Changeset 2725 in MondoRescue for branches/2.2.9/mindi-busybox/networking/ifupdown.c

Timestamp:

Feb 25, 2011, 9:26:54 PM (13 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3

File:

• branches/2.2.9/mindi-busybox/networking/ifupdown.c (modified) (50 diffs)

branches/2.2.9/mindi-busybox/networking/ifupdown.c

@@ -2 +2 @@
 /*
  *  ifupdown for busybox
- *  Copyright (c) 2002 Glenn McGrath <bug1@iinet.net.au>
+ *  Copyright (c) 2002 Glenn McGrath
  *  Copyright (c) 2003-2004 Erik Andersen <andersen@codepoet.org>
  *
@@ -15 +15 @@
  *  configuration.
  *
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
+#include "libbb.h"
+/* After libbb.h, since it needs sys/types.h on some systems */
 #include <sys/utsname.h>
 #include <fnmatch.h>
-#include <getopt.h>
-
-#include "libbb.h"
 
 #define MAX_OPT_DEPTH 10
@@ -33 +32 @@
 #endif
 
+#define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
+
 #define debug_noise(args...) /*fprintf(stderr, args)*/
 
@@ -42 +43 @@
 struct method_t {
     const char *name;
-    int (*up)(struct interface_defn_t *ifd, execfn *e);
-    int (*down)(struct interface_defn_t *ifd, execfn *e);
+    int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
+    int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
 };
 
@@ -87 +88 @@
 };
 
-#define OPTION_STR "anvf" USE_FEATURE_IFUPDOWN_MAPPING("m") "i:"
+
+#define OPTION_STR "anvf" IF_FEATURE_IFUPDOWN_MAPPING("m") "i:"
 enum {
-    OPT_do_all = 0x1,
-    OPT_no_act = 0x2,
-    OPT_verbose = 0x4,
-    OPT_force = 0x8,
+    OPT_do_all      = 0x1,
+    OPT_no_act      = 0x2,
+    OPT_verbose     = 0x4,
+    OPT_force       = 0x8,
     OPT_no_mappings = 0x10,
 };
-#define DO_ALL (option_mask32 & OPT_do_all)
-#define NO_ACT (option_mask32 & OPT_no_act)
-#define VERBOSE (option_mask32 & OPT_verbose)
-#define FORCE (option_mask32 & OPT_force)
+#define DO_ALL      (option_mask32 & OPT_do_all)
+#define NO_ACT      (option_mask32 & OPT_no_act)
+#define VERBOSE     (option_mask32 & OPT_verbose)
+#define FORCE       (option_mask32 & OPT_force)
 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
 
-static char **my_environ;
-
-static const char *startup_PATH;
+
+struct globals {
+    char **my_environ;
+    const char *startup_PATH;
+} FIX_ALIASING;
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define INIT_G() do { } while (0)
+
 
 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
@@ -126 +133 @@
 
     if (i == 0)
-        return -r[llen];
+        return - (unsigned char)r[llen];
     return i;
 }
@@ -135 +142 @@
 
     if (strncmpz(id, "iface", idlen) == 0) {
-        char *result;
-        static char label_buf[20];
-        safe_strncpy(label_buf, ifd->iface, sizeof(label_buf));
-        result = strchr(label_buf, ':');
-        if (result) {
-            *result = '\0';
-        }
-        return label_buf;
+        // ubuntu's ifup doesn't do this:
+        //static char *label_buf;
+        //char *result;
+        //free(label_buf);
+        //label_buf = xstrdup(ifd->iface);
+        // Remove virtual iface suffix
+        //result = strchrnul(label_buf, ':');
+        //*result = '\0';
+        //return label_buf;
+
+        return ifd->iface;
     }
     if (strncmpz(id, "label", idlen) == 0) {
@@ -155 +165 @@
 }
 
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# if ENABLE_FEATURE_IFUPDOWN_IP
 static int count_netmask_bits(const char *dotted_quad)
 {
@@ -186 +196 @@
     return result;
 }
-#endif
+# endif
 
 static char *parse(const char *command, struct interface_defn_t *ifd)
@@ -249 +259 @@
 
                 if (varvalue) {
+# if ENABLE_FEATURE_IFUPDOWN_IP
+                    /* "hwaddress <class> <address>":
+                     * unlike ifconfig, ip doesnt want <class>
+                     * (usually "ether" keyword). Skip it. */
+                    if (strncmp(command, "hwaddress", 9) == 0) {
+                        varvalue = skip_whitespace(skip_non_whitespace(varvalue));
+                    }
+# endif
                     addstr(&result, varvalue, strlen(varvalue));
                 } else {
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# if ENABLE_FEATURE_IFUPDOWN_IP
                     /* Sigh...  Add a special case for 'ip' to convert from
                      * dotted quad to bit count style netmasks.  */
@@ -267 +285 @@
                         }
                     }
-#endif
+# endif
                     okay[opt_depth - 1] = 0;
                 }
@@ -312 +330 @@
     return 1;
 }
-#endif
+
+#endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
+
 
