Travel3: Simple image and video display site

Reads the images and videos from filesystem and builds a site in
memroy.

1 files changed, 66 insertions, 0 deletions

diff --git a/src/date.cc b/src/date.cc
new file mode 100644
index 0000000..23f0ad6
--- /dev/null
+++ b/src/date.cc
@@ -0,0 +1,66 @@
+#include "common.hh"
+
+#include "date.hh"
+
+#include <pthread.h>
+#include <time.h>
+
+namespace {
+
+// localtime_r doesn't guarantee to call tzset as localtime does.
+pthread_once_t tzset_called = PTHREAD_ONCE_INIT;
+
+}  // namespace
+
+Date Date::from_format(std::string const& format,
+                       std::string const& str,
+                       bool local_time) {
+  struct tm tm = {};
+  tm.tm_isdst = -1;  // Must be -1 so that mktime figures it out by itself.
+  auto* end = strptime(str.c_str(), format.c_str(), &tm);
+  if (end && !*end)
+    return local_time ? mktime(&tm) : timegm(&tm);
+  return Date();
+}
+
+std::string Date::to_format(std::string const& format,
+                            bool local_time) const {
+  if (empty() || format.empty())
+    return std::string();
+
+  if (local_time)
+    pthread_once(&tzset_called, tzset);
+
+  struct tm mem = {};
+  auto* tm = local_time ? localtime_r(&time_, &mem) : gmtime_r(&time_, &mem);
+  if (!tm)
+    return std::string();
+
+  std::string ret;
+  ret.resize(64);
+  while (true) {
+    auto len = strftime(ret.data(), ret.size(), format.c_str(), tm);
+    if (len > 0) {
+      ret.resize(len);
+      return ret;
+    }
+    ret.resize(ret.size() * 2);
+  }
+}
+
+Date Date::day(bool local_time) const {
+  if (empty())
+    return *this;
+
+  if (local_time)
+    pthread_once(&tzset_called, tzset);
+
+  struct tm tm = {};
+  auto* ret = local_time ? localtime_r(&time_, &tm) : gmtime_r(&time_, &tm);
+  if (!ret)
+    return *this;
+  ret->tm_hour = 0;
+  ret->tm_min = 0;
+  ret->tm_sec = 0;
+  return local_time ? mktime(ret) : timegm(ret);
+}