new cross-platform code to list processes. works on linux and freebsd

4 files changed, 198 insertions, 2 deletions

diff --git a/src/Makefile b/src/Makefile
index bacec4b..57be683 100755
--- a/src/Makefile
+++ b/src/Makefile
@@ -9,11 +9,14 @@ ifeq ($(UNAME), FreeBSD)
 LIBS+=-lkvm
 endif
 
-all::	$(TARGETS)
+all::	$(TARGETS) process_iterator.o
 
 cpulimit:	cpulimit.c $(LIBS)
 	$(CC) -o cpulimit cpulimit.c $(LIBS) $(CFLAGS)
 
+process_iterator.o: process_iterator.c process_iterator.h
+	$(CC) -c process_iterator.c $(CFLAGS)
+
 process.o: process.c process.h
 	$(CC) -c process.c $(CFLAGS)
 
diff --git a/src/process_iterator.c b/src/process_iterator.c
new file mode 100644
index 0000000..fd35952
--- /dev/null
+++ b/src/process_iterator.c
@@ -0,0 +1,121 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/procfs.h>
+
+#include "process_iterator.h"
+
+//TODO read this to port to other systems: http://www.steve.org.uk/Reference/Unix/faq_8.html#SEC85
+
+#ifdef __linux__
+
+int init_process_iterator(struct process_iterator *it) {
+	//open a directory stream to /proc directory
+	if ((it->dip = opendir("/proc")) == NULL) {
+		perror("opendir");
+		return -1;
+	}
+	return 0;
+}
+
+int read_next_process(struct process_iterator *it, struct process *p) {
+	char statfile[20];
+	char buffer[1024];
+	//read in from /proc and seek for process dirs
+	while ((it->dit = readdir(it->dip)) != NULL) {
+		if(strtok(it->dit->d_name, "0123456789") != NULL)
+			continue;
+		p->pid = atoi(it->dit->d_name);
+		//read stat file
+		sprintf(statfile, "/proc/%d/stat", p->pid);
+		FILE *fd = fopen(statfile, "r");
+		if (fd==NULL) return -1;
+		if (fgets(buffer, sizeof(buffer), fd)==NULL) {
+			fclose(fd);
+			return -1;
+		}
+		fclose(fd);
+		char *token = strtok(buffer, " ");
+		int i;
+		for (i=0; i<3; i++) token = strtok(NULL, " ");
+		p->ppid = atoi(token);
+		for (i=0; i<10; i++)
+			token = strtok(NULL, " ");
+		p->last_jiffies = atoi(token);
+		token = strtok(NULL, " ");
+		p->last_jiffies += atoi(token);
+		for (i=0; i<7; i++)
+			token = strtok(NULL, " ");
+		p->starttime = atoi(token);
+		break;
+		//read command line
+		char exefile[20];
+		sprintf(exefile,"/proc/%d/cmdline", p->pid);
+		fd = fopen(statfile, "r");
+		char buffer[1024];
+		if (fgets(buffer, sizeof(buffer), fd)==NULL) {
+			fclose(fd);
+			return -1;
+		}
+		fclose(fd);
+		sscanf(buffer, "%s", (char*)&p->command);
+	}
+	if (it->dit == NULL)
+	{
+		//end of processes
+		closedir(it->dip);
+		it->dip = NULL;
+		return -1;
+	}
+	return 0;
+}
+
+int close_process_iterator(struct process_iterator *it) {
+	if (it->dip != 0 && closedir(it->dip) == -1) {
+		perror("closedir");
+		return 1;
+	}
+	return 0;
+}
+
+#elif defined __APPLE__
+
+#elif defined __FreeBSD__
+
+#include <sys/sysctl.h>
+#include <sys/user.h>
+
+int init_process_iterator(struct process_iterator *it) {
+	char errbuf[_POSIX2_LINE_MAX];
+	/* Open the kvm interface, get a descriptor */
+	if ((it->kd = kvm_open(NULL, NULL, NULL, 0, errbuf)) == NULL) {
+		/* fprintf(stderr, "kvm_open: %s\n", errbuf); */
+		fprintf(stderr, "kvm_open: %s", errbuf);
+		return -1;
+	}
+	/* Get the list of processes. */
+	if ((it->procs = kvm_getprocs(it->kd, KERN_PROC_PROC, 0, &it->count)) == NULL) {
+		kvm_close(it->kd);
+		/* fprintf(stderr, "kvm_getprocs: %s\n", kvm_geterr(kd)); */
+		fprintf(stderr, "kvm_getprocs: %s", kvm_geterr(it->kd));
+		return -1;
+	}
+	kvm_close(it->kd);
+	it->i = 0;
+	return 0;
+}
+
+int read_next_process(struct process_iterator *it, struct process *p) {
+	if (it->i == it->count) return -1;
+	p->pid = it->procs[it->i].ki_pid;
+	p->ppid = it->procs[it->i].ki_ppid;
+	p->last_jiffies = it->procs[it->i].ki_runtime / 1000;
+	it->i++;
+	return 0;
+}
+
+int close_process_iterator(struct process_iterator *it) {
+	return 0;
+}
+
+#endif
diff --git a/src/process_iterator.h b/src/process_iterator.h
new file mode 100644
index 0000000..fc559d3
--- /dev/null
+++ b/src/process_iterator.h
@@ -0,0 +1,72 @@
+/**
+ *
+ * cpulimit - a cpu limiter for Linux
+ *
+ * Copyright (C) 2005-2012, by:  Angelo Marletta <marlonx80@hotmail.com>
+ *
+ * This program 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.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#ifndef __PROCESS_ITERATOR_H
+
+#define __PROCESS_ITERATOR_H
+
+#include <unistd.h>
+#include <limits.h>
+#include <dirent.h>
+
+#ifdef __FreeBSD__
+#include <kvm.h>
+#endif
+
+// process descriptor
+struct process {
+	//pid of the process
+	pid_t pid;
+	//pid of the process
+	pid_t ppid;
+	//start time
+	int starttime;
+	//total number of jiffies used by the process at time last_sample
+	int last_jiffies;
+	//actual cpu usage estimation (value in range 0-1)
+	double cpu_usage;
+	//1 if the process is zombie
+	int is_zombie;
+	//absolute path of the executable file
+	char command[PATH_MAX+1];
+};
+
+struct process_iterator {
+#ifdef __linux__
+	DIR *dip;
+	struct dirent *dit;
+#elif defined __APPLE__
+	struct kinfo_proc *procList;
+#elif defined __FreeBSD__
+	kvm_t *kd;
+	struct kinfo_proc *procs;
+	int count;
+	int i;
+#endif
+};
+
+int init_process_iterator(struct process_iterator *i);
+
+int read_next_process(struct process_iterator *i, struct process *p);
+
+int close_process_iterator(struct process_iterator *i);
+
+#endif
diff --git a/src/procutils.c b/src/procutils.c
index 19b7054..7367196 100644
--- a/src/procutils.c
+++ b/src/procutils.c
@@ -69,7 +69,7 @@ static pid_t getppid_of(pid_t pid)
 	get_proc_info(&p, pid);
 	return p.ppid;
 #elif defined __FreeBSD__
-	
+
 #endif
 }