Compatibility fixes:

grep: support -z
find: support --mindepth
  together +45 bytes
cpio: support -p (configurable, +230 bytes)
libbb: tweaks for cpio

10 files changed, 137 insertions, 59 deletions

diff --git a/TODO_config_nommu b/TODO_config_nommu
index 428d9b300..2061bfd1c 100644
--- a/TODO_config_nommu
+++ b/TODO_config_nommu
@@ -110,6 +110,7 @@ CONFIG_BUNZIP2=y
 CONFIG_BZIP2=y
 CONFIG_CPIO=y
 CONFIG_FEATURE_CPIO_O=y
+CONFIG_FEATURE_CPIO_P=y
 CONFIG_DPKG=y
 CONFIG_DPKG_DEB=y
 CONFIG_FEATURE_DPKG_DEB_EXTRACT_ONLY=y
diff --git a/archival/Config.in b/archival/Config.in
index 0b5cf3750..64b44c218 100644
--- a/archival/Config.in
+++ b/archival/Config.in
@@ -110,6 +110,13 @@ config FEATURE_CPIO_O
           This implementation of cpio can create cpio archives in the "newc"
           format only.
 
+config FEATURE_CPIO_P
+        bool "Support for passthrough mode"
+        default n
+        depends on FEATURE_CPIO_O
+        help
+          Passthrough mode. Rarely used.
+
 config DPKG
         bool "dpkg"
         default n
diff --git a/archival/cpio.c b/archival/cpio.c
index 1c30d89a8..929d544ff 100644
--- a/archival/cpio.c
+++ b/archival/cpio.c
@@ -259,8 +259,9 @@ int cpio_main(int argc UNUSED_PARAM, char **argv)
                 CPIO_OPT_FILE               = (1 << 4),
                 CPIO_OPT_CREATE_LEADING_DIR = (1 << 5),
                 CPIO_OPT_PRESERVE_MTIME     = (1 << 6),
-                CPIO_OPT_CREATE             = (1 << 7),
-                CPIO_OPT_FORMAT             = (1 << 8),
+                CPIO_OPT_CREATE             = (1 << 7) * ENABLE_FEATURE_CPIO_O,
+                CPIO_OPT_FORMAT             = (1 << 8) * ENABLE_FEATURE_CPIO_O,
+                CPIO_OPT_PASSTHROUGH        = (1 << 9) * ENABLE_FEATURE_CPIO_P,
         };
 
 #if ENABLE_GETOPT_LONG
@@ -270,21 +271,66 @@ int cpio_main(int argc UNUSED_PARAM, char **argv)
 #if ENABLE_FEATURE_CPIO_O
                 "create\0"       No_argument       "o"
                 "format\0"       Required_argument "H"
+#if ENABLE_FEATURE_CPIO_P
+                "pass-through\0" No_argument       "p"
+#endif
 #endif
                 ;
 #endif
 
-        /* Initialize */
-        archive_handle = init_handle();
-        archive_handle->src_fd = STDIN_FILENO;
-        archive_handle->seek = seek_by_read;
-        archive_handle->ah_flags = ARCHIVE_EXTRACT_NEWER;
-
-#if ENABLE_FEATURE_CPIO_O
-        opt = getopt32(argv, "ituvF:dmoH:", &cpio_filename, &cpio_fmt);
+        /* As of now we do not enforce this: */
+        /* -i,-t,-o,-p are mutually exclusive */
+        /* -u,-d,-m make sense only with -i or -p */
+        /* -F makes sense only with -o */
+#if !ENABLE_FEATURE_CPIO_O
+        opt = getopt32(argv, "ituvF:dm", &cpio_filename);
+#else
+        opt = getopt32(argv, "ituvF:dmoH:" USE_FEATURE_CPIO_P("p"), &cpio_filename, &cpio_fmt);
+        if (opt & CPIO_OPT_PASSTHROUGH) {
+                pid_t pid;
+                struct fd_pair pp;
 
