Merge branch 'busybox' into merge

19 files changed, 331 insertions, 184 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 9214982c1..98da20f8a 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -351,19 +351,6 @@ typedef long arith_t;
 # error "Do not even bother, ash will not run on NOMMU machine"
 #endif
 
-/* We use a trick to have more optimized code (fewer pointer reloads):
- *  ash.c:   extern struct globals *const ash_ptr_to_globals;
- *  ash_ptr_hack.c: struct globals *ash_ptr_to_globals;
- * This way, compiler in ash.c knows the pointer can not change.
- *
- * However, this may break on weird arches or toolchains. In this case,
- * set "-DBB_GLOBAL_CONST=''" in CONFIG_EXTRA_CFLAGS to disable
- * this optimization.
- */
-#ifndef BB_GLOBAL_CONST
-# define BB_GLOBAL_CONST const
-#endif
-
 #if ENABLE_PLATFORM_MINGW32
 # define FORKSHELL_DEBUG 0
 
@@ -693,8 +680,7 @@ extern struct globals_misc *BB_GLOBAL_CONST ash_ptr_to_globals_misc;
 #endif
 
 #define INIT_G_misc() do { \
-        (*(struct globals_misc**)not_const_pp(&ash_ptr_to_globals_misc)) = xzalloc(sizeof(G_misc)); \
-        barrier(); \
+        XZALLOC_CONST_PTR(&ash_ptr_to_globals_misc, sizeof(G_misc)); \
         savestatus = -1; \
         curdir = nullstr; \
         physdir = nullstr; \
@@ -1783,8 +1769,7 @@ extern struct globals_memstack *BB_GLOBAL_CONST ash_ptr_to_globals_memstack;
 #define g_stacknleft (G_memstack.g_stacknleft)
 #define stackbase    (G_memstack.stackbase   )
 #define INIT_G_memstack() do { \
-        (*(struct globals_memstack**)not_const_pp(&ash_ptr_to_globals_memstack)) = xzalloc(sizeof(G_memstack)); \
-        barrier(); \
+        XZALLOC_CONST_PTR(&ash_ptr_to_globals_memstack, sizeof(G_memstack)); \
         g_stackp = &stackbase; \
         g_stacknxt = stackbase.space; \
         g_stacknleft = MINSIZE; \
@@ -2445,8 +2430,7 @@ extern struct globals_var *BB_GLOBAL_CONST ash_ptr_to_globals_var;
 #endif
 #define INIT_G_var() do { \
         unsigned i; \
-        (*(struct globals_var**)not_const_pp(&ash_ptr_to_globals_var)) = xzalloc(sizeof(G_var)); \
-        barrier(); \
+        XZALLOC_CONST_PTR(&ash_ptr_to_globals_var, sizeof(G_var)); \
         for (i = 0; i < ARRAY_SIZE(varinit_data); i++) { \
                 varinit[i].flags    = varinit_data[i].flags; \
                 varinit[i].var_text = varinit_data[i].var_text; \
@@ -7840,14 +7824,19 @@ subevalvar(char *start, char *str, int strloc,
                 if ((unsigned)len > (orig_len - pos))
                         len = orig_len - pos;
 
-                for (vstr = startp; pos; vstr++, pos--) {
-                        if (quotes && (unsigned char)*vstr == CTLESC)
+                if (!quotes) {
+                        loc = mempcpy(startp, startp + pos, len);
+                } else {
+                        for (vstr = startp; pos != 0; pos--) {
+                                if ((unsigned char)*vstr == CTLESC)
+                                        vstr++;
                                 vstr++;
-                }
-                for (loc = startp; len; len--) {
-                        if (quotes && (unsigned char)*vstr == CTLESC)
+                        }
+                        for (loc = startp; len != 0; len--) {
+                                if ((unsigned char)*vstr == CTLESC)
+                                        *loc++ = *vstr++;
                                 *loc++ = *vstr++;
-                        *loc++ = *vstr++;
+                        }
                 }
                 *loc = '\0';
                 goto out;
@@ -7901,7 +7890,7 @@ subevalvar(char *start, char *str, int strloc,
 #if BASH_PATTERN_SUBST
         workloc = expdest - (char *)stackblock();
         if (subtype == VSREPLACE || subtype == VSREPLACEALL) {
-                size_t no_meta_len;
+                size_t no_meta_len, first_escaped;
                 int len;
                 char *idx, *end;
 
@@ -7919,28 +7908,34 @@ subevalvar(char *start, char *str, int strloc,
                 if (str[0] == '\0')
                         goto out1;
 
