9 files changed, 254 insertions, 96 deletions

diff --git a/libbb/Kbuild.src b/libbb/Kbuild.src
index e0898565a..0e14e351e 100644
--- a/libbb/Kbuild.src
+++ b/libbb/Kbuild.src
@@ -43,7 +43,7 @@ lib-y += getopt32.o
 lib-y += get_volsize.o
 lib-y += herror_msg.o
 lib-y += human_readable.o
-lib-y += info_msg.o
+lib-y += inet_common.o
 lib-y += inode_hash.o
 lib-y += isdirectory.o
 lib-y += last_char_is.o
diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index 1d6a4b274..b71f2dd7e 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -140,32 +140,127 @@ void FAST_FUNC bb_show_usage(void)
         xfunc_die();
 }
 
-#if NUM_APPLETS > 8
-static int applet_name_compare(const void *name, const void *idx)
-{
-        int i = (int)(ptrdiff_t)idx - 1;
-        return strcmp(name, APPLET_NAME(i));
-}
-#endif
 int FAST_FUNC find_applet_by_name(const char *name)
 {
-#if NUM_APPLETS > 8
-        /* Do a binary search to find the applet entry given the name. */
+        unsigned i, max;
+        int j;
         const char *p;
-        p = bsearch(name, (void*)(ptrdiff_t)1, ARRAY_SIZE(applet_main), 1, applet_name_compare);
-        /*
-         * if (!p) return -1;
-         * ^^^^^^^^^^^^^^^^^^ the code below will do this if p == NULL :)
-         */
-        return (int)(ptrdiff_t)p - 1;
+
+/* The commented-out word-at-a-time code is ~40% faster, but +160 bytes.
+ * "Faster" here saves ~0.5 microsecond of real time - not worth it.
+ */
+#if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
+        uint32_t n32;
+
+        /* Handle all names < 2 chars long early */
+        if (name[0] == '\0')
+                return -1; /* "" is not a valid applet name */
+        if (name[1] == '\0') {
+                if (!ENABLE_TEST)
+                        return -1; /* 1-char name is not valid */
+                if (name[0] != ']')
+                        return -1; /* 1-char name which isn't "[" is not valid */
+                /* applet "[" is always applet #0: */
+                return 0;
+        }
+#endif
+
+        p = applet_names;
+        i = 0;
+#if KNOWN_APPNAME_OFFSETS <= 0
+        max = NUM_APPLETS;
 #else
-        /* A version which does not pull in bsearch */
-        int i = 0;
-        const char *p = applet_names;
-        while (i < NUM_APPLETS) {
-                if (strcmp(name, p) == 0)
+        max = NUM_APPLETS * KNOWN_APPNAME_OFFSETS;
+        for (j = ARRAY_SIZE(applet_nameofs)-1; j >= 0; j--) {
+                const char *pp = applet_names + applet_nameofs[j];
+                if (strcmp(name, pp) >= 0) {
+                        //bb_error_msg("name:'%s' >= pp:'%s'", name, pp);
+                        p = pp;
+                        i = max - NUM_APPLETS;
+                        break;
+                }
+                max -= NUM_APPLETS;
+        }
+        max /= (unsigned)KNOWN_APPNAME_OFFSETS;
+        i /= (unsigned)KNOWN_APPNAME_OFFSETS;
+        //bb_error_msg("name:'%s' starting from:'%s' i:%u max:%u", name, p, i, max);
+#endif
+
+        /* Open-coded linear search without strcmp/strlen calls for speed */
+
+#if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
+        /* skip "[\0" name, it's surely not it */
+        if (ENABLE_TEST && LONE_CHAR(p, '['))
+                i++, p += 2;
+        /* All remaining applet names in p[] are at least 2 chars long */
+        /* name[] is also at least 2 chars long */
+
+        n32 = (name[0] << 0) | (name[1] << 8) | (name[2] << 16);
+        while (i < max) {
+                uint32_t p32;
+                char ch;
+
+                /* Quickly check match of the first 3 bytes */
+                move_from_unaligned32(p32, p);
+                p += 3;
+                if ((p32 & 0x00ffffff) != n32) {
+                        /* Most likely case: 3 first bytes do not match */
+                        i++;
+                        if ((p32 & 0x00ff0000) == '\0')
+                                continue; // p[2] was NUL
+                        p++;
+                        if ((p32 & 0xff000000) == '\0')
+                                continue; // p[3] was NUL
+                        /* p[0..3] aren't matching and none is NUL, check the rest */
+                        while (*p++ != '\0')
+                                continue;
+                        continue;
+                }
+
+                /* Unlikely branch: first 3 bytes ([0..2]) match */
+                if ((p32 & 0x00ff0000) == '\0') {
+                        /* name is 2-byte long, it is full match */
+                        //bb_error_msg("found:'%s' i:%u", name, i);
                         return i;
-                p += strlen(p) + 1;
+                }
+                /* Check remaining bytes [3..NUL] */
+                ch = (p32 >> 24);
+                j = 3;
+                while (ch == name[j]) {
+                        if (ch == '\0') {
+                                //bb_error_msg("found:'%s' i:%u", name, i);
+                                return i;
+                        }
+                        ch = *++p;
+                        j++;
+                }
+                /* Not a match. Skip it, including NUL */
+                while (ch != '\0')
+                        ch = *++p;
+                p++;
+                i++;
+        }
+        return -1;
+#else
+        while (i < max) {
+                char ch;
+                j = 0;
+                /* Do we see "name\0" in applet_names[p] position? */
+                while ((ch = *p) == name[j]) {
+                        if (ch == '\0') {
+                                //bb_error_msg("found:'%s' i:%u", name, i);
+                                return i; /* yes */
+                        }
+                        p++;
+                        j++;
+                }
+                /* No.
+                 * p => 1st non-matching char in applet_names[],
+                 * skip to and including NUL.
+                 */
+                while (ch != '\0')
+                        ch = *++p;
+                p++;
                 i++;
         }
         return -1;
@@ -588,6 +683,7 @@ static void install_links(const char *busybox, int use_symbolic_links,
          * busybox.h::bb_install_loc_t, or else... */
         int (*lf)(const char *, const char *);
         char *fpc;
+        const char *appname = applet_names;
         unsigned i;
         int rc;
 
