xref: /openbmc/linux/tools/lib/subcmd/help.c (revision 4f6cce39)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <termios.h>
5 #include <sys/ioctl.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <unistd.h>
9 #include <dirent.h>
10 #include "subcmd-util.h"
11 #include "help.h"
12 #include "exec-cmd.h"
13 
14 void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
15 {
16 	struct cmdname *ent = malloc(sizeof(*ent) + len + 1);
17 
18 	ent->len = len;
19 	memcpy(ent->name, name, len);
20 	ent->name[len] = 0;
21 
22 	ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
23 	cmds->names[cmds->cnt++] = ent;
24 }
25 
26 void clean_cmdnames(struct cmdnames *cmds)
27 {
28 	unsigned int i;
29 
30 	for (i = 0; i < cmds->cnt; ++i)
31 		zfree(&cmds->names[i]);
32 	zfree(&cmds->names);
33 	cmds->cnt = 0;
34 	cmds->alloc = 0;
35 }
36 
37 int cmdname_compare(const void *a_, const void *b_)
38 {
39 	struct cmdname *a = *(struct cmdname **)a_;
40 	struct cmdname *b = *(struct cmdname **)b_;
41 	return strcmp(a->name, b->name);
42 }
43 
44 void uniq(struct cmdnames *cmds)
45 {
46 	unsigned int i, j;
47 
48 	if (!cmds->cnt)
49 		return;
50 
51 	for (i = j = 1; i < cmds->cnt; i++)
52 		if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
53 			cmds->names[j++] = cmds->names[i];
54 
55 	cmds->cnt = j;
56 }
57 
58 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
59 {
60 	size_t ci, cj, ei;
61 	int cmp;
62 
63 	ci = cj = ei = 0;
64 	while (ci < cmds->cnt && ei < excludes->cnt) {
65 		cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
66 		if (cmp < 0)
67 			cmds->names[cj++] = cmds->names[ci++];
68 		else if (cmp == 0)
69 			ci++, ei++;
70 		else if (cmp > 0)
71 			ei++;
72 	}
73 
74 	while (ci < cmds->cnt)
75 		cmds->names[cj++] = cmds->names[ci++];
76 
77 	cmds->cnt = cj;
78 }
79 
80 static void get_term_dimensions(struct winsize *ws)
81 {
82 	char *s = getenv("LINES");
83 
84 	if (s != NULL) {
85 		ws->ws_row = atoi(s);
86 		s = getenv("COLUMNS");
87 		if (s != NULL) {
88 			ws->ws_col = atoi(s);
89 			if (ws->ws_row && ws->ws_col)
90 				return;
91 		}
92 	}
93 #ifdef TIOCGWINSZ
94 	if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
95 	    ws->ws_row && ws->ws_col)
96 		return;
97 #endif
98 	ws->ws_row = 25;
99 	ws->ws_col = 80;
100 }
101 
102 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
103 {
104 	int cols = 1, rows;
105 	int space = longest + 1; /* min 1 SP between words */
106 	struct winsize win;
107 	int max_cols;
108 	int i, j;
109 
110 	get_term_dimensions(&win);
111 	max_cols = win.ws_col - 1; /* don't print *on* the edge */
112 
113 	if (space < max_cols)
114 		cols = max_cols / space;
115 	rows = (cmds->cnt + cols - 1) / cols;
116 
117 	for (i = 0; i < rows; i++) {
118 		printf("  ");
119 
120 		for (j = 0; j < cols; j++) {
121 			unsigned int n = j * rows + i;
122 			unsigned int size = space;
123 
124 			if (n >= cmds->cnt)
125 				break;
126 			if (j == cols-1 || n + rows >= cmds->cnt)
127 				size = 1;
128 			printf("%-*s", size, cmds->names[n]->name);
129 		}
130 		putchar('\n');
131 	}
132 }
133 
134 static int is_executable(const char *name)
135 {
136 	struct stat st;
137 
138 	if (stat(name, &st) || /* stat, not lstat */
139 	    !S_ISREG(st.st_mode))
140 		return 0;
141 
142 	return st.st_mode & S_IXUSR;
143 }
144 
