Loadavg (Android): fix compiling

CMakeLists.txt

@@ -541,7 +541,7 @@ elseif(BSD)
         src/detection/lm/lm_linux.c
         src/detection/icons/icons_linux.c
         src/detection/libc/libc_bsd.c
-        src/detection/loadavg/loadavg_linux.c
+        src/detection/loadavg/loadavg_bsd.c
         src/detection/locale/locale_linux.c
         src/detection/localip/localip_linux.c
         src/detection/gamepad/gamepad_bsd.c
@@ -598,7 +598,7 @@ elseif(APPLE)
         src/detection/host/host_apple.c
         src/detection/icons/icons_nosupport.c
         src/detection/lm/lm_nosupport.c
-        src/detection/loadavg/loadavg_linux.c
+        src/detection/loadavg/loadavg_bsd.c
         src/detection/libc/libc_apple.c
         src/detection/locale/locale_linux.c
         src/detection/localip/localip_linux.c

src/detection/loadavg/loadavg_bsd.c

@@ -0,0 +1,8 @@
+#include "detection/loadavg/loadavg.h"
+
+#include <stdlib.h>
+
+const char* ffDetectLoadavg(double result[3])
+{
+    return getloadavg(result, 3) < 0 ? "getloadavg() failed" : NULL;
+}

src/detection/loadavg/loadavg_linux.c

@@ -1,8 +1,31 @@
 #include "detection/loadavg/loadavg.h"
+#include "common/io/io.h"
 
-#include <stdlib.h>
+#include <sys/sysinfo.h>
 
 const char* ffDetectLoadavg(double result[3])
 {
-    return getloadavg(result, 3) < 0 ? "getloadavg() failed" : NULL;
+    #ifndef __ANDROID__ // cat: /proc/loadavg: Permission denied
+
+    // Don't use syscall for container compatibility. #620
+    char buf[64];
+    ssize_t nRead = ffReadFileData("/proc/uptime", sizeof(buf) - 1, buf);
+    if (nRead > 0)
+    {
+        buf[nRead] = '\0';
+
+        if (sscanf(buf, "%lf %lf %lf", &result[0], &result[1], &result[2]) == 3)
+            return NULL;
+    }
+
+    #endif
+
+    // getloadavg requires higher ANDROID_API version
+    struct sysinfo si;
+    if (sysinfo(&si) < 0)
+        return "sysinfo() failed";
+
+    for (int i = 0; i < 3; i++)
+        result[i] = (double) si.loads[i] / (1 << SI_LOAD_SHIFT);
+    return NULL;
 }