From a7c0469f992721b30665ba92f4f2f74d29032a84 Mon Sep 17 00:00:00 2001 From: Doug Evans Date: Wed, 15 Mar 2017 15:44:45 -0700 Subject: [PATCH] Copy lazy string handling fixes from Python. This patch keeps the Scheme side of lazy string handling in sync with the python size, bringing over fixes for PRs python/17728, python/18439, python/18779. gdb/ChangeLog: * guile/scm-lazy-string.c (lazy_string_smob): Clarify use of LENGTH member. Change type of TYPE member to SCM. All uses updated. (lsscm_make_lazy_string_smob): Add assert. (lsscm_make_lazy_string): Flag bad length values. (lsscm_elt_type): New function. (gdbscm_lazy_string_to_value): Rewrite to use lsscm_safe_lazy_string_to_value. (lsscm_safe_lazy_string_to_value): Fix handling of TYPE_CODE_PTR. * guile/scm-value.c (gdbscm_value_to_lazy_string): Flag bad length values. Fix TYPE_CODE_PTR. Handle TYPE_CODE_ARRAY. Handle typedefs in incoming type. * guile/guile-internal.h (tyscm_scm_to_type): Declare. * guile/scm-type.c (tyscm_scm_to_type): New function. gdb/testsuite/ChangeLog: * gdb.guile/scm-value.c (main) Delete locals sptr, sn. * gdb.guile/scm-lazy-string.c: New file. * gdb.guile/scm-value.exp: Move lazy string tests to ... * gdb.guile/scm-lazy-string.exp: ... here, new file. Add more tests for pointer, array, typedef lazy strings. --- gdb/ChangeLog | 16 +++ gdb/guile/scm-lazy-string.c | 119 ++++++++++++++------ gdb/guile/scm-value.c | 65 ++++++++++- gdb/testsuite/ChangeLog | 8 ++ gdb/testsuite/gdb.guile/scm-lazy-string.c | 29 +++++ gdb/testsuite/gdb.guile/scm-lazy-string.exp | 82 ++++++++++++++ gdb/testsuite/gdb.guile/scm-value.c | 2 - gdb/testsuite/gdb.guile/scm-value.exp | 31 ----- 8 files changed, 278 insertions(+), 74 deletions(-) create mode 100644 gdb/testsuite/gdb.guile/scm-lazy-string.c create mode 100644 gdb/testsuite/gdb.guile/scm-lazy-string.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 7541627fd7f..0c3017bce03 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,21 @@ 2017-03-16 Doug Evans + * guile/scm-lazy-string.c (lazy_string_smob): Clarify use of LENGTH + member. Change type of TYPE member to SCM. All uses updated. + (lsscm_make_lazy_string_smob): Add assert. + (lsscm_make_lazy_string): Flag bad length values. + (lsscm_elt_type): New function. + (gdbscm_lazy_string_to_value): Rewrite to use + lsscm_safe_lazy_string_to_value. + (lsscm_safe_lazy_string_to_value): Fix handling of TYPE_CODE_PTR. + * guile/scm-value.c (gdbscm_value_to_lazy_string): Flag bad length + values. Fix TYPE_CODE_PTR. Handle TYPE_CODE_ARRAY. Handle typedefs + in incoming type. + * guile/guile-internal.h (tyscm_scm_to_type): Declare. + * guile/scm-type.c (tyscm_scm_to_type): New function. + +2017-03-15 Doug Evans + PR python/17728, python/18439, python/18779 * python/py-lazy-string.c (lazy_string_object): Clarify use of LENGTH member. Change type of TYPE member to PyObject *. All uses updated. diff --git a/gdb/guile/scm-lazy-string.c b/gdb/guile/scm-lazy-string.c index d4eaa7a8314..0a646286e8a 100644 --- a/gdb/guile/scm-lazy-string.c +++ b/gdb/guile/scm-lazy-string.c @@ -44,14 +44,20 @@ typedef struct freed. */ char *encoding; - /* Holds the length of the string in characters. If the length is -1, - then the string will be fetched and encoded up to the first null of - appropriate width. */ + /* If TYPE is an array: If the length is known, then this value is the + array's length, otherwise it is -1. + If TYPE is not an array: Then this value represents the string's length. + In either case, if the value is -1 then the string will be fetched and + encoded up to the first null of appropriate width. */ int length; - /* This attribute holds the type that is represented by the lazy - string's type. */ - struct type *type; + /* The type of the string. + For example if the lazy string was created from a C "char*" then TYPE + represents a C "char*". To get the type of the character in the string + call lsscm_elt_type which handles the different kinds of values for TYPE. + This is recorded as an SCM object so that we take advantage of support for + preserving the type should its owning objfile go away. */ + SCM type; } lazy_string_smob; static const char lazy_string_smob_name[] = "gdb:lazy-string"; @@ -95,7 +101,10 @@ lsscm_print_lazy_string_smob (SCM self, SCM port, scm_print_state *pstate) } /* Low level routine to create a object. - The caller must verify !