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#include "rc.h"
// -----------------------------------------------------------------------
// internal
static
char**
mkargv(Word *args)
{
char **argv=emalloc((count(args)+2)*sizeof(char *));
char **argp=argv+1; /* leave one at front for runcoms */
for(;args;args=args->link)
*argp++=args->str;
*argp=nil;
return argv;
}
static
Word*
envval(char *s)
{
Word *v;
char *t, c;
for(t=s; *t && *t!='\1'; t++)
;
c = *t;
*t = '\0';
v = makeword(s, (c=='\0') ? nil : envval(t+1));
*t=c;
return v;
}
// -----------------------------------------------------------------------
// exported
void
initenv(void)
{
extern char **environ;
char *s;
char **env;
for(env=environ; *env; env++) {
for(s=*env; *s && *s != '(' && *s != '='; s++)
;
switch(*s){
case '\0':
break;
case '(': /* ignore functions */
break;
case '=':
*s = '\0';
setvar(*env, envval(s+1));
*s = '=';
break;
}
}
}
void
execute(Word *cmd, Word *path)
{
int nc;
char **argv = mkargv(cmd);
char **env = mkenv();
char file[1024];
for(; path; path=path->link){
nc = strlen(path->str);
if(nc < arrlen(file)){
strcpy(file, path->str);
if(file[0]){
strcat(file, "/");
nc++;
}
if(nc+strlen(argv[1]) < arrlen(file)){
strcat(file, argv[1]);
execve(file, argv+1, env);
}else
fatal("command name too long");
}
}
print(shell.err, "could not execute command: %s\n", argv[1]);
efree(argv);
}
void
redirect(Redir *r)
{
if(r){
redirect(r->link);
switch(r->type){
case Ropen:
if(r->from != r->to){
dup2(r->from, r->to);
close(r->from);
}
break;
case Rdupfd:
dup2(r->from, r->to); // TODO: error checking
break;
case Rclose:
close(r->from);
break;
default:
fatal("unrecognized redirection type %d\n", r->type);
}
}
}
int
mapfd(int fd)
{
Redir *r;
for(r = runner->redir.end; r; r = r->link){
switch(r->type){
case Rclose:
if(r->from == fd)
fd = -1;
break;
case Rdupfd:
case Ropen:
if(r->to == fd)
fd = r->from;
break;
}
}
return fd;
}
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