3 files changed, 103 insertions, 54 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 651c48ba1..2519aeb98 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -587,10 +587,12 @@ enum {
 };
 #if BB_MMU
   void forkexit_or_rexec(void);
+  enum { re_execed = 0 };
 # define forkexit_or_rexec(argv)            forkexit_or_rexec()
 # define bb_daemonize_or_rexec(flags, argv) bb_daemonize_or_rexec(flags)
 # define bb_daemonize(flags)                bb_daemonize_or_rexec(flags, bogus)
 #else
+  void re_exec(char **argv) ATTRIBUTE_NORETURN;
   void forkexit_or_rexec(char **argv);
   extern bool re_execed;
 # define fork()          BUG_fork_is_unavailable_on_nommu()
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index f7c620996..558510bc6 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -203,6 +203,15 @@ int spawn_and_wait(char **argv)
 }
 
 #if !BB_MMU
+void re_exec(char **argv)
+{
+        /* high-order bit of first char in argv[0] is a hidden
+         * "we have (already) re-execed, don't do it again" flag */
+        argv[0][0] |= 0x80;
+        execv(bb_busybox_exec_path, argv);
+        bb_perror_msg_and_die("exec %s", bb_busybox_exec_path);
+}
+
 void forkexit_or_rexec(char **argv)
 {
         pid_t pid;
@@ -216,11 +225,7 @@ void forkexit_or_rexec(char **argv)
         if (pid) /* parent */
                 exit(0);
         /* child - re-exec ourself */
-        /* high-order bit of first char in argv[0] is a hidden
-         * "we have (alrealy) re-execed, don't do it again" flag */
-        argv[0][0] |= 0x80;
-        execv(bb_busybox_exec_path, argv);
-        bb_perror_msg_and_die("exec %s", bb_busybox_exec_path);
+        re_exec(argv);
 }
 #else
 /* Dance around (void)...*/
diff --git a/networking/httpd.c b/networking/httpd.c
index d68dc06e9..cd46f49ef 100644
--- a/networking/httpd.c
+++ b/networking/httpd.c
@@ -764,7 +764,6 @@ static void decodeBase64(char *Data)
 /*
  * Create a listen server socket on the designated port.
  */
-#if BB_MMU
 static int openServer(void)
 {
         int n = bb_strtou(bind_addr_or_port, NULL, 10);
@@ -775,7 +774,6 @@ static int openServer(void)
         xlisten(n, 9);
         return n;
 }
-#endif
 
 /*
  * Log the connection closure and exit.
@@ -1474,8 +1472,8 @@ static void exit_on_signal(int sig)
 /*
  * Handle an incoming http request and exit.
  */
-static void handle_incoming_and_exit(void) ATTRIBUTE_NORETURN;
-static void handle_incoming_and_exit(void)
+static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) ATTRIBUTE_NORETURN;
+static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
 {
         static const char request_GET[] ALIGN1 = "GET";
 
@@ -1497,6 +1495,22 @@ static void handle_incoming_and_exit(void)
         int credentials = -1;  /* if not required this is Ok */
 #endif
 
+        rmt_port = get_nport(&fromAddr->sa);
+        rmt_port = ntohs(rmt_port);
+        rmt_ip = 0;
+        if (fromAddr->sa.sa_family == AF_INET) {
+                rmt_ip = ntohl(fromAddr->sin.sin_addr.s_addr);
+        }
+        if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
+                rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->sa);
+        }
+        if (verbose) {
+                /* this trick makes -v logging much simpler */
+                applet_name = rmt_ip_str;
+                if (verbose > 2)
+                        bb_error_msg("connected");
+        }
+
         /* Install timeout handler */
         memset(&sa, 0, sizeof(sa));
         sa.sa_handler = exit_on_signal;
@@ -1772,13 +1786,13 @@ static void handle_incoming_and_exit(void)
 #endif
 }
 
-#if BB_MMU
 /*
  * The main http server function.
- * Given an open socket, listen for new connections and farm out
- * the processing as a forked process.
+ * Given a socket, listen for new connections and farm out
+ * the processing as a [v]forked process.
  * Never returns.
  */
+#if BB_MMU
 static void mini_httpd(int server_socket) ATTRIBUTE_NORETURN;
 static void mini_httpd(int server_socket)
 {
@@ -1810,22 +1824,53 @@ static void mini_httpd(int server_socket)
                         xmove_fd(n, 0);
                         xdup2(0, 1);
 
