use more stringFormat

Signed-off-by: Rosen Penev <[email protected]>

src/convert.cpp

@@ -13,6 +13,7 @@
 #include "error.hpp"
 #include "exif.hpp"
 #include "futils.hpp"
+#include "image_int.hpp"
 #include "iptc.hpp"
 #include "types.hpp"
 #include "xmp_exiv2.hpp"
@@ -621,7 +622,6 @@ void Converter::cnvExifDate(const char* from, const char* to) {
   int min = 0;
   int sec = 0;
   std::string subsec;
-  char buf[30];
 
   if (std::string(from) != "Exif.GPSInfo.GPSTimeStamp") {
     std::string value = pos->toString();
@@ -678,10 +678,7 @@ void Converter::cnvExifDate(const char* from, const char* to) {
     sec = static_cast<int>(dsec);
     dsec -= sec;
 
-    snprintf(buf, sizeof(buf), "%.9f", dsec);
-    buf[sizeof(buf) - 1] = 0;
-    buf[1] = '.';  // some locales use ','
-    subsec = buf + 1;
+    subsec = std::format(".{:09.0f}", dsec * 1'000'000'000);
 
     auto datePos = exifData_->findKey(ExifKey("Exif.GPSInfo.GPSDateStamp"));
     if (datePos == exifData_->end()) {
@@ -733,10 +730,8 @@ void Converter::cnvExifDate(const char* from, const char* to) {
 
   if (subsec.size() > 10)
     subsec.resize(10);
-  snprintf(buf, sizeof(buf), "%4d-%02d-%02dT%02d:%02d:%02d%s", year, month, day, hour, min, sec, subsec.c_str());
-  buf[sizeof(buf) - 1] = 0;
 
-  (*xmpData_)[to] = buf;
+  (*xmpData_)[to] = stringFormat("{:4}-{:02}-{:02}T{:02}:{:02}:{:02}{}", year, month, day, hour, min, sec, subsec);
   if (erase_)
     exifData_->erase(pos);
 }
@@ -923,14 +918,11 @@ void Converter::cnvXmpDate(const char* from, const char* to) {
   XMP_DateTime datetime;
   try {
     SXMPUtils::ConvertToDate(value, &datetime);
-    char buf[30];
     if (std::string(to) != "Exif.GPSInfo.GPSTimeStamp") {
       SXMPUtils::ConvertToLocalTime(&datetime);
 
-      snprintf(buf, sizeof(buf), "%4d:%02d:%02d %02d:%02d:%02d", datetime.year, datetime.month, datetime.day,
-               datetime.hour, datetime.minute, datetime.second);
-      buf[sizeof(buf) - 1] = 0;
-      (*exifData_)[to] = buf;
+      (*exifData_)[to] = stringFormat("{:4}:{:02}:{:02} {:02}:{:02}:{:02}", datetime.year, datetime.month, datetime.day,
+                                      datetime.hour, datetime.minute, datetime.second);
 
       if (datetime.nanoSecond) {
         const char* subsecTag = nullptr;
@@ -968,9 +960,8 @@ void Converter::cnvXmpDate(const char* from, const char* to) {
       (*exifData_)[to] = array.str();
 
       prepareExifTarget("Exif.GPSInfo.GPSDateStamp", true);
-      snprintf(buf, sizeof(buf), "%4d:%02d:%02d", datetime.year, datetime.month, datetime.day);
-      buf[sizeof(buf) - 1] = 0;
-      (*exifData_)["Exif.GPSInfo.GPSDateStamp"] = buf;
+      (*exifData_)["Exif.GPSInfo.GPSDateStamp"] =
+          stringFormat("{:4}:{:02}:{:02}", datetime.year, datetime.month, datetime.day);
     }
   }
 #ifndef SUPPRESS_WARNINGS

src/image_int.hpp

@@ -16,10 +16,12 @@
 #include <format>
 #endif
 #ifndef EXV_HAVE_STD_FORMAT
-#include <fmt/core.h>
+#include <fmt/format.h>
 #define stringFormat fmt::format
+#define stringFormatTo fmt::format_to
 #else
 #define stringFormat std::format
+#define stringFormatTo std::format_to
 #endif
 