-                no_meta_len = (ENABLE_ASH_OPTIMIZE_FOR_SIZE || strpbrk(str, "*?[\\")) ? 0 : strlen(str);
+                first_escaped = (str[0] == '\\' && str[1]);
+                /* "first_escaped" trick allows to treat e.g. "\*no_glob_chars"
+                 * as literal too (as it is semi-common, and easy to accomodate
+                 * by just using str + 1).
+                 */
+                no_meta_len = strpbrk(str + first_escaped * 2, "*?[\\") ? 0 : strlen(str);
                 len = 0;
                 idx = startp;
                 end = str - 1;
                 while (idx <= end) {
  try_to_match:
                         if (no_meta_len == 0) {
-                                /* pattern has meta chars, have to glob; or ENABLE_ASH_OPTIMIZE_FOR_SIZE */
+                                /* pattern has meta chars, have to glob */
                                 loc = scanright(idx, rmesc, rmescend, str, quotes, /*match_at_start:*/ 1);
                         } else {
                                 /* Testcase for very slow replace (performs about 22k replaces):
                                  * x=::::::::::::::::::::::
                                  * x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;echo ${#x}
                                  * echo "${x//:/|}"
+                                 * To test "first_escaped" logic, replace : with *.
                                  */
-                                if (strncmp(rmesc, str, no_meta_len) != 0)
+                                if (strncmp(rmesc, str + first_escaped, no_meta_len - first_escaped) != 0)
                                         goto no_match;
                                 loc = idx;
                                 if (!quotes) {
-                                        loc += no_meta_len;
+                                        loc += no_meta_len - first_escaped;
                                 } else {
-                                        size_t n = no_meta_len;
+                                        size_t n = no_meta_len - first_escaped;
                                         do {
                                                 if ((unsigned char)*loc == CTLESC)
                                                         loc++;
@@ -11811,14 +11806,14 @@ static void freestrings(struct strpush *sp)
         INT_OFF;
         do {
                 struct strpush *psp;
-
+#if ENABLE_ASH_ALIAS
                 if (sp->ap) {
                         sp->ap->flag &= ~ALIASINUSE;
                         if (sp->ap->flag & ALIASDEAD) {
                                 unalias(sp->ap->name);
                         }
                 }
-
+#endif
                 psp = sp;
                 sp = sp->spfree;
 
@@ -15497,7 +15492,7 @@ init(void)
 
 
 //usage:#define ash_trivial_usage
-//usage:        "[-il] [-|+Cabefmnuvx] [-|+o OPT]... [-c 'SCRIPT' [ARG0 ARGS] | FILE [ARGS] | -s [ARGS]]"
+//usage:        "[-il] [-|+Cabefmnuvx] [-|+o OPT]... [-c 'SCRIPT' [ARG0 ARGS] | FILE ARGS | -s ARGS]"
 ////////        comes from ^^^^^^^^^^optletters
 //usage:#define ash_full_usage "\n\n"
 //usage:        "Unix shell interpreter"
@@ -15764,13 +15759,12 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
         }
  state2:
         state = 3;
-        if (
+        if (iflag
 #if ENABLE_PLATFORM_POSIX
 #ifndef linux
-         getuid() == geteuid() && getgid() == getegid() &&
+         && getuid() == geteuid() && getgid() == getegid()
 #endif
 #endif
-         iflag
         ) {
                 const char *shinit = lookupvar("ENV");
                 if (shinit != NULL && *shinit != '\0')
diff --git a/shell/ash_test/ash-arith/arith-postinc.right b/shell/ash_test/ash-arith/arith-postinc.right
index c95ce02bf..5cd4ba6b4 100644
--- a/shell/ash_test/ash-arith/arith-postinc.right
+++ b/shell/ash_test/ash-arith/arith-postinc.right
@@ -2,4 +2,7 @@
 1 1
 1 1
 1 1
+6 6
+7 7
+7 7
 Ok:0
diff --git a/shell/ash_test/ash-arith/arith-postinc.tests b/shell/ash_test/ash-arith/arith-postinc.tests
index 3fd9bfed5..f2ae778df 100755
--- a/shell/ash_test/ash-arith/arith-postinc.tests
+++ b/shell/ash_test/ash-arith/arith-postinc.tests
@@ -2,4 +2,8 @@ echo 1 $((0++1))
 echo 1 $((0--1))
 x=-1; echo 1 $((0-$x))
 x=+1; echo 1 $((0+$x))
+a=3
+echo 6 $((a+++3))   # a++ + 3
+echo 7 $(((a)+++3)) # a + + + 3
+echo 7 $(((a)+++3)) # a + + + 3
 echo Ok:$?
diff --git a/shell/ash_test/ash-arith/arith.right b/shell/ash_test/ash-arith/arith.right
index 6936f1269..61fcab55e 100644
--- a/shell/ash_test/ash-arith/arith.right
+++ b/shell/ash_test/ash-arith/arith.right
@@ -43,40 +43,60 @@ Format: 'expected actual'
 4 4
 29 29
 5 5
+unary plus, minus
 -4 -4
 4 4
+conditional expressions
 1 1
 32 32
 32 32
 1 1
 1 1
 32 32
+check that the unevaluated part of the ternary operator does not do evaluation or assignment
 20 20
 30 30
 20 20
 30 30
-./arith.tests: line 117: arithmetic syntax error
+check precedence of assignment vs. conditional operator
+./arith.tests: line 116: arithmetic syntax error
+check precedence of assignment vs. conditional operator
+associativity of assignment-operator operator
 6 6
 6,5,3 6,5,3
+octal, hex
 263 263
 255 255
 40 40
-./arith.tests: line 163: arithmetic syntax error
-./arith.tests: line 165: divide by zero
-./arith.tests: let: line 166: arithmetic syntax error
-./arith.tests: line 167: arithmetic syntax error
-./arith.tests: let: line 168: arithmetic syntax error
+other bases
+10 10
+10 10
+10 10
+10 10
+10 10
+10 10
+36 36
+36 36
+62 62
+63 63
+missing number after base
+0 0
+./arith.tests: line 162: arithmetic syntax error
+./arith.tests: line 164: divide by zero
+./arith.tests: let: line 165: arithmetic syntax error
+./arith.tests: line 166: arithmetic syntax error
+./arith.tests: let: line 167: arithmetic syntax error
 abc
 def
 ghi
-./arith.tests: line 191: arithmetic syntax error
+./arith.tests: line 190: arithmetic syntax error
 16 16
-./arith.tests: line 196: arithmetic syntax error
-./arith.tests: line 197: malformed ?: operator
-./arith.tests: line 198: arithmetic syntax error
+./arith.tests: line 195: arithmetic syntax error
+./arith.tests: line 196: malformed ?: operator
+./arith.tests: line 197: arithmetic syntax error
 9 9
-./arith.tests: line 205: arithmetic syntax error
-./arith.tests: line 208: arithmetic syntax error
+./arith.tests: line 204: arithmetic syntax error
+./arith.tests: line 207: arithmetic syntax error
 9 9
 9 9
 9 9
@@ -97,14 +117,17 @@ ghi
 3 3
 4 4
 4 4
-./arith.tests: line 257: arithmetic syntax error
+7 7
+./arith.tests: line 256: arithmetic syntax error
+./arith.tests: line 258: arithmetic syntax error
 ./arith.tests: line 259: arithmetic syntax error
-./arith.tests: line 260: arithmetic syntax error
+./arith.tests: line 261: arithmetic syntax error
 ./arith.tests: line 262: arithmetic syntax error
-./arith.tests: line 263: arithmetic syntax error
 4 4
 7 7
 -7 -7
+7
+7
 ./arith1.sub: line 2: arithmetic syntax error
 ./arith1.sub: line 3: arithmetic syntax error
 ./arith1.sub: line 4: arithmetic syntax error
@@ -119,11 +142,12 @@ ghi
 2 2
 -2 -2
 1 1
-./arith1.sub: line 37: arithmetic syntax error
-./arith2.sub: line 2: arithmetic syntax error
-./arith2.sub: line 3: arithmetic syntax error
-./arith2.sub: line 4: arithmetic syntax error
-./arith2.sub: line 5: arithmetic syntax error
+7
+7
+7
+7
+7
+7
 5 5
 1 1
 6 6
@@ -132,11 +156,17 @@ ghi
 1 1
 4 4
 0 0
-./arith2.sub: line 42: arithmetic syntax error
-./arith2.sub: line 47: arithmetic syntax error
+-7
+-7
+7
+7
+-7 -7
+-7 -7
+7 7
+7 7
 8 12
-./arith.tests: line 290: arithmetic syntax error
+./arith.tests: line 289: arithmetic syntax error
 42
 42
 42
-./arith.tests: line 302: a[b[c]d]=e: not found
+./arith.tests: line 301: a[b[c]d]=e: not found
diff --git a/shell/ash_test/ash-arith/arith.tests b/shell/ash_test/ash-arith/arith.tests
index d65758e7d..b9cb8ba4c 100755
--- a/shell/ash_test/ash-arith/arith.tests
+++ b/shell/ash_test/ash-arith/arith.tests
@@ -75,11 +75,11 @@ echo 4 $(( iv &= 4 ))
 echo 29 $(( iv += (jv + 9)))
 echo 5 $(( (iv + 4) % 7 ))
 
