Add an API to unpack Zip files directly from and to file descriptors.

third_party/zlib/contrib/minizip/ioapi.c

 /* ioapi.c -- IO base function header for compress/uncompress .zip
    files using zlib + zip or unzip API
 
    Version 1.01e, February 12th, 2005
 
    Copyright (C) 1998-2005 Gilles Vollant
 */
 
 #include <stdio.h>
 #include <stdlib.h>
@@ skipping 71 matching lines @@
         mode_fopen = "r+b";
     else
     if (mode & ZLIB_FILEFUNC_MODE_CREATE)
         mode_fopen = "wb";
 
     if ((filename!=NULL) && (mode_fopen != NULL))
         file = fopen(filename, mode_fopen);
     return file;
 }
 
+// Google
+voidpf ZCALLBACK fdopen_file_func (opaque, filename, mode)
+   voidpf opaque;
+   const char* filename;
+   int mode;
+{
+    FILE* file = NULL;
+    const char* mode_fopen = NULL;
+    if ((mode & ZLIB_FILEFUNC_MODE_READWRITEFILTER)==ZLIB_FILEFUNC_MODE_READ)
+        mode_fopen = "rb";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_EXISTING)
+        mode_fopen = "r+b";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_CREATE)
+        mode_fopen = "wb";
+
+    if ((filename!=NULL) && (mode_fopen != NULL))
+        file = fdopen(*(int*)opaque, mode_fopen);
+    return file;
+}
+
 
 uLong ZCALLBACK fread_file_func (opaque, stream, buf, size)
    voidpf opaque;
    voidpf stream;
    void* buf;
    uLong size;
 {
     uLong ret;
     ret = (uLong)fread(buf, 1, (size_t)size, (FILE *)stream);
     return ret;
@@ skipping 69 matching lines @@
 {
     pzlib_filefunc_def->zopen_file = fopen_file_func;
     pzlib_filefunc_def->zread_file = fread_file_func;
     pzlib_filefunc_def->zwrite_file = fwrite_file_func;
     pzlib_filefunc_def->ztell_file = ftell_file_func;
     pzlib_filefunc_def->zseek_file = fseek_file_func;
     pzlib_filefunc_def->zclose_file = fclose_file_func;
     pzlib_filefunc_def->zerror_file = ferror_file_func;
     pzlib_filefunc_def->opaque = NULL;
 }
+
+// Google
+void fill_fdopen_filefunc (pzlib_filefunc_def, fd)
+  zlib_filefunc_def* pzlib_filefunc_def;
+  const int fd;
+{
+    fill_fopen_filefunc(pzlib_filefunc_def);
+    pzlib_filefunc_def->zopen_file = fdopen_file_func;
+    int *ptr_fd = malloc(sizeof(int));
+    *ptr_fd = fd;
+    pzlib_filefunc_def->opaque = ptr_fd;
+}