machine: Explain use of machine and tidy Linuxisms

The functions machine.h provides are deliberately using standard
functions from a base install of the operating system. This IS
intentional. I'd like to be able to modify and reuse this anywhere
without having to untangle additional dependencies from machine to
machine.

src/bin/system/machine.c

@@ -13,6 +13,7 @@
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
+
 #define _DEFAULT_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
@@ -76,7 +77,7 @@ _network_transfer_get_thread_cb(void *arg)
 
    system_network_transfer_get(usage);
 
-   return (void *)0;
+   return NULL;
 }
 
 void
@@ -86,13 +87,10 @@ system_info_all_free(Sys_Info *info)
    int i;
 
    for (i = 0; i < info->cpu_count; i++)
-     {
+     free(info->cores[i]);
-        free(info->cores[i]);
-     }
    free(info->cores);
 
-   for (i = 0; i < info->sensor_count; i++)
+   for (i = 0; i < info->sensor_count; i++) {
-     {
         snsr = info->sensors[i];
         if (snsr->name)
           free(snsr->name);
@@ -101,8 +99,7 @@ system_info_all_free(Sys_Info *info)
    if (info->sensors)
      free(info->sensors);
 
-   for (i = 0; i < info->power.battery_count; i++)
+   for (i = 0; i < info->power.battery_count; i++) {
-     {
         if (info->power.batteries[i]->name)
           free(info->power.batteries[i]->name);
 #if defined(__OpenBSD__)

src/bin/system/machine.h

@@ -1,6 +1,12 @@
 #ifndef __MACHINE_H__
 #define __MACHINE_H__
 
+/* All functions and data types implementing these APIs have no additional
+ * system dependencies deliberately.
+ *
+ * See machine.c and the files includes in machine/ sub directory.
+ */
+
 #include <stdint.h>
 #include <stdbool.h>
 
@@ -13,15 +19,15 @@ typedef struct
 
 typedef struct
 {
-   unsigned long long total;
+   uint64_t total;
-   unsigned long long used;
+   uint64_t used;
-   unsigned long long cached;
+   uint64_t cached;
-   unsigned long long buffered;
+   uint64_t buffered;
-   unsigned long long shared;
+   uint64_t shared;
-   unsigned long long swap_total;
+   uint64_t swap_total;
-   unsigned long long swap_used;
+   uint64_t swap_used;
 
-   unsigned long long zfs_arc_used;
+   uint64_t zfs_arc_used;
 } meminfo_t;
 
 typedef struct
@@ -63,11 +69,12 @@ struct Sys_Info
 {
    int           cpu_count;
    cpu_core_t  **cores;
+
    meminfo_t     memory;
    power_t       power;
 
    int           sensor_count;
-   sensor_t     **sensors;
+   sensor_t    **sensors;
 
    network_t     network_usage;
 };

src/bin/system/machine/machine.bogox

@@ -15,6 +15,9 @@
  */
 
 #if defined(__linux__)
+
+#include <stdarg.h>
+
 char *
 file_contents(const char *path)
 {
@@ -49,6 +52,20 @@ file_contents(const char *path)
    return buf;
 }
 
+char *
+strsli_printf(const char *fmt, ...)
+{
+   static char buf[4096];
+   va_list ap;
+
+   buf[0] = 0x00;
+   va_start(ap, fmt);
+   vsnprintf(buf, sizeof(buf), fmt, ap);
+   va_end(ap);
+
+   return buf;
+}
+
 #endif
 
 #if defined(__FreeBSD__) || defined(__DragonFly__)

src/bin/system/machine/sensors.bogox

@@ -71,7 +71,6 @@ system_sensors_thermal_get(int *sensor_count)
 #elif defined(__linux__)
    sensor_t *sensor;
    char *type, *value;
-   char path[PATH_MAX];
    struct dirent **names;
    int i, n;
 
@@ -84,10 +83,8 @@ system_sensors_thermal_get(int *sensor_count)
              free(names[i]);
              continue;
           }
-        snprintf(path, sizeof(path), "/sys/class/thermal/%s/type",
-                 names[i]->d_name);
 
-        type = file_contents(path);
+        type = file_contents(strsli_printf("/sys/class/thermal/%s/type", names[i]->d_name));
         if (type)
           {
              sensors =
@@ -95,11 +92,9 @@ system_sensors_thermal_get(int *sensor_count)
              sensors[(*sensor_count)++] =
                  sensor = calloc(1, sizeof(sensor_t));
 
-             sensor->name = strdup(type);
+             sensor->name = type;
-             snprintf(path, sizeof(path), "/sys/class/thermal/%s/temp",
-                      names[i]->d_name);
 