 #if ENABLE_FEATURE_IFUPDOWN_IPV6
-static int loopback_up6(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_IP
+
+static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
+{
+# if ENABLE_FEATURE_IFUPDOWN_IP
     int result;
     result = execute("ip addr add ::1 dev %iface%", ifd, exec);
     result += execute("ip link set %iface% up", ifd, exec);
     return ((result == 2) ? 2 : 0);
-#else
+# else
     return execute("ifconfig %iface% add ::1", ifd, exec);
-#endif
-}
-
-static int loopback_down6(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# endif
+}
+
+static int FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
+{
+# if ENABLE_FEATURE_IFUPDOWN_IP
     return execute("ip link set %iface% down", ifd, exec);
-#else
+# else
     return execute("ifconfig %iface% del ::1", ifd, exec);
-#endif
-}
-
-static int static_up6(struct interface_defn_t *ifd, execfn *exec)
+# endif
+}
+
+static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
+{
+    return 1;
+}
+
+static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
 {
     int result;
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# if ENABLE_FEATURE_IFUPDOWN_IP
     result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
-    result += execute("ip link set[[ mtu %mtu%]][[ address %hwaddress%]] %iface% up", ifd, exec);
+    result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
     /* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
     result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
-#else
+# else
     result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
     result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
     result += execute("[[route -A inet6 add ::/0 gw %gateway%]]", ifd, exec);
-#endif
+# endif
     return ((result == 3) ? 3 : 0);
 }
 
-static int static_down6(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_IP
+static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
+{
+# if ENABLE_FEATURE_IFUPDOWN_IP
     return execute("ip link set %iface% down", ifd, exec);
-#else
+# else
     return execute("ifconfig %iface% down", ifd, exec);
-#endif
-}
-
-#if ENABLE_FEATURE_IFUPDOWN_IP
-static int v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
+# endif
+}
+
+# if ENABLE_FEATURE_IFUPDOWN_IP
+static int FAST_FUNC v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 {
     int result;
@@ -373 +399 @@
 }
 
-static int v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
+static int FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 {
     return execute("ip tunnel del %iface%", ifd, exec);
 }
-#endif
+# endif
 
 static const struct method_t methods6[] = {
-#if ENABLE_FEATURE_IFUPDOWN_IP
-    { "v4tunnel", v4tunnel_up, v4tunnel_down, },
-#endif
-    { "static", static_up6, static_down6, },
-    { "loopback", loopback_up6, loopback_down6, },
+# if ENABLE_FEATURE_IFUPDOWN_IP
+    { "v4tunnel" , v4tunnel_up     , v4tunnel_down   , },
+# endif
+    { "static"   , static_up6      , static_down6    , },
+    { "manual"   , manual_up_down6 , manual_up_down6 , },
+    { "loopback" , loopback_up6    , loopback_down6  , },
 };
 
@@ -392 +419 @@
     methods6
 };
+
 #endif /* FEATURE_IFUPDOWN_IPV6 */
 
+
 #if ENABLE_FEATURE_IFUPDOWN_IPV4
-static int loopback_up(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_IP
+
+static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
+{
+# if ENABLE_FEATURE_IFUPDOWN_IP
     int result;
     result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
     result += execute("ip link set %iface% up", ifd, exec);
     return ((result == 2) ? 2 : 0);
-#else
+# else
     return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
-#endif
-}
-
-static int loopback_down(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# endif
+}
+
+static int FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
+{
+# if ENABLE_FEATURE_IFUPDOWN_IP
     int result;
     result = execute("ip addr flush dev %iface%", ifd, exec);
     result += execute("ip link set %iface% down", ifd, exec);
     return ((result == 2) ? 2 : 0);
-#else
+# else
     return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
-#endif
-}
-
-static int static_up(struct interface_defn_t *ifd, execfn *exec)
+# endif
+}
+
+static int FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
 {
     int result;
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# if ENABLE_FEATURE_IFUPDOWN_IP
     result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
             "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
-    result += execute("ip link set[[ mtu %mtu%]][[ address %hwaddress%]] %iface% up", ifd, exec);
+    result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
     result += execute("[[ip route add default via %gateway% dev %iface%]]", ifd, exec);
     return ((result == 3) ? 3 : 0);
-#else
+# else
     /* ifconfig said to set iface up before it processes hw %hwaddress%,
      * which then of course fails. Thus we run two separate ifconfig */
@@ -438 +468 @@
     result += execute("[[route add default gw %gateway% %iface%]]", ifd, exec);
     return ((result == 3) ? 3 : 0);
-#endif
-}
-
-static int static_down(struct interface_defn_t *ifd, execfn *exec)
+# endif
+}
+
+static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
 {
     int result;
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# if ENABLE_FEATURE_IFUPDOWN_IP
     result = execute("ip addr flush dev %iface%", ifd, exec);
     result += execute("ip link set %iface% down", ifd, exec);
-#else
-    result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec);
+# else
+    /* result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec); */
+    /* Bringing the interface down deletes the routes in itself.
+       Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
+    result = 1;
     result += execute("ifconfig %iface% down", ifd, exec);
-#endif
+# endif
     return ((result == 2) ? 2 : 0);
 }
 
