Format timestamps with RFC3339 (#124)

* Add support for printing timestamps as RFC3339

* Print stake lockup timestamps as timestamps

* Tweak format for human readability

libsol/include/sol/printer.h

@@ -36,4 +36,6 @@ int print_summary(
     size_t right_length
 );
 
+int print_timestamp(int64_t, char* out, size_t out_length);
+
 int encode_base58(const void *in, size_t length, char *out, size_t maxoutlen);

libsol/include/sol/transaction_summary.h

@@ -37,6 +37,7 @@ enum SummaryItemKind {
     SummaryItemHash,
     SummaryItemSizedString,
     SummaryItemString,
+    SummaryItemTimestamp,
 };
 
 typedef struct SummaryItem SummaryItem;
@@ -105,3 +106,8 @@ void summary_item_set_string(
     const char* title,
     const char* value
 );
+void summary_item_set_timestamp(
+    SummaryItem* item,
+    const char* title,
+    int64_t value
+);

libsol/printer.c

@@ -1,6 +1,7 @@
 #include <string.h>
 #include <limits.h>
 #include "os_error.h"
+#include "rfc3339.h"
 #include "sol/printer.h"
 #include "util.h"
 
@@ -217,3 +218,7 @@ int print_u64(uint64_t u64, char* out, size_t out_length) {
 
     return 0;
 }
+
+int print_timestamp(int64_t timestamp, char* out, size_t out_length) {
+    return rfc3339_format(out, out_length, timestamp);
+}

libsol/printer_test.c

@@ -104,13 +104,32 @@ void test_print_u64() {
     assert(print_u64(0, NULL, 0) == 1);
 }
 
+void test_print_timestamp() {
+#define RFC3339_MAX (4 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1)
+    char out[RFC3339_MAX];
+    int64_t unix_epoch = 0;
+    const char* expect_unix_epoch = "1970-01-01 00:00:00";
+
+    assert(print_timestamp(unix_epoch, out, sizeof(out)) == 0);
+    assert_string_equal(out, expect_unix_epoch);
+
+    int64_t now = 1588374349;
+    const char* expect_now = "2020-05-01 23:05:49";
+
+    assert(print_timestamp(now, out, sizeof(out)) == 0);
+    assert_string_equal(out, expect_now);
+
+    assert(print_timestamp(0, out, sizeof(out) - 1) == 1);
+}
+
 int main() {
     test_print_amount();
     test_print_sized_string();
     test_print_string();
     test_print_summary();
     test_print_i64();
     test_print_u64();
+    test_print_timestamp();
 
     printf("passed\n");
     return 0;

libsol/rfc3339.c

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2014 Christian Hansen <[email protected]>
+ * <https://github.com/chansen/c-timestamp>
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met: 
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution. 
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <stddef.h>
+#include "rfc3339.h"
+
+static const uint16_t DayOffset[13] = {
+    0, 306, 337, 0, 31, 61, 92, 122, 153, 184, 214, 245, 275
+};
+
+/* Rata Die algorithm by Peter Baum */
+
+static void
+rdn_to_ymd(uint32_t rdn, uint16_t *yp, uint16_t *mp, uint16_t *dp) {
+    uint32_t Z, H, A, B;
+    uint16_t y, m, d;
+
+    Z = rdn + 306;
+    H = 100 * Z - 25;
+    A = H / 3652425;
+    B = A - (A >> 2);
+    y = (100 * B + H) / 36525;
+    d = B + Z - (1461 * y >> 2);
+    m = (535 * d + 48950) >> 14;
+    if (m > 12)
+        y++, m -= 12;
+
+    *yp = y;
+    *mp = m;
+    *dp = d - DayOffset[m];
+}
+
+#define EPOCH INT64_C(62135683200)  /* 1970-01-01 00:00:00 */
+
+int rfc3339_format(char *dst, size_t len, int64_t seconds) {
+    unsigned char *p;
+    uint64_t sec;
+    uint32_t rdn, v;
+    uint16_t y, m, d;
+    size_t dlen;
+
+    dlen = sizeof("YYYY-MM-DD hh:mm:ss") - 1;
+    if (dlen >= len)
+        return 1;
+
+    sec = seconds + EPOCH;
+    rdn = sec / 86400;
+
+    rdn_to_ymd(rdn, &y, &m, &d);
+
+   /*
+    *           1
+    * 0123456789012345678
+    * YYYY-MM-DDThh:mm:ss
+    */
+    p = (unsigned char *)dst;
+    v = sec % 86400;
+    p[18] = '0' + (v % 10); v /= 10;
+    p[17] = '0' + (v %  6); v /=  6;
+    p[16] = ':';
+    p[15] = '0' + (v % 10); v /= 10;
+    p[14] = '0' + (v %  6); v /=  6;
+    p[13] = ':';
+    p[12] = '0' + (v % 10); v /= 10;
+    p[11] = '0' + (v % 10);
+    p[10] = ' ';
+    p[ 9] = '0' + (d % 10); d /= 10;
+    p[ 8] = '0' + (d % 10);
+    p[ 7] = '-';
+    p[ 6] = '0' + (m % 10); m /= 10;
+    p[ 5] = '0' + (m % 10);
+    p[ 4] = '-';
+    p[ 3] = '0' + (y % 10); y /= 10;
+    p[ 2] = '0' + (y % 10); y /= 10;
+    p[ 1] = '0' + (y % 10); y /= 10;
+    p[ 0] = '0' + (y % 10);
+    p += 19;
+
+    *p = 0;
+    return 0;
+}
+