-# unary plus, minus
+echo unary plus, minus
 echo -4 $(( +4 - 8 ))
 echo 4 $(( -4 + 8 ))
 
-# conditional expressions
+echo conditional expressions
 echo 1 $(( 4<5 ? 1 : 32))
 echo 32 $(( 4>5 ? 1 : 32))
 echo 32 $(( 4>(2+3) ? 1 : 32))
@@ -87,8 +87,7 @@ echo 1 $(( 4<(2+3) ? 1 : 32))
 echo 1 $(( (2+2)<(2+3) ? 1 : 32))
 echo 32 $(( (2+2)>(2+3) ? 1 : 32))
 
-# check that the unevaluated part of the ternary operator does not do
-# evaluation or assignment
+echo check that the unevaluated part of the ternary operator does not do evaluation or assignment
 x=i+=2
 y=j+=2
 #ash# declare -i i=1 j=1
@@ -109,20 +108,20 @@ echo 20 $((1 ? 20 : (x+=2)))
 echo 30 $((0 ? (y+=2) : 30))
 #ash# echo $i,$y             # ash mishandles this
 
-# check precedence of assignment vs. conditional operator
+echo check precedence of assignment vs. conditional operator
 # should be an error
 #ash# declare -i x=2
       x=2
 #ashnote# bash reports error but continues, ash aborts - using subshell to 'emulate' bash:
 (  y=$((1 ? 20 : x+=2))  )
 
-# check precedence of assignment vs. conditional operator
+echo check precedence of assignment vs. conditional operator
 #ash# declare -i x=2
       x=2
 # ash says "line NNN: syntax error: 0 ? x+=2 : 20"
 #ash# echo 20 $((0 ? x+=2 : 20))
 
-# associativity of assignment-operator operator
+echo associativity of assignment-operator operator
 #ash# declare -i i=1 j=2 k=3
 i=1
 j=2
@@ -130,7 +129,7 @@ k=3
 echo 6 $((i += j += k))
 echo 6,5,3 $i,$j,$k
 
-# octal, hex
+echo octal, hex
 echo 263 $(( 0x100 | 007 ))
 echo 255 $(( 0xff ))
 #ash# echo 255 $(( 16#ff ))
@@ -139,25 +138,25 @@ echo 255 $(( 0xff ))
 
 echo 40 $(( 8 ^ 32 ))
 
-#ash# # other bases
-#ash# echo 10 $(( 16#a ))
-#ash# echo 10 $(( 32#a ))
-#ash# echo 10 $(( 56#a ))
-#ash# echo 10 $(( 64#a ))
-#ash#
-#ash# echo 10 $(( 16#A ))
-#ash# echo 10 $(( 32#A ))
-#ash# echo 36 $(( 56#A ))
-#ash# echo 36 $(( 64#A ))
-#ash#
-#ash# echo 62 $(( 64#@ ))
-#ash# echo 63 $(( 64#_ ))
+echo other bases
+echo 10 $(( 16#a ))
+echo 10 $(( 32#a ))
+echo 10 $(( 56#a ))
+echo 10 $(( 64#a ))
+
+echo 10 $(( 16#A ))
+echo 10 $(( 32#A ))
+echo 36 $(( 56#A ))
+echo 36 $(( 64#A ))
+
+echo 62 $(( 64#@ ))
+echo 63 $(( 64#_ ))
 