-#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
-struct dhcp_client_t
-{
+# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
+struct dhcp_client_t {
     const char *name;
     const char *startcmd;
@@ -464 +496 @@
 static const struct dhcp_client_t ext_dhcp_clients[] = {
     { "dhcpcd",
-        "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %clientid%]][[ -l %leasetime%]] %iface%",
+        "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
         "dhcpcd -k %iface%",
     },
@@ -476 +508 @@
     },
     { "udhcpc",
-        "udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
+        "udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %client%]]"
+                "[[ -s %script%]][[ %udhcpc_opts%]]",
         "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
     },
 };
-#endif /* ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
-
-static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
-    int i;
-#if ENABLE_FEATURE_IFUPDOWN_IP
+# endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
+
+# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
+static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
+{
+    unsigned i;
+#  if ENABLE_FEATURE_IFUPDOWN_IP
     /* ip doesn't up iface when it configures it (unlike ifconfig) */
-    if (!execute("ip link set %iface% up", ifd, exec))
+    if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
         return 0;
-#endif
+#  else
+    /* needed if we have hwaddress on dhcp iface */
+    if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
+        return 0;
+#  endif
     for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
         if (exists_execable(ext_dhcp_clients[i].name))
@@ -497 +534 @@
     bb_error_msg("no dhcp clients found");
     return 0;
-#elif ENABLE_APP_UDHCPC
-#if ENABLE_FEATURE_IFUPDOWN_IP
+}
+# elif ENABLE_UDHCPC
+static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
+{
+#  if ENABLE_FEATURE_IFUPDOWN_IP
     /* ip doesn't up iface when it configures it (unlike ifconfig) */
-    if (!execute("ip link set %iface% up", ifd, exec))
+    if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
         return 0;
-#endif
-    return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
-            "-i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
+#  else
+    /* needed if we have hwaddress on dhcp iface */
+    if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
+        return 0;
+#  endif
+    return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
+            "-i %iface%[[ -H %hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
             ifd, exec);
-#else
+}
+# else
+static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
+        execfn *exec UNUSED_PARAM)
+{
     return 0; /* no dhcp support */
-#endif
-}
-
-static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
-{
-#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
-    int i;
+}
+# endif
+
+# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
+static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
+{
+    int result = 0;
+    unsigned i;
+
     for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
-        if (exists_execable(ext_dhcp_clients[i].name))
-            return execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
-    }
-    bb_error_msg("no dhcp clients found, using static interface shutdown");
-    return static_down(ifd, exec);
-#elif ENABLE_APP_UDHCPC
-    return execute("kill "
-                   "`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
-#else
+        if (exists_execable(ext_dhcp_clients[i].name)) {
+            result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
+            if (result)
+                break;
+        }
+    }
+
+    if (!result)
+        bb_error_msg("warning: no dhcp clients found and stopped");
+
+    /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
+       and it may come back up because udhcpc is still shutting down */
+    usleep(100000);
+    result += static_down(ifd, exec);
+    return ((result == 3) ? 3 : 0);
+}
+# elif ENABLE_UDHCPC
+static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
+{
+    int result;
+    result = execute(
+        "test -f /var/run/udhcpc.%iface%.pid && "
+        "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
+        ifd, exec);
+    /* Also bring the hardware interface down since
+       killing the dhcp client alone doesn't do it.
+       This enables consecutive ifup->ifdown->ifup */
+    /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
+       and it may come back up because udhcpc is still shutting down */
+    usleep(100000);
+    result += static_down(ifd, exec);
+    return ((result == 3) ? 3 : 0);
+}
+# else
+static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
+        execfn *exec UNUSED_PARAM)
+{
     return 0; /* no dhcp support */
-#endif
-}
-
-static int manual_up_down(struct interface_defn_t *ifd, execfn *exec)
+}
+# endif
+
+static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 {
     return 1;
 }
 
-static int bootp_up(struct interface_defn_t *ifd, execfn *exec)
+static int FAST_FUNC bootp_up(struct interface_defn_t *ifd, execfn *exec)
 {
     return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
@@ -541 +619 @@
 }
 
