kernel/tools/perf/util/help.c

   1 #include "cache.h"
   2 #include "../builtin.h"
   3 #include "exec_cmd.h"
   4 #include "levenshtein.h"
   5 #include "help.h"
   6 #include <termios.h>
   7
   8 void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
   9 {
  10         struct cmdname *ent = malloc(sizeof(*ent) + len + 1);
  11
  12         ent->len = len;
  13         memcpy(ent->name, name, len);
  14         ent->name[len] = 0;
  15
  16         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  17         cmds->names[cmds->cnt++] = ent;
  18 }
  19
  20 static void clean_cmdnames(struct cmdnames *cmds)
  21 {
  22         unsigned int i;
  23
  24         for (i = 0; i < cmds->cnt; ++i)
  25                 zfree(&cmds->names[i]);
  26         zfree(&cmds->names);
  27         cmds->cnt = 0;
  28         cmds->alloc = 0;
  29 }
  30
  31 static int cmdname_compare(const void *a_, const void *b_)
  32 {
  33         struct cmdname *a = *(struct cmdname **)a_;
  34         struct cmdname *b = *(struct cmdname **)b_;
  35         return strcmp(a->name, b->name);
  36 }
  37
  38 static void uniq(struct cmdnames *cmds)
  39 {
  40         unsigned int i, j;
  41
  42         if (!cmds->cnt)
  43                 return;
  44
  45         for (i = j = 1; i < cmds->cnt; i++)
  46                 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  47                         cmds->names[j++] = cmds->names[i];
  48
  49         cmds->cnt = j;
  50 }
  51
  52 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  53 {
  54         size_t ci, cj, ei;
  55         int cmp;
  56
  57         ci = cj = ei = 0;
  58         while (ci < cmds->cnt && ei < excludes->cnt) {
  59                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  60                 if (cmp < 0)
  61                         cmds->names[cj++] = cmds->names[ci++];
  62                 else if (cmp == 0)
  63                         ci++, ei++;
  64                 else if (cmp > 0)
  65                         ei++;
  66         }
  67
  68         while (ci < cmds->cnt)
  69                 cmds->names[cj++] = cmds->names[ci++];
  70
  71         cmds->cnt = cj;
  72 }
  73
  74 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
  75 {
  76         int cols = 1, rows;
  77         int space = longest + 1; /* min 1 SP between words */
  78         struct winsize win;
  79         int max_cols;
  80         int i, j;
  81
  82         get_term_dimensions(&win);
  83         max_cols = win.ws_col - 1; /* don't print *on* the edge */
  84
  85         if (space < max_cols)
  86                 cols = max_cols / space;
  87         rows = (cmds->cnt + cols - 1) / cols;
  88
  89         for (i = 0; i < rows; i++) {
  90                 printf("  ");
  91
  92                 for (j = 0; j < cols; j++) {
  93                         unsigned int n = j * rows + i;
  94                         unsigned int size = space;
  95
  96                         if (n >= cmds->cnt)
  97                                 break;
  98                         if (j == cols-1 || n + rows >= cmds->cnt)
  99                                 size = 1;
 100                         printf("%-*s", size, cmds->names[n]->name);
 101                 }
 102                 putchar('\n');
 103         }
 104 }
 105
 106 static int is_executable(const char *name)
 107 {
 108         struct stat st;
 109
 110         if (stat(name, &st) || /* stat, not lstat */
 111             !S_ISREG(st.st_mode))
 112                 return 0;
 113
 114         return st.st_mode & S_IXUSR;
 115 }
 116
 117 static void list_commands_in_dir(struct cmdnames *cmds,
 118                                          const char *path,
 119                                          const char *prefix)
 120 {
 121         int prefix_len;
 122         DIR *dir = opendir(path);
 123         struct dirent *de;
 124         struct strbuf buf = STRBUF_INIT;
 125         int len;
 126
 127         if (!dir)
 128                 return;
 129         if (!prefix)
 130                 prefix = "perf-";
 131         prefix_len = strlen(prefix);
 132
 133         strbuf_addf(&buf, "%s/", path);
 134         len = buf.len;
 135
 136         while ((de = readdir(dir)) != NULL) {
 137                 int entlen;
 138
 139                 if (prefixcmp(de->d_name, prefix))
 140                         continue;
 141
 142                 strbuf_setlen(&buf, len);
 143                 strbuf_addstr(&buf, de->d_name);
 144                 if (!is_executable(buf.buf))
 145                         continue;
 146
 147                 entlen = strlen(de->d_name) - prefix_len;
 148                 if (has_extension(de->d_name, ".exe"))
 149                         entlen -= 4;
 150
 151                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 152         }
 153         closedir(dir);
 154         strbuf_release(&buf);
 155 }
 156
 157 void load_command_list(const char *prefix,
 158                 struct cmdnames *main_cmds,
 159                 struct cmdnames *other_cmds)
 160 {
 161         const char *env_path = getenv("PATH");
 162         const char *exec_path = perf_exec_path();
 163
 164         if (exec_path) {
 165                 list_commands_in_dir(main_cmds, exec_path, prefix);
 166                 qsort(main_cmds->names, main_cmds->cnt,
 167                       sizeof(*main_cmds->names), cmdname_compare);
 168                 uniq(main_cmds);
 169         }
 170
 171         if (env_path) {
 172                 char *paths, *path, *colon;
 173                 path = paths = strdup(env_path);
 174                 while (1) {
 175                         if ((colon = strchr(path, PATH_SEP)))
 176                                 *colon = 0;
 177                         if (!exec_path || strcmp(path, exec_path))
 178                                 list_commands_in_dir(other_cmds, path, prefix);
 179
 180                         if (!colon)
 181                                 break;
 182                         path = colon + 1;
 183                 }