 #ash# # weird bases (error)
 #ash# echo $(( 3425#56 ))
 
-#ash# # missing number after base
-#ash# echo 0 $(( 2# ))
+echo missing number after base
+echo 0 $(( 2# ))
 
 # these should generate errors
 (  echo $(( 7 = 43 ))      )
@@ -252,8 +251,8 @@ echo 3 $x
 echo 4 $(( ++x ))
 echo 4 $x
 
-# bash 3.2 apparently thinks that ++7 is 7
-#ash# echo 7 $(( ++7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo 7 $(( ++7 ))
 (  echo $(( 7-- ))    )
 
 (  echo $(( --x=7 ))  )
@@ -267,9 +266,9 @@ echo 4 $x
 echo 7 $(( +7 ))
 echo -7 $(( -7 ))
 
-# bash 3.2 apparently thinks that ++7 is 7
-#ash# echo $(( ++7 ))
-#ash# echo $(( --7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++7 ))
+echo $(( --7 ))
 
 ${THIS_SH} ./arith1.sub
 ${THIS_SH} ./arith2.sub
diff --git a/shell/ash_test/ash-arith/arith1.sub b/shell/ash_test/ash-arith/arith1.sub
index 80aa99922..a36785c67 100755
--- a/shell/ash_test/ash-arith/arith1.sub
+++ b/shell/ash_test/ash-arith/arith1.sub
@@ -35,6 +35,6 @@ echo 1 $a
 
 #ash# (( ++ ))
 (  echo $(( +++7 ))  )
-# bash 3.2 apparently thinks that ++ +7 is 7
-#ash# echo $(( ++ + 7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++ + 7 ))
 #ash# (( -- ))
diff --git a/shell/ash_test/ash-arith/arith2.sub b/shell/ash_test/ash-arith/arith2.sub
index 9105059db..8d7918114 100755
--- a/shell/ash_test/ash-arith/arith2.sub
+++ b/shell/ash_test/ash-arith/arith2.sub
@@ -1,4 +1,4 @@
-# bash 3.2 apparently thinks that ++7 is 7 etc
+# ++ and -- are not inc/dec operators on non-variables, they are + + and - - sequences
 (  echo $(( --7 ))   )
 (  echo $(( ++7 ))   )
 (  echo $(( -- 7 ))  )
@@ -37,21 +37,17 @@ echo 4 $(( 4 - -- a ))
 echo 0 $a
 
 #ash# (( -- ))
-# bash 3.2 apparently thinks that ---7 is -7
-#ash# echo $(( ---7 ))
+# -- is not a dec operator on non-variable, it is the - - sequence
+echo $(( ---7 ))
 (  echo $(( -- - 7 ))  )
 
 #ash# (( ++ ))
-# bash 3.2: 7
-#ash# echo 7 $(( ++7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++7 ))
 (  echo $(( ++ + 7 ))  )
 
-# bash 3.2: -7
-#ash# echo -7 $(( ++-7 ))
-# bash 3.2: -7
-#ash# echo -7 $(( ++ - 7 ))
+echo -7 $(( ++-7 ))
+echo -7 $(( ++ - 7 ))
 
-# bash 3.2: 7
-#ash# echo 7 $(( +--7 ))
-# bash 3.2: 7
-#ash# echo 7 $(( -- + 7 ))
+echo 7 $(( +--7 ))
+echo 7 $(( -- + 7 ))
diff --git a/shell/ash_test/ash-comm/comm.right b/shell/ash_test/ash-comm/comm.right
new file mode 100644
index 000000000..1d836656f
--- /dev/null
+++ b/shell/ash_test/ash-comm/comm.right
@@ -0,0 +1,6 @@
+./SCRIPT.sh:
+  /proc/N/comm: SCRIPT.sh
+exec ./SCRIPT.sh:
+  /proc/N/comm: SCRIPT.sh
+sh ./SCRIPT.sh:
+  /proc/N/comm: ash
diff --git a/shell/ash_test/ash-comm/comm.tests b/shell/ash_test/ash-comm/comm.tests
new file mode 100755
index 000000000..671bfc176
--- /dev/null
+++ b/shell/ash_test/ash-comm/comm.tests
@@ -0,0 +1,20 @@
+{
+echo "#!$THIS_SH"
+echo 'procdir=/proc/$$'
+#echo 'echo "  /proc/N/exe:  $(basename $(readlink $procdir/exe))"'
+echo 'echo "  /proc/N/comm: $(cat $procdir/comm)"'
+} >SCRIPT.sh
+chmod 755 SCRIPT.sh
+
+# comm field was wrong if CONFIG_FEATURE_PREFER_APPLETS=y
+echo './SCRIPT.sh:'
+./SCRIPT.sh
+
+# comm field was wrong if CONFIG_FEATURE_PREFER_APPLETS=y
+echo 'exec ./SCRIPT.sh:'
+(exec ./SCRIPT.sh)
+
+echo 'sh ./SCRIPT.sh:'
+$THIS_SH ./SCRIPT.sh
+
+rm SCRIPT.sh
diff --git a/shell/hush.c b/shell/hush.c
index 6d472337f..6a27b1634 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -339,7 +339,7 @@
  * therefore we don't show them either.
  */
 //usage:#define hush_trivial_usage
-//usage:        "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE [ARGS] | -s [ARGS]]"
+//usage:        "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE ARGS | -s ARGS]"
 //usage:#define hush_full_usage "\n\n"
 //usage:        "Unix shell interpreter"
 
