[unix-history] / usr / src / usr.bin / gcore / gcore.c

/* Copyright (c) 1982 Regents of the University of California */

static char sccsid[] = "@(#)gcore.c	4.2	(Berkeley)	%G%";

/*
 * gcore - get core images of running processes
 *
 * Author: Eric Cooper
 * Written: Fall 1981.
 *
 * Inspired by a version 6 program by Len Levin, 1978.
 * Several pieces of code lifted from Bill Joy's 4BSD ps.
 *
 * Permission to copy or modify this program in whole or in part is hereby
 * granted, provided that the above credits are preserved.
 *
 * This code performs a simple simulation of the virtual memory system in user
 * code.  If the virtual memory system changes, this program must be modified
 * accordingly.  It must also be recompiled whenever system data structures
 * change.
 */
#include <stdio.h>
#include <nlist.h>
#include <sys/param.h>
#include <sys/dir.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <machine/pte.h>
#include <sys/vm.h>
#include <setjmp.h>

/* Various macros for efficiency. */

#define	min(a, b)	(a < b ? a : b)

#define	Seek(f, pos) {\
	if (lseek(f, (long) (pos), 0) != (long) (pos)) \
		panic("seek error"); \
}

#define	Read(f, addr, n) {\
	if (read(f, (char *) (addr), (int) (n)) != (int) (n)) \
		panic("read error"); \
}

#define	Get(f, pos, addr, n) {\
	Seek(f, pos); \
	Read(f, addr, n); \
}

struct	nlist nl[] = {
	{ "_proc" },
#define	X_PROC		0
	{ "_Usrptmap" },
#define	X_USRPTMA	1
	{ "_usrpt" },
#define	X_USRPT		2
	{ "_nswap" },
#define	X_NSWAP		3
	{ "_nproc" },
#define	X_NPROC		4
	{ 0 },
};

#define FEW	20		/* for fewer system calls */
struct	proc proc[FEW];

union {
	struct user user;
	char upages[UPAGES][NBPG];
} user;
#define u	user.user
#define uarea	user.upages

#define NLIST	"/vmunix"
#define KMEM	"/dev/kmem"
#define MEM	"/dev/mem"
#define SWAP	"/dev/drum"	/* "/dev/swap" on some systems */

int	nproc;
int	nswap;
struct	pte *Usrptmap, *usrpt;
char	coref[20];
int	kmem, mem, swap, cor;
jmp_buf	cont_frame;

main(argc, argv)
	int argc;
	char **argv;
{
	register int i, j;
	register struct proc *p;
	off_t procbase, procp;
	int pid, uid;
	char c;

	if (argc < 2) {
		printf("Usage: %s pid ...\n", argv[0]);
		exit(1);
	}
	openfiles();
	getkvars();
	procbase = getw(nl[X_PROC].n_value);
	nproc = getw(nl[X_NPROC].n_value);
	nswap = getw(nl[X_NSWAP].n_value);
	while (--argc > 0) {
		if ((pid = atoi(*++argv)) <= 0 || setjmp(cont_frame))
			continue;
		printf("%d: ", pid);
		procp = procbase;
		for (i = 0; i < nproc; i += FEW) {
			Seek(kmem, procp);
			j = nproc - i;
			if (j > FEW)
				j = FEW;
			j *= sizeof(struct proc);
			Read(kmem, (char *) proc, j);
			procp += j;
			for (j = j / sizeof(struct proc) - 1; j >= 0; j--) {
				p = &proc[j];
				if (p->p_pid == pid)
					goto found;
			}
		}
		printf("Process not found.\n");
		continue;
	found:
		if (p->p_uid != (uid = getuid()) && uid != 0) {
			printf("Not owner.\n");
			continue;
		}
		if (p->p_stat == SZOMB) {
			printf("Zombie.\n");
			continue;
		}
		if (p->p_flag & SWEXIT) {
			printf("Process exiting.\n");
			continue;
		}
		if (p->p_flag & SSYS) {
			printf("System process.\n");
			/* i.e. swapper or pagedaemon */
			continue;
		}
		sprintf(coref, "core.%d", pid);
		if ((cor = creat(coref, 0666)) < 0) {
			perror(coref);
			exit(1);
		}
		core(p);
		close(cor);
		printf("%s dumped\n", coref);
	}
}

getw(loc)
	off_t loc;
{
	int word;