-static int ppp_up(struct interface_defn_t *ifd, execfn *exec)
+static int FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
 {
     return execute("pon[[ %provider%]]", ifd, exec);
 }
 
-static int ppp_down(struct interface_defn_t *ifd, execfn *exec)
+static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
 {
     return execute("poff[[ %provider%]]", ifd, exec);
 }
 
-static int wvdial_up(struct interface_defn_t *ifd, execfn *exec)
+static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 {
     return execute("start-stop-daemon --start -x wvdial "
@@ -557 +635 @@
 }
 
-static int wvdial_down(struct interface_defn_t *ifd, execfn *exec)
+static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 {
     return execute("start-stop-daemon --stop -x wvdial "
@@ -564 +642 @@
 
 static const struct method_t methods[] = {
-    { "manual", manual_up_down, manual_up_down, },
-    { "wvdial", wvdial_up, wvdial_down, },
-    { "ppp", ppp_up, ppp_down, },
-    { "static", static_up, static_down, },
-    { "bootp", bootp_up, static_down, },
-    { "dhcp", dhcp_up, dhcp_down, },
-    { "loopback", loopback_up, loopback_down, },
+    { "manual"  , manual_up_down, manual_up_down, },
+    { "wvdial"  , wvdial_up     , wvdial_down   , },
+    { "ppp"     , ppp_up        , ppp_down      , },
+    { "static"  , static_up     , static_down   , },
+    { "bootp"   , bootp_up      , static_down   , },
+    { "dhcp"    , dhcp_up       , dhcp_down     , },
+    { "loopback", loopback_up   , loopback_down , },
 };
 
@@ -579 +657 @@
 };
 
-#endif  /* if ENABLE_FEATURE_IFUPDOWN_IPV4 */
-
+#endif  /* FEATURE_IFUPDOWN_IPV4 */
+
+
+/* Returns pointer to the next word, or NULL.
+ * In 1st case, advances *buf to the word after this one.
+ */
 static char *next_word(char **buf)
 {
-    unsigned short length;
+    unsigned length;
     char *word;
-
-    if (!buf || !*buf || !**buf) {
-        return NULL;
-    }
 
     /* Skip over leading whitespace */
     word = skip_whitespace(*buf);
 
-    /* Skip over comments */
-    if (*word == '#') {
+    /* Stop on EOL */
+    if (*word == '\0')
         return NULL;
-    }
-
-    /* Find the length of this word */
+
+    /* Find the length of this word (can't be 0) */
     length = strcspn(word, " \t\n");
-    if (length == 0) {
-        return NULL;
-    }
-    *buf = word + length;
-    /*DBU:[dave@cray.com] if we are already at EOL dont't increment beyond it */
-    if (**buf) {
-        **buf = '\0';
-        (*buf)++;
-    }
+
+    /* Unless we are already at NUL, store NUL and advance */
+    if (word[length] != '\0')
+        word[length++] = '\0';
+
+    *buf = skip_whitespace(word + length);
 
     return word;
@@ -634 +708 @@
     if (!name)
         return NULL;
-
+    /* TODO: use index_in_str_array() */
     for (i = 0; i < af->n_methods; i++) {
         if (strcmp(af->method[i].name, name) == 0) {
@@ -643 +717 @@
 }
 
