Re: [PATCH 06/11 v5] Add target/symbol.h

[Doug Evans <dje@google.com>]

Gary Benson writes:
 > This adds target/symbol.h.  This file declares a function that the
 > shared code can use and that the clients must implement.  It also
 > changes some shared code to use these functions.
 > 
 > gdb/
 > 2014-08-01  Tom Tromey  <tromey@redhat.com>
 > 	    Gary Benson  <gbenson@redhat.com>
 > 
 > 	* target/symbol.h: New file.
 > 	* Makefile.in (HFILES_NO_SRCDIR): Add target/symbol.h.
 > 	* target.h: Include target/symbol.h.
 > 	* target.c (target_look_up_symbol): New function.
 > 	* common/agent.c: Include target/symbol.h.
 > 	[!GDBSERVER]: Don't include objfiles.h.
 > 	(agent_look_up_symbols): Use target_look_up_symbol.
 > 
 > gdb/gdbserver/
 > 2014-08-01  Tom Tromey  <tromey@redhat.com>
 > 	    Gary Benson  <gbenson@redhat.com>
 > 
 > 	* target.c: Include target/symbol.h.
 > 	(target_look_up_symbol): New function.
 > [...]
 > diff --git a/gdb/target/symbol.h b/gdb/target/symbol.h
 > new file mode 100644
 > index 0000000..bb37b72
 > --- /dev/null
 > +++ b/gdb/target/symbol.h
 > @@ -0,0 +1,36 @@
 > +/* Declarations of target symbol functions.
 > +
 > +   Copyright (C) 1986-2014 Free Software Foundation, Inc.
 > +
 > +   This file is part of GDB.
 > +
 > +   This program is free software; you can redistribute it and/or modify
 > +   it under the terms of the GNU General Public License as published by
 > +   the Free Software Foundation; either version 3 of the License, or
 > +   (at your option) any later version.
 > +
 > +   This program is distributed in the hope that it will be useful,
 > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
 > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 > +   GNU General Public License for more details.
 > +
 > +   You should have received a copy of the GNU General Public License
 > +   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 > +
 > +#ifndef TARGET_SYMBOL_H
 > +#define TARGET_SYMBOL_H
 > +
 > +struct objfile;
 > +
 > +/* Find a symbol that matches NAME.  Limit the search to OBJFILE if
 > +   OBJFILE is non-NULL and the implementation supports limiting the
 > +   search to specific object files.  If a match is found, store the
 > +   matching symbol's address in ADDR and return nonzero.  Return zero
 > +   if no symbol matching NAME is found.  Raise an exception if OBJFILE
 > +   is non-NULL and the implementation does not support limiting
 > +   searches to specific object files.  */
 > +
 > +extern int target_look_up_symbol (const char *name, CORE_ADDR *addr,
 > +				  struct objfile *objfile);
 > +
 > +#endif /* TARGET_SYMBOL_H */
 > -- 
 > 1.7.1

Can this comment spell out that either a mangled or demangled
form of the symbol is allowed for NAME?
[assuming that that is indeed the case]

Also, the target/target.h memory routines return zero for success
and a non-zero error code for failure.  E.g.,

+/* Read LEN bytes of target memory at address MEMADDR, placing the
+   results in GDB's memory at MYADDR.  Return zero for success,
+   nonzero if any error occurs.  Implementations of this function may
+   define and use their own error codes, but functions in the common,
+   nat and target directories must treat the return code as opaque.
+   No guarantee is made about the contents of the data at MYADDR if
+   any error occurs.  */
+
+extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr,
+			       ssize_t len);

Do we want to be consistent here, and have the same results for
target_look_up_symbol? [and throughout the target API]