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-rw-r--r--arch/um/os-Linux/Makefile4
-rw-r--r--arch/um/os-Linux/umid.c292
2 files changed, 294 insertions, 2 deletions
diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
index b83ac8e21c35..11e30b13e318 100644
--- a/arch/um/os-Linux/Makefile
+++ b/arch/um/os-Linux/Makefile
@@ -4,11 +4,11 @@
4# 4#
5 5
6obj-y = aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \ 6obj-y = aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \
7 start_up.o time.o tt.o tty.o uaccess.o user_syms.o drivers/ \ 7 start_up.o time.o tt.o tty.o uaccess.o umid.o user_syms.o drivers/ \
8 sys-$(SUBARCH)/ 8 sys-$(SUBARCH)/
9 9
10USER_OBJS := aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \ 10USER_OBJS := aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \
11 start_up.o time.o tt.o tty.o uaccess.o 11 start_up.o time.o tt.o tty.o uaccess.o umid.o
12 12
13elf_aux.o: $(ARCH_DIR)/kernel-offsets.h 13elf_aux.o: $(ARCH_DIR)/kernel-offsets.h
14CFLAGS_elf_aux.o += -I$(objtree)/arch/um 14CFLAGS_elf_aux.o += -I$(objtree)/arch/um
diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c
new file mode 100644
index 000000000000..77d69a348cf4
--- /dev/null
+++ b/arch/um/os-Linux/umid.c
@@ -0,0 +1,292 @@
1#include <stdio.h>
2#include <unistd.h>
3#include <stdlib.h>
4#include <string.h>
5#include <errno.h>
6#include <signal.h>
7#include <dirent.h>
8#include <sys/stat.h>
9#include <sys/param.h>
10#include "init.h"
11#include "os.h"
12#include "user.h"
13#include "mode.h"
14
15#define UML_DIR "~/.uml/"
16
17#define UMID_LEN 64
18
19/* Changed by set_umid, which is run early in boot */
20char umid[UMID_LEN] = { 0 };
21
22/* Changed by set_uml_dir and make_uml_dir, which are run early in boot */
23static char *uml_dir = UML_DIR;
24
25static int __init make_uml_dir(void)
26{
27 char dir[512] = { '\0' };
28 int len;
29
30 if(*uml_dir == '~'){
31 char *home = getenv("HOME");
32
33 if(home == NULL){
34 printf("make_uml_dir : no value in environment for "
35 "$HOME\n");
36 exit(1);
37 }
38 strlcpy(dir, home, sizeof(dir));
39 uml_dir++;
40 }
41 strlcat(dir, uml_dir, sizeof(dir));
42 len = strlen(dir);
43 if (len > 0 && dir[len - 1] != '/')
44 strlcat(dir, "/", sizeof(dir));
45
46 uml_dir = malloc(strlen(dir) + 1);
47 if (uml_dir == NULL) {
48 printf("make_uml_dir : malloc failed, errno = %d\n", errno);
49 exit(1);
50 }
51 strcpy(uml_dir, dir);
52
53 if((mkdir(uml_dir, 0777) < 0) && (errno != EEXIST)){
54 printf("Failed to mkdir '%s': %s\n", uml_dir, strerror(errno));
55 return(-1);
56 }
57 return 0;
58}
59
60static int actually_do_remove(char *dir)
61{
62 DIR *directory;
63 struct dirent *ent;
64 int len;
65 char file[256];
66
67 directory = opendir(dir);
68 if(directory == NULL){
69 printk("actually_do_remove : couldn't open directory '%s', "
70 "errno = %d\n", dir, errno);
71 return(1);
72 }
73 while((ent = readdir(directory)) != NULL){
74 if(!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))
75 continue;
76 len = strlen(dir) + sizeof("/") + strlen(ent->d_name) + 1;
77 if(len > sizeof(file)){
78 printk("Not deleting '%s' from '%s' - name too long\n",
79 ent->d_name, dir);
80 continue;
81 }
82 sprintf(file, "%s/%s", dir, ent->d_name);
83 if(unlink(file) < 0){
84 printk("actually_do_remove : couldn't remove '%s' "
85 "from '%s', errno = %d\n", ent->d_name, dir,
86 errno);
87 return(1);
88 }
89 }
90 if(rmdir(dir) < 0){
91 printk("actually_do_remove : couldn't rmdir '%s', "
92 "errno = %d\n", dir, errno);
93 return(1);
94 }
95 return(0);
96}
97
98extern int tracing_pid;
99
100static int not_dead_yet(char *dir)
101{
102 char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")];
103 char pid[sizeof("nnnnn\0")], *end;
104 int dead, fd, p, n;
105
106 sprintf(file, "%s/pid", dir);
107 dead = 0;
108 fd = os_open_file(file, of_read(OPENFLAGS()), 0);
109 if(fd < 0){
110 if(fd != -ENOENT){
111 printk("not_dead_yet : couldn't open pid file '%s', "
112 "err = %d\n", file, -fd);
113 return(1);
114 }
115 dead = 1;
116 }
117 if(fd > 0){
118 n = os_read_file(fd, pid, sizeof(pid));
119 if(n < 0){
120 printk("not_dead_yet : couldn't read pid file '%s', "
121 "err = %d\n", file, -n);
122 return(1);
123 }
124 p = strtoul(pid, &end, 0);
125 if(end == pid){
126 printk("not_dead_yet : couldn't parse pid file '%s', "
127 "errno = %d\n", file, errno);
128 dead = 1;
129 }
130 if(((kill(p, 0) < 0) && (errno == ESRCH)) ||
131 (p == CHOOSE_MODE(tracing_pid, os_getpid())))
132 dead = 1;
133 }
134 if(!dead)
135 return(1);
136 return(actually_do_remove(dir));
137}
138
139static void __init create_pid_file(void)
140{
141 char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")];
142 char pid[sizeof("nnnnn\0")];
143 int fd, n;
144
145 if(umid_file_name("pid", file, sizeof(file)))
146 return;
147
148 fd = os_open_file(file, of_create(of_excl(of_rdwr(OPENFLAGS()))),
149 0644);
150 if(fd < 0){
151 printf("Open of machine pid file \"%s\" failed: %s\n",
152 file, strerror(-fd));
153 return;
154 }
155
156 sprintf(pid, "%d\n", os_getpid());
157 n = os_write_file(fd, pid, strlen(pid));
158 if(n != strlen(pid))
159 printf("Write of pid file failed - err = %d\n", -n);
160 os_close_file(fd);
161}
162
163int __init set_umid(char *name, int (*printer)(const char *fmt, ...))
