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                         if (ci == cj) {
  72                                 ci++;
  73                                 cj++;
  74                         } else {
  75                                 zfree(&cmds->names[cj]);
  76                                 cmds->names[cj++] = cmds->names[ci++];
  77                         }
  78                 } else if (cmp == 0) {
  79                         ci++;
  80                         ei++;
  81                 } else if (cmp > 0) {
  82                         ei++;
  83                 }
  84         }
  85         if (ci != cj) {
  86                 while (ci < cmds->cnt) {
  87                         zfree(&cmds->names[cj]);
  88                         cmds->names[cj++] = cmds->names[ci++];
  89                 }
  90         }
  91         for (ci = cj; ci < cmds->cnt; ci++)
  92                 zfree(&cmds->names[ci]);
  93         cmds->cnt = cj;
  94 }
  95
  96 static void get_term_dimensions(struct winsize *ws)
  97 {
  98         char *s = getenv("LINES");
  99
 100         if (s != NULL) {
 101                 ws->ws_row = atoi(s);
 102                 s = getenv("COLUMNS");
 103                 if (s != NULL) {
 104                         ws->ws_col = atoi(s);
 105                         if (ws->ws_row && ws->ws_col)
 106                                 return;
 107                 }
 108         }
 109 #ifdef TIOCGWINSZ
 110         if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
 111             ws->ws_row && ws->ws_col)
 112                 return;
 113 #endif
 114         ws->ws_row = 25;
 115         ws->ws_col = 80;
 116 }
 117
 118 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
 119 {
 120         int cols = 1, rows;
 121         int space = longest + 1; /* min 1 SP between words */
 122         struct winsize win;
 123         int max_cols;
 124         int i, j;
 125
 126         get_term_dimensions(&win);
 127         max_cols = win.ws_col - 1; /* don't print *on* the edge */
 128
 129         if (space < max_cols)
 130                 cols = max_cols / space;
 131         rows = (cmds->cnt + cols - 1) / cols;
 132
 133         for (i = 0; i < rows; i++) {
 134                 printf("  ");
 135
 136                 for (j = 0; j < cols; j++) {
 137                         unsigned int n = j * rows + i;
 138                         unsigned int size = space;
 139
 140                         if (n >= cmds->cnt)
 141                                 break;
 142                         if (j == cols-1 || n + rows >= cmds->cnt)
 143                                 size = 1;
 144                         printf("%-*s", size, cmds->names[n]->name);
 145                 }
 146                 putchar('\n');
 147         }
 148 }
 149
 150 static int is_executable(const char *name)
 151 {
 152         struct stat st;
 153
 154         if (stat(name, &st) || /* stat, not lstat */
 155             !S_ISREG(st.st_mode))
 156                 return 0;
 157
 158         return st.st_mode & S_IXUSR;
 159 }
 160
 161 static int has_extension(const char *filename, const char *ext)
 162 {
 163         size_t len = strlen(filename);
 164         size_t extlen = strlen(ext);
 165
 166         return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
 167 }
 168
 169 static void list_commands_in_dir(struct cmdnames *cmds,
 170                                          const char *path,
 171                                          const char *prefix)
 172 {
 173         int prefix_len;
 174         DIR *dir = opendir(path);
 175         struct dirent *de;
 176         char *buf = NULL;
 177
 178         if (!dir)
 179                 return;
 180         if (!prefix)
 181                 prefix = "perf-";
 182         prefix_len = strlen(prefix);
 183
 184         astrcatf(&buf, "%s/", path);
 185
 186         while ((de = readdir(dir)) != NULL) {
 187                 int entlen;
 188
 189                 if (!strstarts(de->d_name, prefix))
 190                         continue;
 191
 192                 astrcat(&buf, de->d_name);
 193                 if (!is_executable(buf))
 194                         continue;
 195
 196                 entlen = strlen(de->d_name) - prefix_len;
 197                 if (has_extension(de->d_name, ".exe"))
 198                         entlen -= 4;
 199
 200                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 201         }
 202         closedir(dir);
 203         free(buf);
 204 }
 205
 206 void load_command_list(const char *prefix,
 207                 struct cmdnames *main_cmds,
 208                 struct cmdnames *other_cmds)
 209 {
 210         const char *env_path = getenv("PATH");
 211         char *exec_path = get_argv_exec_path();
 212
 213         if (exec_path) {
 214                 list_commands_in_dir(main_cmds, exec_path, prefix);
 215                 qsort(main_cmds->names, main_cmds->cnt,
 216                       sizeof(*main_cmds->names), cmdname_compare);
 217                 uniq(main_cmds);
 218         }
 219
 220         if (env_path) {
 221                 char *paths, *path, *colon;
 222                 path = paths = strdup(env_path);
 223                 while (1) {
 224                         if ((colon = strchr(path, ':')))
 225                                 *colon = 0;
 226                         if (!exec_path || strcmp(path, exec_path))
 227                                 list_commands_in_dir(other_cmds, path, prefix);
 228
 229                         if (!colon)
 230                                 break;
 231                         path = colon + 1;
 232                 }
 233                 free(paths);
 234
 235                 qsort(other_cmds->names, other_cmds->cnt,
 236                       sizeof(*other_cmds->names), cmdname_compare);
 237                 uniq(other_cmds);
 238         }
 239         free(exec_path);
 240         exclude_cmds(other_cmds, main_cmds);
 241 }
 242
 243 void list_commands(const char *title, struct cmdnames *main_cmds,
 244                    struct cmdnames *other_cmds)
 245 {
 246         unsigned int i, longest = 0;
 247
 248         for (i = 0; i < main_cmds->cnt; i++)
 249                 if (longest < main_cmds->names[i]->len)
 250                         longest = main_cmds->names[i]->len;
 251         for (i = 0; i < other_cmds->cnt; i++)
 252                 if (longest < other_cmds->names[i]->len)
 253                         longest = other_cmds->names[i]->len;
 254
 255         if (main_cmds->cnt) {
 256                 char *exec_path = get_argv_exec_path();
 257                 printf("available %s in '%s'\n", title, exec_path);
 258                 printf("----------------");
 259                 mput_char('-', strlen(title) + strlen(exec_path));
 260                 putchar('\n');
 261                 pretty_print_string_list(main_cmds, longest);
 262                 putchar('\n');
 263                 free(exec_path);
 264         }
 265
 266         if (other_cmds->cnt) {
 267                 printf("%s available from elsewhere on your $PATH\n", title);
 268                 printf("---------------------------------------");
 269                 mput_char('-', strlen(title));
 270                 putchar('\n');
 271                 pretty_print_string_list(other_cmds, longest);
 272                 putchar('\n');
 273         }
 274 }
 275
 276 int is_in_cmdlist(struct cmdnames *c, const char *s)
 277 {
 278         unsigned int i;
 279
 280         for (i = 0; i < c->cnt; i++)
 281                 if (!strcmp(s, c->names[i]->name))
 282                         return 1;
 283         return 0;
 284 }