-             value = file_contents(path);
+             value = file_contents(strsli_printf("/sys/class/thermal/%s/temp", names[i]->d_name));
              if (!value)
                sensor->invalid = true;
              else
@@ -107,7 +102,6 @@ system_sensors_thermal_get(int *sensor_count)
                   sensor->value = (float)atoi(value) / 1000.0;
                   free(value);
                }
-             free(type);
           }
 
         free(names[i]);
@@ -180,7 +174,6 @@ _power_battery_count_get(power_t *power)
      }
 #elif defined(__linux__)
    char *type;
-   char path[PATH_MAX];
    struct dirent **names;
    int i, n, id;
 
@@ -188,10 +181,7 @@ _power_battery_count_get(power_t *power)
    if (n < 0) return power->battery_count;
 
    for (i = 0; i < n; i++) {
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s/type",
+        type = file_contents(strsli_printf("/sys/class/power_supply/%s/type", names[i]->d_name));
-                 names[i]->d_name);
-
-        type = file_contents(path);
         if (type)
           {
              if (!strncmp(type, "Battery", 7))
@@ -287,24 +277,20 @@ _battery_state_get(power_t *power)
    close(fd);
 
 #elif defined(__linux__)
-   char path[PATH_MAX];
+   const char *path;
    struct dirent *dh;
    struct stat st;
    DIR *dir;
    char *model, *vendor;
    char *buf, *naming = NULL;
-   int i = 0;
-   unsigned long charge_full = 0;
-   unsigned long charge_current = 0;
 
-   for (i = 0; i < power->battery_count; i++) {
+   for (int i = 0; i < power->battery_count; i++) {
         naming = NULL;
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s",
-                 power->batteries[i]->name);
 
-        if (stat(path, &st) < 0) continue;
+        path = strsli_printf("/sys/class/power_suppy/%s", power->batteries[i]->name);
-        if (S_ISLNK(st.st_mode)) continue;
+
-        if (!S_ISDIR(st.st_mode)) continue;
+        if (((stat(path, &st) < 0)) || (S_ISLNK(st.st_mode)) || (!S_ISDIR(st.st_mode)))
+          continue;
 
         dir = opendir(path);
         if (!dir) return;
@@ -324,34 +310,28 @@ _battery_state_get(power_t *power)
         if (!naming)
           continue;
 
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s/%s_full",
+        buf = file_contents(strsli_printf("/sys/class/power_supply/%s/%s_full",
-                 power->batteries[i]->name, naming);
+                            power->batteries[i]->name, naming));
-        buf = file_contents(path);
         if (buf)
           {
-             charge_full = atol(buf);
+             power->batteries[i]->charge_full = atol(buf);
              free(buf);
           }
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s/%s_now",
+        buf = file_contents(strsli_printf("/sys/class/power_supply/%s/%s_now",
-                 power->batteries[i]->name, naming);
+                            power->batteries[i]->name, naming));
-        buf = file_contents(path);
         if (buf)
           {
-             charge_current = atol(buf);
+             power->batteries[i]->charge_current = atol(buf);
              free(buf);
           }
 
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s/manufacturer",
+        vendor = file_contents(strsli_printf("/sys/class/power_supply/%s/manufacturer",
-                 power->batteries[i]->name);
+                               power->batteries[i]->name));
-        vendor = file_contents(path);
+        model = file_contents(strsli_printf("/sys/class/power_supply/%s/model_name",
-
+                              power->batteries[i]->name));
-        snprintf(path, sizeof(path), "/sys/class/power_supply/%s/model_name",
-                 power->batteries[i]->name);
-        model = file_contents(path);
 
         if (vendor && vendor[0] && model && model[0])
           {
-             char name[256];
              int len;
 
              len = strlen(vendor) - 1;
@@ -363,13 +343,8 @@ _battery_state_get(power_t *power)
                model[len] = '\0';
 
              free(power->batteries[i]->name);;
-             snprintf(name, sizeof(name), "%s %s", vendor, model);
+             power->batteries[i]->name = strdup(strsli_printf("%s %s", vendor, model));
-             power->batteries[i]->name = strdup(name);
           }
-
-        power->batteries[i]->charge_full = charge_full;
-        power->batteries[i]->charge_current = charge_current;
-
         if (model)
           free(model);
         if (vendor)
@@ -417,13 +392,12 @@ system_power_state_get(power_t *power)
      }
 #endif
 
-  _battery_state_get(power);
+   _battery_state_get(power);
 
    for (i = 0; i < power->battery_count; i++) {
-        double percent = 100 *
+        power->batteries[i]->percent = 100 *
            (power->batteries[i]->charge_current /
                                     power->batteries[i]->charge_full);
-        power->batteries[i]->percent = percent;
      }
 }