diff options
Diffstat (limited to 'arch/um/os-Linux')
| -rw-r--r-- | arch/um/os-Linux/Makefile | 4 | ||||
| -rw-r--r-- | arch/um/os-Linux/umid.c | 292 |
2 files changed, 294 insertions, 2 deletions
diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index b83ac8e21c3..11e30b13e31 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -4,11 +4,11 @@ # obj-y = aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \ - start_up.o time.o tt.o tty.o uaccess.o user_syms.o drivers/ \ + start_up.o time.o tt.o tty.o uaccess.o umid.o user_syms.o drivers/ \ sys-$(SUBARCH)/ USER_OBJS := aio.o elf_aux.o file.o helper.o main.o mem.o process.o signal.o \ - start_up.o time.o tt.o tty.o uaccess.o + start_up.o time.o tt.o tty.o uaccess.o umid.o elf_aux.o: $(ARCH_DIR)/kernel-offsets.h CFLAGS_elf_aux.o += -I$(objtree)/arch/um diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c new file mode 100644 index 00000000000..77d69a348cf --- /dev/null +++ b/arch/um/os-Linux/umid.c @@ -0,0 +1,292 @@ +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <signal.h> +#include <dirent.h> +#include <sys/stat.h> +#include <sys/param.h> +#include "init.h" +#include "os.h" +#include "user.h" +#include "mode.h" + +#define UML_DIR "~/.uml/" + +#define UMID_LEN 64 + +/* Changed by set_umid, which is run early in boot */ +char umid[UMID_LEN] = { 0 }; + +/* Changed by set_uml_dir and make_uml_dir, which are run early in boot */ +static char *uml_dir = UML_DIR; + +static int __init make_uml_dir(void) +{ + char dir[512] = { '\0' }; + int len; + + if(*uml_dir == '~'){ + char *home = getenv("HOME"); + + if(home == NULL){ + printf("make_uml_dir : no value in environment for " + "$HOME\n"); + exit(1); + } + strlcpy(dir, home, sizeof(dir)); + uml_dir++; + } + strlcat(dir, uml_dir, sizeof(dir)); + len = strlen(dir); + if (len > 0 && dir[len - 1] != '/') + strlcat(dir, "/", sizeof(dir)); + + uml_dir = malloc(strlen(dir) + 1); + if (uml_dir == NULL) { + printf("make_uml_dir : malloc failed, errno = %d\n", errno); + exit(1); + } + strcpy(uml_dir, dir); + + if((mkdir(uml_dir, 0777) < 0) && (errno != EEXIST)){ + printf("Failed to mkdir '%s': %s\n", uml_dir, strerror(errno)); + return(-1); + } + return 0; +} + +static int actually_do_remove(char *dir) +{ + DIR *directory; + struct dirent *ent; + int len; + char file[256]; + + directory = opendir(dir); + if(directory == NULL){ + printk("actually_do_remove : couldn't open directory '%s', " + "errno = %d\n", dir, errno); + return(1); + } + while((ent = readdir(directory)) != NULL){ + if(!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, "..")) + continue; + len = strlen(dir) + sizeof("/") + strlen(ent->d_name) + 1; + if(len > sizeof(file)){ + printk("Not deleting '%s' from '%s' - name too long\n", + ent->d_name, dir); + continue; + } + sprintf(file, "%s/%s", dir, ent->d_name); + if(unlink(file) < 0){ + printk("actually_do_remove : couldn't remove '%s' " + "from '%s', errno = %d\n", ent->d_name, dir, + errno); + return(1); + } + } + if(rmdir(dir) < 0){ + printk("actually_do_remove : couldn't rmdir '%s', " + "errno = %d\n", dir, errno); + return(1); + } + return(0); +} + +extern int tracing_pid; + +static int not_dead_yet(char *dir) +{ + char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")]; + char pid[sizeof("nnnnn\0")], *end; + int dead, fd, p, n; + + sprintf(file, "%s/pid", dir); + dead = 0; + fd = os_open_file(file, of_read(OPENFLAGS()), 0); + if(fd < 0){ + if(fd != -ENOENT){ + printk("not_dead_yet : couldn't open pid file '%s', " + "err = %d\n", file, -fd); + return(1); + } + dead = 1; + } + if(fd > 0){ + n = os_read_file(fd, pid, sizeof(pid)); + if(n < 0){ + printk("not_dead_yet : couldn't read pid file '%s', " + "err = %d\n", file, -n); + return(1); + } + p = strtoul(pid, &end, 0); + if(end == pid){ + printk("not_dead_yet : couldn't parse pid file '%s', " + "errno = %d\n", file, errno); + dead = 1; + } + if(((kill(p, 0) < 0) && (errno == ESRCH)) || + (p == CHOOSE_MODE(tracing_pid, os_getpid()))) + dead = 1; + } + if(!dead) + return(1); + return(actually_do_remove(dir)); +} + +static void __init create_pid_file(void) +{ + char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")]; + char pid[sizeof("nnnnn\0")]; + int fd, n; + + if(umid_file_name("pid", file, sizeof(file))) + return; + + fd = os_open_file(file, of_create(of_excl(of_rdwr(OPENFLAGS()))), + 0644); + if(fd < 0){ + printf("Open of machine pid file \"%s\" failed: %s\n", + file, strerror(-fd)); + return; + } + + sprintf(pid, "%d\n", os_getpid()); + n = os_write_file(fd, pid, strlen(pid)); + if(n != strlen(pid)) + printf("Write of pid file failed - err = %d\n", -n); + os_close_file(fd); +} + +int __init set_umid(char *name, int (*printer)(const char *fmt, ...)) +{ + if(strlen(name) > UMID_LEN - 1) + (*printer)("Unique machine name is being truncated to %d " + "characters\n", UMID_LEN); + strlcpy(umid, name, sizeof(umid)); + + return 0; +} + +static int umid_setup = 0; + +int __init make_umid(int (*printer)(const char *fmt, ...)) +{ + int fd, err; + char tmp[256]; + + make_uml_dir(); + + if(*umid == '\0'){ + strlcpy(tmp, uml_dir, sizeof(tmp)); + strcat(tmp, "XXXXXX"); + fd = mkstemp(tmp); + if(fd < 0){ + (*printer)("make_umid - mkstemp(%s) failed: %s\n", + tmp,strerror(errno)); + return(1); + } + + os_close_file(fd); + /* There's a nice tiny little race between this unlink and + * the mkdir below. It'd be nice if there were a mkstemp + * for directories. + */ + unlink(tmp); + set_umid(&tmp[strlen(uml_dir)], printer); + } + + sprintf(tmp, "%s%s", uml_dir, umid); + err = mkdir(tmp, 0777); + if(err < 0){ + if(errno == EEXIST){ + if(not_dead_yet(tmp)) + return -EEXIST; + err = mkdir(tmp, 0777); + } + } + if(err < 0){ + (*printer)("Failed to create %s - errno = %d\n", umid, errno); + return(-1); + } + + umid_setup = 1; + + create_pid_file(); + + return 0; +} + +static int __init make_umid_init(void) +{ + make_umid(printk); + + return(0); +} + +__initcall(make_umid_init); + +int __init umid_file_name(char *name, char *buf, int len) +{ + int n, err; + + if(!umid_setup){ + err = make_umid(printk); + if(err) + return err; + } + + n = strlen(uml_dir) + strlen(umid) + strlen("/") + strlen(name) + 1; + if(n > len){ + printk("umid_file_name : buffer too short\n"); + return(-1); + } + + sprintf(buf, "%s%s/%s", uml_dir, umid, name); + return(0); +} + +extern int umid_is_random; + +char *get_umid(int only_if_set) +{ + if(only_if_set && umid_is_random) + return NULL; + return umid; +} + +static int __init set_uml_dir(char *name, int *add) +{ + if((strlen(name) > 0) && (name[strlen(name) - 1] != '/')){ + uml_dir = malloc(strlen(name) + 2); + if(uml_dir == NULL){ + printf("Failed to malloc uml_dir - error = %d\n", + errno); + uml_dir = name; + /* Return 0 here because do_initcalls doesn't look at + * the return value. + */ + return(0); + } + sprintf(uml_dir, "%s/", name); + } + else uml_dir = name; + return(0); +} + +__uml_setup("uml_dir=", set_uml_dir, +"uml_dir=<directory>\n" +" The location to place the pid and umid files.\n\n" +); + +static void remove_umid_dir(void) +{ + char dir[strlen(uml_dir) + UMID_LEN + 1]; + + sprintf(dir, "%s%s", uml_dir, umid); + actually_do_remove(dir); +} + +__uml_exitcall(remove_umid_dir); |