[2773] in Release_Engineering
dm.c fix
daemon@ATHENA.MIT.EDU (Mark Rosenstein)
Thu Apr 16 23:55:37 1992
Date: Thu, 16 Apr 92 23:55:24 -0400
From: Mark Rosenstein <mar@MIT.EDU>
To: rel-eng@MIT.EDU
This is one of the "dialup derived fixes". It corrects the locking
protocol used with /etc/passwd. xlogin and /bin/login are already
accounted for. Next I'll check rlogind and cleanup. Anything else
we've written that may be this protocol wrong?
-Mark
*** /source/athena/athena.etc/xdm/dm/dm.c Sun Apr 5 16:41:09 1992
--- dm.c Thu Apr 16 23:41:36 1992
***************
*** 1031,1049 ****
if (!strcmp(login, "root")) return;
! while ((access(passwdtf, F_OK) == 0) && --count) {
! alarm(1);
! sigpause(0);
}
- if (count == 0) unlink(passwdtf);
-
oldfile = open(passwdf, O_RDONLY, 0);
if (oldfile < 0) return;
- newfile = open(passwdtf, O_WRONLY|O_CREAT|O_TRUNC, 0644);
- if (newfile < 0) {
- close(oldfile);
- return;
- }
/* process each line of file */
cc = read(oldfile, buf, BUFSIZ);
--- 1031,1052 ----
if (!strcmp(login, "root")) return;
! for (count = 0; count < 10; count++)
! if ((newfile = open(passwdtf, O_RDWR|O_CREAT|O_EXCL, 0644)) == -1 &&
! errno == EEXIST) {
! alarm(1);
! sigpause(0);
! } else
! break;
! if (newfile == -1) {
! if (count < 10)
! return(errno);
! else
! (void) unlink(passwdtf);
! return;
}
oldfile = open(passwdf, O_RDONLY, 0);
if (oldfile < 0) return;
/* process each line of file */
cc = read(oldfile, buf, BUFSIZ);