-static const llist_t *find_list_string(const llist_t *list, const char *string)
-{
-    if (string == NULL)
-        return NULL;
-
-    while (list) {
-        if (strcmp(list->data, string) == 0) {
-            return list;
-        }
-        list = list->link;
-    }
-    return NULL;
-}
-
 static struct interfaces_file_t *read_interfaces(const char *filename)
 {
+    /* Let's try to be compatible.
+     *
+     * "man 5 interfaces" says:
+     * Lines starting with "#" are ignored. Note that end-of-line
+     * comments are NOT supported, comments must be on a line of their own.
+     * A line may be extended across multiple lines by making
+     * the last character a backslash.
+     *
+     * Seen elsewhere in example config file:
+     * A first non-blank "#" character makes the rest of the line
+     * be ignored. Blank lines are ignored. Lines may be indented freely.
+     * A "\" character at the very end of the line indicates the next line
+     * should be treated as a continuation of the current one.
+     */
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
     struct mapping_defn_t *currmap = NULL;
@@ -665 +739 @@
     struct interfaces_file_t *defn;
     FILE *f;
-    char *firstword;
     char *buf;
-
+    char *first_word;
+    char *rest_of_line;
     enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 
-    defn = xzalloc(sizeof(struct interfaces_file_t));
-
-    f = xfopen(filename, "r");
-
-    while ((buf = xmalloc_getline(f)) != NULL) {
-        char *buf_ptr = buf;
-
-        firstword = next_word(&buf_ptr);
-        if (firstword == NULL) {
+    defn = xzalloc(sizeof(*defn));
+    f = xfopen_for_read(filename);
+
+    while ((buf = xmalloc_fgetline(f)) != NULL) {
+#if ENABLE_DESKTOP
+        /* Trailing "\" concatenates lines */
+        char *p;
+        while ((p = last_char_is(buf, '\\')) != NULL) {
+            *p = '\0';
+            rest_of_line = xmalloc_fgetline(f);
+            if (!rest_of_line)
+                break;
+            p = xasprintf("%s%s", buf, rest_of_line);
             free(buf);
-            continue;   /* blank line */
-        }
-
-        if (strcmp(firstword, "mapping") == 0) {
+            free(rest_of_line);
+            buf = p;
+        }
+#endif
+        rest_of_line = buf;
+        first_word = next_word(&rest_of_line);
+        if (!first_word || *first_word == '#') {
+            free(buf);
+            continue; /* blank/comment line */
+        }
+
+        if (strcmp(first_word, "mapping") == 0) {
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
-            currmap = xzalloc(sizeof(struct mapping_defn_t));
-
-            while ((firstword = next_word(&buf_ptr)) != NULL) {
-                if (currmap->max_matches == currmap->n_matches) {
-                    currmap->max_matches = currmap->max_matches * 2 + 1;
-                    currmap->match = xrealloc(currmap->match, sizeof(currmap->match) * currmap->max_matches);
-                }
-
-                currmap->match[currmap->n_matches++] = xstrdup(firstword);
-            }
-            currmap->max_mappings = 0;
-            currmap->n_mappings = 0;
-            currmap->mapping = NULL;
-            currmap->script = NULL;
+            currmap = xzalloc(sizeof(*currmap));
+
+            while ((first_word = next_word(&rest_of_line)) != NULL) {
+                currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
+                currmap->match[currmap->n_matches++] = xstrdup(first_word);
+            }
+            /*currmap->max_mappings = 0; - done by xzalloc */
+            /*currmap->n_mappings = 0;*/
+            /*currmap->mapping = NULL;*/
+            /*currmap->script = NULL;*/
             {
                 struct mapping_defn_t **where = &defn->mappings;
@@ -705 +787 @@
                 }
                 *where = currmap;
-                currmap->next = NULL;
+                /*currmap->next = NULL;*/
             }
             debug_noise("Added mapping\n");
 #endif
             currently_processing = MAPPING;
-        } else if (strcmp(firstword, "iface") == 0) {
+        } else if (strcmp(first_word, "iface") == 0) {
             static const struct address_family_t *const addr_fams[] = {
 #if ENABLE_FEATURE_IFUPDOWN_IPV4
@@ -720 +802 @@
                 NULL
             };
-
             char *iface_name;
             char *address_family_name;
@@ -726 +807 @@
             llist_t *iface_list;
 
-            currif = xzalloc(sizeof(struct interface_defn_t));
-            iface_name = next_word(&buf_ptr);
-            address_family_name = next_word(&buf_ptr);
-            method_name = next_word(&buf_ptr);
-
-            if (buf_ptr == NULL) {
-                bb_error_msg("too few parameters for line \"%s\"", buf);
-                return NULL;
-            }
+            currif = xzalloc(sizeof(*currif));
+            iface_name = next_word(&rest_of_line);
+            address_family_name = next_word(&rest_of_line);
+            method_name = next_word(&rest_of_line);
+
+            if (method_name == NULL)
+                bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 
             /* ship any trailing whitespace */
-            buf_ptr = skip_whitespace(buf_ptr);
-
-            if (buf_ptr[0] != '\0') {
-                bb_error_msg("too many parameters \"%s\"", buf);
-                return NULL;
-            }
+            rest_of_line = skip_whitespace(rest_of_line);
+
+            if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
+                bb_error_msg_and_die("too many parameters \"%s\"", buf);
 
             currif->iface = xstrdup(iface_name);
 
             currif->address_family = get_address_family(addr_fams, address_family_name);
-            if (!currif->address_family) {
-                bb_error_msg("unknown address type \"%s\"", address_family_name);
-                return NULL;
-            }
+            if (!currif->address_family)
+                bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 
             currif->method = get_method(currif->address_family, method_name);
-            if (!currif->method) {
-                bb_error_msg("unknown method \"%s\"", method_name);
-                return NULL;
-            }
+            if (!currif->method)
+                bb_error_msg_and_die("unknown method \"%s\"", method_name);
 
             for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
-                if ((strcmp(tmp->iface, currif->iface) == 0) &&
-                    (tmp->address_family == currif->address_family)) {
-                    bb_error_msg("duplicate interface \"%s\"", tmp->iface);
-                    return NULL;
+                if ((strcmp(tmp->iface, currif->iface) == 0)
+                 && (tmp->address_family == currif->address_family)
+                ) {
+                    bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
                 }
             }
@@ -770 +843 @@
             debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
             currently_processing = IFACE;
-        } else if (strcmp(firstword, "auto") == 0) {
-            while ((firstword = next_word(&buf_ptr)) != NULL) {
+        } else if (strcmp(first_word, "auto") == 0) {
+            while ((first_word = next_word(&rest_of_line)) != NULL) {
 
