[PR,symtab/17911] Recognize bad file types
Commit Message
Pedro Alves <palves@redhat.com> writes:
> On 09/19/2015 11:40 PM, Doug Evans wrote:
>
>> diff --git a/gdb/source.c b/gdb/source.c
>> index fab974c..34384fa 100644
>> --- a/gdb/source.c
>> +++ b/gdb/source.c
>> @@ -684,7 +684,10 @@ source_info (char *ignore, int from_tty)
>> }
>>
>>
>> -/* Return True if the file NAME exists and is a regular file. */
>> +/* Return True if the file NAME exists and is a regular file.
>> + If the result is false then errno is set to a useful value assuming we're
>> + expecting a regular file. */
>> +
>> static int
>> is_regular_file (const char *name)
>> {
>> @@ -699,7 +702,14 @@ is_regular_file (const char *name)
>> if (status != 0)
>> return (errno != ENOENT);
>>
>> - return S_ISREG (st.st_mode);
>> + if (S_ISREG (st.st_mode))
>> + return 1;
>> +
>> + if (S_ISDIR (st.st_mode))
>> + errno = EISDIR;
>> + else
>> + errno = EINVAL;
>> + return 0;
>> }
>>
>> /* Open a file named STRING, searching path PATH (dir names sep by some char)
>> @@ -785,6 +795,7 @@ openp (const char *path, int opts, const char *string,
>> {
>> filename = NULL;
>> fd = -1;
>> + /* Note: is_regular_file will have set errno appropriately. */
>> }
>>
>> if (!(opts & OPF_SEARCH_IN_PATH))
>> @@ -808,6 +819,7 @@ openp (const char *path, int opts, const char *string,
>> alloclen = strlen (path) + strlen (string) + 2;
>> filename = alloca (alloclen);
>> fd = -1;
>> + errno = ENOENT;
>>
>> dir_vec = dirnames_to_char_ptr_vec (path);
>> back_to = make_cleanup_free_char_ptr_vec (dir_vec);
>> @@ -879,6 +891,10 @@ openp (const char *path, int opts, const char *string,
>> if (fd >= 0)
>> break;
>> }
>> + else
>> + {
>> + /* Note: is_regular_file will have set errno appropriately. */
>> + }
>> }
>
> Seems like there are function calls after these that may
> clobber errno. I think it'd be safer to do the usual
> save_errno = errno; / errno = save_errno; dance.
>
>> +# Test passing bad files to gdb. PR symtab/17911
>> +
>> +# We watch for specific text for errno, so only test on systems we have
>> +# confidence in the error text.
>> +
>> +if { ! [ishost "*-*-linux*"] } {
>> + return 0
>> +}
>
> Same comment as to the other patch -- I think we should instead
> remove this check and if the error message is different on other
> hosts, then whoever cares about such hosts will adjust the
> test. I don't think there will be that many cases of
> different messages.
>
> Otherwise LGTM.
Here is what I committed.
[This version passes errno back as an argument.]
2016-04-19 Doug Evans <xdje42@gmail.com>
* source.c (is_regular_file): New arg errno_ptr.
All callers updated.
testsuite/
* gdb.base/bad-file.exp: New file.
@@ -685,9 +685,12 @@ source_info (char *ignore, int from_tty)
}
-/* Return True if the file NAME exists and is a regular file. */
+/* Return True if the file NAME exists and is a regular file.
+ If the result is false then *ERRNO_PTR is set to a useful value assuming
+ we're expecting a regular file. */
+
static int
-is_regular_file (const char *name)
+is_regular_file (const char *name, int *errno_ptr)
{
struct stat st;
const int status = stat (name, &st);
@@ -698,9 +701,21 @@ is_regular_file (const char *name)
on obscure systems where stat does not work as expected. */
if (status != 0)
- return (errno != ENOENT);
+ {
+ if (errno != ENOENT)
+ return 1;
+ *errno_ptr = ENOENT;
+ return 0;
+ }
- return S_ISREG (st.st_mode);
+ if (S_ISREG (st.st_mode))
+ return 1;
+
+ if (S_ISDIR (st.st_mode))
+ *errno_ptr = EISDIR;
+ else
+ *errno_ptr = EINVAL;
+ return 0;
}
/* Open a file named STRING, searching path PATH (dir names sep by some char)
@@ -775,22 +790,23 @@ openp (const char *path, int opts, const char *string,
if ((opts & OPF_TRY_CWD_FIRST) || IS_ABSOLUTE_PATH (string))
{
- int i;
+ int i, reg_file_errno;
- if (is_regular_file (string))
+ if (is_regular_file (string, ®_file_errno))
{
filename = (char *) alloca (strlen (string) + 1);
strcpy (filename, string);
fd = gdb_open_cloexec (filename, mode, 0);
if (fd >= 0)
goto done;
+ last_errno = errno;
}
else
{
filename = NULL;
fd = -1;
+ last_errno = reg_file_errno;
}
- last_errno = errno;
if (!(opts & OPF_SEARCH_IN_PATH))
for (i = 0; string[i]; i++)
@@ -821,6 +837,7 @@ openp (const char *path, int opts, const char *string,
for (ix = 0; VEC_iterate (char_ptr, dir_vec, ix, dir); ++ix)
{
size_t len = strlen (dir);
+ int reg_file_errno;
if (strcmp (dir, "$cwd") == 0)
{
@@ -879,13 +896,15 @@ openp (const char *path, int opts, const char *string,
strcat (filename + len, SLASH_STRING);
strcat (filename, string);
- if (is_regular_file (filename))
+ if (is_regular_file (filename, ®_file_errno))
{
fd = gdb_open_cloexec (filename, mode, 0);
if (fd >= 0)
break;
last_errno = errno;
}
+ else
+ last_errno = reg_file_errno;
}
do_cleanups (back_to);
new file mode 100644
@@ -0,0 +1,54 @@
+# Copyright 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 <http://www.gnu.org/licenses/>. */
+
+# Test passing bad files to gdb. PR symtab/17911
+
+# Note: While we test for specific text in error messages,
+# thus perhaps making the test host specific, if your host
+# print different text then the plan is to update the expected text
+# instead of making this test linux-only or some such.
+
+# There is no such file, but we still use the normal mechanism to pick
+# its name and path.
+standard_testfile
+
+gdb_exit
+gdb_start
+
+set test "non-existent file"
+set bad_file $testfile
+remote_file host delete $bad_file
+gdb_test_multiple "file $bad_file" "$test" {
+ -re "No such file or directory.\[\r\n\]+$gdb_prompt $" {
+ pass $test
+ }
+}
+
+set test "directory"
+set bad_file [standard_output_file {}]
+remote_exec host "mkdir -p $bad_file"
+gdb_test_multiple "file $bad_file" "$test" {
+ -re "Is a directory.\[\r\n\]+$gdb_prompt $" {
+ pass $test
+ }
+}
+
+set test "neither file nor directory"
+set bad_file "/dev/null"
+gdb_test_multiple "file $bad_file" "$test" {
+ -re "Invalid argument.\[\r\n\]+$gdb_prompt $" {
+ pass $test
+ }
+}