[PATCH] nss: Clean up function pointer/void * unions
Adhemerval Zanella Netto
adhemerval.zanella@linaro.org
Mon Nov 17 18:54:10 GMT 2025
On 17/11/25 13:18, Florian Weimer wrote:
> All our targets support casts between function pointers and void *,
> so we might as well use them.
>
> This change was largely-autogenerated, with the following prompts.
>
> @getXXbyYY_r.c Remove the use of the `fct` union and replace it by
> pointer casts.
>
> Apply the same change to ether_* getnetgrent_r getnssent_r netname
> publickey .
>
> Do not use explicit `*` in function pointer calls. Replace
> `(*((lookup_function) fct))` and similar with `((lookup_function) fct)`.
LGTM, thanks.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
>
> ---
> nss/ether_hton.c | 13 +++++--------
> nss/ether_ntoh.c | 13 +++++--------
> nss/getXXbyYY_r.c | 15 ++++++---------
> nss/getnetgrent_r.c | 30 +++++++++++++-----------------
> nss/getnssent_r.c | 50 +++++++++++++++++---------------------------------
> sunrpc/netname.c | 13 +++++--------
> sunrpc/publickey.c | 24 ++++++++----------------
> 7 files changed, 59 insertions(+), 99 deletions(-)
>
> diff --git a/nss/ether_hton.c b/nss/ether_hton.c
> index 588828cc1e..3c5b25c537 100644
> --- a/nss/ether_hton.c
> +++ b/nss/ether_hton.c
> @@ -30,24 +30,21 @@ int
> ether_hostton (const char *hostname, struct ether_addr *addr)
> {
> nss_action_list nip;
> - union
> - {
> - lookup_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> struct etherent etherent;
>
> - no_more = __nss_ethers_lookup2 (&nip, "gethostton_r", NULL, &fct.ptr);
> + no_more = __nss_ethers_lookup2 (&nip, "gethostton_r", NULL, &fct);
>
> while (no_more == 0)
> {
> char buffer[1024];
>
> - status = (*fct.f) (hostname, ðerent, buffer, sizeof buffer, &errno);
> + status = ((lookup_function) fct) (hostname, ðerent, buffer,
> + sizeof buffer, &errno);
>
> - no_more = __nss_next2 (&nip, "gethostton_r", NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (&nip, "gethostton_r", NULL, &fct, status, 0);
> }
>
> if (status == NSS_STATUS_SUCCESS)
> diff --git a/nss/ether_ntoh.c b/nss/ether_ntoh.c
> index 2185b9e386..207a3103f0 100644
> --- a/nss/ether_ntoh.c
> +++ b/nss/ether_ntoh.c
> @@ -31,24 +31,21 @@ int
> ether_ntohost (char *hostname, const struct ether_addr *addr)
> {
> nss_action_list nip;
> - union
> - {
> - lookup_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> struct etherent etherent;
>
> - no_more = __nss_ethers_lookup2 (&nip, "getntohost_r", NULL, &fct.ptr);
> + no_more = __nss_ethers_lookup2 (&nip, "getntohost_r", NULL, &fct);
>
> while (no_more == 0)
> {
> char buffer[1024];
>
> - status = (*fct.f) (addr, ðerent, buffer, sizeof buffer, &errno);
> + status = ((lookup_function) fct) (addr, ðerent, buffer,
> + sizeof buffer, &errno);
>
> - no_more = __nss_next2 (&nip, "getntohost_r", NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (&nip, "getntohost_r", NULL, &fct, status, 0);
> }
>
> if (status == NSS_STATUS_SUCCESS)
> diff --git a/nss/getXXbyYY_r.c b/nss/getXXbyYY_r.c
> index 2b0735fb6a..9f7188ab41 100644
> --- a/nss/getXXbyYY_r.c
> +++ b/nss/getXXbyYY_r.c
> @@ -189,11 +189,7 @@ INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
> LOOKUP_TYPE mergegrp;
> char *mergebuf = NULL;
> char *endptr = NULL;
> - union
> - {
> - lookup_function l;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more, err;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> #ifdef USE_NSCD
> @@ -258,7 +254,7 @@ INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
> #endif
>