+                if (argv[optind] == NULL)
+                        bb_show_usage();
+                if (opt & CPIO_OPT_CREATE_LEADING_DIR)
+                        mkdir(argv[optind], 0777);
+                /* Crude existence check:
+                 * close(xopen(argv[optind], O_RDONLY | O_DIRECTORY));
+                 * We can also xopen, fstat, IS_DIR, later fchdir.
+                 * This would check for existence earlier and cleaner.
+                 * As it stands now, if we fail xchdir later,
+                 * child dies on EPIPE, unless it caught
+                 * a diffrerent problem earlier.
+                 * This is good enough for now.
+                 */
+#if !BB_MMU
+                pp.rd = 3;
+                pp.wr = 4;
+                if (!re_execed) {
+                        close(3);
+                        close(4);
+                        xpiped_pair(pp);
+                }
+#else
+                xpiped_pair(pp);
+#endif
+                pid = fork_or_rexec(argv);
+                if (pid == 0) { /* child */
+                        close(pp.rd);
+                        xmove_fd(pp.wr, STDOUT_FILENO);
+                        goto dump;
+                }
+                /* parent */
+                xchdir(argv[optind++]);
+                close(pp.wr);
+                xmove_fd(pp.rd, STDIN_FILENO);
+                opt &= ~CPIO_OPT_PASSTHROUGH;
+                opt |= CPIO_OPT_EXTRACT;
+                goto skip;
+        }
+        /* -o */
         if (opt & CPIO_OPT_CREATE) {
-                if (*cpio_fmt != 'n')
+                if (*cpio_fmt != 'n') /* we _require_ "-H newc" */
                         bb_show_usage();
                 if (opt & CPIO_OPT_FILE) {
                         fclose(stdout);
@@ -292,13 +338,18 @@ int cpio_main(int argc UNUSED_PARAM, char **argv)
                         /* Paranoia: I don't trust libc that much */
                         xdup2(fileno(stdout), STDOUT_FILENO);
                 }
+ dump:
                 return cpio_o();
         }
-#else
-        opt = getopt32(argv, "ituvF:dm", &cpio_filename);
+ skip:
 #endif
         argv += optind;
 
+        archive_handle = init_handle();
+        archive_handle->src_fd = STDIN_FILENO;
+        archive_handle->seek = seek_by_read;
+        archive_handle->ah_flags = ARCHIVE_EXTRACT_NEWER;
+
         /* One of either extract or test options must be given */
         if ((opt & (CPIO_OPT_TEST | CPIO_OPT_EXTRACT)) == 0) {
                 bb_show_usage();
@@ -306,9 +357,7 @@ int cpio_main(int argc UNUSED_PARAM, char **argv)
 
         if (opt & CPIO_OPT_TEST) {
                 /* if both extract and test options are given, ignore extract option */
-                if (opt & CPIO_OPT_EXTRACT) {
-                        opt &= ~CPIO_OPT_EXTRACT;
-                }
+                opt &= ~CPIO_OPT_EXTRACT;
                 archive_handle->action_header = header_list;
         }
         if (opt & CPIO_OPT_EXTRACT) {
diff --git a/findutils/find.c b/findutils/find.c
index f2b89746f..df632f219 100644
--- a/findutils/find.c
+++ b/findutils/find.c
@@ -381,9 +381,11 @@ static int FAST_FUNC fileAction(const char *fileName,
 {
         int i;
 #if ENABLE_FEATURE_FIND_MAXDEPTH
-        int maxdepth = (int)(ptrdiff_t)userData;
+#define minmaxdepth ((int*)userData)
 
-        if (depth > maxdepth) return SKIP;
+        if (depth < minmaxdepth[0]) return TRUE;
+        if (depth > minmaxdepth[1]) return SKIP;
+#undef minmaxdepth
 #endif
 
 #if ENABLE_FEATURE_FIND_XDEV
@@ -812,19 +814,21 @@ int find_main(int argc, char **argv)
         static const char options[] ALIGN1 =
                           "-follow\0"
 USE_FEATURE_FIND_XDEV(    "-xdev\0"    )
-USE_FEATURE_FIND_MAXDEPTH("-maxdepth\0")
+USE_FEATURE_FIND_MAXDEPTH("-mindepth\0""-maxdepth\0")
                           ;
         enum {
                           OPT_FOLLOW,
 USE_FEATURE_FIND_XDEV(    OPT_XDEV    ,)
-USE_FEATURE_FIND_MAXDEPTH(OPT_MAXDEPTH,)
+USE_FEATURE_FIND_MAXDEPTH(OPT_MINDEPTH,)
         };
 
         char *arg;
         char **argp;
         int i, firstopt, status = EXIT_SUCCESS;
 #if ENABLE_FEATURE_FIND_MAXDEPTH
-        int maxdepth = INT_MAX;
+        int minmaxdepth[2] = { 0, INT_MAX };
+#else
+#define minmaxdepth NULL
 #endif
 