164{
165 if(strlen(name) > UMID_LEN - 1)
166 (*printer)("Unique machine name is being truncated to %d "
167 "characters\n", UMID_LEN);
168 strlcpy(umid, name, sizeof(umid));
169
170 return 0;
171}
172
173static int umid_setup = 0;
174
175int __init make_umid(int (*printer)(const char *fmt, ...))
176{
177 int fd, err;
178 char tmp[256];
179
180 make_uml_dir();
181
182 if(*umid == '\0'){
183 strlcpy(tmp, uml_dir, sizeof(tmp));
184 strcat(tmp, "XXXXXX");
185 fd = mkstemp(tmp);
186 if(fd < 0){
187 (*printer)("make_umid - mkstemp(%s) failed: %s\n",
188 tmp,strerror(errno));
189 return(1);
190 }
191
192 os_close_file(fd);
193 /* There's a nice tiny little race between this unlink and
194 * the mkdir below. It'd be nice if there were a mkstemp
195 * for directories.
196 */
197 unlink(tmp);
198 set_umid(&tmp[strlen(uml_dir)], printer);
199 }
200
201 sprintf(tmp, "%s%s", uml_dir, umid);
202 err = mkdir(tmp, 0777);
203 if(err < 0){
204 if(errno == EEXIST){
205 if(not_dead_yet(tmp))
206 return -EEXIST;
207 err = mkdir(tmp, 0777);
208 }
209 }
210 if(err < 0){
211 (*printer)("Failed to create %s - errno = %d\n", umid, errno);
212 return(-1);
213 }
214
215 umid_setup = 1;
216
217 create_pid_file();
218
219 return 0;
220}
221
222static int __init make_umid_init(void)
223{
224 make_umid(printk);
225
226 return(0);
227}
228
229__initcall(make_umid_init);
230
231int __init umid_file_name(char *name, char *buf, int len)
232{
233 int n, err;
234
235 if(!umid_setup){
236 err = make_umid(printk);
237 if(err)
238 return err;
239 }
240
241 n = strlen(uml_dir) + strlen(umid) + strlen("/") + strlen(name) + 1;
242 if(n > len){
243 printk("umid_file_name : buffer too short\n");
244 return(-1);
245 }
246
247 sprintf(buf, "%s%s/%s", uml_dir, umid, name);
248 return(0);
249}
250
251extern int umid_is_random;
252
253char *get_umid(int only_if_set)
254{
255 if(only_if_set && umid_is_random)
256 return NULL;
257 return umid;
258}
259
260static int __init set_uml_dir(char *name, int *add)
261{
262 if((strlen(name) > 0) && (name[strlen(name) - 1] != '/')){
263 uml_dir = malloc(strlen(name) + 2);
264 if(uml_dir == NULL){
265 printf("Failed to malloc uml_dir - error = %d\n",
266 errno);
267 uml_dir = name;
268 /* Return 0 here because do_initcalls doesn't look at
269 * the return value.
270 */
271 return(0);
272 }
273 sprintf(uml_dir, "%s/", name);
274 }
275 else uml_dir = name;
276 return(0);
277}
278
279__uml_setup("uml_dir=", set_uml_dir,
280"uml_dir=<directory>\n"
281" The location to place the pid and umid files.\n\n"
282);
283
284static void remove_umid_dir(void)
285{
286 char dir[strlen(uml_dir) + UMID_LEN + 1];
287
288 sprintf(dir, "%s%s", uml_dir, umid);
289 actually_do_remove(dir);
290}
291
292__uml_exitcall(remove_umid_dir);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-08 17:28:30 -0500