path: root/procps/smemcap.c (plain)
blob: 7dc1601998b299b68dde6d120e49b3856a31bafc

1	/*
2	smemcap - a tool for meaningful memory reporting
3
4	Copyright 2008-2009 Matt Mackall <mpm@selenic.com>
5
6	This software may be used and distributed according to the terms of
7	the GNU General Public License version 2 or later, incorporated
8	herein by reference.
9	*/
10
11	//applet:IF_SMEMCAP(APPLET(smemcap, BB_DIR_USR_BIN, BB_SUID_DROP))
12
13	//kbuild:lib-$(CONFIG_SMEMCAP) += smemcap.o
14
15	//config:config SMEMCAP
16	//config: bool "smemcap"
17	//config: default y
18	//config: help
19	//config: smemcap is a tool for capturing process data for smem,
20	//config: a memory usage statistic tool.
21
22	#include "libbb.h"
23	#include "bb_archive.h"
24
25	struct fileblock {
26	struct fileblock *next;
27	char data[TAR_BLOCK_SIZE];
28	};
29
30	static void writeheader(const char *path, struct stat *sb, int type)
31	{
32	struct tar_header_t header;
33	int i, sum;
34
35	memset(&header, 0, TAR_BLOCK_SIZE);
36	strcpy(header.name, path);
37	sprintf(header.mode, "%o", sb->st_mode & 0777);
38	/* careful to not overflow fields! */
39	#ifdef BIONIC_L
40	sprintf(header.uid, "%uo", sb->st_uid & 07777777);
41	sprintf(header.gid, "%uo", sb->st_gid & 07777777);
42	#elif defined(__BIONIC__)
43	sprintf(header.uid, "%lo", sb->st_uid & 07777777);
44	sprintf(header.gid, "%lo", sb->st_gid & 07777777);
45	#else
46	sprintf(header.uid, "%o", sb->st_uid & 07777777);
47	sprintf(header.gid, "%o", sb->st_gid & 07777777);
48	#endif
49	sprintf(header.size, "%o", (unsigned)sb->st_size);
50	sprintf(header.mtime, "%llo", sb->st_mtime & 077777777777LL);
51	header.typeflag = type;
52	strcpy(header.magic, "ustar "); /* like GNU tar */
53
54	/* Calculate and store the checksum (the sum of all of the bytes of
55	* the header). The checksum field must be filled with blanks for the
56	* calculation. The checksum field is formatted differently from the
57	* other fields: it has 6 digits, a NUL, then a space -- rather than
58	* digits, followed by a NUL like the other fields... */
59	header.chksum[7] = ' ';
60	sum = ' ' * 7;
61	for (i = 0; i < TAR_BLOCK_SIZE; i++)
62	sum += ((unsigned char*)&header)[i];
63	sprintf(header.chksum, "%06o", sum);
64
65	xwrite(STDOUT_FILENO, &header, TAR_BLOCK_SIZE);
66	}
67
68	static void archivefile(const char *path)
69	{
70	struct fileblock *start, *cur;
71	struct fileblock **prev = &start;
72	int fd, r;
73	unsigned size = 0;
74	struct stat s;
75
76	/* buffer the file */
77	fd = xopen(path, O_RDONLY);
78	do {
79	cur = xzalloc(sizeof(*cur));
80	*prev = cur;
81	prev = &cur->next;
82	r = full_read(fd, cur->data, TAR_BLOCK_SIZE);
83	if (r > 0)
84	size += r;
85	} while (r == TAR_BLOCK_SIZE);
86
87	/* write archive header */
88	fstat(fd, &s);
89	close(fd);
90	s.st_size = size;
91	writeheader(path, &s, '0');
92
93	/* dump file contents */
94	for (cur = start; (int)size > 0; size -= TAR_BLOCK_SIZE) {
95	xwrite(STDOUT_FILENO, cur->data, TAR_BLOCK_SIZE);
96	start = cur;
97	cur = cur->next;
98	free(start);
99	}
100	}
101
102	static void archivejoin(const char *sub, const char *name)
103	{
104	char path[sizeof(long long)*3 + sizeof("/cmdline")];
105	sprintf(path, "%s/%s", sub, name);
106	archivefile(path);
107	}
108
109	//usage:#define smemcap_trivial_usage ">SMEMDATA.TAR"
110	//usage:#define smemcap_full_usage "\n\n"
111	//usage: "Collect memory usage data in /proc and write it to stdout"
112
113	int smemcap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
114	int smemcap_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
115	{
116	DIR *d;
117	struct dirent *de;
118
119	xchdir("/proc");
120	d = xopendir(".");
121
122	archivefile("meminfo");
123	archivefile("version");
124	while ((de = readdir(d)) != NULL) {
125	if (isdigit(de->d_name[0])) {
126	struct stat s;
127	memset(&s, 0, sizeof(s));
128	s.st_mode = 0555;
129	writeheader(de->d_name, &s, '5');
130	archivejoin(de->d_name, "smaps");
131	archivejoin(de->d_name, "cmdline");
132	archivejoin(de->d_name, "stat");
133	}
134	}
135
136	if (ENABLE_FEATURE_CLEAN_UP)
137	closedir(d);
138
139	return EXIT_SUCCESS;
140	}
141