[PATCH, doc RFA] Make second arg to "mt print *symbols" a regexp

[Doug Evans <dje at google dot com>]

Hi.

This patch was helpful while debugging a gdb crash from the gdb-generated
.gdb_index addrmap. It just changes the optional second arg of
"mt print {,p,m}symbols" to be a regexp of a filename instead of the
filename itself - the regexp is just easier to get right the first time.

Also, I noticed "mt print msymbols" was looping over pspaces.
The others don't, and for myself I would never want the current
behaviour. And if I ever did I'd rather have a composable command
that applied a specific command over all pspaces than building
this functionality into the command itself!

This patch also does a bit of misc cleanup.
E.g., DEV_TTY is supposed to be the default output file, but these commands
do not take a default output file.

2015-09-29  Doug Evans  <dje@google.com>

	* psymtab.c (DEV_TTY): Delete.
	(maintenance_print_psymbols): Rewrite argument processing.
	Treat optional second parameter as a regexp.
	* symmisc.c (DEV_TTY): Delete.
	(maintenance_print_symbols): Rewrite argument processing.
	Treat optional second parameter as a regexp.
	(maintenance_print_msymbols): Ditto.

	doc/
	* gdb.texinfo (Symbols): Update docs of mt print symbols, psymbols,
	and msymbols.

diff --git a/gdb/psymtab.c b/gdb/psymtab.c
index d565c67..1cce5c4 100644
--- a/gdb/psymtab.c
+++ b/gdb/psymtab.c
@@ -36,10 +36,6 @@
 #include "cp-support.h"
 #include "gdbcmd.h"

-#ifndef DEV_TTY
-#define DEV_TTY "/dev/tty"
-#endif
-
 struct psymbol_bcache
 {
   struct bcache *bcache;
@@ -1890,31 +1886,28 @@ maintenance_print_psymbols (char *args, int  
from_tty)
   char **argv;
   struct ui_file *outfile;
   struct cleanup *cleanups;
-  char *symname = NULL;
-  char *filename = DEV_TTY;
+  char *filename = NULL;
+  char *print_only = NULL;
   struct objfile *objfile;
   struct partial_symtab *ps;

   dont_repeat ();

-  if (args == NULL)
-    {
-      error (_("\
-print-psymbols takes an output file name and optional symbol file name"));
-    }
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
-
-  if (argv[0] != NULL)
+  /* Note: gdb_buildargv cannot currently return { NULL },
+     but we play it safe just in case that changes.  */
+  if (argv == NULL || argv[0] == NULL)
     {
-      filename = argv[0];
-      /* If a second arg is supplied, it is a source file name to match  
on.  */
-      if (argv[1] != NULL)
-	{
-	  symname = argv[1];
-	}
+      error (_("\"print psymbols\" takes an output file name"
+	       " and an optional symbol file name"));
     }

+  filename = argv[0];
+  /* If a second arg is supplied, it is a source file name to match on.  */
+  if (argv[1] != NULL)
+    print_only = argv[1];
+
   filename = tilde_expand (filename);
   make_cleanup (xfree, filename);

@@ -1923,10 +1916,13 @@ print-psymbols takes an output file name and  
optional symbol file name"));
     perror_with_name (filename);
   make_cleanup_ui_file_delete (outfile);

+  if (print_only != NULL)
+    re_comp (print_only);
+
   ALL_PSYMTABS (objfile, ps)
     {
       QUIT;
-      if (symname == NULL || filename_cmp (symname, ps->filename) == 0)
+      if (print_only == NULL || re_exec (ps->filename))
 	dump_psymtab (objfile, ps, outfile);
     }
   do_cleanups (cleanups);
diff --git a/gdb/symmisc.c b/gdb/symmisc.c
index 53d8c03..810b60c 100644
--- a/gdb/symmisc.c
+++ b/gdb/symmisc.c
@@ -37,13 +37,8 @@
 #include "gdbcmd.h"
 #include "source.h"
 #include "readline/readline.h"
-
 #include "psymtab.h"

-#ifndef DEV_TTY
-#define DEV_TTY "/dev/tty"
-#endif
-
 /* Unfortunately for debugging, stderr is usually a macro.  This is painful
    when calling functions that take FILE *'s from the debugger.
    So we make a variable which has the same value and which is accessible  
when
@@ -410,45 +405,47 @@ maintenance_print_symbols (char *args, int from_tty)
   char **argv;
   struct ui_file *outfile;
   struct cleanup *cleanups;
-  char *symname = NULL;
-  char *filename = DEV_TTY;
+  char *filename = NULL;
+  char *print_only = NULL;
   struct objfile *objfile;
   struct compunit_symtab *cu;
   struct symtab *s;

   dont_repeat ();

