1 files changed, 133 insertions, 0 deletions
diff --git a/src/network/tc/tc-util.c b/src/network/tc/tc-util.c
new file mode 100644
index 0000000..3781182
--- /dev/null
+++ b/src/network/tc/tc-util.c
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright © 2019 VMware, Inc. */
+
+#include "alloc-util.h"
+#include "extract-word.h"
+#include "fileio.h"
+#include "parse-util.h"
+#include "percent-util.h"
+#include "tc-util.h"
+#include "time-util.h"
+
+int tc_init(double *ret_ticks_in_usec, uint32_t *ret_hz) {
+        static double ticks_in_usec = -1;
+        static uint32_t hz;
+
+        if (ticks_in_usec < 0) {
+                uint32_t clock_resolution, ticks_to_usec, usec_to_ticks;
+                _cleanup_free_ char *line = NULL;
+                double clock_factor;
+                int r;
+
+                r = read_one_line_file("/proc/net/psched", &line);
+                if (r < 0)
+                        return r;
+
+                r = sscanf(line, "%08x%08x%08x%08x", &ticks_to_usec, &usec_to_ticks, &clock_resolution, &hz);
+                if (r < 4)
+                        return -EIO;
+
+                clock_factor = (double) clock_resolution / USEC_PER_SEC;
+                ticks_in_usec = (double) ticks_to_usec / usec_to_ticks * clock_factor;
+        }
+
+        if (ret_ticks_in_usec)
+                *ret_ticks_in_usec = ticks_in_usec;
+        if (ret_hz)
+                *ret_hz = hz;
+
+        return 0;
+}
+
+int tc_time_to_tick(usec_t t, uint32_t *ret) {
+        double ticks_in_usec;
+        usec_t a;
+        int r;
+
+        assert(ret);
+
+        r = tc_init(&ticks_in_usec, NULL);
+        if (r < 0)
+                return r;
+
+        a = t * ticks_in_usec;
+        if (a > UINT32_MAX)
+                return -ERANGE;
+
+        *ret = a;
+        return 0;
+}
+
+int parse_tc_percent(const char *s, uint32_t *ret_fraction) {
+        int r;
+
+        assert(s);
+        assert(ret_fraction);
+
+        r = parse_permyriad(s);
+        if (r < 0)
+                return r;
+
+        *ret_fraction = (double) r / 10000 * UINT32_MAX;
+        return 0;
+}
+
+int tc_transmit_time(uint64_t rate, uint32_t size, uint32_t *ret) {
+        return tc_time_to_tick(USEC_PER_SEC * ((double)size / (double)rate), ret);
+}
+
+int tc_fill_ratespec_and_table(struct tc_ratespec *rate, uint32_t *rtab, uint32_t mtu) {
+        uint32_t cell_log = 0;
+        int r;
+
+        if (mtu == 0)
+                mtu = 2047;
+
+        while ((mtu >> cell_log) > 255)
+                cell_log++;
+
+        for (size_t i = 0; i < 256; i++) {
+                uint32_t sz;
+
+                sz = (i + 1) << cell_log;
+                if (sz < rate->mpu)
+                        sz = rate->mpu;
+                r = tc_transmit_time(rate->rate, sz, &rtab[i]);
+                if (r < 0)
+                        return r;
+        }
+
+        rate->cell_align = -1;
+        rate->cell_log = cell_log;
+        rate->linklayer = TC_LINKLAYER_ETHERNET;
+        return 0;
+}
+
+int parse_handle(const char *t, uint32_t *ret) {
+        _cleanup_free_ char *word = NULL;
+        uint16_t major, minor;
+        int r;
+
+        assert(t);
+        assert(ret);
+
+        /* Extract the major number. */
+        r = extract_first_word(&t, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+        if (!t)
+                return -EINVAL;
+
+        r = safe_atou16_full(word, 16, &major);
+        if (r < 0)
+                return r;
+
+        r = safe_atou16_full(t, 16, &minor);
+        if (r < 0)
+                return r;
+
+        *ret = ((uint32_t) major << 16) | minor;
+        return 0;
+}