Changeset 3621 in MondoRescue for branches/3.3/mindi-busybox/libbb/appletlib.c

Timestamp:

Dec 20, 2016, 4:07:32 PM (7 years ago)

Author:

Bruno Cornec

Message:

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.

Location:

branches/3.3

Files:

• . (copied) (copied from branches/3.2 )
• mindi-busybox/libbb/appletlib.c (modified) (22 diffs)

branches/3.3/mindi-busybox/libbb/appletlib.c

@@ -30 +30 @@
 
 #if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
-        || defined(__APPLE__) \
+    || defined(__APPLE__) \
     )
 # include <malloc.h> /* for mallopt */
@@ -53 +53 @@
 #include "usage_compressed.h"
 
+static void run_applet_and_exit(const char *name, char **argv) NORETURN;
 
 #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
@@ -131 +132 @@
             full_write2_str(" ");
             full_write2_str(p);
-            full_write2_str("\n\n");
+            full_write2_str("\n");
         }
         if (ENABLE_FEATURE_CLEAN_UP)
@@ -140 +141 @@
 }
 
-#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++;
     }
@@ -185 +281 @@
     applet_name = applet;
 
-    /* Set locale for everybody except 'init' */
-    if (ENABLE_LOCALE_SUPPORT && getpid() != 1)
+    if (ENABLE_LOCALE_SUPPORT)
         setlocale(LC_ALL, "");
 
@@ -195 +290 @@
      && !argv[2]
      && strcmp(argv[1], "--help") == 0
-     && strncmp(applet, "busybox", 7) != 0
+     && !is_prefixed_with(applet, "busybox")
     ) {
         /* Special case. POSIX says "test --help"
@@ -439 +534 @@
                     }
                     *e = ':'; /* get_uidgid needs USER:GROUP syntax */
-                    if (get_uidgid(&sct->m_ugid, s, /*allow_numeric:*/ 1) == 0) {
+                    if (get_uidgid(&sct->m_ugid, s) == 0) {
                         errmsg = "unknown user/group";
                         goto pe_label;
@@ -459 +554 @@
             goto pe_label;
         }
-
     } /* while (1) */
 
@@ -586 +680 @@
     int (*lf)(const char *, const char *);
     char *fpc;
+        const char *appname = applet_names;
     unsigned i;
     int rc;
@@ -596 +691 @@
         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);
@@ -604 +699 @@
         }
         free(fpc);
-    }
-}
-# else
-#  define install_links(x,y,z) ((void)0)
+        while (*appname++ != '\0')
+            continue;
+    }
+}
+# elif ENABLE_BUSYBOX
+static void install_links(const char *busybox UNUSED_PARAM,
+        int use_symbolic_links UNUSED_PARAM,
+        char *custom_install_dir UNUSED_PARAM)
+{
+}
 # endif
 
+# if ENABLE_BUSYBOX
 /* If we were called as "busybox..." */
 static int busybox_main(char **argv)
@@ -622 +724 @@
         if (ENABLE_FEATURE_AUTOWIDTH) {
             /* Obtain the terminal width */
-            get_terminal_width_height(0, &output_width, NULL);
+            output_width = get_terminal_width(2);
         }
 
@@ -629 +731 @@
         full_write2_str(" multi-call binary.\n"); /* reuse */
         full_write2_str(
-            "BusyBox is copyrighted by many authors between 1998-2012.\n"
+            "BusyBox is copyrighted by many authors between 1998-2015.\n"
             "Licensed under GPLv2. See source distribution for detailed\n"
             "copyright notices.\n"
@@ -640 +742 @@
             "   or: function [arguments]...\n"
             "\n"
+            IF_NOT_FEATURE_SH_STANDALONE(
             "\tBusyBox is a multi-call binary that combines many common Unix\n"
             "\tutilities into a single executable.  Most people will create a\n"
             "\tlink to busybox for each function they wish to use and BusyBox\n"
             "\twill act like whatever it was invoked as.\n"
+            )
+            IF_FEATURE_SH_STANDALONE(
+            "\tBusyBox is a multi-call binary that combines many common Unix\n"
+            "\tutilities into a single executable.  The shell in this build\n"
+            "\tis configured to run built-in utilities without $PATH search.\n"
+            "\tYou don't need to install a link to busybox for each utility.\n"
+            "\tTo run external program, use full path (/sbin/ip instead of ip).\n"
+            )
             "\n"
             "Currently defined functions:\n"
@@ -671 +782 @@
     }
 
