From patchwork Wed Apr 5 12:58:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pedro Alves X-Patchwork-Id: 19862 Received: (qmail 70231 invoked by alias); 5 Apr 2017 12:58:08 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 68669 invoked by uid 89); 5 Apr 2017 12:58:07 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-23.7 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_LAZY_DOMAIN_SECURITY, RCVD_IN_DNSWL_NONE, RCVD_IN_SORBS_SPAM autolearn=ham version=3.3.2 spammy= X-HELO: mail-wr0-f182.google.com Received: from mail-wr0-f182.google.com (HELO mail-wr0-f182.google.com) (209.85.128.182) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 05 Apr 2017 12:58:04 +0000 Received: by mail-wr0-f182.google.com with SMTP id w11so12704487wrc.3 for ; Wed, 05 Apr 2017 05:58:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=4aqMAfStKUw05QXogjn5Pmfv7O6fIAZh3Q+lJPQUYrY=; b=fdZRofHbpwfA9kIPXhyov8bvw349ttZsQwbVjO+g0jkXQbkA+7f2aXXvcm/MwrIdDg BAZsn0DL3cL3xjn3PQhA4jcLWY2QhDHDtdwzySVRpKPk4WXaSryvmCJ+L+f/Z6qYlYCP 7lhzzlrEexFA/YzJZehyFeaKBC1NSViBv5s2ALi3ETyu926TY0KpoEVpYHVqrlzOWTsq +BEdwkzpxkyVy743tqf9QCKP9e/B9hVyYw3zG7qbBXe0OnfXptc2H+T7TmlPT0na1GaB 8dI50Am1mgnBPtkwGm+ItLEp3ffo9aGatfi7oTRTt5HRzxc1oYbaJEJNgjlvHlps5Fhi 20qg== X-Gm-Message-State: AFeK/H1jLTrroThVmHVjWWmNUJFj6DhvQBCyn97F028d1TSTJFs2Qs19 cKTEHaHPFrUo4jas X-Received: by 10.28.109.147 with SMTP id b19mr19509313wmi.69.1491397082242; Wed, 05 Apr 2017 05:58:02 -0700 (PDT) Received: from [192.168.0.100] ([37.189.166.198]) by smtp.gmail.com with ESMTPSA id l90sm22316084wmi.25.2017.04.05.05.58.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 05 Apr 2017 05:58:01 -0700 (PDT) Subject: Re: [PATCH 14/18] -Wwrite-strings: Add a PyArg_ParseTupleAndKeywords "const char *" overload To: Sergio Durigan Junior References: <1491326751-16180-1-git-send-email-palves@redhat.com> <1491326751-16180-15-git-send-email-palves@redhat.com> <87efx8dnnr.fsf@redhat.com> Cc: gdb-patches@sourceware.org From: Pedro Alves Message-ID: <899ec58d-2b0c-f237-e1b7-91eb02e76d82@redhat.com> Date: Wed, 5 Apr 2017 13:58:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <87efx8dnnr.fsf@redhat.com> On 04/04/2017 07:37 PM, Sergio Durigan Junior wrote: > On Tuesday, April 04 2017, Pedro Alves wrote: >> However, to avoid having all callers add the 'const_cast' >> themselves, this commit define a PyArg_ParseTupleAndKeywords overload >> here with a corresponding 'keywords' parameter type that does the cast >> in a single place. >> >> As in the PyGetSetDef patch, I'd be fine with naming this >> gdb_PyArg_ParseTupleAndKeywords instead, if people would find having >> our own overload confusing. > > As much as I like the overloading approach in general, I prefer to see > our own overloads marked with the "gdb_", just to make things clearer. OK, updated patch below. WDYT? > >> BTW, this API issue was discussed years ago in the python-dev list: >> >> https://mail.python.org/pipermail/python-dev/2006-February/060689.html >> >> ... and an overload for C++ was suggested in there somewhere. >> Unfortunately, it was never added. > > Interesting. I wonder if there's an actual bug/issue opened on their > bugzilla about this. > > Hm, after a quick search I didn't find anything. Maybe it's worth > creating one. I had found that thread via this bug: https://bugs.python.org/issue1772673 From 2ea02b3a4f5e7e0a1ecfb206d8a5f04b37876bd2 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Wed, 5 Apr 2017 13:45:55 +0100 Subject: [PATCH] -Wwrite-strings: Add a PyArg_ParseTupleAndKeywords "const char *" overload -Wwrite-strings flags code like: static char *keywords[] = {"command", "from_tty", "to_string", NULL }; as needing "(char *)" casts, because string literals are "const char []". We can get rid of the casts by changing the array type like this: - static char *keywords[] = {"command", "from_tty", "to_string", NULL }; + static