Added %top block syntax.

Added test for %top block.
Documented %top block.

1 files changed, 35 insertions, 4 deletions

diff --git a/buf.c b/buf.c
index 833837e..647be69 100644
--- a/buf.c
+++ b/buf.c
@@ -33,11 +33,24 @@
 
 #include "flexdef.h"
 
+/* Take note: The buffer object is sometimes used as a String buffer (one
+ * continuous string), and sometimes used as a list of strings, usually line by
+ * line.
+ * 
+ * The type is specified in buf_init by the elt_size. If the elt_size is
+ * sizeof(char), then the buffer should be treated as string buffer. If the
+ * elt_size is sizeof(char*), then the buffer should be treated as a list of
+ * strings.
+ *
+ * Certain functions are only appropriate for one type or the other. 
+ */
+
 /* global buffers. */
-struct Buf userdef_buf;		/* for user #definitions triggered by cmd-line. */
-struct Buf defs_buf;		/* for #define's autogenerated. List of strings. */
-struct Buf yydmap_buf;		/* string buffer to hold yydmap elements */
-struct Buf m4defs_buf;          /**< Holds m4 definitions. List of strings. */
+struct Buf userdef_buf;		/**< for user #definitions triggered by cmd-line. */
+struct Buf defs_buf;		/**< for #define's autogenerated. List of strings. */
+struct Buf yydmap_buf;		/**< string buffer to hold yydmap elements */
+struct Buf m4defs_buf;          /**< m4 definitions. List of strings. */
+struct Buf top_buf;             /**< contains %top code. String buffer. */
 
 struct Buf *buf_print_strings(struct Buf * buf, FILE* out)
 {
@@ -66,6 +79,24 @@ struct Buf *buf_prints (struct Buf *buf, const char *fmt, const char *s)
 	return buf;
 }
 
+/** Append a line directive to the string buffer.
+ * @param buf A string buffer.
+ * @param filename file name
+ * @param lineno line number
+ * @return buf
+ */
+struct Buf *buf_linedir (struct Buf *buf, const char* filename, int lineno)
+{
+    char   *t, *fmt = "#line %d \"%s\"\n";
+    
+    t = flex_alloc (strlen (fmt) + strlen (filename) + (int)(1 + log(lineno>=0?lineno:-lineno)/log(10)) + 1);
+    sprintf (t, fmt, lineno, filename);
+    buf = buf_strappend (buf, t);
+    flex_free (t);
+    return buf;
+}
+
+
 /** Append the contents of @a src to @a dest.
  * @param @a dest the destination buffer
  * @param @a dest the source buffer