Commit | Line | Data |
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eef6548c BJ |
1 | /* @(#)ulockf 2.3 5/18/79 11:52:11 */ |
2 | #include "uucp.h" | |
3 | #include <sys/types.h> | |
4 | #include <sys/stat.h> | |
5 | ||
6 | char Sulockf[] = "@(#)ulockf 2.3"; | |
7 | ||
8 | ||
9 | /******* | |
10 | * ulockf(file, atime) | |
11 | * char *file; | |
12 | * time_t atime; | |
13 | * | |
14 | * ulockf - this routine will create a lock file (file). | |
15 | * If one already exists, the create time is checked for | |
16 | * older than the age time (atime). | |
17 | * If it is older, an attempt will be made to unlink it | |
18 | * and create a new one. | |
19 | * | |
20 | * return codes: 0 | FAIL | |
21 | */ | |
22 | ||
23 | ulockf(file, atime) | |
24 | char *file; | |
25 | time_t atime; | |
26 | { | |
27 | struct stat stbuf; | |
28 | time_t ptime; | |
29 | int ret; | |
30 | static int pid = -1; | |
31 | static char tempfile[NAMESIZE]; | |
32 | ||
33 | if (pid < 0) { | |
34 | pid = getpid(); | |
35 | sprintf(tempfile, "LTMP.%d", pid); | |
36 | } | |
37 | if (onelock(pid, tempfile, file) == -1) { | |
38 | /* lock file exists */ | |
39 | /* get status to check age of the lock file */ | |
40 | ret = stat(file, &stbuf); | |
41 | if (ret != -1) { | |
42 | time(&ptime); | |
43 | if ((ptime - stbuf.st_ctime) < atime) { | |
44 | /* file not old enough to delete */ | |
45 | return(FAIL); | |
46 | } | |
47 | } | |
48 | ret = unlink(file); | |
49 | ret = onelock(pid, tempfile, file); | |
50 | if (ret != 0) | |
51 | return(FAIL); | |
52 | } | |
53 | stlock(file); | |
54 | return(0); | |
55 | } | |
56 | ||
57 | ||
58 | #define MAXLOCKS 10 /* maximum number of lock files */ | |
59 | char *Lockfile[MAXLOCKS]; | |
60 | int Nlocks = 0; | |
61 | ||
62 | /*** | |
63 | * stlock(name) put name in list of lock files | |
64 | * char *name; | |
65 | * | |
66 | * return codes: none | |
67 | */ | |
68 | ||
69 | stlock(name) | |
70 | char *name; | |
71 | { | |
72 | char *p; | |
73 | extern char *calloc(); | |
74 | int i; | |
75 | ||
76 | for (i = 0; i < Nlocks; i++) { | |
77 | if (Lockfile[i] == NULL) | |
78 | break; | |
79 | } | |
80 | ASSERT(i < MAXLOCKS, "TOO MANY LOCKS %d", i); | |
81 | if (i >= Nlocks) | |
82 | i = Nlocks++; | |
83 | p = calloc(strlen(name) + 1, sizeof (char)); | |
84 | ASSERT(p != NULL, "CAN NOT ALLOCATE FOR %s", name); | |
85 | strcpy(p, name); | |
86 | Lockfile[i] = p; | |
87 | return; | |
88 | } | |
89 | ||
90 | ||
91 | /*** | |
92 | * rmlock(name) remove all lock files in list | |
93 | * char *name; or name | |
94 | * | |
95 | * return codes: none | |
96 | */ | |
97 | ||
98 | rmlock(name) | |
99 | char *name; | |
100 | { | |
101 | int i; | |
102 | ||
103 | for (i = 0; i < Nlocks; i++) { | |
104 | if (Lockfile[i] == NULL) | |
105 | continue; | |
106 | if (name == NULL | |
107 | || strcmp(name, Lockfile[i]) == SAME) { | |
108 | unlink(Lockfile[i]); | |