	Get(kmem, loc, &word, sizeof(int));
	return (word);
}

openfiles()
{
	kmem = open(KMEM, 0);
	if (kmem < 0) {
		perror(KMEM);
		exit(1);
	}
	mem = open(MEM, 0);
	if (mem < 0) {
		perror(MEM);
		exit(1);
	}
	swap = open(SWAP, 0);
	if (swap < 0) {
		perror(SWAP);
		exit(1);
	}
}

getkvars()
{
	nlist(NLIST, nl);
	if (nl[0].n_type == 0) {
		printf("%s: No namelist\n", NLIST);
		exit(1);
	}
	Usrptmap = (struct pte *) nl[X_USRPTMA].n_value;
	usrpt = (struct pte *) nl[X_USRPT].n_value;
}

/*
 * Get the system page table entries (mapping the user page table).
 * These are the entries Usrptmap[i .. i + szpt],
 * where i = btokmx(p->p_p0br) and szpt = p->p_szpt.
 * For our purposes, we can skip over the ptes mapping
 * the text segment ptes.
 */
struct pte	*syspt;		/* pte's from Usrptmap */
int		nsysptes;

getsyspt(p)
	register struct proc *p;
{
	nsysptes = p->p_szpt - (p->p_tsize / NPTEPG);
	syspt = (struct pte *) malloc(nsysptes * sizeof(struct pte));
	if (syspt == NULL)
		panic("can't alloc %d page table entries", nsysptes);
	Get(kmem, &Usrptmap[btokmx(p->p_p0br) + (p->p_tsize / NPTEPG)],
		syspt, nsysptes * sizeof(struct pte));
}

/*
 * Get the user page table for a segment.
 * seg 0 = p0 (not including text)
 * seg 1 = p1 (stack and u area)
 * The system pt is consulted to find each page of user ptes.
 */
struct pte *
getpt(p, seg)
	register struct proc *p;
	int seg;
{
	register int i;
	register struct pte *spt;
	struct pte *pt;
	int nptes, offset, n;

	if (seg == 0) {
		nptes = p->p_dsize;
		spt = syspt;
		offset = p->p_tsize % NPTEPG;
	} else {
		nptes = p->p_ssize + UPAGES;
		spt = syspt + (nsysptes - ctopt(nptes));
		offset = -nptes % NPTEPG;
		if (offset < 0)
			offset += NPTEPG;
	}
	pt = (struct pte *) malloc(nptes * sizeof(struct pte));
	if (pt == NULL)
		panic("can't alloc %d page table entries", nptes);
	for (i = 0; i < nptes; i += n) {
		n = min(NPTEPG - offset, nptes - i);
		Get(mem, ctob(spt->pg_pfnum) + offset * sizeof(struct pte),
		     pt + i, n * sizeof(struct pte));
		spt++;
		offset = 0;
	}
	return (pt);
}

/*
 * Build the core file.
 */
core(p)
	register struct proc *p;
{
	register struct pte *p0, *p1;

	if (p->p_flag & SLOAD) {		/* page tables are resident */
		getsyspt(p);
		p0 = getpt(p, 0);
		p1 = getpt(p, 1);
#ifdef	DEBUG
		showpt(syspt, nsysptes, "system");
		showpt(p0, p->p_dsize, "p0");
		showpt(p1, p->p_ssize + UPAGES, "p1");
#endif
	}
	getu(p, &p1[p->p_ssize]);			/* u area */
	getseg(p, p->p_dsize, p0, &u.u_dmap, 0);	/* data */
	getseg(p, p->p_ssize, p1, &u.u_smap, 1);	/* stack */
	if (p->p_flag & SLOAD) {
		free((char *) syspt);
		free((char *) p0);
		free((char *) p1);
	}
}