(address == 0 && length != 0). */ + The caller must verify: + - length >= -1 + - !(address == 0 && length != 0) + - type != NULL */ static SCM lsscm_make_lazy_string_smob (CORE_ADDR address, int length, @@ -105,18 +114,17 @@ lsscm_make_lazy_string_smob (CORE_ADDR address, int length, scm_gc_malloc (sizeof (lazy_string_smob), lazy_string_smob_name); SCM ls_scm; - /* Caller must verify this. */ + gdb_assert (length >= -1); gdb_assert (!(address == 0 && length != 0)); gdb_assert (type != NULL); ls_smob->address = address; - /* Coerce all values < 0 to -1. */ - ls_smob->length = length < 0 ? -1 : length; + ls_smob->length = length; if (encoding == NULL || strcmp (encoding, "") == 0) ls_smob->encoding = NULL; else ls_smob->encoding = xstrdup (encoding); - ls_smob->type = type; + ls_smob->type = tyscm_scm_from_type (type); ls_scm = scm_new_smob (lazy_string_smob_tag, (scm_t_bits) ls_smob); gdbscm_init_gsmob (&ls_smob->base); @@ -147,11 +155,18 @@ SCM lsscm_make_lazy_string (CORE_ADDR address, int length, const char *encoding, struct type *type) { + if (length < -1) + { + return gdbscm_make_out_of_range_error (NULL, 0, + scm_from_int (length), + _("invalid length")); + } + if (address == 0 && length != 0) { return gdbscm_make_out_of_range_error (NULL, 0, scm_from_int (length), - _("cannot create a lazy string with address 0x0" + _("cannot create a lazy string with address 0x0," " and a non-zero length")); } @@ -175,6 +190,28 @@ lsscm_get_lazy_string_arg_unsafe (SCM self, int arg_pos, const char *func_name) return self; } + +/* Return the type of a character in lazy string LS_SMOB. */ + +static struct type * +lsscm_elt_type (lazy_string_smob *ls_smob) +{ + struct type *type = tyscm_scm_to_type (ls_smob->type); + struct type *realtype; + + realtype = check_typedef (type); + + switch (TYPE_CODE (realtype)) + { + case TYPE_CODE_PTR: + case TYPE_CODE_ARRAY: + return TYPE_TARGET_TYPE (realtype); + default: + /* This is done to preserve existing behaviour. PR 20769. + E.g., gdb.parse_and_eval("my_int_variable").lazy_string().type. */ + return realtype; + } +} /* Lazy string methods. */ @@ -223,7 +260,7 @@ gdbscm_lazy_string_type (SCM self) SCM ls_scm = lsscm_get_lazy_string_arg_unsafe (self, SCM_ARG1, FUNC_NAME); lazy_string_smob *ls_smob = (lazy_string_smob *) SCM_SMOB_DATA (ls_scm); - return tyscm_scm_from_type (ls_smob->type); + return ls_smob->type; } /* (lazy-string->value ) -> */ @@ -232,25 +269,13 @@ static SCM gdbscm_lazy_string_to_value (SCM self) { SCM ls_scm = lsscm_get_lazy_string_arg_unsafe (self, SCM_ARG1, FUNC_NAME); - lazy_string_smob *ls_smob = (lazy_string_smob *) SCM_SMOB_DATA (ls_scm); - struct value *value = NULL; - - if (ls_smob->address == 0) - { - gdbscm_throw (gdbscm_make_out_of_range_error (FUNC_NAME, SCM_ARG1, self, - _("cannot create a value from NULL"))); - } - - TRY - { - value = value_at_lazy (ls_smob->type, ls_smob->address); - } - CATCH (except, RETURN_MASK_ALL) - { - GDBSCM_HANDLE_GDB_EXCEPTION (except); - } - END_CATCH + SCM except_scm; + struct value *value; + value = lsscm_safe_lazy_string_to_value (ls_scm, SCM_ARG1, FUNC_NAME, + &except_scm); + if (value == NULL) + gdbscm_throw (except_scm); return vlscm_scm_from_value (value); } @@ -275,19 +300,41 @@ lsscm_safe_lazy_string_to_value (SCM string, int