         for (firstopt = 1; firstopt < argc; firstopt++) {
@@ -875,10 +879,10 @@ USE_FEATURE_FIND_MAXDEPTH(OPT_MAXDEPTH,)
                 }
 #endif
 #if ENABLE_FEATURE_FIND_MAXDEPTH
-                if (opt == OPT_MAXDEPTH) {
+                if (opt == OPT_MINDEPTH || opt == OPT_MINDEPTH + 1) {
                         if (!argp[1])
                                 bb_show_usage();
-                        maxdepth = xatoi_u(argp[1]);
+                        minmaxdepth[opt - OPT_MINDEPTH] = xatoi_u(argp[1]);
                         argp[0] = (char*)"-a";
                         argp[1] = (char*)"-a";
                         argp++;
@@ -895,9 +899,7 @@ USE_FEATURE_FIND_MAXDEPTH(OPT_MAXDEPTH,)
                                 fileAction,     /* file action */
                                 fileAction,     /* dir action */
 #if ENABLE_FEATURE_FIND_MAXDEPTH
-                                /* double cast suppresses
-                                 * "cast to ptr from int of different size" */
-                                (void*)(ptrdiff_t)maxdepth,/* user data */
+                                minmaxdepth,    /* user data */
 #else
                                 NULL,           /* user data */
 #endif
diff --git a/findutils/grep.c b/findutils/grep.c
index 6a6ddb679..723c3511a 100644
--- a/findutils/grep.c
+++ b/findutils/grep.c
@@ -28,7 +28,9 @@
         USE_FEATURE_GREP_CONTEXT("A:B:C:") \
         USE_FEATURE_GREP_EGREP_ALIAS("E") \
         USE_DESKTOP("w") \
+        USE_EXTRA_COMPAT("z") \
         "aI"
+        
 /* ignored: -a "assume all files to be text" */
 /* ignored: -I "assume binary files have no matches" */
 
@@ -54,6 +56,7 @@ enum {
         USE_FEATURE_GREP_CONTEXT(    OPTBIT_C ,) /* -C NUM: -A and -B combined */
         USE_FEATURE_GREP_EGREP_ALIAS(OPTBIT_E ,) /* extended regexp */
         USE_DESKTOP(                 OPTBIT_w ,) /* whole word match */
+        USE_EXTRA_COMPAT(            OPTBIT_z ,) /* input is NUL terminated */
         OPT_l = 1 << OPTBIT_l,
         OPT_n = 1 << OPTBIT_n,
         OPT_q = 1 << OPTBIT_q,
@@ -75,6 +78,7 @@ enum {
         OPT_C = USE_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_C)) + 0,
         OPT_E = USE_FEATURE_GREP_EGREP_ALIAS((1 << OPTBIT_E)) + 0,
         OPT_w = USE_DESKTOP(                 (1 << OPTBIT_w)) + 0,
+        OPT_z = USE_EXTRA_COMPAT(            (1 << OPTBIT_z)) + 0,
 };
 
 #define PRINT_FILES_WITH_MATCHES    (option_mask32 & OPT_l)
@@ -84,6 +88,7 @@ enum {
 #define PRINT_MATCH_COUNTS          (option_mask32 & OPT_c)
 #define FGREP_FLAG                  (option_mask32 & OPT_F)
 #define PRINT_FILES_WITHOUT_MATCHES (option_mask32 & OPT_L)
+#define NUL_DELIMITED               (option_mask32 & OPT_z)
 
 struct globals {
         int max_matches;
@@ -186,7 +191,7 @@ static void print_line(const char *line, size_t line_len, int linenum, char deco
                 puts(line);
 #else
                 fwrite(line, 1, line_len, stdout);
-                putchar('\n');
+                putchar(NUL_DELIMITED ? '\0' : '\n');
 #endif
         }
 }
@@ -197,12 +202,13 @@ static ssize_t FAST_FUNC bb_getline(char **line_ptr, size_t *line_alloc_len, FIL
 {
         ssize_t res_sz;
         char *line;
+        int delim = (NUL_DELIMITED ? '\0' : '\n');
 