-                        n = get_nport(&fromAddr.sa);
-                        rmt_port = ntohs(n);
-                        rmt_ip = 0;
-                        if (fromAddr.sa.sa_family == AF_INET) {
-                                rmt_ip = ntohl(fromAddr.sin.sin_addr.s_addr);
-                        }
-                        if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
-                                rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr.sa);
-                        }
-                        if (verbose) {
-                                /* this trick makes -v logging much simpler */
-                                applet_name = rmt_ip_str;
-                                if (verbose > 2)
-                                        bb_error_msg("connected");
-                        }
-                        handle_incoming_and_exit();
+                        handle_incoming_and_exit(&fromAddr);
+                }
+                /* parent, or fork failed */
+                close(n);
+        } /* while (1) */
+        /* never reached */
+}
+#else
+static void mini_httpd_nommu(int server_socket, int argc, char **argv) ATTRIBUTE_NORETURN;
+static void mini_httpd_nommu(int server_socket, int argc, char **argv)
+{
+        char *argv_copy[argc + 2];
+
+        argv_copy[0] = argv[0];
+        argv_copy[1] = (char*)"-i";
+        memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
+
+        /* NB: it's best to not use xfuncs in this loop before vfork().
+         * Otherwise server may die on transient errors (temporary
+         * out-of-memory condition, etc), which is Bad(tm).
+         * Try to do any dangerous calls after fork.
+         */
+        while (1) {
+                int n;
+                len_and_sockaddr fromAddr;
+                
+                /* Wait for connections... */
+                fromAddr.len = LSA_SIZEOF_SA;
+                n = accept(server_socket, &fromAddr.sa, &fromAddr.len);
+
+                if (n < 0)
+                        continue;
+                /* set the KEEPALIVE option to cull dead connections */
+                setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+
+                if (vfork() == 0) {
+                        /* child */
+#if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
+                        /* Do not reload config on HUP */
+                        signal(SIGHUP, SIG_IGN);
+#endif
+                        close(server_socket);
+                        xmove_fd(n, 0);
+                        xdup2(0, 1);
+
+                        /* Run a copy of ourself in inetd mode */
+                        re_exec(argv_copy);
                 }
                 /* parent, or fork failed */
                 close(n);
@@ -1834,25 +1879,18 @@ static void mini_httpd(int server_socket)
 }
 #endif
 
-/* from inetd */
+/*
+ * Process a HTTP connection on stdin/out.
+ * Never returns.
+ */
 static void mini_httpd_inetd(void) ATTRIBUTE_NORETURN;
 static void mini_httpd_inetd(void)
 {
-        int n;
         len_and_sockaddr fromAddr;
 
         fromAddr.len = LSA_SIZEOF_SA;
         getpeername(0, &fromAddr.sa, &fromAddr.len);
-        n = get_nport(&fromAddr.sa);
-        rmt_port = ntohs(n);
-        rmt_ip = 0;
-        if (fromAddr.sa.sa_family == AF_INET) {
-                rmt_ip = ntohl(fromAddr.sin.sin_addr.s_addr);
-        }
-        if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
-                rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr.sa);
-        }
-        handle_incoming_and_exit();
+        handle_incoming_and_exit(&fromAddr);
 }
 
 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
@@ -1915,7 +1953,8 @@ int httpd_main(int argc, char **argv)
 #endif
 
         home_httpd = xrealloc_getcwd_or_warn(NULL);
-        opt_complementary = "vv"; /* counter */
+        /* -v counts, -i implies -f */
+        opt_complementary = "vv:if";
         /* We do not "absolutize" path given by -h (home) opt.
          * If user gives relative path in -h, $SCRIPT_FILENAME can end up
          * relative too. */
@@ -1934,12 +1973,12 @@ int httpd_main(int argc, char **argv)
                         , &verbose
                 );
         if (opt & OPT_DECODE_URL) {
-                printf("%s", decodeString(url_for_decode, 1));
+                fputs(decodeString(url_for_decode, 1), stdout);
                 return 0;
         }
 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
         if (opt & OPT_ENCODE_URL) {
-                printf("%s", encodeString(url_for_encode));
+                fputs(encodeString(url_for_encode), stdout);
                 return 0;
         }
 #endif
@@ -1957,9 +1996,14 @@ int httpd_main(int argc, char **argv)
         }
 #endif
 
+#if !BB_MMU
+        if (!(opt & OPT_FOREGROUND)) {
+                bb_daemonize_or_rexec(0, argv); /* don't change current directory */
+        }
+#endif
+
         xchdir(home_httpd);
         if (!(opt & OPT_INETD)) {
-#if BB_MMU
                 signal(SIGCHLD, SIG_IGN);
                 server_socket = openServer();
 #if ENABLE_FEATURE_HTTPD_SETUID
@@ -1973,9 +2017,6 @@ int httpd_main(int argc, char **argv)
                         xsetuid(ugid.uid);
                 }
 #endif
-#else   /* BB_MMU */
-                bb_error_msg_and_die("-i is required");
-#endif
         }
 
 #if ENABLE_FEATURE_HTTPD_CGI
@@ -1990,21 +2031,22 @@ int httpd_main(int argc, char **argv)
         }
 #endif
 
-#if BB_MMU
 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
-        sighup_handler(0);
-#else
-        parse_conf(default_path_httpd_conf, FIRST_PARSE);
+        if (!(opt & OPT_INETD))
+                sighup_handler(0);
+        else /* do not install HUP handler in inetd mode */
 #endif
+                parse_conf(default_path_httpd_conf, FIRST_PARSE);
+
         xfunc_error_retval = 0;
         if (opt & OPT_INETD)
                 mini_httpd_inetd();
+#if BB_MMU
         if (!(opt & OPT_FOREGROUND))
                 bb_daemonize(0); /* don't change current directory */
         mini_httpd(server_socket); /* never returns */
 #else
-        xfunc_error_retval = 0;
-        mini_httpd_inetd(); /* never returns */
-        /* return 0; */
+        mini_httpd_nommu(server_socket, argc, argv); /* never returns */
 #endif
+        /* return 0; */
 }