/*
 * Get the u area.
 * Keeps around the u structure for later use
 * (the data and stack disk map structures).
 */
getu(p, pages)
	register struct proc *p;
	register struct pte *pages;
{
	register int i;

	if ((p->p_flag & SLOAD) == 0) {
		Get(swap, ctob(p->p_swaddr), uarea, ctob(UPAGES));
		write(cor, uarea, ctob(UPAGES));
		return;
	}
	for (i = 0; i < UPAGES; i += CLSIZE) {
		Get(mem, ctob(pages[i].pg_pfnum), uarea[i], ctob(CLSIZE));
		write(cor, uarea[i], ctob(CLSIZE));
	}
}

/*
 * Copy a segment to the core file.
 * The segment is described by its size in clicks,
 * its page table, its disk map, and whether or not
 * it grows backwards.
 * Note that the page table address is allowed to be meaningless
 * if the process is swapped out.
 */
getseg(p, segsize, pages, map, rev)
	register struct proc *p;
	int segsize;
	register struct pte *pages;
	struct dmap *map;
{
	register int i;
	struct dblock db;
	int size;
	char buf[ctob(CLSIZE)];

	for (i = 0; i < segsize; i += CLSIZE) {
		size = min(CLSIZE, segsize - i);
		if ((p->p_flag & SLOAD) == 0 || pages[i].pg_fod ||
		    pages[i].pg_pfnum == 0) {
			vstodb(i, size, map, &db, rev);
			Get(swap, ctob(db.db_base), buf, ctob(size));
			write(cor, buf, ctob(size));
		} else {
			Get(mem, ctob(pages[i].pg_pfnum), buf, ctob(size));
			write(cor, buf, ctob(size));
		}
	}
}

/*
 * Given a base/size pair in virtual swap area,
 * return a physical base/size pair which is the
 * (largest) initial, physically contiguous block.
 */
vstodb(vsbase, vssize, dmp, dbp, rev)
	register int vsbase;
	int vssize;
	struct dmap *dmp;
	register struct dblock *dbp;
{
	register int blk = DMMIN;
	register swblk_t *ip = dmp->dm_map;

	if (vsbase < 0 || vsbase + vssize > dmp->dm_size)
		panic("can't make sense out of virtual memory (gcore probably needs to be recompiled)");
	while (vsbase >= blk) {
		vsbase -= blk;
		if (blk < DMMAX)
			blk *= 2;
		ip++;
	}
	if (*ip <= 0 || *ip + blk > nswap)
		panic("vstodb *ip");
	dbp->db_size = MIN(vssize, blk - vsbase);
	dbp->db_base = *ip + (rev ? blk - (vsbase + dbp->db_size) : vsbase);
}

/*VARARGS1*/
panic(cp, a, b, c, d)
	char *cp;
{
	printf(cp, a, b, c, d);
	printf("\n");
	longjmp(cont_frame, 1);
}

/* 
 * Debugging routine to print out page table.
 */
#ifdef	DEBUG
showpt(pt, n, s)
	struct pte *pt;
	int n;
	char *s;
{
	register struct pte *p;
	register int i;

