1 files changed, 292 insertions, 0 deletions

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 @@
+#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);