Adapt `info probes' to support printing probes of different types.

A "probe type" (backend for the probe abstraction implemented in
probe.[ch]) can extend the information printed by `info probes' by
defining additional columns.  This means that when `info probes' is
used to print all the probes regardless of their types, some of the
columns will be "not applicable" to some of the probes (like, say, the
Semaphore column only makes sense for SystemTap probes).  This patch
makes `info probes' fill these slots with "n/a" marks (currently it
breaks the table) and not include headers for which no actual probe
has been found in the list of defined probes.

This patch also adds support for a new generic column "Type", that
displays the type of each probe.  SystemTap probes identify themselves
as "stap" probes.

gdb/ChangeLog:

2015-02-17  Jose E. Marchesi  <jose.marchesi@oracle.com>

	* probe.c (print_ui_out_not_applicables): New function.
	(exists_probe_with_pops): Likewise.
	(info_probes_for_ops): Do not include column headers for probe
	types for which no probe has been actually found on any object.
	Also invoke `print_ui_out_not_applicables' in order to match the
	column rows with the header when probes of several types are
	listed.
	Print the "Type" column.
	* probe.h (probe_ops): Added a new probe operation `type_name'.
	* stap-probe.c (stap_probe_ops): Add `stap_type_name'.
	(stap_type_name): New function.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index bf98df151dfa590611a3f7c9ea8ddb73c85a8a35..f988d9741da75be793e704a4d07572f452216c47 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,17 @@
+2015-02-17  Jose E. Marchesi  <jose.marchesi@oracle.com>
+
+       * probe.c (print_ui_out_not_applicables): New function.
+       (exists_probe_with_pops): Likewise.
+       (info_probes_for_ops): Do not include column headers for probe
+       types for which no probe has been actually found on any object.
+       Also invoke `print_ui_out_not_applicables' in order to match the
+       column rows with the header when probes of several types are
+       listed.
+       Print the "Type" column.
+       * probe.h (probe_ops): Added a new probe operation `type_name'.
+       * stap-probe.c (stap_probe_ops): Add `stap_type_name'.
+       (stap_type_name): New function.
+
 2015-02-17  Patrick Palka  <patrick@parcs.ath.cx>
 
        * tui/tui-io.c (tui_getc): Don't call key_is_command_char.

diff --git a/gdb/probe.c b/gdb/probe.c
index 56b5fc113876bae7573cec1182e054490299afb3..5ab2593bf914eaf9e67d00a46439155e1d0ef1ba 100644 (file)
--- a/gdb/probe.c
+++ b/gdb/probe.c
@@ -410,6 +410,31 @@ gen_ui_out_table_header_info (VEC (bound_probe_s) *probes,
   do_cleanups (c);
 }
 
+/* Helper function to print not-applicable strings for all the extra
+   columns defined in a probe_ops.  */
+
+static void
+print_ui_out_not_applicables (const struct probe_ops *pops)
+{
+  struct cleanup *c;
+  VEC (info_probe_column_s) *headings = NULL;
+  info_probe_column_s *column;
+  int ix;
+
+  if (pops->gen_info_probes_table_header == NULL)
+    return;
+
+  c = make_cleanup (VEC_cleanup (info_probe_column_s), &headings);
+  pops->gen_info_probes_table_header (&headings);
+
+  for (ix = 0;
+       VEC_iterate (info_probe_column_s, headings, ix, column);
+       ++ix)
+    ui_out_field_string (current_uiout, column->field_name, _("n/a"));
+
+  do_cleanups (c);
+}
+
 /* Helper function to print extra information about a probe and an objfile
    represented by PROBE.  */
 
@@ -482,6 +507,23 @@ get_number_extra_fields (const struct probe_ops *pops)
   return n;
 }
 
+/* Helper function that returns 1 if there is a probe in PROBES
+   featuring the given POPS.  It returns 0 otherwise.  */
+
+static int
+exists_probe_with_pops (VEC (bound_probe_s) *probes,
+                       const struct probe_ops *pops)
+{
+  struct bound_probe *probe;
+  int ix;
+
+  for (ix = 0; VEC_iterate (bound_probe_s, probes, ix, probe); ++ix)
+    if (probe->probe->pops == pops)
+      return 1;
+
+  return 0;
+}
+
 /* See comment in probe.h.  */
 
 void
@@ -497,6 +539,7 @@ info_probes_for_ops (const char *arg, int from_tty,
   size_t size_name = strlen ("Name");
   size_t size_objname = strlen ("Object");
   size_t size_provider = strlen ("Provider");
+  size_t size_type = strlen ("Type");
   struct bound_probe *probe;
   struct gdbarch *gdbarch = get_current_arch ();
 
@@ -517,6 +560,9 @@ info_probes_for_ops (const char *arg, int from_tty,
        }
     }
 
+  probes = collect_probes (objname, provider, probe_name, pops);
+  make_cleanup (VEC_cleanup (probe_p), &probes);
+
   if (pops == NULL)
     {
       const struct probe_ops *po;
@@ -529,18 +575,18 @@ info_probes_for_ops (const char *arg, int from_tty,
 
         To do that, we iterate over all probe_ops, querying each one about
         its extra fields, and incrementing `ui_out_extra_fields' to reflect
-        that number.  */
+        that number.  But note that we ignore the probe_ops for which no probes
+        are defined with the given search criteria.  */
 
       for (ix = 0; VEC_iterate (probe_ops_cp, all_probe_ops, ix, po); ++ix)
-       ui_out_extra_fields += get_number_extra_fields (po);
+       if (exists_probe_with_pops (probes, po))
+         ui_out_extra_fields += get_number_extra_fields (po);
     }
   else
     ui_out_extra_fields = get_number_extra_fields (pops);
 