> no_more = DB_LOOKUP_FCT (&nip, REENTRANT_NAME_STRING,
> - REENTRANT2_NAME_STRING, &fct.ptr);
> + REENTRANT2_NAME_STRING, &fct);
>
> while (no_more == 0)
> {
> @@ -266,8 +262,9 @@ INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
> any_service = true;
> #endif
>
> - status = DL_CALL_FCT (fct.l, (ADD_VARIABLES, resbuf, buffer, buflen,
> - &errno H_ERRNO_VAR EXTRA_VARIABLES));
> + status = DL_CALL_FCT (((lookup_function) fct),
> + (ADD_VARIABLES, resbuf, buffer, buflen,
> + &errno H_ERRNO_VAR EXTRA_VARIABLES));
>
> /* The status is NSS_STATUS_TRYAGAIN and errno is ERANGE the
> provided buffer is too small. In this case we should give
> @@ -337,7 +334,7 @@ INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
> }
>
> no_more = __nss_next2 (&nip, REENTRANT_NAME_STRING,
> - REENTRANT2_NAME_STRING, &fct.ptr, status, 0);
> + REENTRANT2_NAME_STRING, &fct, status, 0);
> }
> free (mergebuf);
> mergebuf = NULL;
> diff --git a/nss/getnetgrent_r.c b/nss/getnetgrent_r.c
> index f5137ad078..df16cfe150 100644
> --- a/nss/getnetgrent_r.c
> +++ b/nss/getnetgrent_r.c
> @@ -85,11 +85,7 @@ static int
> __internal_setnetgrent_reuse (const char *group, struct __netgrent *datap,
> int *errnop)
> {
> - union
> - {
> - enum nss_status (*f) (const char *, struct __netgrent *);
> - void *ptr;
> - } fct;
> + void *fct;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> struct name_list *new_elem;
>
> @@ -97,16 +93,18 @@ __internal_setnetgrent_reuse (const char *group, struct __netgrent *datap,
> endnetgrent_hook (datap);
>
> /* Cycle through all the services and run their setnetgrent functions. */
> - int no_more = setup (&fct.ptr, &datap->nip);
> + int no_more = setup (&fct, &datap->nip);
> while (! no_more)
> {
> assert (datap->data == NULL);
>
> /* Ignore status, we force check in `__nss_next2'. */
> - status = DL_CALL_FCT (*fct.f, (group, datap));
> + status = DL_CALL_FCT (((enum nss_status (*) (const char *,
> + struct __netgrent *)) fct),
> + (group, datap));
>
> nss_action_list old_nip = datap->nip;
> - no_more = __nss_next2 (&datap->nip, "setnetgrent", NULL, &fct.ptr,
> + no_more = __nss_next2 (&datap->nip, "setnetgrent", NULL, &fct,
> status, 0);
>
> if (status == NSS_STATUS_SUCCESS && ! no_more)
> @@ -372,11 +370,7 @@ innetgr (const char *netgroup, const char *host, const char *user,
> }
> #endif
>
> - union
> - {
> - enum nss_status (*f) (const char *, struct __netgrent *);
> - void *ptr;
> - } setfct;
> + void *setfct;
> void (*endfct) (struct __netgrent *);
> int (*getfct) (struct __netgrent *, char *, size_t, int *);
> struct __netgrent entry;
> @@ -391,14 +385,16 @@ innetgr (const char *netgroup, const char *host, const char *user,
> the work during one walk through the service list. */
> while (1)
> {
> - int no_more = setup (&setfct.ptr, &entry.nip);
> + int no_more = setup (&setfct, &entry.nip);
> while (! no_more)
> {
> assert (entry.data == NULL);
>
> /* Open netgroup. */
> - enum nss_status status = DL_CALL_FCT (*setfct.f,
> - (current_group, &entry));
> + enum nss_status status
> + = DL_CALL_FCT (((enum nss_status (*) (const char *,
> + struct __netgrent *))
> + setfct), (current_group, &entry));
>
> if (status == NSS_STATUS_SUCCESS
> && (getfct = __nss_lookup_function (entry.nip, "getnetgrent_r"))
> @@ -474,7 +470,7 @@ innetgr (const char *netgroup, const char *host, const char *user,
>
> /* Look for the next service. */
> no_more = __nss_next2 (&entry.nip, "setnetgrent", NULL,
> - &setfct.ptr, status, 0);
> + &setfct, status, 0);
> }
>
> if (result == 0 && entry.needed_groups != NULL)
