ash: introduce and use stzalloc and ckzalloc.

function                                             old     new   delta
stzalloc                                               -      29     +29
ckzalloc                                               -      29     +29
recordregion                                         108     102      -6
cmdlookup                                            158     152      -6
pipeline                                             188     181      -7
parseheredoc                                         135     128      -7
makename                                              42      35      -7
list                                                 355     348      -7
setvareq                                             221     212      -9
aliascmd                                             324     311     -13
pushfile                                              83      69     -14
readtoken1                                          2872    2849     -23
parse_command                                       1430    1391     -39
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 0/11 up/down: 58/-138)          Total: -80 bytes
   text    data     bss     dec     hex filename
 577227     706   23740  601673   92e49 busybox_old
 577147     706   23740  601593   92df9 busybox_unstripped

1 files changed, 60 insertions, 44 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 25c8fa521..65f94f682 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -1185,6 +1185,12 @@ ckmalloc(size_t nbytes)
         return ckrealloc(NULL, nbytes);
 }
 
+static void *
+ckzalloc(size_t nbytes)
+{
+        return memset(ckmalloc(nbytes), 0, nbytes);
+}
+
 /*
  * Make a copy of a string in safe storage.
  */
@@ -1238,6 +1244,12 @@ stalloc(size_t nbytes)
         return p;
 }
 
+static void *
+stzalloc(size_t nbytes)
+{
+        return memset(stalloc(nbytes), 0, nbytes);
+}
+
 static void
 stunalloc(void *p)
 {
@@ -2028,9 +2040,9 @@ setvareq(char *s, int flags)
                 if (flags & VNOSET)
                         return;
                 /* not found */
-                vp = ckmalloc(sizeof(*vp));
+                vp = ckzalloc(sizeof(*vp));
                 vp->next = *vpp;
-                vp->func = NULL;
+                /*vp->func = NULL; - ckzalloc did it */
                 *vpp = vp;
         }
         if (!(flags & (VTEXTFIXED|VSTACK|VNOSAVE)))
@@ -3072,11 +3084,11 @@ setalias(const char *name, const char *val)
                 ap->flag &= ~ALIASDEAD;
         } else {
                 /* not found */
-                ap = ckmalloc(sizeof(struct alias));
+                ap = ckzalloc(sizeof(struct alias));
                 ap->name = ckstrdup(name);
                 ap->val = ckstrdup(val);
-                ap->flag = 0;
-                ap->next = 0;
+                /*ap->flag = 0; - ckzalloc did it */
+                /*ap->next = NULL;*/
                 *app = ap;
         }
         INT_ON;
@@ -5222,8 +5234,8 @@ recordregion(int start, int end, int nulonly)
                 ifsp = &ifsfirst;
         } else {
                 INT_OFF;
-                ifsp = ckmalloc(sizeof(*ifsp));
-                ifsp->next = NULL;
+                ifsp = ckzalloc(sizeof(*ifsp));
+                /*ifsp->next = NULL; - ckzalloc did it */
                 ifslastp->next = ifsp;
                 INT_ON;
         }
@@ -6139,7 +6151,7 @@ ifsbreakup(char *string, struct arglist *arglist)
                                         continue;
                                 }
                                 *q = '\0';
-                                sp = stalloc(sizeof(*sp));
+                                sp = stzalloc(sizeof(*sp));
                                 sp->text = start;
                                 *arglist->lastp = sp;
                                 arglist->lastp = &sp->next;
@@ -6155,7 +6167,8 @@ ifsbreakup(char *string, struct arglist *arglist)
                                                 if (strchr(ifs, *p) == NULL ) {
                                                         p = q;
                                                         break;
-                                                } else if (strchr(defifs, *p) == NULL) {
+                                                }
+                                                if (strchr(defifs, *p) == NULL) {
                                                         if (ifsspc) {
                                                                 p++;
                                                                 ifsspc = 0;
@@ -6179,7 +6192,7 @@ ifsbreakup(char *string, struct arglist *arglist)
                 return;
 
  add:
-        sp = stalloc(sizeof(*sp));
+        sp = stzalloc(sizeof(*sp));
         sp->text = start;
         *arglist->lastp = sp;
         arglist->lastp = &sp->next;
@@ -6211,7 +6224,7 @@ addfname(const char *name)
 {
         struct strlist *sp;
 
