1 files changed, 93 insertions, 0 deletions
diff --git a/src/common/impl/sysctl.c b/src/common/impl/sysctl.c
new file mode 100644
index 0000000..5974698
--- /dev/null
+++ b/src/common/impl/sysctl.c
@@ -0,0 +1,93 @@
+#include "common/sysctl.h"
+
+#include <stdlib.h>
+
+#ifdef __OpenBSD__
+const char* ffSysctlGetString(int mib1, int mib2, FFstrbuf* result) {
+    size_t neededLength;
+    if (sysctl((int[]) { mib1, mib2 }, 2, NULL, &neededLength, NULL, 0) != 0 || neededLength == 1) { // neededLength is 1 for empty strings, because of the null terminator
+        return "sysctl() length query failed";
+    }
+
+    ffStrbufEnsureFree(result, (uint32_t) neededLength - 1);
+
+    if (sysctl((int[]) { mib1, mib2 }, 2, result->chars + result->length, &neededLength, NULL, 0) != 0) {
+        return "sysctl() failed to retrieve string data";
+    }
+
+    result->length += (uint32_t) neededLength - 1;
+    result->chars[result->length] = '\0';
+
+    return NULL;
+}
+
+int ffSysctlGetInt(int mib1, int mib2, int defaultValue) {
+    int result;
+    size_t neededLength = sizeof(result);
+    if (sysctl((int[]) { mib1, mib2 }, 2, &result, &neededLength, NULL, 0) != 0) {
+        return defaultValue;
+    }
+    return result;
+}
+
+int64_t ffSysctlGetInt64(int mib1, int mib2, int64_t defaultValue) {
+    int64_t result;
+    size_t neededLength = sizeof(result);
+    if (sysctl((int[]) { mib1, mib2 }, 2, &result, &neededLength, NULL, 0) != 0) {
+        return defaultValue;
+    }
+    return result;
+}
+#else
+const char* ffSysctlGetString(const char* propName, FFstrbuf* result) {
+    size_t neededLength;
+    if (sysctlbyname(propName, NULL, &neededLength, NULL, 0) != 0 || neededLength == 1) { // neededLength is 1 for empty strings, because of the null terminator
+        return "sysctlbyname() failed";
+    }
+
+    ffStrbufEnsureFree(result, (uint32_t) neededLength - 1);
+
+    if (sysctlbyname(propName, result->chars + result->length, &neededLength, NULL, 0) != 0) {
+        return "sysctlbyname() failed to retrieve string data";
+    }
+
+    result->length += (uint32_t) neededLength - 1;
+
+    result->chars[result->length] = '\0';
+
+    return NULL;
+}
+
+int ffSysctlGetInt(const char* propName, int defaultValue) {
+    int result;
+    size_t neededLength = sizeof(result);
+    if (sysctlbyname(propName, &result, &neededLength, NULL, 0) != 0) {
+        return defaultValue;
+    }
+    return result;
+}
+
+int64_t ffSysctlGetInt64(const char* propName, int64_t defaultValue) {
+    int64_t result;
+    size_t neededLength = sizeof(result);
+    if (sysctlbyname(propName, &result, &neededLength, NULL, 0) != 0) {
+        return defaultValue;
+    }
+    return result;
+}
+#endif // OpenBSD
+
+void* ffSysctlGetData(int* request, u_int requestLength, size_t* resultLength) {
+    if (sysctl(request, requestLength, NULL, resultLength, NULL, 0) != 0) {
+        return NULL;
+    }
+
+    void* data = malloc(*resultLength);
+
+    if (sysctl(request, requestLength, data, resultLength, NULL, 0) != 0) {
+        free(data);
+        return NULL;
+    }
+
+    return data;
+}