tools/perf/util/help-unknown-cmd.c

   1 #include "cache.h"
   2 #include <subcmd/help.h>
   3 #include "../builtin.h"
   4 #include "levenshtein.h"
   5
   6 static int autocorrect;
   7 static struct cmdnames aliases;
   8
   9 static int perf_unknown_cmd_config(const char *var, const char *value, void *cb)
  10 {
  11         if (!strcmp(var, "help.autocorrect"))
  12                 autocorrect = perf_config_int(var,value);
  13         /* Also use aliases for command lookup */
  14         if (!prefixcmp(var, "alias."))
  15                 add_cmdname(&aliases, var + 6, strlen(var + 6));
  16
  17         return perf_default_config(var, value, cb);
  18 }
  19
  20 static int levenshtein_compare(const void *p1, const void *p2)
  21 {
  22         const struct cmdname *const *c1 = p1, *const *c2 = p2;
  23         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
  24         int l1 = (*c1)->len;
  25         int l2 = (*c2)->len;
  26         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
  27 }
  28
  29 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
  30 {
  31         unsigned int i;
  32
  33         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
  34
  35         for (i = 0; i < old->cnt; i++)
  36                 cmds->names[cmds->cnt++] = old->names[i];
  37         zfree(&old->names);
  38         old->cnt = 0;
  39 }
  40
  41 const char *help_unknown_cmd(const char *cmd)
  42 {
  43         unsigned int i, n = 0, best_similarity = 0;
  44         struct cmdnames main_cmds, other_cmds;
  45
  46         memset(&main_cmds, 0, sizeof(main_cmds));
  47         memset(&other_cmds, 0, sizeof(main_cmds));
  48         memset(&aliases, 0, sizeof(aliases));
  49
  50         perf_config(perf_unknown_cmd_config, NULL);
  51
  52         load_command_list("perf-", &main_cmds, &other_cmds);
  53
  54         add_cmd_list(&main_cmds, &aliases);
  55         add_cmd_list(&main_cmds, &other_cmds);
  56         qsort(main_cmds.names, main_cmds.cnt,
  57               sizeof(main_cmds.names), cmdname_compare);
  58         uniq(&main_cmds);
  59
  60         if (main_cmds.cnt) {
  61                 /* This reuses cmdname->len for similarity index */
  62                 for (i = 0; i < main_cmds.cnt; ++i)
  63                         main_cmds.names[i]->len =
  64                                 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
  65
  66                 qsort(main_cmds.names, main_cmds.cnt,
  67                       sizeof(*main_cmds.names), levenshtein_compare);
  68
  69                 best_similarity = main_cmds.names[0]->len;
  70                 n = 1;
  71                 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
  72                         ++n;
  73         }
  74
  75         if (autocorrect && n == 1) {
  76                 const char *assumed = main_cmds.names[0]->name;
  77
  78                 main_cmds.names[0] = NULL;
  79                 clean_cmdnames(&main_cmds);
  80                 fprintf(stderr, "WARNING: You called a perf program named '%s', "
  81                         "which does not exist.\n"
  82                         "Continuing under the assumption that you meant '%s'\n",
  83                         cmd, assumed);
  84                 if (autocorrect > 0) {
  85                         fprintf(stderr, "in %0.1f seconds automatically...\n",
  86                                 (float)autocorrect/10.0);
  87                         poll(NULL, 0, autocorrect * 100);
  88                 }
  89                 return assumed;
  90         }
  91
  92         fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);
  93
  94         if (main_cmds.cnt && best_similarity < 6) {
  95                 fprintf(stderr, "\nDid you mean %s?\n",
  96                         n < 2 ? "this": "one of these");
  97
  98                 for (i = 0; i < n; i++)
  99                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 100         }
 101
 102         exit(1);
 103 }