	printf("*** %s page table\n", s);
	for (i = 0, p = pt; i < n; i++, p++)
		if (! p->pg_fod)
			printf("%d: %x\n", i, p->pg_pfnum);
}
#endif
Commit	Line	Data
4f626618 KM	1	/* Copyright (c) 1982 Regents of the University of California */
4f626618 KM	2
57ee57ff	3	static char sccsid[] = "@(#)gcore.c 4.2 (Berkeley) %G%";
4f626618 KM	4
	5	/*
	6	* gcore - get core images of running processes
	7	*
	8	* Author: Eric Cooper
	9	* Written: Fall 1981.
	10	*
	11	* Inspired by a version 6 program by Len Levin, 1978.
	12	* Several pieces of code lifted from Bill Joy's 4BSD ps.
	13	*
	14	* Permission to copy or modify this program in whole or in part is hereby
	15	* granted, provided that the above credits are preserved.
	16	*
	17	* This code performs a simple simulation of the virtual memory system in user
	18	* code. If the virtual memory system changes, this program must be modified
	19	* accordingly. It must also be recompiled whenever system data structures
	20	* change.
	21	*/
	22	#include <stdio.h>
	23	#include <nlist.h>
	24	#include <sys/param.h>
	25	#include <sys/dir.h>
	26	#include <sys/user.h>
	27	#include <sys/proc.h>
57ee57ff	28	#include <machine/pte.h>
4f626618 KM	29	#include <sys/vm.h>
	30	#include <setjmp.h>
	31
	32	/* Various macros for efficiency. */
	33
	34	#define min(a, b) (a < b ? a : b)
	35
	36	#define Seek(f, pos) {\
	37	if (lseek(f, (long) (pos), 0) != (long) (pos)) \
	38	panic("seek error"); \
	39	}
	40
	41	#define Read(f, addr, n) {\
	42	if (read(f, (char *) (addr), (int) (n)) != (int) (n)) \
	43	panic("read error"); \
	44	}
	45
	46	#define Get(f, pos, addr, n) {\
	47	Seek(f, pos); \
	48	Read(f, addr, n); \
	49	}
	50
	51	struct nlist nl[] = {
	52	{ "_proc" },
	53	#define X_PROC 0
	54	{ "_Usrptmap" },
	55	#define X_USRPTMA 1
	56	{ "_usrpt" },
	57	#define X_USRPT 2
	58	{ "_nswap" },
	59	#define X_NSWAP 3
	60	{ "_nproc" },
	61	#define X_NPROC 4
	62	{ 0 },
	63	};
	64
	65	#define FEW 20 /* for fewer system calls */
	66	struct proc proc[FEW];
	67
	68	union {
	69	struct user user;
	70	char upages[UPAGES][NBPG];
	71	} user;
	72	#define u user.user
	73	#define uarea user.upages
	74
	75	#define NLIST "/vmunix"
	76	#define KMEM "/dev/kmem"
	77	#define MEM "/dev/mem"
	78	#define SWAP "/dev/drum" /* "/dev/swap" on some systems */
	79
	80	int nproc;
	81	int nswap;
	82	struct pte Usrptmap, usrpt;
	83	char coref[20];
	84	int kmem, mem, swap, cor;
	85	jmp_buf cont_frame;
	86
	87	main(argc, argv)
	88	int argc;
	89	char **argv;
	90	{
	91	register int i, j;
	92	register struct proc *p;
93	off_t procbase, procp;
94	int pid, uid;
95	char c;
96
97	if (argc < 2) {
98	printf("Usage: %s pid ...\n", argv[0]);
99	exit(1);
100	}
101	openfiles();
102	getkvars();
103	procbase = getw(nl[X_PROC].n_value);
104	nproc = getw(nl[X_NPROC].n_value);
105	nswap = getw(nl[X_NSWAP].n_value);
106	while (--argc > 0) {
107	if ((pid = atoi(*++argv)) <= 0 \|\| setjmp(cont_frame))
108	continue;
109	printf("%d: ", pid);
110	procp = procbase;
111	for (i = 0; i < nproc; i += FEW) {
112	Seek(kmem, procp);
113	j = nproc - i;
114	if (j > FEW)
115	j = FEW;
116	j *= sizeof(struct proc);
117	Read(kmem, (char *) proc, j);
118	procp += j;
119	for (j = j / sizeof(struct proc) - 1; j >= 0; j--) {
120	p = &proc[j];
121	if (p->p_pid == pid)
122	goto found;
