builtin/bisect--helper.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "parse-options.h"
   4 #include "bisect.h"
   5 #include "refs.h"
   6
   7 static GIT_PATH_FUNC(git_path_bisect_terms, "BISECT_TERMS")
   8 static GIT_PATH_FUNC(git_path_bisect_expected_rev, "BISECT_EXPECTED_REV")
   9 static GIT_PATH_FUNC(git_path_bisect_ancestors_ok, "BISECT_ANCESTORS_OK")
  10
  11 static const char * const git_bisect_helper_usage[] = {
  12         N_("git bisect--helper --next-all [--no-checkout]"),
  13         N_("git bisect--helper --write-terms <bad_term> <good_term>"),
  14         N_("git bisect--helper --bisect-clean-state"),
  15         NULL
  16 };
  17
  18 /*
  19  * Check whether the string `term` belongs to the set of strings
  20  * included in the variable arguments.
  21  */
  22 LAST_ARG_MUST_BE_NULL
  23 static int one_of(const char *term, ...)
  24 {
  25         int res = 0;
  26         va_list matches;
  27         const char *match;
  28
  29         va_start(matches, term);
  30         while (!res && (match = va_arg(matches, const char *)))
  31                 res = !strcmp(term, match);
  32         va_end(matches);
  33
  34         return res;
  35 }
  36
  37 static int check_term_format(const char *term, const char *orig_term)
  38 {
  39         int res;
  40         char *new_term = xstrfmt("refs/bisect/%s", term);
  41
  42         res = check_refname_format(new_term, 0);
  43         free(new_term);
  44
  45         if (res)
  46                 return error(_("'%s' is not a valid term"), term);
  47
  48         if (one_of(term, "help", "start", "skip", "next", "reset",
  49                         "visualize", "view", "replay", "log", "run", "terms", NULL))
  50                 return error(_("can't use the builtin command '%s' as a term"), term);
  51
  52         /*
  53          * In theory, nothing prevents swapping completely good and bad,
  54          * but this situation could be confusing and hasn't been tested
  55          * enough. Forbid it for now.
  56          */
  57
  58         if ((strcmp(orig_term, "bad") && one_of(term, "bad", "new", NULL)) ||
  59                  (strcmp(orig_term, "good") && one_of(term, "good", "old", NULL)))
  60                 return error(_("can't change the meaning of the term '%s'"), term);
  61
  62         return 0;
  63 }
  64
  65 static int write_terms(const char *bad, const char *good)
  66 {
  67         FILE *fp = NULL;
  68         int res;
  69
  70         if (!strcmp(bad, good))
  71                 return error(_("please use two different terms"));
  72
  73         if (check_term_format(bad, "bad") || check_term_format(good, "good"))
  74                 return -1;
  75
  76         fp = fopen(git_path_bisect_terms(), "w");
  77         if (!fp)
  78                 return error_errno(_("could not open the file BISECT_TERMS"));
  79
  80         res = fprintf(fp, "%s\n%s\n", bad, good);
  81         res |= fclose(fp);
  82         return (res < 0) ? -1 : 0;
  83 }
  84
  85 static int is_expected_rev(const char *expected_hex)
  86 {
  87         struct strbuf actual_hex = STRBUF_INIT;
  88         int res = 0;
  89         if (strbuf_read_file(&actual_hex, git_path_bisect_expected_rev(), 0) >= 40) {
  90                 strbuf_trim(&actual_hex);
  91                 res = !strcmp(actual_hex.buf, expected_hex);
  92         }
  93         strbuf_release(&actual_hex);
  94         return res;
  95 }
  96
  97 static void check_expected_revs(const char **revs, int rev_nr)
  98 {
  99         int i;
 100
 101         for (i = 0; i < rev_nr; i++) {
 102                 if (!is_expected_rev(revs[i])) {
 103                         unlink_or_warn(git_path_bisect_ancestors_ok());
 104                         unlink_or_warn(git_path_bisect_expected_rev());
 105                 }
 106         }
 107 }
 108
 109 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 110 {
 111         enum {
 112                 NEXT_ALL = 1,
 113                 WRITE_TERMS,
 114                 BISECT_CLEAN_STATE,
 115                 CHECK_EXPECTED_REVS
 116         } cmdmode = 0;
 117         int no_checkout = 0;
 118         struct option options[] = {
 119                 OPT_CMDMODE(0, "next-all", &cmdmode,
 120                          N_("perform 'git bisect next'"), NEXT_ALL),
 121                 OPT_CMDMODE(0, "write-terms", &cmdmode,
 122                          N_("write the terms to .git/BISECT_TERMS"), WRITE_TERMS),
 123                 OPT_CMDMODE(0, "bisect-clean-state", &cmdmode,
 124                          N_("cleanup the bisection state"), BISECT_CLEAN_STATE),
 125                 OPT_CMDMODE(0, "check-expected-revs", &cmdmode,
 126                          N_("check for expected revs"), CHECK_EXPECTED_REVS),
 127                 OPT_BOOL(0, "no-checkout", &no_checkout,
 128                          N_("update BISECT_HEAD instead of checking out the current commit")),
 129                 OPT_END()
 130         };
 131
 132         argc = parse_options(argc, argv, prefix, options,
 133                              git_bisect_helper_usage, 0);
 134
 135         if (!cmdmode)
 136                 usage_with_options(git_bisect_helper_usage, options);
 137
 138         switch (cmdmode) {
 139         case NEXT_ALL:
 140                 return bisect_next_all(prefix, no_checkout);
 141         case WRITE_TERMS:
 142                 if (argc != 2)
 143                         return error(_("--write-terms requires two arguments"));
 144                 return write_terms(argv[0], argv[1]);
 145         case BISECT_CLEAN_STATE:
 146                 if (argc != 0)
 147                         return error(_("--bisect-clean-state requires no arguments"));
 148                 return bisect_clean_state();
 149         case CHECK_EXPECTED_REVS:
 150                 check_expected_revs(argv, argc);
 151                 return 0;
 152         default:
 153                 return error("BUG: unknown subcommand '%d'", cmdmode);
 154         }
 155         return 0;
 156 }