                 /* Check the interface isnt already listed */
-                if (find_list_string(defn->autointerfaces, firstword)) {
+                if (llist_find_str(defn->autointerfaces, first_word)) {
                     bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
                 }
 
                 /* Add the interface to the list */
-                llist_add_to_end(&(defn->autointerfaces), xstrdup(firstword));
-                debug_noise("\nauto %s\n", firstword);
+                llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
+                debug_noise("\nauto %s\n", first_word);
             }
             currently_processing = NONE;
@@ -786 +859 @@
             switch (currently_processing) {
             case IFACE:
-                {
+                if (rest_of_line[0] == '\0')
+                    bb_error_msg_and_die("option with empty value \"%s\"", buf);
+
+                if (strcmp(first_word, "up") != 0
+                 && strcmp(first_word, "down") != 0
+                 && strcmp(first_word, "pre-up") != 0
+                 && strcmp(first_word, "post-down") != 0
+                ) {
                     int i;
-
-                    if (strlen(buf_ptr) == 0) {
-                        bb_error_msg("option with empty value \"%s\"", buf);
-                        return NULL;
+                    for (i = 0; i < currif->n_options; i++) {
+                        if (strcmp(currif->option[i].name, first_word) == 0)
+                            bb_error_msg_and_die("duplicate option \"%s\"", buf);
                     }
-
-                    if (strcmp(firstword, "up") != 0
-                            && strcmp(firstword, "down") != 0
-                            && strcmp(firstword, "pre-up") != 0
-                            && strcmp(firstword, "post-down") != 0) {
-                        for (i = 0; i < currif->n_options; i++) {
-                            if (strcmp(currif->option[i].name, firstword) == 0) {
-                                bb_error_msg("duplicate option \"%s\"", buf);
-                                return NULL;
-                            }
-                        }
-                    }
                 }
                 if (currif->n_options >= currif->max_options) {
-                    struct variable_t *opt;
-
-                    currif->max_options = currif->max_options + 10;
-                    opt = xrealloc(currif->option, sizeof(*opt) * currif->max_options);
-                    currif->option = opt;
-                }
-                currif->option[currif->n_options].name = xstrdup(firstword);
-                currif->option[currif->n_options].value = xstrdup(buf_ptr);
-                if (!currif->option[currif->n_options].name) {
-                    perror(filename);
-                    return NULL;
-                }
-                if (!currif->option[currif->n_options].value) {
-                    perror(filename);
-                    return NULL;
-                }
-                debug_noise("\t%s=%s\n", currif->option[currif->n_options].name,
-                        currif->option[currif->n_options].value);
+                    currif->max_options += 10;
+                    currif->option = xrealloc(currif->option,
+                        sizeof(*currif->option) * currif->max_options);
+                }
+                debug_noise("\t%s=%s\n", first_word, rest_of_line);
+                currif->option[currif->n_options].name = xstrdup(first_word);
+                currif->option[currif->n_options].value = xstrdup(rest_of_line);
                 currif->n_options++;
                 break;
             case MAPPING:
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
-                if (strcmp(firstword, "script") == 0) {
-                    if (currmap->script != NULL) {
-                        bb_error_msg("duplicate script in mapping \"%s\"", buf);
-                        return NULL;
-                    } else {
-                        currmap->script = xstrdup(next_word(&buf_ptr));
+                if (strcmp(first_word, "script") == 0) {
+                    if (currmap->script != NULL)
+                        bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
+                    currmap->script = xstrdup(next_word(&rest_of_line));
+                } else if (strcmp(first_word, "map") == 0) {
+                    if (currmap->n_mappings >= currmap->max_mappings) {
+                        currmap->max_mappings = currmap->max_mappings * 2 + 1;
+                        currmap->mapping = xrealloc(currmap->mapping,
+                            sizeof(char *) * currmap->max_mappings);
                     }
-                } else if (strcmp(firstword, "map") == 0) {
-                    if (currmap->max_mappings == currmap->n_mappings) {
-                        currmap->max_mappings = currmap->max_mappings * 2 + 1;
-                        currmap->mapping = xrealloc(currmap->mapping, sizeof(char *) * currmap->max_mappings);
-                    }
-                    currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&buf_ptr));
+                    currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
                     currmap->n_mappings++;
                 } else {
-                    bb_error_msg("misplaced option \"%s\"", buf);
-                    return NULL;
+                    bb_error_msg_and_die("misplaced option \"%s\"", buf);
                 }
 #endif
@@ -851 +904 @@
             case NONE:
             default:
-                bb_error_msg("misplaced option \"%s\"", buf);
-                return NULL;
+                bb_error_msg_and_die("misplaced option \"%s\"", buf);
             }
         }
         free(buf);
-    }
+    } /* while (fgets) */
+
     if (ferror(f) != 0) {
         /* ferror does NOT set errno! */
@@ -869 +922 @@
 {
     char *result;
-    char *here;
-    char *there;
+    char *dst;
+    char *src;
+    char c;
 
     result = xasprintf(format, name, value);
 