arg_pos, gdb_assert (lsscm_is_lazy_string (string)); ls_smob = (lazy_string_smob *) SCM_SMOB_DATA (string); - *except_scmp = SCM_BOOL_F; if (ls_smob->address == 0) { *except_scmp - = gdbscm_make_out_of_range_error (FUNC_NAME, SCM_ARG1, string, + = gdbscm_make_out_of_range_error (func_name, arg_pos, string, _("cannot create a value from NULL")); return NULL; } TRY { - value = value_at_lazy (ls_smob->type, ls_smob->address); + struct type *type = tyscm_scm_to_type (ls_smob->type); + struct type *realtype = check_typedef (type); + + switch (TYPE_CODE (realtype)) + { + case TYPE_CODE_PTR: + /* If a length is specified we need to convert this to an array + of the specified size. */ + if (ls_smob->length != -1) + { + /* PR 20786: There's no way to specify an array of length zero. + Record a length of [0,-1] which is how Ada does it. Anything + we do is broken, but this one possible solution. */ + type = lookup_array_range_type (TYPE_TARGET_TYPE (realtype), + 0, ls_smob->length - 1); + value = value_at_lazy (type, ls_smob->address); + } + else + value = value_from_pointer (type, ls_smob->address); + break; + default: + value = value_at_lazy (type, ls_smob->address); + break; + } } CATCH (except, RETURN_MASK_ALL) { @@ -307,12 +354,14 @@ lsscm_val_print_lazy_string (SCM string, struct ui_file *stream, const struct value_print_options *options) { lazy_string_smob *ls_smob; + struct type *elt_type; gdb_assert (lsscm_is_lazy_string (string)); ls_smob = (lazy_string_smob *) SCM_SMOB_DATA (string); + elt_type = lsscm_elt_type (ls_smob); - val_print_string (ls_smob->type, ls_smob->encoding, + val_print_string (elt_type, ls_smob->encoding, ls_smob->address, ls_smob->length, stream, options); } diff --git a/gdb/guile/scm-value.c b/gdb/guile/scm-value.c index ebccfb6d668..f81a90cb0d9 100644 --- a/gdb/guile/scm-value.c +++ b/gdb/guile/scm-value.c @@ -1173,8 +1173,10 @@ gdbscm_value_to_string (SCM self, SCM rest) Return a Scheme object representing a lazy_string_object type. A lazy string is a pointer to a string with an optional encoding and length. If ENCODING is not given, the target's charset is used. - If LENGTH is provided then the length parameter is set to LENGTH, otherwise - length will be set to -1 (first null of appropriate with). + If LENGTH is provided then the length parameter is set to LENGTH. + Otherwise if the value is an array of known length then the array's length + is used. Otherwise the length will be set to -1 (meaning first null of + appropriate with). LENGTH must be a Scheme integer, it can't be a integer. */ static SCM @@ -1198,18 +1200,69 @@ gdbscm_value_to_lazy_string (SCM self, SCM rest) &encoding_arg_pos, &encoding, &length_arg_pos, &length); + if (length < -1) + { + gdbscm_out_of_range_error (FUNC_NAME, length_arg_pos, + scm_from_int (length), + _("invalid length")); + } + cleanups = make_cleanup (xfree, encoding); TRY { struct cleanup *inner_cleanup = make_cleanup_value_free_to_mark (value_mark ()); + struct type *type, *realtype; + CORE_ADDR addr; - if (TYPE_CODE (value_type (value)) == TYPE_CODE_PTR) - value = value_ind (value); + type = value_type (value); + realtype = check_typedef (type); + + switch (TYPE_CODE (realtype)) + { + case TYPE_CODE_ARRAY: + { + LONGEST array_length = -1; + LONGEST low_bound, high_bound; + + /* PR 20786: There's no way to specify an array of length zero. + Record a length of [0,-1] which is how Ada does it. Anything + we do is broken, but this one possible solution. */ + if (get_array_bounds (realtype, &low_bound, &high_bound)) + array_length = high_bound - low_bound + 1; + if (length == -1) + length = array_length; + else if (array_length == -1) + { + type = lookup_array_range_type (TYPE_TARGET_TYPE (realtype), + 0, length - 1); + } + else if (length != array_length) + { + /* We need to create a new array type with the + specified