@@ -598,7 +694,7 @@ static void install_links(const char *busybox, int use_symbolic_links,
         for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
                 fpc = concat_path_file(
                                 custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
-                                APPLET_NAME(i));
+                                appname);
                 // debug: bb_error_msg("%slinking %s to busybox",
                 //              use_symbolic_links ? "sym" : "", fpc);
                 rc = lf(busybox, fpc);
@@ -606,6 +702,8 @@ static void install_links(const char *busybox, int use_symbolic_links,
                         bb_simple_perror_msg(fpc);
                 }
                 free(fpc);
+                while (*appname++ != '\0')
+                        continue;
         }
 }
 # else
@@ -769,7 +867,7 @@ void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
 
         /* Reinit some shared global data */
         xfunc_error_retval = EXIT_FAILURE;
-        applet_name = APPLET_NAME(applet_no);
+        applet_name = bb_get_last_path_component_nostrip(argv[0]);
 
         /* Special case. POSIX says "test --help"
          * should be no different from e.g. "test --foo".
@@ -800,11 +898,14 @@ void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
 
 void FAST_FUNC 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);
+        int applet;
+
         if (is_prefixed_with(name, "busybox"))
                 exit(busybox_main(argv));
+        /* find_applet_by_name() search is more expensive, so goes second */
+        applet = find_applet_by_name(name);
+        if (applet >= 0)
+                run_applet_no_and_exit(applet, argv);
 }
 
 #endif /* !defined(SINGLE_APPLET_MAIN) */
@@ -817,6 +918,19 @@ int lbb_main(char **argv)
 int main(int argc UNUSED_PARAM, char **argv)
 #endif
 {
+#if 0
+        /* TODO: find a use for a block of memory between end of .bss
+         * and end of page. For example, I'm getting "_end:0x812e698 2408 bytes"
+         * - more than 2k of wasted memory (in this particular build)
+         * *per each running process*!
+         * (If your linker does not generate "_end" name, weak attribute
+         * makes &_end == NULL, end_len == 0 here.)
+         */
+        extern char _end[] __attribute__((weak));
+        unsigned end_len = (-(int)_end) & 0xfff;
+        printf("_end:%p %u bytes\n", &_end, end_len);
+#endif
+
         /* Tweak malloc for reduced memory consumption */
 #ifdef M_TRIM_THRESHOLD
         /* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
diff --git a/libbb/executable.c b/libbb/executable.c
index 12a48cea3..308c525a3 100644
--- a/libbb/executable.c
+++ b/libbb/executable.c
@@ -97,10 +97,19 @@ int FAST_FUNC BB_EXECVP(const char *file, char *const argv[])
 }
 #endif
 
