Remove unnecessary checks before calls of the function “free”
Hello,
The function “free” is documented in the way that no action shall occur for
a passed null pointer. It is therefore not needed that a function caller
repeats a corresponding check.
https://stackoverflow.com/questions/18775608/free-a-null-pointer-anyway-or-check-first
This issue can be fixed also by using the software “Coccinelle 1.1.1”.
Regards,
Markus
diff --git a/bashline.c b/bashline.c
index c85b05b6..81010b68 100644
--- a/bashline.c
+++ b/bashline.c
@@ -1670,8 +1670,7 @@ attempt_shell_completion (text, start, end)
char *n;
/* XXX - don't free the members */
- if (prog_complete_matches)
- free (prog_complete_matches);
+ free (prog_complete_matches);
prog_complete_matches = (char **)NULL;
os = start;
@@ -1991,8 +1990,7 @@ command_word_completion_function (hint_text, state)
if (dequoted_hint && dequoted_hint != hint)
free (dequoted_hint);
- if (hint)
- free (hint);
+ free (hint);
mapping_over = searching_path = 0;
hint_is_dir = CMD_IS_DIR (hint_text);
@@ -2056,8 +2054,7 @@ command_word_completion_function (hint_text, state)
}
hint_len = strlen (hint);
- if (filename_hint)
- free (filename_hint);
+ free (filename_hint);
fnhint = filename_hint = savestring (hint);
@@ -2093,14 +2090,12 @@ command_word_completion_function (hint_text, state)
/* Initialize the variables for each type of command word. */
local_index = 0;
- if (varlist)
- free (varlist);
+ free (varlist);
varlist = all_visible_functions ();
#if defined (ALIAS)
- if (alias_list)
- free (alias_list);
+ free (alias_list);
alias_list = all_aliases ();
#endif /* ALIAS */
@@ -2273,8 +2268,7 @@ globword:
if (fnhint && fnhint != filename_hint)
free (fnhint);
- if (filename_hint)
- free (filename_hint);
+ free (filename_hint);
filename_hint = sh_makepath (current_path, hint, 0);
/* Need a quoted version (though it doesn't matter much in most
@@ -2409,8 +2403,7 @@ command_subst_completion_function (text, state)
if (state == 0)
{
- if (filename_text)
- free (filename_text);
+ free (filename_text);
orig_start = text;
if (*text == '`')
text++;
@@ -2421,8 +2414,7 @@ command_subst_completion_function (text, state)
rl_completion_suppress_quote = 1;
start_len = text - orig_start;
filename_text = savestring (text);
- if (matches)
- free (matches);
+ free (matches);
/*
* At this point we can entertain the idea of re-parsing
@@ -2491,8 +2483,7 @@ variable_completion_function (text, state)
if (!state)
{
- if (varname)
- free (varname);
+ free (varname);
first_char_loc = 0;
first_char = text[0];
diff --git a/builtins/common.c b/builtins/common.c
index 19b00c4d..b047c44d 100644
--- a/builtins/common.c
+++ b/builtins/common.c
@@ -434,8 +434,7 @@ shift_args (times)
while (times-- > 0)
{
- if (dollar_vars[1])
- free (dollar_vars[1]);
+ free (dollar_vars[1]);
for (count = 1; count < 9; count++)
dollar_vars[count] = dollar_vars[count + 1];
diff --git a/builtins/mkbuiltins.c b/builtins/mkbuiltins.c
index f505ebde..350d8bbd 100644
--- a/builtins/mkbuiltins.c
+++ b/builtins/mkbuiltins.c
@@ -261,8 +261,7 @@ main (argc, argv)
{
int len;
- if (error_directory)
- free (error_directory);
+ free (error_directory);
error_directory = xmalloc (2 + strlen (argv[arg_index]));
strcpy (error_directory, argv[arg_index]);
@@ -448,9 +447,7 @@ void
array_free (array)
ARRAY *array;
{
- if (array->array)
-free (array->array);
-
+ free (array->array);
free (array);
}
@@ -695,8 +692,7 @@ free_defs (defs)
register int i;
register BUILTIN_DESC *builtin;
- if (defs->production)
-free (defs->production);
+ free (defs->production);
if (defs->lines)
array_free (defs->lines);
diff --git a/examples/loadables/csv.c b/examples/loadables/csv.c
index 75b37725..de7564a2 100644
--- a/examples/loadables/csv.c
+++ b/examples/loadables/csv.c
@@ -96,8 +96,7 @@ csvsplit (csv, line, dstring)
}
while (delim == *dstring);
- if (xbuf)
-free (xbuf);
+ free (xbuf);
return (rval = ind);/* number of fields */
}
diff --git a/examples/loadables/dsv.c b/examples/loadables/dsv.c
index 70e59cbc..187ef685 100644
--- a/examples/loadables/dsv.c
+++ b/examples/loadables/dsv.c
@@ -156,8 +156,7 @@ dsvsplit (dsv, line, dstring, flags)
}
while (delim == *dstring);
- if (xbuf)
-free (xbuf);
+ free (xbuf);
return (rval = ind);/* number of fields */
}
diff --git a/execute_cmd.c b/execute_cmd.c
index e5c6b9ab..b3b0aa31 100644
--- a/execute_cmd.c
+++ b/execute_cmd.c
@@ -5527,8 +5527,7 @@ execute_builtin_or_function (words, builtin, var, redirects,
nfifo = num_fifos ();
if (nfifo > ofifo)
close_new_fifos (ofifo_list, osize);
- if (ofifo_list)
-free
Checking evolution of information about required symbols
