scc

commit 540b7b0aa13418274213617487ed4c7c4d5e64a3
parent bc8e04323b76bf135995d22ecacf9a3cf987901c
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Wed, 18 May 2022 18:38:54 +0200

libc/posix: Add system()

Diffstat:
M
src/libc/arch/posix/Makefile
 | 
1
+
A
src/libc/arch/posix/system.c
 | 
34
++++++++++++++++++++++++++++++++++
M
src/libc/objs/amd64-linux.mk
 | 
1
+
M
src/libc/objs/amd64-netbsd.mk
 | 
1
+
M
src/libc/objs/amd64-openbsd.mk
 | 
1
+

5 files changed, 38 insertions(+), 0 deletions(-)
diff --git a/src/libc/arch/posix/Makefile b/src/libc/arch/posix/Makefile
@@ -13,6 +13,7 @@ OBJS=\
 	getenv.$O\
 	raise.$O\
 	signal.$O\
+	system.$O\
 	time.$O\
 
 all: $(OBJS)
diff --git a/src/libc/arch/posix/system.c b/src/libc/arch/posix/system.c
@@ -0,0 +1,34 @@
+#include <sys.h>
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include "../../syscall.h"
+
+#define SHELL "/bin/sh"
+
+#undef system
+
+extern char **_environ;
+
+int
+system(const char *cmd)
+{
+	int st;
+	pid_t pid;
+
+	if (!cmd)
+		return _access(SHELL, X_OK);
+
+	switch ((pid = _fork())) {
+	case -1:
+		return -1;
+	case 0:
+		_execve(SHELL, (char*[]) {"sh", "-c", cmd, NULL}, _environ);
+		_exit(127);
+	default:
+		while (_waitpid(pid, &st, 0) < 0 && errno == EINTR)
+			;
+		return st;
+	}
+}
diff --git a/src/libc/objs/amd64-linux.mk b/src/libc/objs/amd64-linux.mk
@@ -44,5 +44,6 @@ OBJS =\
 	arch/posix/getenv.$O\
 	arch/posix/raise.$O\
 	arch/posix/signal.$O\
+	arch/posix/system.$O\
 	arch/posix/time.$O\
 	string/strlen.$O\
diff --git a/src/libc/objs/amd64-netbsd.mk b/src/libc/objs/amd64-netbsd.mk
@@ -37,5 +37,6 @@ OBJS =\
 	arch/posix/getenv.$O\
 	arch/posix/raise.$O\
 	arch/posix/signal.$O\
+	arch/posix/system.$O\
 	arch/posix/time.$O\
 	string/strlen.$O\
diff --git a/src/libc/objs/amd64-openbsd.mk b/src/libc/objs/amd64-openbsd.mk
@@ -36,5 +36,6 @@ OBJS =\
 	arch/posix/getenv.$O\
 	arch/posix/raise.$O\
 	arch/posix/signal.$O\
+	arch/posix/system.$O\
 	arch/posix/time.$O\
 	string/strlen.$O\