length. */ + if (length > array_length) + error (_("length is larger than array size")); + type = lookup_array_range_type (TYPE_TARGET_TYPE (type), + low_bound, + low_bound + length - 1); + } + addr = value_address (value); + break; + } + case TYPE_CODE_PTR: + /* If a length is specified we defer creating an array of the + specified width until we need to. */ + addr = value_as_address (value); + break; + default: + /* Should flag an error here. PR 20769. */ + addr = value_address (value); + break; + } - result = lsscm_make_lazy_string (value_address (value), length, - encoding, value_type (value)); + result = lsscm_make_lazy_string (addr, length, encoding, type); do_cleanups (inner_cleanup); } diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 92138a4a4eb..39ff712e74b 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -4,6 +4,14 @@ * gdb.cp/m-static.exp: Fix expectation for prototype of test5.single_constructor and single_constructor::single_constructor. ======= +2017-03-15 Doug Evans + + * gdb.guile/scm-value.c (main) Delete locals sptr, sn. + * gdb.guile/scm-lazy-string.c: New file. + * gdb.guile/scm-value.exp: Move lazy string tests to ... + * gdb.guile/scm-lazy-string.exp: ... here, new file. Add more tests + for pointer, array, typedef lazy strings. + 2017-03-15 Doug Evans PR python/17728, python/18439, python/18779 diff --git a/gdb/testsuite/gdb.guile/scm-lazy-string.c b/gdb/testsuite/gdb.guile/scm-lazy-string.c new file mode 100644 index 00000000000..936b4e2b253 --- /dev/null +++ b/gdb/testsuite/gdb.guile/scm-lazy-string.c @@ -0,0 +1,29 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2015-2016 Free Software Foundation, Inc. + + 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 . */ + +typedef const char *pointer; + +int +main () +{ + const char *ptr = "pointer"; + const char array[] = "array"; + pointer typedef_ptr = "typedef pointer"; + const char *null = 0; + + return 0; /* break here */ +} diff --git a/gdb/testsuite/gdb.guile/scm-lazy-string.exp b/gdb/testsuite/gdb.guile/scm-lazy-string.exp new file mode 100644 index 00000000000..a3ab4419c18 --- /dev/null +++ b/gdb/testsuite/gdb.guile/scm-lazy-string.exp @@ -0,0 +1,82 @@ +# Copyright (C) 2008-2016 Free Software Foundation, Inc. + +# 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 . + +# This file is part of the GDB testsuite. +# It tests the mechanism exposing lazy strings to Guile. + +load_lib gdb-guile.exp + +standard_testfile + +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } { + return +} + +# Skip all tests if Guile scripting is not enabled. +if { [skip_guile_tests] } { continue } + +#gdb_install_guile_utils +#gdb_install_guile_module + +# The following tests require execution. + +if ![gdb_guile_runto_main] { + fail "Can't run to main" + return +} + +gdb_breakpoint [gdb_get_line_number "break here"] +gdb_continue_to_breakpoint "break here" + +gdb_scm_test_silent_cmd "gu (define null (parse-and-eval \"null\"))" 1 + +gdb_scm_test_silent_cmd "gu (define nullstr (value->lazy-string null #:length 0))" "create a null lazy string" 1 +gdb_test "gu (print (lazy-string-length nullstr))" "= 0" "null lazy string length" +gdb_test "gu (print (lazy-string-address nullstr))" "= 0" "null lazy string address" +gdb_test "gu (print (lazy-string-type nullstr))" "const char \\*" "null lazy string type" +gdb_test "gu (print (lazy-string->value nullstr))" \ + "Out of range: cannot create a value from NULL.*Error while executing Scheme code." \ + "create value from NULL" +gdb_test "gu (print (lazy-string->value (value->lazy-string null #:length 3)))" \ + "Out of range: cannot create a lazy string with address 0x0, and a non-zero length.*Error while executing Scheme code." \ + "null lazy string with non-zero length" +gdb_test "gu (print (value->lazy-string null #:length -2))" \ + "Out of range: invalid length.