xref: /illumos-gate/usr/src/cmd/prstat/prfile.c (revision bb9b6b3f59b8820022416cea99b49c50fef6e391)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1999 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/stat.h>
30 #include <fcntl.h>
31 #include <unistd.h>
32 #include <stdlib.h>
33 #include <errno.h>
34 #include <string.h>
35 #include <strings.h>
36 
37 #include "prtable.h"
38 #include "prutil.h"
39 #include "prfile.h"
40 
41 #define	FDS_TABLE_SIZE	1024
42 
43 static fd_t *fd_tbl = NULL;
44 static int fd_max;
45 static int fd_cnt;
46 static int fd_cnt_cur;
47 static int fd_cnt_old;
48 static fds_t *fds_tbl[FDS_TABLE_SIZE];
49 
50 void
51 fd_init(int n)
52 {
53 	fd_max = n;
54 	fd_cnt = fd_cnt_cur = fd_cnt_old = 0;
55 	fd_tbl = Zalloc(sizeof (fd_t) * n);
56 	(void) memset(fds_tbl, 0, sizeof (fds_t *) * FDS_TABLE_SIZE);
57 }
58 
59 void
60 fd_exit()
61 {
62 	if (fd_tbl)
63 		free(fd_tbl);
64 }
65 
66 void
67 fd_close(fd_t *fdp)
68 {
69 	if (fdp) {
70 		if (fdp->fd_fd >= 0 && fdp->fd_name[0] != '\0') {
71 			(void) close(fdp->fd_fd);
72 			fd_cnt--;
73 		}
74 
75 		(void) memset(fdp, 0, sizeof (fd_t));
76 		fdp->fd_fd = -1;
77 	}
78 }
79 
80 void
81 fd_closeall()
82 {
83 	fd_t *fdp = fd_tbl;
84 	int i;
85 
86 	for (i = 0; i < fd_max; i++) {
87 		fd_close(fdp);
88 		fdp++;
89 	}
90 }
91 
92 static void
93 fd_recycle()
94 {
95 	fd_t *fdp = fd_tbl;
96 	int counter;
97 	int i;
98 
99 	counter = abs(fd_cnt_old - fd_cnt) + NUM_RESERVED_FD;
100 
101 	for (i = 0; i < fd_max; i++, fdp++) {
102 
103 		if (fdp->fd_fd == -1)
104 			continue;	/* skip recycled ones */
105 
106 		if (fdp->fd_name[0] != '\0') {	/* file has name */
107 			(void) close(fdp->fd_fd);
108 			fd_cnt--;
109 			counter--;
110 			fdp->fd_fd = -1;
111 		}
112 
113 		if (counter == 0)
114 			break;
115 	}
116 }
117 
118 fd_t *
119 fd_open(char *name, int flags, fd_t *fdp)
120 {
121 	fd_t *fdp_new;
122 	int fd;
123 
124 	if (fd_cnt > fd_max - NUM_RESERVED_FD)
125 		fd_recycle();
126 
127 	if (fdp != NULL) {
128 		if ((strcmp(fdp->fd_name, name) == 0) && (fdp->fd_fd >= 0)) {
129 			fd_cnt_cur++;
130 			return (fdp);
131 		}
132 	}
133 
134 again:	fd = open(name, flags);
135 
136 	if (fd == -1) {
137 		if ((errno == EMFILE) || (errno == ENFILE)) {
138 			fd_recycle();
139 			goto again;
140 		}
141 		fdp_new = NULL;
142 	} else {
143 		fdp_new = &fd_tbl[fd];
144 		fdp_new->fd_fd = fd;
145 		fdp_new->fd_flags = flags;
146 		(void) strcpy(fdp_new->fd_name, name);
147 		fd_cnt++;
148 		fd_cnt_cur++;
149 	}
150 	return (fdp_new);
151 }
152 
153 int
154 fd_getfd(fd_t *fdp)
155 {
156 	return (fdp->fd_fd);
157 }
158 
159 void
160 fd_update()
161 {
162 	fd_cnt_old = fd_cnt_cur;
163 	fd_cnt_cur = 0;
164 }
165 
166 fds_t *
167 fds_get(pid_t pid)
168 {
169 	fds_t *fdsp;
170 	int hash = pid % FDS_TABLE_SIZE;
171 
172 	for (fdsp = fds_tbl[hash]; fdsp; fdsp = fdsp->fds_next)
173 		if (fdsp->fds_pid == pid)	/* searching for pid */
174 			return (fdsp);
175 
176 	fdsp = Zalloc(sizeof (fds_t));	/* adding new if pid was not found */
177 	fdsp->fds_pid = pid;
178 	fdsp->fds_next = fds_tbl[hash];
179 	fds_tbl[hash] = fdsp;
180 	return (fdsp);
181 }
182 
183 void
184 fds_rm(pid_t pid)
185 {
186 	fds_t *fds;
187 	fds_t *fds_prev = NULL;
188 	int hash = pid % FDS_TABLE_SIZE;
189 
190 	for (fds = fds_tbl[hash]; fds && fds->fds_pid != pid;
191 	    fds = fds->fds_next)	/* finding pid */
192 		fds_prev = fds;
193 
194 	if (fds) {			/* if pid was found */
195 
196 		fd_close(fds->fds_psinfo);
197 		fd_close(fds->fds_usage);
198 		fd_close(fds->fds_lpsinfo);
199 		fd_close(fds->fds_lusage);
200 
201 		if (fds_prev)
202 			fds_prev->fds_next = fds->fds_next;
203 		else
204 			fds_tbl[hash] = fds->fds_next;
205 
206 		free(fds);
207 	}
208 }
209