-    for (here = there = result; *there != '=' && *there; there++) {
-        if (*there == '-')
-            *there = '_';
-        if (isalpha(*there))
-            *there = toupper(*there);
-
-        if (isalnum(*there) || *there == '_') {
-            *here = *there;
-            here++;
-        }
-    }
-    memmove(here, there, strlen(there) + 1);
+    for (dst = src = result; (c = *src) != '=' && c; src++) {
+        if (c == '-')
+            c = '_';
+        if (c >= 'a' && c <= 'z')
+            c -= ('a' - 'A');
+        if (isalnum(c) || c == '_')
+            *dst++ = c;
+    }
+    overlapping_strcpy(dst, src);
 
     return result;
@@ -892 +943 @@
 static void set_environ(struct interface_defn_t *iface, const char *mode)
 {
-    char **environend;
     int i;
-    const int n_env_entries = iface->n_options + 5;
-    char **ppch;
-
-    if (my_environ != NULL) {
-        for (ppch = my_environ; *ppch; ppch++) {
-            free(*ppch);
-            *ppch = NULL;
-        }
-        free(my_environ);
-    }
-    my_environ = xzalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
-    environend = my_environ;
+    char **pp;
+
+    if (G.my_environ != NULL) {
+        for (pp = G.my_environ; *pp; pp++) {
+            free(*pp);
+        }
+        free(G.my_environ);
+    }
+
+    /* note: last element will stay NULL: */
+    G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 6));
+    pp = G.my_environ;
 
     for (i = 0; i < iface->n_options; i++) {
@@ -915 +965 @@
             continue;
         }
-        *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
-    }
-
-    *(environend++) = setlocalenv("%s=%s", "IFACE", iface->iface);
-    *(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
-    *(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
-    *(environend++) = setlocalenv("%s=%s", "MODE", mode);
-    *(environend++) = setlocalenv("%s=%s", "PATH", startup_PATH);
+        *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
+    }
+
+    *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
+    *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
+    *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
+    *pp++ = setlocalenv("%s=%s", "MODE", mode);
+    if (G.startup_PATH)
+        *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
 }
 
@@ -934 +985 @@
         int status;
 
-        fflush(NULL);
-        child = fork();
+        fflush_all();
+        child = vfork();
         switch (child) {
         case -1: /* failure */
             return 0;
         case 0: /* child */
-            execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, NULL, my_environ);
-            exit(127);
-        }
-        waitpid(child, &status, 0);
+            execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, (char *) NULL, G.my_environ);
+            _exit(127);
+        }
+        safe_waitpid(child, &status, 0);
         if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
             return 0;
@@ -994 +1045 @@
 
 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
-static int popen2(FILE **in, FILE **out, char *command, ...)
-{
-    va_list ap;
-    char *argv[11] = { command };
-    int argc;
-    int infd[2], outfd[2];
+static int popen2(FILE **in, FILE **out, char *command, char *param)
+{
+    char *argv[3] = { command, param, NULL };
+    struct fd_pair infd, outfd;
     pid_t pid;
 
-    argc = 1;
-    va_start(ap, command);
-    while ((argc < 10) && (argv[argc] = va_arg(ap, char *))) {
-        argc++;
-    }
-    argv[argc] = NULL;  /* make sure */
-    va_end(ap);
-
-    if (pipe(infd) != 0) {
-        return 0;
-    }
-
-    if (pipe(outfd) != 0) {
-        close(infd[0]);
-        close(infd[1]);
-        return 0;
-    }
-
-    fflush(NULL);
-    switch (pid = fork()) {
-    case -1:            /* failure */
-        close(infd[0]);
-        close(infd[1]);
-        close(outfd[0]);
-        close(outfd[1]);
-        return 0;
-    case 0:         /* child */
-        dup2(infd[0], 0);
-        dup2(outfd[1], 1);
-        close(infd[0]);
-        close(infd[1]);
-        close(outfd[0]);
-        close(outfd[1]);
-        BB_EXECVP(command, argv);
-        exit(127);
-    default:            /* parent */
-        *in = fdopen(infd[1], "w");
-        *out = fdopen(outfd[0], "r");
-        close(infd[0]);
-        close(outfd[1]);
-        return pid;
-    }
-    /* unreached */
-}
-
-static char *run_mapping(char *physical, struct mapping_defn_t * map)
+    xpiped_pair(infd);
+    xpiped_pair(outfd);
+
+    fflush_all();
+    pid = xvfork();
+
+    if (pid == 0) {
+        /* Child */
+        /* NB: close _first_, then move fds! */
+        close(infd.wr);
+        close(outfd.rd);
+        xmove_fd(infd.rd, 0);
+        xmove_fd(outfd.wr, 1);
+        BB_EXECVP_or_die(argv);
+    }
+    /* parent */
+    close(infd.rd);
+    close(outfd.wr);
+    *in = xfdopen_for_write(infd.wr);
+    *out = xfdopen_for_read(outfd.rd);
+    return pid;
+}
+
+static char *run_mapping(char *physical, struct mapping_defn_t *map)
 {
     FILE *in, *out;
@@ -1055 +1082 @@
     char *logical = xstrdup(physical);
 