-        sp = stalloc(sizeof(*sp));
+        sp = stzalloc(sizeof(*sp));
         sp->text = ststrdup(name);
         *exparg.lastp = sp;
         exparg.lastp = &sp->next;
@@ -6481,7 +6494,7 @@ expandarg(union node *arg, struct arglist *arglist, int flag)
         } else {
                 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
                         rmescapes(p);
-                sp = stalloc(sizeof(*sp));
+                sp = stzalloc(sizeof(*sp));
                 sp->text = p;
                 *exparg.lastp = sp;
                 exparg.lastp = &sp->next;
@@ -6644,7 +6657,7 @@ tryexec(char *cmd, char **argv, char **envp)
                 ap += 2;
                 argv++;
                 while ((*ap++ = *argv++))
-                        ;
+                        continue;
                 argv = new;
                 goto repeat;
         }
@@ -6781,9 +6794,9 @@ cmdlookup(const char *name, int add)
                 pp = &cmdp->next;
         }
         if (add && cmdp == NULL) {
-                cmdp = *pp = ckmalloc(sizeof(struct tblentry) - ARB
+                cmdp = *pp = ckzalloc(sizeof(struct tblentry) - ARB
                                         + strlen(name) + 1);
-                cmdp->next = NULL;
+                /*cmdp->next = NULL; - ckzalloc did it */
                 cmdp->cmdtype = CMDUNKNOWN;
                 strcpy(cmdp->cmdname, name);
         }
@@ -8903,11 +8916,11 @@ pushfile(void)
         parsefile->lleft = parselleft;
         parsefile->nextc = parsenextc;
         parsefile->linno = plinno;
-        pf = ckmalloc(sizeof(*pf));
+        pf = ckzalloc(sizeof(*pf));
         pf->prev = parsefile;
         pf->fd = -1;
-        pf->strpush = NULL;
-        pf->basestrpush.prev = NULL;
+        /*pf->strpush = NULL; - ckzalloc did it */
+        /*pf->basestrpush.prev = NULL;*/
         parsefile = pf;
 }
 
@@ -9537,9 +9550,9 @@ list(int nlflag)
                                 n2->npipe.backgnd = 1;
                         } else {
                                 if (n2->type != NREDIR) {
-                                        n3 = stalloc(sizeof(struct nredir));
+                                        n3 = stzalloc(sizeof(struct nredir));
                                         n3->nredir.n = n2;
-                                        n3->nredir.redirect = NULL;
+                                        /*n3->nredir.redirect = NULL; - stzalloc did it */
                                         n2 = n3;
                                 }
                                 n2->type = NBACKGND;
@@ -9629,9 +9642,9 @@ pipeline(void)
                 tokpushback = 1;
         n1 = parse_command();
         if (readtoken() == TPIPE) {
-                pipenode = stalloc(sizeof(struct npipe));
+                pipenode = stzalloc(sizeof(struct npipe));
                 pipenode->type = NPIPE;
-                pipenode->npipe.backgnd = 0;
+                /*pipenode->npipe.backgnd = 0; - stzalloc did it */
                 lp = stalloc(sizeof(struct nodelist));
                 pipenode->npipe.cmdlist = lp;
                 lp->n = n1;
@@ -9660,9 +9673,9 @@ makename(void)
 {
         union node *n;
 