const char *keywords[] = {"command", "from_tty", "to_string", NULL }; However, passing the such array to PyArg_ParseTupleAndKeywords no longer works OOTB, because PyArg_ParseTupleAndKeywords expects a "char **": PyArg_ParseTupleAndKeywords(PyObject *args, PyObject *kw, const char *format, char *keywords[], ...); and "const char **" is not implicitly convertible to "char **". C++ is more tolerant that C here WRT aliasing, and a const_cast is fine. However, to avoid having all callers do the cast themselves, this commit defines a gdb_PyArg_ParseTupleAndKeywords function here with a corresponding 'keywords' parameter type that does the cast in a single place. gdb/ChangeLog: yyyy-mm-dd Pedro Alves * python/python-internal.h (gdb_PyArg_ParseTupleAndKeywords): New static inline function. * python/py-arch.c (archpy_disassemble): Constify 'keywords' array and use gdb_PyArg_ParseTupleAndKeywords. * python/py-cmd.c (cmdpy_init): Likewise. * python/py-finishbreakpoint.c (bpfinishpy_init): Likewise. * python/py-inferior.c (infpy_read_memory, infpy_write_memory) (infpy_search_memory): Likewise. * python/py-objfile.c (objfpy_add_separate_debug_file) (gdbpy_lookup_objfile): Likewise. * python/py-symbol.c (gdbpy_lookup_symbol) (gdbpy_lookup_global_symbol): Likewise. * python/py-type.c (gdbpy_lookup_type): Likewise. * python/py-value.c (valpy_lazy_string, valpy_string): Likewise. * python/python.c (execute_gdb_command, gdbpy_write, gdbpy_flush): Likewise. --- gdb/python/py-arch.c | 7 ++++--- gdb/python/py-breakpoint.c | 10 +++++----- gdb/python/py-cmd.c | 10 +++++----- gdb/python/py-finishbreakpoint.c | 6 +++--- gdb/python/py-inferior.c | 21 ++++++++++----------- gdb/python/py-objfile.c | 10 +++++----- gdb/python/py-symbol.c | 13 +++++++------ gdb/python/py-type.c | 6 +++--- gdb/python/py-value.c | 12 ++++++------ gdb/python/python-internal.h | 28 ++++++++++++++++++++++++++++ gdb/python/python.c | 20 ++++++++++---------- 11 files changed, 86 insertions(+), 57 deletions(-) diff --git a/gdb/python/py-arch.c b/gdb/python/py-arch.c index 71d2989..cfadb47 100644 --- a/gdb/python/py-arch.c +++ b/gdb/python/py-arch.c @@ -116,7 +116,7 @@ archpy_name (PyObject *self, PyObject *args) static PyObject * archpy_disassemble (PyObject *self, PyObject *args, PyObject *kw) { - static char *keywords[] = { "start_pc", "end_pc", "count", NULL }; + static const char *keywords[] = { "start_pc", "end_pc", "count", NULL }; CORE_ADDR start, end = 0; CORE_ADDR pc; gdb_py_ulongest start_temp; @@ -126,8 +126,9 @@ archpy_disassemble (PyObject *self, PyObject *args, PyObject *kw) ARCHPY_REQUIRE_VALID (self, gdbarch); - if (!PyArg_ParseTupleAndKeywords (args, kw, GDB_PY_LLU_ARG "|OO", keywords, - &start_temp, &end_obj, &count_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, GDB_PY_LLU_ARG "|OO", + keywords, &start_temp, &end_obj, + &count_obj)) return NULL; start = start_temp; diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c index 34f46fb..a08501e 100644 --- a/gdb/python/py-breakpoint.c +++ b/gdb/python/py-breakpoint.c @@ -637,8 +637,8 @@ bppy_get_ignore_count (PyObject *self, void *closure) static int bppy_init (PyObject *self, PyObject *args, PyObject *kwargs) { - static char *keywords[] = { "spec", "type", "wp_class", "internal", - "temporary", NULL }; + static const char *keywords[] = { "spec", "type", "wp_class", "internal", + "temporary", NULL }; const char *spec; int type = bp_breakpoint; int access_type = hw_write; @@ -647,9 +647,9 @@ bppy_init (PyObject *self, PyObject *args, PyObject *kwargs) int internal_bp = 0; int temporary_bp = 0; - if (! PyArg_ParseTupleAndKeywords (args, kwargs, "s|iiOO", keywords, - &spec, &type, &access_type, - &internal, &temporary)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kwargs, "s|iiOO", keywords, + &spec, &type, &access_type, + &internal, &temporary)) return -1; if (internal) diff --git a/gdb/python/py-cmd.c