Comments on the pax patch?

[Svante Signell <svante.signell@telia.com>]

Hi,

Attached is a patch to make pax-20090728 build under GNU/Hurd. Function
calls changed are readlink()->xreadlink() (new, same as for psmisc) and
realpath()->canonicalize_file_name().

Comments?

Thanks!

diff -ur pax-20090728/file_subs.c pax-20090728.modified/file_subs.c
--- pax-20090728/file_subs.c	2009-07-28 17:38:28.000000000 +0000
+++ pax-20090728.modified/file_subs.c	2011-10-12 19:03:24.000000000 +0000
@@ -342,6 +342,29 @@
  *	0 if ok, -1 otherwise
  */
 
+char* xreadlink(const char *filename) {
+	int nchars, size = 128;
+	char *buffer;
+	if ((buffer=(char*)malloc(size)) == NULL) {
+		errno = ENOMEM;
+		return NULL;
+	}
+	while ((nchars = readlink(filename,buffer,size)) == size) {
+		size *= 2;
+		if ((buffer = (char*)realloc(buffer,size)) == NULL) {
+			errno = ENOMEM;
+			return NULL;
+		}
+	}
+	if (nchars < 0) {
+		free (buffer);
+		errno = EINVAL;
+		return NULL;
+	}
+	buffer[nchars]='\0';
+	return buffer;
+}
+
 int
 node_creat(ARCHD *arcn)
 {
@@ -351,9 +374,8 @@
 	int pass = 0;
 	mode_t file_mode;
 	struct stat sb;
-	char target[MAXPATHLEN];
+	char *target = NULL;
 	char *nm = arcn->name;
-	int len;
 
 	/*
 	 * create node based on type, if that fails try to unlink the node and
@@ -374,17 +396,16 @@
 			if (strcmp(NM_TAR, argv0) == 0 && Lflag) {
 				while (lstat(nm, &sb) == 0 &&
 				    S_ISLNK(sb.st_mode)) {
-					len = readlink(nm, target,
-					    sizeof target - 1);
-					if (len == -1) {
+					target = xreadlink(nm);
+					if (target == NULL) {
 						syswarn(0, errno,
 						   "cannot follow symlink %s in chain for %s",
 						    nm, arcn->name);
 						res = -1;
 						goto badlink;
 					}
-					target[len] = '\0';
 					nm = target;
+					free(target);
 				}
 			}
 			res = mkdir(nm, file_mode);
Only in pax-20090728.modified: file_subs.c~
diff -ur pax-20090728/tables.c pax-20090728.modified/tables.c
--- pax-20090728/tables.c	2009-07-28 17:38:28.000000000 +0000
+++ pax-20090728.modified/tables.c	2011-10-12 18:34:21.000000000 +0000
@@ -1126,17 +1126,18 @@
 add_dir(char *name, struct stat *psb, int frc_mode)
 {
 	DIRDATA *dblk;
-	char realname[MAXPATHLEN], *rp;
+	char *rp;
 
 	if (dirp == NULL)
 		return;
 
 	if (havechd && *name != '/') {
-		if ((rp = realpath(name, realname)) == NULL) {
+	  if ((rp = canonicalize_file_name(name)) == NULL) {
 			paxwarn(1, "Cannot canonicalize %s", name);
 			return;
 		}
 		name = rp;
+		free(rp);
 	}
 	if (dircnt == dirsize) {
 		dblk = realloc(dirp, 2 * dirsize * sizeof(DIRDATA));