[PATCH] add seq file helpers from 2.5 (fwd)

[PATCH] add seq file helpers from 2.5 (fwd)

[Marcelo Tosatti]

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Viro,

I think you are the right person to review that.

Would you do me the favour?

---------- Forwarded message ----------
Date: Wed, 09 Jul 2003 20:16:54 -0400
From: Jeff Muizelaar <kernel@infidigm.net>
To: Marcelo Tosatti <marcelo@conectiva.com.br>
Subject: [PATCH] add seq file helpers from 2.5

Marcelo,

The attached patch adds the single_* helpers that have been in 2.5 since
May 2002, it also adds some missing includes that are in 2.5.

-Jeff

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diff -urN linux-2.4.21-bk1/fs/seq_file.c linux-2.4.21-bk1-seq-file-single/fs/seq_file.c
--- linux-2.4.21-bk1/fs/seq_file.c	2003-06-13 10:51:37.000000000 -0400
+++ linux-2.4.21-bk1-seq-file-single/fs/seq_file.c	2003-07-09 20:06:25.000000000 -0400
@@ -295,3 +295,45 @@
 	m->count = m->size;
 	return -1;
 }
+
+static void *single_start(struct seq_file *p, loff_t *pos)
+{
+	return NULL + (*pos == 0);
+}
+
+static void *single_next(struct seq_file *p, void *v, loff_t *pos)
+{
+	++*pos;
+	return NULL;
+}
+
+static void single_stop(struct seq_file *p, void *v)
+{
+}
+
+int single_open(struct file *file, int (*show)(struct seq_file *, void*), void *data)
+{
+	struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL);
+	int res = -ENOMEM;
+
+	if (op) {
+		op->start = single_start;
+		op->next = single_next;
+		op->stop = single_stop;
+		op->show = show;
+		res = seq_open(file, op);
+		if (!res)
+			((struct seq_file *)file->private_data)->private = data;
+		else
+			kfree(op);
+	}
+	return res;
+}
+
+int single_release(struct inode *inode, struct file *file)
+{
+	struct seq_operations *op = ((struct seq_file *)file->private_data)->op;
+	int res = seq_release(inode, file);
+	kfree(op);
+	return res;
+}
diff -urN linux-2.4.21-bk1/include/linux/seq_file.h linux-2.4.21-bk1-seq-file-single/include/linux/seq_file.h
--- linux-2.4.21-bk1/include/linux/seq_file.h	2002-08-02 20:39:45.000000000 -0400
+++ linux-2.4.21-bk1-seq-file-single/include/linux/seq_file.h	2003-07-06 08:57:25.000000000 -0400
@@ -2,7 +2,13 @@
 #define _LINUX_SEQ_FILE_H
 #ifdef __KERNEL__
 
+#include <linux/types.h>
+#include <linux/string.h>
+#include <asm/semaphore.h>
+
 struct seq_operations;
+struct file;
+struct inode;
 
 struct seq_file {
 	char *buf;
@@ -52,5 +58,8 @@
 int seq_printf(struct seq_file *, const char *, ...)
 	__attribute__ ((format (printf,2,3)));
 
+
+int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
+int single_release(struct inode *, struct file *);
 #endif
 #endif

Re: [PATCH] add seq file helpers from 2.5 (fwd)

[Randy.Dunlap]

Marcelo,

I didn't apply and build it, but it looks very much like the
patch that I sent to you on 2003-04-17 [1], to which you replied: [2]
  Saved to 2.4.22-pre folder.

I suggest that you apply it.  :)

~Randy

[1] http://marc.theaimsgroup.com/?l=linux-kernel&m=105061808602830&w=2
[2] http://marc.theaimsgroup.com/?l=linux-kernel&m=105094575909669&w=2


> Viro,
>
> I think you are the right person to review that.
>
> Would you do me the favour?
>
> ---------- Forwarded message ----------
> Date: Wed, 09 Jul 2003 20:16:54 -0400
> From: Jeff Muizelaar <kernel@infidigm.net>
> To: Marcelo Tosatti <marcelo@conectiva.com.br>
> Subject: [PATCH] add seq file helpers from 2.5
>
> Marcelo,
>
> The attached patch adds the single_* helpers that have been in 2.5 since May
> 2002, it also adds some missing includes that are in 2.5.
>
> -Jeff

Re: [PATCH] add seq file helpers from 2.5 (fwd)

[Chris Wright]

* Marcelo Tosatti (marcelo@conectiva.com.br) wrote:
> +int single_open(struct file *file, int (*show)(struct seq_file *, void*), void *data)
> +{
> +	struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL);
> +	int res = -ENOMEM;
> +
> +	if (op) {
> +		op->start = single_start;
> +		op->next = single_next;
> +		op->stop = single_stop;
> +		op->show = show;
> +		res = seq_open(file, op);

Any reason not to simply allocate static ops struct?  As in:

  static struct seq_operations single_ops = {
  	.start	= single_start;
	.next	= single_next;
	.stop	= single_stop;
	.show	= show;
  };

  int single_open()
  {
  	req = seq_open(file, &single_ops);
	...
  }

thanks,
-chris
-- 
Linux Security Modules     http://lsm.immunix.org     http://lsm.bkbits.net

Re: [PATCH] add seq file helpers from 2.5 (fwd)

[Chris Wright]

* Chris Wright (chris@wirex.com) wrote:
> * Marcelo Tosatti (marcelo@conectiva.com.br) wrote:
> > +int single_open(struct file *file, int (*show)(struct seq_file *, void*), void *data)
> > +{
> > +	struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL);
> > +	int res = -ENOMEM;
> > +
> > +	if (op) {
> > +		op->start = single_start;
> > +		op->next = single_next;
> > +		op->stop = single_stop;
> > +		op->show = show;
> > +		res = seq_open(file, op);
> 
> Any reason not to simply allocate static ops struct?  As in:

Bah, nevermind, I didn't look closely enough to see that show is
dynamic here (not to mention it is simple straight backport).  Sorry for
senseless noise ;-)

thanks,
-chris
-- 
Linux Security Modules     http://lsm.immunix.org     http://lsm.bkbits.net