123	}
124	}
125	printf("Process not found.\n");
126	continue;
127	found:
128	if (p->p_uid != (uid = getuid()) && uid != 0) {
129	printf("Not owner.\n");
130	continue;
131	}
132	if (p->p_stat == SZOMB) {
133	printf("Zombie.\n");
134	continue;
135	}
136	if (p->p_flag & SWEXIT) {
137	printf("Process exiting.\n");
138	continue;
139	}
140	if (p->p_flag & SSYS) {
141	printf("System process.\n");
142	/* i.e. swapper or pagedaemon */
143	continue;
144	}
145	sprintf(coref, "core.%d", pid);
146	if ((cor = creat(coref, 0666)) < 0) {
147	perror(coref);
148	exit(1);
149	}
150	core(p);
151	close(cor);
152	printf("%s dumped\n", coref);
153	}
154	}
155
156	getw(loc)
157	off_t loc;
158	{
159	int word;
160
161	Get(kmem, loc, &word, sizeof(int));
162	return (word);
163	}
164
165	openfiles()
166	{
167	kmem = open(KMEM, 0);
168	if (kmem < 0) {
169	perror(KMEM);
170	exit(1);
171	}
172	mem = open(MEM, 0);
173	if (mem < 0) {
174	perror(MEM);
175	exit(1);
176	}
177	swap = open(SWAP, 0);
178	if (swap < 0) {
179	perror(SWAP);
180	exit(1);
181	}
182	}
183
184	getkvars()
185	{
186	nlist(NLIST, nl);
187	if (nl[0].n_type == 0) {
188	printf("%s: No namelist\n", NLIST);
189	exit(1);
190	}
191	Usrptmap = (struct pte *) nl[X_USRPTMA].n_value;
192	usrpt = (struct pte *) nl[X_USRPT].n_value;
193	}
194
195	/*
196	* Get the system page table entries (mapping the user page table).
197	* These are the entries Usrptmap[i .. i + szpt],
198	* where i = btokmx(p->p_p0br) and szpt = p->p_szpt.
199	* For our purposes, we can skip over the ptes mapping
200	* the text segment ptes.
201	*/
202	struct pte syspt; / pte's from Usrptmap */
203	int nsysptes;
204
205	getsyspt(p)
206	register struct proc *p;
207	{
208	nsysptes = p->p_szpt - (p->p_tsize / NPTEPG);
209	syspt = (struct pte ) malloc(nsysptes sizeof(struct pte));
210	if (syspt == NULL)
211	panic("can't alloc %d page table entries", nsysptes);
212	Get(kmem, &Usrptmap[btokmx(p->p_p0br) + (p->p_tsize / NPTEPG)],
213	syspt, nsysptes * sizeof(struct pte));
214	}
215
216	/*
217	* Get the user page table for a segment.
218	* seg 0 = p0 (not including text)
219	* seg 1 = p1 (stack and u area)
220	* The system pt is consulted to find each page of user ptes.
221	*/
222	struct pte *
223	getpt(p, seg)
224	register struct proc *p;
225	int seg;
226	{
227	register int i;
228	register struct pte *spt;
229	struct pte *pt;
230	int nptes, offset, n;
231
232	if (seg == 0) {
233	nptes = p->p_dsize;
234	spt = syspt;
235	offset = p->p_tsize % NPTEPG;
236	} else {
237	nptes = p->p_ssize + UPAGES;
238	spt = syspt + (nsysptes - ctopt(nptes));
239	offset = -nptes % NPTEPG;
240	if (offset < 0)
241	offset += NPTEPG;
242	}
243	pt = (struct pte ) malloc(nptes sizeof(struct pte));
244	if (pt == NULL)
245	panic("can't alloc %d page table entries", nptes);
246	for (i = 0; i < nptes; i += n) {
247	n = min(NPTEPG - offset, nptes - i);
248	Get(mem, ctob(spt->pg_pfnum) + offset * sizeof(struct pte),
249	pt + i, n * sizeof(struct pte));
250	spt++;
251	offset = 0;
252	}
253	return (pt);
254	}
255
256	/*
257	* Build the core file.
258	*/
259	core(p)
260	register struct proc *p;
261	{
262	register struct pte p0, p1;
263
264	if (p->p_flag & SLOAD) { /* page tables are resident */
265	getsyspt(p);
266	p0 = getpt(p, 0);
267	p1 = getpt(p, 1);
