+        in_input_lim = buf_len;
+
+        if (setjmp (in_yy_error_jmp) != 0) {
+                if (in_grammar != NULL)
+                        return (NULL);
+
+                /* FIXME: free all associated memory */
+                /* freebla (in_grammar) */
+                return (NULL);
+        }
+
+        yyparse ();
+
+        return (in_grammar);
+}
+
+
+/* in_yyinput
+ *
+ * override yyinput functionality to allow more flexible parsing. internally
+ * used, never called by outsiders.
+ *
+ * return number of bytes read
+ */
+
+int
+in_yyinput (char *buf, int size_max)
+{       
+        int     n = 0;
+
+        n = (size_max >= in_input_lim) ? in_input_lim : size_max;
+        if (n > 0) {
+                memmove (buf, in_input_ptr, n);
+                in_input_ptr += n;
+                in_input_lim -= n;
+        }
+
+        return (n);
+}
+