109 | free(Lockfile[i]); | |
110 | Lockfile[i] = NULL; | |
111 | } | |
112 | } | |
113 | return; | |
114 | } | |
115 | ||
116 | ||
117 | /* this stuff from pjw */ | |
118 | /* /usr/pjw/bin/recover - check pids to remove unnecessary locks */ | |
119 | /* isalock(name) returns 0 if the name is a lock */ | |
120 | /* unlock(name) unlocks name if it is a lock*/ | |
121 | /* onelock(pid,tempfile,name) makes lock a name | |
122 | on behalf of pid. Tempfile must be in the same | |
123 | file system as name. */ | |
124 | /* lock(pid,tempfile,names) either locks all the | |
125 | names or none of them */ | |
126 | isalock(name) char *name; | |
127 | { | |
128 | struct stat xstat; | |
129 | if(stat(name,&xstat)<0) return(0); | |
130 | if(xstat.st_size!=sizeof(int)) return(0); | |
131 | return(1); | |
132 | } | |
133 | unlock(name) char *name; | |
134 | { | |
135 | if(isalock(name)) return(unlink(name)); | |
136 | else return(-1); | |
137 | } | |
138 | onelock(pid,tempfile,name) char *tempfile,*name; | |
139 | { int fd; | |
140 | fd=creat(tempfile,0444); | |
141 | if(fd<0) return(-1); | |
142 | write(fd,&pid,sizeof(int)); | |
143 | close(fd); | |
144 | if(link(tempfile,name)<0) | |
145 | { unlink(tempfile); | |
146 | return(-1); | |
147 | } | |
148 | unlink(tempfile); | |
149 | return(0); | |
150 | } | |
151 | lock(pid,tempfile,names) char *tempfile,**names; | |
152 | { int i,j; | |
153 | for(i=0;names[i]!=0;i++) | |
154 | { if(onelock(pid,tempfile,names[i])==0) continue; | |
155 | for(j=0;j<i;j++) unlink(names[j]); | |
156 | return(-1); | |
157 | } | |
158 | return(0); | |
159 | } | |
160 | ||
161 | #define LOCKPRE "LCK." | |
162 | ||
163 | /*** | |
164 | * delock(s) remove a lock file | |
165 | * char *s; | |
166 | * | |
167 | * return codes: 0 | FAIL | |
168 | */ | |
169 | ||
170 | delock(s) | |
171 | char *s; | |
172 | { | |
173 | char ln[30]; | |
174 | ||
175 | sprintf(ln, "%s.%s", LOCKPRE, s); | |
176 | rmlock(ln); | |
177 | } | |
178 | ||
179 | ||
180 | /*** | |
181 | * mlock(sys) create system lock | |
182 | * char *sys; | |
183 | * | |
184 | * return codes: 0 | FAIL | |
185 | */ | |
186 | ||
187 | mlock(sys) | |
188 | char *sys; | |
189 | { | |
190 | char lname[30]; | |
191 | sprintf(lname, "%s.%s", LOCKPRE, sys); | |
192 | return(ulockf(lname, (time_t) 5400 ) < 0 ? FAIL : 0); | |
193 | } | |
194 | ||
195 | ||
196 | ||
197 | /*** | |
198 | * ultouch() update access and modify times for lock files | |
199 | * | |
200 | * return code - none | |
201 | */ | |
202 | ||
203 | ultouch() | |
204 | { | |
205 | time_t time(), ptime; | |
206 | int i; | |
207 | struct ut { | |
208 | time_t actime; | |
209 | time_t modtime; | |
210 | } ut; | |
211 | ||
212 | ut.actime = time(&ut.modtime); | |
213 | for (i = 0; i < Nlocks; i++) { | |
214 | if (Lockfile[i] == NULL) | |
215 | continue; | |
216 | utime(Lockfile[i], &ut); | |
217 | } | |
218 | return; | |
219 | } |