1 files changed, 81 insertions, 0 deletions
diff --git a/src/detection/netio/netio.c b/src/detection/netio/netio.c
new file mode 100644
index 0000000..c6b9da6
--- /dev/null
+++ b/src/detection/netio/netio.c
@@ -0,0 +1,81 @@
+#include "netio.h"
+
+#include "common/time.h"
+
+static FFlist ioCounters1;
+static uint64_t time1;
+
+void ffPrepareNetIO(FFNetIOOptions* options) {
+    if (options->detectTotal) {
+        return;
+    }
+
+    if (time1 != 0) {
+        return; // Already prepared
+    }
+
+    ffListInit(&ioCounters1);
+    ffNetIOGetIoCounters(&ioCounters1, options);
+    time1 = ffTimeGetNow();
+}
+
+const char* ffDetectNetIO(FFlist* result, FFNetIOOptions* options) {
+    const char* error = NULL;
+
+    if (options->detectTotal) {
+        error = ffNetIOGetIoCounters(result, options);
+        if (error) {
+            return error;
+        }
+        return NULL;
+    }
+
+    if (time1 == 0) {
+        ffListInit(&ioCounters1);
+        error = ffNetIOGetIoCounters(&ioCounters1, options);
+        if (error) {
+            return error;
+        }
+        time1 = ffTimeGetNow();
+    }
+
+    if (ioCounters1.length == 0) {
+        return "No network interfaces found";
+    }
+
+    uint64_t time2 = ffTimeGetNow();
+    while (time2 - time1 < options->waitTime) {
+        ffTimeSleep((uint32_t) (options->waitTime - (time2 - time1)));
+        time2 = ffTimeGetNow();
+    }
+
+    error = ffNetIOGetIoCounters(result, options);
+    if (error) {
+        return error;
+    }
+
+    if (result->length != ioCounters1.length) {
+        return "Different number of network interfaces. Network change?";
+    }
+
+    for (uint32_t i = 0; i < result->length; ++i) {
+        FFNetIOResult* icPrev = FF_LIST_GET(FFNetIOResult, ioCounters1, i);
+        FFNetIOResult* icCurr = FF_LIST_GET(FFNetIOResult, *result, i);
+        if (!ffStrbufEqual(&icPrev->name, &icCurr->name)) {
+            return "Network interface name changed";
+        }
+
+        static_assert(sizeof(FFNetIOResult) - offsetof(FFNetIOResult, txBytes) == sizeof(uint64_t) * 8, "Unexpected struct FFNetIOResult layout");
+        for (size_t off = offsetof(FFNetIOResult, txBytes); off < sizeof(FFNetIOResult); off += sizeof(uint64_t)) {
+            uint64_t* prevValue = (uint64_t*) ((uint8_t*) icPrev + off);
+            uint64_t* currValue = (uint64_t*) ((uint8_t*) icCurr + off);
+            uint64_t temp = *currValue;
+            *currValue -= *prevValue;
+            *currValue /= (time2 - time1) / 1000 /* seconds */;
+            *prevValue = temp;
+        }
+    }
+    time1 = time2;
+
+    return NULL;
+}