src/libgit2/common.h

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #ifndef INCLUDE_common_h__
   8 #define INCLUDE_common_h__
   9
  10 #include "git2_util.h"
  11 #include "errors.h"
  12
  13 /*
  14 * Include the declarations for deprecated functions; this ensures
  15 * that they're decorated with the proper extern/visibility attributes.
  16 */
  17 #include "git2/deprecated.h"
  18
  19 #include "posix.h"
  20
  21 /**
  22  * Initialize a structure with a version.
  23  */
  24 GIT_INLINE(void) git__init_structure(void *structure, size_t len, unsigned int version)
  25 {
  26         memset(structure, 0, len);
  27         *((int*)structure) = version;
  28 }
  29 #define GIT_INIT_STRUCTURE(S,V) git__init_structure(S, sizeof(*S), V)
  30
  31 #define GIT_INIT_STRUCTURE_FROM_TEMPLATE(PTR,VERSION,TYPE,TPL) do { \
  32         TYPE _tmpl = TPL; \
  33         GIT_ERROR_CHECK_VERSION(&(VERSION), _tmpl.version, #TYPE);      \
  34         memcpy((PTR), &_tmpl, sizeof(_tmpl)); } while (0)
  35
  36 /**
  37  * Check a versioned structure for validity
  38  */
  39 GIT_INLINE(int) git_error__check_version(const void *structure, unsigned int expected_max, const char *name)
  40 {
  41         unsigned int actual;
  42
  43         if (!structure)
  44                 return 0;
  45
  46         actual = *(const unsigned int*)structure;
  47         if (actual > 0 && actual <= expected_max)
  48                 return 0;
  49
  50         git_error_set(GIT_ERROR_INVALID, "invalid version %d on %s", actual, name);
  51         return -1;
  52 }
  53 #define GIT_ERROR_CHECK_VERSION(S,V,N) if (git_error__check_version(S,V,N) < 0) return -1
  54
  55 #endif