ifupdown: stop emitting annoying/misleading error messages.

Patch by Gabriel Somlo <somlo at cmu.edu>

4 files changed, 74 insertions, 88 deletions

diff --git a/debianutils/which.c b/debianutils/which.c
index 583d94613..e83c752a1 100644
--- a/debianutils/which.c
+++ b/debianutils/which.c
@@ -3,6 +3,7 @@
  * Which implementation for busybox
  *
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu>
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  *
@@ -10,74 +11,33 @@
  */
 
 #include "busybox.h"
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/stat.h>
-
-
-static int is_executable_file(char *a, struct stat *b)
-{
-        return (!access(a,X_OK) && !stat(a, b) && S_ISREG(b->st_mode));
-}
 
 int which_main(int argc, char **argv)
 {
-        int status;
-        size_t i, count;
-        char *path_list, *p;
+        int status = EXIT_SUCCESS;
+        char *p;
 
         if (argc <= 1 || argv[1][0] == '-') {
                 bb_show_usage();
         }
-        argc--;
-
-        path_list = getenv("PATH");
-        if (path_list != NULL) {
-                count = 1;
-                p = path_list;
-                while ((p = strchr(p, ':')) != NULL) {
-                        *p++ = 0;
-                        count++;
-                }
-        } else {
-                path_list = "/bin\0/sbin\0/usr/bin\0/usr/sbin\0/usr/local/bin";
-                count = 5;
-        }
-
-        status = EXIT_SUCCESS;
-        while (argc-- > 0) {
-                struct stat stat_b;
-                char *buf;
 
+        while (--argc > 0) {
                 argv++;
-                buf = argv[0];
-
-                /* If filename is either absolute or contains slashes,
-                 * stat it */
-                if (strchr(buf, '/')) {
-                        if (is_executable_file(buf, &stat_b)) {
-                                puts(buf);
-                                goto next;
+                if (strchr(*argv, '/')) {
+                        if (execable_file(*argv)) {
+                                puts(*argv);
+                                continue;
                         }
                 } else {
-                        /* File doesn't contain slashes */
-                        p = path_list;
-                        for (i = 0; i < count; i++) {
-                                /* Empty component in PATH is treated as . */
-                                buf = concat_path_file(p[0] ? p : ".", argv[0]);
-                                if (is_executable_file(buf, &stat_b)) {
-                                        puts(buf);
-                                        free(buf);
-                                        goto next;
-                                }
-                                free(buf);
-                                p += strlen(p) + 1;
+                        p = find_execable(*argv);
+                        if (p) {
+                                puts(p);
+                                free(p);
+                                continue;
                         }
                 }
                 status = EXIT_FAILURE;
- next:          /* nothing */;
         }
+
         bb_fflush_stdout_and_exit(status);
 }
diff --git a/include/libbb.h b/include/libbb.h
index 1d26b0367..ac48411c0 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -430,6 +430,10 @@ char *last_char_is(const char *s, int c);
 
 char *fgets_str(FILE *file, const char *terminating_string);
 
+int execable_file(const char *name);
+char *find_execable(const char *filename);
+int exists_execable(const char *filename);
+
 extern USE_DESKTOP(long long) int uncompress(int fd_in, int fd_out);
 extern int inflate(int in, int out);
 
diff --git a/libbb/Kbuild b/libbb/Kbuild
index 4e992ef5b..27ed68c2c 100644
--- a/libbb/Kbuild
+++ b/libbb/Kbuild
@@ -28,7 +28,7 @@ lib-y:= \
         getopt32.o default_error_retval.o wfopen_input.o speed_table.o \
         perror_nomsg_and_die.o perror_nomsg.o skip_whitespace.o bb_askpass.o \
         warn_ignoring_args.o concat_subpath_file.o vfork_daemon_rexec.o \
-        bb_do_delay.o uuencode.o info_msg.o vinfo_msg.o
+        bb_do_delay.o uuencode.o info_msg.o vinfo_msg.o execable.o
 
 # conditionally compiled objects:
 lib-$(CONFIG_FEATURE_MOUNT_LOOP) += loop.o
diff --git a/networking/ifupdown.c b/networking/ifupdown.c
index f572b487d..c1dc1d35d 100644
--- a/networking/ifupdown.c
+++ b/networking/ifupdown.c
@@ -133,7 +133,7 @@ static int count_netmask_bits(char *dotted_quad)
 }
 #endif
 