-        res_sz = getline(line_ptr, line_alloc_len, file);
+        res_sz = getdelim(line_ptr, line_alloc_len, delim, file);
         line = *line_ptr;
 
         if (res_sz > 0) {
-                if (line[res_sz - 1] == '\n')
+                if (line[res_sz - 1] == delim)
                         line[--res_sz] = '\0';
         } else {
                 free(line); /* uclibc allocates a buffer even on EOF. WTF? */
@@ -407,8 +413,11 @@ static int grep_file(FILE *file)
 #endif
                 /* Did we print all context after last requested match? */
                 if ((option_mask32 & OPT_m)
-                 && !print_n_lines_after && nmatches == max_matches)
+                 && !print_n_lines_after
+                 && nmatches == max_matches
+                ) {
                         break;
+                }
         } /* while (read line) */
 
         /* special-case file post-processing for options where we don't print line
diff --git a/include/libbb.h b/include/libbb.h
index 8ea493b18..a2042fe5c 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -797,9 +797,9 @@ int run_nofork_applet_prime(struct nofork_save_area *old, int applet_no, char **
  * Both of the above will redirect fd 0,1,2 to /dev/null and drop ctty
  * (will do setsid()).
  *
- * forkexit_or_rexec(argv) = bare-bones "fork + parent exits" on MMU,
+ * fork_or_rexec(argv) = bare-bones "fork" on MMU,
  *      "vfork + re-exec ourself" on NOMMU. No fd redirection, no setsid().
- *      Currently used for setsid only. On MMU ignores argv.
+ *      On MMU ignores argv.
  *
  * Helper for network daemons in foreground mode:
  *
@@ -813,14 +813,14 @@ enum {
         DAEMON_ONLY_SANITIZE = 8, /* internal use */
 };
 #if BB_MMU
-  void forkexit_or_rexec(void) FAST_FUNC;
+  pid_t fork_or_rexec(void) FAST_FUNC;
   enum { re_execed = 0 };
-# define forkexit_or_rexec(argv)            forkexit_or_rexec()
+# define fork_or_rexec(argv)                fork_or_rexec()
 # define bb_daemonize_or_rexec(flags, argv) bb_daemonize_or_rexec(flags)
 # define bb_daemonize(flags)                bb_daemonize_or_rexec(flags, bogus)
 #else
   void re_exec(char **argv) NORETURN FAST_FUNC;
-  void forkexit_or_rexec(char **argv) FAST_FUNC;
+  pid_t fork_or_rexec(char **argv) FAST_FUNC;
   extern bool re_execed;
   int  BUG_fork_is_unavailable_on_nommu(void) FAST_FUNC;
   int  BUG_daemon_is_unavailable_on_nommu(void) FAST_FUNC;
diff --git a/include/usage.h b/include/usage.h
index e78754315..2b5d34ea6 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -531,24 +531,29 @@
      "\n        -l,-s   Create (sym)links" \
 
 #define cpio_trivial_usage \
-       "-[dim" USE_FEATURE_CPIO_O("o") "tuv][F cpiofile]" \
-       USE_FEATURE_CPIO_O( "[H newc]" )
+       "-[ti" USE_FEATURE_CPIO_O("o") USE_FEATURE_CPIO_P("p") "dmvu] [-F FILE]" \
+       USE_FEATURE_CPIO_O( " [-H newc]" )
 #define cpio_full_usage "\n\n" \
        "Extract or list files from a cpio archive" \
         USE_FEATURE_CPIO_O( ", or create a cpio archive" ) \
-     "\n" \
-       "Main operation mode:" \
-     "\n        d       Make leading directories" \
-     "\n        i       Extract" \
-     "\n        m       Preserve mtime" \
+     "\nMain operation mode:" \
+     "\n        -t      List" \
+     "\n        -i      Extract" \
         USE_FEATURE_CPIO_O( \
-     "\n        o       Create" \
-     "\n        H newc  Define format" \
+     "\n        -o      Create" \
+        ) \
+        USE_FEATURE_CPIO_P( \
+     "\n        -p      Passthrough" \
+        ) \
+     "\nOptions:" \
+     "\n        -d      Make leading directories" \
+     "\n        -m      Preserve mtime" \
+     "\n        -v      Verbose" \
+     "\n        -u      Overwrite" \
+     "\n        -F      Input file" \
+        USE_FEATURE_CPIO_O( \
+     "\n        -H      Define format" \
         ) \
-     "\n        t       List" \
-     "\n        v       Verbose" \
-     "\n        u       Unconditional overwrite" \
-     "\n        F       Input from file" \
 
