1 files changed, 80 insertions, 0 deletions
diff --git a/gcc/pex.cc b/gcc/pex.cc
new file mode 100644
index 0000000..44a3ff1
--- /dev/null
+++ b/gcc/pex.cc
@@ -0,0 +1,80 @@
+/* C++ wrapper around libiberty's pex API.
+   Copyright (C) 2025 Free Software Foundation, Inc.
+   Contributed by David Malcolm <dmalcolm@redhat.com>.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#define INCLUDE_STRING
+#define INCLUDE_VECTOR
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "pex.h"
+
+/* Read the contents of FILE into memory, or return nullptr
+   if there are any problems.  */
+
+static std::unique_ptr<std::vector<char>>
+read_all_of_file (FILE *f_in)
+{
+  /* Read content, allocating a buffer for it.  */
+  auto result = std::make_unique<std::vector<char>> ();
+  char buf[4096];
+  size_t iter_sz_in;
+
+  while ( (iter_sz_in = fread (buf, 1, sizeof (buf), f_in)) )
+    {
+      size_t old_total_sz = result->size ();
+      size_t new_total_sz = old_total_sz + iter_sz_in;
+      size_t old_alloc_sz = result->capacity ();
+      if (new_total_sz > old_alloc_sz)
+	{
+	  size_t new_alloc_sz = std::max (old_alloc_sz * 2, new_total_sz);
+	  result->reserve (new_alloc_sz);
+	}
+      gcc_assert (result->capacity () >= new_total_sz);
+      result->resize (new_total_sz);
+      memcpy (result->data () + old_total_sz, buf, iter_sz_in);
+    }
+
+  if (!feof (f_in))
+    return nullptr;
+
+  return result;
+}
+
+// struct file_wrapper
+
+std::unique_ptr<std::vector<char>>
+file_wrapper::read_all ()
+{
+  return read_all_of_file (m_file);
+}
+
+// struct pex
+
+const char *
+pex::run (int flags, const char *executable, const std::vector<std::string> &args,
+	  const char *outname, const char *errname, int *err)
+{
+  std::vector<char *> argv;
+  for (auto &iter : args)
+    argv.push_back (const_cast<char *> (iter.c_str ()));
+  argv.push_back (nullptr);
+  return pex_run (m_obj, flags, executable, argv.data (),
+		  outname, errname, err);
+}