@@ -373,7 +373,7 @@
 # define F_DUPFD_CLOEXEC F_DUPFD
 #endif
 
-#if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !(ENABLE_ASH || ENABLE_SH_IS_ASH || ENABLE_BASH_IS_ASH)
+#if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !ENABLE_SHELL_ASH
 # include "embedded_scripts.h"
 #else
 # define NUM_SCRIPTS 0
@@ -3360,7 +3360,7 @@ static int glob_brace(char *pattern, o_string *o, int n)
          * NEXT points past the terminator of the first element, and REST
          * points past the final }.  We will accumulate result names from
          * recursive runs for each brace alternative in the buffer using
-         * GLOB_APPEND.  */
+         * GLOB_APPEND. */
 
         p = begin + 1;
         while (1) {
@@ -6311,7 +6311,7 @@ static char *encode_then_expand_vararg(const char *str, int handle_squotes, int
 
 /* Expanding ARG in ${var+ARG}, ${var-ARG}
  */
-static int encode_then_append_var_plusminus(o_string *output, int n,
+static NOINLINE int encode_then_append_var_plusminus(o_string *output, int n,
                 char *str, int dquoted)
 {
         struct in_str input;
@@ -6472,16 +6472,21 @@ static arith_t expand_and_evaluate_arith(const char *arg, const char **errmsg_p)
 /* ${var/[/]pattern[/repl]} helpers */
 static char *strstr_pattern(char *val, const char *pattern, int *size)
 {
-        int sz = strcspn(pattern, "*?[\\");
-        if (pattern[sz] == '\0') {
+        int first_escaped = (pattern[0] == '\\' && pattern[1]);
+        /* "first_escaped" trick allows to treat e.g. "\*no_glob_chars"
+         * as literal too (as it is semi-common, and easy to accomodate
+         * by just using str + 1).
+         */
+        int sz = strcspn(pattern + first_escaped * 2, "*?[\\");
+        if ((pattern + first_escaped * 2)[sz] == '\0') {
                 /* Optimization for trivial patterns.
                  * Testcase for very slow replace (performs about 22k replaces):
                  * x=::::::::::::::::::::::
                  * x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;echo ${#x}
                  * echo "${x//:/|}"
                  */
-                *size = sz;
-                return strstr(val, pattern);
+                *size = sz + first_escaped;
+                return strstr(val, pattern + first_escaped);
         }
 
         while (1) {
@@ -10220,7 +10225,7 @@ int hush_main(int argc, char **argv)
 
         cached_getpid = getpid();   /* for tcsetpgrp() during init */
         G.root_pid = cached_getpid; /* for $PID  (NOMMU can override via -$HEXPID:HEXPPID:...) */
-        G.root_ppid = getppid();    /* for $PPID (NOMMU can override)  */
+        G.root_ppid = getppid();    /* for $PPID (NOMMU can override) */
 
         /* Deal with HUSH_VERSION */
         debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
@@ -10351,6 +10356,29 @@ int hush_main(int argc, char **argv)
                         /* Well, we cannot just declare interactiveness,
                          * we have to have some stuff (ctty, etc) */
                         /* G_interactive_fd++; */
+//There are a few cases where bash -i -c 'SCRIPT'
+//has visible effect (differs from bash -c 'SCRIPT'):
+//it ignores TERM:
+//      bash -i -c 'kill $$; echo ALIVE'
+//      ALIVE
+//it resets SIG_INGed HUP to SIG_DFL:
+//      trap '' hup; bash -i -c 'kill -hup $$; echo ALIVE'
+//      Hangup   [the message is not printed by bash, it's the shell which started it]
+//is talkative about jobs and exiting:
+//      bash -i -c 'sleep 1 & exit'
+//      [1] 16170
+//      exit
+//includes $ENV file (only if run as "sh"):
+//      echo last >/tmp/ENV; ENV=/tmp/ENV sh -i -c 'echo HERE'
+//      last: cannot open /var/log/wtmp: No such file or directory
+//      HERE
+//(under "bash", it's the opposite: it runs $BASH_ENV file only *without* -i).
+//
+//ash -i -c 'sleep 3; sleep 3', on ^C, drops into a prompt instead of exiting
+//(this may be a bug, bash does not do this).
+//(ash -i -c 'sleep 3' won't show this, the last command gets auto-"exec"ed)
+//
+//None of the above feel like useful features people would rely on.
                         break;
                 case 's':
                         G.opt_s = 1;
@@ -11727,7 +11755,7 @@ static int FAST_FUNC builtin_fg_bg(char **argv)
         /* TODO: bash prints a string representation
          * of job being foregrounded (like "sleep 1 | cat") */
         if (argv[0][0] == 'f' && G_saved_tty_pgrp) {
-                /* Put the job into the foreground.  */
+                /* Put the job into the foreground. */
                 tcsetpgrp(G_interactive_fd, pi->pgrp);
         }
 
