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