-  if (args == NULL)
-    {
-      error (_("Arguments missing: an output file name "
-	       "and an optional symbol file name"));
-    }
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
-
-  if (argv[0] != NULL)
+  /* Note: gdb_buildargv cannot currently return { NULL },
+     but we play it safe just in case that changes.  */
+  if (argv == NULL || argv[0] == NULL)
     {
-      filename = argv[0];
-      /* If a second arg is supplied, it is a source file name to match  
on.  */
-      if (argv[1] != NULL)
-	{
-	  symname = argv[1];
-	}
+      error (_("\"print symbols\" takes an output file name"
+	       " and an optional symbol file name"));
     }

+  filename = argv[0];
+  /* If a second arg is supplied, it is a source file name to match on.  */
+  if (argv[1] != NULL)
+    print_only = argv[1];
+
   filename = tilde_expand (filename);
   make_cleanup (xfree, filename);

   outfile = gdb_fopen (filename, FOPEN_WT);
-  if (outfile == 0)
+  if (outfile == NULL)
     perror_with_name (filename);
   make_cleanup_ui_file_delete (outfile);

+  if (print_only != NULL)
+    re_comp (print_only);
+
   ALL_FILETABS (objfile, cu, s)
     {
       QUIT;
-      if (symname == NULL
-	  || filename_cmp (symname, symtab_to_filename_for_display (s)) == 0)
+      /* Heads up: While we're looping more symtabs can get expanded  
(e.g., to
+	 process check_typedef).  We'll just ignore them since they're added to
+	 the front of the list, which is ok.  */
+      if (print_only == NULL || re_exec (symtab_to_filename_for_display  
(s)))
 	dump_symtab (objfile, s, outfile);
     }
   do_cleanups (cleanups);
@@ -642,54 +639,44 @@ maintenance_print_msymbols (char *args, int from_tty)
   char **argv;
   struct ui_file *outfile;
   struct cleanup *cleanups;
-  char *filename = DEV_TTY;
-  char *symname = NULL;
-  struct program_space *pspace;
+  char *filename = NULL;
+  char *print_only = NULL;
   struct objfile *objfile;

-  struct stat sym_st, obj_st;
-
   dont_repeat ();

-  if (args == NULL)
-    {
-      error (_("print-msymbols takes an output file "
-	       "name and optional symbol file name"));
-    }
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
-
-  if (argv[0] != NULL)
+  /* Note: gdb_buildargv cannot currently return { NULL },
+     but we play it safe just in case that changes.  */
+  if (argv == NULL || argv[0] == NULL)
     {
-      filename = argv[0];
-      /* If a second arg is supplied, it is a source file name to match  
on.  */
-      if (argv[1] != NULL)
-	{
-	  symname = gdb_realpath (argv[1]);
-	  make_cleanup (xfree, symname);
-	  if (symname && stat (symname, &sym_st))
-	    perror_with_name (symname);
-	}
+      error (_("\"print msymbols\" takes an output file name"
+	       " and an optional objfile name"));
     }

+  filename = argv[0];
+  /* If a second arg is supplied, it is a source file name to match on.  */
+  if (argv[1] != NULL)
+    print_only = argv[1];
+
   filename = tilde_expand (filename);
   make_cleanup (xfree, filename);

   outfile = gdb_fopen (filename, FOPEN_WT);
-  if (outfile == 0)
+  if (outfile == NULL)
     perror_with_name (filename);
   make_cleanup_ui_file_delete (outfile);

-  ALL_PSPACES (pspace)
-    ALL_PSPACE_OBJFILES (pspace, objfile)
-      {
-	QUIT;
-	if (symname == NULL || (!stat (objfile_name (objfile), &obj_st)
-				&& sym_st.st_dev == obj_st.st_dev
-				&& sym_st.st_ino == obj_st.st_ino))
-	  dump_msymbols (objfile, outfile);
-      }
-  fprintf_filtered (outfile, "\n\n");
+  if (print_only != NULL)
+    re_comp (print_only);
+
+  ALL_OBJFILES (objfile)
+  {
+    QUIT;
+    if (print_only == NULL || re_exec (objfile_name (objfile)))
+      dump_msymbols (objfile, outfile);
+  }
   do_cleanups (cleanups);
 }

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index f298172..96171b3 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -16809,10 +16809,12 @@ entered from the keyboard causes symbol  
information to be loaded.
 @cindex partial symbol dump
 @kindex maint print msymbols
 @cindex minimal symbol dump
-@item maint print symbols @var{filename}
-@itemx maint print psymbols @var{filename}
-@itemx maint print msymbols @var{filename}
+@item maint print symbols @var{filename} @r{[} @var{regexp} @r{]}
+@itemx maint print psymbols @var{filename} @r{[} @var{regexp} @r{]}
+@itemx maint print msymbols @var{filename} @r{[} @var{regexp} @r{]}
 Write a dump of debugging symbol data into the file @var{filename}.
+If @var{regexp} is given then only print symbols from files that match
+the regular expression.
 These commands are used to debug the @value{GDBN} symbol-reading code.   
Only
 symbols with debugging data are included.  If you use @samp{maint print
 symbols}, @value{GDBN} includes all the symbols for which it has already