Merge branch 'busybox' into merge

12 files changed, 156 insertions, 82 deletions

diff --git a/libbb/Config.src b/libbb/Config.src
index c51640305..16c79dbf0 100644
--- a/libbb/Config.src
+++ b/libbb/Config.src
@@ -3,7 +3,7 @@
 # see scripts/kbuild/config-language.txt.
 #
 
-menu "Busybox Library Tuning"
+comment "Library Tuning"
 
 INSERT
 
@@ -66,7 +66,7 @@ config FEATURE_FAST_TOP
         bool "Faster /proc scanning code (+100 bytes)"
         default n  # all "fast or small" options default to small
         help
-          This option makes top (and ps) ~20% faster (or 20% less CPU hungry),
+          This option makes top and ps ~20% faster (or 20% less CPU hungry),
           but code size is slightly bigger.
 
 config FEATURE_ETC_NETWORKS
@@ -302,13 +302,17 @@ config FEATURE_VERBOSE_CP_MESSAGE
         default n
         help
           Error messages with this feature enabled:
+
             $ cp file /does_not_exist/file
             cp: cannot create '/does_not_exist/file': Path does not exist
             $ cp file /vmlinuz/file
             cp: cannot stat '/vmlinuz/file': Path has non-directory component
+
           If this feature is not enabled, they will be, respectively:
+
             cp: cannot create '/does_not_exist/file': No such file or directory
             cp: cannot stat '/vmlinuz/file': Not a directory
+
           This will cost you ~60 bytes.
 
 config FEATURE_USE_SENDFILE
@@ -376,7 +380,4 @@ config FEATURE_HWIB
         bool "Support infiniband HW"
         default y
         help
-          Support for printing infiniband addresses in
-          network applets.
-
-endmenu
+          Support for printing infiniband addresses in network applets.
diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index a31a73e90..34b73afa5 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -78,6 +78,17 @@
 #endif
 
 
+unsigned FAST_FUNC string_array_len(char **argv)
+{
+        char **start = argv;
+
+        while (*argv)
+                argv++;
+
+        return argv - start;
+}
+
+
 #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
 static const char usage_messages[] ALIGN1 = UNPACKED_USAGE;
 #else
@@ -675,8 +686,21 @@ static void check_suid(int applet_no)
                 if (geteuid())
                         bb_error_msg_and_die("must be suid to work properly");
         } else if (APPLET_SUID(applet_no) == BB_SUID_DROP) {
-                xsetgid(rgid);  /* drop all privileges */
-                xsetuid(ruid);
+                /*
+                 * Drop all privileges.
+                 *
+                 * Don't check for errors: in normal use, they are impossible,
+                 * and in special cases, exiting is harmful. Example:
+                 * 'unshare --user' when user's shell is also from busybox.
+                 *
+                 * 'unshare --user' creates a new user namespace without any
+                 * uid mappings. Thus, busybox binary is setuid nobody:nogroup
+                 * within the namespace, as that is the only user. However,
+                 * since no uids are mapped, calls to setgid/setuid
+                 * fail (even though they would do nothing).
+                 */
+                setgid(rgid);
+                setuid(ruid);
         }
 #  if ENABLE_FEATURE_SUID_CONFIG
  ret: ;
@@ -919,16 +943,17 @@ static int busybox_main(char **argv)
 # endif
 
 # if NUM_APPLETS > 0
-void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
+void FAST_FUNC run_applet_no_and_exit(int applet_no, const char *name, char **argv)
 {
-        int argc = 1;
-
-        while (argv[argc])
-                argc++;
+        int argc = string_array_len(argv);
 
         /* Reinit some shared global data */
         xfunc_error_retval = EXIT_FAILURE;
-        applet_name = bb_get_last_path_component_nostrip(argv[0]);
+        /*
+         * We do not use argv[0]: do not want to repeat massaging of
+         * "-/sbin/halt" -> "halt", for example.
+         */
+        applet_name = name;
 
