20060303a

1 files changed, 205 insertions, 0 deletions

diff --git a/emu/Hp/cmd.c b/emu/Hp/cmd.c
new file mode 100644
index 00000000..97e303ac
--- /dev/null
+++ b/emu/Hp/cmd.c
@@ -0,0 +1,205 @@
+#include	<sys/types.h>
+#include	<signal.h>
+#include 	<pwd.h>
+#include	<sys/resource.h>
+#include	<sys/wait.h>
+#include	<fcntl.h>
+
+#include	"dat.h"
+#include	"fns.h"
+#include	"error.h"
+
+enum
+{
+	Debug = 0
+};
+
+/*
+ * os-specific devcmd support.
+ * this version should be reasonably portable across Unix systems.
+ */
+typedef struct Targ Targ;
+struct Targ
+{
+	int	fd[2];	/* fd[0] is standard input, fd[1] is standard output */
+	char**	args;
+	char*	dir;
+	int	pid;
+	int	wfd;	/* child writes errors that occur after the fork or on exec */
+	int	uid;
+	int	gid;
+};
+
+extern int gidnobody;
+extern int uidnobody;
+
+static int
+childproc(Targ *t)
+{
+	int i, nfd;
+
+	if(Debug)
+		print("devcmd: '%s'", t->args[0]);
+
+	nfd = getdtablesize();
+	for(i = 0; i < nfd; i++)
+		if(i != t->fd[0] && i != t->fd[1] && i != t->wfd)
+			close(i);
+
+	dup2(t->fd[0], 0);
+	dup2(t->fd[1], 1);
+	dup2(t->fd[1], 2);
+	close(t->fd[0]);
+	close(t->fd[1]);
+
+	if(t->gid != -1){
+		if(setgid(t->gid) < 0 && getegid() == 0){
+			fprint(t->wfd, "can't set gid %d: %s", t->gid, strerror(errno));
+			_exit(1);
+		}
+	}
+
+	if(t->uid != -1){
+		if(setuid(t->uid) < 0 && geteuid() == 0){
+			fprint(t->wfd, "can't set uid %d: %s", t->uid, strerror(errno));
+			_exit(1);
+		}
+	}
+
+	if(t->dir != nil && chdir(t->dir) < 0){
+		fprint(t->wfd, "can't chdir to %s: %s", t->dir, strerror(errno));
+		_exit(1);
+	}
+
+	signal(SIGPIPE, SIG_DFL);
+
+	execvp(t->args[0], t->args);
+	if(Debug)
+		print("execvp: %s\n",strerror(errno));
+	fprint(t->wfd, "exec failed: %s", strerror(errno));
+
+	_exit(1);
+}
+
+void*
+oscmd(char **args, int nice, char *dir, int *rfd, int *sfd)
+{
+	Dir *d;
+	Targ *t;
+	int r, fd0[2], fd1[2], wfd[2], n, pid;
+
+	t = mallocz(sizeof(*t), 1);
+	if(t == nil)
+		return nil;
+
+	fd0[0] = fd0[1] = -1;
+	fd1[0] = fd1[1] = -1;
+	wfd[0] = wfd[1] = -1;
+	if(pipe(fd0) < 0 || pipe(fd1) < 0 || pipe(wfd) < 0)
+		goto Error;
+	if(fcntl(wfd[1], F_SETFD, FD_CLOEXEC) < 0)	/* close on exec to give end of file on success */
+		goto Error;
+
+	t->fd[0] = fd0[0];
+	t->fd[1] = fd1[1];
+	t->wfd = wfd[1];
+	t->args = args;
+	t->dir = dir;
+	t->gid = up->env->gid;
+	if(t->gid == -1)
+		t->gid = gidnobody;
+	t->uid = up->env->uid;
+	if(t->uid == -1)
+		t->uid = uidnobody;
+
+	signal(SIGCHLD, SIG_DFL);
+	switch(pid = fork()) {
+	case -1:
+		goto Error;
+	case 0:
+		setpgrp();
+		if(nice)
+			oslopri();
+		childproc(t);
+		_exit(1);
+	default:
+		t->pid = pid;
+		if(Debug)
+			print("cmd pid %d\n", t->pid);
+		break;
+	}
+
+	close(fd0[0]);
+	close(fd1[1]);
+	close(wfd[1]);
+
+	n = read(wfd[0], up->genbuf, sizeof(up->genbuf)-1);
+	close(wfd[0]);
+	if(n > 0){
+		close(fd0[1]);
+		close(fd1[0]);
+		free(t);
+		up->genbuf[n] = 0;
+		if(Debug)
+			print("oscmd: bad exec: %q\n", up->genbuf);
+		error(up->genbuf);
+		return nil;
+	}
+
+	*sfd = fd0[1];
+	*rfd = fd1[0];
+	return t;
+
+Error:
+	r = errno;
+	if(Debug)
+		print("oscmd: %q\n",strerror(r));
+	close(fd0[0]);
+	close(fd0[1]);
+	close(fd1[0]);
+	close(fd1[1]);
+	close(wfd[0]);
+	close(wfd[1]);
+	error(strerror(r));
+	return nil;
+}
+
+int
+oscmdkill(void *a)
+{
+	Targ *t = a;
+
+	if(Debug)
+		print("kill: %d\n", t->pid);
+	return kill(-t->pid, SIGTERM);
+}
+
+int
+oscmdwait(void *a, char *buf, int n)
+{
+	Targ *t = a;
+	int s;
+
+	if(waitpid(t->pid, &s, 0) == -1){
+		if(Debug)
+			print("wait error: %d [in %d] %q\n", t->pid, getpid(), strerror(errno));
+		return -1;
+	}
+	if(WIFEXITED(s)){
+		if(WEXITSTATUS(s) == 0)
+			return snprint(buf, n, "%d 0 0 0 ''", t->pid);
+		return snprint(buf, n, "%d 0 0 0 'exit: %d'", t->pid, WEXITSTATUS(s));
+	}
+	if(WIFSIGNALED(s)){
+		if(WTERMSIG(s) == SIGTERM || WTERMSIG(s) == SIGKILL)
+			return snprint(buf, n, "%d 0 0 0 killed", t->pid);
+		return snprint(buf, n, "%d 0 0 0 'signal: %d'", t->pid, WTERMSIG(s));
+	}
+	return snprint(buf, n, "%d 0 0 0 'odd status: 0x%x'", t->pid, s);
+}
+
+void
+oscmdfree(void *a)
+{
+	free(a);
+}