make standalone httpd work on NOMMU machines

diff --git a/include/libbb.h b/include/libbb.h
index 651c48b..2519aeb 100644 (file)
--- 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 f7c6209..558510b 100644 (file)
--- 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 d68dc06..cd46f49 100644 (file)
--- 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; */
 }