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(&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(filename + len - extlen, ext, 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(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
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(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
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('-', 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
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