2 * pstree.c - display process tree
4 * Copyright (C) 1993-2002 Werner Almesberger
5 * Copyright (C) 2002-2009 Craig Small
6 * Copyright (C) 2010 Lauri Kasanen
8 * Based on pstree (PSmisc) 22.13.
10 * Licensed under GPLv2, see file LICENSE in this source tree.
13 //config:config PSTREE
14 //config: bool "pstree"
17 //config: Display a tree of processes.
19 //applet:IF_PSTREE(APPLET(pstree, BB_DIR_USR_BIN, BB_SUID_DROP))
21 //kbuild:lib-$(CONFIG_PSTREE) += pstree.o
23 //usage:#define pstree_trivial_usage
24 //usage: "[-p] [PID|USER]"
25 //usage:#define pstree_full_usage "\n\n"
26 //usage: "Display process tree, optionally start from USER or PID\n"
27 //usage: "\n -p Show pids"
31 #define PROC_BASE "/proc"
33 #define OPT_PID (1 << 0)
38 char comm[COMM_LEN + 1];
39 // char flags; - unused, delete?
42 struct child *children;
48 //#define PFLAG_THREAD 0x01
50 typedef struct child {
59 #define single_3 "---"
63 /* 0-based. IOW: the number of chars we printed on current line */
65 unsigned output_width;
67 /* The buffers will be dynamically increased in size as needed */
74 smallint dumped; /* used by dump_by_user */
76 #define G (*ptr_to_globals)
77 #define INIT_G() do { \
78 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
83 * Allocates additional buffer space for width and more as needed.
84 * The first call will allocate the first buffer.
86 * bufindex the index that will be used after the call to this function.
88 static void ensure_buffer_capacity(int bufindex)
90 if (bufindex >= G.capacity) {
92 G.width = xrealloc(G.width, G.capacity * sizeof(G.width[0]));
93 G.more = xrealloc(G.more, G.capacity * sizeof(G.more[0]));
97 /* NB: this function is never called with "bad" chars
98 * (control chars or chars >= 0x7f)
100 static void out_char(char c)
103 if (G.cur_x > G.output_width)
105 if (G.cur_x == G.output_width)
110 /* NB: this function is never called with "bad" chars
111 * (control chars or chars >= 0x7f)
113 static void out_string(const char *str)
119 static void out_newline(void)
125 static PROC *find_proc(pid_t pid)
129 for (walk = G.list; walk; walk = walk->next)
130 if (walk->pid == pid)
136 static PROC *new_proc(const char *comm, pid_t pid, uid_t uid)
138 PROC *new = xzalloc(sizeof(*new));
140 strcpy(new->comm, comm);
149 static void add_child(PROC *parent, PROC *child)
154 new = xmalloc(sizeof(*new));
157 for (walk = &parent->children; *walk; walk = &(*walk)->next) {
158 cmp = strcmp((*walk)->child->comm, child->comm);
161 if (cmp == 0 && (*walk)->child->uid > child->uid)
168 static void add_proc(const char *comm, pid_t pid, pid_t ppid,
169 uid_t uid /*, char isthread*/)
173 this = find_proc(pid);
175 this = new_proc(comm, pid, uid);
177 strcpy(this->comm, comm);
184 // this->flags |= PFLAG_THREAD;
186 parent = find_proc(ppid);
188 parent = new_proc("?", ppid, 0);
190 add_child(parent, this);
191 this->parent = parent;
194 static int tree_equal(const PROC *a, const PROC *b)
196 const CHILD *walk_a, *walk_b;
198 if (strcmp(a->comm, b->comm) != 0)
200 if ((option_mask32 /*& OPT_PID*/) && a->pid != b->pid)
203 for (walk_a = a->children, walk_b = b->children;
205 walk_a = walk_a->next, walk_b = walk_b->next
207 if (!tree_equal(walk_a->child, walk_b->child))
211 return !(walk_a || walk_b);
214 static int out_args(const char *mystr)
220 for (here = mystr; *here; here++) {
224 } else if (*here >= ' ' && *here < 0x7f) {
228 sprintf(tmpstr, "\\%03o", (unsigned char) *here);
238 dump_tree(PROC *current, int level, int rep, int leaf, int last, int closing)
240 CHILD *walk, *next, **scan;
241 int lvl, i, add, offset, count, comm_len, first;
242 char tmp[sizeof(int)*3 + 4];
248 for (lvl = 0; lvl < level; lvl++) {
249 i = G.width[lvl] + 1;
253 if (lvl == level - 1) {
257 out_string(branch_2);
260 if (G.more[lvl + 1]) {
271 add += sprintf(tmp, "%d*[", rep);
274 comm_len = out_args(current->comm);
275 if (option_mask32 /*& OPT_PID*/) {
276 comm_len += sprintf(tmp, "(%d)", (int)current->pid);
281 if (!current->children) {
286 ensure_buffer_capacity(level);
287 G.more[level] = !last;
289 G.width[level] = comm_len + G.cur_x - offset + add;
290 if (G.cur_x >= G.output_width) {
291 //out_string(first_3); - why? it won't print anything
298 for (walk = current->children; walk; walk = next) {
303 if (!tree_equal(walk->child, (*scan)->child))
304 scan = &(*scan)->next;
307 next = (*scan)->next;
309 *scan = (*scan)->next;
313 out_string(next ? first_3 : single_3);
317 dump_tree(walk->child, level + 1, count + 1,
318 walk == current->children, !next,
319 closing + (count ? 1 : 0));
323 static void dump_by_user(PROC *current, uid_t uid)
330 if (current->uid == uid) {
333 dump_tree(current, 0, 1, 1, 1, 0);
337 for (walk = current->children; walk; walk = walk->next)
338 dump_by_user(walk->child, uid);
341 #if ENABLE_FEATURE_SHOW_THREADS
342 static void handle_thread(const char *comm, pid_t pid, pid_t ppid, uid_t uid)
344 char threadname[COMM_LEN + 2];
345 sprintf(threadname, "{%.*s}", COMM_LEN - 2, comm);
346 add_proc(threadname, pid, ppid, uid/*, 1*/);
350 static void mread_proc(void)
352 procps_status_t *p = NULL;
354 int flags = PSSCAN_COMM | PSSCAN_PID | PSSCAN_PPID | PSSCAN_UIDGID | PSSCAN_TASKS;
356 while ((p = procps_scan(p, flags)) != NULL) {
357 #if ENABLE_FEATURE_SHOW_THREADS
358 if (p->pid != p->main_thread_pid)
359 handle_thread(p->comm, p->pid, parent, p->uid);
363 add_proc(p->comm, p->pid, p->ppid, p->uid/*, 0*/);
369 int pstree_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
370 int pstree_main(int argc UNUSED_PARAM, char **argv)
377 get_terminal_width_height(0, &G.output_width, NULL);
379 opt_complementary = "?1";
384 if (argv[0][0] >= '0' && argv[0][0] <= '9') {
385 pid = xatoi(argv[0]);
387 uid = xuname2uid(argv[0]);
394 dump_tree(find_proc(pid), 0, 1, 1, 1, 0);
396 dump_by_user(find_proc(1), uid);
398 bb_error_msg_and_die("no processes found");
402 if (ENABLE_FEATURE_CLEAN_UP) {