busybox/libbb/procps.c

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright 1998 by Albert Cahalan; all rights reserved.
 * Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"


typedef struct unsigned_to_name_map_t {
	unsigned id;
	char name[USERNAME_MAX_SIZE];
} unsigned_to_name_map_t;

typedef struct cache_t {
	unsigned_to_name_map_t *cache;
	int size;
} cache_t;

static cache_t username, groupname;

static void clear_cache(cache_t *cp)
{
	free(cp->cache);
	cp->cache = NULL;
	cp->size = 0;
}
void clear_username_cache(void)
{
	clear_cache(&username);
	clear_cache(&groupname);
}

#if 0 /* more generic, but we don't need that yet */
/* Returns -N-1 if not found. */
/* cp->cache[N] is allocated and must be filled in this case */
static int get_cached(cache_t *cp, unsigned id)
{
	int i;
	for (i = 0; i < cp->size; i++)
		if (cp->cache[i].id == id)
			return i;
	i = cp->size++;
	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
	cp->cache[i++].id = id;
	return -i;
}
#endif

typedef char* ug_func(char *name, long uid, int bufsize);
static char* get_cached(cache_t *cp, unsigned id, ug_func* fp)
{
	int i;
	for (i = 0; i < cp->size; i++)
		if (cp->cache[i].id == id)
			return cp->cache[i].name;
	i = cp->size++;
	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
	cp->cache[i].id = id;
	fp(cp->cache[i].name, id, sizeof(cp->cache[i].name));
	return cp->cache[i].name;
}
const char* get_cached_username(uid_t uid)
{
	return get_cached(&username, uid, bb_getpwuid);
}
const char* get_cached_groupname(gid_t gid)
{
	return get_cached(&groupname, gid, bb_getgrgid);
}


#define PROCPS_BUFSIZE 1024

static int read_to_buf(const char *filename, void *buf)
{
	ssize_t ret;
	ret = open_read_close(filename, buf, PROCPS_BUFSIZE-1);
	((char *)buf)[ret > 0 ? ret : 0] = '\0';
	return ret;
}

procps_status_t* alloc_procps_scan(int flags)
{
	procps_status_t* sp = xzalloc(sizeof(procps_status_t));
	sp->dir = xopendir("/proc");
	return sp;
}

void free_procps_scan(procps_status_t* sp)
{
	closedir(sp->dir);
	free(sp->cmd);
	free(sp);
}

void BUG_comm_size(void);
procps_status_t* procps_scan(procps_status_t* sp, int flags)
{
	struct dirent *entry;
	char buf[PROCPS_BUFSIZE];
	char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
	char *filename_tail;
	long tasknice;
	unsigned pid;
	int n;
	struct stat sb;

	if (!sp)
		sp = alloc_procps_scan(flags);

	for (;;) {
		entry = readdir(sp->dir);
		if (entry == NULL) {
			free_procps_scan(sp);
			return NULL;
		}
		pid = bb_strtou(entry->d_name, NULL, 10);
		if (errno)
			continue;

		/* After this point we have to break, not continue
		 * ("continue" would mean that current /proc/NNN
		 * is not a valid process info) */

		memset(&sp->rss, 0, sizeof(*sp) - offsetof(procps_status_t, rss));

		sp->pid = pid;
		if (!(flags & ~PSSCAN_PID)) break;

		filename_tail = filename + sprintf(filename, "/proc/%d", pid);

		if (flags & PSSCAN_UIDGID) {
			if (stat(filename, &sb))
				break;
			/* Need comment - is this effective or real UID/GID? */
			sp->uid = sb.st_uid;
			sp->gid = sb.st_gid;
		}

		if (flags & PSSCAN_STAT) {
			char *cp;
			/* see proc(5) for some details on this */
			strcpy(filename_tail, "/stat");
			n = read_to_buf(filename, buf);
			if (n < 0)
				break;
			cp = strrchr(buf, ')'); /* split into "PID (cmd" and "<rest>" */
			if (!cp || cp[1] != ' ')
				break;
			cp[0] = '\0';
			if (sizeof(sp->comm) < 16)
				BUG_comm_size();
			sscanf(buf, "%*s (%15c", sp->comm);
			n = sscanf(cp+2,
				"%c %u "               /* state, ppid */
				"%u %u %*s %*s "       /* pgid, sid, tty, tpgid */
				"%*s %*s %*s %*s %*s " /* flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
				"%lu %lu "             /* utime, stime */
				"%*s %*s %*s "         /* cutime, cstime, priority */
				"%ld "                 /* nice */
				"%*s %*s %*s "         /* timeout, it_real_value, start_time */
				"%*s "                 /* vsize */
				"%lu",                 /* rss */
				sp->state, &sp->ppid,
				&sp->pgid, &sp->sid,
				&sp->utime, &sp->stime,
				&tasknice,
				&sp->rss);
			if (n != 8)
				break;

			if (sp->rss == 0 && sp->state[0] != 'Z')
				sp->state[1] = 'W';
			else
				sp->state[1] = ' ';
			if (tasknice < 0)
				sp->state[2] = '<';
			else if (tasknice > 0)
				sp->state[2] = 'N';
			else
				sp->state[2] = ' ';