268	#ifdef DEBUG
269	showpt(syspt, nsysptes, "system");
270	showpt(p0, p->p_dsize, "p0");
271	showpt(p1, p->p_ssize + UPAGES, "p1");
272	#endif
273	}
274	getu(p, &p1[p->p_ssize]); /* u area */
275	getseg(p, p->p_dsize, p0, &u.u_dmap, 0); /* data */
276	getseg(p, p->p_ssize, p1, &u.u_smap, 1); /* stack */
277	if (p->p_flag & SLOAD) {
278	free((char *) syspt);
279	free((char *) p0);
280	free((char *) p1);
281	}
282	}
283
284	/*
285	* Get the u area.
286	* Keeps around the u structure for later use
287	* (the data and stack disk map structures).
288	*/
289	getu(p, pages)
290	register struct proc *p;
291	register struct pte *pages;
292	{
293	register int i;
294
295	if ((p->p_flag & SLOAD) == 0) {
296	Get(swap, ctob(p->p_swaddr), uarea, ctob(UPAGES));
297	write(cor, uarea, ctob(UPAGES));
298	return;
299	}
300	for (i = 0; i < UPAGES; i += CLSIZE) {
301	Get(mem, ctob(pages[i].pg_pfnum), uarea[i], ctob(CLSIZE));
302	write(cor, uarea[i], ctob(CLSIZE));
303	}
304	}
305
306	/*
307	* Copy a segment to the core file.
308	* The segment is described by its size in clicks,
309	* its page table, its disk map, and whether or not
310	* it grows backwards.
311	* Note that the page table address is allowed to be meaningless
312	* if the process is swapped out.
313	*/
314	getseg(p, segsize, pages, map, rev)
315	register struct proc *p;
316	int segsize;
317	register struct pte *pages;
318	struct dmap *map;
319	{
320	register int i;
321	struct dblock db;
322	int size;
323	char buf[ctob(CLSIZE)];
324
325	for (i = 0; i < segsize; i += CLSIZE) {
326	size = min(CLSIZE, segsize - i);
327	if ((p->p_flag & SLOAD) == 0 \|\| pages[i].pg_fod \|\|
328	pages[i].pg_pfnum == 0) {
329	vstodb(i, size, map, &db, rev);
330	Get(swap, ctob(db.db_base), buf, ctob(size));
331	write(cor, buf, ctob(size));
332	} else {
333	Get(mem, ctob(pages[i].pg_pfnum), buf, ctob(size));
334	write(cor, buf, ctob(size));
335	}
336	}
337	}
338
339	/*
340	* Given a base/size pair in virtual swap area,
341	* return a physical base/size pair which is the
342	* (largest) initial, physically contiguous block.
343	*/
344	vstodb(vsbase, vssize, dmp, dbp, rev)
345	register int vsbase;
346	int vssize;
347	struct dmap *dmp;
348	register struct dblock *dbp;
349	{
350	register int blk = DMMIN;
351	register swblk_t *ip = dmp->dm_map;
352
353	if (vsbase < 0 \|\| vsbase + vssize > dmp->dm_size)
354	panic("can't make sense out of virtual memory (gcore probably needs to be recompiled)");
355	while (vsbase >= blk) {
356	vsbase -= blk;
357	if (blk < DMMAX)
358	blk *= 2;
359	ip++;
360	}
361	if (ip <= 0 \|\| ip + blk > nswap)
362	panic("vstodb *ip");
363	dbp->db_size = MIN(vssize, blk - vsbase);
364	dbp->db_base = *ip + (rev ? blk - (vsbase + dbp->db_size) : vsbase);
365	}
366
367	/VARARGS1/
368	panic(cp, a, b, c, d)
369	char *cp;
370	{
371	printf(cp, a, b, c, d);
372	printf("\n");
373	longjmp(cont_frame, 1);
374	}
375
376	/*
377	* Debugging routine to print out page table.
378	*/
379	#ifdef DEBUG
380	showpt(pt, n, s)
381	struct pte *pt;
382	int n;
383	char *s;
384	{
385	register struct pte *p;
386	register int i;
387
388	printf("*** %s page table\n", s);
389	for (i = 0, p = pt; i < n; i++, p++)
390	if (! p->pg_fod)
391	printf("%d: %x\n", i, p->pg_pfnum);
392	}
393	#endif