diff --git a/shell/hush_test/hush-arith/arith-postinc.right b/shell/hush_test/hush-arith/arith-postinc.right
index c95ce02bf..5cd4ba6b4 100644
--- a/shell/hush_test/hush-arith/arith-postinc.right
+++ b/shell/hush_test/hush-arith/arith-postinc.right
@@ -2,4 +2,7 @@
 1 1
 1 1
 1 1
+6 6
+7 7
+7 7
 Ok:0
diff --git a/shell/hush_test/hush-arith/arith-postinc.tests b/shell/hush_test/hush-arith/arith-postinc.tests
index 3fd9bfed5..f2ae778df 100755
--- a/shell/hush_test/hush-arith/arith-postinc.tests
+++ b/shell/hush_test/hush-arith/arith-postinc.tests
@@ -2,4 +2,8 @@ echo 1 $((0++1))
 echo 1 $((0--1))
 x=-1; echo 1 $((0-$x))
 x=+1; echo 1 $((0+$x))
+a=3
+echo 6 $((a+++3))   # a++ + 3
+echo 7 $(((a)+++3)) # a + + + 3
+echo 7 $(((a)+++3)) # a + + + 3
 echo Ok:$?
diff --git a/shell/hush_test/hush-arith/arith.right b/shell/hush_test/hush-arith/arith.right
index c48e468a5..a8612295e 100644
--- a/shell/hush_test/hush-arith/arith.right
+++ b/shell/hush_test/hush-arith/arith.right
@@ -70,6 +70,19 @@ octal, hex
 263 263
 255 255
 40 40
+other bases
+10 10
+10 10
+10 10
+10 10
+10 10
+10 10
+36 36
+36 36
+62 62
+63 63
+missing number after base
+0 0
 hush: arithmetic syntax error
 hush: divide by zero
 hush: can't execute 'let': No such file or directory
@@ -106,6 +119,7 @@ hush: arithmetic syntax error
 3 3
 4 4
 4 4
+7 7
 hush: arithmetic syntax error
 hush: arithmetic syntax error
 hush: arithmetic syntax error
@@ -114,6 +128,8 @@ hush: arithmetic syntax error
 4 4
 7 7
 -7 -7
+7
+7
 hush: arithmetic syntax error
 hush: arithmetic syntax error
 hush: arithmetic syntax error
@@ -128,11 +144,12 @@ hush: arithmetic syntax error
 2 2
 -2 -2
 1 1
-hush: arithmetic syntax error
-hush: arithmetic syntax error
-hush: arithmetic syntax error
-hush: arithmetic syntax error
-hush: arithmetic syntax error
+7
+7
+7
+7
+7
+7
 5 5
 1 1
 6 6
@@ -141,8 +158,14 @@ hush: arithmetic syntax error
 1 1
 4 4
 0 0
-hush: arithmetic syntax error
-hush: arithmetic syntax error
+-7
+-7
+7
+7
+-7 -7
+-7 -7
+7 7
+7 7
 8 12
 hush: arithmetic syntax error
 42
diff --git a/shell/hush_test/hush-arith/arith.tests b/shell/hush_test/hush-arith/arith.tests
index bc6b341d1..6b707486c 100755
--- a/shell/hush_test/hush-arith/arith.tests
+++ b/shell/hush_test/hush-arith/arith.tests
@@ -142,25 +142,25 @@ echo 255 $(( 0xff ))
 
 echo 40 $(( 8 ^ 32 ))
 
-#ash# # other bases
-#ash# echo 10 $(( 16#a ))
-#ash# echo 10 $(( 32#a ))
-#ash# echo 10 $(( 56#a ))
-#ash# echo 10 $(( 64#a ))
-#ash#
-#ash# echo 10 $(( 16#A ))
-#ash# echo 10 $(( 32#A ))
-#ash# echo 36 $(( 56#A ))
-#ash# echo 36 $(( 64#A ))
-#ash#
-#ash# echo 62 $(( 64#@ ))
-#ash# echo 63 $(( 64#_ ))
+echo other bases
+echo 10 $(( 16#a ))
+echo 10 $(( 32#a ))
+echo 10 $(( 56#a ))
+echo 10 $(( 64#a ))
+
+echo 10 $(( 16#A ))
+echo 10 $(( 32#A ))
+echo 36 $(( 56#A ))
+echo 36 $(( 64#A ))
+
+echo 62 $(( 64#@ ))
+echo 63 $(( 64#_ ))
 
 #ash# # weird bases (error)
 #ash# echo $(( 3425#56 ))
 
-#ash# # missing number after base
-#ash# echo 0 $(( 2# ))
+echo missing number after base
+echo 0 $(( 2# ))
 
 # these should generate errors
 (  echo $(( 7 = 43 ))      )
@@ -255,8 +255,8 @@ echo 3 $x
 echo 4 $(( ++x ))
 echo 4 $x
 
-# bash 3.2 apparently thinks that ++7 is 7
-#ash# echo 7 $(( ++7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo 7 $(( ++7 ))
 (  echo $(( 7-- ))    )
 
 (  echo $(( --x=7 ))  )
@@ -270,9 +270,9 @@ echo 4 $x
 echo 7 $(( +7 ))
 echo -7 $(( -7 ))
 
-# bash 3.2 apparently thinks that ++7 is 7
-#ash# echo $(( ++7 ))
-#ash# echo $(( --7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++7 ))
+echo $(( --7 ))
 
 ${THIS_SH} ./arith1.sub
 ${THIS_SH} ./arith2.sub
diff --git a/shell/hush_test/hush-arith/arith1.sub b/shell/hush_test/hush-arith/arith1.sub
index 80aa99922..a36785c67 100755
--- a/shell/hush_test/hush-arith/arith1.sub
+++ b/shell/hush_test/hush-arith/arith1.sub
@@ -35,6 +35,6 @@ echo 1 $a
 
