system: add seife's proc_tools

Origin commit data
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Branch: ni/coolstream
Commit: bb9313ebb3
Author: vanhofen <vanhofen@gmx.de>
Date: 2017-11-13 (Mon, 13 Nov 2017)

Origin message was:
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- system: add seife's proc_tools

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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/system/Makefile.am

@@ -37,6 +37,7 @@ libneutrino_system_a_SOURCES = \
 	localize.cpp \
 	helpers.cpp \
 	ping.cpp \
+	proc_tools.c \
 	settings.cpp \
 	stacktrace.cpp \
 	sysload.cpp \

src/system/proc_tools.c

@@ -0,0 +1,59 @@
+/*
+ * helper functions to interact with files, usually in the proc filesystem
+ *
+ * (C) 2012 Stefan Seyfried <seife@tuxboxcvs.slipkontur.de>
+ *
+ * License: GPLv2 or later
+ *
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <ctype.h>	/* isspace */
+#include <stdio.h>	/* sscanf */
+
+#include "proc_tools.h"
+
+int proc_put(const char *path, const char *value, const int len)
+{
+	int ret, ret2;
+	int pfd = open(path, O_WRONLY);
+	if (pfd < 0)
+		return pfd;
+	ret = write(pfd, value, len);
+	ret2 = close(pfd);
+	if (ret2 < 0)
+		return ret2;
+	return ret;
+}
+
+int proc_get(const char *path, char *value, const int len)
+{
+	int ret, ret2;
+	int pfd = open(path, O_RDONLY);
+	if (pfd < 0)
+		return pfd;
+	ret = read(pfd, value, len);
+	value[len-1] = '\0'; /* make sure string is terminated */
+	if (ret >= 0)
+	{
+		while (ret > 0 && isspace(value[ret-1]))
+			ret--;		/* remove trailing whitespace */
+		value[ret] = '\0';	/* terminate, even if ret = 0 */
+	}
+	ret2 = close(pfd);
+	if (ret2 < 0)
+		return ret2;
+	return ret;
+}
+
+unsigned int proc_get_hex(const char *path)
+{
+	unsigned int n, ret = 0;
+	char buf[16];
+	n = proc_get(path, buf, 16);
+	if (n > 0)
+		sscanf(buf, "%x", &ret);
+	return ret;
+}

src/system/proc_tools.h

@@ -0,0 +1,20 @@
+/*
+ * helper functions to interact with files, usually in the proc filesystem
+ *
+ * (C) 2012 Stefan Seyfried <seife@tuxboxcvs.slipkontur.de>
+ *
+ * License: GPLv2 or later
+ *
+ */
+#ifndef __PROC_TOOLS_H__
+#define __PROC_TOOLS_H__
+#ifdef __cplusplus
+extern "C" {
+#endif
+int proc_put(const char *path, const char *value, const int len);
+int proc_get(const char *path, char *value, const int len);
+unsigned int proc_get_hex(const char *path);
+#ifdef __cplusplus
+}
+#endif
+#endif