#include <sys/param.h>
+/* Modified by which_tmpdir, which is called during early boot */
static char *default_tmpdir = "/tmp";
+
+/*
+ * Modified when creating the physical memory file and when checking
+ * the tmp filesystem for usability, both happening during early boot.
+ */
static char *tempdir = NULL;
static void __init find_tempdir(void)
int i;
char *dir = NULL;
- if(tempdir != NULL) return; /* We've already been called */
+ if(tempdir != NULL) /* We've already been called */
+ return;
for(i = 0; dirs[i]; i++){
dir = getenv(dirs[i]);
if((dir != NULL) && (*dir != '\0'))
*/
static int next(int fd, char *buf, int size, char c)
{
- int n;
+ int n, len;
char *ptr;
while((ptr = strchr(buf, c)) == NULL){
}
ptr++;
- memmove(buf, ptr, strlen(ptr) + 1);
+ len = strlen(ptr);
+ memmove(buf, ptr, len + 1);
+
+ /* Refill the buffer so that if there's a partial string that we care
+ * about, it will be completed, and we can recognize it.
+ */
+ n = read(fd, &buf[len], size - len - 1);
+ if(n < 0)
+ return -errno;
+
+ buf[len + n] = '\0';
return 1;
}
+/* which_tmpdir is called only during early boot */
static int checked_tmpdir = 0;
/* Look for a tmpfs mounted at /dev/shm. I couldn't find a cleaner
}
while(1){
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), ' ');
+ found = next(fd, buf, ARRAY_SIZE(buf), ' ');
if(found != 1)
break;
if(!strncmp(buf, "/dev/shm", strlen("/dev/shm")))
goto found;
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), '\n');
+ found = next(fd, buf, ARRAY_SIZE(buf), '\n');
if(found != 1)
break;
}
else if(found < 0)
printf("read returned errno %d\n", -found);
+out:
+ close(fd);
+
return;
found:
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), ' ');
+ found = next(fd, buf, ARRAY_SIZE(buf), ' ');
if(found != 1)
goto err;
if(strncmp(buf, "tmpfs", strlen("tmpfs"))){
printf("not tmpfs\n");
- return;
+ goto out;
}
printf("OK\n");
default_tmpdir = "/dev/shm";
+ goto out;
}
/*
} else {
free(tempname);
}
- return(fd);
+ return fd;
out:
free(tempname);
return -1;
exit(1);
}
- if (lseek64(fd, len, SEEK_SET) < 0) {
- perror("os_seek_file");
+ /* Seek to len - 1 because writing a character there will
+ * increase the file size by one byte, to the desired length.
+ */
+ if (lseek64(fd, len - 1, SEEK_SET) < 0) {
+ perror("os_seek_file");
exit(1);
}
exit(1);
}
- return(fd);
+ return fd;
}
int create_mem_file(unsigned long long len)
errno = -err;
perror("exec_close");
}
- return(fd);
+ return fd;
}