> diff --git a/nss/getnssent_r.c b/nss/getnssent_r.c
> index 56258d5f09..10166f2420 100644
> --- a/nss/getnssent_r.c
> +++ b/nss/getnssent_r.c
> @@ -53,11 +53,7 @@ __nss_setent (const char *func_name, db_lookup_function lookup_fct,
> nss_action_list *last_nip, int stayopen, int *stayopen_tmp,
> int res)
> {
> - union
> - {
> - setent_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more;
>
> struct resolv_context *res_ctx = NULL;
> @@ -73,7 +69,7 @@ __nss_setent (const char *func_name, db_lookup_function lookup_fct,
>
> /* Cycle through the services and run their `setXXent' functions until
> we find an available service. */
> - no_more = setup (func_name, lookup_fct, &fct.ptr, nip,
> + no_more = setup (func_name, lookup_fct, &fct, nip,
> startp, 1);
> while (! no_more)
> {
> @@ -81,9 +77,9 @@ __nss_setent (const char *func_name, db_lookup_function lookup_fct,
> enum nss_status status;
>
> if (stayopen_tmp)
> - status = DL_CALL_FCT (fct.f, (*stayopen_tmp));
> + status = DL_CALL_FCT (((setent_function) fct), (*stayopen_tmp));
> else
> - status = DL_CALL_FCT (fct.f, (0));
> + status = DL_CALL_FCT (((setent_function) fct), (0));
>
>
> /* This is a special-case. When [SUCCESS=merge] is in play,
> @@ -95,7 +91,7 @@ __nss_setent (const char *func_name, db_lookup_function lookup_fct,
> if (nss_next_action (*nip, status) == NSS_ACTION_MERGE)
> no_more = 1;
> else
> - no_more = __nss_next2 (nip, func_name, NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (nip, func_name, NULL, &fct, status, 0);
>
> if (is_last_nip)
> *last_nip = *nip;
> @@ -113,11 +109,7 @@ __nss_endent (const char *func_name, db_lookup_function lookup_fct,
> nss_action_list *nip, nss_action_list *startp,
> nss_action_list *last_nip, int res)
> {
> - union
> - {
> - endent_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more;
>
> struct resolv_context *res_ctx = NULL;
> @@ -132,17 +124,17 @@ __nss_endent (const char *func_name, db_lookup_function lookup_fct,
> }
>
> /* Cycle through all the services and run their endXXent functions. */
> - no_more = setup (func_name, lookup_fct, &fct.ptr, nip, startp, 1);
> + no_more = setup (func_name, lookup_fct, &fct, nip, startp, 1);
> while (! no_more)
> {
> /* Ignore status, we force check in __NSS_NEXT. */
> - DL_CALL_FCT (fct.f, ());
> + DL_CALL_FCT (((endent_function) fct), ());
>
> if (*nip == *last_nip)
> /* We have processed all services which were used. */
> break;
>
> - no_more = __nss_next2 (nip, func_name, NULL, &fct.ptr, 0, 1);
> + no_more = __nss_next2 (nip, func_name, NULL, &fct, 0, 1);
> }
> *last_nip = *nip = NULL;
>
> @@ -159,11 +151,7 @@ __nss_getent_r (const char *getent_func_name,
> void *resbuf, char *buffer, size_t buflen,
> void **result, int *h_errnop)
> {
> - union
> - {
> - getent_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> int no_more;
> enum nss_status status;
>
> @@ -185,13 +173,13 @@ __nss_getent_r (const char *getent_func_name,
> /* Run through available functions, starting with the same function last
> run. We will repeat each function as long as it succeeds, and then go
> on to the next service action. */
> - no_more = setup (getent_func_name, lookup_fct, &fct.ptr, nip,
> + no_more = setup (getent_func_name, lookup_fct, &fct, nip,
> startp, 0);
> while (! no_more)
> {
> int is_last_nip = *nip == *last_nip;
>
> - status = DL_CALL_FCT (fct.f,
> + status = DL_CALL_FCT (((getent_function) fct),
> (resbuf, buffer, buflen, &errno, &h_errno));
>
> /* The status is NSS_STATUS_TRYAGAIN and errno is ERANGE the
