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 = 1; i < cmds->cnt; i++) {
  56                 if (!strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  57                         zfree(&cmds->names[i - 1]);
  58         }
  59         for (i = 0, j = 0; i < cmds->cnt; i++) {
  60                 if (cmds->names[i]) {
  61                         if (i == j)
  62                                 j++;
  63                         else
  64                                 cmds->names[j++] = cmds->names[i];
  65                 }
  66         }
  67         cmds->cnt = j;
  68         while (j < i)
  69                 cmds->names[j++] = NULL;
  70 }
  71
  72 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  73 {
  74         size_t ci, cj, ei;
  75         int cmp;
  76
  77         ci = cj = ei = 0;
  78         while (ci < cmds->cnt && ei < excludes->cnt) {
  79                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  80                 if (cmp < 0) {
  81                         if (ci == cj) {
  82                                 ci++;
  83                                 cj++;
  84                         } else {
  85                                 zfree(&cmds->names[cj]);
  86                                 cmds->names[cj++] = cmds->names[ci++];
  87                         }
  88                 } else if (cmp == 0) {
  89                         ci++;
  90                         ei++;
  91                 } else if (cmp > 0) {
  92                         ei++;
  93                 }
  94         }
  95         if (ci != cj) {
  96                 while (ci < cmds->cnt) {
  97                         zfree(&cmds->names[cj]);
  98                         cmds->names[cj++] = cmds->names[ci++];
  99                 }
 100         }
 101         for (ci = cj; ci < cmds->cnt; ci++)
 102                 zfree(&cmds->names[ci]);
 103         cmds->cnt = cj;
 104 }
 105
 106 static void get_term_dimensions(struct winsize *ws)
 107 {
 108         char *s = getenv("LINES");
 109
 110         if (s != NULL) {
 111                 ws->ws_row = atoi(s);
 112                 s = getenv("COLUMNS");
 113                 if (s != NULL) {
 114                         ws->ws_col = atoi(s);
 115                         if (ws->ws_row && ws->ws_col)
 116                                 return;
 117                 }
 118         }
 119 #ifdef TIOCGWINSZ
 120         if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
 121             ws->ws_row && ws->ws_col)
 122                 return;
 123 #endif
 124         ws->ws_row = 25;
 125         ws->ws_col = 80;
 126 }
 127
 128 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
 129 {
 130         int cols = 1, rows;
 131         int space = longest + 1; /* min 1 SP between words */
 132         struct winsize win;
 133         int max_cols;
 134         int i, j;
 135
 136         get_term_dimensions(&win);
 137         max_cols = win.ws_col - 1; /* don't print *on* the edge */
 138
 139         if (space < max_cols)
 140                 cols = max_cols / space;
 141         rows = (cmds->cnt + cols - 1) / cols;
 142
 143         for (i = 0; i < rows; i++) {
 144                 printf("  ");
 145
 146                 for (j = 0; j < cols; j++) {
 147                         unsigned int n = j * rows + i;
 148                         unsigned int size = space;
 149
 150                         if (n >= cmds->cnt)
 151                                 break;
 152                         if (j == cols-1 || n + rows >= cmds->cnt)
 153                                 size = 1;
 154                         printf("%-*s", size, cmds->names[n]->name);
 155                 }
 156                 putchar('\n');
 157         }
 158 }
 159
 160 static int is_executable(const char *name)
 161 {
 162         struct stat st;
 163
 164         if (stat(name, &st) || /* stat, not lstat */
 165             !S_ISREG(st.st_mode))
 166                 return 0;
 167
 168         return st.st_mode & S_IXUSR;
 169 }
 170
 171 static int has_extension(const char *filename, const char *ext)
 172 {
 173         size_t len = strlen(filename);
 174         size_t extlen = strlen(ext);
 175
 176         return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
 177 }
 178
 179 static void list_commands_in_dir(struct cmdnames *cmds,
