tools/lib/subcmd/help.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <linux/string.h>
   6 #include <termios.h>
   7 #include <sys/ioctl.h>
   8 #include <sys/types.h>
   9 #include <sys/stat.h>
  10 #include <unistd.h>
  11 #include <dirent.h>
  12 #include "subcmd-util.h"
  13 #include "help.h"
  14 #include "exec-cmd.h"
  15
  16 void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
  17 {
  18         struct cmdname *ent = malloc(sizeof(*ent) + len + 1);
  19         if (!ent)
  20                 return;
  21
  22         ent->len = len;
  23         memcpy(ent->name, name, len);
  24         ent->name[len] = 0;
  25
  26         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  27         cmds->names[cmds->cnt++] = ent;
  28 }
  29
  30 void clean_cmdnames(struct cmdnames *cmds)
  31 {
  32         unsigned int i;
  33
  34         for (i = 0; i < cmds->cnt; ++i)
  35                 zfree(&cmds->names[i]);
  36         zfree(&cmds->names);
  37         cmds->cnt = 0;
  38         cmds->alloc = 0;
  39 }
  40
  41 int cmdname_compare(const void *a_, const void *b_)
  42 {
  43         struct cmdname *a = *(struct cmdname **)a_;
  44         struct cmdname *b = *(struct cmdname **)b_;
  45         return strcmp(a->name, b->name);
  46 }
  47
  48 void uniq(struct cmdnames *cmds)
  49 {
  50         unsigned int i, j;
  51
  52         if (!cmds->cnt)
  53                 return;
  54
  55         for (i = j = 1; i < cmds->cnt; i++)
  56                 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  57                         cmds->names[j++] = cmds->names[i];
  58
  59         cmds->cnt = j;
  60 }
  61
  62 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  63 {
  64         size_t ci, cj, ei;
  65         int cmp;
  66
  67         ci = cj = ei = 0;
  68         while (ci < cmds->cnt && ei < excludes->cnt) {
  69                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  70                 if (cmp < 0) {
  71                         zfree(&cmds->names[cj]);
  72                         cmds->names[cj++] = cmds->names[ci++];
  73                 } else if (cmp == 0) {
  74                         ci++;
  75                         ei++;
  76                 } else if (cmp > 0) {
  77                         ei++;
  78                 }
  79         }
  80
  81         while (ci < cmds->cnt) {
  82                 zfree(&cmds->names[cj]);
  83                 cmds->names[cj++] = cmds->names[ci++];
  84         }
  85         for (ci = cj; ci < cmds->cnt; ci++)
  86                 zfree(&cmds->names[ci]);
  87         cmds->cnt = cj;
  88 }
  89
  90 static void get_term_dimensions(struct winsize *ws)
  91 {
  92         char *s = getenv("LINES");
  93
  94         if (s != NULL) {
  95                 ws->ws_row = atoi(s);
  96                 s = getenv("COLUMNS");
  97                 if (s != NULL) {
  98                         ws->ws_col = atoi(s);
  99                         if (ws->ws_row && ws->ws_col)
 100                                 return;
 101                 }
 102         }
 103 #ifdef TIOCGWINSZ
 104         if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
 105             ws->ws_row && ws->ws_col)
 106                 return;
 107 #endif
 108         ws->ws_row = 25;
 109         ws->ws_col = 80;
 110 }
 111
 112 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
 113 {
 114         int cols = 1, rows;
 115         int space = longest + 1; /* min 1 SP between words */
 116         struct winsize win;
 117         int max_cols;
 118         int i, j;
 119
 120         get_term_dimensions(&win);
 121         max_cols = win.ws_col - 1; /* don't print *on* the edge */
 122
 123         if (space < max_cols)
 124                 cols = max_cols / space;
 125         rows = (cmds->cnt + cols - 1) / cols;
 126
 127         for (i = 0; i < rows; i++) {
 128                 printf("  ");
 129
 130                 for (j = 0; j < cols; j++) {
 131                         unsigned int n = j * rows + i;
 132                         unsigned int size = space;
 133
 134                         if (n >= cmds->cnt)
 135                                 break;
 136                         if (j == cols-1 || n + rows >= cmds->cnt)
 137                                 size = 1;
 138                         printf("%-*s", size, cmds->names[n]->name);
 139                 }
 140                 putchar('\n');
 141         }
 142 }
 143
 144 static int is_executable(const char *name)
 145 {
 146         struct stat st;
 147
 148         if (stat(name, &st) || /* stat, not lstat */
 149             !S_ISREG(st.st_mode))
 150                 return 0;
