*: intrduce and use safe_gethostname. By Tito <farmatito AT tiscali.it>

safe_gethostname                                       -      48     +48
glob3                                                 35      37      +2
timestamp_and_log                                    314     315      +1
udhcp_send_kernel_packet                             234     231      -3
scan_tree                                            275     271      -4
passwd_main                                         1074    1070      -4
print_login_prompt                                    68      58     -10
obscure                                              392     377     -15
syslogd_main                                         882     866     -16
print_login_issue                                    516     478     -38
hostname_main                                        278     223     -55
parse_and_put_prompt                                 825     756     -69
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/9 up/down: 51/-214)          Total: -163 bytes
   text    data     bss     dec     hex filename
 798791     728    7484  807003   c505b busybox_old
 798631     728    7484  806843   c4fbb busybox_unstripped

8 files changed, 32 insertions, 45 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 1ea2e35be..978cd2d87 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -550,6 +550,8 @@ extern FILE *fopen_or_warn_stdin(const char *filename);
  * If this is a problem, use bare poll and open-code EINTR/ENOMEM handling */
 int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout_ms);
 
+char *safe_gethostname(void);
+
 /* Convert each alpha char in str to lower-case */
 char* str_tolower(char *str);
 
diff --git a/libbb/Kbuild b/libbb/Kbuild
index 515368de7..aab016e85 100644
--- a/libbb/Kbuild
+++ b/libbb/Kbuild
@@ -73,6 +73,7 @@ lib-y += recursive_action.o
 lib-y += remove_file.o
 lib-y += restricted_shell.o
 lib-y += run_shell.o
+lib-y += safe_gethostname.o
 lib-y += safe_poll.o
 lib-y += safe_strncpy.o
 lib-y += safe_write.o
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 9aab63702..c6aa45c93 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -1203,11 +1203,7 @@ static void parse_and_put_prompt(const char *prmt_ptr)
                                         break;
 #endif
                                 case 'h':
-                                        pbuf = free_me = xzalloc(256);
-                                        if (gethostname(pbuf, 255) < 0) {
-                                                pbuf[0] = '?';
-                                                pbuf[1] = '\0';
-                                        }
+                                        pbuf = free_me = safe_gethostname();
                                         *strchrnul(pbuf, '.') = '\0';
                                         break;
                                 case '$':
diff --git a/libbb/login.c b/libbb/login.c
index d1f5d6498..a711a5437 100644
--- a/libbb/login.c
+++ b/libbb/login.c
@@ -50,6 +50,7 @@ void print_login_issue(const char *issue_file, const char *tty)
                                 outbuf = uts.sysname;
                                 break;
                         case 'n':
+                        case 'h':
                                 outbuf = uts.nodename;
                                 break;
                         case 'r':
@@ -72,10 +73,6 @@ void print_login_issue(const char *issue_file, const char *tty)
                         case 't':
                                 strftime(buf, sizeof(buf), fmtstr_t, localtime(&t));
                                 break;
-                        case 'h':
-                                gethostname(buf, sizeof(buf) - 1);
-                                buf[sizeof(buf) - 1] = '\0';
-                                break;
                         case 'l':
                                 outbuf = tty;
                                 break;
@@ -91,13 +88,12 @@ void print_login_issue(const char *issue_file, const char *tty)
 
 void print_login_prompt(void)
 {
-        char buf[MAXHOSTNAMELEN+1];
-
-        if (gethostname(buf, MAXHOSTNAMELEN) == 0)
-                fputs(buf, stdout);
-
+        char *hostname = safe_gethostname();
+        
+        fputs(hostname, stdout);
         fputs(LOGIN, stdout);
         fflush(stdout);
+        free(hostname);
 }
 
 /* Clear dangerous stuff, set PATH */
diff --git a/libbb/obscure.c b/libbb/obscure.c
index 5cc906235..1841b27d6 100644
--- a/libbb/obscure.c
+++ b/libbb/obscure.c
@@ -93,7 +93,7 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
         /* Add 2 for each type of characters to the minlen of password */
         int size = CONFIG_PASSWORD_MINLEN + 8;
         const char *p;
-        char hostname[255];
+        char *hostname;
 
         /* size */
         if (!new_p || (length = strlen(new_p)) < CONFIG_PASSWORD_MINLEN)
@@ -108,12 +108,11 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
                 return "similar to gecos";
         }
         /* hostname as-is, as sub-string, reversed, capitalized, doubled */
-        if (gethostname(hostname, 255) == 0) {
-                hostname[254] = '\0';
-                if (string_checker(new_p, hostname)) {
-                        return "similar to hostname";
-                }
-        }
+        hostname = safe_gethostname();
+        i = string_checker(new_p, hostname);
+        free(hostname);
+        if (i)
+                return "similar to hostname";
 
