Use _SysErrorMsg() in the log message in various error conditions.

Change LogError() invocations to use _SysErrorMsg() where errno might be
set (and not clobbered by intermediate calls).  Also make LogError() the
first thing we do after an error condition in those cases.

Forward-ported by David Nusinow, Eugene Konev and Julien Cristau.

Signed-off-by: Alan Coopersmith <alan.coopersmith@sun.com>

3 files changed, 50 insertions, 31 deletions

diff --git a/auth.c b/auth.c
index d0ec294..38191f8 100644
--- a/auth.c
+++ b/auth.c
@@ -865,7 +865,8 @@ DefineSelf (int fd, FILE *file, Xauth *auth)
     int	len, ipfd;
 
     if ((ipfd = open ("/dev/ip", O_RDWR, 0 )) < 0)
-        LogError ("Getting interface configuration");
+        LogError ("cannot get interface configuration; cannot open /dev/ip: "
+		  "%s\n", _SysErrorMsg (errno));
 
     /* Indicate that we want to start at the begining */
     ifnet.ib_next = (struct ipb *) 1;
@@ -879,8 +880,9 @@ DefineSelf (int fd, FILE *file, Xauth *auth)
 
 	if (ioctl (ipfd, (int) I_STR, (char *) &str) < 0)
 	{
+	    LogError ("cannot get interface configuration; ioctl failed: %s\n",
+		      _SysErrorMsg (errno));
 	    close (ipfd);
-	    LogError ("Getting interface configuration");
 	}
 
 	ifaddr.ia_next = (struct in_ifaddr *) ifnet.if_addrlist;
@@ -891,8 +893,9 @@ DefineSelf (int fd, FILE *file, Xauth *auth)
 
 	if (ioctl (ipfd, (int) I_STR, (char *) &str) < 0)
 	{
+	    LogError ("cannot get interface configuration; ioctl failed: %s\n",
+		      _SysErrorMsg (errno));
 	    close (ipfd);
-	    LogError ("Getting interface configuration");
 	}
 
 	/*
@@ -1350,16 +1353,22 @@ SetUserAuthorization (struct display *d, struct verify_info *verify)
 	doneAddrs ();
 	fclose (new);
 	if (unlink (name) == -1)
-	    Debug ("unlink %s failed\n", name);
+	    if (errno != ENOENT)
+		LogError ("cannot remove old authorization file %s: %s\n",
+			  name, _SysErrorMsg (errno));
 	envname = name;
 	if (link (new_name, name) == -1) {
-	    Debug ("link failed %s %s\n", new_name, name);
-	    LogError ("Can't move authorization into place\n");
+	    LogError ("cannot link temporary authorization file %s to old "
+		      "location %s: %s\n", new_name, name,
+		      _SysErrorMsg (errno));
 	    setenv = 1;
 	    envname = new_name;
 	} else {
-	    Debug ("new is in place, go for it!\n");
-	    unlink (new_name);
+	    Debug ("authorization file %s successfully updated\n", name);
+	    if (unlink (new_name))
+		if (errno != ENOENT)
+		    LogError ("cannot remove new authorization file %s:"
+			      " %s\n", new_name, _SysErrorMsg (errno));
 	}
 	if (setenv) {
 	    verify->userEnviron = setEnv (verify->userEnviron,
@@ -1429,13 +1438,19 @@ RemoveUserAuthorization (struct display *d, struct verify_info *verify)
 	doneAddrs ();
 	fclose (new);
 	if (unlink (name) == -1)
-	    Debug ("unlink %s failed\n", name);
+	    if (errno != ENOENT)
+		LogError ("cannot remove new authorization file %s: %s\n",
+			  name, _SysErrorMsg (errno));
 	if (link (new_name, name) == -1) {
-	    Debug ("link failed %s %s\n", new_name, name);
-	    LogError ("Can't move authorization into place\n");
+	    LogError ("cannot link temporary authorization file %s to old "
+		      "location %s: %s\n", new_name, name,
+		      _SysErrorMsg (errno));
 	} else {
-	    Debug ("new is in place, go for it!\n");
-	    unlink (new_name);
+	    Debug ("authorization file %s successfully updated\n", name);
+	    if (unlink (new_name))
+		if (errno != ENOENT)
+		    LogError ("cannot remove new authorization file %s:"
+			      " %s\n", new_name, _SysErrorMsg (errno));
 	}
     }
     XauUnlockAuth (name);
diff --git a/session.c b/session.c
index b2c9294..5040d3b 100644
--- a/session.c
+++ b/session.c
@@ -607,20 +607,22 @@ StartClient (
 
 #ifndef AIXV3
 # ifndef HAS_SETUSERCONTEXT
-	if (setgid(verify->gid) < 0) {
-	    LogError ("setgid %d (user \"%s\") failed, errno=%d\n",
-		     verify->gid, name, errno);
+	if (setgid (verify->gid) < 0) {
+	    LogError ("setgid %d (user \"%s\") failed: %s\n",
+		      verify->gid, name, _SysErrorMsg (errno));
 	    return (0);
 	}
 #  if defined(BSD) && (BSD >= 199103)
-	if (setlogin(name) < 0) {
-	    LogError ("setlogin for \"%s\" failed, errno=%d", name, errno);
-	    return(0);
+	if (setlogin (name) < 0) {
+	    LogError ("setlogin for \"%s\" failed: %s\n",
+		      name, _SysErrorMsg (errno));
+	    return (0);
 	}
 #  endif
 #  ifndef QNX4
-	if (initgroups(name, verify->gid) < 0) {
-	    LogError ("initgroups for \"%s\" failed, errno=%d\n", name, errno);
+	if (initgroups (name, verify->gid) < 0) {
+	    LogError ("initgroups for \"%s\" failed: %s\n",
+		      name, _SysErrorMsg (errno));
 	    return (0);
 	}
 #  endif   /* QNX4 doesn't support multi-groups, no initgroups() */
@@ -649,8 +651,8 @@ StartClient (
 
 # ifndef HAS_SETUSERCONTEXT
 	if (setuid(verify->uid) < 0) {
-	    LogError ("setuid %d (user \"%s\") failed, errno=%d\n",
-		     verify->uid, name, errno);
+	    LogError ("setuid %d (user \"%s\") failed: %s\n",
+		      verify->uid, name, _SysErrorMsg (errno));
 	    return (0);
 	}
 # else /* HAS_SETUSERCONTEXT */
@@ -661,13 +663,14 @@ StartClient (
 	pwd = getpwnam(name);
 	if (pwd) {
 	    if (setusercontext(NULL, pwd, pwd->pw_uid, LOGIN_SETALL) < 0) {
-		LogError ("setusercontext for \"%s\" failed, errno=%d\n", name,
-		    errno);
+		LogError ("setusercontext for \"%s\" failed: %s\n",
+			  name, _SysErrorMsg (errno));
 		return (0);
 	    }
 	    endpwent();
 	} else {
-	    LogError ("getpwnam for \"%s\" failed, errno=%d\n", name, errno);
+	    LogError ("getpwnam for \"%s\" failed: %s\n",
+		      name, _SysErrorMsg (errno));
 	    return (0);
 	}
 # endif /* HAS_SETUSERCONTEXT */
@@ -677,8 +680,8 @@ StartClient (
 	 * audit classes, user limits, and umask.
 	 */
 	if (setpcred(name, NULL) == -1) {
-	    LogError ("setpcred for \"%s\" failed: %s\n", name,
-		      _SysErrorMsg (errno));
+	    LogError ("setpcred for \"%s\" failed: %s\n",
+		      name, _SysErrorMsg (errno));
 	    return (0);
 	}
 #endif /* AIXV3 */
diff --git a/socket.c b/socket.c
index 16d43d8..3f73ae4 100644
--- a/socket.c
+++ b/socket.c
@@ -71,7 +71,7 @@ CreateWellKnownSockets (void)
     Debug ("Created chooser socket %d\n", chooserFd);
     if (chooserFd == -1)
     {
-	LogError ("chooser socket creation failed, errno %d\n", errno);
+	LogError ("chooser socket creation failed: %s\n", _SysErrorMsg (errno));
 	return;
     }
     listen (chooserFd, 5);
@@ -149,14 +149,15 @@ CreateListeningSocket (struct sockaddr *sock_addr, int salen)
     fd = socket (sock_addr->sa_family, SOCK_DGRAM, 0);
 
     if (fd == -1) {
-	LogError ("XDMCP socket creation failed, errno %d\n", errno);
+	LogError ("XDMCP socket creation failed: %s\n", _SysErrorMsg (errno));
 	return fd;
     }
     RegisterCloseOnFork (fd);
 
     if (bind (fd, sock_addr, salen) == -1)
     {
-	LogError ("error %d binding socket address %d\n", errno, request_port);
+	LogError ("error binding socket address %d: %s\n", request_port,
+		  _SysErrorMsg (errno));
 	close (fd);
 	fd = -1;
 	return fd;