xref: /openbmc/linux/tools/lib/subcmd/help.c (revision 132db935)
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 = j = 1; i < cmds->cnt; i++)
54 		if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
55 			cmds->names[j++] = cmds->names[i];
56 
57 	cmds->cnt = j;
58 }
59 
60 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
61 {
62 	size_t ci, cj, ei;
63 	int cmp;
64 
65 	ci = cj = ei = 0;
66 	while (ci < cmds->cnt && ei < excludes->cnt) {
67 		cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
68 		if (cmp < 0)
69 			cmds->names[cj++] = cmds->names[ci++];
70 		else if (cmp == 0)
71 			ci++, ei++;
72 		else if (cmp > 0)
73 			ei++;
74 	}
75 
76 	while (ci < cmds->cnt)
77 		cmds->names[cj++] = cmds->names[ci++];
78 
79 	cmds->cnt = cj;
80 }
81 
82 static void get_term_dimensions(struct winsize *ws)
83 {
84 	char *s = getenv("LINES");
85 
86 	if (s != NULL) {
87 		ws->ws_row = atoi(s);
88 		s = getenv("COLUMNS");
89 		if (s != NULL) {
90 			ws->ws_col = atoi(s);
91 			if (ws->ws_row && ws->ws_col)
92 				return;
93 		}
94 	}
95 #ifdef TIOCGWINSZ
96 	if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
97 	    ws->ws_row && ws->ws_col)
98 		return;
99 #endif
100 	ws->ws_row = 25;
101 	ws->ws_col = 80;
102 }
103 
104 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
105 {
106 	int cols = 1, rows;
107 	int space = longest + 1; /* min 1 SP between words */
108 	struct winsize win;
109 	int max_cols;
110 	int i, j;
111 
112 	get_term_dimensions(&win);
113 	max_cols = win.ws_col - 1; /* don't print *on* the edge */
114 
115 	if (space < max_cols)
116 		cols = max_cols / space;
117 	rows = (cmds->cnt + cols - 1) / cols;
118 
119 	for (i = 0; i < rows; i++) {
120 		printf("  ");
121 
122 		for (j = 0; j < cols; j++) {
123 			unsigned int n = j * rows + i;
124 			unsigned int size = space;
125 
126 			if (n >= cmds->cnt)
127 				break;
128 			if (j == cols-1 || n + rows >= cmds->cnt)
129 				size = 1;
130 			printf("%-*s", size, cmds->names[n]->name);
131 		}
132 		putchar('\n');
133 	}
134 }
135 
136 static int is_executable(const char *name)
137 {
138 	struct stat st;
139 
140 	if (stat(name, &st) || /* stat, not lstat */
141 	    !S_ISREG(st.st_mode))
142 		return 0;
143 
144 	return st.st_mode & S_IXUSR;
145 }
146 
147 static int has_extension(const char *filename, const char *ext)
148 {
149 	size_t len = strlen(filename);
150 	size_t extlen = strlen(ext);
151 
152 	return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
153 }
154 
155 static void list_commands_in_dir(struct cmdnames *cmds,
156 					 const char *path,
157 					 const char *prefix)
158 {
159 	int prefix_len;
160 	DIR *dir = opendir(path);
161 	struct dirent *de;
162 	char *buf = NULL;
163 
164 	if (!dir)
165 		return;
166 	if (!prefix)
167 		prefix = "perf-";
168 	prefix_len = strlen(prefix);
169 
170 	astrcatf(&buf, "%s/", path);
171 
172 	while ((de = readdir(dir)) != NULL) {
173 		int entlen;
174 
175 		if (!strstarts(de->d_name, prefix))
176 			continue;
177 
178 		astrcat(&buf, de->d_name);
179 		if (!is_executable(buf))
180 			continue;
181 
182 		entlen = strlen(de->d_name) - prefix_len;
183 		if (has_extension(de->d_name, ".exe"))
184 			entlen -= 4;
185 
186 		add_cmdname(cmds, de->d_name + prefix_len, entlen);
187 	}
188 	closedir(dir);
189 	free(buf);
190 }
191 
192 void load_command_list(const char *prefix,
193 		struct cmdnames *main_cmds,
194 		struct cmdnames *other_cmds)
195 {
196 	const char *env_path = getenv("PATH");
197 	char *exec_path = get_argv_exec_path();
198 
199 	if (exec_path) {
200 		list_commands_in_dir(main_cmds, exec_path, prefix);
201 		qsort(main_cmds->names, main_cmds->cnt,
202 		      sizeof(*main_cmds->names), cmdname_compare);
203 		uniq(main_cmds);
204 	}
205 
206 	if (env_path) {
207 		char *paths, *path, *colon;
208 		path = paths = strdup(env_path);
209 		while (1) {
210 			if ((colon = strchr(path, ':')))
211 				*colon = 0;
212 			if (!exec_path || strcmp(path, exec_path))
213 				list_commands_in_dir(other_cmds, path, prefix);
214 
215 			if (!colon)
216 				break;
217 			path = colon + 1;
218 		}
219 		free(paths);
220 
221 		qsort(other_cmds->names, other_cmds->cnt,
222 		      sizeof(*other_cmds->names), cmdname_compare);
223 		uniq(other_cmds);
224 	}
225 	free(exec_path);
226 	exclude_cmds(other_cmds, main_cmds);
227 }
228 
229 void list_commands(const char *title, struct cmdnames *main_cmds,
230 		   struct cmdnames *other_cmds)
231 {
232 	unsigned int i, longest = 0;
233 
234 	for (i = 0; i < main_cmds->cnt; i++)
235 		if (longest < main_cmds->names[i]->len)
236 			longest = main_cmds->names[i]->len;
237 	for (i = 0; i < other_cmds->cnt; i++)
238 		if (longest < other_cmds->names[i]->len)
239 			longest = other_cmds->names[i]->len;
240 
241 	if (main_cmds->cnt) {
242 		char *exec_path = get_argv_exec_path();
243 		printf("available %s in '%s'\n", title, exec_path);
244 		printf("----------------");
245 		mput_char('-', strlen(title) + strlen(exec_path));
246 		putchar('\n');
247 		pretty_print_string_list(main_cmds, longest);
248 		putchar('\n');
249 		free(exec_path);
250 	}
251 
252 	if (other_cmds->cnt) {
253 		printf("%s available from elsewhere on your $PATH\n", title);
254 		printf("---------------------------------------");
255 		mput_char('-', strlen(title));
256 		putchar('\n');
257 		pretty_print_string_list(other_cmds, longest);
258 		putchar('\n');
259 	}
260 }
261 
262 int is_in_cmdlist(struct cmdnames *c, const char *s)
263 {
264 	unsigned int i;
265 
266 	for (i = 0; i < c->cnt; i++)
267 		if (!strcmp(s, c->names[i]->name))
268 			return 1;
269 	return 0;
270 }
271