 184                 free(paths);
 185
 186                 qsort(other_cmds->names, other_cmds->cnt,
 187                       sizeof(*other_cmds->names), cmdname_compare);
 188                 uniq(other_cmds);
 189         }
 190         exclude_cmds(other_cmds, main_cmds);
 191 }
 192
 193 void list_commands(const char *title, struct cmdnames *main_cmds,
 194                    struct cmdnames *other_cmds)
 195 {
 196         unsigned int i, longest = 0;
 197
 198         for (i = 0; i < main_cmds->cnt; i++)
 199                 if (longest < main_cmds->names[i]->len)
 200                         longest = main_cmds->names[i]->len;
 201         for (i = 0; i < other_cmds->cnt; i++)
 202                 if (longest < other_cmds->names[i]->len)
 203                         longest = other_cmds->names[i]->len;
 204
 205         if (main_cmds->cnt) {
 206                 const char *exec_path = perf_exec_path();
 207                 printf("available %s in '%s'\n", title, exec_path);
 208                 printf("----------------");
 209                 mput_char('-', strlen(title) + strlen(exec_path));
 210                 putchar('\n');
 211                 pretty_print_string_list(main_cmds, longest);
 212                 putchar('\n');
 213         }
 214
 215         if (other_cmds->cnt) {
 216                 printf("%s available from elsewhere on your $PATH\n", title);
 217                 printf("---------------------------------------");
 218                 mput_char('-', strlen(title));
 219                 putchar('\n');
 220                 pretty_print_string_list(other_cmds, longest);
 221                 putchar('\n');
 222         }
 223 }
 224
 225 int is_in_cmdlist(struct cmdnames *c, const char *s)
 226 {
 227         unsigned int i;
 228
 229         for (i = 0; i < c->cnt; i++)
 230                 if (!strcmp(s, c->names[i]->name))
 231                         return 1;
 232         return 0;
 233 }
 234
 235 static int autocorrect;
 236 static struct cmdnames aliases;
 237
 238 static int perf_unknown_cmd_config(const char *var, const char *value, void *cb)
 239 {
 240         if (!strcmp(var, "help.autocorrect"))
 241                 autocorrect = perf_config_int(var,value);
 242         /* Also use aliases for command lookup */
 243         if (!prefixcmp(var, "alias."))
 244                 add_cmdname(&aliases, var + 6, strlen(var + 6));
 245
 246         return perf_default_config(var, value, cb);
 247 }
 248
 249 static int levenshtein_compare(const void *p1, const void *p2)
 250 {
 251         const struct cmdname *const *c1 = p1, *const *c2 = p2;
 252         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 253         int l1 = (*c1)->len;
 254         int l2 = (*c2)->len;
 255         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 256 }
 257
 258 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 259 {
 260         unsigned int i;
 261
 262         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 263
 264         for (i = 0; i < old->cnt; i++)
 265                 cmds->names[cmds->cnt++] = old->names[i];
 266         zfree(&old->names);
 267         old->cnt = 0;
 268 }
 269
 270 const char *help_unknown_cmd(const char *cmd)
 271 {
 272         unsigned int i, n = 0, best_similarity = 0;
 273         struct cmdnames main_cmds, other_cmds;
 274
 275         memset(&main_cmds, 0, sizeof(main_cmds));
 276         memset(&other_cmds, 0, sizeof(main_cmds));
 277         memset(&aliases, 0, sizeof(aliases));
 278
 279         perf_config(perf_unknown_cmd_config, NULL);
 280
 281         load_command_list("perf-", &main_cmds, &other_cmds);
 282
 283         add_cmd_list(&main_cmds, &aliases);
 284         add_cmd_list(&main_cmds, &other_cmds);
 285         qsort(main_cmds.names, main_cmds.cnt,
 286               sizeof(main_cmds.names), cmdname_compare);
 287         uniq(&main_cmds);
 288
 289         if (main_cmds.cnt) {
 290                 /* This reuses cmdname->len for similarity index */
 291                 for (i = 0; i < main_cmds.cnt; ++i)
 292                         main_cmds.names[i]->len =
 293                                 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
 294
 295                 qsort(main_cmds.names, main_cmds.cnt,
 296                       sizeof(*main_cmds.names), levenshtein_compare);
 297
 298                 best_similarity = main_cmds.names[0]->len;
 299                 n = 1;
 300                 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
 301                         ++n;
 302         }
 303
 304         if (autocorrect && n == 1) {
 305                 const char *assumed = main_cmds.names[0]->name;
 306
 307                 main_cmds.names[0] = NULL;
 308                 clean_cmdnames(&main_cmds);
 309                 fprintf(stderr, "WARNING: You called a perf program named '%s', "
 310                         "which does not exist.\n"
 311                         "Continuing under the assumption that you meant '%s'\n",
 312                         cmd, assumed);
 313                 if (autocorrect > 0) {
 314                         fprintf(stderr, "in %0.1f seconds automatically...\n",
 315                                 (float)autocorrect/10.0);
 316                         poll(NULL, 0, autocorrect * 100);
 317                 }
 318                 return assumed;
 319         }
 320
 321         fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);
 322
 323         if (main_cmds.cnt && best_similarity < 6) {
 324                 fprintf(stderr, "\nDid you mean %s?\n",
 325                         n < 2 ? "this": "one of these");
 326
 327                 for (i = 0; i < n; i++)
 328                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 329         }
 330
 331         exit(1);
 332 }
 333
 334 int cmd_version(int argc __maybe_unused, const char **argv __maybe_unused,
 335                 const char *prefix __maybe_unused)
 336 {
 337         printf("perf version %s\n", perf_version_string);
 338         return 0;
 339 }