Turn unique_ptr<decltype(fclose and free)> into real deleter types (warnings now, UB in C++20)

5 files changed, 25 insertions, 13 deletions

diff --git a/apt-pkg/acquire-item.cc b/apt-pkg/acquire-item.cc
index b534d56a3..3016dad59 100644
--- a/apt-pkg/acquire-item.cc
+++ b/apt-pkg/acquire-item.cc
@@ -4065,7 +4065,7 @@ static std::string GetAuxFileNameFromURIInLists(std::string const &uri)
    auto const dirname = flCombine(_config->FindDir("Dir::State::lists"), "auxfiles/");
    char const * const filetag = ".apt-acquire-privs-test.XXXXXX";
    std::string const tmpfile_tpl = flCombine(dirname, filetag);
-   std::unique_ptr<char, decltype(std::free) *> tmpfile { strdup(tmpfile_tpl.c_str()), std::free };
+   std::unique_ptr<char, FreeDeleter> tmpfile { strdup(tmpfile_tpl.c_str()) };
    int const fd = mkstemp(tmpfile.get());
    if (fd == -1)
       return "";
@@ -4081,7 +4081,7 @@ static std::string GetAuxFileNameFromURI(std::string const &uri)
 
    std::string tmpdir_tpl;
    strprintf(tmpdir_tpl, "%s/apt-auxfiles-XXXXXX", GetTempDir().c_str());
-   std::unique_ptr<char, decltype(std::free) *> tmpdir { strndup(tmpdir_tpl.data(), tmpdir_tpl.length()), std::free };
+   std::unique_ptr<char, FreeDeleter> tmpdir { strndup(tmpdir_tpl.data(), tmpdir_tpl.length()) };
    if (mkdtemp(tmpdir.get()) == nullptr)
    {
       _error->Errno("GetAuxFileNameFromURI", "mkdtemp of %s failed", tmpdir.get());
diff --git a/apt-pkg/acquire.cc b/apt-pkg/acquire.cc
index 7ebfa4ffe..f367e4310 100644
--- a/apt-pkg/acquire.cc
+++ b/apt-pkg/acquire.cc
@@ -605,7 +605,7 @@ static bool IsAccessibleBySandboxUser(std::string const &filename, bool const Re
 
       char const * const filetag = ".apt-acquire-privs-test.XXXXXX";
       std::string const tmpfile_tpl = flCombine(dirname, filetag);
-      std::unique_ptr<char, decltype(std::free) *> tmpfile { strdup(tmpfile_tpl.c_str()), std::free };
+      std::unique_ptr<char, FreeDeleter> tmpfile { strdup(tmpfile_tpl.c_str()) };
       int const fd = mkstemp(tmpfile.get());
       if (fd == -1 && errno == EACCES)
 	 return false;
diff --git a/apt-pkg/contrib/gpgv.cc b/apt-pkg/contrib/gpgv.cc
index 225acae88..9ab3e066e 100644
--- a/apt-pkg/contrib/gpgv.cc
+++ b/apt-pkg/contrib/gpgv.cc
@@ -28,14 +28,17 @@
 #include <apti18n.h>
 									/*}}}*/
 
-// syntactic sugar to wrap a raw pointer with a custom deleter in a std::unique_ptr
-static std::unique_ptr<char, decltype(&free)> make_unique_char(void *const str = nullptr)
-{
-   return {static_cast<char *>(str), &free};
+namespace {
+   struct FILEDeleter {
+      void operator()(FILE *p) {
+         fclose(p);
+      }
+   };
 }
-static std::unique_ptr<FILE, decltype(&fclose)> make_unique_FILE(std::string const &filename, char const *const mode)
+
+static std::unique_ptr<FILE, FILEDeleter> make_unique_FILE(std::string const &filename, char const *const mode)
 {
-   return {fopen(filename.c_str(), mode), &fclose};
+   return {fopen(filename.c_str(), mode), {}};
 }
 
 class LineBuffer							/*{{{*/
@@ -207,9 +210,9 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG,
    }
 
    enum  { DETACHED, CLEARSIGNED } releaseSignature = (FileGPG != File) ? DETACHED : CLEARSIGNED;
-   auto sig = make_unique_char();
-   auto data = make_unique_char();
-   auto conf = make_unique_char();
+   std::unique_ptr<char, FreeDeleter> sig;
+   std::unique_ptr<char, FreeDeleter> data;
+   std::unique_ptr<char, FreeDeleter> conf;
 
    // Dump the configuration so apt-key picks up the correct Dir values
    {
diff --git a/apt-pkg/contrib/strutl.cc b/apt-pkg/contrib/strutl.cc
index 3689dc17a..ec61c7e2b 100644
--- a/apt-pkg/contrib/strutl.cc
+++ b/apt-pkg/contrib/strutl.cc
@@ -1421,7 +1421,7 @@ unsigned long RegexChoice(RxChoiceList *Rxs,const char **ListBegin,
    and to allow reordering of parameters */
 bool iovprintf(std::ostream &out, const char *format,
 		      va_list &args, ssize_t &size) {
-   auto S = std::unique_ptr<char,decltype(&free)>{static_cast<char*>(malloc(size)), &free};
+   auto S = std::unique_ptr<char,FreeDeleter>{static_cast<char*>(malloc(size))};
    ssize_t const n = vsnprintf(S.get(), size, format, args);
    if (n > -1 && n < size) {
       out << S.get();
diff --git a/apt-pkg/contrib/strutl.h b/apt-pkg/contrib/strutl.h
index 7cf9b456d..152477eee 100644
--- a/apt-pkg/contrib/strutl.h
+++ b/apt-pkg/contrib/strutl.h
@@ -31,6 +31,15 @@
 #include "macros.h"
 
 
+namespace {
+   struct FreeDeleter {
+      void operator()(void *p) {
+         free(p);
+      }
+   };
+}
+
+
 namespace APT {
    namespace String {
       APT_PUBLIC std::string Strip(const std::string &s);