[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [warnings 3/7] Suppress warnings about conversions between char * an
|
From: |
John Darrington |
|
Subject: |
Re: [warnings 3/7] Suppress warnings about conversions between char * and unsigned char *. |
|
Date: |
Sat, 18 Sep 2010 06:56:47 +0000 |
|
User-agent: |
Mutt/1.5.18 (2008-05-17) |
Many of these problems are caused by the disire to use the libpspp/str.h
functions
for a uint8_t array. If we had a similiar module for unsigned strings, then a
lot
of these casts could be avoided. Oh for C++ templates!!
On Fri, Sep 17, 2010 at 09:36:28PM -0700, Ben Pfaff wrote:
For some time PSPP has used "unsigned char *" for string data and "Char *"
for most other strings. Transforming between these properly generally
involves recoding, and there are some places where this is possibly
missing. The usual way to "fix" these warnings would be to insert casts,
but this would not fix the problem, just suppress the warnings, and it is
difficult to "grep" for casts so they would be hard to find for fixing
later.
This commit doesn't actually fix the problems, but it does suppress the
warnings while making them easy to find later: just grep for CHAR_CAST_BUG.
---
src/language/expressions/operations.def | 9 ++++++---
src/language/lexer/value-parser.c | 27 ++++++++++++++++-----------
src/language/xforms/compute.c | 12 +++++++-----
src/language/xforms/recode.c | 10 ++++++----
src/libpspp/cast.h | 25 ++++++++++++++++++++++++-
src/ui/syntax-gen.c | 22 +++++++++++++---------
6 files changed, 72 insertions(+), 33 deletions(-)
diff --git a/src/language/expressions/operations.def
b/src/language/expressions/operations.def
index 844cab7..c25f113 100644
--- a/src/language/expressions/operations.def
+++ b/src/language/expressions/operations.def
@@ -961,7 +961,8 @@ absorb_miss no_opt string operator VEC_ELEM_STR (idx)
if (idx >= 1 && idx <= vector_get_var_cnt (v))
{
struct variable *var = vector_get_var (v, (size_t) idx - 1);
- return copy_string (e, case_str (c, var), var_get_width (var));
+ return copy_string (e, CHAR_CAST_BUG (char *, case_str (c, var)),
+ var_get_width (var));
}
else
{
@@ -1029,7 +1030,8 @@ no_opt perm_only string function LAG (str_var v,
pos_int n_before)
{
const struct ccase *c = lagged_case (ds, n_before);
if (c != NULL)
- return copy_string (e, case_str (c, v), var_get_width (v));
+ return copy_string (e, CHAR_CAST_BUG (char *, case_str (c, v)),
+ var_get_width (v));
else
return empty_string;
}
@@ -1040,7 +1042,8 @@ no_opt perm_only string function LAG (str_var v)
{
const struct ccase *c = lagged_case (ds, 1);
if (c != NULL)
- return copy_string (e, case_str (c, v), var_get_width (v));
+ return copy_string (e, CHAR_CAST_BUG (char *, case_str (c, v)),
+ var_get_width (v));
else
return empty_string;
}
diff --git a/src/language/lexer/value-parser.c
b/src/language/lexer/value-parser.c
index c780d86..c492658 100644
--- a/src/language/lexer/value-parser.c
+++ b/src/language/lexer/value-parser.c
@@ -1,5 +1,5 @@
/* PSPP - a program for statistical analysis.
- Copyright (C) 2005, 2006, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006, 2009, 2010 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
@@ -15,14 +15,18 @@
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
+
#include "value-parser.h"
+
#include <stdbool.h>
-#include <data/data-in.h>
-#include <libpspp/message.h>
-#include "lexer.h"
-#include <libpspp/str.h>
-#include <data/value.h>
-#include <data/format.h>
+
+#include "data/data-in.h"
+#include "data/format.h"
+#include "data/value.h"
+#include "language/lexer/lexer.h"
+#include "libpspp/cast.h"
+#include "libpspp/message.h"
+#include "libpspp/str.h"
#include "gettext.h"
#define _(msgid) gettext (msgid)
@@ -133,12 +137,13 @@ parse_value (struct lexer *lexer, union value *v,
int width)
return false;
v->f = lex_tokval (lexer);
}
- else
+ else if (lex_force_string (lexer))
{
- if (!lex_force_string (lexer))
- return false;
- value_copy_str_rpad (v, width, ds_cstr (lex_tokstr (lexer)), ' ');
+ const char *s = ds_cstr (lex_tokstr (lexer));
+ value_copy_str_rpad (v, width, CHAR_CAST_BUG (const uint8_t *, s),
' ');
}
+ else
+ return false;
lex_get (lexer);
diff --git a/src/language/xforms/compute.c b/src/language/xforms/compute.c
index 09fc215..a508933 100644
--- a/src/language/xforms/compute.c
+++ b/src/language/xforms/compute.c
@@ -1,5 +1,5 @@
/* PSPP - a program for statistical analysis.