145 static int has_extension(const char *filename, const char *ext)
146 {
147 	size_t len = strlen(filename);
148 	size_t extlen = strlen(ext);
149 
150 	return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
151 }
152 
153 static void list_commands_in_dir(struct cmdnames *cmds,
154 					 const char *path,
155 					 const char *prefix)
156 {
157 	int prefix_len;
158 	DIR *dir = opendir(path);
159 	struct dirent *de;
160 	char *buf = NULL;
161 
162 	if (!dir)
163 		return;
164 	if (!prefix)
165 		prefix = "perf-";
166 	prefix_len = strlen(prefix);
167 
168 	astrcatf(&buf, "%s/", path);
169 
170 	while ((de = readdir(dir)) != NULL) {
171 		int entlen;
172 
173 		if (prefixcmp(de->d_name, prefix))
174 			continue;
175 
176 		astrcat(&buf, de->d_name);
177 		if (!is_executable(buf))
178 			continue;
179 
180 		entlen = strlen(de->d_name) - prefix_len;
181 		if (has_extension(de->d_name, ".exe"))
182 			entlen -= 4;
183 
184 		add_cmdname(cmds, de->d_name + prefix_len, entlen);
185 	}
186 	closedir(dir);
187 	free(buf);
188 }
189 
190 void load_command_list(const char *prefix,
191 		struct cmdnames *main_cmds,
192 		struct cmdnames *other_cmds)
193 {
194 	const char *env_path = getenv("PATH");
195 	char *exec_path = get_argv_exec_path();
196 
197 	if (exec_path) {
198 		list_commands_in_dir(main_cmds, exec_path, prefix);
199 		qsort(main_cmds->names, main_cmds->cnt,
200 		      sizeof(*main_cmds->names), cmdname_compare);
201 		uniq(main_cmds);
202 	}
203 
204 	if (env_path) {
205 		char *paths, *path, *colon;
206 		path = paths = strdup(env_path);
207 		while (1) {
208 			if ((colon = strchr(path, ':')))
209 				*colon = 0;
210 			if (!exec_path || strcmp(path, exec_path))
211 				list_commands_in_dir(other_cmds, path, prefix);
212 
213 			if (!colon)
214 				break;
215 			path = colon + 1;
216 		}
217 		free(paths);
218 
219 		qsort(other_cmds->names, other_cmds->cnt,
220 		      sizeof(*other_cmds->names), cmdname_compare);
221 		uniq(other_cmds);
222 	}
223 	free(exec_path);
224 	exclude_cmds(other_cmds, main_cmds);
225 }
226 
227 void list_commands(const char *title, struct cmdnames *main_cmds,
228 		   struct cmdnames *other_cmds)
229 {
230 	unsigned int i, longest = 0;
231 
232 	for (i = 0; i < main_cmds->cnt; i++)
233 		if (longest < main_cmds->names[i]->len)
234 			longest = main_cmds->names[i]->len;
235 	for (i = 0; i < other_cmds->cnt; i++)
236 		if (longest < other_cmds->names[i]->len)
237 			longest = other_cmds->names[i]->len;
238 
239 	if (main_cmds->cnt) {
240 		char *exec_path = get_argv_exec_path();
241 		printf("available %s in '%s'\n", title, exec_path);
242 		printf("----------------");
243 		mput_char('-', strlen(title) + strlen(exec_path));
244 		putchar('\n');
245 		pretty_print_string_list(main_cmds, longest);
246 		putchar('\n');
247 		free(exec_path);
248 	}
249 
250 	if (other_cmds->cnt) {
251 		printf("%s available from elsewhere on your $PATH\n", title);
252 		printf("---------------------------------------");
253 		mput_char('-', strlen(title));
254 		putchar('\n');
255 		pretty_print_string_list(other_cmds, longest);
256 		putchar('\n');
257 	}
258 }
259 
260 int is_in_cmdlist(struct cmdnames *c, const char *s)
261 {
262 	unsigned int i;
263 
264 	for (i = 0; i < c->cnt; i++)
265 		if (!strcmp(s, c->names[i]->name))
266 			return 1;
267 	return 0;
268 }
269