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 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 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 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 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