#ifdef PAGE_SHIFT
			sp->rss <<= (PAGE_SHIFT - 10);     /* 2**10 = 1kb */
#else
			sp->rss *= (getpagesize() >> 10);     /* 2**10 = 1kb */
#endif
		}

		if (flags & PSSCAN_CMD) {
			free(sp->cmd);
			sp->cmd = NULL;
			strcpy(filename_tail, "/cmdline");
			n = read_to_buf(filename, buf);
			if (n <= 0)
				break;
			if (buf[n-1] == '\n') {
				if (!--n)
					break;
				buf[n] = '\0';
			}
			do {
				n--;
				if ((unsigned char)(buf[n]) < ' ')
					buf[n] = ' ';
			} while (n);
			sp->cmd = xstrdup(buf);
		}
		break;
	}
	return sp;
}
/* from kernel:
	//             pid comm S ppid pgid sid tty_nr tty_pgrp flg
	sprintf(buffer,"%d (%s) %c %d  %d   %d  %d     %d       %lu %lu \
%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
%lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu %llu\n",
		task->pid,
		tcomm,
		state,
		ppid,
		pgid,
		sid,
		tty_nr,
		tty_pgrp,
		task->flags,
		min_flt,

		cmin_flt,
		maj_flt,
		cmaj_flt,
		cputime_to_clock_t(utime),
		cputime_to_clock_t(stime),
		cputime_to_clock_t(cutime),
		cputime_to_clock_t(cstime),
		priority,
		nice,
		num_threads,
		// 0,
		start_time,
		vsize,
		mm ? get_mm_rss(mm) : 0,
		rsslim,
		mm ? mm->start_code : 0,
		mm ? mm->end_code : 0,
		mm ? mm->start_stack : 0,
		esp,
		eip,
the rest is some obsolete cruft
*/
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Utility routines.
4	*
5	* Copyright 1998 by Albert Cahalan; all rights reserved.
6	* Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
7	*
8	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9	*/
10
11	#include "libbb.h"
12
13
14	typedef struct unsigned_to_name_map_t {
15	unsigned id;
16	char name[USERNAME_MAX_SIZE];
17	} unsigned_to_name_map_t;
18
19	typedef struct cache_t {
20	unsigned_to_name_map_t *cache;
21	int size;
22	} cache_t;
23
24	static cache_t username, groupname;
25
26	static void clear_cache(cache_t *cp)
27	{
28	free(cp->cache);
29	cp->cache = NULL;
30	cp->size = 0;
31	}
32	void clear_username_cache(void)
33	{
34	clear_cache(&username);
35	clear_cache(&groupname);
36	}
37
38	#if 0 /* more generic, but we don't need that yet */
39	/* Returns -N-1 if not found. */
40	/* cp->cache[N] is allocated and must be filled in this case */
41	static int get_cached(cache_t *cp, unsigned id)
42	{
43	int i;
44	for (i = 0; i < cp->size; i++)
45	if (cp->cache[i].id == id)
46	return i;
47	i = cp->size++;
48	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
49	cp->cache[i++].id = id;
50	return -i;
51	}
52	#endif
53
54	typedef char* ug_func(char *name, long uid, int bufsize);
55	static char* get_cached(cache_t cp, unsigned id, ug_func fp)
56	{
57	int i;
58	for (i = 0; i < cp->size; i++)
59	if (cp->cache[i].id == id)
60	return cp->cache[i].name;
61	i = cp->size++;
62	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
63	cp->cache[i].id = id;
64	fp(cp->cache[i].name, id, sizeof(cp->cache[i].name));
65	return cp->cache[i].name;
66	}
67	const char* get_cached_username(uid_t uid)
68	{
69	return get_cached(&username, uid, bb_getpwuid);
70	}
71	const char* get_cached_groupname(gid_t gid)
72	{
73	return get_cached(&groupname, gid, bb_getgrgid);
74	}
75
76
77	#define PROCPS_BUFSIZE 1024
78
79	static int read_to_buf(const char filename, void buf)
80	{
81	ssize_t ret;
82	ret = open_read_close(filename, buf, PROCPS_BUFSIZE-1);
83	((char *)buf)[ret > 0 ? ret : 0] = '\0';
84	return ret;
85	}
86
87	procps_status_t* alloc_procps_scan(int flags)
88	{
89	procps_status_t* sp = xzalloc(sizeof(procps_status_t));
90	sp->dir = xopendir("/proc");
91	return sp;
92	}
93
94	void free_procps_scan(procps_status_t* sp)
95	{
96	closedir(sp->dir);
97	free(sp->cmd);
98	free(sp);
99	}
100
