char *xmalloc_readlink_or_warn(const char *path);
char *xmalloc_realpath(const char *path);
extern void xstat(const char *filename, struct stat *buf);
-extern pid_t spawn(char **argv);
-extern pid_t xspawn(char **argv);
extern int wait4pid(int pid);
extern void xsetgid(gid_t gid);
extern void xsetuid(uid_t uid);
-extern void xdaemon(int nochdir, int noclose);
-/* More clever/thorough xdaemon */
-extern void bb_sanitize_stdio_maybe_daemonize(int daemonize);
-extern void bb_sanitize_stdio(void);
-/* NB: be careful: dont open syslog/network sockets before bb_daemonize */
-extern void bb_daemonize(void);
extern void xchdir(const char *path);
extern void xsetenv(const char *key, const char *value);
extern int xopen(const char *pathname, int flags);
enum { USERNAME_MAX_SIZE = 16 - sizeof(int) };
+int execable_file(const char *name);
+char *find_execable(const char *filename);
+int exists_execable(const char *filename);
+
+#if ENABLE_FEATURE_EXEC_PREFER_APPLETS
+int bb_execvp(const char *file, char *const argv[]);
+#define BB_EXECVP(prog,cmd) bb_execvp(prog,cmd)
+#define BB_EXECLP(prog,cmd,...) \
+ execlp((find_applet_by_name(prog)) ? CONFIG_BUSYBOX_EXEC_PATH : prog, \
+ cmd, __VA_ARGS__)
+#else
+#define BB_EXECVP(prog,cmd) execvp(prog,cmd)
+#define BB_EXECLP(prog,cmd,...) execlp(prog,cmd, __VA_ARGS__)
+#endif
+
+/* NOMMU friendy fork+exec */
+pid_t spawn(char **argv);
+pid_t xspawn(char **argv);
+/* Helpers for daemonization.
+ * bb_daemonize(flags) = daemonize, does not compile on NOMMU
+ * bb_daemonize_or_rexec(flags, argv) = daemonizes on MMU (and ignores argv),
+ * rexec's itself on NOMMU with argv passed as command line.
+ * Thus bb_daemonize_or_rexec may cause your <applet>_main() to be re-executed
+ * from the start. (It will detect it and not reexec again second time).
+ * You have to audit carefully that you don't do something twice as a result
+ * (opening files/sockets, parsing config files etc...)!
+ *
+ * Both of the above will redirect fd 0,1,2 to /dev/null and drop ctty
+ * (will do setsid()).
+ *
+ * Helper for network daemons in foreground mode:
+ * bb_sanitize_stdio() = make sure that fd 0,1,2 are opened by opening them
+ * to /dev/null if they are not.
+ */
+enum {
+ DAEMON_CHDIR_ROOT = 1,
+ DAEMON_DEVNULL_STDIO = /* 2 */ 0, /* no users so far */
+ DAEMON_CLOSE_EXTRA_FDS = 4,
+ DAEMON_ONLY_SANITIZE = 8, /* internal use */
+};
+#ifndef BB_NOMMU
+#define bb_daemonize_or_rexec(flags, argv) bb_daemonize_or_rexec(flags)
+#define bb_daemonize(flags) bb_daemonize_or_rexec(flags, bogus)
+#else
+extern smallint re_execed;
+pid_t BUG_fork_is_unavailable_on_nommu(void);
+pid_t BUG_daemon_is_unavailable_on_nommu(void);
+pid_t BUG_bb_daemonize_is_unavailable_on_nommu(void);
+#define fork() BUG_fork_is_unavailable_on_nommu()
