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/* $Id$ */
#include "bbs.h"
int tune(int num) {
int i, j, fin, fout;
userec_t u;
if((fin = open(FN_PASSWD, O_RDONLY)) == -1) {
perror(FN_PASSWD);
return 1;
}
if(flock(fin, LOCK_EX)) {
printf("Lock failed!\n");
return 1;
}
if((fout = open(FN_PASSWD ".tune" , O_WRONLY | O_CREAT, 0600)) == -1) {
perror(FN_PASSWD ".tune");
flock(fin, LOCK_UN);
close(fin);
return 1;
}
for(i = j = 0; i < num; i++) {
read(fin, &u, sizeof(u));
if(u.userid[0]) {
if(j == MAX_USERS) {
printf("MAX_USERS is too small!\n");
close(fout);
unlink(FN_PASSWD ".tune");
flock(fin, LOCK_UN);
close(fin);
return 1;
}
write(fout, &u, sizeof(u));
j++;
}
}
for(memset(&u, 0, sizeof(u)); j < MAX_USERS; j++) {
write(fout, &u, sizeof(u));
}
close(fout);
/* backup */
unlink(FN_PASSWD "~");
link(FN_PASSWD, FN_PASSWD "~");
unlink(FN_PASSWD);
link(FN_PASSWD ".tune", FN_PASSWD);
unlink(FN_PASSWD ".tune");
flock(fin, LOCK_UN);
close(fin);
return 0;
}
int main() {
struct stat sb;
if(stat(FN_PASSWD, &sb)) {
perror("stat");
return 1;
}
if(sb.st_size != sizeof(userec_t) * MAX_USERS) {
printf("size and MAX_USERS do not match!\n");
if(tune(sb.st_size / sizeof(userec_t)) == 0)
printf(FN_PASSWD " has been tuned successfully!\n");
} else
printf("Nothing to do.\n");
return 0;
}
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