1 // SPDX-License-Identifier: GPL-2.0
2 #include "cache.h"
3 #include "config.h"
4 #include <poll.h>
5 #include <stdio.h>
6 #include <subcmd/help.h>
7 #include "../builtin.h"
8 #include "levenshtein.h"
9
10 static int autocorrect;
11
perf_unknown_cmd_config(const char * var,const char * value,void * cb __maybe_unused)12 static int perf_unknown_cmd_config(const char *var, const char *value,
13 void *cb __maybe_unused)
14 {
15 if (!strcmp(var, "help.autocorrect"))
16 return perf_config_int(&autocorrect, var,value);
17
18 return 0;
19 }
20
levenshtein_compare(const void * p1,const void * p2)21 static int levenshtein_compare(const void *p1, const void *p2)
22 {
23 const struct cmdname *const *c1 = p1, *const *c2 = p2;
24 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
25 int l1 = (*c1)->len;
26 int l2 = (*c2)->len;
27 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
28 }
29
add_cmd_list(struct cmdnames * cmds,struct cmdnames * old)30 static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
31 {
32 unsigned int i, nr = cmds->cnt + old->cnt;
33 void *tmp;
34
35 if (nr > cmds->alloc) {
36 /* Choose bigger one to alloc */
37 if (alloc_nr(cmds->alloc) < nr)
38 cmds->alloc = nr;
39 else
40 cmds->alloc = alloc_nr(cmds->alloc);
41 tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
42 if (!tmp)
43 return -1;
44 cmds->names = tmp;
45 }
46 for (i = 0; i < old->cnt; i++)
47 cmds->names[cmds->cnt++] = old->names[i];
48 zfree(&old->names);
49 old->cnt = 0;
50 return 0;
51 }
52
help_unknown_cmd(const char * cmd)53 const char *help_unknown_cmd(const char *cmd)
54 {
55 unsigned int i, n = 0, best_similarity = 0;
56 struct cmdnames main_cmds, other_cmds;
57
58 memset(&main_cmds, 0, sizeof(main_cmds));
59 memset(&other_cmds, 0, sizeof(main_cmds));
60
61 perf_config(perf_unknown_cmd_config, NULL);
62
63 load_command_list("perf-", &main_cmds, &other_cmds);
64
65 if (add_cmd_list(&main_cmds, &other_cmds) < 0) {
66 fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
67 goto end;
68 }
69 qsort(main_cmds.names, main_cmds.cnt,
70 sizeof(main_cmds.names), cmdname_compare);
71 uniq(&main_cmds);
72
73 if (main_cmds.cnt) {
74 /* This reuses cmdname->len for similarity index */
75 for (i = 0; i < main_cmds.cnt; ++i)
76 main_cmds.names[i]->len =
77 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
78
79 qsort(main_cmds.names, main_cmds.cnt,
80 sizeof(*main_cmds.names), levenshtein_compare);
81
82 best_similarity = main_cmds.names[0]->len;
83 n = 1;
84 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
85 ++n;
86 }
87
88 if (autocorrect && n == 1) {
89 const char *assumed = main_cmds.names[0]->name;
90
91 main_cmds.names[0] = NULL;
92 clean_cmdnames(&main_cmds);
93 fprintf(stderr, "WARNING: You called a perf program named '%s', "
94 "which does not exist.\n"
95 "Continuing under the assumption that you meant '%s'\n",
96 cmd, assumed);
97 if (autocorrect > 0) {
98 fprintf(stderr, "in %0.1f seconds automatically...\n",
99 (float)autocorrect/10.0);
100 poll(NULL, 0, autocorrect * 100);
101 }
102 return assumed;
103 }
104
105 fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);
106
107 if (main_cmds.cnt && best_similarity < 6) {
108 fprintf(stderr, "\nDid you mean %s?\n",
109 n < 2 ? "this": "one of these");
110
111 for (i = 0; i < n; i++)
112 fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
113 }
114 end:
115 exit(1);
116 }
117