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 */
14static int filter(const struct dirent *dir)
15{
16	if (dir->d_name[0] == '.')
17		return 0;
18	else
19		return 1;
20}
21
22struct 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
49struct 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
61struct 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
126out_closedir:
127	closedir(proc);
128out:
129	return threads;
130
131out_free_threads:
132	free(threads);
133	return NULL;
134
135out_free_namelist:
136	for (i = 0; i < items; i++)
137		free(namelist[i]);
138	free(namelist);
139
140out_free_closedir:
141	free(threads);
142	threads = NULL;
143	goto out_closedir;
144}
145
146struct 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
157static 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_namelist;
192
193		threads = nt;
194
195		for (i = 0; i < items; i++) {
196			threads->map[j++] = atoi(namelist[i]->d_name);
197			free(namelist[i]);
198		}
199		threads->nr = total_tasks;
200		free(namelist);
201	}
202
203out:
204	strlist__delete(slist);
205	return threads;
206
207out_free_namelist:
208	for (i = 0; i < items; i++)
209		free(namelist[i]);
210	free(namelist);
211
212out_free_threads:
213	free(threads);
214	threads = NULL;
215	goto out;
216}
217
218static struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
219{
220	struct thread_map *threads = NULL, *nt;
221	int ntasks = 0;
222	pid_t tid, prev_tid = INT_MAX;
223	char *end_ptr;
224	struct str_node *pos;
225	struct strlist *slist;
226
227	/* perf-stat expects threads to be generated even if tid not given */
228	if (!tid_str) {
229		threads = malloc(sizeof(*threads) + sizeof(pid_t));
230		if (threads != NULL) {
231			threads->map[0] = -1;
232			threads->nr	= 1;
233		}
234		return threads;
235	}
236
237	slist = strlist__new(false, tid_str);
238	if (!slist)
239		return NULL;
240
241	strlist__for_each(pos, slist) {
242		tid = strtol(pos->s, &end_ptr, 10);
243
244		if (tid == INT_MIN || tid == INT_MAX ||
245		    (*end_ptr != '\0' && *end_ptr != ','))
246			goto out_free_threads;
247
248		if (tid == prev_tid)
249			continue;
250
251		ntasks++;
252		nt = realloc(threads, sizeof(*threads) + sizeof(pid_t) * ntasks);
253
254		if (nt == NULL)
255			goto out_free_threads;
256
257		threads = nt;
258		threads->map[ntasks - 1] = tid;
259		threads->nr		 = ntasks;
260	}
261out:
262	return threads;
263
264out_free_threads:
265	free(threads);
266	threads = NULL;
267	goto out;
268}
269
270struct thread_map *thread_map__new_str(const char *pid, const char *tid,
271				       uid_t uid)
272{
273	if (pid)
274		return thread_map__new_by_pid_str(pid);
275
276	if (!tid && uid != UINT_MAX)
277		return thread_map__new_by_uid(uid);
278
279	return thread_map__new_by_tid_str(tid);
280}
281
282void thread_map__delete(struct thread_map *threads)
283{
284	free(threads);
285}
286
287size_t thread_map__fprintf(struct thread_map *threads, FILE *fp)
288{
289	int i;
290	size_t printed = fprintf(fp, "%d thread%s: ",
291				 threads->nr, threads->nr > 1 ? "s" : "");
292	for (i = 0; i < threads->nr; ++i)
293		printed += fprintf(fp, "%s%d", i ? ", " : "", threads->map[i]);
294
295	return printed + fprintf(fp, "\n");
296}
297