-        n = stalloc(sizeof(struct narg));
+        n = stzalloc(sizeof(struct narg));
         n->type = NARG;
-        n->narg.next = NULL;
+        /*n->narg.next = NULL; - stzalloc did it */
         n->narg.text = wordtext;
         n->narg.backquote = backquotelist;
         return n;
@@ -9762,8 +9775,9 @@ simplecmd(void)
                 checkkwd = savecheckkwd;
                 switch (readtoken()) {
                 case TWORD:
-                        n = stalloc(sizeof(struct narg));
+                        n = stzalloc(sizeof(struct narg));
                         n->type = NARG;
+                        /*n->narg.next = NULL; - stzalloc did it */
                         n->narg.text = wordtext;
                         n->narg.backquote = backquotelist;
                         if (savecheckkwd && isassignment(wordtext)) {
@@ -9887,8 +9901,9 @@ parse_command(void)
                 if (readtoken() == TIN) {
                         app = ≈
                         while (readtoken() == TWORD) {
-                                n2 = stalloc(sizeof(struct narg));
+                                n2 = stzalloc(sizeof(struct narg));
                                 n2->type = NARG;
+                                /*n2->narg.next = NULL; - stzalloc did it */
                                 n2->narg.text = wordtext;
                                 n2->narg.backquote = backquotelist;
                                 *app = n2;
@@ -9899,11 +9914,11 @@ parse_command(void)
                         if (lasttoken != TNL && lasttoken != TSEMI)
                                 raise_error_unexpected_syntax(-1);
                 } else {
-                        n2 = stalloc(sizeof(struct narg));
+                        n2 = stzalloc(sizeof(struct narg));
                         n2->type = NARG;
+                        /*n2->narg.next = NULL; - stzalloc did it */
                         n2->narg.text = (char *)dolatstr;
-                        n2->narg.backquote = NULL;
-                        n2->narg.next = NULL;
+                        /*n2->narg.backquote = NULL;*/
                         n1->nfor.args = n2;
                         /*
                          * Newline or semicolon here is optional (but note
@@ -9923,11 +9938,11 @@ parse_command(void)
                 n1->type = NCASE;
                 if (readtoken() != TWORD)
                         raise_error_unexpected_syntax(TWORD);
-                n1->ncase.expr = n2 = stalloc(sizeof(struct narg));
+                n1->ncase.expr = n2 = stzalloc(sizeof(struct narg));
                 n2->type = NARG;
+                /*n2->narg.next = NULL; - stzalloc did it */
                 n2->narg.text = wordtext;
                 n2->narg.backquote = backquotelist;
-                n2->narg.next = NULL;
                 do {
                         checkkwd = CHKKWD | CHKALIAS;
                 } while (readtoken() == TNL);
@@ -9944,8 +9959,9 @@ parse_command(void)
                         cp->type = NCLIST;
                         app = &cp->nclist.pattern;
                         for (;;) {
-                                *app = ap = stalloc(sizeof(struct narg));
+                                *app = ap = stzalloc(sizeof(struct narg));
                                 ap->type = NARG;
+                                /*ap->narg.next = NULL; - stzalloc did it */
                                 ap->narg.text = wordtext;
                                 ap->narg.backquote = backquotelist;
                                 if (readtoken() != TPIPE)
@@ -9953,7 +9969,7 @@ parse_command(void)
                                 app = &ap->narg.next;
                                 readtoken();
                         }
-                        ap->narg.next = NULL;
+                        //ap->narg.next = NULL;
                         if (lasttoken != TRP)
                                 raise_error_unexpected_syntax(TRP);
                         cp->nclist.body = list(2);
@@ -9971,10 +9987,10 @@ parse_command(void)
                 *cpp = NULL;
                 goto redir;
         case TLP:
-                n1 = stalloc(sizeof(struct nredir));
+                n1 = stzalloc(sizeof(struct nredir));
                 n1->type = NSUBSHELL;
                 n1->nredir.n = list(0);
-                n1->nredir.redirect = NULL;
+                /*n1->nredir.redirect = NULL; - stzalloc did it */
                 t = TRP;
                 break;
         case TBEGIN:
@@ -10003,7 +10019,7 @@ parse_command(void)
         *rpp = NULL;
         if (redir) {
                 if (n1->type != NSUBSHELL) {
-                        n2 = stalloc(sizeof(struct nredir));
+                        n2 = stzalloc(sizeof(struct nredir));
                         n2->type = NREDIR;
                         n2->nredir.n = n1;
                         n1 = n2;
@@ -10301,7 +10317,7 @@ parseredir: {
         char fd = *out;
         union node *np;
 
-        np = stalloc(sizeof(struct nfile));
+        np = stzalloc(sizeof(struct nfile));
         if (c == '>') {
                 np->nfile.fd = 1;
                 c = pgetc();
@@ -10316,13 +10332,13 @@ parseredir: {
                         pungetc();
                 }
         } else {        /* c == '<' */
-                np->nfile.fd = 0;
+                /*np->nfile.fd = 0; - stzalloc did it */
                 c = pgetc();
                 switch (c) {
                 case '<':
                         if (sizeof(struct nfile) != sizeof(struct nhere)) {
-                                np = stalloc(sizeof(struct nhere));
-                                np->nfile.fd = 0;
+                                np = stzalloc(sizeof(struct nhere));
+                                /*np->nfile.fd = 0; - stzalloc did it */
                         }
                         np->type = NHERE;
                         heredoc = stalloc(sizeof(struct heredoc));
@@ -10573,8 +10589,8 @@ parsebackq: {
         nlpp = &bqlist;
         while (*nlpp)
                 nlpp = &(*nlpp)->next;
-        *nlpp = stalloc(sizeof(**nlpp));
-        (*nlpp)->next = NULL;
+        *nlpp = stzalloc(sizeof(**nlpp));
+        /* (*nlpp)->next = NULL; - stzalloc did it */
         parsebackquote = oldstyle;
 
         if (oldstyle) {
@@ -10930,9 +10946,9 @@ parseheredoc(void)
                 }
                 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
                                 here->eofmark, here->striptabs);
-                n = stalloc(sizeof(struct narg));
+                n = stzalloc(sizeof(struct narg));
                 n->narg.type = NARG;
-                n->narg.next = NULL;
+                /*n->narg.next = NULL; - stzalloc did it */
                 n->narg.text = wordtext;
                 n->narg.backquote = backquotelist;
                 here->here->nhere.doc = n;