         /* Special case. POSIX says "test --help"
          * should be no different from e.g. "test --foo".
@@ -972,7 +997,7 @@ static NORETURN void run_applet_and_exit(const char *name, char **argv)
         {
                 int applet = find_applet_by_name(name);
                 if (applet >= 0)
-                        run_applet_no_and_exit(applet, argv);
+                        run_applet_no_and_exit(applet, name, argv);
         }
 #  endif
 
@@ -1058,7 +1083,11 @@ int main(int argc UNUSED_PARAM, char **argv)
         }
         /* applet_names in this case is just "applet\0\0" */
         lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
+# if ENABLE_BUILD_LIBBUSYBOX
+        return SINGLE_APPLET_MAIN(string_array_len(argv), argv);
+# else
         return SINGLE_APPLET_MAIN(argc, argv);
+# endif
 
 #elif !ENABLE_BUSYBOX && NUM_APPLETS == 0
 
diff --git a/libbb/bb_getgroups.c b/libbb/bb_getgroups.c
new file mode 100644
index 000000000..59ae53738
--- /dev/null
+++ b/libbb/bb_getgroups.c
@@ -0,0 +1,47 @@
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2017 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+
+//kbuild:lib-y += bb_getgroups.o
+
+#include "libbb.h"
+
+gid_t* FAST_FUNC bb_getgroups(int *ngroups, gid_t *group_array)
+{
+        int n = ngroups ? *ngroups : 0;
+
+        /* getgroups may be a bit expensive, try to use it only once */
+        if (n < 32)
+                n = 32;
+
+        for (;;) {
+// FIXME: ash tries so hard to not die on OOM (when we are called from test),
+// and we spoil it with just one xrealloc here
+                group_array = xrealloc(group_array, (n+1) * sizeof(group_array[0]));
+                n = getgroups(n, group_array);
+                /*
+                 * If buffer is too small, kernel does not return new_n > n.
+                 * It returns -1 and EINVAL:
+                 */
+                if (n >= 0) {
+                        /* Terminator for bb_getgroups(NULL, NULL) usage */
+                        group_array[n] = (gid_t) -1;
+                        break;
+                }
+                if (errno == EINVAL) { /* too small? */
+                        /* This is the way to ask kernel how big the array is */
+                        n = getgroups(0, group_array);
+                        continue;
+                }
+                /* Some other error (should never happen on Linux) */
+                bb_perror_msg_and_die("getgroups");
+        }
+
+        if (ngroups)
+                *ngroups = n;
+        return group_array;
+}
diff --git a/libbb/common_bufsiz.c b/libbb/common_bufsiz.c
index 2847eb57d..f1124ba0e 100644
--- a/libbb/common_bufsiz.c
+++ b/libbb/common_bufsiz.c
@@ -19,6 +19,7 @@
 //config:
 //config:         At link time, "text" is padded to a full page. At runtime, all "text"
 //config:         pages are mapped RO and executable.
+//config:
 //config:         "Data" starts on the next page boundary, but is not padded
 //config:         to a full page at the end. "Bss" starts wherever "data" ends.
 //config:         At runtime, "data" pages are mapped RW and they are file-backed
diff --git a/libbb/copyfd.c b/libbb/copyfd.c
index 7e3531903..921fe3f81 100644
--- a/libbb/copyfd.c
+++ b/libbb/copyfd.c
@@ -119,8 +119,11 @@ static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
         }
  out:
 
+/* some environments don't have munmap(), hide it in #if */
+#if CONFIG_FEATURE_COPYBUF_KB > 4
         if (buffer_size > 4 * 1024)
                 munmap(buffer, buffer_size);
+#endif
         return status ? -1 : total;
 }
 
diff --git a/libbb/dump.c b/libbb/dump.c
index 87c1dce13..211a1ed9e 100644
--- a/libbb/dump.c
+++ b/libbb/dump.c
@@ -58,7 +58,7 @@ static NOINLINE int bb_dump_size(FS *fs)
         const char *p;
         int prec;
 
-        /* figure out the data block bb_dump_size needed for each format unit */
+        /* figure out the data block size needed for each format unit */
         for (cur_size = 0, fu = fs->nextfu; fu; fu = fu->nextfu) {
                 if (fu->bcnt) {
                         cur_size += fu->bcnt * fu->reps;
@@ -311,20 +311,18 @@ static NOINLINE void rewrite(priv_dumper_t *dumper, FS *fs)
         }
 }
 
