1 #include <dirent.h>
2 #include <limits.h>
3 #include <stdbool.h>
4 #include <stdlib.h>
5 #include <stdio.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <unistd.h>
9 #include "strlist.h"
10 #include <string.h>
11 #include "thread_map.h"
12 
13 /* Skip "." and ".." directories */
filter(const struct dirent * dir)14 static int filter(const struct dirent *dir)
15 {
16 	if (dir->d_name[0] == '.')
17 		return 0;
18 	else
19 		return 1;
20 }
21 
thread_map__new_by_pid(pid_t pid)22 struct thread_map *thread_map__new_by_pid(pid_t pid)
23 {
24 	struct thread_map *threads;
25 	char name[256];
26 	int items;
27 	struct dirent **namelist = NULL;
28 	int i;
29 
30 	sprintf(name, "/proc/%d/task", pid);
31 	items = scandir(name, &namelist, filter, NULL);
32 	if (items <= 0)
33 		return NULL;
34 
35 	threads = malloc(sizeof(*threads) + sizeof(pid_t) * items);
36 	if (threads != NULL) {
37 		for (i = 0; i < items; i++)
38 			threads->map[i] = atoi(namelist[i]->d_name);
39 		threads->nr = items;
40 	}
41 
42 	for (i=0; i<items; i++)
43 		free(namelist[i]);
44 	free(namelist);
45 
46 	return threads;
47 }
48 
thread_map__new_by_tid(pid_t tid)49 struct thread_map *thread_map__new_by_tid(pid_t tid)
50 {
51 	struct thread_map *threads = malloc(sizeof(*threads) + sizeof(pid_t));
52 
53 	if (threads != NULL) {
54 		threads->map[0] = tid;
55 		threads->nr	= 1;
56 	}
57 
58 	return threads;
59 }
60 
thread_map__new_by_uid(uid_t uid)61 struct thread_map *thread_map__new_by_uid(uid_t uid)
62 {
63 	DIR *proc;
64 	int max_threads = 32, items, i;
65 	char path[256];
66 	struct dirent dirent, *next, **namelist = NULL;
67 	struct thread_map *threads = malloc(sizeof(*threads) +
68 					    max_threads * sizeof(pid_t));
69 	if (threads == NULL)
70 		goto out;
71 
72 	proc = opendir("/proc");
73 	if (proc == NULL)
74 		goto out_free_threads;
75 
76 	threads->nr = 0;
77 
78 	while (!readdir_r(proc, &dirent, &next) && next) {
79 		char *end;
80 		bool grow = false;
81 		struct stat st;
82 		pid_t pid = strtol(dirent.d_name, &end, 10);
83 
84 		if (*end) /* only interested in proper numerical dirents */
85 			continue;
86 
87 		snprintf(path, sizeof(path), "/proc/%s", dirent.d_name);
88 
89 		if (stat(path, &st) != 0)
90 			continue;
91 
92 		if (st.st_uid != uid)
93 			continue;
94 
95 		snprintf(path, sizeof(path), "/proc/%d/task", pid);
96 		items = scandir(path, &namelist, filter, NULL);
97 		if (items <= 0)
98 			goto out_free_closedir;
99 
100 		while (threads->nr + items >= max_threads) {
101 			max_threads *= 2;
102 			grow = true;
103 		}
104 
105 		if (grow) {
106 			struct thread_map *tmp;
107 
108 			tmp = realloc(threads, (sizeof(*threads) +
109 						max_threads * sizeof(pid_t)));
110 			if (tmp == NULL)
111 				goto out_free_namelist;
112 
113 			threads = tmp;
114 		}
115 
116 		for (i = 0; i < items; i++)
117 			threads->map[threads->nr + i] = atoi(namelist[i]->d_name);
118 
119 		for (i = 0; i < items; i++)
120 			free(namelist[i]);
121 		free(namelist);
122 
123 		threads->nr += items;
124 	}
125 
126 out_closedir:
127 	closedir(proc);
128 out:
129 	return threads;
130 
131 out_free_threads:
132 	free(threads);
133 	return NULL;
134 
135 out_free_namelist:
136 	for (i = 0; i < items; i++)
137 		free(namelist[i]);
138 	free(namelist);
139 
140 out_free_closedir:
141 	free(threads);
142 	threads = NULL;
143 	goto out_closedir;
144 }
145 
thread_map__new(pid_t pid,pid_t tid,uid_t uid)146 struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid)
147 {
148 	if (pid != -1)
149 		return thread_map__new_by_pid(pid);
150 
151 	if (tid == -1 && uid != UINT_MAX)
152 		return thread_map__new_by_uid(uid);
153 
154 	return thread_map__new_by_tid(tid);
155 }
156 