 #ash# (( ++ ))
 (  echo $(( +++7 ))  )
-# bash 3.2 apparently thinks that ++ +7 is 7
-#ash# echo $(( ++ + 7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++ + 7 ))
 #ash# (( -- ))
diff --git a/shell/hush_test/hush-arith/arith2.sub b/shell/hush_test/hush-arith/arith2.sub
index 9105059db..8d7918114 100755
--- a/shell/hush_test/hush-arith/arith2.sub
+++ b/shell/hush_test/hush-arith/arith2.sub
@@ -1,4 +1,4 @@
-# bash 3.2 apparently thinks that ++7 is 7 etc
+# ++ and -- are not inc/dec operators on non-variables, they are + + and - - sequences
 (  echo $(( --7 ))   )
 (  echo $(( ++7 ))   )
 (  echo $(( -- 7 ))  )
@@ -37,21 +37,17 @@ echo 4 $(( 4 - -- a ))
 echo 0 $a
 
 #ash# (( -- ))
-# bash 3.2 apparently thinks that ---7 is -7
-#ash# echo $(( ---7 ))
+# -- is not a dec operator on non-variable, it is the - - sequence
+echo $(( ---7 ))
 (  echo $(( -- - 7 ))  )
 
 #ash# (( ++ ))
-# bash 3.2: 7
-#ash# echo 7 $(( ++7 ))
+# ++ is not a inc operator on non-variable, it is the + + sequence
+echo $(( ++7 ))
 (  echo $(( ++ + 7 ))  )
 
-# bash 3.2: -7
-#ash# echo -7 $(( ++-7 ))
-# bash 3.2: -7
-#ash# echo -7 $(( ++ - 7 ))
+echo -7 $(( ++-7 ))
+echo -7 $(( ++ - 7 ))
 
-# bash 3.2: 7
-#ash# echo 7 $(( +--7 ))
-# bash 3.2: 7
-#ash# echo 7 $(( -- + 7 ))
+echo 7 $(( +--7 ))
+echo 7 $(( -- + 7 ))
diff --git a/shell/hush_test/hush-comm/comm.right b/shell/hush_test/hush-comm/comm.right
new file mode 100644
index 000000000..1b62b617e
--- /dev/null
+++ b/shell/hush_test/hush-comm/comm.right
@@ -0,0 +1,6 @@
+./SCRIPT.sh:
+  /proc/N/comm: SCRIPT.sh
+exec ./SCRIPT.sh:
+  /proc/N/comm: SCRIPT.sh
+sh ./SCRIPT.sh:
+  /proc/N/comm: hush
diff --git a/shell/hush_test/hush-comm/comm.tests b/shell/hush_test/hush-comm/comm.tests
new file mode 100755
index 000000000..671bfc176
--- /dev/null
+++ b/shell/hush_test/hush-comm/comm.tests
@@ -0,0 +1,20 @@
+{
+echo "#!$THIS_SH"
+echo 'procdir=/proc/$$'
+#echo 'echo "  /proc/N/exe:  $(basename $(readlink $procdir/exe))"'
+echo 'echo "  /proc/N/comm: $(cat $procdir/comm)"'
+} >SCRIPT.sh
+chmod 755 SCRIPT.sh
+
+# comm field was wrong if CONFIG_FEATURE_PREFER_APPLETS=y
+echo './SCRIPT.sh:'
+./SCRIPT.sh
+
+# comm field was wrong if CONFIG_FEATURE_PREFER_APPLETS=y
+echo 'exec ./SCRIPT.sh:'
+(exec ./SCRIPT.sh)
+
+echo 'sh ./SCRIPT.sh:'
+$THIS_SH ./SCRIPT.sh
+
+rm SCRIPT.sh
diff --git a/shell/math.c b/shell/math.c
index 2942cdd26..76d22c9bd 100644
--- a/shell/math.c
+++ b/shell/math.c
@@ -116,10 +116,6 @@
 #include "libbb.h"
 #include "math.h"
 
-#define lookupvar (math_state->lookupvar)
-#define setvar    (math_state->setvar   )
-//#define endofname (math_state->endofname)
-
 typedef unsigned char operator;
 
 /* An operator's token id is a bit of a bitfield. The lower 5 bits are the
@@ -258,7 +254,7 @@ static const char*
 arith_lookup_val(arith_state_t *math_state, var_or_num_t *t)
 {
         if (t->var) {
-                const char *p = lookupvar(t->var);
+                const char *p = math_state->lookupvar(t->var);
                 if (p) {
                         remembered_name *cur;
                         remembered_name cur_save;
@@ -445,16 +441,15 @@ arith_apply(arith_state_t *math_state, operator op, var_or_num_t *numstack, var_
 
                 if (top_of_stack->var == NULL) {
                         /* Hmm, 1=2 ? */
-//TODO: actually, bash allows ++7 but for some reason it evals to 7, not 8
                         goto err;
                 }
                 /* Save to shell variable */
                 sprintf(buf, ARITH_FMT, rez);
-                setvar(top_of_stack->var, buf);
+                math_state->setvar(top_of_stack->var, buf);
                 /* After saving, make previous value for v++ or v-- */
                 if (op == TOK_POST_INC)
                         rez--;
-                else if (op == TOK_POST_DEC)
+                if (op == TOK_POST_DEC)
                         rez++;
         }
 