-int FAST_FUNC BB_EXECVP_or_die(char **argv)
+void FAST_FUNC BB_EXECVP_or_die(char **argv)
 {
         BB_EXECVP(argv[0], argv);
         /* SUSv3-mandated exit codes */
         xfunc_error_retval = (errno == ENOENT) ? 127 : 126;
         bb_perror_msg_and_die("can't execute '%s'", argv[0]);
 }
+
+/* Typical idiom for applets which exec *optional* PROG [ARGS] */
+void FAST_FUNC exec_prog_or_SHELL(char **argv)
+{
+        if (argv[0]) {
+                BB_EXECVP_or_die(argv);
+        }
+        run_shell(getenv("SHELL"), /*login:*/ 1, NULL, NULL);
+}
diff --git a/libbb/info_msg.c b/libbb/info_msg.c
deleted file mode 100644
index 56ca2efd4..000000000
--- a/libbb/info_msg.c
+++ /dev/null
@@ -1,62 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * Utility routines.
- *
- * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
- *
- * Licensed under GPLv2 or later, see file LICENSE in this source tree.
- */
-
-#include "libbb.h"
-#if ENABLE_FEATURE_SYSLOG
-# include <syslog.h>
-#endif
-
-void FAST_FUNC bb_info_msg(const char *s, ...)
-{
-#ifdef THIS_ONE_DOESNT_DO_SINGLE_WRITE
-        va_list p;
-        /* va_copy is used because it is not portable
-         * to use va_list p twice */
-        va_list p2;
-
-        va_start(p, s);
-        va_copy(p2, p);
-        if (logmode & LOGMODE_STDIO) {
-                vprintf(s, p);
-                fputs(msg_eol, stdout);
-        }
-# if ENABLE_FEATURE_SYSLOG
-        if (logmode & LOGMODE_SYSLOG)
-                vsyslog(LOG_INFO, s, p2);
-# endif
-        va_end(p2);
-        va_end(p);
-#else
-        int used;
-        char *msg;
-        va_list p;
-
-        if (logmode == 0)
-                return;
-
-        va_start(p, s);
-        used = vasprintf(&msg, s, p);
-        va_end(p);
-        if (used < 0)
-                return;
-
-# if ENABLE_FEATURE_SYSLOG
-        if (logmode & LOGMODE_SYSLOG)
-                syslog(LOG_INFO, "%s", msg);
-# endif
-        if (logmode & LOGMODE_STDIO) {
-                fflush_all();
-                /* used = strlen(msg); - must be true already */
-                msg[used++] = '\n';
-                full_write(STDOUT_FILENO, msg, used);
-        }
-
-        free(msg);
-#endif
-}
diff --git a/libbb/ubi.c b/libbb/ubi.c
new file mode 100644
index 000000000..34595d797
--- /dev/null
+++ b/libbb/ubi.c
@@ -0,0 +1,43 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2016 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+//kbuild:lib-y += ubi.o
+
+#include "libbb.h"
+
+// from ubi-media.h
+#define UBI_MAX_VOLUME_NAME 127
+#define UBI_MAX_VOLUMES     128
+
+unsigned FAST_FUNC ubi_devnum_from_devname(const char *str)
+{
+        unsigned ubi_devnum;
+
+        if (sscanf(str, "/dev/ubi%u", &ubi_devnum) != 1)
+                bb_error_msg_and_die("not an UBI device: '%s'", str);
+        return ubi_devnum;
+}
+
+int FAST_FUNC ubi_get_volid_by_name(unsigned ubi_devnum, const char *vol_name)
+{
+        unsigned i;
+
+        for (i = 0; i < UBI_MAX_VOLUMES; i++) {
+                char buf[UBI_MAX_VOLUME_NAME + 1];
+                char fname[sizeof("/sys/class/ubi/ubi%u_%u/name") + 2 * sizeof(int)*3];
+
+                sprintf(fname, "/sys/class/ubi/ubi%u_%u/name", ubi_devnum, i);
+                if (open_read_close(fname, buf, sizeof(buf)) <= 0)
+                        continue;
+
+                strchrnul(buf, '\n')[0] = '\0';
+                if (strcmp(vol_name, buf) == 0)
+                        return i;
+        }
+        bb_error_msg_and_die("volume '%s' not found", vol_name);
+}
diff --git a/libbb/verror_msg.c b/libbb/verror_msg.c
index 0ef2a311f..22c30357b 100644
--- a/libbb/verror_msg.c
+++ b/libbb/verror_msg.c
@@ -20,6 +20,7 @@ const char *msg_eol = "\n";
 void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
 {
         char *msg, *msg1;
+        char stack_msg[80];
         int applet_len, strerr_len, msgeol_len, used;
 
         if (!logmode)
@@ -28,6 +29,27 @@ void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
         if (!s) /* nomsg[_and_die] uses NULL fmt */
                 s = ""; /* some libc don't like printf(NULL) */
 