-    /* Run the mapping script. */
-    pid = popen2(&in, &out, map->script, physical, NULL);
-
-    /* popen2() returns 0 on failure. */
-    if (pid == 0)
-        return logical;
+    /* Run the mapping script. Never fails. */
+    pid = popen2(&in, &out, map->script, physical);
 
     /* Write mappings to stdin of mapping script. */
@@ -1067 +1090 @@
     }
     fclose(in);
-    waitpid(pid, &status, 0);
+    safe_waitpid(pid, &status, 0);
 
     if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
@@ -1073 +1096 @@
          * grab a line of output and use that as the name of the
          * logical interface. */
-        char *new_logical = xmalloc(MAX_INTERFACE_LENGTH);
-
-        if (fgets(new_logical, MAX_INTERFACE_LENGTH, out)) {
+        char *new_logical = xmalloc_fgetline(out);
+
+        if (new_logical) {
             /* If we are able to read a line of output from the script,
              * remove any trailing whitespace and use this value
@@ -1086 +1109 @@
             free(logical);
             logical = new_logical;
-        } else {
-            /* If we are UNABLE to read a line of output, discard our
-             * freshly allocated memory. */
-            free(new_logical);
         }
     }
@@ -1101 +1120 @@
 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
 {
-    unsigned short iface_len = strlen(iface);
+    unsigned iface_len = strlen(iface);
     llist_t *search = state_list;
 
     while (search) {
         if ((strncmp(search->data, iface, iface_len) == 0)
-         && (search->data[iface_len] == '=')) {
+         && (search->data[iface_len] == '=')
+        ) {
             return search;
         }
@@ -1118 +1138 @@
 {
     llist_t *state_list = NULL;
-    FILE *state_fp = fopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "r");
+    FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
 
     if (state_fp) {
@@ -1134 +1154 @@
 
 
-int ifupdown_main(int argc, char **argv);
-int ifupdown_main(int argc, char **argv)
-{
-    int (*cmds)(struct interface_defn_t *) = NULL;
+int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int ifupdown_main(int argc UNUSED_PARAM, char **argv)
+{
+    int (*cmds)(struct interface_defn_t *);
     struct interfaces_file_t *defn;
     llist_t *target_list = NULL;
@@ -1143 +1163 @@
     bool any_failures = 0;
 
+    INIT_G();
+
+    G.startup_PATH = getenv("PATH");
+
     cmds = iface_down;
     if (applet_name[2] == 'u') {
@@ -1150 +1174 @@
 
     getopt32(argv, OPTION_STR, &interfaces);
-    if (argc - optind > 0) {
+    argv += optind;
+    if (argv[0]) {
         if (DO_ALL) bb_show_usage();
     } else {
@@ -1159 +1184 @@
     defn = read_interfaces(interfaces);
     debug_noise("\ndone reading %s\n\n", interfaces);
-
-    if (!defn) {
-        return EXIT_FAILURE;
-    }
-
-    startup_PATH = getenv("PATH");
-    if (!startup_PATH) startup_PATH = "";
 
     /* Create a list of interfaces to work on */
@@ -1171 +1189 @@
         target_list = defn->autointerfaces;
     } else {
-        llist_add_to_end(&target_list, argv[optind]);
+        llist_add_to_end(&target_list, argv[0]);
     }
 
@@ -1182 +1200 @@
         char *pch;
         bool okay = 0;
-        unsigned cmds_ret;
+        int cmds_ret;
 
         iface = xstrdup(target_list->data);
@@ -1260 +1278 @@
         }
         if (VERBOSE) {
-            puts("");
+            bb_putchar('\n');
         }
 
@@ -1288 +1306 @@
 
             /* Actually write the new state */
-            state_fp = xfopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "w");
+            state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
             state = state_list;
             while (state) {