tmp-objdir.h

   1 #ifndef TMP_OBJDIR_H
   2 #define TMP_OBJDIR_H
   3
   4 /*
   5  * This API allows you to create a temporary object directory, advertise it to
   6  * sub-processes via GIT_OBJECT_DIRECTORY and GIT_ALTERNATE_OBJECT_DIRECTORIES,
   7  * and then either migrate its object into the main object directory, or remove
   8  * it. The library handles unexpected signal/exit death by cleaning up the
   9  * temporary directory.
  10  *
  11  * Example:
  12  *
  13  *      struct child_process child = CHILD_PROCESS_INIT;
  14  *      struct tmp_objdir *t = tmp_objdir_create("incoming");
  15  *      strvec_push(&child.args, cmd);
  16  *      strvec_pushv(&child.env, tmp_objdir_env(t));
  17  *      if (!run_command(&child)) && !tmp_objdir_migrate(t))
  18  *              printf("success!\n");
  19  *      else
  20  *              die("failed...tmp_objdir will clean up for us");
  21  *
  22  */
  23
  24 struct tmp_objdir;
  25
  26 /*
  27  * Create a new temporary object directory with the specified prefix;
  28  * returns NULL on failure.
  29  */
  30 struct tmp_objdir *tmp_objdir_create(const char *prefix);
  31
  32 /*
  33  * Return a list of environment strings, suitable for use with
  34  * child_process.env, that can be passed to child programs to make use of the
  35  * temporary object directory.
  36  */
  37 const char **tmp_objdir_env(const struct tmp_objdir *);
  38
  39 /*
  40  * Finalize a temporary object directory by migrating its objects into the main
  41  * object database, removing the temporary directory, and freeing any
  42  * associated resources.
  43  */
  44 int tmp_objdir_migrate(struct tmp_objdir *);
  45
  46 /*
  47  * Destroy a temporary object directory, discarding any objects it contains.
  48  */
  49 int tmp_objdir_destroy(struct tmp_objdir *);
  50
  51 /*
  52  * Remove all objects from the temporary object directory, while leaving it
  53  * around so more objects can be added.
  54  */
  55 void tmp_objdir_discard_objects(struct tmp_objdir *);
  56
  57 /*
  58  * Add the temporary object directory as an alternate object store in the
  59  * current process.
  60  */
  61 void tmp_objdir_add_as_alternate(const struct tmp_objdir *);
  62
  63 /*
  64  * Replaces the writable object store in the current process with the temporary
  65  * object directory and makes the former main object store an alternate.
  66  * If will_destroy is nonzero, the object directory may not be migrated.
  67  */
  68 void tmp_objdir_replace_primary_odb(struct tmp_objdir *, int will_destroy);
  69
  70 /*
  71  * If the primary object database was replaced by a temporary object directory,
  72  * restore it to its original value while keeping the directory contents around.
  73  * Returns NULL if the primary object database was not replaced.
  74  */
  75 struct tmp_objdir *tmp_objdir_unapply_primary_odb(void);
  76
  77 /*
  78  * Reapplies the former primary temporary object database, after potentially
  79  * changing its relative path.
  80  */
  81 void tmp_objdir_reapply_primary_odb(struct tmp_objdir *, const char *old_cwd,
  82                 const char *new_cwd);
  83
  84
  85 #endif /* TMP_OBJDIR_H */