vcs.maemo.org Git - busybox-power/blob - debian/patches/ash-history-buffer.patch

   1 Allows the user to specify a location at compile time for temporarily storing ash's history file until the shell is closed.
   2 NB This is only useful if ASH_HIST_BUFFER_PATH points to an in-memory filesystem.
   3 By Dennis Groenen <tj.groenen@gmail.com> - 2011-07-31
   4 ---
   5
   6 --- a/shell/ash.c
   7 +++ b/shell/ash.c
   8 @@ -182,6 +182,24 @@
   9  //config:        This option recreates the prompt string from the environment
  10  //config:        variable each time it is displayed.
  11  //config:
  12 +//config:config ASH_HIST_BUFFER
  13 +//config:      bool "History buffer"
  14 +//config:      default n
  15 +//config:      depends on ASH && FEATURE_EDITING_SAVEHISTORY
  16 +//config:      help
  17 +//config:        Allows you to set a temporary location for .ash_history.
  18 +//config:        History is saved to this custom location, and written out to
  19 +//config:        its default location (~/.ash_history) upon shell exit.
  20 +//config:        Useful to prevent wear on flash-based storage devices.
  21 +//config:
  22 +//config:config ASH_HIST_BUFFER_PATH
  23 +//config:      string "History buffer location"
  24 +//config:      default "/tmp"
  25 +//config:      depends on ASH && ASH_HIST_BUFFER
  26 +//config:      help
  27 +//config:        Directory which will be used to save the shell history until
  28 +//config:        ash is exited.
  29 +//config:
  30
  31  //usage:#define ash_trivial_usage NOUSAGE_STR
  32  //usage:#define ash_full_usage ""
  33 @@ -12810,6 +12828,14 @@ exitshell(void)
  34         char *p;
  35         int status;
  36
  37 +#if ENABLE_ASH_HIST_BUFFER
  38 +       const char *tmphistory = lookupvar("HISTFILE");
  39 +       const char *storedhistory = lookupvar("STOREDHISTFILE");
  40 +
  41 +       if (storedhistory) /* is NULL when setting up the history buffer failed; check for this before copying */
  42 +               copy_file(tmphistory, storedhistory, FILEUTILS_FORCE | FILEUTILS_DEREFERENCE | FILEUTILS_PRESERVE_STATUS);
  43 +#endif
  44 +
  45         status = exitstatus;
  46         TRACE(("pid %d, exitshell(%d)\n", getpid(), status));
  47         if (setjmp(loc.loc)) {
  48 @@ -13056,9 +13082,59 @@ int ash_main(int argc UNUSED_PARAM, char
  49                 if (hp == NULL) {
  50                         hp = lookupvar("HOME");
  51                         if (hp != NULL) {
  52 +#if ENABLE_ASH_HIST_BUFFER
  53 +                               char *tmppath;
  54 +                               char *tmphistory;
  55 +                               char *storedhistory;
  56 +                               const char *user = lookupvar("USER");
  57 +
  58 +                               tmppath = concat_path_file(CONFIG_ASH_HIST_BUFFER_PATH, user);
  59 +                               tmphistory = concat_path_file(tmppath, ".ash_history");
  60 +                               storedhistory = concat_path_file(hp, ".ash_history");
  61 +
  62 +                               if (access(CONFIG_ASH_HIST_BUFFER_PATH, R_OK == -1)) {
  63 +                                       bb_simple_perror_msg("could not access history buffer path");
  64 +                                       goto bail;
  65 +                               }
  66 +
  67 +                               if (bb_make_directory(tmppath, S_IRWXU, FILEUTILS_RECUR)) {
  68 +                                       /* bb_make_directory is noisy, no need for an additional error message */
  69 +                                       goto bail;
  70 +                               } else {
  71 +                                       struct stat stat_tmppath;
  72 +                                       stat(tmppath, &stat_tmppath);
  73 +                                       if (stat_tmppath.st_uid != geteuid() || stat_tmppath.st_mode & (S_IRWXG | S_IRWXO)) {
  74 +                                               errno = 0;
  75 +                                               bb_simple_perror_msg("history buffer is not exclusive to the shell user");
  76 +                                               goto bail;
  77 +                                       }
  78 +                               }
  79 +
  80 +                               if (access(tmphistory, R_OK | W_OK) == -1) {
  81 +                                       if (access(storedhistory, R_OK) != -1) {
  82 +                                               if (copy_file(storedhistory, tmphistory, FILEUTILS_FORCE | FILEUTILS_DEREFERENCE | FILEUTILS_PRESERVE_STATUS) == -1) {
  83 +                                                       /* copy_file is noisy too, no need for an additional error message */
  84 +                                                       goto bail;
  85 +                                               }
  86 +                                       }
  87 +                               }
  88 +                               setvar("STOREDHISTFILE", storedhistory, 0);
  89 +                               goto out;
  90 +
  91 + bail:
  92 +                               errno = 0;
  93 +                               bb_simple_perror_msg("shell history will not be saved");
  94 +                               tmphistory = xasprintf("/dev/null");
  95 + out:
  96 +                               setvar("HISTFILE", tmphistory, 0);
  97 +                               free(storedhistory);
  98 +                               free(tmphistory);
  99 +                               free(tmppath);
 100 +#else
 101                                 char *defhp = concat_path_file(hp, ".ash_history");
 102                                 setvar("HISTFILE", defhp, 0);
 103                                 free(defhp);
 104 +#endif
 105                         }
 106                 }
 107         }