b/gdb/python/py-cmd.c index 3aaf7f9..3e60673 100644 --- a/gdb/python/py-cmd.c +++ b/gdb/python/py-cmd.c @@ -490,8 +490,8 @@ cmdpy_init (PyObject *self, PyObject *args, PyObject *kw) char *docstring = NULL; struct cmd_list_element **cmd_list; char *cmd_name, *pfx_name; - static char *keywords[] = { "name", "command_class", "completer_class", - "prefix", NULL }; + static const char *keywords[] = { "name", "command_class", "completer_class", + "prefix", NULL }; PyObject *is_prefix = NULL; int cmp; @@ -504,9 +504,9 @@ cmdpy_init (PyObject *self, PyObject *args, PyObject *kw) return -1; } - if (! PyArg_ParseTupleAndKeywords (args, kw, "si|iO", - keywords, &name, &cmdtype, - &completetype, &is_prefix)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "si|iO", + keywords, &name, &cmdtype, + &completetype, &is_prefix)) return -1; if (cmdtype != no_class && cmdtype != class_run diff --git a/gdb/python/py-finishbreakpoint.c b/gdb/python/py-finishbreakpoint.c index 76189b8..06f6ff9 100644 --- a/gdb/python/py-finishbreakpoint.c +++ b/gdb/python/py-finishbreakpoint.c @@ -156,7 +156,7 @@ bpfinishpy_post_stop_hook (struct gdbpy_breakpoint_object *bp_obj) static int bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs) { - static char *keywords[] = { "frame", "internal", NULL }; + static const char *keywords[] = { "frame", "internal", NULL }; struct finish_breakpoint_object *self_bpfinish = (struct finish_breakpoint_object *) self; PyObject *frame_obj = NULL; @@ -169,8 +169,8 @@ bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs) CORE_ADDR pc; struct symbol *function; - if (!PyArg_ParseTupleAndKeywords (args, kwargs, "|OO", keywords, - &frame_obj, &internal)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kwargs, "|OO", keywords, + &frame_obj, &internal)) return -1; TRY diff --git a/gdb/python/py-inferior.c b/gdb/python/py-inferior.c index 77fc543..41bedb5 100644 --- a/gdb/python/py-inferior.c +++ b/gdb/python/py-inferior.c @@ -435,10 +435,10 @@ infpy_read_memory (PyObject *self, PyObject *args, PyObject *kw) CORE_ADDR addr, length; gdb_byte *buffer = NULL; PyObject *addr_obj, *length_obj, *result; - static char *keywords[] = { "address", "length", NULL }; + static const char *keywords[] = { "address", "length", NULL }; - if (! PyArg_ParseTupleAndKeywords (args, kw, "OO", keywords, - &addr_obj, &length_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "OO", keywords, + &addr_obj, &length_obj)) return NULL; if (get_addr_from_python (addr_obj, &addr) < 0 @@ -494,13 +494,12 @@ infpy_write_memory (PyObject *self, PyObject *args, PyObject *kw) const gdb_byte *buffer; CORE_ADDR addr, length; PyObject *addr_obj, *length_obj = NULL; - static char *keywords[] = { "address", "buffer", "length", NULL }; + static const char *keywords[] = { "address", "buffer", "length", NULL }; #ifdef IS_PY3K Py_buffer pybuf; - if (! PyArg_ParseTupleAndKeywords (args, kw, "Os*|O", keywords, - &addr_obj, &pybuf, - &length_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "Os*|O", keywords, + &addr_obj, &pybuf, &length_obj)) return NULL; buffer = (const gdb_byte *) pybuf.buf; @@ -643,7 +642,7 @@ infpy_search_memory (PyObject *self, PyObject *args, PyObject *kw) { struct gdb_exception except = exception_none; CORE_ADDR start_addr, length; - static char *keywords[] = { "address", "length", "pattern", NULL }; + static const char *keywords[] = { "address", "length", "pattern", NULL }; PyObject *start_addr_obj, *length_obj; Py_ssize_t pattern_size; const gdb_byte *buffer; @@ -652,9 +651,9 @@ infpy_search_memory (PyObject *self, PyObject *args, PyObject *kw) #ifdef IS_PY3K Py_buffer pybuf; - if (! PyArg_ParseTupleAndKeywords (args, kw, "OOs*", keywords, - &start_addr_obj, &length_obj, - &pybuf)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "OOs*", keywords, + &start_addr_obj, &length_obj, + &pybuf)) return NULL; buffer = (const gdb_byte *) pybuf.buf; diff --git a/gdb/python/py-objfile.c b/gdb/python/py-objfile.c index 6a47c17..52f2e1f 100644 --- a/gdb/python/py-objfile.c +++ b/gdb/python/py-objfile.c @@ -432,13 +432,13 @@ objfpy_is_valid (PyObject *self, PyObject *args) static PyObject * objfpy_add_separate_debug_file (PyObject *self, PyObject *args, PyObject *kw) { - static char *keywords[] = { "file_name", NULL }; + static const char *keywords[] = { "file_name", NULL }; objfile_object *obj = (objfile_object *) self; const char *file_name; OBJFPY_REQUIRE_VALID (obj); - if (!PyArg_ParseTupleAndKeywords (args, kw, "s", keywords, &file_name)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s", keywords, &file_name)) return NULL; TRY @@ -559,14 +559,14 @@ objfpy_lookup_objfile_by_build_id (const char *build_id) PyObject * gdbpy_lookup_objfile (PyObject *self, PyObject *args, PyObject *kw) { - static char *keywords[] = { "name", "by_build_id", NULL }; + static const char *keywords[] = { "name", "by_build_id", NULL }; const char *name; PyObject *by_build_id_obj = NULL; int by_build_id; struct objfile *objfile; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O!", keywords, - &name, &PyBool_Type, &by_build_id_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|O!", keywords, + &name, &PyBool_Type, &by_build_id_obj)) return NULL; by_build_id = 0; diff --git a/gdb/python/py-symbol.c b/gdb/python/py-symbol.c index 05b002f..c9f83a3 100644 --- a/gdb/python/py-symbol.c +++ b/gdb/python/py-symbol.c @@ -373,13 +373,14 @@ gdbpy_lookup_symbol (PyObject *self, PyObject *args, PyObject *kw) int domain = VAR_DOMAIN; struct field_of_this_result is_a_field_of_this; const char *name; - static char *keywords[] = { "name", "block", "domain", NULL }; + static const char *keywords[] = { "name", "block", "domain", NULL }; struct symbol *symbol = NULL; PyObject *block_obj = NULL, *sym_obj, *bool_obj; const struct block *block = NULL; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O!i", keywords, &name, - &block_object_type, &block_obj, &domain)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|O!i", keywords, &name, + &block_object_type, &block_obj, + &domain)) return NULL; if (block_obj) @@ -443,12 +444,12 @@ gdbpy_lookup_global_symbol (PyObject *self, PyObject *args, PyObject *kw) { int domain = VAR_DOMAIN; const char *name; - static char *keywords[] = { "name", "domain", NULL }; + static const char *keywords[] = { "name", "domain", NULL }; struct symbol *symbol = NULL; PyObject *sym_obj; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|i", keywords, &name, - &domain)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|i", keywords, &name, + &domain)) return NULL; TRY diff --git a/gdb/python/py-type.c b/gdb/python/py-type.c index 12b6310..aa20d4c 100644 --- a/gdb/python/py-type.c +++ b/gdb/python/py-type.c @@ -1347,14 +1347,14 @@ type_object_to_type (PyObject *obj) PyObject * gdbpy_lookup_type (PyObject *self, PyObject *args, PyObject *kw) { - static char *keywords[] = { "name", "block", NULL }; + static const char *keywords[] = { "name", "block", NULL }; const char *type_name = NULL; struct type *type = NULL; PyObject *block_obj = NULL; const struct block *block = NULL; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O", keywords, - &type_name, &block_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|O", keywords, + &type_name, &block_obj)) return NULL; if (block_obj) diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c index 9c0470f..b5a0ef8 100644 --- a/gdb/python/py-value.c +++ b/gdb/python/py-value.c @@ -431,11 +431,11 @@ valpy_lazy_string (PyObject *self, PyObject *args, PyObject *kw) gdb_py_longest length = -1; struct value *value = ((value_object *) self)->value; const char *user_encoding = NULL; - static char *keywords[] = { "encoding", "length", NULL }; + static const char *keywords[] = { "encoding", "length", NULL }; PyObject *str_obj = NULL; - if (!PyArg_ParseTupleAndKeywords (args, kw, "|s" GDB_PY_LL_ARG, keywords, - &user_encoding, &length)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "|s" GDB_PY_LL_ARG, + keywords, &user_encoding, &length)) return NULL; if (length < -1) @@ -526,10 +526,10 @@ valpy_string (PyObject *self, PyObject *args, PyObject *kw) const char *user_encoding = NULL; const char *la_encoding = NULL; struct type *char_type; - static char *keywords[] = { "encoding", "errors", "length", NULL }; + static const char *keywords[] = { "encoding", "errors", "length", NULL }; - if (!PyArg_ParseTupleAndKeywords (args, kw, "|ssi", keywords, - &user_encoding, &errors, &length)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "|ssi", keywords, + &user_encoding, &errors, &length)) return NULL; TRY diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h index d4ed170..db75002 100644 --- a/gdb/python/python-internal.h +++ b/gdb/python/python-internal.h @@ -316,6 +316,34 @@ struct gdb_PyGetSetDef : PyGetSetDef {} }; +/* The 'keywords' parameter of PyArg_ParseTupleAndKeywords has type + 'char **'. However, string literals are const in C++, and so to + avoid casting at every keyword array definition, we'll need to make + the keywords array an array of 'const char *'. To avoid having all + callers add a 'const_cast' themselves when passing such an + array through 'char **', we define our own version of + PyArg_ParseTupleAndKeywords here with a corresponding 'keywords' + parameter type that does the cast in a single place. (This is not + an overload of PyArg_ParseTupleAndKeywords in order to make it + clearer that we're calling our own function instead of a function + that exists in some newer Python version.) */ + +static inline int +gdb_PyArg_ParseTupleAndKeywords (PyObject *args, PyObject *kw, + const char *format, const char **keywords, ...) +{ + va_list ap; + int res; + + va_start (ap, keywords); + res = PyArg_VaParseTupleAndKeywords (args, kw, format, + const_cast (keywords), + ap); + va_end (ap); + + return res; +} + /* In order to be able to parse symtab_and_line_to_sal_object function a real symtab_and_line structure is needed. */ #include "symtab.h" diff --git a/gdb/python/python.c b/gdb/python/python.c index a7aff53..25f475f 100644 --- a/gdb/python/python.c +++ b/gdb/python/python.c @@ -572,11 +572,11 @@ execute_gdb_command (PyObject *self, PyObject *args, PyObject *kw) const char *arg; PyObject *from_tty_obj = NULL, *to_string_obj = NULL; int from_tty, to_string; - static char *keywords[] = {"command", "from_tty", "to_string", NULL }; + static const char *keywords[] = { "command", "from_tty", "to_string", NULL }; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O!O!", keywords, &arg, - &PyBool_Type, &from_tty_obj, - &PyBool_Type, &to_string_obj)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|O!O!", keywords, &arg, + &PyBool_Type, &from_tty_obj, + &PyBool_Type, &to_string_obj)) return NULL; from_tty = 0; @@ -1047,11 +1047,11 @@ static PyObject * gdbpy_write (PyObject *self, PyObject *args, PyObject *kw) { const char *arg; - static char *keywords[] = {"text", "stream", NULL }; + static const char *keywords[] = { "text", "stream", NULL }; int stream_type = 0; - if (! PyArg_ParseTupleAndKeywords (args, kw, "s|i", keywords, &arg, - &stream_type)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|i", keywords, &arg, + &stream_type)) return NULL; TRY @@ -1088,11 +1088,11 @@ gdbpy_write (PyObject *self, PyObject *args, PyObject *kw) static PyObject * gdbpy_flush (PyObject *self, PyObject *args, PyObject *kw) { - static char *keywords[] = {"stream", NULL }; + static const char *keywords[] = { "stream", NULL }; int stream_type = 0; - if (! PyArg_ParseTupleAndKeywords (args, kw, "|i", keywords, - &stream_type)) + if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "|i", keywords, + &stream_type)) return NULL; switch (stream_type)