Hello, Some information was published with the subject “Bash-5.2 Release available” on 2022-09-26. https://lists.gnu.org/archive/html/bug-bash/2022-09/msg00056.html https://www.mail-archive.com/info-gnu@gnu.org/msg03096.html “… Bash can be linked against an already-installed Readline library rather than the private version in lib/readline if desired. Only readline-8.1 and later versions are able to provide all of the symbols that bash-5.2 requires; …” Would you like to recheck and reconsider such information in more detail? On how many symbols does this program revision depend? I got the impression that some of them became generally available only with the change “readline-8.2 distribution sources and documentation” on 2022-09-26. https://git.savannah.gnu.org/cgit/readline.git/commit/readline.h?id=f7a382fd09319b20ef4435b9b554183b605468c1 https://lists.gnu.org/archive/html/bug-readline/2022-09/msg00010.html https://www.mail-archive.com/info-gnu@gnu.org/msg03097.html How do you think about related searches for appropriate solutions? Examples: * 2022-10-02 shells/bash: bash-5.2_2 is marked as broken: ld: error: undefined symbol: rl_trim_arg_from_keyseq https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=266762 * 2022-10-15 Fix the availability of the symbol “rl_trim_arg_from_keyseq” (for “bash 5.2.2”) https://bugzilla.opensuse.org/show_bug.cgi?id=1204336 * 2022-10-18 Checking ABI adjustments once more https://lists.gnu.org/archive/html/bug-readline/2022-10/msg00017.html Regards, Markus
Re: Checking executability for asynchronous commands
>…, is not a winning argument. I got further development ideas according to the usage of wait function calls and better error reporting for asynchronous commands. >The OP seems to think that "people will occasionally forget to run `wait`", This happens for various reasons. > and wants to know if we "care" that people will forget … The attention varies for this implementation aspect. > Why should we care? Would you like to care for proper management of system resources (including process identifications)? >The official advice is to run `wait` How do you think about any additional guidance for such a programming interface? Regards, Markus
Re: Checking executability for asynchronous commands
>> Would you care if waiting on such identifications for background processes >> will occasionally be forgotten? >> >> How many efforts would you invest to add potentially missing wait function >> calls? > > It's axiomatic: if you want to make a decision based on the exit status of > any asynchronous process, you need to use `wait' to obtain the status of > that process. > > I don't think "I don't want to do it that way" is a good reason to provide > a different method. I got another programming concern: Process identifications are a system resource. The exit status is preserved until this information will eventually be used for corresponding data processing. How many processes can a selected system configuration handle? Regards, Markus
Re: Checking executability for asynchronous commands
> If you have the pid of an asynchronous command -- and the easiest way to get > that pid > is by referencing $! after it was started -- you can call `wait' with that pid > to retrieve the status, even if it's already terminated. Would you care if waiting on such identifications for background processes will occasionally be forgotten? How many efforts would you invest to add potentially missing wait function calls? Regards, Markus
Re: Checking executability for asynchronous commands
> If you want the exit status of the child process, add `wait $!' Thanks for this information. Is there a need then to point the aspect out that exit values can be determined for child processes even if they terminated before a wait command would be performed? Regards, Markus
Re: Checking executability for asynchronous commands
> Are you maybe saying > > cmd & > > should be a special case? I got special imaginations according to such a command variant. Regards, Markus
Checking executability for asynchronous commands
Hello, I am looking for another bit of clarification according to an implementation detail. The manual is providing the following information. https://git.savannah.gnu.org/cgit/bash.git/tree/doc/bash.1?id=76404c85d492c001f59f2644074333ffb7608532#n627 “… If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0. …” Thus I observe a behaviour like the following for a simple test with the software “bash 5.0.18-3.1” according to a “program” which does not exist here. elfring@Sonne:~> xy & [1] 4063 xy: Befehl nicht gefunden [1]+ Exit 127xy I imagine that it can be occasionally helpful to determine the execution failure in the synchronous way. Would it make sense to configure the error reporting for selected asynchronous commands so that they would become background processes only after the required check for executability? Regards, Markus
Re: Bash-4.3-beta2: reserved identifier violation
ftp://ftp.cwru.edu/pub/bash/bash-4.3-beta2.tar.gz Hello, I would like to point out that identifiers like _ARRAY_H_ and _PARSER_H_ do not fit to the expected naming convention of the C language standard. https://www.securecoding.cert.org/confluence/display/seccode/DCL37-C.+Do+not+declare+or+define+a+reserved+identifier#DCL37-C.Donotdeclareordefineareservedidentifier-NoncompliantCodeExample%28HeaderGuard%29 Would you like to adjust your selection for unique names? Regards, Markus