- Copyright (C) 1997-9, 2000, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1997-9, 2000, 2009, 2010 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
@@ -173,10 +173,11 @@ compute_str (void *compute_, struct ccase **c,
casenumber case_num)
if (compute->test == NULL
|| expr_evaluate_num (compute->test, *c, case_num) == 1.0)
{
+ char *s;
+
*c = case_unshare (*c);
- expr_evaluate_str (compute->rvalue, *c, case_num,
- case_str_rw (*c, compute->variable),
- compute->width);
+ s = CHAR_CAST_BUG (char *, case_str_rw (*c, compute->variable));
+ expr_evaluate_str (compute->rvalue, *c, case_num, s,
compute->width);
}
return TRNS_CONTINUE;
@@ -216,7 +217,8 @@ compute_str_vec (void *compute_, struct ccase **c,
casenumber case_num)
vr = vector_get_var (compute->vector, rindx - 1);
*c = case_unshare (*c);
expr_evaluate_str (compute->rvalue, *c, case_num,
- case_str_rw (*c, vr), var_get_width (vr));
+ CHAR_CAST_BUG (char *, case_str_rw (*c, vr)),
+ var_get_width (vr));
}
return TRNS_CONTINUE;
diff --git a/src/language/xforms/recode.c b/src/language/xforms/recode.c
index 424e0af..fff74f7 100644
--- a/src/language/xforms/recode.c
+++ b/src/language/xforms/recode.c
@@ -1,5 +1,5 @@
/* PSPP - a program for statistical analysis.
- Copyright (C) 1997-9, 2000, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1997-9, 2000, 2009, 2010 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
@@ -373,7 +373,8 @@ set_map_in_str (struct map_in *in, struct pool *pool,
in->type = MAP_SINGLE;
value_init_pool (pool, &in->x, width);
value_copy_buf_rpad (&in->x, width,
- ds_data (string), ds_length (string), ' ');
+ CHAR_CAST_BUG (uint8_t *, ds_data (string)),
+ ds_length (string), ' ');
}
/* Parses a mapping output value into OUT, allocating memory from
@@ -629,8 +630,9 @@ find_src_string (struct recode_trns *trns, const
uint8_t *value,
union value uv;
msg_disable ();
- match = data_in (ss_buffer (value, width), LEGACY_NATIVE,
- FMT_F, 0, 0, 0, trns->dst_dict, &uv, 0);
+ match = data_in (ss_buffer (CHAR_CAST_BUG (char *, value),
width),
+ LEGACY_NATIVE, FMT_F, 0, 0, 0,
trns->dst_dict,
+ &uv, 0);
msg_enable ();
out->value.f = uv.f;
break;
diff --git a/src/libpspp/cast.h b/src/libpspp/cast.h
index 1e33857..5c64fac 100644
--- a/src/libpspp/cast.h
+++ b/src/libpspp/cast.h
@@ -1,5 +1,5 @@
/* PSPP - a program for statistical analysis.
- Copyright (C) 2009 Free Software Foundation, Inc.
+ Copyright (C) 2009, 2010 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
@@ -18,6 +18,7 @@
#define LIBPSPP_CAST_H 1
#include <stddef.h>
+#include "gl/verify.h"
/* Expands to a void expression that checks that POINTER is an
expression whose type is a qualified or unqualified version of
@@ -83,6 +84,28 @@
(CHECK_POINTER_HAS_TYPE (POINTER, TYPE), \
(TYPE) (POINTER))
+/* Casts POINTER to TYPE. Yields a compiler diagnostic if either TYPE or
+ POINTER is not a pointer to character type.
