/* Copyright (C) 1998-99 Martin Baulig

   This file is part of LibGTop 1.0.

   Contributed by Martin Baulig <martin@home-of-linux.org>, April 1998.

   LibGTop is free software; you can redistribute it and/or modify it

   under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 2 of the License,

   or (at your option) any later version.

   LibGTop is distributed in the hope that it will be useful, but WITHOUT

   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

   for more details.

   You should have received a copy of the GNU General Public License

   along with LibGTop; see the file COPYING. If not, write to the

   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

   Boston, MA 02110-1301, USA.

*/

#include <config.h>

#include <glibtop.h>

#include <glibtop/error.h>

#include <glibtop/procmem.h>

#include "glibtop_private.h"

static const unsigned long _glibtop_sysdeps_proc_mem =

(1L << GLIBTOP_PROC_MEM_SIZE) + (1L << GLIBTOP_PROC_MEM_RESIDENT) +

(1L << GLIBTOP_PROC_MEM_SHARE);

static const unsigned long _glibtop_sysdeps_proc_mem_pss =

(1L << GLIBTOP_PROC_MEM_RSS);

static unsigned long

get_pss(glibtop* server, pid_t pid)

{

	char filepath[128];

	FILE* smaps;

	char* line = NULL;

	size_t line_size = 0;

	unsigned long pss = 0;

	snprintf(filepath, sizeof filepath, "/proc/%u/smaps", (unsigned)pid);

	if (!(smaps = fopen(filepath, "r"))) {

		glibtop_error_io_r(server, "Cannot open %s", filepath);

		goto out;

	}

	while (getline(&line, &line_size, smaps) != -1) {

		if (strncmp(line, "Pss:", 4))

			continue;

		pss += get_scaled(line + 4, NULL);

	}

out:

	if (smaps)

		fclose(smaps);

	free(line);

	return pss;

}

/* Init function. */

void

_glibtop_init_proc_mem_s (glibtop *server)

{

	server->sysdeps.proc_mem = _glibtop_sysdeps_proc_mem;

	if (server->os_version_code >= LINUX_VERSION_CODE(2, 6, 25))

		server->sysdeps.proc_mem |= _glibtop_sysdeps_proc_mem_pss;

}

/* Provides detailed information about a process. */

void

glibtop_get_proc_mem_s (glibtop *server, glibtop_proc_mem *buf, pid_t pid)

{

	char buffer [BUFSIZ], *p;

	const size_t pagesize = getpagesize();

	memset (buf, 0, sizeof (glibtop_proc_mem));

	/* As of 2.6.24 in fs/proc/*.c

	   == rss vs. resident ==

	   stat/rss:

	   get_mm_rss where

	   #define get_mm_rss(mm)					\

		(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))

	   statm/resident:

	   *shared = get_mm_counter(mm, file_rss);

	   *resident = *shared + get_mm_counter(mm, anon_rss);

	   == vsize vs. size ==

	   stat/vsize:

	   task_vsize(mm) ... total_vm * pagesize

	   statm/size

	   mm->total_vm

	   =================

	   rss == resident

	   vsize == size

	   rss_lim is not implemented in statm, but there's limits which

		provides all limits

	   share is only implemented in statm

	*/

	if (proc_statm_to_buffer(buffer, sizeof buffer, pid))

		return;

	buf->size     = strtoull (buffer, &p, 0);

	buf->resident = strtoull (p, &p, 0);

	buf->share    = strtoull (p, &p, 0);

	buf->size     *= pagesize;

	buf->resident *= pagesize;

	buf->share    *= pagesize;

	/* dummy values */

	buf->vsize = buf->size;

	buf->rss_rlim = ~0;

	buf->flags |= _glibtop_sysdeps_proc_mem;

#if 0 

	/* FIXME: see previous comment */

	if (server->os_version_code >= LINUX_VERSION_CODE(2, 6, 25)) {

		buf->rss = get_pss(server, pid);

		buf->flags |= _glibtop_sysdeps_proc_mem_pss;

	}

#else

	buf->rss = buf->resident;

#endif

}