DISABLE_STDIO/ENABLE_DEBUG macros to rename; close #3014

changes:
 * rename DISABLE_STDIO -> MRB_DISABLE_STDIO
 * rename ENABLE_DEBUG -> MRB_ENABLE_DEBUG_HOOK
 * no more opposite macro definitions (e.g. ENABLE_STDIO, DISABLE_DEBUG).
 * rewrite above macro references throughout the code.
 * update documents

7 files changed, 19 insertions, 30 deletions

diff --git a/src/backtrace.c b/src/backtrace.c
index a672a6c95..cbf89e09d 100644
--- a/src/backtrace.c
+++ b/src/backtrace.c
@@ -25,7 +25,7 @@ struct backtrace_location {
 
 typedef void (*output_stream_func)(mrb_state*, struct backtrace_location*, void*);
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 
 struct print_backtrace_args {
   FILE *stream;
@@ -165,7 +165,7 @@ exc_output_backtrace(mrb_state *mrb, struct RObject *exc, output_stream_func fun
    overwritten.  So invoke these functions just after detecting exceptions.
 */
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 
 MRB_API void
 mrb_print_backtrace(mrb_state *mrb)
diff --git a/src/codedump.c b/src/codedump.c
index d87c729f9..6db5c6596 100644
--- a/src/codedump.c
+++ b/src/codedump.c
@@ -5,7 +5,7 @@
 #include "mruby/string.h"
 #include "mruby/proc.h"
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 static int
 print_r(mrb_state *mrb, mrb_irep *irep, size_t n, int pre)
 {
@@ -53,7 +53,7 @@ print_lv(mrb_state *mrb, mrb_irep *irep, mrb_code c, int r)
 static void
 codedump(mrb_state *mrb, mrb_irep *irep)
 {
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
   int i;
   int ai;
   mrb_code c;
diff --git a/src/dump.c b/src/dump.c
index 734f38043..6a70eacaa 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -989,7 +989,7 @@ mrb_dump_irep(mrb_state *mrb, mrb_irep *irep, uint8_t flags, uint8_t **bin, size
   return dump_irep(mrb, irep, dump_flags(flags, FLAG_BYTEORDER_NONATIVE), bin, bin_size);
 }
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 
 int
 mrb_dump_irep_binary(mrb_state *mrb, mrb_irep *irep, uint8_t flags, FILE* fp)
@@ -1092,4 +1092,4 @@ mrb_dump_irep_cfunc(mrb_state *mrb, mrb_irep *irep, uint8_t flags, FILE *fp, con
   return result;
 }
 
-#endif /* ENABLE_STDIO */
+#endif /* MRB_DISABLE_STDIO */
diff --git a/src/error.c b/src/error.c
index 66e552557..e2bcebb60 100644
--- a/src/error.c
+++ b/src/error.c
@@ -309,7 +309,7 @@ mrb_name_error(mrb_state *mrb, mrb_sym id, const char *fmt, ...)
 MRB_API void
 mrb_warn(mrb_state *mrb, const char *fmt, ...)
 {
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
   va_list ap;
   mrb_value str;
 
@@ -324,7 +324,7 @@ mrb_warn(mrb_state *mrb, const char *fmt, ...)
 MRB_API mrb_noreturn void
 mrb_bug(mrb_state *mrb, const char *fmt, ...)
 {
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
   va_list ap;
   mrb_value str;
 
diff --git a/src/load.c b/src/load.c
index 36fae9aee..aa8c501e5 100644
--- a/src/load.c
+++ b/src/load.c
@@ -642,7 +642,7 @@ mrb_load_irep(mrb_state *mrb, const uint8_t *bin)
   return mrb_load_irep_cxt(mrb, bin, NULL);
 }
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 
 MRB_API mrb_irep*
 mrb_read_irep_file(mrb_state *mrb, FILE* fp)
@@ -704,4 +704,4 @@ mrb_load_irep_file(mrb_state *mrb, FILE* fp)
 {
   return mrb_load_irep_file_cxt(mrb, fp, NULL);
 }
-#endif /* ENABLE_STDIO */
+#endif /* MRB_DISABLE_STDIO */
diff --git a/src/print.c b/src/print.c
index 077fa4f06..111145a34 100644
--- a/src/print.c
+++ b/src/print.c
@@ -8,7 +8,7 @@
 #include "mruby/string.h"
 #include "mruby/variable.h"
 