-static void do_skip(priv_dumper_t *dumper, const char *fname, int statok)
+static void do_skip(priv_dumper_t *dumper, const char *fname)
 {
         struct stat sbuf;
 
-        if (statok) {
-                xfstat(STDIN_FILENO, &sbuf, fname);
-                if (!(S_ISCHR(sbuf.st_mode) || S_ISBLK(sbuf.st_mode) || S_ISFIFO(sbuf.st_mode))
-                 && dumper->pub.dump_skip >= sbuf.st_size
-                ) {
-                        /* If bb_dump_size valid and pub.dump_skip >= size */
-                        dumper->pub.dump_skip -= sbuf.st_size;
-                        dumper->address += sbuf.st_size;
-                        return;
-                }
+        xfstat(STDIN_FILENO, &sbuf, fname);
+        if (S_ISREG(sbuf.st_mode)
+         && dumper->pub.dump_skip >= sbuf.st_size
+        ) {
+                /* If st_size is valid and pub.dump_skip >= st_size */
+                dumper->pub.dump_skip -= sbuf.st_size;
+                dumper->address += sbuf.st_size;
+                return;
         }
         if (fseeko(stdin, dumper->pub.dump_skip, SEEK_SET)) {
                 bb_simple_perror_msg_and_die(fname);
@@ -336,29 +334,26 @@ static void do_skip(priv_dumper_t *dumper, const char *fname, int statok)
 
 static NOINLINE int next(priv_dumper_t *dumper)
 {
-        int statok;
-
         for (;;) {
-                if (*dumper->argv) {
-                        dumper->next__done = statok = 1;
-                        if (!(freopen(*dumper->argv, "r", stdin))) {
-                                bb_simple_perror_msg(*dumper->argv);
-                                dumper->exitval = 1;
-                                ++dumper->argv;
-                                continue;
+                const char *fname = *dumper->argv;
+
+                if (fname) {
+                        dumper->argv++;
+                        if (NOT_LONE_DASH(fname)) {
+                                if (!freopen(fname, "r", stdin)) {
+                                        bb_simple_perror_msg(fname);
+                                        dumper->exitval = 1;
+                                        continue;
+                                }
                         }
                 } else {
                         if (dumper->next__done)
                                 return 0; /* no next file */
-                        dumper->next__done = 1;
-//why stat of stdin is specially prohibited?
-                        statok = 0;
                 }
+                dumper->next__done = 1;
                 if (dumper->pub.dump_skip)
-                        do_skip(dumper, statok ? *dumper->argv : "stdin", statok);
-                if (*dumper->argv)
-                        ++dumper->argv;
-                if (!dumper->pub.dump_skip)
+                        do_skip(dumper, fname ? fname : "stdin");
+                if (dumper->pub.dump_skip == 0)
                         return 1;
         }
         /* NOTREACHED */
@@ -670,7 +665,7 @@ int FAST_FUNC bb_dump_dump(dumper_t *pub_dumper, char **argv)
         FS *tfs;
         int blocksize;
 
-        /* figure out the data block bb_dump_size */
+        /* figure out the data block size */
         blocksize = 0;
         tfs = dumper->pub.fshead;
         while (tfs) {
diff --git a/libbb/getopt32.c b/libbb/getopt32.c
index b87b83538..80f4cc060 100644
--- a/libbb/getopt32.c
+++ b/libbb/getopt32.c
@@ -379,9 +379,7 @@ getopt32(char **argv, const char *applet_opts, ...)
         int spec_flgs = 0;
 
         /* skip 0: some applets cheat: they do not actually HAVE argv[0] */
-        argc = 1;
-        while (argv[argc])
-                argc++;
+        argc = 1 + string_array_len(argv + 1);
 
         va_start(p, applet_opts);
 
diff --git a/libbb/inet_common.c b/libbb/inet_common.c
index 5b4a4a10b..04259f47b 100644
--- a/libbb/inet_common.c
+++ b/libbb/inet_common.c
@@ -11,6 +11,12 @@
 #include "libbb.h"
 #include "inet_common.h"
 
