(SDK) Add memory_stream

libretro-sdk/file/memory_stream.c

@@ -0,0 +1,135 @@
+/* Copyright  (C) 2010-2014 The RetroArch team
+ *
+ * ---------------------------------------------------------------------------------------
+ * The following license statement only applies to this file (memory_stream.c).
+ * ---------------------------------------------------------------------------------------
+ *
+ * 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, sublicense, 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 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 NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 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 <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include "memory_stream.h"
+
+static uint8_t* g_buffer = NULL;
+static size_t g_size = 0;
+
+static size_t last_file_size = 0;
+
+struct memstream
+{
+   uint8_t *m_buf;
+   size_t m_size;
+   size_t m_ptr;
+};
+
+void memstream_set_buffer(uint8_t *buffer, size_t size)
+{
+   g_buffer = buffer;
+   g_size = size;
+}
+
+size_t memstream_get_last_size(void)
+{
+   return last_file_size;
+}
+
+static void memstream_init(memstream_t *stream, uint8_t *buffer, size_t max_size)
+{
+   stream->m_buf = buffer;
+   stream->m_size = max_size;
+   stream->m_ptr = 0;
+}
+
+memstream_t *memstream_open(void)
+{
+	memstream_t *stream;
+   if (!g_buffer || !g_size)
+      return NULL;
+
+   stream = (memstream_t*)calloc(1, sizeof(*stream));
+   memstream_init(stream, g_buffer, g_size);
+
+   g_buffer = NULL;
+   g_size = 0;
+   return stream;
+}
+
+void memstream_close(memstream_t *stream)
+{
+   last_file_size = stream->m_ptr;
+   free(stream);
+}
+
+size_t memstream_read(memstream_t *stream, void *data, size_t bytes)
+{
+   size_t avail = stream->m_size - stream->m_ptr;
+   if (bytes > avail)
+      bytes = avail;
+
+   memcpy(data, stream->m_buf + stream->m_ptr, bytes);
+   stream->m_ptr += bytes;
+   return bytes;
+}
+
+size_t memstream_write(memstream_t *stream, const void *data, size_t bytes)
+{
+   size_t avail = stream->m_size - stream->m_ptr;
+   if (bytes > avail)
+      bytes = avail;
+
+   memcpy(stream->m_buf + stream->m_ptr, data, bytes);
+   stream->m_ptr += bytes;
+   return bytes;
+}
+
+int memstream_seek(memstream_t *stream, int offset, int whence)
+{
+   size_t ptr;
+   if (whence == SEEK_SET)
+      ptr = offset;
+   else if (whence == SEEK_CUR)
+      ptr = stream->m_ptr + offset;
+   else if (whence == SEEK_END)
+      ptr = stream->m_size + offset;
+   else
+      return -1;
+
+   if (ptr <= stream->m_size)
+   {
+      stream->m_ptr = ptr;
+      return 0;
+   }
+   return -1;
+}
+
+size_t memstream_pos(memstream_t *stream)
+{
+   return stream->m_ptr;
+}
+
+char *memstream_gets(memstream_t *stream, char *buffer, size_t len)
+{
+   return NULL;
+}
+
+int memstream_getc(memstream_t *stream)
+{
+   if (stream->m_ptr >= stream->m_size)
+      return EOF;
+   return stream->m_buf[stream->m_ptr++];
+}

libretro-sdk/include/file/memory_stream.h

@@ -0,0 +1,51 @@
+/* Copyright  (C) 2010-2014 The RetroArch team
+ *
+ * ---------------------------------------------------------------------------------------
+ * The following license statement only applies to this file (memory_stream.h).
+ * ---------------------------------------------------------------------------------------
+ *
+ * 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, sublicense, 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 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 NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#ifndef _LIBRETRO_SDK_FILE_MEMORY_STREAM_H
+#define _LIBRETRO_SDK_FILE_MEMORY_STREAM_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct memstream memstream_t;
+
+memstream_t *memstream_open(void);
+
+void memstream_close(memstream_t * stream);
+
+size_t memstream_read(memstream_t * stream, void *data, size_t bytes);
+
+size_t memstream_write(memstream_t * stream, const void *data, size_t bytes);
+
+int memstream_getc(memstream_t * stream);
+
+char *memstream_gets(memstream_t * stream, char *buffer, size_t len);
+
+size_t memstream_pos(memstream_t * stream);
+
+int memstream_seek(memstream_t * stream, int offset, int whence);
+
+void memstream_set_buffer(uint8_t *buffer, size_t size);
+
+size_t memstream_get_last_size(void);
+
+#endif