@@ -607,11 +602,9 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                 const char *p;
                 operator op;
                 operator prec;
-                char arithval;
 
                 expr = skip_whitespace(expr);
-                arithval = *expr;
-                if (arithval == '\0') {
+                if (*expr == '\0') {
                         if (expr == start_expr) {
                                 /* Null expression */
                                 numstack->val = 0;
@@ -628,6 +621,7 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                                  * append a closing right paren
                                  * and let the loop process it */
                                 expr = ptr_to_rparen;
+//bb_error_msg("expr=')'");
                                 continue;
                         }
                         /* At this point, we're done with the expression */
@@ -635,19 +629,16 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                                 /* ...but if there isn't, it's bad */
                                 goto err;
                         }
-                        if (numstack->var) {
-                                /* expression is $((var)) only, lookup now */
-                                errmsg = arith_lookup_val(math_state, numstack);
-                        }
                         goto ret;
                 }
 
                 p = endofname(expr);
                 if (p != expr) {
                         /* Name */
-                        size_t var_name_size = (p-expr) + 1;  /* +1 for NUL */
+                        size_t var_name_size = (p - expr) + 1;  /* +1 for NUL */
                         numstackptr->var = alloca(var_name_size);
                         safe_strncpy(numstackptr->var, expr, var_name_size);
+//bb_error_msg("var:'%s'", numstackptr->var);
                         expr = p;
  num:
                         numstackptr->second_val_present = 0;
@@ -656,11 +647,12 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                         continue;
                 }
 
-                if (isdigit(arithval)) {
+                if (isdigit(*expr)) {
                         /* Number */
                         numstackptr->var = NULL;
                         errno = 0;
                         numstackptr->val = strto_arith_t(expr, (char**) &expr);
+//bb_error_msg("val:%lld", numstackptr->val);
                         if (errno)
                                 numstackptr->val = 0; /* bash compat */
                         goto num;
@@ -668,19 +660,26 @@ evaluate_string(arith_state_t *math_state, const char *expr)
 
                 /* Should be an operator */
 
-                /* Special case: NUM-- and NUM++ are not recognized if NUM
-                 * is a literal number, not a variable. IOW:
+                /* Special case: XYZ--, XYZ++, --XYZ, ++XYZ are recognized
+                 * only if XYZ is a variable name, not a number or EXPR. IOW:
                  * "a+++v" is a++ + v.
+                 * "(a)+++7" is ( a ) + + + 7.
                  * "7+++v" is 7 + ++v, not 7++ + v.
+                 * "--7" is - - 7, not --7.
+                 * "++++a" is + + ++a, not ++ ++a.
                  */
-                if (lasttok == TOK_NUM && !numstackptr[-1].var /* number literal */
-                 && (expr[0] == '+' || expr[0] == '-')
+                if ((expr[0] == '+' || expr[0] == '-')
                  && (expr[1] == expr[0])
                 ) {
-                        //bb_error_msg("special %c%c", expr[0], expr[0]);
-                        op = (expr[0] == '+' ? TOK_ADD : TOK_SUB);
-                        expr += 1;
-                        goto tok_found1;
+                        if (numstackptr == numstack || !numstackptr[-1].var) { /* not a VAR++ */
+                                char next = skip_whitespace(expr + 2)[0];
+                                if (!(isalpha(next) || next == '_')) { /* not a ++VAR */
+                                        //bb_error_msg("special %c%c", expr[0], expr[0]);
+                                        op = (expr[0] == '+' ? TOK_ADD : TOK_SUB);
+                                        expr++;
+                                        goto tok_found1;
+                                }
+                        }
                 }
 
                 p = op_tokens;
@@ -749,26 +748,40 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                  * "applied" in this way.
                  */
                 prec = PREC(op);
+//bb_error_msg("prec:%02x", prec);
                 if ((prec > 0 && prec < UNARYPREC) || prec == SPEC_PREC) {
                         /* not left paren or unary */
                         if (lasttok != TOK_NUM) {
                                 /* binary op must be preceded by a num */
                                 goto err;
                         }
+                        /* The algorithm employed here is simple: while we don't
+                         * hit an open paren nor the bottom of the stack, pop
+                         * tokens and apply them */
                         while (stackptr != stack) {
                                 operator prev_op = *--stackptr;
                                 if (op == TOK_RPAREN) {
-                                        /* The algorithm employed here is simple: while we don't
-                                         * hit an open paren nor the bottom of the stack, pop
-                                         * tokens and apply them */
+//bb_error_msg("op == TOK_RPAREN");
                                         if (prev_op == TOK_LPAREN) {
+//bb_error_msg("prev_op == TOK_LPAREN");
+//bb_error_msg("  %p %p numstackptr[-1].var:'%s'", numstack, numstackptr-1, numstackptr[-1].var);
+                                                if (numstackptr[-1].var) {
+                                                        /* Expression is (var), lookup now */
+                                                        errmsg = arith_lookup_val(math_state, &numstackptr[-1]);
+                                                        if (errmsg)
+                                                                goto err_with_custom_msg;
+                                                        /* Erase var name: (var) is just a number, for example, (var) = 1 is not valid */
+                                                        numstackptr[-1].var = NULL;
+                                                }
                                                 /* Any operator directly after a
                                                  * close paren should consider itself binary */
                                                 lasttok = TOK_NUM;
                                                 goto next;
                                         }
+//bb_error_msg("prev_op != TOK_LPAREN");
                                 } else {
                                         operator prev_prec = PREC(prev_op);
+//bb_error_msg("op != TOK_RPAREN");
                                         fix_assignment_prec(prec);
                                         fix_assignment_prec(prev_prec);
                                         if (prev_prec < prec
@@ -778,6 +791,7 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                                                 break;
                                         }
                                 }
+//bb_error_msg("arith_apply(prev_op:%02x)", prev_op);
                                 errmsg = arith_apply(math_state, prev_op, numstack, &numstackptr);
                                 if (errmsg)
                                         goto err_with_custom_msg;
@@ -787,6 +801,7 @@ evaluate_string(arith_state_t *math_state, const char *expr)
                 }
 
                 /* Push this operator to the stack and remember it */
+//bb_error_msg("push op:%02x", op);
                 *stackptr++ = lasttok = op;
  next: ;
         } /* while (1) */