 180                                          const char *path,
 181                                          const char *prefix)
 182 {
 183         int prefix_len;
 184         DIR *dir = opendir(path);
 185         struct dirent *de;
 186         char *buf = NULL;
 187
 188         if (!dir)
 189                 return;
 190         if (!prefix)
 191                 prefix = "perf-";
 192         prefix_len = strlen(prefix);
 193
 194         astrcatf(&buf, "%s/", path);
 195
 196         while ((de = readdir(dir)) != NULL) {
 197                 int entlen;
 198
 199                 if (!strstarts(de->d_name, prefix))
 200                         continue;
 201
 202                 astrcat(&buf, de->d_name);
 203                 if (!is_executable(buf))
 204                         continue;
 205
 206                 entlen = strlen(de->d_name) - prefix_len;
 207                 if (has_extension(de->d_name, ".exe"))
 208                         entlen -= 4;
 209
 210                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 211         }
 212         closedir(dir);
 213         free(buf);
 214 }
 215
 216 void load_command_list(const char *prefix,
 217                 struct cmdnames *main_cmds,
 218                 struct cmdnames *other_cmds)
 219 {
 220         const char *env_path = getenv("PATH");
 221         char *exec_path = get_argv_exec_path();
 222
 223         if (exec_path) {
 224                 list_commands_in_dir(main_cmds, exec_path, prefix);
 225                 qsort(main_cmds->names, main_cmds->cnt,
 226                       sizeof(*main_cmds->names), cmdname_compare);
 227                 uniq(main_cmds);
 228         }
 229
 230         if (env_path) {
 231                 char *paths, *path, *colon;
 232                 path = paths = strdup(env_path);
 233                 while (1) {
 234                         if ((colon = strchr(path, ':')))
 235                                 *colon = 0;
 236                         if (!exec_path || strcmp(path, exec_path))
 237                                 list_commands_in_dir(other_cmds, path, prefix);
 238
 239                         if (!colon)
 240                                 break;
 241                         path = colon + 1;
 242                 }
 243                 free(paths);
 244
 245                 qsort(other_cmds->names, other_cmds->cnt,
 246                       sizeof(*other_cmds->names), cmdname_compare);
 247                 uniq(other_cmds);
 248         }
 249         free(exec_path);
 250         exclude_cmds(other_cmds, main_cmds);
 251 }
 252
 253 void list_commands(const char *title, struct cmdnames *main_cmds,
 254                    struct cmdnames *other_cmds)
 255 {
 256         unsigned int i, longest = 0;
 257
 258         for (i = 0; i < main_cmds->cnt; i++)
 259                 if (longest < main_cmds->names[i]->len)
 260                         longest = main_cmds->names[i]->len;
 261         for (i = 0; i < other_cmds->cnt; i++)
 262                 if (longest < other_cmds->names[i]->len)
 263                         longest = other_cmds->names[i]->len;
 264
 265         if (main_cmds->cnt) {
 266                 char *exec_path = get_argv_exec_path();
 267                 printf("available %s in '%s'\n", title, exec_path);
 268                 printf("----------------");
 269                 mput_char('-', strlen(title) + strlen(exec_path));
 270                 putchar('\n');
 271                 pretty_print_string_list(main_cmds, longest);
 272                 putchar('\n');
 273                 free(exec_path);
 274         }
 275
 276         if (other_cmds->cnt) {
 277                 printf("%s available from elsewhere on your $PATH\n", title);
 278                 printf("---------------------------------------");
 279                 mput_char('-', strlen(title));
 280                 putchar('\n');
 281                 pretty_print_string_list(other_cmds, longest);
 282                 putchar('\n');
 283         }
 284 }
 285
 286 int is_in_cmdlist(struct cmdnames *c, const char *s)
 287 {
 288         unsigned int i;
 289
 290         for (i = 0; i < c->cnt; i++)
 291                 if (!strcmp(s, c->names[i]->name))
 292                         return 1;
 293         return 0;
 294 }