init

src/util/memstream.c

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+/*
+ * Copyright 2020 Lag Free Games, LLC
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "memstream.h"
+
+#include <stdlib.h>
+
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+bool
+u_memstream_open(struct u_memstream *mem, char **bufp, size_t *sizep)
+{
+#ifdef _GAMING_XBOX
+   int err = tmpfile_s(&mem->f);
+   mem->bufp = bufp;
+   mem->sizep = sizep;
+
+   return err == 0;
+#elif defined(_WIN32)
+   bool success = false;
+
+   char path[MAX_PATH];
+   DWORD dwResult = GetTempPath(MAX_PATH, path);
+   if ((dwResult > 0) && (dwResult < MAX_PATH)) {
+      char *temp = mem->temp;
+      UINT uResult = GetTempFileName(path, "MEMSTREAM", 0, temp);
+      if (uResult != 0) {
+         FILE *f = fopen(temp, "w+b");
+         success = f != NULL;
+         if (success)
+         {
+            *bufp = NULL;
+            *sizep = 0;
+            mem->f = f;
+            mem->bufp = bufp;
+            mem->sizep = sizep;
+         }
+      }
+   }
+
+   return success;
+#else
+   FILE *const f = open_memstream(bufp, sizep);
+   mem->f = f;
+   return f != NULL;
+#endif
+}
+
+#ifdef _WIN32
+static void
+u_memstream_update_buffer(struct u_memstream *mem)
+{
+   FILE *const f = mem->f;
+   long size = ftell(f);
+   if (size > 0) {
+      /* reserve space for the null terminator as well */
+      if (*mem->bufp == NULL || *mem->sizep < size + 1)
+         *mem->bufp = realloc(*mem->bufp, size + 1);
+
+      fseek(f, 0, SEEK_SET);
+      fread(*mem->bufp, 1, size, f);
+      (*mem->bufp)[size] = '\0';
+   }
+   *mem->sizep = size;
+}
+#endif /* _WIN32 */
+
+void
+u_memstream_close(struct u_memstream *mem)
+{
+   FILE *const f = mem->f;
+
+#ifdef _WIN32
+   u_memstream_update_buffer(mem);
+   remove(mem->temp);
+#endif
+
+   fclose(f);
+}
+
+int
+u_memstream_flush(struct u_memstream *mem)
+{
+#ifndef _WIN32
+   return fflush(mem->f);
+#else
+   u_memstream_update_buffer(mem);
+   return 0;
+#endif /* _WIN32 */
+}