+        applet_len = strlen(applet_name) + 2; /* "applet: " */
+        strerr_len = strerr ? strlen(strerr) : 0;
+        msgeol_len = strlen(msg_eol);
+
+        /* This costs ~90 bytes of code, but avoids costly
+         * malloc()[in vasprintf]+realloc()+memmove()+free() in 99% of cases.
+         * ~40% speedup.
+         */
+        if ((int)sizeof(stack_msg) - applet_len > 0) {
+                va_list p2;
+
+                /* It is not portable to use va_list twice, need to va_copy it */
+                va_copy(p2, p);
+                used = vsnprintf(stack_msg + applet_len, (int)sizeof(stack_msg) - applet_len, s, p2);
+                va_end(p2);
+                msg = stack_msg;
+                used += applet_len;
+                if (used < (int)sizeof(stack_msg) - 3 - msgeol_len - strerr_len)
+                        goto add_pfx_and_sfx;
+        }
+
         used = vasprintf(&msg, s, p);
         if (used < 0)
                 return;
@@ -37,9 +59,6 @@ void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
          * This is needed for e.g. httpd logging, when multiple
          * children can produce log messages simultaneously. */
 
-        applet_len = strlen(applet_name) + 2; /* "applet: " */
-        strerr_len = strerr ? strlen(strerr) : 0;
-        msgeol_len = strlen(msg_eol);
         /* can't use xrealloc: it calls error_msg on failure,
          * that may result in a recursion */
         /* +3 is for ": " before strerr and for terminating NUL */
@@ -52,6 +71,7 @@ void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
                 /* TODO: maybe use writev instead of memmoving? Need full_writev? */
                 memmove(msg + applet_len, msg, used);
                 used += applet_len;
+ add_pfx_and_sfx:
                 strcpy(msg, applet_name);
                 msg[applet_len - 2] = ':';
                 msg[applet_len - 1] = ' ';
@@ -76,7 +96,8 @@ void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
                 syslog(syslog_level, "%s", msg + applet_len);
         }
 #endif
-        free(msg);
+        if (msg != stack_msg)
+                free(msg);
 }
 
 #ifdef VERSION_WITH_WRITEV
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 2d3204507..f488f8e0c 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -118,8 +118,6 @@ int FAST_FUNC run_nofork_applet(int applet_no, char **argv)
 
         save_nofork_data(&old);
 
-        applet_name = APPLET_NAME(applet_no);
-
         xfunc_error_retval = EXIT_FAILURE;
 
         /* In case getopt() or getopt32() was already called:
@@ -159,6 +157,7 @@ int FAST_FUNC run_nofork_applet(int applet_no, char **argv)
                  * need argv untouched because they free argv[i]! */
                 char *tmp_argv[argc+1];
                 memcpy(tmp_argv, argv, (argc+1) * sizeof(tmp_argv[0]));
+                applet_name = tmp_argv[0];
                 /* Finally we can call NOFORK applet's main() */
                 rc = applet_main[applet_no](argc, tmp_argv);
         } else {
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index 206edb4a0..3f9a84ad4 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -315,3 +315,15 @@ int FAST_FUNC wait4pid(pid_t pid)
                 return WTERMSIG(status) + 0x180;
         return 0;
 }
+
+// Useful when we do know that pid is valid, and we just want to wait
+// for it to exit. Not existing pid is fatal. waitpid() status is not returned.
+int FAST_FUNC wait_for_exitstatus(pid_t pid)
+{
+        int exit_status, n;
+
+        n = safe_waitpid(pid, &exit_status, 0);
+        if (n < 0)
+                bb_perror_msg_and_die("waitpid");
+        return exit_status;
+}
diff --git a/libbb/xfuncs_printf.c b/libbb/xfuncs_printf.c
index 73488908d..e9222f690 100644
--- a/libbb/xfuncs_printf.c
+++ b/libbb/xfuncs_printf.c
@@ -390,6 +390,12 @@ void FAST_FUNC xchdir(const char *path)
                 bb_perror_msg_and_die("can't change directory to '%s'", path);
 }
 
+void FAST_FUNC xfchdir(int fd)
+{
+        if (fchdir(fd))
+                bb_perror_msg_and_die("fchdir");
+}
+
 void FAST_FUNC xchroot(const char *path)
 {
         if (chroot(path))
@@ -653,3 +659,19 @@ pid_t FAST_FUNC xfork(void)
         return pid;
 }
 #endif
+
+void FAST_FUNC xvfork_parent_waits_and_exits(void)
+{
+        pid_t pid;
+
+        fflush_all();
+        pid = xvfork();
+        if (pid > 0) {
+                /* Parent */
+                int exit_status = wait_for_exitstatus(pid);
+                if (WIFSIGNALED(exit_status))
+                        kill_myself_with_sig(WTERMSIG(exit_status));
+                _exit(WEXITSTATUS(exit_status));
+        }
+        /* Child continues */
+}