On Tue, Oct 15, 2024 at 12:36:59PM +0200, Vitezslav Crhonek wrote:
> Hi,
>
> Please review proposed fixes of issues found by static analysis
> of texinfo-7.1 in the attached patch and consider applying them.
>
> During the investigation I stumbled on this chunk of code
> in install-info.c (starting by line 831):
>
> if (fclose (f) < 0)
> return 0;
> f2 = freopen (*opened_filename, FOPEN_RBIN, stdin);
> ---> if (!f)
> return 0;
> f = popen (command, "r");
> fclose (f2);
> if (!f)
> {
> /* Used for error message in calling code. */
> *opened_filename = command;
> return 0;
> }
>
> The marked line seems suspicious - I guess there's a typo and 'f2'
> should be tested instead of 'f' in the condition.
> But this is _not_ changed in proposed patch, just a heads-up here.
I found the code was changed after commit 8f29de69092a.
(2023-10-08 16:54:39 +0100).
It was the change sent in this email:
https://lists.gnu.org/archive/html/bug-texinfo/2023-10/msg00011.html
2023-10-08 Eli Zaretskii <[email protected]>
* install-info/install-info.c (open_possibly_compressed_file):
Close stdin file description in main process after calling popen
on compression program. This allows the file to be removed or
renamed on Windows.
--- a/install-info/install-info.c
+++ b/install-info/install-info.c
@@ -826,13 +826,15 @@ determine_file_type:
/* Redirect stdin to the file and fork the decompression process
reading from stdin. This allows shell metacharacters in filenames. */
char *command = concat (*compression_program, " -d", "");
+ FILE *f2;
if (fclose (f) < 0)
return 0;
- f = freopen (*opened_filename, FOPEN_RBIN, stdin);
+ f2 = freopen (*opened_filename, FOPEN_RBIN, stdin);
if (!f)
return 0;
f = popen (command, "r");
+ fclose (f2);
if (!f)
{
/* Used for error message in calling code. */
It looks like an oversight. f2 is in fact the same as stdin if freopen
is successful. Hence we can eliminate the f2 variable and simplify the
code slightly:
diff --git a/install-info/install-info.c b/install-info/install-info.c
index 9cd909434f..adbe461442 100644
--- a/install-info/install-info.c
+++ b/install-info/install-info.c
@@ -826,15 +826,13 @@ determine_file_type:
/* Redirect stdin to the file and fork the decompression process
reading from stdin. This allows shell metacharacters in filenames. */
char *command = concat (*compression_program, " -d", "");
- FILE *f2;
if (fclose (f) < 0)
return 0;
- f2 = freopen (*opened_filename, FOPEN_RBIN, stdin);
- if (!f)
+ if (!freopen (*opened_filename, FOPEN_RBIN, stdin))
return 0;
f = popen (command, "r");
- fclose (f2);
+ fclose (stdin);
if (!f)
{
/* Used for error message in calling code. */
