ash: revert previous implementation of "A=1 A=2 B=$A cmd" code

Reverts this:

    commit 0e6f661e23d358cca104c24f8438d0ec64df32f1
    Date:   Fri Feb 15 15:02:15 2008 +0000
    ash: handle "A=1 A=2 B=$A; echo $B". closes bug 947.

A different fix from upstream has been imported by previous six commits.

Last seven commits, cumulative:

function                                             old     new   delta
poplocalvars                                           -     314    +314
mklocal                                                -     288    +288
pushlocalvars                                          -      48     +48
evalcommand                                         1372    1408     +36
unwindlocalvars                                        -      22     +22
ash_main                                            1022    1029      +7
setvar                                               167     172      +5
localvar_stack                                         -       4      +4
setvareq                                             303     302      -1
evalcase                                             271     269      -2
subevalvar                                          1202    1198      -4
localvars                                              4       -      -4
cmdenviron                                             4       -      -4
expandarg                                            984     973     -11
evalvar                                              589     574     -15
argstr                                              1164    1141     -23
dotcmd                                               335     303     -32
bltinlookup                                           51       5     -46
varvalue                                             709     596    -113
evalfun                                              456     270    -186
localcmd                                             364      44    -320
------------------------------------------------------------------------------
(add/remove: 5/2 grow/shrink: 3/11 up/down: 724/-761)         Total: -37 bytes
   text	   data	    bss	    dec	    hex	filename
 915353	    485	   6888	 922726	  e1466	busybox_old
 915320	    485	   6880	 922685	  e143d	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 15 insertions, 47 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 5bb59355c..faa42e28c 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -6304,19 +6304,15 @@ expari(int flag)
 #endif
 
 /* argstr needs it */
-static char *evalvar(char *p, int flags, struct strlist *var_str_list);
+static char *evalvar(char *p, int flags);
 
 /*
  * Perform variable and command substitution.  If EXP_FULL is set, output CTLESC
  * characters to allow for further processing.  Otherwise treat
  * $@ like $* since no splitting will be performed.
- *
- * var_str_list (can be NULL) is a list of "VAR=val" strings which take precedence
- * over shell variables. Needed for "A=a B=$A; echo $B" case - we use it
- * for correct expansion of "B=$A" word.
  */
 static void
-argstr(char *p, int flags, struct strlist *var_str_list)
+argstr(char *p, int flags)
 {
         static const char spclchars[] ALIGN1 = {
                 '=',
@@ -6409,7 +6405,7 @@ argstr(char *p, int flags, struct strlist *var_str_list)
                         inquotes ^= EXP_QUOTED;
                         /* "$@" syntax adherence hack */
                         if (inquotes && !memcmp(p, dolatstr + 1, DOLATSTRLEN - 1)) {
-                                p = evalvar(p + 1, flags | inquotes, /* var_str_list: */ NULL) + 1;
+                                p = evalvar(p + 1, flags | inquotes) + 1;
                                 goto start;
                         }
  addquote:
@@ -6435,7 +6431,7 @@ argstr(char *p, int flags, struct strlist *var_str_list)
                         goto addquote;
                 case CTLVAR:
                         TRACE(("argstr: evalvar('%s')\n", p));
-                        p = evalvar(p, flags | inquotes, var_str_list);
+                        p = evalvar(p, flags | inquotes);
                         TRACE(("argstr: evalvar:'%s'\n", (char *)stackblock()));
                         goto start;
                 case CTLBACKQ:
@@ -6577,7 +6573,7 @@ varunset(const char *end, const char *var, const char *umsg, int varflags)
 
 static const char *
 subevalvar(char *p, char *varname, int strloc, int subtype,
-                int startloc, int varflags, int flag, struct strlist *var_str_list)
+                int startloc, int varflags, int flag)
 {
         struct nodelist *saveargbackq = argbackq;
         int quotes = flag & QUOTES_ESC;
@@ -6595,8 +6591,8 @@ subevalvar(char *p, char *varname, int strloc, int subtype,
         //              p, varname, strloc, subtype, startloc, varflags, quotes);
 
