New API to retrieve disk stats in Linux

sysdeps/linux/Makefile.am

@@ -4,7 +4,7 @@ noinst_LTLIBRARIES		= libgtop_sysdeps-2.0.la libgtop_sysdeps_suid-2.0.la
 
 EXTRA_DIST			= procmap_smaps.gperf procmap_smaps.c
 
-libgtop_sysdeps_2_0_la_SOURCES	= open.c close.c cpu.c mem.c swap.c \
+libgtop_sysdeps_2_0_la_SOURCES	= open.c close.c cpu.c disk.c mem.c swap.c \
 				  uptime.c loadavg.c shm_limits.c msg_limits.c \
 				  sem_limits.c proclist.c procstate.c procuid.c \
 				  proctime.c procmem.c procsignal.c prockernel.c \

sysdeps/linux/disk.c

@@ -0,0 +1,96 @@
+/* Copyright (C) 1998-99 Martin Baulig
+   This file is part of LibGTop 1.0.
+
+   Contributed by James Dominic P. Guana <guana.histark@gmail.com>, May 2020.
+
+   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/error.h>
+#include <glibtop/disk.h>
+
+#include "glibtop_private.h"
+
+static const unsigned long _glibtop_sysdeps_disk =
+(1L << GLIBTOP_XDISK_SECTORS_READ) + (1L << GLIBTOP_XDISK_TIME_READ) +
+(1L << GLIBTOP_XDISK_SECTORS_WRITE) + (1L << GLIBTOP_XDISK_TIME_WRITE);
+
+/* Init function. */
+
+void
+_glibtop_init_disk_s (glibtop *server)
+{
+	server->sysdeps.disk = _glibtop_sysdeps_disk;
+}
+
+/* Provides information about disk usage. */
+
+#define FILENAME	"/proc/diskstats" //kernel reports sectors by 512 bytes even for AF 4kn
+#define STAT_BUFSIZ     81920
+
+void
+glibtop_get_disk_s (glibtop *server, glibtop_disk *buf)
+{
+	char buffer [STAT_BUFSIZ], *p;
+	int i;
+
+	memset (buf, 0, sizeof (glibtop_disk));
+
+	file_to_buffer(server, buffer, sizeof buffer, FILENAME);
+
+	/*
+	 * GLOBAL
+	 */
+
+	p = buffer;	/* "disk" */
+
+	/*
+	 * PER DISK
+	 */
+
+	for (i = 0; i <= server->ndisk; i++) {
+
+        p = skip_multiple_token(p,2);
+
+        // skip if disk is the raw device
+        if(!check_alphanumeric_word(p)){
+
+		    p = skip_line(p); /* move to ^ */
+            p = skip_multiple_token(p,2);
+
+        }
+
+		if (!check_disk_line_warn(server, p, i))
+			break;
+
+        p = skip_token(p); /* prev xdisk_name */
+        p = skip_token(p); /* prev xdisk_reads_completed */
+        p = skip_token(p); /* prev xdisk_reads_merged */
+
+		buf->xdisk_sectors_read [i] = strtoull (p, &p, 0);
+		buf->xdisk_time_read [i] = strtoull (p, &p, 0);
+
+        p = skip_token(p); /* prev xdisk_writes_completed */
+        p = skip_token(p); /* prev xdisk_writes_merged */
+
+		buf->xdisk_sectors_write  [i] = strtoull (p, &p, 0);
+		buf->xdisk_time_write [i] = strtoull (p, &p, 0);
+
+        p = skip_line(p); /* move to ^ */
+
+	}
+}

sysdeps/linux/glibtop_private.c

@@ -57,6 +57,24 @@ skip_token (const char *p)
 }
 
 
+int
+check_alphanumeric_word (const char *p)
+{
+	int test = 0;
+	p = next_token(p);
+	while (*p && !g_ascii_isspace(*p)) {
+		if(g_ascii_isalpha(*p)){
+			test = 0;
+		}else if(g_ascii_isdigit(*p)){
+			test = 1;
+		}
+		p++;
+	};
+	p = next_token(p);
+	return test;
+}
+
+
 /*
  * Read functions
  */

sysdeps/linux/glibtop_private.h

@@ -61,6 +61,9 @@ skip_line (const char *p)
 	return (char *) (*p ? p+1 : p);
 }
 
+int
+check_alphanumeric_word (const char *p);
+
 /*
  * Smart strtoul which handles binary suffixes
  * e.g: get_scaled("Size: 32 kB", "Size:") == 32768

sysdeps/linux/glibtop_server.h

@@ -23,6 +23,7 @@
 #define __LINUX__GLIBTOP_SERVER_H__
 
 #define GLIBTOP_SUID_CPU		0
+#define GLIBTOP_SUID_DISK		0
 #define GLIBTOP_SUID_MEM		0
 #define GLIBTOP_SUID_SWAP		0
 #define GLIBTOP_SUID_UPTIME		0