[PATCH v2 02/25] Make gdb_stdout&co be per UI

[Pedro Alves <palves@redhat.com>]

We need to have these send output to the proper UI.

However, this patch still make them look like globals.  Kind of like
__thread variables, if you will.  Changing everything throughout to
write something like current_ui->gdb_stdout instead would be massive
overkill, IMNSHO.

I left gdb_stdtargin/stdtarg/stdtargerr global, but maybe that was a
mistake -- IIRC, MI formats target i/o differently, so if we have a
separate MI channel, then I guess target output should go there
instead of to gdb's stdout.  OTOH, maybe GDB should send that instead
to "set inferior-tty", instead of multiplexing it over MI.  Likely
wouldn't work on all hosts though...
---
 gdb/main.c  |  4 ----
 gdb/top.c   | 15 +++++++++++++++
 gdb/top.h   | 17 +++++++++++++++++
 gdb/utils.h | 19 ++++++++++++++-----
 4 files changed, 46 insertions(+), 9 deletions(-)

diff --git a/gdb/main.c b/gdb/main.c
index 93ed98f..44d1a90 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -68,10 +68,6 @@ static int gdb_datadir_provided = 0;
    the possibly relocated path to python's lib directory.  */
 char *python_libdir = 0;
 
-struct ui_file *gdb_stdout;
-struct ui_file *gdb_stderr;
-struct ui_file *gdb_stdlog;
-struct ui_file *gdb_stdin;
 /* Target IO streams.  */
 struct ui_file *gdb_stdtargin;
 struct ui_file *gdb_stdtarg;
diff --git a/gdb/top.c b/gdb/top.c
index 913284a..ec10a34 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -85,6 +85,21 @@ extern void initialize_all_files (void);
 #define DEFAULT_PROMPT	"(gdb) "
 #endif
 
+/* Generate a function that exports a pointer to a field of the
+   current UI.  */
+
+#define gen_ret_current_ui_field_ptr(type, name)	\
+type *							\
+current_ui_## name ## _ptr (void)			\
+{							\
+  return &current_ui->m_ ## name;		\
+}
+
+gen_ret_current_ui_field_ptr (struct ui_file *, gdb_stdout)
+gen_ret_current_ui_field_ptr (struct ui_file *, gdb_stdin)
+gen_ret_current_ui_field_ptr (struct ui_file *, gdb_stderr)
+gen_ret_current_ui_field_ptr (struct ui_file *, gdb_stdlog)
+
 /* Initialization file name for gdb.  This is host-dependent.  */
 
 const char gdbinit[] = GDBINIT;
diff --git a/gdb/top.h b/gdb/top.h
index fc4e90a..d404427 100644
--- a/gdb/top.h
+++ b/gdb/top.h
@@ -49,6 +49,23 @@ struct ui
   /* The function to invoke when a complete line of input is ready for
      processing.  */
   void (*input_handler) (char *);
+
+  /* The fields below that start with "m_" are "private".  They're
+     meant to be accessed through wrapper macros that make them look
+     like globals.  */
+
+  /* The ui_file streams.  */
+  /* Normal results */
+  struct ui_file *m_gdb_stdout;
+  /* Input stream */
+  struct ui_file *m_gdb_stdin;
+  /* Serious error notifications */
+  struct ui_file *m_gdb_stderr;
+  /* Log/debug/trace messages that should bypass normal stdout/stderr
+     filtering.  For moment, always call this stream using
+     *_unfiltered.  In the very near future that restriction shall be
+     removed - either call shall be unfiltered.  (cagney 1999-06-13).  */
+  struct ui_file *m_gdb_stdlog;
 };
 
 extern struct ui *current_ui;
diff --git a/gdb/utils.h b/gdb/utils.h
index 0687c86..bf77d7d 100644
--- a/gdb/utils.h
+++ b/gdb/utils.h
@@ -156,18 +156,27 @@ extern void reinitialize_more_filter (void);
 
 extern int pagination_enabled;
 
-/* Global ui_file streams.  These are all defined in main.c.  */
+extern struct ui_file **current_ui_gdb_stdout_ptr (void);
+extern struct ui_file **current_ui_gdb_stdin_ptr (void);
+extern struct ui_file **current_ui_gdb_stderr_ptr (void);
+extern struct ui_file **current_ui_gdb_stdlog_ptr (void);
+
+/* The current top level's ui_file streams.  */
+
 /* Normal results */
-extern struct ui_file *gdb_stdout;
+#define gdb_stdout (*current_ui_gdb_stdout_ptr ())
 /* Input stream */
-extern struct ui_file *gdb_stdin;
+#define gdb_stdin (*current_ui_gdb_stdin_ptr ())
 /* Serious error notifications */
-extern struct ui_file *gdb_stderr;
+#define gdb_stderr (*current_ui_gdb_stderr_ptr ())
 /* Log/debug/trace messages that should bypass normal stdout/stderr
    filtering.  For moment, always call this stream using
    *_unfiltered.  In the very near future that restriction shall be
    removed - either call shall be unfiltered.  (cagney 1999-06-13).  */
-extern struct ui_file *gdb_stdlog;
+#define gdb_stdlog (*current_ui_gdb_stdlog_ptr ())
+
+/* Truly global ui_file streams.  These are all defined in main.c.  */
+
 /* Target output that should bypass normal stdout/stderr filtering.
    For moment, always call this stream using *_unfiltered.  In the
    very near future that restriction shall be removed - either call
-- 
2.5.0