> @@ -216,7 +204,7 @@ __nss_getent_r (const char *getent_func_name,
> && nss_next_action (*nip, status) == NSS_ACTION_MERGE)
> no_more = 1;
> else
> - no_more = __nss_next2 (nip, getent_func_name, NULL, &fct.ptr,
> + no_more = __nss_next2 (nip, getent_func_name, NULL, &fct,
> status, 0);
>
> if (is_last_nip)
> @@ -225,20 +213,16 @@ __nss_getent_r (const char *getent_func_name,
> if (! no_more)
> {
> /* Call the `setXXent' function. This wasn't done before. */
> - union
> - {
> - setent_function f;
> - void *ptr;
> - } sfct;
> + void *sfct;
>
> - no_more = __nss_lookup (nip, setent_func_name, NULL, &sfct.ptr);
> + no_more = __nss_lookup (nip, setent_func_name, NULL, &sfct);
>
> if (! no_more)
> {
> if (stayopen_tmp)
> - status = DL_CALL_FCT (sfct.f, (*stayopen_tmp));
> + status = DL_CALL_FCT (((setent_function) sfct), (*stayopen_tmp));
> else
> - status = DL_CALL_FCT (sfct.f, (0));
> + status = DL_CALL_FCT (((setent_function) sfct), (0));
> }
> else
> status = NSS_STATUS_NOTFOUND;
> diff --git a/sunrpc/netname.c b/sunrpc/netname.c
> index d342fb8964..e2acf107a5 100644
> --- a/sunrpc/netname.c
> +++ b/sunrpc/netname.c
> @@ -157,21 +157,18 @@ netname2user (const char *netname, uid_t * uidp, gid_t * gidp,
> int *gidlenp, gid_t * gidlist)
> {
> nss_action_list nip;
> - union
> - {
> - netname2user_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> int no_more;
>
> - no_more = __nss_publickey_lookup2 (&nip, "netname2user", NULL, &fct.ptr);
> + no_more = __nss_publickey_lookup2 (&nip, "netname2user", NULL, &fct);
>
> while (!no_more)
> {
> - status = (*fct.f) (netname, uidp, gidp, gidlenp, gidlist);
> + status = ((netname2user_function) fct) (netname, uidp, gidp, gidlenp,
> + gidlist);
>
> - no_more = __nss_next2 (&nip, "netname2user", NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (&nip, "netname2user", NULL, &fct, status, 0);
> }
>
> return status == NSS_STATUS_SUCCESS;
> diff --git a/sunrpc/publickey.c b/sunrpc/publickey.c
> index 2480f8234c..812cb19ca0 100644
> --- a/sunrpc/publickey.c
> +++ b/sunrpc/publickey.c
> @@ -34,21 +34,17 @@ int
> getpublickey (const char *name, char *key)
> {
> nss_action_list nip;
> - union
> - {
> - public_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> int no_more;
>
> - no_more = __nss_publickey_lookup2 (&nip, "getpublickey", NULL, &fct.ptr);
> + no_more = __nss_publickey_lookup2 (&nip, "getpublickey", NULL, &fct);
>
> while (! no_more)
> {
> - status = (*fct.f) (name, key, &errno);
> + status = ((public_function) fct) (name, key, &errno);
>
> - no_more = __nss_next2 (&nip, "getpublickey", NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (&nip, "getpublickey", NULL, &fct, status, 0);
> }
>
> return status == NSS_STATUS_SUCCESS;
> @@ -60,21 +56,17 @@ int
> getsecretkey (const char *name, char *key, const char *passwd)
> {
> nss_action_list nip;
> - union
> - {
> - secret_function f;
> - void *ptr;
> - } fct;
> + void *fct;
> enum nss_status status = NSS_STATUS_UNAVAIL;
> int no_more;
>
> - no_more = __nss_publickey_lookup2 (&nip, "getsecretkey", NULL, &fct.ptr);
> + no_more = __nss_publickey_lookup2 (&nip, "getsecretkey", NULL, &fct);
>
> while (! no_more)
> {
> - status = (*fct.f) (name, key, passwd, &errno);
> + status = ((secret_function) fct) (name, key, passwd, &errno);
>
> - no_more = __nss_next2 (&nip, "getsecretkey", NULL, &fct.ptr, status, 0);
> + no_more = __nss_next2 (&nip, "getsecretkey", NULL, &fct, status, 0);
> }
>
> return status == NSS_STATUS_SUCCESS;
>
More information about the Libc-alpha
mailing list