-    if (strncmp(argv[1], "--list", 6) == 0) {
+    if (is_prefixed_with(argv[1], "--list")) {
         unsigned i = 0;
         const char *a = applet_names;
         dup2(1, 2);
         while (*a) {
-# if ENABLE_FEATURE_INSTALLER
+#  if ENABLE_FEATURE_INSTALLER
             if (argv[1][6]) /* --list-full? */
                 full_write2_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
-# endif
+#  endif
             full_write2_str(a);
             full_write2_str("\n");
             i++;
-            a += strlen(a) + 1;
+            while (*a++ != '\0')
+                continue;
         }
         return 0;
@@ -727 +839 @@
     applet_name = bb_get_last_path_component_nostrip(argv[0]);
     run_applet_and_exit(applet_name, argv);
-
-    /*bb_error_msg_and_die("applet not found"); - sucks in printf */
-    full_write2_str(applet_name);
-    full_write2_str(": applet not found\n");
-    xfunc_die();
-}
+}
+# endif
 
 void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
@@ -743 +851 @@
     /* Reinit some shared global data */
     xfunc_error_retval = EXIT_FAILURE;
-
-    applet_name = APPLET_NAME(applet_no);
-    if (argc == 2 && strcmp(argv[1], "--help") == 0) {
-        /* Special case. POSIX says "test --help"
-         * should be no different from e.g. "test --foo".  */
-//TODO: just compare applet_no with APPLET_NO_test
-        if (!ENABLE_TEST || strcmp(applet_name, "test") != 0) {
-            /* If you want "foo --help" to return 0: */
-            /*xfunc_error_retval = 0;*/
+    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".
+     * Thus for "test", we skip --help check.
+     * "true" and "false" are also special.
+     */
+    if (1
+#if defined APPLET_NO_test
+     && applet_no != APPLET_NO_test
+#endif
+#if defined APPLET_NO_true
+     && applet_no != APPLET_NO_true
+#endif
+#if defined APPLET_NO_false
+     && applet_no != APPLET_NO_false
+#endif
+    ) {
+        if (argc == 2 && strcmp(argv[1], "--help") == 0) {
+            /* Make "foo --help" exit with 0: */
+            xfunc_error_retval = 0;
             bb_show_usage();
         }
@@ -760 +880 @@
 }
 
-void FAST_FUNC run_applet_and_exit(const char *name, char **argv)
-{
-    int applet = find_applet_by_name(name);
+static NORETURN void run_applet_and_exit(const char *name, char **argv)
+{
+    int applet;
+
+# if ENABLE_BUSYBOX
+    if (is_prefixed_with(name, "busybox"))
+        exit(busybox_main(argv));
+# endif
+    /* 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);
-    if (strncmp(name, "busybox", 7) == 0)
-        exit(busybox_main(argv));
+
+    /*bb_error_msg_and_die("applet not found"); - links in printf */
+    full_write2_str(applet_name);
+    full_write2_str(": applet not found\n");
+    /* POSIX: "If a command is not found, the exit status shall be 127" */
+    exit(127);
 }
 
@@ -779 +910 @@
 #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
@@ -804 +948 @@
 #if defined(SINGLE_APPLET_MAIN)
     /* Only one applet is selected in .config */
-    if (argv[1] && strncmp(argv[0], "busybox", 7) == 0) {
+    if (argv[1] && is_prefixed_with(argv[0], "busybox")) {
         /* "busybox <applet> <params>" should still work as expected */
         argv++;
@@ -814 +958 @@
     lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
 
+#if !ENABLE_BUSYBOX
+    if (argv[1] && is_prefixed_with(bb_basename(argv[0]), "busybox"))
+        argv++;
+#endif
     applet_name = argv[0];
     if (applet_name[0] == '-')
@@ -822 +970 @@
 
     run_applet_and_exit(applet_name, argv);
-
-    /*bb_error_msg_and_die("applet not found"); - sucks in printf */
-    full_write2_str(applet_name);
-    full_write2_str(": applet not found\n");
-    xfunc_die();
-#endif
-}
+#endif
+}