1 // SPDX-License-Identifier: GPL-2.0
7 #include <subcmd/help.h>
8 #include "../builtin.h"
9 #include "levenshtein.h"
10 #include <linux/zalloc.h>
12 static int autocorrect;
14 static int perf_unknown_cmd_config(const char *var, const char *value,
15 void *cb __maybe_unused)
17 if (!strcmp(var, "help.autocorrect"))
18 return perf_config_int(&autocorrect, var,value);
23 static int levenshtein_compare(const void *p1, const void *p2)
25 const struct cmdname *const *c1 = p1, *const *c2 = p2;
26 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
29 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
32 static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
34 unsigned int i, nr = cmds->cnt + old->cnt;
37 if (nr > cmds->alloc) {
38 /* Choose bigger one to alloc */
39 if (alloc_nr(cmds->alloc) < nr)
42 cmds->alloc = alloc_nr(cmds->alloc);
43 tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
48 for (i = 0; i < old->cnt; i++)
49 cmds->names[cmds->cnt++] = old->names[i];
55 const char *help_unknown_cmd(const char *cmd, struct cmdnames *main_cmds)
57 unsigned int i, n = 0, best_similarity = 0;
58 struct cmdnames other_cmds;
60 memset(&other_cmds, 0, sizeof(other_cmds));
62 perf_config(perf_unknown_cmd_config, NULL);
64 load_command_list("perf-", main_cmds, &other_cmds);
66 if (add_cmd_list(main_cmds, &other_cmds) < 0) {
67 fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
70 qsort(main_cmds->names, main_cmds->cnt,
71 sizeof(main_cmds->names), cmdname_compare);
75 /* This reuses cmdname->len for similarity index */
76 for (i = 0; i < main_cmds->cnt; ++i) {
77 main_cmds->names[i]->len =
78 levenshtein(cmd, main_cmds->names[i]->name,
80 /*substition_penality=*/2,
81 /*insertion_penality=*/1,
82 /*deletion_penalty=*/1);
84 qsort(main_cmds->names, main_cmds->cnt,
85 sizeof(*main_cmds->names), levenshtein_compare);
87 best_similarity = main_cmds->names[0]->len;
89 while (n < main_cmds->cnt && best_similarity == main_cmds->names[n]->len)
93 if (autocorrect && n == 1) {
94 const char *assumed = main_cmds->names[0]->name;
96 main_cmds->names[0] = NULL;
97 clean_cmdnames(&other_cmds);
98 fprintf(stderr, "WARNING: You called a perf program named '%s', "
99 "which does not exist.\n"
100 "Continuing under the assumption that you meant '%s'\n",
102 if (autocorrect > 0) {
103 fprintf(stderr, "in %0.1f seconds automatically...\n",
104 (float)autocorrect/10.0);
105 poll(NULL, 0, autocorrect * 100);
110 fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);
112 if (main_cmds->cnt && best_similarity < 6) {
113 fprintf(stderr, "\nDid you mean %s?\n",
114 n < 2 ? "this": "one of these");
116 for (i = 0; i < n; i++)
117 fprintf(stderr, "\t%s\n", main_cmds->names[i]->name);
120 clean_cmdnames(&other_cmds);