 #define crond_trivial_usage \
        "-fbS -l N " USE_FEATURE_CROND_D("-d N ") "-L LOGFILE -c DIR"
@@ -1167,6 +1172,7 @@
         USE_FEATURE_FIND_MAXDEPTH( \
      "\n        -maxdepth N     Descend at most N levels. -maxdepth 0 applies" \
      "\n                        tests/actions to command line arguments only") \
+     "\n        -mindepth N     Do not act on first N levels" \
      "\n        -name PATTERN   File name (w/o directory name) matches PATTERN" \
      "\n        -iname PATTERN  Case insensitive -name" \
         USE_FEATURE_FIND_PATH( \
@@ -1425,6 +1431,7 @@
        "eF" \
         USE_FEATURE_GREP_EGREP_ALIAS("E") \
         USE_FEATURE_GREP_CONTEXT("ABC") \
+        USE_EXTRA_COMPAT("z") \
        "] PATTERN [FILEs...]"
 #define grep_full_usage "\n\n" \
        "Search for PATTERN in each FILE or standard input\n" \
@@ -1453,6 +1460,8 @@
      "\n        -A      Print NUM lines of trailing context" \
      "\n        -B      Print NUM lines of leading context" \
      "\n        -C      Print NUM lines of output context") \
+        USE_EXTRA_COMPAT( \
+     "\n        -z      Input is NUL terminated") \
 
 #define grep_example_usage \
        "$ grep root /etc/passwd\n" \
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 50dc3affe..f64239a96 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -251,35 +251,33 @@ void FAST_FUNC re_exec(char **argv)
         bb_perror_msg_and_die("exec %s", bb_busybox_exec_path);
 }
 
-void FAST_FUNC forkexit_or_rexec(char **argv)
+pid_t FAST_FUNC fork_or_rexec(char **argv)
 {
         pid_t pid;
         /* Maybe we are already re-execed and come here again? */
         if (re_execed)
-                return;
+                return 0; /* child */
 
         pid = vfork();
         if (pid < 0) /* wtf? */
                 bb_perror_msg_and_die("vfork");
         if (pid) /* parent */
-                exit(EXIT_SUCCESS);
+                return pid;
         /* child - re-exec ourself */
         re_exec(argv);
 }
 #else
 /* Dance around (void)...*/
-#undef forkexit_or_rexec
-void FAST_FUNC forkexit_or_rexec(void)
+#undef fork_or_rexec
+pid_t FAST_FUNC fork_or_rexec(void)
 {
         pid_t pid;
         pid = fork();
         if (pid < 0) /* wtf? */
                 bb_perror_msg_and_die("fork");
-        if (pid) /* parent */
-                exit(EXIT_SUCCESS);
-        /* child */
+        return pid;
 }
-#define forkexit_or_rexec(argv) forkexit_or_rexec()
+#define fork_or_rexec(argv) fork_or_rexec()
 #endif
 
 /* Due to a #define in libbb.h on MMU systems we actually have 1 argument -
@@ -310,7 +308,8 @@ void FAST_FUNC bb_daemonize_or_rexec(int flags, char **argv)
                 fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
 
         if (!(flags & DAEMON_ONLY_SANITIZE)) {
-                forkexit_or_rexec(argv);
+                if (fork_or_rexec(argv))
+                        exit(EXIT_SUCCESS); /* parent */
                 /* if daemonizing, make sure we detach from stdio & ctty */
                 setsid();
                 dup2(fd, 0);
diff --git a/miscutils/setsid.c b/miscutils/setsid.c
index 127adf6f2..d7de1f149 100644
--- a/miscutils/setsid.c
+++ b/miscutils/setsid.c
@@ -26,7 +26,8 @@ int setsid_main(int argc UNUSED_PARAM, char **argv)
          * Otherwise our PID serves as PGID of some existing process group
          * and cannot be used as PGID of a new process group. */
         if (getpgrp() == getpid())
-                forkexit_or_rexec(argv);
+                if (fork_or_rexec(argv))
+                        exit(EXIT_SUCCESS); /* parent */
 
         setsid();  /* no error possible */
 
diff --git a/scripts/defconfig b/scripts/defconfig
index 6bf1a4a28..166989bba 100644
--- a/scripts/defconfig
+++ b/scripts/defconfig
@@ -112,6 +112,7 @@ CONFIG_BUNZIP2=y
 CONFIG_BZIP2=y
 CONFIG_CPIO=y
 CONFIG_FEATURE_CPIO_O=y
+CONFIG_FEATURE_CPIO_P=y
 # CONFIG_DPKG is not set
 # CONFIG_DPKG_DEB is not set
 # CONFIG_FEATURE_DPKG_DEB_EXTRACT_ONLY is not set