libsol/rfc3339.h

@@ -0,0 +1,5 @@
+#pragma once
+
+#include <stdint.h>
+
+int rfc3339_format(char *dst, size_t len, int64_t seconds);

libsol/stake_instruction.c

@@ -382,7 +382,11 @@ static int print_stake_set_lockup_info(
     enum StakeLockupPresent present = info->lockup.present;
     if (present & StakeLockupHasTimestamp) {
         item = transaction_summary_general_item();
-        summary_item_set_i64(item, "Lockup time", info->lockup.unix_timestamp);
+        summary_item_set_timestamp(
+            item,
+            "Lockup time",
+            info->lockup.unix_timestamp
+        );
     }
 
     if (present & StakeLockupHasEpoch) {
@@ -474,7 +478,11 @@ int print_stake_initialize_info(
     }
 
     item = transaction_summary_general_item();
-    summary_item_set_i64(item, "Lockup time", info->lockup.unix_timestamp);
+    summary_item_set_timestamp(
+        item,
+        "Lockup time",
+        info->lockup.unix_timestamp
+    );
 
     item = transaction_summary_general_item();
     summary_item_set_u64(item, "Lockup epoch", info->lockup.epoch);

libsol/transaction_summary.c

@@ -88,6 +88,16 @@ void summary_item_set_string(
     item->string = value;
 }
 
+void summary_item_set_timestamp(
+    SummaryItem* item,
+    const char* title,
+    int64_t value
+) {
+    item->kind = SummaryItemTimestamp;
+    item->title = title;
+    item->i64 = value;
+}
+
 typedef struct TransactionSummary {
     SummaryItem primary;
     SummaryItem fee_payer;
@@ -241,6 +251,13 @@ static int transaction_summary_update_display_for_item(
                 TEXT_BUFFER_LENGTH
             );
             break;
+        case SummaryItemTimestamp:
+            BAIL_IF(print_timestamp(
+                item->i64,
+                G_transaction_summary_text,
+                TEXT_BUFFER_LENGTH
+            ));
+            break;
     }
     print_string(item->title, G_transaction_summary_title, TITLE_SIZE);
     return 0;

libsol/transaction_summary_test.c

@@ -52,6 +52,11 @@ void test_summary_item_setters() {
     assert(
         strncmp("test", item.sized_string.string, item.sized_string.length) == 0
     );
+
+    summary_item_set_timestamp(&item, "timestamp", 42);
+    assert(item.kind == SummaryItemTimestamp);
+    assert_string_equal(item.title, "timestamp");
+    assert(item.i64 == 42);
 }
 
 void test_summary_item_as_unused() {
@@ -80,6 +85,9 @@ void test_summary_item_as_unused() {
 
     item.kind = SummaryItemString;
     assert(summary_item_as_unused(&item) == NULL);
+
+    item.kind = SummaryItemTimestamp;
+    assert(summary_item_as_unused(&item) == NULL);
 }
 
 void test_transaction_summary_reset() {
@@ -189,6 +197,10 @@ void test_transaction_summary_update_display_for_item() {
     summary_item_set_string(&item, "string", string);
     assert(transaction_summary_update_display_for_item(&item, DisplayFlagNone) == 0);
     assert_transaction_summary_display("string", "value");
+
+    summary_item_set_timestamp(&item, "timestamp", 42);
+    assert(transaction_summary_update_display_for_item(&item, DisplayFlagNone) == 0);
+    assert_transaction_summary_display("timestamp", "1970-01-01 00:00:42");
 }
 
 #define display_item_test_helper(item, item_index)                      \