+#if 0
+# define dbg(...) bb_error_msg(__VA_ARGS__)
+#else
+# define dbg(...) ((void)0)
+#endif
+
 int FAST_FUNC INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst)
 {
         struct hostent *hp;
@@ -33,9 +39,7 @@ int FAST_FUNC INET_resolve(const char *name, struct sockaddr_in *s_in, int hostf
         }
         /* If we expect this to be a hostname, try hostname database first */
         if (hostfirst) {
-#ifdef DEBUG
-                bb_error_msg("gethostbyname(%s)", name);
-#endif
+                dbg("gethostbyname(%s)", name);
                 hp = gethostbyname(name);
                 if (hp) {
                         memcpy(&s_in->sin_addr, hp->h_addr_list[0],
@@ -45,9 +49,7 @@ int FAST_FUNC INET_resolve(const char *name, struct sockaddr_in *s_in, int hostf
         }
 #if ENABLE_FEATURE_ETC_NETWORKS
         /* Try the NETWORKS database to see if this is a known network. */
-#ifdef DEBUG
-        bb_error_msg("getnetbyname(%s)", name);
-#endif
+        dbg("getnetbyname(%s)", name);
         np = getnetbyname(name);
         if (np) {
                 s_in->sin_addr.s_addr = htonl(np->n_net);
@@ -61,8 +63,8 @@ int FAST_FUNC INET_resolve(const char *name, struct sockaddr_in *s_in, int hostf
 #ifdef DEBUG
         res_init();
         _res.options |= RES_DEBUG;
-        bb_error_msg("gethostbyname(%s)", name);
 #endif
+        dbg("gethostbyname(%s)", name);
         hp = gethostbyname(name);
         if (!hp) {
                 return -1;
@@ -93,17 +95,12 @@ char* FAST_FUNC INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t ne
         smallint is_host;
 
         if (s_in->sin_family != AF_INET) {
-#ifdef DEBUG
-                bb_error_msg("rresolve: unsupported address family %d!",
-                                s_in->sin_family);
-#endif
+                dbg("rresolve: unsupported address family %d!", s_in->sin_family);
                 errno = EAFNOSUPPORT;
                 return NULL;
         }
         nip = s_in->sin_addr.s_addr;
-#ifdef DEBUG
-        bb_error_msg("rresolve: %08x mask:%08x num:%08x", (unsigned)nip, netmask, numeric);
-#endif
+        dbg("rresolve: %08x mask:%08x num:%08x", (unsigned)nip, netmask, numeric);
         if (numeric & 0x0FFF)
                 return xmalloc_sockaddr2dotted_noport((void*)s_in);
         if (nip == INADDR_ANY) {
@@ -117,10 +114,8 @@ char* FAST_FUNC INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t ne
         pn = cache;
         while (pn) {
                 if (pn->nip == nip && pn->is_host == is_host) {
-#ifdef DEBUG
-                        bb_error_msg("rresolve: found %s %08x in cache",
+                        dbg("rresolve: found %s %08x in cache",
                                 (is_host ? "host" : "net"), (unsigned)nip);
-#endif
                         return xstrdup(pn->name);
                 }
                 pn = pn->next;
@@ -128,19 +123,18 @@ char* FAST_FUNC INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t ne
 
         name = NULL;
         if (is_host) {
-#ifdef DEBUG
-                bb_error_msg("sockaddr2host_noport(%08x)", (unsigned)nip);
-#endif
+                dbg("sockaddr2host_noport(%08x)", (unsigned)nip);
                 name = xmalloc_sockaddr2host_noport((void*)s_in);
-        } else if (ENABLE_FEATURE_ETC_NETWORKS) {
+        }
+#if ENABLE_FEATURE_ETC_NETWORKS
+        else {
                 struct netent *np;
-#ifdef DEBUG
-                bb_error_msg("getnetbyaddr(%08x)", (unsigned)ntohl(nip));
-#endif
+                dbg("getnetbyaddr(%08x)", (unsigned)ntohl(nip));
                 np = getnetbyaddr(ntohl(nip), AF_INET);
                 if (np)
                         name = xstrdup(np->n_name);
         }
+#endif
         if (!name)
                 name = xmalloc_sockaddr2dotted_noport((void*)s_in);
 