+#define daemon(a,b) BUG_daemon_is_unavailable_on_nommu()
+#define bb_daemonize(a) BUG_bb_daemonize_is_unavailable_on_nommu()
+#endif
+void bb_daemonize_or_rexec(int flags, char **argv);
+void bb_sanitize_stdio(void);
+
+
enum { BB_GETOPT_ERROR = 0x80000000 };
extern const char *opt_complementary;
#if ENABLE_GETOPT_LONG
char *concat_subpath_file(const char *path, const char *filename);
char *last_char_is(const char *s, int c);
-int execable_file(const char *name);
-char *find_execable(const char *filename);
-int exists_execable(const char *filename);
-
-#if ENABLE_FEATURE_EXEC_PREFER_APPLETS
-int bb_execvp(const char *file, char *const argv[]);
-#define BB_EXECVP(prog,cmd) bb_execvp(prog,cmd)
-#define BB_EXECLP(prog,cmd,...) \
- execlp((find_applet_by_name(prog)) ? CONFIG_BUSYBOX_EXEC_PATH : prog, \
- cmd, __VA_ARGS__)
-#else
-#define BB_EXECVP(prog,cmd) execvp(prog,cmd)
-#define BB_EXECLP(prog,cmd,...) execlp(prog,cmd, __VA_ARGS__)
-#endif
USE_DESKTOP(long long) int uncompress(int fd_in, int fd_out);
int inflate(int in, int out);
extern int index_in_substr_array(const char * const string_array[], const char *key);
extern void print_login_issue(const char *issue_file, const char *tty);
extern void print_login_prompt(void);
-#ifdef BB_NOMMU
-extern pid_t BUG_fork_is_unavailable_on_nommu(void);
-#define fork() BUG_fork_is_unavailable_on_nommu()
-extern void vfork_daemon_rexec(int nochdir, int noclose, char **argv);
-extern smallint re_execed;
-#endif
+
+
extern int get_terminal_width_height(const int fd, int *width, int *height);
char *is_in_ino_dev_hashtable(const struct stat *statbuf);
#include <paths.h>
#include "libbb.h"
-#ifdef BB_NOMMU
+/* This does a fork/exec in one call, using vfork(). Returns PID of new child,
+ * -1 for failure. Runs argv[0], searching path if that has no / in it. */
+pid_t spawn(char **argv)
+{
+ /* Compiler should not optimize stores here */
+ volatile int failed;
+ pid_t pid;
+
+ // Be nice to nommu machines.
+ failed = 0;
+ pid = vfork();
+ if (pid < 0) /* error */
+ return pid;
+ if (!pid) { /* child */
+ /* Don't use BB_EXECVP tricks here! */
+ execvp(argv[0], argv);
+
+ /* We are (maybe) sharing a stack with blocked parent,
+ * let parent know we failed and then exit to unblock parent
+ * (but don't run atexit() stuff, which would screw up parent.)
+ */
+ failed = errno;
+ _exit(0);
+ }
+ /* parent */
+ /* Unfortunately, this is not reliable: vfork()
+ * can be equivalent to fork() according to standards */
+ if (failed) {
+ errno = failed;
+ return -1;
+ }
+ return pid;
+}
+
+/* Die with an error message if we can't spawn a child process. */
+pid_t xspawn(char **argv)
+{
+ pid_t pid = spawn(argv);
+ if (pid < 0) bb_perror_msg_and_die("%s", *argv);
+ return pid;
+}
+
+
+
+#if 0 //ndef BB_NOMMU
+// Die with an error message if we can't daemonize.
