Now that the only thing protected by setjmp/longjmp is the saved string, we can allocate it on the stack to get rid of the jump.
Based on commit bd35d8e from git://git.kernel.org/pub/scm/utils/dash/dash.git by Herbert Xu. function old new delta readtoken1 3182 3116 -66 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-66) Total: -66 bytes Signed-off-by: Ron Yorston <r...@pobox.com> --- shell/ash.c | 36 ++---------------------------------- 1 file changed, 2 insertions(+), 34 deletions(-) diff --git a/shell/ash.c b/shell/ash.c index 1b33fbd..531e9e2 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -11133,19 +11133,6 @@ readtoken1(int c, int syntax, char *eofmark, int striptabs) IF_ASH_BASH_COMPAT(smallint bash_dollar_squote = 0;) -#if __GNUC__ - /* Avoid longjmp clobbering */ - (void) &out; - (void) "ef; - (void) &dblquote; - (void) &varnest; - (void) &arinest; - (void) &parenlevel; - (void) &dqvarnest; - (void) &oldstyle; - (void) &prevsyntax; - (void) &syntax; -#endif startlinno = g_parsefile->linno; bqlist = NULL; quotef = 0; @@ -11610,30 +11597,16 @@ parsesub: { parsebackq: { struct nodelist **nlpp; union node *n; - char *volatile str; - struct jmploc jmploc; - struct jmploc *volatile savehandler; + char *str; size_t savelen; smallint saveprompt = 0; -#ifdef __GNUC__ - (void) &saveprompt; -#endif - if (setjmp(jmploc.loc)) { - free(str); - exception_handler = savehandler; - longjmp(exception_handler->loc, 1); - } - INT_OFF; str = NULL; savelen = out - (char *)stackblock(); if (savelen > 0) { - str = ckmalloc(savelen); + str = alloca(savelen); memcpy(str, stackblock(), savelen); } - savehandler = exception_handler; - exception_handler = &jmploc; - INT_ON; if (oldstyle) { /* We must read until the closing backquote, giving special * treatment to some slashes, and then push the string and @@ -11732,12 +11705,7 @@ parsebackq: { if (str) { memcpy(out, str, savelen); STADJUST(savelen, out); - INT_OFF; - free(str); - str = NULL; - INT_ON; } - exception_handler = savehandler; USTPUTC(CTLBACKQ, out); if (oldstyle) goto parsebackq_oldreturn; -- 2.4.3 _______________________________________________ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox