Re: Bug#439036: chgrp builtin from zsh/files does not dereference symlinks (non-POSIX)

[Clint Adams <clint@xxxxxxx>]

On Tue, Aug 21, 2007 at 09:31:11PM +0200, Vincent Lefevre wrote:
> The chgrp builtin (and chown?) does not dereference symlinks, though
> POSIX requires symlinks to be dereferenced by default. Moreover, the
> behavior on symlinks is not documented in the zshmodules(1) man page.
> 
> There are still missing features (options) compared to POSIX chgrp,
> but I think that at least the default behavior and supported options
> should be the same as in POSIX.

I think this sabotages -s .  POSIX's -H, -L, -P options are still
missing.

Index: Doc/Zsh/mod_files.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/mod_files.yo,v
retrieving revision 1.2
diff -u -r1.2 mod_files.yo
--- Doc/Zsh/mod_files.yo	3 Jul 2007 17:06:04 -0000	1.2
+++ Doc/Zsh/mod_files.yo	21 Aug 2007 22:47:47 -0000
@@ -6,12 +6,12 @@
 
 startitem()
 findex(chgrp)
-item(tt(chgrp) [ tt(-Rs) ] var(group) var(filename) ...)(
+item(tt(chgrp) [ tt(-hRs) ] var(group) var(filename) ...)(
 Changes group of files specified.  This is equivalent to tt(chown) with
 a var(user-spec) argument of `tt(:)var(group)'.
 )
 findex(chown)
-item(tt(chown) [ tt(-Rs) ] var(user-spec) var(filename) ...)(
+item(tt(chown) [ tt(-hRs) ] var(user-spec) var(filename) ...)(
 Changes ownership and group of files specified.
 
 The var(user-spec) can be in four forms:
@@ -33,6 +33,9 @@
 appropriate) or a decimal user ID (group ID).  Interpretation as a name
 takes precedence, if there is an all-numeric username (or group name).
 
+If the target is a symbolic link, the tt(-h) option causes tt(chown) to set
+the ownership of the link instead of its target.
+
 The tt(-R) option causes tt(chown) to recursively descend into directories,
 changing the ownership of all files in the directory after
 changing the ownership of the directory itself.
Index: Src/Modules/files.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/Modules/files.c,v
retrieving revision 1.17
diff -u -r1.17 files.c
--- Src/Modules/files.c	6 Jul 2007 21:52:40 -0000	1.17
+++ Src/Modules/files.c	21 Aug 2007 22:47:48 -0000
@@ -593,6 +593,19 @@
 {
     struct chownmagic *chm = magic;
 
+    if(chown(rp, chm->uid, chm->gid)) {
+	zwarnnam(chm->nam, "%s: %e", arg, errno);
+	return 1;
+    }
+    return 0;
+}
+
+/**/
+static int
+chown_dolchown(char *arg, char *rp, UNUSED(struct stat const *sp), void *magic)
+{
+    struct chownmagic *chm = magic;
+
     if(lchown(rp, chm->uid, chm->gid)) {
 	zwarnnam(chm->nam, "%s: %e", arg, errno);
 	return 1;
@@ -600,6 +613,7 @@
     return 0;
 }
 
+
 /**/
 static unsigned long getnumeric(char *p, int *errp)
 {
@@ -684,7 +698,8 @@
     }
     free(uspec);
     return recursivecmd(nam, 0, OPT_ISSET(ops,'R'), OPT_ISSET(ops,'s'),
-	args + 1, chown_dochown, recurse_donothing, chown_dochown, &chm);
+	args + 1, OPT_ISSET(ops, 'h') ? chown_dolchown : chown_dochown, recurse_donothing,
+	OPT_ISSET(ops, 'h') ? chown_dolchown : chown_dochown, &chm);
 }
 
 /* module paraphernalia */
@@ -696,8 +711,8 @@
 #endif
 
 static struct builtin bintab[] = {
-    BUILTIN("chgrp", 0, bin_chown, 2, -1, BIN_CHGRP, "Rs",    NULL),
-    BUILTIN("chown", 0, bin_chown, 2, -1, BIN_CHOWN, "Rs",    NULL),
+    BUILTIN("chgrp", 0, bin_chown, 2, -1, BIN_CHGRP, "hRs",    NULL),
+    BUILTIN("chown", 0, bin_chown, 2, -1, BIN_CHOWN, "hRs",    NULL),
     BUILTIN("ln",    0, bin_ln,    1, -1, BIN_LN,    LN_OPTS, NULL),
     BUILTIN("mkdir", 0, bin_mkdir, 1, -1, 0,         "pm:",   NULL),
     BUILTIN("mv",    0, bin_ln,    2, -1, BIN_MV,    "fi",    NULL),