Patch from Lars Kellogg-Stedman, lars at larsshack.org, to

make ifupdown's mapping function work as documented.

diff --git a/networking/ifupdown.c b/networking/ifupdown.c
index 6c79c20..5b37c3a 100644 (file)
--- a/networking/ifupdown.c
+++ b/networking/ifupdown.c
@@ -49,6 +49,9 @@
 #define EUNDEFVAR   10002
 #define EUNBALPER   10000
 
+#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
+#define MAX_INTERFACE_LENGTH 10
+#endif
 
 #if 0
 #define debug_noise(fmt, args...) printf(fmt, ## args)
@@ -1106,12 +1109,13 @@ static int popen2(FILE **in, FILE **out, char *command, ...)
        /* unreached */
 }
 
-static int run_mapping(char *physical, char *logical, int len, struct mapping_defn_t * map)
+static char * run_mapping(char *physical, char *logical, int len, struct mapping_defn_t * map)
 {
        FILE *in, *out;
        int i, status;
        pid_t pid;
 
+       char *new_logical = NULL;
 
        pid = popen2(&in, &out, map->script, physical, NULL);
        if (pid == 0) {
@@ -1123,16 +1127,18 @@ static int run_mapping(char *physical, char *logical, int len, struct mapping_de
        fclose(in);
        waitpid(pid, &status, 0);
        if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
-               if (fgets(logical, len, out)) {
-                       char *pch = logical + bb_strlen(logical) - 1;
+               new_logical = (char *)xmalloc(MAX_INTERFACE_LENGTH);
+
+               if (fgets(new_logical, MAX_INTERFACE_LENGTH, out)) {
+                       char *pch = new_logical + bb_strlen(new_logical) - 1;
 
-                       while (pch >= logical && isspace(*pch))
+                       while (pch >= new_logical && isspace(*pch))
                                *(pch--) = '\0';
                }
        }
        fclose(out);
 
-       return 1;
+       return new_logical ? new_logical : logical;
 }
 #endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
 
@@ -1318,7 +1324,7 @@ extern int ifupdown_main(int argc, char **argv)
                                        if (verbose) {
                                                printf("Running mapping script %s on %s\n", currmap->script, liface);
                                        }
-                                       run_mapping(iface, liface, sizeof(liface), currmap);
+                                       liface = run_mapping(iface, liface, sizeof(liface), currmap);
                                        break;
                                }
                        }