*Error while executing Scheme code." \ + "bad length" + +foreach var_spec { { "ptr" "pointer" "const char \\*" -1 } \ + { "array" "array" "const char \\[6\\]" 6 } \ + { "typedef_ptr" "typedef pointer" "pointer" -1 } } { + set var [lindex $var_spec 0] + set value [lindex $var_spec 1] + set type [lindex $var_spec 2] + set length [lindex $var_spec 3] + with_test_prefix $var { + gdb_test "print $var" "\"$value\"" + gdb_scm_test_silent_cmd "gu (define $var (history-ref 0))" "get value from history" 1 + gdb_scm_test_silent_cmd "gu (define l$var (value->lazy-string $var))" "acquire lazy string" 1 + gdb_test "gu (print (value-type $var))" "$type" "string type name equality" + gdb_test "gu (print (lazy-string-type l$var))" "$type" "lazy-string type name equality" + gdb_test "gu (print (lazy-string-length l$var))" "$length" "lazy string length" + gdb_test "gu (print (lazy-string->value l$var))" "\"$value\"" "lazy string value" + gdb_scm_test_silent_cmd "gu (define l2$var (value->lazy-string $var #:length 2))" "acquire lazy string, length 2" 1 + gdb_test "gu (print (lazy-string-length l2$var))" "2" "lazy string length 2" + gdb_test "gu (print (lazy-string->value l2$var))" "\"[string range $value 0 1]\"" "lazy string length 2 value" + # This test will have to wait until gdb can handle it. There's no way, + # currently, to internally specify an array of length zero in the C + # language support. PR 20786 + #gdb_test "gu (print (lazy-string->value (value->lazy-string $var #:length 0)))" "\"\"" "empty lazy string value" + } +} diff --git a/gdb/testsuite/gdb.guile/scm-value.c b/gdb/testsuite/gdb.guile/scm-value.c index d4fd369185c..80385c7a2c2 100644 --- a/gdb/testsuite/gdb.guile/scm-value.c +++ b/gdb/testsuite/gdb.guile/scm-value.c @@ -81,13 +81,11 @@ main (int argc, char *argv[]) char nullst[17] = "divide\0et\0impera"; void (*fp1) (void) = &func1; int (*fp2) (int, int) = &func2; - const char *sptr = "pointer"; const char *embed = "embedded x\201\202\203\204"; int a[3] = {1,2,3}; int *p = a; int i = 2; int *ptr_i = &i; - const char *sn = 0; s.a = 3; s.b = 5; u.a = 7; diff --git a/gdb/testsuite/gdb.guile/scm-value.exp b/gdb/testsuite/gdb.guile/scm-value.exp index b3c236c6561..2a276124b3c 100644 --- a/gdb/testsuite/gdb.guile/scm-value.exp +++ b/gdb/testsuite/gdb.guile/scm-value.exp @@ -213,36 +213,6 @@ proc test_strings {} { "restore target-charset" } -proc test_lazy_strings {} { - global hex - - gdb_test "print sptr" "\"pointer\"" - gdb_scm_test_silent_cmd "gu (define sptr (history-ref 0))" \ - "lazy strings: get sptr value from history" - - gdb_scm_test_silent_cmd "gu (define lstr (value->lazy-string sptr))" \ - "Aquire lazy string" - gdb_test "gu (print (lazy-string-type lstr))" \ - "= const char \*." "Test lazy-string type name equality" - gdb_test "gu (print (value-type sptr))" \ - "= const char \*." "Test string type name equality" - - # Prevent symbol on address 0x0 being printed. - gdb_test_no_output "set print symbol off" - gdb_test "print sn" "0x0" - - gdb_scm_test_silent_cmd "gu (define snptr (history-ref 0))" \ - "lazy strings: get snptr value from history" - gdb_test "gu (define snstr (value->lazy-string snptr #:length 5))" \ - ".*cannot create a lazy string with address.*" "Test lazy string" - gdb_scm_test_silent_cmd "gu (define snstr (value->lazy-string snptr #:length 0))" \ - "Successfully create a lazy string" - gdb_test "gu (print (lazy-string-length snstr))" \ - "= 0" "Test lazy string length" - gdb_test "gu (print (lazy-string-address snstr))" \ - "= 0" "Test lazy string address" -} - proc test_inferior_function_call {} { global gdb_prompt hex decimal @@ -457,7 +427,6 @@ if ![gdb_guile_runto_main] { test_value_in_inferior test_inferior_function_call test_strings -test_lazy_strings test_value_after_death # Test either C or C++ values. -- 2.30.2