@@ -183,10 +177,8 @@ int FAST_FUNC INET6_resolve(const char *name, struct sockaddr_in6 *sin6)
 char* FAST_FUNC INET6_rresolve(struct sockaddr_in6 *sin6, int numeric)
 {
         if (sin6->sin6_family != AF_INET6) {
-#ifdef DEBUG
-                bb_error_msg("rresolve: unsupported address family %d!",
+                dbg("rresolve: unsupported address family %d!",
                                 sin6->sin6_family);
-#endif
                 errno = EAFNOSUPPORT;
                 return NULL;
         }
diff --git a/libbb/messages.c b/libbb/messages.c
index d74c237e7..3c0b921cf 100644
--- a/libbb/messages.c
+++ b/libbb/messages.c
@@ -14,12 +14,10 @@
 
 /* allow version to be extended, via CFLAGS */
 #ifndef BB_EXTRA_VERSION
-#define BB_EXTRA_VERSION BB_BT
+#define BB_EXTRA_VERSION " ("AUTOCONF_TIMESTAMP")"
 #endif
 
-#define BANNER "BusyBox v" BB_VER " (" BB_EXTRA_VERSION ")"
-
-const char bb_banner[] ALIGN1 = BANNER;
+const char bb_banner[] ALIGN1 = "BusyBox v" BB_VER BB_EXTRA_VERSION;
 
 
 const char bb_msg_memory_exhausted[] ALIGN1 = "out of memory";
diff --git a/libbb/print_numbered_lines.c b/libbb/print_numbered_lines.c
index 702aed1ea..9a8a51440 100644
--- a/libbb/print_numbered_lines.c
+++ b/libbb/print_numbered_lines.c
@@ -24,6 +24,7 @@ void FAST_FUNC print_numbered_lines(struct number_state *ns, const char *filenam
                         fputs(ns->empty_str, stdout);
                 free(line);
         }
+        ns->start = N;
 
         fclose(fp);
 }
diff --git a/libbb/safe_write.c b/libbb/safe_write.c
index 8f7628016..aad50f5e0 100644
--- a/libbb/safe_write.c
+++ b/libbb/safe_write.c
@@ -13,9 +13,17 @@ ssize_t FAST_FUNC safe_write(int fd, const void *buf, size_t count)
 {
         ssize_t n;
 
-        do {
+        for (;;) {
                 n = write(fd, buf, count);
-        } while (n < 0 && errno == EINTR);
+                if (n >= 0 || errno != EINTR)
+                        break;
+                /* Some callers set errno=0, are upset when they see EINTR.
+                 * Returning EINTR is wrong since we retry write(),
+                 * the "error" was transient.
+                 */
+                errno = 0;
+                /* repeat the write() */
+        }
 
         return n;
 }
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 9ab49d0a1..4b3ed5a3b 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -16,6 +16,7 @@
  */
 
 #include "busybox.h" /* uses applet tables */
+#include "NUM_APPLETS.h"
 
 #if !ENABLE_PLATFORM_MINGW32
 /* This does a fork/exec in one call, using vfork().  Returns PID of new child,
@@ -158,7 +159,7 @@ int FAST_FUNC run_nofork_applet(int applet_no, char **argv)
 int FAST_FUNC spawn_and_wait(char **argv)
 {
         int rc;
-#if ENABLE_FEATURE_PREFER_APPLETS
+#if ENABLE_FEATURE_PREFER_APPLETS && (NUM_APPLETS > 1)
         int a = find_applet_by_name(argv[0]);
 
         if (a >= 0) {
@@ -182,7 +183,7 @@ int FAST_FUNC spawn_and_wait(char **argv)
                          * as of yet (and that should probably always stay true).
                          */
                         /* xfunc_error_retval and applet_name are init by: */
-                        run_applet_no_and_exit(a, argv);
+                        run_applet_no_and_exit(a, argv[0], argv);
                 }
 #  endif
 # endif