101	void BUG_comm_size(void);
102	procps_status_t* procps_scan(procps_status_t* sp, int flags)
103	{
104	struct dirent *entry;
105	char buf[PROCPS_BUFSIZE];
106	char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
107	char *filename_tail;
108	long tasknice;
109	unsigned pid;
110	int n;
111	struct stat sb;
112
113	if (!sp)
114	sp = alloc_procps_scan(flags);
115
116	for (;;) {
117	entry = readdir(sp->dir);
118	if (entry == NULL) {
119	free_procps_scan(sp);
120	return NULL;
121	}
122	pid = bb_strtou(entry->d_name, NULL, 10);
123	if (errno)
124	continue;
125
126	/* After this point we have to break, not continue
127	* ("continue" would mean that current /proc/NNN
128	* is not a valid process info) */
129
130	memset(&sp->rss, 0, sizeof(*sp) - offsetof(procps_status_t, rss));
131
132	sp->pid = pid;
133	if (!(flags & ~PSSCAN_PID)) break;
134
135	filename_tail = filename + sprintf(filename, "/proc/%d", pid);
136
137	if (flags & PSSCAN_UIDGID) {
138	if (stat(filename, &sb))
139	break;
140	/* Need comment - is this effective or real UID/GID? */
141	sp->uid = sb.st_uid;
142	sp->gid = sb.st_gid;
143	}
144
145	if (flags & PSSCAN_STAT) {
146	char *cp;
147	/* see proc(5) for some details on this */
148	strcpy(filename_tail, "/stat");
149	n = read_to_buf(filename, buf);
150	if (n < 0)
151	break;
152	cp = strrchr(buf, ')'); /* split into "PID (cmd" and "<rest>" */
153	if (!cp \|\| cp[1] != ' ')
154	break;
155	cp[0] = '\0';
156	if (sizeof(sp->comm) < 16)
157	BUG_comm_size();
158	sscanf(buf, "%*s (%15c", sp->comm);
159	n = sscanf(cp+2,
160	"%c %u " /* state, ppid */
161	"%u %u %s %s " /* pgid, sid, tty, tpgid */
162	"%s %s %s %s %s " / flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
163	"%lu %lu " /* utime, stime */
164	"%s %s %s " / cutime, cstime, priority */
165	"%ld " /* nice */
166	"%s %s %s " / timeout, it_real_value, start_time */
167	"%s " / vsize */
168	"%lu", /* rss */
169	sp->state, &sp->ppid,
170	&sp->pgid, &sp->sid,
171	&sp->utime, &sp->stime,
172	&tasknice,
173	&sp->rss);
174	if (n != 8)
175	break;
176
177	if (sp->rss == 0 && sp->state[0] != 'Z')
178	sp->state[1] = 'W';
179	else
180	sp->state[1] = ' ';
181	if (tasknice < 0)
182	sp->state[2] = '<';
183	else if (tasknice > 0)
184	sp->state[2] = 'N';
185	else
186	sp->state[2] = ' ';
187
188	#ifdef PAGE_SHIFT
189	sp->rss <<= (PAGE_SHIFT - 10); /* 2*10 = 1kb /
190	#else
191	sp->rss = (getpagesize() >> 10); / 2*10 = 1kb /
192	#endif
193	}
194
195	if (flags & PSSCAN_CMD) {
196	free(sp->cmd);
197	sp->cmd = NULL;
198	strcpy(filename_tail, "/cmdline");
199	n = read_to_buf(filename, buf);
200	if (n <= 0)
201	break;
202	if (buf[n-1] == '\n') {
203	if (!--n)
204	break;
205	buf[n] = '\0';
206	}
207	do {
208	n--;
209	if ((unsigned char)(buf[n]) < ' ')
210	buf[n] = ' ';
211	} while (n);
212	sp->cmd = xstrdup(buf);
213	}
214	break;
215	}
216	return sp;
217	}
218	/* from kernel:
219	// pid comm S ppid pgid sid tty_nr tty_pgrp flg
220	sprintf(buffer,"%d (%s) %c %d %d %d %d %d %lu %lu \
221	%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
222	%lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu %llu\n",
223	task->pid,
224	tcomm,
225	state,
226	ppid,
227	pgid,
228	sid,
229	tty_nr,
230	tty_pgrp,
231	task->flags,
232	min_flt,
233
234	cmin_flt,
235	maj_flt,
236	cmaj_flt,
237	cputime_to_clock_t(utime),
238	cputime_to_clock_t(stime),
239	cputime_to_clock_t(cutime),
240	cputime_to_clock_t(cstime),
241	priority,
242	nice,
243	num_threads,
244	// 0,
245	start_time,
246	vsize,
247	mm ? get_mm_rss(mm) : 0,
248	rsslim,
249	mm ? mm->start_code : 0,
250	mm ? mm->end_code : 0,
251	mm ? mm->start_stack : 0,
252	esp,
253	eip,
254	the rest is some obsolete cruft
255	*/