On Mon, Jul 01, 2024 at 06:56:21PM +0200, Michal Sekletar wrote:
[...]
> --- a/libdwfl/link_map.c
> +++ b/libdwfl/link_map.c
> @@ -416,8 +416,22 @@ report_r_debug (uint_fast8_t elfclass, uint_fast8_t
> elfdata,
> if (name != NULL)
> {
> /* This code is mostly inlined dwfl_report_elf. */
> - // XXX hook for sysroot
> - int fd = open (name, O_RDONLY);
> + int rc;
> + char *path_name;
> + const char *sysroot = dwfl->sysroot;
> +
> + /* Don't use the sysroot if the path is already inside it. */
> + bool name_in_sysroot = sysroot && (strncmp(name, sysroot,
> strlen(sysroot)) == 0);
This seems to be a good candidate for startswith(), e.g.
bool name_in_sysroot = sysroot && startswith(name, sysroot);
Is sysroot guaranteed to end with '/'? If not, then sysroot being
a prefix doesn't always imply that the path is inside sysroot.
> +
> + if (!name_in_sysroot && sysroot)
> + rc = asprintf(&path_name, "%s/%s", sysroot, name);
> + else
> + rc = asprintf(&path_name, "%s", name);
Do we need the last asprintf(), or could we use "name" directly?
In fact, besides this open(), "name" is used later in this function as an
argument to __libdwfl_report_elf(). Does that invocation also has to be
updated?
Could "name" be re-purposed a bit in case of sysroot? Just an idea,
completely untested:
char *sysroot_name = NULL;
...
if (sysroot && !name_in_sysroot)
{
if (asprintf(&sysroot_name, "%s/%s", sysroot, name) < 0)
return ...;
name = sysroot_name;
}
...
free(sysroot_name);
--
ldv