+void xdaemon(int nochdir, int noclose)
+{
+ if (daemon(nochdir, noclose))
+ bb_perror_msg_and_die("daemon");
+}
+#endif
+
+#if 0 // def BB_NOMMU
void vfork_daemon_rexec(int nochdir, int noclose, char **argv)
{
int fd;
+ /* Maybe we are already re-execed and come here again? */
+ if (re_execed)
+ return;
+
setsid();
if (!nochdir)
}
}
#endif /* BB_NOMMU */
+
+#ifdef BB_NOMMU
+static void daemon_or_rexec(char **argv)
+{
+ pid_t pid;
+ /* Maybe we are already re-execed and come here again? */
+ if (re_execed)
+ return;
+
+ pid = vfork();
+ if (pid < 0) /* wtf? */
+ bb_perror_msg_and_die("vfork");
+ if (pid) /* parent */
+ exit(0);
+ /* child - re-exec ourself */
+ /* high-order bit of first char in argv[0] is a hidden
+ * "we have (alrealy) re-execed, don't do it again" flag */
+ argv[0][0] |= 0x80;
+ execv(CONFIG_BUSYBOX_EXEC_PATH, argv);
+ bb_perror_msg_and_die("exec %s", CONFIG_BUSYBOX_EXEC_PATH);
+}
+#else
+static void daemon_or_rexec(void)
+{
+ pid_t pid;
+ pid = fork();
+ if (pid < 0) /* wtf? */
+ bb_perror_msg_and_die("fork");
+ if (pid) /* parent */
+ exit(0);
+ /* child */
+}
+#define daemon_or_rexec(argv) daemon_or_rexec()
+#endif
+
+
+/* Due to a #define in libbb.h on MMU systems we actually have 1 argument -
+ * char **argv "vanishes" */
+void bb_daemonize_or_rexec(int flags, char **argv)
+{
+ int fd;
+
+ fd = xopen(bb_dev_null, O_RDWR);
+
+ if (flags & DAEMON_CHDIR_ROOT)
+ xchdir("/");
+
+ if (flags & DAEMON_DEVNULL_STDIO) {
+ close(0);
+ close(1);
+ close(2);
+ }
+
+ while ((unsigned)fd < 2)
+ fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
+
+ if (!(flags & DAEMON_ONLY_SANITIZE)) {
+ daemon_or_rexec(argv);
+ /* if daemonizing, make sure we detach from stdio */
+ setsid();
+ dup2(fd, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+ }
+ if (fd > 2)
+ close(fd--);
+ if (flags & DAEMON_CLOSE_EXTRA_FDS)
+ while (fd > 2)
+ close(fd--); /* close everything after fd#2 */
+}
+
+void bb_sanitize_stdio(void)
+{
+ bb_daemonize_or_rexec(DAEMON_ONLY_SANITIZE, NULL);
+}
}
}
-// This does a fork/exec in one call, using vfork(). Return PID of new child,
-// -1 for failure. Runs argv[0], searching path if that has no / in it.
-pid_t spawn(char **argv)
-{
- /* Why static? */
- static int failed;
- pid_t pid;
-
- // Be nice to nommu machines.
- failed = 0;
- pid = vfork();
- if (pid < 0) return pid;
- if (!pid) {
- BB_EXECVP(argv[0], argv);
-
- // We're sharing a stack with blocked parent, let parent know we failed
- // and then exit to unblock parent (but don't run atexit() stuff, which
- // would screw up parent.)
-
- failed = errno;
- _exit(0);
- }
- if (failed) {
- errno = failed;
- return -1;
- }
- return pid;
-}
-
-// Die with an error message if we can't spawn a child process.
-pid_t xspawn(char **argv)
-{
- pid_t pid = spawn(argv);
- if (pid < 0) bb_perror_msg_and_die("%s", *argv);
- return pid;
-}
-
// Wait for the specified child PID to exit, returning child's error return.
int wait4pid(int pid)
{
return dp;
}
-#ifndef BB_NOMMU
-// Die with an error message if we can't daemonize.
-void xdaemon(int nochdir, int noclose)
-{
- if (daemon(nochdir, noclose))
- bb_perror_msg_and_die("daemon");
-}
-#endif
-
-void bb_sanitize_stdio_maybe_daemonize(int daemonize)
-{
- int fd;
- /* Mega-paranoid */
- fd = xopen(bb_dev_null, O_RDWR);
- while ((unsigned)fd < 2)
- fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
- if (daemonize) {
- pid_t pid = fork();
- if (pid < 0) /* wtf? */
- bb_perror_msg_and_die("fork");
- if (pid) /* parent */
- exit(0);
- /* child */
- /* if daemonizing, make sure we detach from stdio */
- setsid();
- dup2(fd, 0);
- dup2(fd, 1);
- dup2(fd, 2);
- }
- while (fd > 2)
- close(fd--); /* close everything after fd#2 */
-}
-void bb_sanitize_stdio(void)
-{
- bb_sanitize_stdio_maybe_daemonize(0);
-}
-void bb_daemonize(void)
-{
- bb_sanitize_stdio_maybe_daemonize(1);
-}
-
// Die with an error message if we can't open a new socket.
int xsocket(int domain, int type, int protocol)
{
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