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
16void 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
30void 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
41int 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
48void 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
72void 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
106static 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
128static 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(ws: &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
160static 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
171static 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(p: filename + len - extlen, q: ext, size: extlen);
177}
178
179static 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(str: de->d_name, prefix))
200 continue;
201
202 astrcat(out: &buf, add: de->d_name);
203 if (!is_executable(name: buf))
204 continue;
205
206 entlen = strlen(de->d_name) - prefix_len;
207 if (has_extension(filename: de->d_name, ext: ".exe"))
208 entlen -= 4;
209
210 add_cmdname(cmds, name: de->d_name + prefix_len, len: entlen);
211 }
212 closedir(dir);
213 free(buf);
214}
215
216void 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(cmds: main_cmds, path: exec_path, prefix);
225 qsort(main_cmds->names, main_cmds->cnt,
226 sizeof(*main_cmds->names), cmdname_compare);
227 uniq(cmds: 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(cmds: 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(cmds: other_cmds);
248 }
249 free(exec_path);
250 exclude_cmds(cmds: other_cmds, excludes: main_cmds);
251}
252
253void 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(c: '-', strlen(title) + strlen(exec_path));
270 putchar('\n');
271 pretty_print_string_list(cmds: 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(c: '-', strlen(title));
280 putchar('\n');
281 pretty_print_string_list(cmds: other_cmds, longest);
282 putchar('\n');
283 }
284}
285
286int 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}
295

source code of linux/tools/lib/subcmd/help.c