-static void addstr(char **buf, size_t *len, size_t *pos, char *str, size_t str_length)
+static void addstr(char **buf, size_t *len, size_t *pos, const char *str, size_t str_length)
 {
         if (*pos + str_length >= *len) {
                 char *newbuf;
@@ -150,7 +150,7 @@ static void addstr(char **buf, size_t *len, size_t *pos, char *str, size_t str_l
         (*buf)[*pos] = '\0';
 }
 
-static int strncmpz(char *l, char *r, size_t llen)
+static int strncmpz(const char *l, const char *r, size_t llen)
 {
         int i = strncmp(l, r, llen);
 
@@ -161,7 +161,7 @@ static int strncmpz(char *l, char *r, size_t llen)
         }
 }
 
-static char *get_var(char *id, size_t idlen, struct interface_defn_t *ifd)
+static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
 {
         int i;
 
@@ -188,7 +188,7 @@ static char *get_var(char *id, size_t idlen, struct interface_defn_t *ifd)
         return NULL;
 }
 
-static char *parse(char *command, struct interface_defn_t *ifd)
+static char *parse(const char *command, struct interface_defn_t *ifd)
 {
 
         char *result = NULL;
@@ -294,7 +294,7 @@ static char *parse(char *command, struct interface_defn_t *ifd)
 }
 
 /* execute() returns 1 for success and 0 for failure */
-static int execute(char *command, struct interface_defn_t *ifd, execfn *exec)
+static int execute(const char *command, struct interface_defn_t *ifd, execfn *exec)
 {
         char *out;
         int ret;
@@ -449,43 +449,65 @@ static int static_down(struct interface_defn_t *ifd, execfn *exec)
         return ((result == 2) ? 2 : 0);
 }
 
-static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
+#ifndef CONFIG_APP_UDHCPC
+struct dhcp_client_t
 {
-        if (execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface% "
-                        "[[-H %hostname%]] [[-c %clientid%]] [[-s %script%]]", ifd, exec))
-                return 1;
-
-        /* 2006-09-30: The following are deprecated, and should eventually be
-         * removed. For non-busybox (i.e., other than udhcpc) clients, use
-         * 'iface foo inet manual' in /etc/network/interfaces, and supply
-         * start/stop commands explicitly via up/down. */
+        const char *name;
+        const char *startcmd;
+        const char *stopcmd;
+};
 
-        if (execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]",
-                        ifd, exec)) return 1;
-        if (execute("dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
-                        ifd, exec)) return 1;
-        if (execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] "
-                        "[[-l %leasetime%]] %iface%", ifd, exec)) return 1;
+static const struct dhcp_client_t ext_dhcp_clients[] = {
+        { "udhcpc",
+                "udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface% [[-H %hostname%]] [[-c %clientid%]] [[-s %script%]]",
+                "kill -TERM `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
+        },
+        { "pump",
+                "pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]",
+                "pump -i %iface% -k",
+        },
+        { "dhclient",
+                "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
+                "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
+        },
+        { "dhcpcd",
+                "dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] [[-l %leasetime%]] %iface%",
+                "dhcpcd -k %iface%",
+        },
+};
+#endif
 
+static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
+{
+#ifdef CONFIG_APP_UDHCPC
+        return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
+                        "-i %iface% [[-H %hostname%]] [[-c %clientid%]] [[-s %script%]]",
+                        ifd, exec);
+#else
+        int i, nclients = sizeof(ext_dhcp_clients) / sizeof(ext_dhcp_clients[0]);
+        for (i = 0; i < nclients; i++) {
+                if (exists_execable(ext_dhcp_clients[i].name))
+                        return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
+        }
+        bb_error_msg("no dhcp clients found");
         return 0;
+#endif
 }
 
 static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 {
-        if (execute("kill -TERM `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
-                        ifd, exec)) return 1;
-
-        /* 2006-09-30: The following are deprecated, and should eventually be
-         * removed. For non-busybox (i.e., other than udhcpc) clients, use
-         * 'iface foo inet manual' in /etc/network/interfaces, and supply
-         * start/stop commands explicitly via up/down. */
-
-        if (execute("pump -i %iface% -k", ifd, exec)) return 1;
-        if (execute("kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
-                        ifd, exec)) return 1;
-        if (execute("dhcpcd -k %iface%", ifd, exec)) return 1;
-
+#ifdef CONFIG_APP_UDHCPC
+        return execute("kill -TERM "
+                       "`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
+#else
+        int i, nclients = sizeof(ext_dhcp_clients) / sizeof(ext_dhcp_clients[0]);
+        for (i = 0; i < nclients; 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);
+#endif
 }
 
 static int manual_up_down(struct interface_defn_t *ifd, execfn *exec)