         argstr(p, EXP_TILDE | (subtype != VSASSIGN && subtype != VSQUESTION ?
-                        (flag & (EXP_QUOTED | EXP_QPAT) ? EXP_QPAT : EXP_CASE) : 0),
-                        var_str_list);
+                        (flag & (EXP_QUOTED | EXP_QPAT) ? EXP_QPAT : EXP_CASE) : 0)
+        );
         STPUTC('\0', expdest);
         argbackq = saveargbackq;
         startp = (char *)stackblock() + startloc;
@@ -6873,7 +6869,7 @@ subevalvar(char *p, char *varname, int strloc, int subtype,
  * ash -c 'echo ${#1#}'  name:'1=#'
  */
 static NOINLINE ssize_t
-varvalue(char *name, int varflags, int flags, struct strlist *var_str_list, int *quotedp)
+varvalue(char *name, int varflags, int flags, int *quotedp)
 {
         const char *p;
         int num;
@@ -6965,31 +6961,6 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list, int
                 goto value;
         default:
                 /* NB: name has form "VAR=..." */
-
-                /* "A=a B=$A" case: var_str_list is a list of "A=a" strings
-                 * which should be considered before we check variables. */
-                if (var_str_list) {
-                        unsigned name_len = (strchrnul(name, '=') - name) + 1;
-                        p = NULL;
-                        do {
-                                char *str, *eq;
-                                str = var_str_list->text;
-                                eq = strchr(str, '=');
-                                if (!eq) /* stop at first non-assignment */
-                                        break;
-                                eq++;
-                                if (name_len == (unsigned)(eq - str)
-                                 && strncmp(str, name, name_len) == 0
-                                ) {
-                                        p = eq;
-                                        /* goto value; - WRONG! */
-                                        /* think "A=1 A=2 B=$A" */
-                                }
-                                var_str_list = var_str_list->next;
-                        } while (var_str_list);
-                        if (p)
-                                goto value;
-                }
                 p = lookupvar(name);
  value:
                 if (!p)
@@ -7019,7 +6990,7 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list, int
  * input string.
  */
 static char *
-evalvar(char *p, int flag, struct strlist *var_str_list)
+evalvar(char *p, int flag)
 {
         char varflags;
         char subtype;
@@ -7043,7 +7014,7 @@ evalvar(char *p, int flag, struct strlist *var_str_list)
         p = strchr(p, '=') + 1; //TODO: use var_end(p)?
 
  again:
-        varlen = varvalue(var, varflags, flag, var_str_list, &quoted);
+        varlen = varvalue(var, varflags, flag, &quoted);
         if (varflags & VSNUL)
                 varlen--;
 
@@ -7057,8 +7028,7 @@ evalvar(char *p, int flag, struct strlist *var_str_list)
                 if (varlen < 0) {
                         argstr(
                                 p,
-                                flag | EXP_TILDE | EXP_WORD,
-                                var_str_list
+                                flag | EXP_TILDE | EXP_WORD
                         );
                         goto end;
                 }
@@ -7070,7 +7040,7 @@ evalvar(char *p, int flag, struct strlist *var_str_list)
                         goto record;
 
                 subevalvar(p, var, 0, subtype, startloc, varflags,
-                           flag & ~QUOTES_ESC, var_str_list);
+                           flag & ~QUOTES_ESC);
                 varflags &= ~VSNUL;
                 /*
                  * Remove any recorded regions beyond
@@ -7123,7 +7093,7 @@ evalvar(char *p, int flag, struct strlist *var_str_list)
                 STPUTC('\0', expdest);
                 patloc = expdest - (char *)stackblock();
                 if (NULL == subevalvar(p, /* varname: */ NULL, patloc, subtype,
-                                startloc, varflags, flag, var_str_list)) {
+                                startloc, varflags, flag)) {
                         int amount = expdest - (
                                 (char *)stackblock() + patloc - 1
                         );
@@ -7547,8 +7517,7 @@ expandarg(union node *arg, struct arglist *arglist, int flag)
         argbackq = arg->narg.backquote;
         STARTSTACKSTR(expdest);
         TRACE(("expandarg: argstr('%s',flags:%x)\n", arg->narg.text, flag));
-        argstr(arg->narg.text, flag,
-                        /* var_str_list: */ arglist ? arglist->list : NULL);
+        argstr(arg->narg.text, flag);
         p = _STPUTC('\0', expdest);
         expdest = p - 1;
         if (arglist == NULL) {
@@ -7615,8 +7584,7 @@ casematch(union node *pattern, char *val)
         setstackmark(&smark);
         argbackq = pattern->narg.backquote;
         STARTSTACKSTR(expdest);
-        argstr(pattern->narg.text, EXP_TILDE | EXP_CASE,
-                        /* var_str_list: */ NULL);
+        argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
         STACKSTRNUL(expdest);
         ifsfree();
         result = patmatch(stackblock(), val);