thread_map__new_by_pid_str(const char * pid_str)157 static struct thread_map *thread_map__new_by_pid_str(const char *pid_str)
158 {
159 	struct thread_map *threads = NULL, *nt;
160 	char name[256];
161 	int items, total_tasks = 0;
162 	struct dirent **namelist = NULL;
163 	int i, j = 0;
164 	pid_t pid, prev_pid = INT_MAX;
165 	char *end_ptr;
166 	struct str_node *pos;
167 	struct strlist *slist = strlist__new(false, pid_str);
168 
169 	if (!slist)
170 		return NULL;
171 
172 	strlist__for_each(pos, slist) {
173 		pid = strtol(pos->s, &end_ptr, 10);
174 
175 		if (pid == INT_MIN || pid == INT_MAX ||
176 		    (*end_ptr != '\0' && *end_ptr != ','))
177 			goto out_free_threads;
178 
179 		if (pid == prev_pid)
180 			continue;
181 
182 		sprintf(name, "/proc/%d/task", pid);
183 		items = scandir(name, &namelist, filter, NULL);
184 		if (items <= 0)
185 			goto out_free_threads;
186 
187 		total_tasks += items;
188 		nt = realloc(threads, (sizeof(*threads) +
189 				       sizeof(pid_t) * total_tasks));
190 		if (nt == NULL)
191 			goto out_free_threads;
192 
193 		threads = nt;
194 
195 		if (threads) {
196 			for (i = 0; i < items; i++)
197 				threads->map[j++] = atoi(namelist[i]->d_name);
198 			threads->nr = total_tasks;
199 		}
200 
201 		for (i = 0; i < items; i++)
202 			free(namelist[i]);
203 		free(namelist);
204 
205 		if (!threads)
206 			break;
207 	}
208 
209 out:
210 	strlist__delete(slist);
211 	return threads;
212 
213 out_free_threads:
214 	free(threads);
215 	threads = NULL;
216 	goto out;
217 }
218 
thread_map__new_by_tid_str(const char * tid_str)219 static struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
220 {
221 	struct thread_map *threads = NULL, *nt;
222 	int ntasks = 0;
223 	pid_t tid, prev_tid = INT_MAX;
224 	char *end_ptr;
225 	struct str_node *pos;
226 	struct strlist *slist;
227 
228 	/* perf-stat expects threads to be generated even if tid not given */
229 	if (!tid_str) {
230 		threads = malloc(sizeof(*threads) + sizeof(pid_t));
231 		if (threads != NULL) {
232 			threads->map[0] = -1;
233 			threads->nr	= 1;
234 		}
235 		return threads;
236 	}
237 
238 	slist = strlist__new(false, tid_str);
239 	if (!slist)
240 		return NULL;
241 
242 	strlist__for_each(pos, slist) {
243 		tid = strtol(pos->s, &end_ptr, 10);
244 
245 		if (tid == INT_MIN || tid == INT_MAX ||
246 		    (*end_ptr != '\0' && *end_ptr != ','))
247 			goto out_free_threads;
248 
249 		if (tid == prev_tid)
250 			continue;
251 
252 		ntasks++;
253 		nt = realloc(threads, sizeof(*threads) + sizeof(pid_t) * ntasks);
254 
255 		if (nt == NULL)
256 			goto out_free_threads;
257 
258 		threads = nt;
259 		threads->map[ntasks - 1] = tid;
260 		threads->nr		 = ntasks;
261 	}
262 out:
263 	return threads;
264 
265 out_free_threads:
266 	free(threads);
267 	threads = NULL;
268 	goto out;
269 }
270 
thread_map__new_str(const char * pid,const char * tid,uid_t uid)271 struct thread_map *thread_map__new_str(const char *pid, const char *tid,
272 				       uid_t uid)
273 {
274 	if (pid)
275 		return thread_map__new_by_pid_str(pid);
276 
277 	if (!tid && uid != UINT_MAX)
278 		return thread_map__new_by_uid(uid);
279 
280 	return thread_map__new_by_tid_str(tid);
281 }
282 
thread_map__delete(struct thread_map * threads)283 void thread_map__delete(struct thread_map *threads)
284 {
285 	free(threads);
286 }
287 
thread_map__fprintf(struct thread_map * threads,FILE * fp)288 size_t thread_map__fprintf(struct thread_map *threads, FILE *fp)
289 {
290 	int i;
291 	size_t printed = fprintf(fp, "%d thread%s: ",
292 				 threads->nr, threads->nr > 1 ? "s" : "");
293 	for (i = 0; i < threads->nr; ++i)
294 		printed += fprintf(fp, "%s%d", i ? ", " : "", threads->map[i]);
295 
296 	return printed + fprintf(fp, "\n");
297 }
298