Adding a debugger. This is an experimental prototype.

* Makefile (OBJS): New object file debug.o.

* dep.mk: Updated.

* match.c (h_fun): Use debug_begin and debug_end macros
to set up a debug frame for backtracing.
(match_line, match_files): Call debug_check to give debugger a chance
to instrument call.
(v_fun): Use debug_begin and debug_end macros to set up a debug frame
for backtracing. Call debug_check to give debugger a chance to
instrument call.

* stream.c (struct strm_ops): New function pointer, flush.
(stdio_maybe_write_error): Wrong word in error message corrected.
(stdio_flush): New static function.
(stdio_ops, pipe_ops): New function entered into tables.
(flush_stream): New function.

* stream.h (flush_stream): Declared.

* txr.c (help): New options documented.
(main): call to debug_init added. New debug options parsed and
opt_debugger set accordingly.

* unwind.c (uw_push_debug, uw_current_frame): New function.

* unwind.h (uw_frtype): New enumeration member UW_DBG.
(struct uw_debug): New frame variant.
(union uw_frame): New member, db.
(uw_push_debug, uw_current_frame): Declared,

* debug.c: New file.

* debug.h: New file.

1 files changed, 15 insertions, 1 deletions

diff --git a/match.c b/match.c
index a26f8191..0948ce37 100644
--- a/match.c
+++ b/match.c
@@ -43,6 +43,7 @@
 #include "utf8.h"
 #include "filter.h"
 #include "hash.h"
+#include "debug.h"
 #include "match.h"
 
 int output_produced;
@@ -928,9 +929,11 @@ static val h_fun(match_line_ctx c, match_line_ctx *cout)
     {
       uw_block_begin(nil, result);
       uw_env_begin;
+      debug_begin(sym, args, ub_p_a_pairs, c.bindings, c.dataline, c.data_lineno, c.pos);
 
       result = match_line(ml_bindings_specline(c, bindings_cp, body));
 
+      debug_end;
       uw_env_end;
       uw_block_end;
 
@@ -995,6 +998,8 @@ static val match_line(match_line_ctx c)
 
     elem = first(c.specline);
 
+    debug_check(elem, c.bindings, c.dataline, c.data_lineno, c.pos);
+
     switch (elem ? type(elem) : 0) {
     case CONS: /* directive */
       {
@@ -2844,6 +2849,8 @@ static val v_fun(match_files_ctx *c)
     val piter, aiter;
     val bindings_cp = copy_alist(c->bindings);
 
+    debug_check(specline, c->bindings, if2(consp(c->data), car(c->data)), c->data_lineno, nil);
+
     if (!equal(length(args), length(params)))
       sem_error(specline, lit("function ~a takes ~a argument(s)"),
                 sym, length(params), nao);
@@ -2873,7 +2880,10 @@ static val v_fun(match_files_ctx *c)
     {
       uw_block_begin(nil, result);
       uw_env_begin;
+      debug_begin(sym, args, ub_p_a_pairs, c->bindings, if2(consp(c->data), car(c->data)),
+                  c->data_lineno, nil);
       result = match_files(mf_spec_bindings(*c, body, bindings_cp));
+      debug_end;
       uw_env_end;
       uw_block_end;
 
@@ -2979,7 +2989,11 @@ repeat_spec_same_data:
 
       if (entry) {
         v_match_func vmf = (v_match_func) cptr_get(entry);
-        val result = vmf(&c);
+        val result;
+
+        debug_check(first_spec, c.bindings, if2(consp(c.data), car(c.data)), c.data_lineno, nil);
+
+        result = vmf(&c);
 
         if (result == next_spec_k) {
           if ((c.spec = rest(c.spec)) == nil)