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 = 1; i < cmds->cnt; i++) {
  54                 if (!strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  55                         zfree(&cmds->names[i - 1]);
  56         }
  57         for (i = 0, j = 0; i < cmds->cnt; i++) {
  58                 if (cmds->names[i]) {
  59                         if (i == j)
  60                                 j++;
  61                         else
  62                                 cmds->names[j++] = cmds->names[i];
  63                 }
  64         }
  65         cmds->cnt = j;
  66         while (j < i)
  67                 cmds->names[j++] = NULL;
  68 }
  69
  70 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  71 {
  72         size_t ci, cj, ei;
  73         int cmp;
  74
  75         ci = cj = ei = 0;
  76         while (ci < cmds->cnt && ei < excludes->cnt) {
  77                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  78                 if (cmp < 0) {
  79                         cmds->names[cj++] = cmds->names[ci++];
  80                 } else if (cmp == 0) {
  81                         ci++;
  82                         ei++;
  83                 } else if (cmp > 0) {
  84                         ei++;
  85                 }
  86         }
  87
  88         while (ci < cmds->cnt)
  89                 cmds->names[cj++] = cmds->names[ci++];
  90
  91         cmds->cnt = cj;
  92 }
  93
  94 static void get_term_dimensions(struct winsize *ws)
  95 {
  96         char *s = getenv("LINES");
  97
  98         if (s != NULL) {
  99                 ws->ws_row = atoi(s);
 100                 s = getenv("COLUMNS");
 101                 if (s != NULL) {
 102                         ws->ws_col = atoi(s);
 103                         if (ws->ws_row && ws->ws_col)
 104                                 return;
 105                 }
 106         }
 107 #ifdef TIOCGWINSZ
 108         if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
 109             ws->ws_row && ws->ws_col)
 110                 return;
 111 #endif
 112         ws->ws_row = 25;
 113         ws->ws_col = 80;
 114 }
 115
 116 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
 117 {
 118         int cols = 1, rows;
 119         int space = longest + 1; /* min 1 SP between words */
 120         struct winsize win;
 121         int max_cols;
 122         int i, j;
 123
 124         get_term_dimensions(&win);
 125         max_cols = win.ws_col - 1; /* don't print *on* the edge */
 126
 127         if (space < max_cols)
 128                 cols = max_cols / space;
 129         rows = (cmds->cnt + cols - 1) / cols;
 130
 131         for (i = 0; i < rows; i++) {
 132                 printf("  ");
 133
 134                 for (j = 0; j < cols; j++) {
 135                         unsigned int n = j * rows + i;
 136                         unsigned int size = space;
 137
 138                         if (n >= cmds->cnt)
 139                                 break;
 140                         if (j == cols-1 || n + rows >= cmds->cnt)
 141                                 size = 1;
 142                         printf("%-*s", size, cmds->names[n]->name);
 143                 }
 144                 putchar('\n');
 145         }
 146 }
 147
 148 static int is_executable(const char *name)
 149 {
 150         struct stat st;
 151
 152         if (stat(name, &st) || /* stat, not lstat */
 153             !S_ISREG(st.st_mode))
 154                 return 0;
 155
 156         return st.st_mode & S_IXUSR;
 157 }
 158
 159 static int has_extension(const char *filename, const char *ext)
 160 {
 161         size_t len = strlen(filename);
 162         size_t extlen = strlen(ext);
 163
 164         return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
 165 }
 166
 167 static void list_commands_in_dir(struct cmdnames *cmds,
 168                                          const char *path,
 169                                          const char *prefix)
 170 {
 171         int prefix_len;
 172         DIR *dir = opendir(path);
 173         struct dirent *de;
 174         char *buf = NULL;
 175
 176         if (!dir)
 177                 return;
 178         if (!prefix)
 179                 prefix = "perf-";
 180         prefix_len = strlen(prefix);
 181
 182         astrcatf(&buf, "%s/", path);
 183
 184         while ((de = readdir(dir)) != NULL) {
 185                 int entlen;
 186
 187                 if (!strstarts(de->d_name, prefix))
 188                         continue;
 189
 190                 astrcat(&buf, de->d_name);
 191                 if (!is_executable(buf))
 192                         continue;
 193
 194                 entlen = strlen(de->d_name) - prefix_len;
 195                 if (has_extension(de->d_name, ".exe"))
 196                         entlen -= 4;
 197
 198                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 199         }
 200         closedir(dir);
 201         free(buf);
 202 }
 203
 204 void load_command_list(const char *prefix,
 205                 struct cmdnames *main_cmds,
 206                 struct cmdnames *other_cmds)
 207 {
 208         const char *env_path = getenv("PATH");
 209         char *exec_path = get_argv_exec_path();
 210
 211         if (exec_path) {
 212                 list_commands_in_dir(main_cmds, exec_path, prefix);
 213                 qsort(main_cmds->names, main_cmds->cnt,
 214                       sizeof(*main_cmds->names), cmdname_compare);
 215                 uniq(main_cmds);
 216         }
 217
 218         if (env_path) {
 219                 char *paths, *path, *colon;
 220                 path = paths = strdup(env_path);
 221                 while (1) {
 222                         if ((colon = strchr(path, ':')))
 223                                 *colon = 0;
 224                         if (!exec_path || strcmp(path, exec_path))
 225                                 list_commands_in_dir(other_cmds, path, prefix);
 226
 227                         if (!colon)
 228                                 break;
 229                         path = colon + 1;
 230                 }
 231                 free(paths);
 232
 233                 qsort(other_cmds->names, other_cmds->cnt,
 234                       sizeof(*other_cmds->names), cmdname_compare);
 235                 uniq(other_cmds);
 236         }
 237         free(exec_path);
 238         exclude_cmds(other_cmds, main_cmds);
 239 }
 240
 241 void list_commands(const char *title, struct cmdnames *main_cmds,
 242                    struct cmdnames *other_cmds)
 243 {
 244         unsigned int i, longest = 0;
 245
 246         for (i = 0; i < main_cmds->cnt; i++)
 247                 if (longest < main_cmds->names[i]->len)
 248                         longest = main_cmds->names[i]->len;
 249         for (i = 0; i < other_cmds->cnt; i++)
 250                 if (longest < other_cmds->names[i]->len)
 251                         longest = other_cmds->names[i]->len;
 252
 253         if (main_cmds->cnt) {
 254                 char *exec_path = get_argv_exec_path();
 255                 printf("available %s in '%s'\n", title, exec_path);
 256                 printf("----------------");
 257                 mput_char('-', strlen(title) + strlen(exec_path));
 258                 putchar('\n');
 259                 pretty_print_string_list(main_cmds, longest);
 260                 putchar('\n');
 261                 free(exec_path);
 262         }
 263
 264         if (other_cmds->cnt) {
 265                 printf("%s available from elsewhere on your $PATH\n", title);
 266                 printf("---------------------------------------");
 267                 mput_char('-', strlen(title));
 268                 putchar('\n');
 269                 pretty_print_string_list(other_cmds, longest);
 270                 putchar('\n');
 271         }
 272 }
 273
 274 int is_in_cmdlist(struct cmdnames *c, const char *s)
 275 {
 276         unsigned int i;
 277
 278         for (i = 0; i < c->cnt; i++)
 279                 if (!strcmp(s, c->names[i]->name))
 280                         return 1;
 281         return 0;
 282 }