9base

revived minimalist port of Plan 9 userland to Unix
git clone git://git.suckless.org/9base
Log | Files | Refs | README | LICENSE

commit 1583c9239d968bbc571190d2cf563146a9704528
parent de27e3fba58c3dd467c29ea9a1aea6f9e65a5299
Author: pranomostro <pranomestro@gmail.com>
Date:   Sat, 20 May 2017 01:06:03 +0200

apply changes from https://github.com/9fans/plan9port on rc/havefork.c

before applying those changes, rc exited with sigsegv when receiving
sigint while executing a command in a subshell (example: rc -c '`{read}').

Diffstat:
rc/havefork.c | 123+++++++++++++++++++++++++++++++++++++++++++++++--------------------------------
1 file changed, 74 insertions(+), 49 deletions(-)

diff --git a/rc/havefork.c b/rc/havefork.c @@ -1,3 +1,5 @@ +#include <u.h> +#include <signal.h> #include "rc.h" #include "getflags.h" #include "exec.h" @@ -71,31 +73,23 @@ Xpipe(void) } } -char* -erealloc(char *p, long n) -{ - p = realloc(p, n); /* botch, should be Realloc */ - if(p==0) - panic("Can't realloc %d bytes\n", n); - return p; -} - /* * Who should wait for the exit from the fork? */ -enum { Stralloc = 100, }; - void Xbackq(void) { - int c, l, pid; - int pfd[2]; - char *s, *wd, *ewd, *stop; + struct thread *p = runq; + char wd[8193]; + int c, n; + char *s, *ewd=&wd[8192], *stop, *q; struct io *f; var *ifs = vlook("ifs"); word *v, *nextv; - - stop = ifs->val? ifs->val->word: ""; + int pfd[2]; + int pid; + Rune r; + stop = ifs->val?ifs->val->word:""; if(pipe(pfd)<0){ Xerror("can't make pipe"); return; @@ -116,30 +110,31 @@ Xbackq(void) addwaitpid(pid); close(pfd[PWR]); f = openfd(pfd[PRD]); - s = wd = ewd = 0; + s = wd; v = 0; while((c = rchr(f))!=EOF){ - if(s==ewd){ - l = s-wd; - wd = erealloc(wd, l+Stralloc); - ewd = wd+l+Stralloc-1; - s = wd+l; - } - if(strchr(stop, c)){ - if(s!=wd){ - *s='\0'; - v = newword(wd, v); - s = wd; + if(s != ewd) { + *s++ = c; + for(q=stop; *q; q+=n) { + n = chartorune(&r, q); + if(s-wd >= n && memcmp(s-n, q, n) == 0) { + s -= n; + goto stop; + } } + continue; + } + stop: + if(s != wd) { + *s = '\0'; + v = newword(wd, v); } - else *s++=c; + s = wd; } if(s!=wd){ *s='\0'; v = newword(wd, v); } - if(wd) - efree(wd); closeio(f); Waitfor(pid, 0); /* v points to reversed arglist -- reverse it onto argv */ @@ -149,7 +144,7 @@ Xbackq(void) runq->argv->words = v; v = nextv; } - runq->pc = runq->code[runq->pc].i; + p->pc = p->code[p->pc].i; return; } } @@ -161,18 +156,33 @@ Xpipefd(void) int pc = p->pc, pid; char name[40]; int pfd[2]; - int sidefd, mainfd; - if(pipe(pfd)<0){ - Xerror("can't get pipe"); - return; + struct { int sidefd, mainfd; } fd[2], *r, *w; + + r = &fd[0]; + w = &fd[1]; + switch(p->code[pc].i){ + case READ: + w = nil; + break; + case WRITE: + r = nil; } - if(p->code[pc].i==READ){ - sidefd = pfd[PWR]; - mainfd = pfd[PRD]; + + if(r){ + if(pipe(pfd)<0){ + Xerror("can't get pipe"); + return; + } + r->sidefd = pfd[PWR]; + r->mainfd = pfd[PRD]; } - else{ - sidefd = pfd[PRD]; - mainfd = pfd[PWR]; + if(w){ + if(pipe(pfd)<0){ + Xerror("can't get pipe"); + return; + } + w->sidefd = pfd[PRD]; + w->mainfd = pfd[PWR]; } switch(pid = fork()){ case -1: @@ -181,17 +191,32 @@ Xpipefd(void) case 0: clearwaitpids(); start(p->code, pc+2, runq->local); - close(mainfd); - pushredir(ROPEN, sidefd, p->code[pc].i==READ?1:0); + if(r){ + close(r->mainfd); + pushredir(ROPEN, r->sidefd, 1); + } + if(w){ + close(w->mainfd); + pushredir(ROPEN, w->sidefd, 0); + } runq->ret = 0; break; default: addwaitpid(pid); - close(sidefd); - pushredir(ROPEN, mainfd, mainfd); /* isn't this a noop? */ - strcpy(name, Fdprefix); - inttoascii(name+strlen(name), mainfd); - pushword(name); + if(w){ + close(w->sidefd); + pushredir(ROPEN, w->mainfd, w->mainfd); /* so that Xpopredir can close it later */ + strcpy(name, Fdprefix); + inttoascii(name+strlen(name), w->mainfd); + pushword(name); + } + if(r){ + close(r->sidefd); + pushredir(ROPEN, r->mainfd, r->mainfd); + strcpy(name, Fdprefix); + inttoascii(name+strlen(name), r->mainfd); + pushword(name); + } p->pc = p->code[pc+1].i; break; }