 151
 152         return st.st_mode & S_IXUSR;
 153 }
 154
 155 static int has_extension(const char *filename, const char *ext)
 156 {
 157         size_t len = strlen(filename);
 158         size_t extlen = strlen(ext);
 159
 160         return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
 161 }
 162
 163 static void list_commands_in_dir(struct cmdnames *cmds,
 164                                          const char *path,
 165                                          const char *prefix)
 166 {
 167         int prefix_len;
 168         DIR *dir = opendir(path);
 169         struct dirent *de;
 170         char *buf = NULL;
 171
 172         if (!dir)
 173                 return;
 174         if (!prefix)
 175                 prefix = "perf-";
 176         prefix_len = strlen(prefix);
 177
 178         astrcatf(&buf, "%s/", path);
 179
 180         while ((de = readdir(dir)) != NULL) {
 181                 int entlen;
 182
 183                 if (!strstarts(de->d_name, prefix))
 184                         continue;
 185
 186                 astrcat(&buf, de->d_name);
 187                 if (!is_executable(buf))
 188                         continue;
 189
 190                 entlen = strlen(de->d_name) - prefix_len;
 191                 if (has_extension(de->d_name, ".exe"))
 192                         entlen -= 4;
 193
 194                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 195         }
 196         closedir(dir);
 197         free(buf);
 198 }
 199
 200 void load_command_list(const char *prefix,
 201                 struct cmdnames *main_cmds,
 202                 struct cmdnames *other_cmds)
 203 {
 204         const char *env_path = getenv("PATH");
 205         char *exec_path = get_argv_exec_path();
 206
 207         if (exec_path) {
 208                 list_commands_in_dir(main_cmds, exec_path, prefix);
 209                 qsort(main_cmds->names, main_cmds->cnt,
 210                       sizeof(*main_cmds->names), cmdname_compare);
 211                 uniq(main_cmds);
 212         }
 213
 214         if (env_path) {
 215                 char *paths, *path, *colon;
 216                 path = paths = strdup(env_path);
 217                 while (1) {
 218                         if ((colon = strchr(path, ':')))
 219                                 *colon = 0;
 220                         if (!exec_path || strcmp(path, exec_path))
 221                                 list_commands_in_dir(other_cmds, path, prefix);
 222
 223                         if (!colon)
 224                                 break;
 225                         path = colon + 1;
 226                 }
 227                 free(paths);
 228
 229                 qsort(other_cmds->names, other_cmds->cnt,
 230                       sizeof(*other_cmds->names), cmdname_compare);
 231                 uniq(other_cmds);
 232         }
 233         free(exec_path);
 234         exclude_cmds(other_cmds, main_cmds);
 235 }
 236
 237 void list_commands(const char *title, struct cmdnames *main_cmds,
 238                    struct cmdnames *other_cmds)
 239 {
 240         unsigned int i, longest = 0;
 241
 242         for (i = 0; i < main_cmds->cnt; i++)
 243                 if (longest < main_cmds->names[i]->len)
 244                         longest = main_cmds->names[i]->len;
 245         for (i = 0; i < other_cmds->cnt; i++)
 246                 if (longest < other_cmds->names[i]->len)
 247                         longest = other_cmds->names[i]->len;
 248
 249         if (main_cmds->cnt) {
 250                 char *exec_path = get_argv_exec_path();
 251                 printf("available %s in '%s'\n", title, exec_path);
 252                 printf("----------------");
 253                 mput_char('-', strlen(title) + strlen(exec_path));
 254                 putchar('\n');
 255                 pretty_print_string_list(main_cmds, longest);
 256                 putchar('\n');
 257                 free(exec_path);
 258         }
 259
 260         if (other_cmds->cnt) {
 261                 printf("%s available from elsewhere on your $PATH\n", title);
 262                 printf("---------------------------------------");
 263                 mput_char('-', strlen(title));
 264                 putchar('\n');
 265                 pretty_print_string_list(other_cmds, longest);
 266                 putchar('\n');
 267         }
 268 }
 269
 270 int is_in_cmdlist(struct cmdnames *c, const char *s)
 271 {
 272         unsigned int i;
 273
 274         for (i = 0; i < c->cnt; i++)
 275                 if (!strcmp(s, c->names[i]->name))
 276                         return 1;
 277         return 0;
 278 }