+
+ PSPP uses "unsigned char" (actually uint8_t) in "union value" and
"char"
+ elsewhere to emphasize that data in union value usually requires
reencoding
+ when transferred to and from other string types. These macros
suppress the
+ warning when implicitly converting between pointers to different
character
+ types, so their use normally marks a bug that should eventually be
fixed.
+ However, until these bugs are fixed, suppressing the warnings is much
less
+ annoying.
+
+ Use CHAR_CAST_BUG if you think there is a bug to be fixed, or if you
have
+ not yet carefully examined the situation, or if you are not sure.
+ Use CHAR_CAST if you are convinced that this is actually a correct
cast. */
+#define CHAR_CAST(TYPE, POINTER) \
+ ((void) verify_true (sizeof (*(POINTER)) == 1), \
+ (void) (sizeof (*(POINTER) + 1)), \
+ (void) verify_true (sizeof (*(TYPE) NULL) == 1), \
+ (void) (sizeof (*(TYPE) NULL + 1)), \
+ (TYPE) (POINTER))
+#define CHAR_CAST_BUG(TYPE, POINTER) CHAR_CAST(TYPE, POINTER)
+
/* Given POINTER, a pointer to the given MEMBER within structure
STRUCT, returns the address of the STRUCT. */
#define UP_CAST(POINTER, STRUCT, MEMBER) \
diff --git a/src/ui/syntax-gen.c b/src/ui/syntax-gen.c
index 22e717a..229e478 100644
--- a/src/ui/syntax-gen.c
+++ b/src/ui/syntax-gen.c
@@ -1,5 +1,5 @@
/* PSPPIRE - a graphical user interface for PSPP.
- Copyright (C) 2008 Free Software Foundation, Inc.
+ Copyright (C) 2008, 2010 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
@@ -21,13 +21,14 @@
#include <ctype.h>
#include <mbchar.h>
-#include <data/data-in.h>
-#include <data/data-out.h>
-#include <data/format.h>
-#include <data/value.h>
-#include <libpspp/assertion.h>
-#include <libpspp/message.h>
-#include <libpspp/str.h>
+#include "data/data-in.h"
+#include "data/data-out.h"
+#include "data/format.h"
+#include "data/value.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "libpspp/message.h"
+#include "libpspp/str.h"
/* Appends to OUTPUT a pair of hex digits for each byte in IN. */
static void
@@ -197,7 +198,10 @@ syntax_gen_value (struct string *output, const union
value *value, int width,
if (width == 0)
syntax_gen_number (output, value->f, format);
else
- syntax_gen_string (output, ss_buffer (value_str (value, width),
width));
+ {
+ char *s = CHAR_CAST_BUG (char *, value_str (value, width));
+ syntax_gen_string (output, ss_buffer (s, width));
+ }
}
/* Appends <low> THRU <high> to OUTPUT. If LOW is LOWEST, then
--
1.7.1
_______________________________________________
pspp-dev mailing list
address@hidden
http://lists.gnu.org/mailman/listinfo/pspp-dev
--
PGP Public key ID: 1024D/2DE827B3
fingerprint = 8797 A26D 0854 2EAB 0285 A290 8A67 719C 2DE8 27B3
See http://pgp.mit.edu or any PGP keyserver for public key.
signature.asc
Description: Digital signature
- [warnings 6/7] linreg: Delete unused static function., (continued)
- [warnings 6/7] linreg: Delete unused static function., Ben Pfaff, 2010/09/18
- [warnings 7/7] GLM: Fix compiler warnings., Ben Pfaff, 2010/09/18
- [warnings 1/7] build-aux: Add generated files to .gitignore., Ben Pfaff, 2010/09/18
- [warnings 3/7] Suppress warnings about conversions between char * and unsigned char *., Ben Pfaff, 2010/09/18
- [warnings 5/7] Fix some constness problems that led to warnings., Ben Pfaff, 2010/09/18
- [warnings 2/7] recode: Fix a warning in recode_trns_proc()., Ben Pfaff, 2010/09/18