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 static void
 printstr(mrb_value obj, FILE *stream)
 {
@@ -24,35 +24,24 @@ printstr(mrb_value obj, FILE *stream)
 MRB_API void
 mrb_p(mrb_state *mrb, mrb_value obj)
 {
-  mrb_value val = mrb_inspect(mrb, obj);
-
-  printstr(val, stdout);
+  printstr(mrb_inspect(mrb, obj), stdout);
 }
 
 MRB_API void
 mrb_print_error(mrb_state *mrb)
 {
-  mrb_value s;
-
   mrb_print_backtrace(mrb);
-  s = mrb_funcall(mrb, mrb_obj_value(mrb->exc), "inspect", 0);
-  printstr(s, stderr);
+  printstr(mrb_funcall(mrb, mrb_obj_value(mrb->exc), "inspect", 0), stderr);
 }
 
 MRB_API void
 mrb_show_version(mrb_state *mrb)
 {
-  mrb_value msg;
-
-  msg = mrb_const_get(mrb, mrb_obj_value(mrb->object_class), mrb_intern_lit(mrb, "MRUBY_DESCRIPTION"));
-  printstr(msg, stdout);
+  printstr(mrb_const_get(mrb, mrb_obj_value(mrb->object_class), mrb_intern_lit(mrb, "MRUBY_DESCRIPTION")), stdout);
 }
 
 MRB_API void
 mrb_show_copyright(mrb_state *mrb)
 {
-  mrb_value msg;
-
-  msg = mrb_const_get(mrb, mrb_obj_value(mrb->object_class), mrb_intern_lit(mrb, "MRUBY_COPYRIGHT"));
-  printstr(msg, stdout);
+  printstr(mrb_const_get(mrb, mrb_obj_value(mrb->object_class), mrb_intern_lit(mrb, "MRUBY_COPYRIGHT")), stdout);
 }
diff --git a/src/vm.c b/src/vm.c
index 34aeddb94..174c04112 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -22,7 +22,7 @@
 #include "value_array.h"
 #include "mruby/throw.h"
 
-#ifndef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
 #if defined(__cplusplus)
 extern "C" {
 #endif
@@ -693,7 +693,7 @@ argnum_error(mrb_state *mrb, mrb_int num)
 
 #define ERR_PC_SET(mrb, pc) mrb->c->ci->err = pc;
 #define ERR_PC_CLR(mrb)     mrb->c->ci->err = 0;
-#ifdef ENABLE_DEBUG
+#ifdef MRB_ENABLE_DEBUG_HOOK
 #define CODE_FETCH_HOOK(mrb, irep, pc, regs) if ((mrb)->code_fetch_hook) (mrb)->code_fetch_hook((mrb), (irep), (pc), (regs));
 #else
 #define CODE_FETCH_HOOK(mrb, irep, pc, regs)
@@ -2340,10 +2340,10 @@ RETRY_TRY_BLOCK:
 
     CASE(OP_DEBUG) {
       /* A B C    debug print R(A),R(B),R(C) */
-#ifdef ENABLE_DEBUG
+#ifdef MRB_ENABLE_DEBUG_HOOK
       mrb->debug_op_hook(mrb, irep, pc, regs);
 #else
-#ifdef ENABLE_STDIO
+#ifndef MRB_DISABLE_STDIO
       printf("OP_DEBUG %d %d %d\n", GETARG_A(i), GETARG_B(i), GETARG_C(i));
 #else
       abort();