init.c bug merging environment

[Andreas Neuhaus]

Package: busybox
Version: cvs
Severity: normal

init.c tries to merge the existing environment (usually only TERM=linux when
booting a plain kernel) with the new settings (HOME,PATH,SHELL,USER). in
case you use linuxrc, there are already other environment settings added
(like PATH) which init.c isn't aware of. this results in a duplicate entry
for PATH in my case.

here's a patch for init.c that merges the two enviroments correctly. this
will create the child environment and only add  settings that init don't
sets itself.

Index: init.c
===================================================================
RCS file: /var/cvs/busybox/init.c,v
retrieving revision 1.126
diff -u -r1.126 init.c
--- init.c      2001/03/15 21:04:18     1.126
+++ init.c      2001/03/16 00:05:53
@@ -396,10 +396,10 @@

 static pid_t run(char *command, char *terminal, int get_enter)
 {
-       int i=0, j=0;
+       int i, j;
        int fd;
        pid_t pid;
-       char *tmpCmd;
+       char *tmpCmd, *s;
         char *cmd[255], *cmdpath;
        char buf[255];
        static const char press_enter[] =
@@ -410,18 +410,25 @@

                "\nPlease press Enter to activate this console. ";
        char *environment[MAXENV+1] = {
+               termType,
                "HOME=/",
                "PATH=/usr/bin:/bin:/usr/sbin:/sbin",
                "SHELL=/bin/sh",
-               termType,
-               "USER=root"
+               "USER=root",
+               NULL
        };

-       while (environment[i]) i++;
-       while ((environ[j]) && (i < MAXENV)) {
-               if (strncmp(environ[j], "TERM=", 5))
-                       environment[i++] = environ[j];
-               j++;
+       /* inherit environment to the child, merging our values -andy */
+       for (i=0; environ[i]; i++) {
+               for (j=0; environment[j]; j++) {
+                       s = strchr(environment[j], '=');
+                       if (!strncmp(environ[i], environment[j], s -
environment[j]))
+                               break;
+               }
+               if (!environment[j]) {
+                       environment[j++] = environ[i];
+                       environment[j] = NULL;
+               }
        }

        if ((pid = fork()) == 0) {


regards,
andreas neuhaus
--
Life could be so much easier if we could just look at the source code...
  .~.
  /V\    Andreas Neuhaus, FaStA Informatik FH-Dortmund
 // \\    Sonnenstr. 96, D-44139 Dortmund, Tel 0231/9112-734
/(   )\    System-Administration FaStA FH-Dortmund
^^-^^
 LINUX - Don't fear the penguin



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Received: (at 1135-done) by bugs.lineo.com; 3 Apr 2001 17:11:20 +0000