(mmh)

This patch adds the files lib/sysfs.h and lib/sysfs.c, beginning with a rewrite
of the sysfs detection code (using libsyfs).  In the process, I replaced two
poorly named globals with better names, and moved them to sysfs.c.  The sysfs
detection now happens very early during library init, rather than later.

The long term plan is for the two global variables to disappear anyway, as
everything to do with sysfs should get moved into lib/sysfs.c.


git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@3093 7894878c-1315-0410-8ee3-d5d059ff63e0

lib/proc.c

@@ -29,6 +29,7 @@
 #include "general.h"
 #include <limits.h>
 #include <dirent.h>
+#include "sysfs.h"
 
 /* OK, this proves one thing: if there are too many chips detected, we get in
    trouble. The limit is around 4096/sizeof(struct sensors_chip_data), which
@@ -42,9 +43,6 @@ static char buf[BUF_LEN];
 
 static int sensors_get_chip_id(sensors_chip_name name);
 
-int foundsysfs=0;
-char sysfsmount[NAME_MAX];
-
 static int getsysname(const sensors_chip_feature *feature, char *sysname,
 	int *sysmag, char *altsysname);
 
@@ -85,7 +83,7 @@ static int sensors_read_one_sysfs_chip(char *name, char *dirname, char *id)
 
 	/* Find out if ISA or not */
 	sprintf(name, "%s/class/i2c-adapter/i2c-%d/device/name",
-		sysfsmount, entry.name.bus);
+		sensors_sysfs_mount, entry.name.bus);
 	if ((f = fopen(name, "r")) != NULL) {
 		if (fgets(x, 5, f) != NULL
 		 && !strncmp(x, "ISA ", 4))
@@ -103,7 +101,6 @@ int sensors_read_proc_chips(void)
 {
 	struct dirent *de;
 	DIR *dir;
-	FILE *f;
 	char sysfs[NAME_MAX], n[NAME_MAX];
 	char dirname[NAME_MAX];
 	int res;
@@ -114,26 +111,11 @@ int sensors_read_proc_chips(void)
 	sensors_proc_chips_entry entry;
 	int lineno;
 
-	/* First figure out where sysfs was mounted */
-	if ((f = fopen("/proc/mounts", "r")) == NULL)
+	if (!sensors_found_sysfs)
 		goto proc;
-	while (fgets(n, NAME_MAX, f)) {
-		char *fstype = dirname; /* alias to keep the code readable */
-
-		if (sscanf(n, "%*[^ ] %[^ ] %[^ ] %*s\n", sysfsmount, fstype)
-				== 2 && !strcasecmp(fstype, "sysfs")) {
-			foundsysfs++;
-			break;
-		}
-	}
-	fclose(f);
-	if (!foundsysfs) {
-		memset(sysfsmount, '\0', sizeof(sysfsmount));
-		goto proc;
-	}
 
 	/* Try /sys/class/hwmon first (Linux 2.6.14 and up) */
-	strncpy(sysfs, sysfsmount, sizeof(sysfs) - 1);
+	strncpy(sysfs, sensors_sysfs_mount, sizeof(sysfs) - 1);
 	sysfs[sizeof(sysfs) - 1] = '\0';
 	strncat(sysfs, "/class/hwmon", sizeof(sysfs) - strlen(sysfs) - 1);
 
@@ -181,7 +163,7 @@ int sensors_read_proc_chips(void)
 
 oldsys:
 	/* Fall back to /sys/bus/i2c (Linux 2.5 to 2.6.13) */
-	strncpy(sysfs, sysfsmount, sizeof(sysfs) - 1);
+	strncpy(sysfs, sensors_sysfs_mount, sizeof(sysfs) - 1);
 	sysfs[sizeof(sysfs) - 1] = '\0';
 	strncat(sysfs, "/bus/i2c/devices", sizeof(sysfs) - strlen(sysfs) - 1);
 
@@ -242,9 +224,12 @@ int sensors_read_proc_bus(void)
 	char sysfs[NAME_MAX], n[NAME_MAX];
 	char dirname[NAME_MAX];
 
-	if(foundsysfs) {
-		strcpy(sysfs, sysfsmount);
-		strcat(sysfs, "/class/i2c-adapter");
+	if (sensors_found_sysfs) {
+		strncpy(sysfs, sensors_sysfs_mount, sizeof(sysfs) - 1);
+		sysfs[sizeof(sysfs) - 1] = 0;
+		strncat(sysfs, "/class/i2c-adapter",
+				sizeof(sysfs) - strlen(sysfs) - 1);
+
 		/* Then read from it */
 		dir = opendir(sysfs);
 		if (! dir)
@@ -352,12 +337,12 @@ int sensors_read_proc(sensors_chip_name name, int feature, double *value)
 	int buflen = BUF_LEN;
 	int mag;
 
-	if(!foundsysfs)
+	if (!sensors_found_sysfs)
 		if ((sysctl_name[2] = sensors_get_chip_id(name)) < 0)
 			return sysctl_name[2];
 	if (! (the_feature = sensors_lookup_feature_nr(name.prefix,feature)))
 		return -SENSORS_ERR_NO_ENTRY;
-	if(foundsysfs) {
+	if (sensors_found_sysfs) {
 		char n[NAME_MAX], altn[NAME_MAX];
 		FILE *f;
 		strcpy(n, name.busname);
@@ -394,12 +379,12 @@ int sensors_write_proc(sensors_chip_name name, int feature, double value)
 	int buflen = BUF_LEN;
 	int mag;
  
-	if(!foundsysfs)
+	if (!sensors_found_sysfs)
 		if ((sysctl_name[2] = sensors_get_chip_id(name)) < 0)
 			return sysctl_name[2];
 	if (! (the_feature = sensors_lookup_feature_nr(name.prefix,feature)))
 		return -SENSORS_ERR_NO_ENTRY;
-	if(foundsysfs) {
+	if (sensors_found_sysfs) {
 		char n[NAME_MAX], altn[NAME_MAX];
 		FILE *f;
 		strcpy(n, name.busname);