 // *****************************************************************************

src/iptc.cpp

@@ -291,10 +291,10 @@ void IptcData::printStructure(std::ostream& out, const Slice<byte*>& bytes, size
     uint16_t dataset = bytes.at(i + 2);
     Internal::enforce(bytes.size() - i >= 5, ErrorCode::kerCorruptedMetadata);
     uint16_t len = getUShort(bytes.subSlice(i + 3, bytes.size()), bigEndian);
-    snprintf(buff, sizeof(buff), "  %6hu | %7hu | %-24s | %6hu | ", record, dataset,
-             Exiv2::IptcDataSets::dataSetName(dataset, record).c_str(), len);
 
     Internal::enforce(bytes.size() - i >= 5 + static_cast<size_t>(len), ErrorCode::kerCorruptedMetadata);
+    out << std::format("  {:6} | {:7} | {:<24} | {:6} | ", record, dataset,
+                       Exiv2::IptcDataSets::dataSetName(dataset, record), len);
     out << buff << Internal::binaryToString(makeSlice(bytes, i + 5, i + 5 + (len > 40 ? 40 : len)))
         << (len > 40 ? "..." : "") << '\n';
     i += 5 + len;

src/jpgimage.cpp

@@ -357,12 +357,9 @@ void JpegBase::printStructure(std::ostream& out, PrintStructureOption option, si
     // 0xc0 .. 0xcf are SOFn (except 4)
     nm[0xc4] = "DHT";
     for (int i = 0; i <= 15; i++) {
-      char MN[16];
-      snprintf(MN, sizeof(MN), "APP%d", i);
-      nm[0xe0 + i] = MN;
+      nm[0xe0 + i] = stringFormat("APP{}", i);
       if (i != 4) {
-        snprintf(MN, sizeof(MN), "SOF%d", i);
-        nm[0xc0 + i] = MN;
+        nm[0xc0 + i] = stringFormat("SOF{}", i);
       }
     }
 

src/meson.build

@@ -92,7 +92,7 @@ convertlib = static_library(
   'convert.cpp',
   cpp_args: cargs,
   gnu_symbol_visibility: 'hidden',
-  dependencies: iconv_dep,
+  dependencies: [fmt_dep, iconv_dep],
   include_directories: libinc,
   build_by_default: false,
 )

src/value.cpp

@@ -817,11 +817,10 @@ size_t DateValue::copy(byte* buf, ByteOrder /*byteOrder*/) const {
   // \note Here the date is copied in the Basic format YYYYMMDD, as the IPTC key	Iptc.Application2.DateCreated
   // wants it. Check https://exiv2.org/iptc.html
 
-  // sprintf wants to add the null terminator, so use oversized buffer
-  char temp[9];
-  auto wrote = static_cast<size_t>(snprintf(temp, sizeof(temp), "%04d%02d%02d", date_.year, date_.month, date_.day));
-  std::copy_n(temp, wrote, buf);
-  return wrote;
+  auto out = reinterpret_cast<char*>(buf);
+  auto it = std::format_to(out, "{:04}{:02}{:02}", date_.year, date_.month, date_.day);
+
+  return it - out;
 }
 
 const DateValue::Date& DateValue::getDate() const {
@@ -987,17 +986,17 @@ void TimeValue::setTime(const Time& src) {
 size_t TimeValue::copy(byte* buf, ByteOrder /*byteOrder*/) const {
   // NOTE: Here the time is copied in the Basic format HHMMSS:HHMM, as the IPTC key
   // Iptc.Application2.TimeCreated wants it. Check https://exiv2.org/iptc.html
-  char temp[12];
   char plusMinus = '+';
   if (time_.tzHour < 0 || time_.tzMinute < 0)
     plusMinus = '-';
 
-  const auto wrote = static_cast<size_t>(snprintf(temp, sizeof(temp),  // 11 bytes are written + \0
-                                                  "%02d%02d%02d%1c%02d%02d", time_.hour, time_.minute, time_.second,
-                                                  plusMinus, abs(time_.tzHour), abs(time_.tzMinute)));
+  auto out = reinterpret_cast<char*>(buf);
+  auto it = std::format_to(out, "{:02}{:02}{:02}{}{:02}{:02}",
+                             time_.hour, time_.minute, time_.second,
+                             plusMinus, std::abs(time_.tzHour), std::abs(time_.tzMinute));
 
+  auto wrote = static_cast<size_t>(it - out);
   Internal::enforce(wrote == 11, Exiv2::ErrorCode::kerUnsupportedTimeFormat);
-  std::copy_n(temp, wrote, buf);
   return wrote;
 }