         /* Should / Must contain a mix of: */
         for (i = 0; i < length; i++) {
diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c
index 52a65bc98..286f00fd8 100644
--- a/miscutils/devfsd.c
+++ b/miscutils/devfsd.c
@@ -1133,8 +1133,8 @@ static void signal_handler(int sig)
 static const char *get_variable(const char *variable, void *info)
 {
         static char sbuf[sizeof(int)*3 + 2]; /* sign and NUL */
+        static char *hostname;
 
-        char hostname[STRING_LENGTH];
         struct get_variable_info *gv_info = info;
         const char *field_names[] = {
                         "hostname", "mntpt", "devpath", "devname",
@@ -1143,12 +1143,8 @@ static const char *get_variable(const char *variable, void *info)
         };
         int i;
 
-        if (gethostname(hostname, STRING_LENGTH - 1) != 0)
-                /* Here on error we should do exit(RV_SYS_ERROR), instead we do exit(EXIT_FAILURE) */
-                error_logger_and_die(LOG_ERR, "gethostname");
-
-        hostname[STRING_LENGTH - 1] = '\0';
-
+        if (!hostname)
+                hostname = safe_gethostname();
         /* index_in_str_array returns i>=0  */
         i = index_in_str_array(field_names, variable);
 
diff --git a/networking/hostname.c b/networking/hostname.c
index 2c224bef9..93cbc961f 100644
--- a/networking/hostname.c
+++ b/networking/hostname.c
@@ -24,8 +24,7 @@ static void do_sethostname(char *s, int isfile)
                 if (sethostname(s, strlen(s)) < 0) {
                         if (errno == EPERM)
                                 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
-                        else
-                                bb_perror_msg_and_die("sethostname");
+                        bb_perror_msg_and_die("sethostname");
                 }
         } else {
                 f = xfopen(s, "r");
@@ -54,27 +53,27 @@ int hostname_main(int argc, char **argv)
                 OPT_dfis = 0xf,
         };
 
-        char buf[256];
+        char *buf;
         char *hostname_str;
 
         if (argc < 1)
                 bb_show_usage();
 
         getopt32(argv, "dfisF:", &hostname_str);
+        argv += optind;
+        buf = safe_gethostname();
 
         /* Output in desired format */
         if (option_mask32 & OPT_dfis) {
                 struct hostent *hp;
                 char *p;
-                gethostname(buf, sizeof(buf));
                 hp = xgethostbyname(buf);
                 p = strchr(hp->h_name, '.');
                 if (option_mask32 & OPT_f) {
                         puts(hp->h_name);
                 } else if (option_mask32 & OPT_s) {
-                        if (p != NULL) {
+                        if (p)
                                 *p = '\0';
-                        }
                         puts(hp->h_name);
                 } else if (option_mask32 & OPT_d) {
                         if (p)
@@ -89,14 +88,15 @@ int hostname_main(int argc, char **argv)
         /* Set the hostname */
         else if (option_mask32 & OPT_F) {
                 do_sethostname(hostname_str, 1);
-        } else if (optind < argc) {
-                do_sethostname(argv[optind], 0);
+        } else if (argv[0]) {
+                do_sethostname(argv[0], 0);
         }
         /* Or if all else fails,
          * just print the current hostname */
         else {
-                gethostname(buf, sizeof(buf));
                 puts(buf);
         }
+        if (ENABLE_FEATURE_CLEAN_UP)
+                free(buf);
         return 0;
 }
diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index 0dc69d8cc..0d004bc27 100644
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -97,8 +97,8 @@ struct globals {
         struct shbuf_ds *shbuf;
 #endif
         time_t last_log_time;
-        /* localhost's name */
-        char localHostName[64];
+        /* localhost's name. We print only first 64 chars */
+        char *hostname;
 
         /* We recv into recvbuf... */
         char recvbuf[MAX_READ];
@@ -416,7 +416,7 @@ static void timestamp_and_log(int pri, char *msg, int len)
         else {
                 char res[20];
                 parse_fac_prio_20(pri, res);
-                sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
+                sprintf(G.printbuf, "%s %.64s %s %s\n", timestamp, G.hostname, res, msg);
         }
 
         /* Log message locally (to file or shared mem) */
@@ -647,11 +647,8 @@ int syslogd_main(int argc, char **argv)
                 option_mask32 |= OPT_locallog;
 
         /* Store away localhost's name before the fork */
-        /* "It is unspecified whether the truncated hostname
-         * will be null-terminated". We give it (size - 1),
-         * thus last byte will be NUL no matter what. */
-        gethostname(G.localHostName, sizeof(G.localHostName) - 1);
-        *strchrnul(G.localHostName, '.') = '\0';
+        G.hostname = safe_gethostname();
+        *strchrnul(G.hostname, '.') = '\0';
 
         if (!(option_mask32 & OPT_nofork)) {
                 bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);