Improved environment-query logic.

svn path=/trunk/; revision=2452

diff --git a/env.c b/env.c
index dd6755d405e630937c29ef9d168d55eba6a84baa..efa1173819e9850256b1fe7fa83b01d48d27bc43 100644 (file)
--- a/env.c
+++ b/env.c
@@ -33,30 +33,53 @@ extern char *program_name;
 void envquery(int argc, char **argv)
 /* set up basic stuff from the environment (including the rc file name) */
 {
-    struct passwd *pw;
+    struct passwd by_name, by_uid, *pwp;
 
-    if ((program_name = strrchr(argv[0], '/')) != NULL)
-       ++program_name;
-    else
-       program_name = argv[0];
+    if (!(user = getenv("LOGNAME")))
+       user = getenv("USER");
 
-    if ((pw = getpwuid(getuid())) != NULL)
-    {
-       user = pw->pw_name;
-       home = pw->pw_dir;
-    }
-    else if ((home = getenv("HOME")))
-    {
-       if ((user = getenv("LOGNAME")) == (char *)NULL || user[0] == '\0')
-           user = getenv("USER");
-    }
-    else
+    if (!(pwp = getpwuid(getuid())))
     {
        fprintf(stderr,
-               _("%s: can't find your name and home directory!\n"),
+               _("%s: You don't exist.  Go away.\n"),
                program_name);
        exit(PS_UNDEFINED);
     }
+    else
+    {
+       memcpy(&by_uid, pwp, sizeof(struct passwd));
+       if (!user)
+           pwp = &by_uid;
+       else if ((pwp = getpwnam(user)))
+       {
+           /*
+            * This logic is needed to handle gracefully the possibility
+            * that multiple names might be mapped to one UID
+            */
+           memcpy(&by_name, pwp, sizeof(struct passwd));
+
+           if (by_name.pw_uid == by_uid.pw_uid)
+               pwp = &by_name;
+           else
+               pwp = &by_uid;
+       }
+       else
+       {
+           fprintf(stderr,
+                   _("%s: can't find your name and home directory!\n"),
+                   program_name);
+           exit(PS_UNDEFINED);
+       }
+       user = xstrdup(pwp->pw_name);
+    }
+
+    if (!(home = getenv("HOME")))
+       home = pwp->pw_dir;
+
+    if ((program_name = strrchr(argv[0], '/')) != NULL)
+       ++program_name;
+    else
+       program_name = argv[0];
 
 #define RCFILE_NAME    ".fetchmailrc"
     rcfile = (char *) xmalloc(strlen(home)+strlen(RCFILE_NAME)+2);