Minor improvements around fgets(3) calls

[alejandro-colomar]

This is a subset of #1056 at v9e.

This PR improves style, in preparation for the following PR, which will remove fgetsx() and fputsx().

---

Revisions:

v2

• Fix bogus removal. It looks like an issue from a previous rebase.

$ git rd 
1:  60efe6d94 = 1:  60efe6d94 lib/, src/: Consistently use sizeof() as if it were a function
2:  ccf0e096c ! 2:  374ab381d lib/, src/: Remove useless casts in fgets(3)
    @@ Commit message
     
         Signed-off-by: Alejandro Colomar <alx@kernel.org>
     
    - ## lib/commonio.c ##
    -@@ lib/commonio.c: int commonio_open (struct commonio_db *db, int mode)
    - 
    -                   len = strlen (buf);
    -                   if (db->ops->cio_fgets(buf + len, buflen - len, db->fp) == NULL)
    --                          goto cleanup_buf;
    -           }
    -           stpsep(buf, "\n");
    - 
    -
      ## lib/setupenv.c ##
     @@ lib/setupenv.c: static void read_env_file (const char *filename)
        if (NULL == fp) {
3:  8572b8825 = 3:  4b4be6004 lib/, src/: Consistently use NULL with fgets(3)

v3

• Rebase

$ git rd 
1:  60efe6d94 ! 1:  1070be67a lib/, src/: Consistently use sizeof() as if it were a function
    @@ lib/log.c: void dolastlog (
        if (NULL != ll) {
                *ll = newlog;
     @@ lib/log.c: void dolastlog (
    -   STRNCPY(newlog.ll_host, host);
    +   strncpy_a(newlog.ll_host, host);
      #endif
        if (   (lseek (fd, offset, SEEK_SET) != offset)
     -      || (write_full(fd, &newlog, sizeof newlog) == -1)) {
    @@ lib/loginprompt.c: login_prompt(char *name, int namesize)
     @@ lib/loginprompt.c: login_prompt(char *name, int namesize)
         */
      
    -   MEMZERO(buf);
    +   memzero_a(buf);
     -  if (fgets (buf, sizeof buf, stdin) != buf) {
     +  if (fgets(buf, sizeof(buf), stdin) != buf) {
                exit (EXIT_FAILURE);
    @@ lib/utmp.c: failtmp(const char *username, const struct utmpx *failent)
        }
      
     @@ lib/utmp.c: prepare_utmp(const char *name, const char *line, const char *host,
    -           STRNCPY(utent->ut_host, hostname);
    +           strncpy_a(utent->ut_host, hostname);
      #endif
      #if defined(HAVE_STRUCT_UTMPX_UT_SYSLEN)
     -          utent->ut_syslen = MIN (strlen (hostname),
    @@ src/chage.c
     @@ src/chage.c: static int new_fields (void)
        (void) puts ("");
      
    -   SNPRINTF(buf, "%ld", mindays);
    +   stprintf_a(buf, "%ld", mindays);
     -  change_field (buf, sizeof buf, _("Minimum Password Age"));
     +  change_field(buf, sizeof(buf), _("Minimum Password Age"));
        if (a2sl(&mindays, buf, NULL, 0, -1, LONG_MAX) == -1)
                return 0;
      
    -   SNPRINTF(buf, "%ld", maxdays);
    +   stprintf_a(buf, "%ld", maxdays);
     -  change_field (buf, sizeof buf, _("Maximum Password Age"));
     +  change_field(buf, sizeof(buf), _("Maximum Password Age"));
        if (a2sl(&maxdays, buf, NULL, 0, -1, LONG_MAX) == -1)
    @@ src/chage.c: static int new_fields (void)
      
     @@ src/chage.c: static int new_fields (void)
        else
    -           DAY_TO_STR(buf, lstchgdate);
    +           day_to_str_a(buf, lstchgdate);
      
     -  change_field (buf, sizeof buf, _("Last Password Change (YYYY-MM-DD)"));
     +  change_field(buf, sizeof(buf), _("Last Password Change (YYYY-MM-DD)"));
    @@ src/chage.c: static int new_fields (void)
     @@ src/chage.c: static int new_fields (void)
        }
      
    -   SNPRINTF(buf, "%ld", warndays);
    +   stprintf_a(buf, "%ld", warndays);
     -  change_field (buf, sizeof buf, _("Password Expiration Warning"));
     +  change_field(buf, sizeof(buf), _("Password Expiration Warning"));
        if (a2sl(&warndays, buf, NULL, 0, -1, LONG_MAX) == -1)
                return 0;
      
    -   SNPRINTF(buf, "%ld", inactdays);
    +   stprintf_a(buf, "%ld", inactdays);
     -  change_field (buf, sizeof buf, _("Password Inactive"));
     +  change_field(buf, sizeof(buf), _("Password Inactive"));
        if (a2sl(&inactdays, buf, NULL, 0, -1, LONG_MAX) == -1)
    @@ src/chage.c: static int new_fields (void)
      
     @@ src/chage.c: static int new_fields (void)
        else
    -           DAY_TO_STR(buf, expdate);
    +           day_to_str_a(buf, expdate);
      
     -  change_field (buf, sizeof buf,
     +  change_field(buf, sizeof(buf),
    @@ src/login.c: int main (int argc, char **argv)
                /* Make the login prompt look like we want it */
     -          if (gethostname (hostn, sizeof (hostn)) == 0) {
     +          if (gethostname(hostn, sizeof(hostn)) == 0) {
    -                   SNPRINTF(loginprompt, _("%s login: "), hostn);
    +                   stprintf_a(loginprompt, _("%s login: "), hostn);
                } else {
    -                   STRTCPY(loginprompt, _("login: "));
    +                   strtcpy_a(loginprompt, _("login: "));
     @@ src/login.c: int main (int argc, char **argv)
      #ifdef HAVE_LL_HOST               /* __linux__ || SUN4 */
    -                   if (!STRNEQ(ll.ll_host, "")) {
    +                   if (!strneq_a(ll.ll_host, "")) {
                                printf (_(" from %.*s"),
     -                                  (int) sizeof ll.ll_host, ll.ll_host);
     +                                  (int) sizeof(ll.ll_host), ll.ll_host);
2:  374ab381d = 2:  b24f30953 lib/, src/: Remove useless casts in fgets(3)
3:  4b4be6004 ! 3:  712490882 lib/, src/: Consistently use NULL with fgets(3)
    @@ lib/loginprompt.c
     @@ lib/loginprompt.c: login_prompt(char *name, int namesize)
         */
      
    -   MEMZERO(buf);
    +   memzero_a(buf);
     -  if (fgets(buf, sizeof(buf), stdin) != buf) {
     +  if (fgets(buf, sizeof(buf), stdin) == NULL)
                exit (EXIT_FAILURE);

[hallyn]

LGTM - please ping me when you've rebased

[alejandro-colomar]

LGTM - please ping me when you've rebased

Thanks! Rebased.