-  probes = collect_probes (objname, provider, probe_name, pops);
-  make_cleanup (VEC_cleanup (probe_p), &probes);
   make_cleanup_ui_out_table_begin_end (current_uiout,
-                                      4 + ui_out_extra_fields,
+                                      5 + ui_out_extra_fields,
                                       VEC_length (bound_probe_s, probes),
                                       "StaticProbes");
 
@@ -552,15 +598,19 @@ info_probes_for_ops (const char *arg, int from_tty,
   /* What's the size of an address in our architecture?  */
   size_addr = gdbarch_addr_bit (gdbarch) == 64 ? 18 : 10;
 
-  /* Determining the maximum size of each field (`provider', `name' and
-     `objname').  */
+  /* Determining the maximum size of each field (`type', `provider',
+     `name' and `objname').  */
   for (i = 0; VEC_iterate (bound_probe_s, probes, i, probe); ++i)
     {
+      const char *probe_type = probe->probe->pops->type_name (probe->probe);
+
+      size_type = max (strlen (probe_type), size_type);
       size_name = max (strlen (probe->probe->name), size_name);
       size_provider = max (strlen (probe->probe->provider), size_provider);
       size_objname = max (strlen (objfile_name (probe->objfile)), size_objname);
     }
 
+  ui_out_table_header (current_uiout, size_type, ui_left, "type", _("Type"));
   ui_out_table_header (current_uiout, size_provider, ui_left, "provider",
                       _("Provider"));
   ui_out_table_header (current_uiout, size_name, ui_left, "name", _("Name"));
@@ -571,10 +621,12 @@ info_probes_for_ops (const char *arg, int from_tty,
       const struct probe_ops *po;
       int ix;
 
-      /* We have to generate the table header for each new probe type that we
-        will print.  */
+      /* We have to generate the table header for each new probe type
+        that we will print.  Note that this excludes probe types not
+        having any defined probe with the search criteria.  */
       for (ix = 0; VEC_iterate (probe_ops_cp, all_probe_ops, ix, po); ++ix)
-       gen_ui_out_table_header_info (probes, po);
+       if (exists_probe_with_pops (probes, po))
+         gen_ui_out_table_header_info (probes, po);
     }
   else
     gen_ui_out_table_header_info (probes, pops);
@@ -586,9 +638,11 @@ info_probes_for_ops (const char *arg, int from_tty,
   for (i = 0; VEC_iterate (bound_probe_s, probes, i, probe); ++i)
     {
       struct cleanup *inner;
+      const char *probe_type = probe->probe->pops->type_name (probe->probe);
 
       inner = make_cleanup_ui_out_tuple_begin_end (current_uiout, "probe");
 
+      ui_out_field_string (current_uiout, "type",probe_type);
       ui_out_field_string (current_uiout, "provider", probe->probe->provider);
       ui_out_field_string (current_uiout, "name", probe->probe->name);
       ui_out_field_core_addr (current_uiout, "addr",
@@ -604,6 +658,8 @@ info_probes_for_ops (const char *arg, int from_tty,
               ++ix)
            if (probe->probe->pops == po)
              print_ui_out_info (probe->probe);
+           else if (exists_probe_with_pops (probes, po))
+             print_ui_out_not_applicables (po);
        }
       else
        print_ui_out_info (probe->probe);

diff --git a/gdb/probe.h b/gdb/probe.h
index 1dd582d84f3b1d428c0e184a2fe29bf2cfc52109..5df1976af57ae7cba8fa880e7b149b20a397f8d2 100644 (file)
--- a/gdb/probe.h
+++ b/gdb/probe.h
@@ -113,6 +113,12 @@ struct probe_ops
 
     void (*destroy) (struct probe *probe);
 
+    /* Return a pointer to a name identifying the probe type.  This is
+       the string that will be displayed in the "Type" column of the
+       `info probes' command.  */
+
+    const char *(*type_name) (struct probe *probe);
+
     /* Function responsible for providing the extra fields that will be
        printed in the `info probes' command.  It should fill HEADS
        with whatever extra fields it needs.  If the backend doesn't need

diff --git a/gdb/stap-probe.c b/gdb/stap-probe.c
index ffe4dd16be9a1f689849ac1845f10f0ff37422c4..50ad533516e7f09e9aacb06005bca9eaa719c8bd 100644 (file)
--- a/gdb/stap-probe.c
+++ b/gdb/stap-probe.c
@@ -1703,6 +1703,15 @@ stap_get_probes (VEC (probe_p) **probesp, struct objfile *objfile)
     }
 }
 
+/* Implementation of the type_name method.  */
+
+static const char *
+stap_type_name (struct probe *probe)
+{
+  gdb_assert (probe->pops == &stap_probe_ops);
+  return "stap";
+}
+
 static int
 stap_probe_is_linespec (const char **linespecp)
 {
@@ -1754,6 +1763,7 @@ const struct probe_ops stap_probe_ops =
   stap_set_semaphore,
   stap_clear_semaphore,
   stap_probe_destroy,
+  stap_type_name,
   stap_gen_info_probes_table_header,
   stap_gen_info_probes_table_values,
 };